[PATCH/RFC V2 00/16] UFS: Power managment support

[PATCH/RFC V2 00/16] UFS: Power managment support

[Dolev Raviv]

This patch seies introduces support for power managment in the driver as well as vendor specific initialization - registers, clocks, voltage regulators etc.

It includes also a rework for the init sequnce and other PM pre-requisit such as write protection support, handling well-known LUN, error handling (retries), bkops, START_STOP unit command, and ICC levels settings.

--
Changes from V1:
 - 6 new patches apended at the end
 - Allow overriding power configuration with controller support and
   preferences/capabilities <Dolev Raviv>
 - Allow overriding power choice with controller capabilities <Dolev Raviv>
 - Add support for clock gating and clock scaling <Sahitya Tummala>
 - Add capability to control the auto bkops during suspend <Subhash Jadavani>
 - Add misc changes for phy/unipro driver usage <Dolev Raviv>

Dolev Raviv (2):
  scsi: ufs: refactor configuring power mode
  scsi: ufs: definitions for phy interface

Sahitya Tummala (3):
  scsi: ufs: Add support for clock gating
  scsi: ufs: Add freq-table-hz property for UFS device
  scsi: ufs: Add support for clock scaling using devfreq framework

Subhash Jadavani (5):
  scsi: ufs: refactor query descriptor API support
  scsi: support well known logical units
  scsi: ufs: introduce well known logical unit in ufs
  scsi: ufs: add UFS power management support
  scsi: ufs: add capability to control the auto bkops during suspend

Sujit Reddy Thumma (5):
  scsi: ufs: Allow vendor specific initialization
  scsi: ufs: Add regulator enable support
  scsi: ufs: Add clock initialization support
  scsi: ufs: improve init sequence
  scsi: sd: Avoid sending medium write commands if device is write
    protected

Yaniv Gardi (1):
  scsi: ufs: Active Power Mode - configuring bActiveICCLevel

 .../devicetree/bindings/ufs/ufshcd-pltfrm.txt      |   37 +
 drivers/scsi/scsi_scan.c                           |   16 +
 drivers/scsi/scsi_sysfs.c                          |    7 +
 drivers/scsi/sd.c                                  |    6 +-
 drivers/scsi/ufs/Kconfig                           |    2 +
 drivers/scsi/ufs/ufs.h                             |  131 +-
 drivers/scsi/ufs/ufshcd-pci.c                      |   55 +-
 drivers/scsi/ufs/ufshcd-pltfrm.c                   |  282 ++-
 drivers/scsi/ufs/ufshcd.c                          | 2400 ++++++++++++++++++--
 drivers/scsi/ufs/ufshcd.h                          |  277 ++-
 drivers/scsi/ufs/ufshci.h                          |    9 +-
 drivers/scsi/ufs/unipro.h                          |   56 +
 include/scsi/scsi.h                                |    1 +
 include/scsi/scsi_host.h                           |    5 +
 14 files changed, 2959 insertions(+), 325 deletions(-)

-- 
1.8.5.2

[PATCH/RFC V2 01/16] scsi: ufs: Allow vendor specific initialization

[Dolev Raviv]

From: Sujit Reddy Thumma <sthumma@codeaurora.org>

Some vendor specific controller versions might need to configure
vendor specific - registers, clocks, voltage regulators etc. to
initialize the host controller UTP layer and Uni-Pro stack.
Provide some common initialization operations that can be used
to configure vendor specifics. The methods can be extended in
future, for example, for power mode transitions.

The operations are vendor/board specific and hence determined with
the help of compatible property in device tree.

Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>

diff --git a/drivers/scsi/ufs/ufshcd-pci.c b/drivers/scsi/ufs/ufshcd-pci.c
index c007a7a..11a3237 100644
--- a/drivers/scsi/ufs/ufshcd-pci.c
+++ b/drivers/scsi/ufs/ufshcd-pci.c
@@ -164,7 +164,13 @@ ufshcd_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 
 	mmio_base = pcim_iomap_table(pdev)[0];
 
-	err = ufshcd_init(&pdev->dev, &hba, mmio_base, pdev->irq);
+	err = ufshcd_alloc_host(&pdev->dev, &hba);
+	if (err) {
+		dev_err(&pdev->dev, "Allocation failed\n");
+		return err;
+	}
+
+	err = ufshcd_init(hba, mmio_base, pdev->irq);
 	if (err) {
 		dev_err(&pdev->dev, "Initialization failed\n");
 		return err;
diff --git a/drivers/scsi/ufs/ufshcd-pltfrm.c b/drivers/scsi/ufs/ufshcd-pltfrm.c
index 5e46232..d727b1a 100644
--- a/drivers/scsi/ufs/ufshcd-pltfrm.c
+++ b/drivers/scsi/ufs/ufshcd-pltfrm.c
@@ -35,9 +35,24 @@
 
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
+#include <linux/of.h>
 
 #include "ufshcd.h"
 
+static const struct of_device_id ufs_of_match[];
+static struct ufs_hba_variant_ops *get_variant_ops(struct device *dev)
+{
+	if (dev->of_node) {
+		const struct of_device_id *match;
+
+		match = of_match_node(ufs_of_match, dev->of_node);
+		if (match)
+			return (struct ufs_hba_variant_ops *)match->data;
+	}
+
+	return NULL;
+}
+
 #ifdef CONFIG_PM
 /**
  * ufshcd_pltfrm_suspend - suspend power management function
@@ -138,8 +153,8 @@ static int ufshcd_pltfrm_probe(struct platform_device *pdev)
 
 	mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	mmio_base = devm_ioremap_resource(dev, mem_res);
-	if (IS_ERR(mmio_base)) {
-		err = PTR_ERR(mmio_base);
+	if (IS_ERR(*(void **)&mmio_base)) {
+		err = PTR_ERR(*(void **)&mmio_base);
 		goto out;
 	}
 
@@ -150,10 +165,18 @@ static int ufshcd_pltfrm_probe(struct platform_device *pdev)
 		goto out;
 	}
 
+	err = ufshcd_alloc_host(dev, &hba);
+	if (err) {
+		dev_err(&pdev->dev, "Allocation failed\n");
+		goto out;
+	}
+
+	hba->vops = get_variant_ops(&pdev->dev);
+
 	pm_runtime_set_active(&pdev->dev);
 	pm_runtime_enable(&pdev->dev);
 
-	err = ufshcd_init(dev, &hba, mmio_base, irq);
+	err = ufshcd_init(hba, mmio_base, irq);
 	if (err) {
 		dev_err(dev, "Intialization failed\n");
 		goto out_disable_rpm;
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index ba27215..d0565b0 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -3,6 +3,7 @@
  *
  * This code is based on drivers/scsi/ufs/ufshcd.c
  * Copyright (C) 2011-2013 Samsung India Software Operations
+ * Copyright (c) 2013-2014, The Linux Foundation. All rights reserved.
  *
  * Authors:
  *	Santosh Yaraganavi <santosh.sy@samsung.com>
@@ -31,6 +32,9 @@
  * circumstances will the contributor of this Program be liable for
  * any damages of any kind arising from your use or distribution of
  * this program.
+ *
+ * The Linux Foundation chooses to take subject only to the GPLv2
+ * license terms, and distributes only under these terms.
  */
 
 #include <linux/async.h>
@@ -175,13 +179,14 @@ static inline u32 ufshcd_get_ufs_version(struct ufs_hba *hba)
 /**
  * ufshcd_is_device_present - Check if any device connected to
  *			      the host controller
- * @reg_hcs - host controller status register value
+ * @hba: pointer to adapter instance
  *
  * Returns 1 if device present, 0 if no device detected
  */
-static inline int ufshcd_is_device_present(u32 reg_hcs)
+static inline int ufshcd_is_device_present(struct ufs_hba *hba)
 {
-	return (DEVICE_PRESENT & reg_hcs) ? 1 : 0;
+	return (ufshcd_readl(hba, REG_CONTROLLER_STATUS) &
+						DEVICE_PRESENT) ? 1 : 0;
 }
 
 /**
@@ -1798,11 +1803,10 @@ out:
  * @hba: per adapter instance
  *
  * To bring UFS host controller to operational state,
- * 1. Check if device is present
- * 2. Enable required interrupts
- * 3. Configure interrupt aggregation
- * 4. Program UTRL and UTMRL base addres
- * 5. Configure run-stop-registers
+ * 1. Enable required interrupts
+ * 2. Configure interrupt aggregation
+ * 3. Program UTRL and UTMRL base addres
+ * 4. Configure run-stop-registers
  *
  * Returns 0 on success, non-zero value on failure
  */
@@ -1811,14 +1815,6 @@ static int ufshcd_make_hba_operational(struct ufs_hba *hba)
 	int err = 0;
 	u32 reg;
 
-	/* check if device present */
-	reg = ufshcd_readl(hba, REG_CONTROLLER_STATUS);
-	if (!ufshcd_is_device_present(reg)) {
-		dev_err(hba->dev, "cc: Device not present\n");
-		err = -ENXIO;
-		goto out;
-	}
-
 	/* Enable required interrupts */
 	ufshcd_enable_intr(hba, UFSHCD_ENABLE_INTRS);
 
@@ -1839,6 +1835,7 @@ static int ufshcd_make_hba_operational(struct ufs_hba *hba)
 	 * UCRDY, UTMRLDY and UTRLRDY bits must be 1
 	 * DEI, HEI bits must be 0
 	 */
+	reg = ufshcd_readl(hba, REG_CONTROLLER_STATUS);
 	if (!(ufshcd_get_lists_status(reg))) {
 		ufshcd_enable_run_stop_reg(hba);
 	} else {
@@ -1885,6 +1882,9 @@ static int ufshcd_hba_enable(struct ufs_hba *hba)
 		msleep(5);
 	}
 
+	if (hba->vops && hba->vops->hce_enable_notify)
+		hba->vops->hce_enable_notify(hba, PRE_CHANGE);
+
 	/* start controller initialization sequence */
 	ufshcd_hba_start(hba);
 
@@ -1912,6 +1912,10 @@ static int ufshcd_hba_enable(struct ufs_hba *hba)
 		}
 		msleep(5);
 	}
+
+	if (hba->vops && hba->vops->hce_enable_notify)
+		hba->vops->hce_enable_notify(hba, POST_CHANGE);
+
 	return 0;
 }
 
@@ -1928,12 +1932,28 @@ static int ufshcd_link_startup(struct ufs_hba *hba)
 	/* enable UIC related interrupts */
 	ufshcd_enable_intr(hba, UIC_COMMAND_COMPL);
 
+	if (hba->vops && hba->vops->link_startup_notify)
+		hba->vops->link_startup_notify(hba, PRE_CHANGE);
+
 	ret = ufshcd_dme_link_startup(hba);
 	if (ret)
 		goto out;
 
-	ret = ufshcd_make_hba_operational(hba);
+	/* check if device is detected by inter-connect layer */
+	if (!ufshcd_is_device_present(hba)) {
+		dev_err(hba->dev, "%s: Device not present\n", __func__);
+		ret = -ENXIO;
+		goto out;
+	}
+
+	/* Include any host controller configuration via UIC commands */
+	if (hba->vops && hba->vops->link_startup_notify) {
+		ret = hba->vops->link_startup_notify(hba, POST_CHANGE);
+		if (ret)
+			goto out;
+	}
 
+	ret = ufshcd_make_hba_operational(hba);
 out:
 	if (ret)
 		dev_err(hba->dev, "link startup failed %d\n", ret);
@@ -3173,6 +3193,61 @@ static struct scsi_host_template ufshcd_driver_template = {
 	.can_queue		= UFSHCD_CAN_QUEUE,
 };
 
+static int ufshcd_variant_hba_init(struct ufs_hba *hba)
+{
+	int err = 0;
+
+	if (!hba->vops)
+		goto out;
+
+	if (hba->vops->init) {
+		err = hba->vops->init(hba);
+		if (err)
+			goto out;
+	}
+
+	if (hba->vops->setup_clocks) {
+		err = hba->vops->setup_clocks(hba, true);
+		if (err)
+			goto out_exit;
+	}
+
+	if (hba->vops->setup_regulators) {
+		err = hba->vops->setup_regulators(hba, true);
+		if (err)
+			goto out_clks;
+	}
+
+	goto out;
+
+out_clks:
+	if (hba->vops->setup_clocks)
+		hba->vops->setup_clocks(hba, false);
+out_exit:
+	if (hba->vops->exit)
+		hba->vops->exit(hba);
+out:
+	if (err)
+		dev_err(hba->dev, "%s: variant %s init failed err %d\n",
+			__func__, hba->vops ? hba->vops->name : "", err);
+	return err;
+}
+
+static void ufshcd_variant_hba_exit(struct ufs_hba *hba)
+{
+	if (!hba->vops)
+		return;
+
+	if (hba->vops->setup_clocks)
+		hba->vops->setup_clocks(hba, false);
+
+	if (hba->vops->setup_regulators)
+		hba->vops->setup_regulators(hba, false);
+
+	if (hba->vops->exit)
+		hba->vops->exit(hba);
+}
+
 /**
  * ufshcd_suspend - suspend power management function
  * @hba: per adapter instance
@@ -3257,6 +3332,8 @@ void ufshcd_remove(struct ufs_hba *hba)
 	ufshcd_hba_stop(hba);
 
 	scsi_host_put(hba->host);
+
+	ufshcd_variant_hba_exit(hba);
 }
 EXPORT_SYMBOL_GPL(ufshcd_remove);
 
@@ -3277,19 +3354,16 @@ static int ufshcd_set_dma_mask(struct ufs_hba *hba)
 }
 
 /**
- * ufshcd_init - Driver initialization routine
+ * ufshcd_alloc_host - allocate Host Bus Adapter (HBA)
  * @dev: pointer to device handle
  * @hba_handle: driver private handle
- * @mmio_base: base register address
- * @irq: Interrupt line of device
  * Returns 0 on success, non-zero value on failure
  */
-int ufshcd_init(struct device *dev, struct ufs_hba **hba_handle,
-		 void __iomem *mmio_base, unsigned int irq)
+int ufshcd_alloc_host(struct device *dev, struct ufs_hba **hba_handle)
 {
 	struct Scsi_Host *host;
 	struct ufs_hba *hba;
-	int err;
+	int err = 0;
 
 	if (!dev) {
 		dev_err(dev,
@@ -3298,13 +3372,6 @@ int ufshcd_init(struct device *dev, struct ufs_hba **hba_handle,
 		goto out_error;
 	}
 
-	if (!mmio_base) {
-		dev_err(dev,
-		"Invalid memory reference for mmio_base is NULL\n");
-		err = -ENODEV;
-		goto out_error;
-	}
-
 	host = scsi_host_alloc(&ufshcd_driver_template,
 				sizeof(struct ufs_hba));
 	if (!host) {
@@ -3315,9 +3382,40 @@ int ufshcd_init(struct device *dev, struct ufs_hba **hba_handle,
 	hba = shost_priv(host);
 	hba->host = host;
 	hba->dev = dev;
+	*hba_handle = hba;
+
+out_error:
+	return err;
+}
+EXPORT_SYMBOL(ufshcd_alloc_host);
+
+/**
+ * ufshcd_init - Driver initialization routine
+ * @hba: per-adapter instance
+ * @mmio_base: base register address
+ * @irq: Interrupt line of device
+ * Returns 0 on success, non-zero value on failure
+ */
+int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq)
+{
+	int err;
+	struct Scsi_Host *host = hba->host;
+	struct device *dev = hba->dev;
+
+	if (!mmio_base) {
+		dev_err(hba->dev,
+		"Invalid memory reference for mmio_base is NULL\n");
+		err = -ENODEV;
+		goto out_error;
+	}
+
 	hba->mmio_base = mmio_base;
 	hba->irq = irq;
 
+	err = ufshcd_variant_hba_init(hba);
+	if (err)
+		goto out_error;
+
 	/* Read capabilities registers */
 	ufshcd_hba_capabilities(hba);
 
@@ -3395,8 +3493,6 @@ int ufshcd_init(struct device *dev, struct ufs_hba **hba_handle,
 		goto out_remove_scsi_host;
 	}
 
-	*hba_handle = hba;
-
 	/* Hold auto suspend until async scan completes */
 	pm_runtime_get_sync(dev);
 
@@ -3408,6 +3504,7 @@ out_remove_scsi_host:
 	scsi_remove_host(hba->host);
 out_disable:
 	scsi_host_put(host);
+	ufshcd_variant_hba_exit(hba);
 out_error:
 	return err;
 }
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index acf318e..8c6bec0 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -68,6 +68,8 @@
 #define UFSHCD "ufshcd"
 #define UFSHCD_DRIVER_VERSION "0.2"
 
+struct ufs_hba;
+
 enum dev_cmd_type {
 	DEV_CMD_TYPE_NOP		= 0x0,
 	DEV_CMD_TYPE_QUERY		= 0x1,
@@ -152,6 +154,30 @@ struct ufs_dev_cmd {
 	struct ufs_query query;
 };
 
+#define PRE_CHANGE      0
+#define POST_CHANGE     1
+/**
+ * struct ufs_hba_variant_ops - variant specific callbacks
+ * @name: variant name
+ * @init: called when the driver is initialized
+ * @exit: called to cleanup everything done in init
+ * @setup_clocks: called before touching any of the controller registers
+ * @setup_regulators: called before accessing the host controller
+ * @hce_enable_notify: called before and after HCE enable bit is set to allow
+ *                     variant specific Uni-Pro initialization.
+ * @link_startup_notify: called before and after Link startup is carried out
+ *                       to allow variant specific Uni-Pro initialization.
+ */
+struct ufs_hba_variant_ops {
+	const char *name;
+	int	(*init)(struct ufs_hba *);
+	void    (*exit)(struct ufs_hba *);
+	int     (*setup_clocks)(struct ufs_hba *, bool);
+	int     (*setup_regulators)(struct ufs_hba *, bool);
+	int     (*hce_enable_notify)(struct ufs_hba *, bool);
+	int     (*link_startup_notify)(struct ufs_hba *, bool);
+};
+
 /**
  * struct ufs_hba - per adapter private structure
  * @mmio_base: UFSHCI base register address
@@ -171,6 +197,8 @@ struct ufs_dev_cmd {
  * @nutrs: Transfer Request Queue depth supported by controller
  * @nutmrs: Task Management Queue depth supported by controller
  * @ufs_version: UFS Version to which controller complies
+ * @vops: pointer to variant specific operations
+ * @priv: pointer to variant specific private data
  * @irq: Irq number of the controller
  * @active_uic_cmd: handle of active UIC command
  * @uic_cmd_mutex: mutex for uic command
@@ -218,6 +246,8 @@ struct ufs_hba {
 	int nutrs;
 	int nutmrs;
 	u32 ufs_version;
+	struct ufs_hba_variant_ops *vops;
+	void *priv;
 	unsigned int irq;
 
 	struct uic_command *active_uic_cmd;
@@ -256,8 +286,8 @@ struct ufs_hba {
 #define ufshcd_readl(hba, reg)	\
 	readl((hba)->mmio_base + (reg))
 
-int ufshcd_init(struct device *, struct ufs_hba ** , void __iomem * ,
-			unsigned int);
+int ufshcd_alloc_host(struct device *, struct ufs_hba **);
+int ufshcd_init(struct ufs_hba * , void __iomem * , unsigned int);
 void ufshcd_remove(struct ufs_hba *);
 
 /**
-- 
1.8.5.2
-- 
QUALCOMM ISRAEL, on behalf of Qualcomm Innovation Center, Inc. is a member
of Code Aurora Forum, hosted by The Linux Foundation

[PATCH/RFC V2 02/16] scsi: ufs: Add regulator enable support

[Dolev Raviv]

From: Sujit Reddy Thumma <sthumma@codeaurora.org>

UFS devices are powered by at most three external power supplies -
- VCC - The flash memory core power supply, 2.7V to 3.6V or 1.70V to 1.95V
- VCCQ - The controller and I/O power supply, 1.1V to 1.3V
- VCCQ2 - Secondary controller and/or I/O power supply, 1.65V to 1.95V

For some devices VCCQ or VCCQ2 are optional as they can be
generated using internal LDO inside the UFS device.

Add DT bindings for voltage regulators that can be controlled
from host driver.

Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>

diff --git a/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt b/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt
index 20468b2..65e3117 100644
--- a/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt
+++ b/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt
@@ -8,9 +8,33 @@ Required properties:
 - interrupts        : <interrupt mapping for UFS host controller IRQ>
 - reg               : <registers mapping>
 
+Optional properties:
+- vcc-supply            : phandle to VCC supply regulator node
+- vccq-supply           : phandle to VCCQ supply regulator node
+- vccq2-supply          : phandle to VCCQ2 supply regulator node
+- vcc-supply-1p8        : For embedded UFS devices, valid VCC range is 1.7-1.95V
+                          or 2.7-3.6V. This boolean property when set, specifies
+			  to use low voltage range of 1.7-1.95V. Note for external
+			  UFS cards this property is invalid and valid VCC range is
+			  always 2.7-3.6V.
+- vcc-max-microamp      : specifies max. load that can be drawn from vcc supply
+- vccq-max-microamp     : specifies max. load that can be drawn from vccq supply
+- vccq2-max-microamp    : specifies max. load that can be drawn from vccq2 supply
+
+Note: If above properties are not defined it can be assumed that the supply
+regulators are always on.
+
 Example:
 	ufshc@0xfc598000 {
 		compatible = "jedec,ufs-1.1";
 		reg = <0xfc598000 0x800>;
 		interrupts = <0 28 0>;
+
+		vcc-supply = <&xxx_reg1>;
+		vcc-supply-1p8;
+		vccq-supply = <&xxx_reg2>;
+		vccq2-supply = <&xxx_reg3>;
+		vcc-max-microamp = 500000;
+		vccq-max-microamp = 200000;
+		vccq2-max-microamp = 200000;
 	};
diff --git a/drivers/scsi/ufs/ufs.h b/drivers/scsi/ufs/ufs.h
index fafcf5e..729ce7d 100644
--- a/drivers/scsi/ufs/ufs.h
+++ b/drivers/scsi/ufs/ufs.h
@@ -362,4 +362,29 @@ struct ufs_query_res {
 	struct utp_upiu_query upiu_res;
 };
 
+#define UFS_VREG_VCC_MIN_UV	   2700000 /* uV */
+#define UFS_VREG_VCC_MAX_UV	   3600000 /* uV */
+#define UFS_VREG_VCC_1P8_MIN_UV    1700000 /* uV */
+#define UFS_VREG_VCC_1P8_MAX_UV    1950000 /* uV */
+#define UFS_VREG_VCCQ_MIN_UV	   1100000 /* uV */
+#define UFS_VREG_VCCQ_MAX_UV	   1300000 /* uV */
+#define UFS_VREG_VCCQ2_MIN_UV	   1650000 /* uV */
+#define UFS_VREG_VCCQ2_MAX_UV	   1950000 /* uV */
+
+struct ufs_vreg {
+	struct regulator *reg;
+	const char *name;
+	bool enabled;
+	int min_uV;
+	int max_uV;
+	int min_uA;
+	int max_uA;
+};
+
+struct ufs_vreg_info {
+	struct ufs_vreg *vcc;
+	struct ufs_vreg *vccq;
+	struct ufs_vreg *vccq2;
+};
+
 #endif /* End of Header */
diff --git a/drivers/scsi/ufs/ufshcd-pltfrm.c b/drivers/scsi/ufs/ufshcd-pltfrm.c
index d727b1a..51e47c4 100644
--- a/drivers/scsi/ufs/ufshcd-pltfrm.c
+++ b/drivers/scsi/ufs/ufshcd-pltfrm.c
@@ -53,6 +53,99 @@ static struct ufs_hba_variant_ops *get_variant_ops(struct device *dev)
 	return NULL;
 }
 
+#define MAX_PROP_SIZE 32
+static int ufshcd_populate_vreg(struct device *dev, const char *name,
+		struct ufs_vreg **out_vreg)
+{
+	int ret = 0;
+	char prop_name[MAX_PROP_SIZE];
+	struct ufs_vreg *vreg = NULL;
+	struct device_node *np = dev->of_node;
+
+	if (!np) {
+		dev_err(dev, "%s: non DT initialization\n", __func__);
+		goto out;
+	}
+
+	snprintf(prop_name, MAX_PROP_SIZE, "%s-supply", name);
+	if (!of_parse_phandle(np, prop_name, 0)) {
+		dev_info(dev, "%s: Unable to find %s regulator, assuming enabled\n",
+				__func__, prop_name);
+		goto out;
+	}
+
+	vreg = devm_kzalloc(dev, sizeof(*vreg), GFP_KERNEL);
+	if (!vreg) {
+		dev_err(dev, "No memory for %s regulator\n", name);
+		goto out;
+	}
+
+	vreg->name = kstrdup(name, GFP_KERNEL);
+
+	snprintf(prop_name, MAX_PROP_SIZE, "%s-max-microamp", name);
+	ret = of_property_read_u32(np, prop_name, &vreg->max_uA);
+	if (ret) {
+		dev_err(dev, "%s: unable to find %s err %d\n",
+				__func__, prop_name, ret);
+		goto out_free;
+	}
+
+	vreg->min_uA = 0;
+	if (!strcmp(name, "vcc")) {
+		if (of_property_read_bool(np, "vcc-supply-1p8")) {
+			vreg->min_uV = UFS_VREG_VCC_1P8_MIN_UV;
+			vreg->max_uV = UFS_VREG_VCC_1P8_MAX_UV;
+		} else {
+			vreg->min_uV = UFS_VREG_VCC_MIN_UV;
+			vreg->max_uV = UFS_VREG_VCC_MAX_UV;
+		}
+	} else if (!strcmp(name, "vccq")) {
+		vreg->min_uV = UFS_VREG_VCCQ_MIN_UV;
+		vreg->max_uV = UFS_VREG_VCCQ_MAX_UV;
+	} else if (!strcmp(name, "vccq2")) {
+		vreg->min_uV = UFS_VREG_VCCQ2_MIN_UV;
+		vreg->max_uV = UFS_VREG_VCCQ2_MAX_UV;
+	}
+
+	goto out;
+
+out_free:
+	devm_kfree(dev, vreg);
+	vreg = NULL;
+out:
+	if (!ret)
+		*out_vreg = vreg;
+	return ret;
+}
+
+/**
+ * ufshcd_parse_regulator_info - get regulator info from device tree
+ * @hba: per adapter instance
+ *
+ * Get regulator info from device tree for vcc, vccq, vccq2 power supplies.
+ * If any of the supplies are not defined it is assumed that they are always-on
+ * and hence return zero. If the property is defined but parsing is failed
+ * then return corresponding error.
+ */
+static int ufshcd_parse_regulator_info(struct ufs_hba *hba)
+{
+	int err;
+	struct device *dev = hba->dev;
+	struct ufs_vreg_info *info = &hba->vreg_info;
+
+	err = ufshcd_populate_vreg(dev, "vcc", &info->vcc);
+	if (err)
+		goto out;
+
+	err = ufshcd_populate_vreg(dev, "vccq", &info->vccq);
+	if (err)
+		goto out;
+
+	err = ufshcd_populate_vreg(dev, "vccq2", &info->vccq2);
+out:
+	return err;
+}
+
 #ifdef CONFIG_PM
 /**
  * ufshcd_pltfrm_suspend - suspend power management function
@@ -173,6 +266,13 @@ static int ufshcd_pltfrm_probe(struct platform_device *pdev)
 
 	hba->vops = get_variant_ops(&pdev->dev);
 
+	err = ufshcd_parse_regulator_info(hba);
+	if (err) {
+		dev_err(&pdev->dev, "%s: regulator init failed %d\n",
+				__func__, err);
+		goto out;
+	}
+
 	pm_runtime_set_active(&pdev->dev);
 	pm_runtime_enable(&pdev->dev);
 
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index d0565b0..ef8519e 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -68,6 +68,16 @@
 /* Interrupt aggregation default timeout, unit: 40us */
 #define INT_AGGR_DEF_TO	0x02
 
+#define ufshcd_toggle_vreg(_dev, _vreg, _on)				\
+	({                                                              \
+		int _ret;                                               \
+		if (_on)                                                \
+			_ret = ufshcd_enable_vreg(_dev, _vreg);         \
+		else                                                    \
+			_ret = ufshcd_disable_vreg(_dev, _vreg);        \
+		_ret;                                                   \
+	})
+
 enum {
 	UFSHCD_MAX_CHANNEL	= 0,
 	UFSHCD_MAX_ID		= 1,
@@ -3193,6 +3203,153 @@ static struct scsi_host_template ufshcd_driver_template = {
 	.can_queue		= UFSHCD_CAN_QUEUE,
 };
 
+static int ufshcd_config_vreg(struct device *dev,
+		struct ufs_vreg *vreg, bool on)
+{
+	int ret = 0;
+	struct regulator *reg = vreg->reg;
+	const char *name = vreg->name;
+	int min_uV, uA_load;
+
+	BUG_ON(!vreg);
+
+	if (regulator_count_voltages(reg) > 0) {
+		min_uV = on ? vreg->min_uV : 0;
+		ret = regulator_set_voltage(reg, min_uV, vreg->max_uV);
+		if (ret) {
+			dev_err(dev, "%s: %s set voltage failed, err=%d\n",
+					__func__, name, ret);
+			goto out;
+		}
+
+		uA_load = on ? vreg->max_uA : 0;
+		ret = regulator_set_optimum_mode(reg, uA_load);
+		if (ret >= 0) {
+			/*
+			 * regulator_set_optimum_mode() returns new regulator
+			 * mode upon success.
+			 */
+			ret = 0;
+		} else {
+			dev_err(dev, "%s: %s set optimum mode(uA_load=%d) failed, err=%d\n",
+					__func__, name, uA_load, ret);
+			goto out;
+		}
+	}
+out:
+	return ret;
+}
+
+static int ufshcd_enable_vreg(struct device *dev, struct ufs_vreg *vreg)
+{
+	int ret = 0;
+
+	if (!vreg || vreg->enabled)
+		goto out;
+
+	ret = ufshcd_config_vreg(dev, vreg, true);
+	if (!ret)
+		ret = regulator_enable(vreg->reg);
+
+	if (!ret)
+		vreg->enabled = true;
+	else
+		dev_err(dev, "%s: %s enable failed, err=%d\n",
+				__func__, vreg->name, ret);
+out:
+	return ret;
+}
+
+static int ufshcd_disable_vreg(struct device *dev, struct ufs_vreg *vreg)
+{
+	int ret = 0;
+
+	if (!vreg || !vreg->enabled)
+		goto out;
+
+	ret = regulator_disable(vreg->reg);
+
+	if (!ret) {
+		/* ignore errors on applying disable config */
+		ufshcd_config_vreg(dev, vreg, false);
+		vreg->enabled = false;
+	} else {
+		dev_err(dev, "%s: %s disable failed, err=%d\n",
+				__func__, vreg->name, ret);
+	}
+out:
+	return ret;
+}
+
+static int ufshcd_setup_vreg(struct ufs_hba *hba, bool on)
+{
+	int ret = 0;
+	struct device *dev = hba->dev;
+	struct ufs_vreg_info *info = &hba->vreg_info;
+
+	if (!info)
+		goto out;
+
+	ret = ufshcd_toggle_vreg(dev, info->vcc, on);
+	if (ret)
+		goto out;
+
+	ret = ufshcd_toggle_vreg(dev, info->vccq, on);
+	if (ret)
+		goto out;
+
+	ret = ufshcd_toggle_vreg(dev, info->vccq2, on);
+	if (ret)
+		goto out;
+
+out:
+	if (ret) {
+		ufshcd_toggle_vreg(dev, info->vccq2, false);
+		ufshcd_toggle_vreg(dev, info->vccq, false);
+		ufshcd_toggle_vreg(dev, info->vcc, false);
+	}
+	return ret;
+}
+
+static int ufshcd_get_vreg(struct device *dev, struct ufs_vreg *vreg)
+{
+	int ret = 0;
+
+	if (!vreg)
+		goto out;
+
+	vreg->reg = devm_regulator_get(dev, vreg->name);
+	if (IS_ERR(vreg->reg)) {
+		ret = PTR_ERR(vreg->reg);
+		dev_err(dev, "%s: %s get failed, err=%d\n",
+				__func__, vreg->name, ret);
+	}
+out:
+	return ret;
+}
+
+static int ufshcd_init_vreg(struct ufs_hba *hba)
+{
+	int ret = 0;
+	struct device *dev = hba->dev;
+	struct ufs_vreg_info *info = &hba->vreg_info;
+
+	if (!info)
+		goto out;
+
+	ret = ufshcd_get_vreg(dev, info->vcc);
+	if (ret)
+		goto out;
+
+	ret = ufshcd_get_vreg(dev, info->vccq);
+	if (ret)
+		goto out;
+
+	ret = ufshcd_get_vreg(dev, info->vccq2);
+out:
+	return ret;
+}
+
 static int ufshcd_variant_hba_init(struct ufs_hba *hba)
 {
 	int err = 0;
@@ -3248,6 +3405,36 @@ static void ufshcd_variant_hba_exit(struct ufs_hba *hba)
 		hba->vops->exit(hba);
 }
 
+static int ufshcd_hba_init(struct ufs_hba *hba)
+{
+	int err;
+
+	err = ufshcd_init_vreg(hba);
+	if (err)
+		goto out;
+
+	err = ufshcd_setup_vreg(hba, true);
+	if (err)
+		goto out;
+
+	err = ufshcd_variant_hba_init(hba);
+	if (err)
+		goto out_disable_vreg;
+
+	goto out;
+
+out_disable_vreg:
+	ufshcd_setup_vreg(hba, false);
+out:
+	return err;
+}
+
+static void ufshcd_hba_exit(struct ufs_hba *hba)
+{
+	ufshcd_variant_hba_exit(hba);
+	ufshcd_setup_vreg(hba, false);
+}
+
 /**
  * ufshcd_suspend - suspend power management function
  * @hba: per adapter instance
@@ -3333,7 +3520,7 @@ void ufshcd_remove(struct ufs_hba *hba)
 
 	scsi_host_put(hba->host);
 
-	ufshcd_variant_hba_exit(hba);
+	ufshcd_hba_exit(hba);
 }
 EXPORT_SYMBOL_GPL(ufshcd_remove);
 
@@ -3412,7 +3599,7 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq)
 	hba->mmio_base = mmio_base;
 	hba->irq = irq;
 
-	err = ufshcd_variant_hba_init(hba);
+	err = ufshcd_hba_init(hba);
 	if (err)
 		goto out_error;
 
@@ -3504,7 +3691,7 @@ out_remove_scsi_host:
 	scsi_remove_host(hba->host);
 out_disable:
 	scsi_host_put(host);
-	ufshcd_variant_hba_exit(hba);
+	ufshcd_hba_exit(hba);
 out_error:
 	return err;
 }
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index 8c6bec0..c0232f9 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -52,6 +52,7 @@
 #include <linux/pm_runtime.h>
 #include <linux/clk.h>
 #include <linux/completion.h>
+#include <linux/regulator/consumer.h>
 
 #include <asm/irq.h>
 #include <asm/byteorder.h>
@@ -219,6 +220,7 @@ struct ufs_hba_variant_ops {
  * @saved_uic_err: sticky UIC error mask
  * @dev_cmd: ufs device management command information
  * @auto_bkops_enabled: to track whether bkops is enabled in device
+ * @vreg_info: UFS device voltage regulator information
  */
 struct ufs_hba {
 	void __iomem *mmio_base;
@@ -279,6 +281,7 @@ struct ufs_hba {
 	struct ufs_dev_cmd dev_cmd;
 
 	bool auto_bkops_enabled;
+	struct ufs_vreg_info vreg_info;
 };
 
 #define ufshcd_writel(hba, val, reg)	\
-- 
1.8.5.2
-- 
QUALCOMM ISRAEL, on behalf of Qualcomm Innovation Center, Inc. is a member
of Code Aurora Forum, hosted by The Linux Foundation

[PATCH/RFC V2 03/16] scsi: ufs: Add clock initialization support

[Dolev Raviv]

From: Sujit Reddy Thumma <sthumma@codeaurora.org>

Add generic clock initialization support for UFSHCD platform
driver. The clock info is read from device tree using standard
clock bindings. A generic max-clock-frequency-hz property is
defined to save information on maximum operating clock frequency
the h/w supports.

Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>

diff --git a/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt b/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt
index 65e3117..b0f791a 100644
--- a/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt
+++ b/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt
@@ -21,8 +21,17 @@ Optional properties:
 - vccq-max-microamp     : specifies max. load that can be drawn from vccq supply
 - vccq2-max-microamp    : specifies max. load that can be drawn from vccq2 supply
 
+- clocks                : List of phandle and clock specifier pairs
+- clock-names           : List of clock input name strings sorted in the same
+                          order as the clocks property.
+- max-clock-frequency-hz : List of maximum operating frequency stored in the same
+                           order as the clocks property. If this property is not
+			   defined or a value in the array is "0" then it is assumed
+			   that the frequency is set by the parent clock or a
+			   fixed rate clock source.
+
 Note: If above properties are not defined it can be assumed that the supply
-regulators are always on.
+regulators or clocks are always on.
 
 Example:
 	ufshc@0xfc598000 {
@@ -37,4 +46,8 @@ Example:
 		vcc-max-microamp = 500000;
 		vccq-max-microamp = 200000;
 		vccq2-max-microamp = 200000;
+
+		clocks = <&core 0>, <&ref 0>, <&iface 0>;
+		clock-names = "core_clk", "ref_clk", "iface_clk";
+		max-clock-frequency-hz = <100000000 19200000 0>;
 	};
diff --git a/drivers/scsi/ufs/ufshcd-pci.c b/drivers/scsi/ufs/ufshcd-pci.c
index 11a3237..1aac2ef 100644
--- a/drivers/scsi/ufs/ufshcd-pci.c
+++ b/drivers/scsi/ufs/ufshcd-pci.c
@@ -170,6 +170,8 @@ ufshcd_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 		return err;
 	}
 
+	INIT_LIST_HEAD(&hba->clk_list_head);
+
 	err = ufshcd_init(hba, mmio_base, pdev->irq);
 	if (err) {
 		dev_err(&pdev->dev, "Initialization failed\n");
diff --git a/drivers/scsi/ufs/ufshcd-pltfrm.c b/drivers/scsi/ufs/ufshcd-pltfrm.c
index 51e47c4..642d80f 100644
--- a/drivers/scsi/ufs/ufshcd-pltfrm.c
+++ b/drivers/scsi/ufs/ufshcd-pltfrm.c
@@ -53,6 +53,71 @@ static struct ufs_hba_variant_ops *get_variant_ops(struct device *dev)
 	return NULL;
 }
 
+static int ufshcd_parse_clock_info(struct ufs_hba *hba)
+{
+	int ret = 0;
+	int cnt;
+	int i;
+	struct device *dev = hba->dev;
+	struct device_node *np = dev->of_node;
+	char *name;
+	u32 *clkfreq = NULL;
+	struct ufs_clk_info *clki;
+
+	if (!np)
+		goto out;
+
+	INIT_LIST_HEAD(&hba->clk_list_head);
+
+	cnt = of_property_count_strings(np, "clock-names");
+	if (!cnt || (cnt == -EINVAL)) {
+		dev_info(dev, "%s: Unable to find clocks, assuming enabled\n",
+				__func__);
+	} else if (cnt < 0) {
+		dev_err(dev, "%s: count clock strings failed, err %d\n",
+				__func__, cnt);
+		ret = cnt;
+	}
+
+	if (cnt <= 0)
+		goto out;
+
+	clkfreq = kzalloc(cnt * sizeof(*clkfreq), GFP_KERNEL);
+	if (!clkfreq) {
+		ret = -ENOMEM;
+		dev_err(dev, "%s: memory alloc failed\n", __func__);
+		goto out;
+	}
+
+	ret = of_property_read_u32_array(np,
+			"max-clock-frequency-hz", clkfreq, cnt);
+	if (ret && (ret != -EINVAL)) {
+		dev_err(dev, "%s: invalid max-clock-frequency-hz property, %d\n",
+				__func__, ret);
+		goto out;
+	}
+
+	for (i = 0; i < cnt; i++) {
+		ret = of_property_read_string_index(np,
+				"clock-names", i, (const char **)&name);
+		if (ret)
+			goto out;
+
+		clki = devm_kzalloc(dev, sizeof(*clki), GFP_KERNEL);
+		if (!clki) {
+			ret = -ENOMEM;
+			goto out;
+		}
+
+		clki->max_freq = clkfreq[i];
+		clki->name = kstrdup(name, GFP_KERNEL);
+		list_add_tail(&clki->list, &hba->clk_list_head);
+	}
+out:
+	kfree(clkfreq);
+	return ret;
+}
+
 #define MAX_PROP_SIZE 32
 static int ufshcd_populate_vreg(struct device *dev, const char *name,
 		struct ufs_vreg **out_vreg)
@@ -266,6 +331,12 @@ static int ufshcd_pltfrm_probe(struct platform_device *pdev)
 
 	hba->vops = get_variant_ops(&pdev->dev);
 
+	err = ufshcd_parse_clock_info(hba);
+	if (err) {
+		dev_err(&pdev->dev, "%s: clock parse failed %d\n",
+				__func__, err);
+		goto out;
+	}
 	err = ufshcd_parse_regulator_info(hba);
 	if (err) {
 		dev_err(&pdev->dev, "%s: regulator init failed %d\n",
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index ef8519e..b033702 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -3350,6 +3350,80 @@ out:
 	return ret;
 }
 
+static int ufshcd_setup_clocks(struct ufs_hba *hba, bool on)
+{
+	int ret = 0;
+	struct ufs_clk_info *clki;
+	struct list_head *head = &hba->clk_list_head;
+
+	if (!head || list_empty(head))
+		goto out;
+
+	list_for_each_entry(clki, head, list) {
+		if (!IS_ERR_OR_NULL(clki->clk)) {
+			if (on && !clki->enabled) {
+				ret = clk_prepare_enable(clki->clk);
+				if (ret) {
+					dev_err(hba->dev, "%s: %s prepare enable failed, %d\n",
+						__func__, clki->name, ret);
+					goto out;
+				}
+			} else if (!on && clki->enabled) {
+				clk_disable_unprepare(clki->clk);
+			}
+			clki->enabled = on;
+			dev_dbg(hba->dev, "%s: clk: %s %sabled\n", __func__,
+					clki->name, on ? "en" : "dis");
+		}
+	}
+out:
+	if (ret) {
+		list_for_each_entry(clki, head, list) {
+			if (!IS_ERR_OR_NULL(clki->clk) && clki->enabled)
+				clk_disable_unprepare(clki->clk);
+		}
+	}
+	return ret;
+}
+
+static int ufshcd_init_clocks(struct ufs_hba *hba)
+{
+	int ret = 0;
+	struct ufs_clk_info *clki;
+	struct device *dev = hba->dev;
+	struct list_head *head = &hba->clk_list_head;
+
+	if (!head || list_empty(head))
+		goto out;
+
+	list_for_each_entry(clki, head, list) {
+		if (!clki->name)
+			continue;
+
+		clki->clk = devm_clk_get(dev, clki->name);
+		if (IS_ERR(clki->clk)) {
+			ret = PTR_ERR(clki->clk);
+			dev_err(dev, "%s: %s clk get failed, %d\n",
+					__func__, clki->name, ret);
+			goto out;
+		}
+
+		if (clki->max_freq) {
+			ret = clk_set_rate(clki->clk, clki->max_freq);
+			if (ret) {
+				dev_err(hba->dev, "%s: %s clk set rate(%dHz) failed, %d\n",
+					__func__, clki->name,
+					clki->max_freq, ret);
+				goto out;
+			}
+		}
+		dev_dbg(dev, "%s: clk: %s, rate: %lu\n", __func__,
+				clki->name, clk_get_rate(clki->clk));
+	}
+out:
+	return ret;
+}
+
 static int ufshcd_variant_hba_init(struct ufs_hba *hba)
 {
 	int err = 0;
@@ -3409,14 +3483,22 @@ static int ufshcd_hba_init(struct ufs_hba *hba)
 {
 	int err;
 
-	err = ufshcd_init_vreg(hba);
+	err = ufshcd_init_clocks(hba);
 	if (err)
 		goto out;
 
-	err = ufshcd_setup_vreg(hba, true);
+	err = ufshcd_setup_clocks(hba, true);
 	if (err)
 		goto out;
 
+	err = ufshcd_init_vreg(hba);
+	if (err)
+		goto out_disable_clks;
+
+	err = ufshcd_setup_vreg(hba, true);
+	if (err)
+		goto out_disable_clks;
+
 	err = ufshcd_variant_hba_init(hba);
 	if (err)
 		goto out_disable_vreg;
@@ -3425,6 +3507,8 @@ static int ufshcd_hba_init(struct ufs_hba *hba)
 
 out_disable_vreg:
 	ufshcd_setup_vreg(hba, false);
+out_disable_clks:
+	ufshcd_setup_clocks(hba, false);
 out:
 	return err;
 }
@@ -3433,6 +3517,7 @@ static void ufshcd_hba_exit(struct ufs_hba *hba)
 {
 	ufshcd_variant_hba_exit(hba);
 	ufshcd_setup_vreg(hba, false);
+	ufshcd_setup_clocks(hba, false);
 }
 
 /**
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index c0232f9..bc0f7ed 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -155,6 +155,22 @@ struct ufs_dev_cmd {
 	struct ufs_query query;
 };
 
+/**
+ * struct ufs_clk_info - UFS clock related info
+ * @list: list headed by hba->clk_list_head
+ * @clk: clock node
+ * @name: clock name
+ * @max_freq: maximum frequency supported by the clock
+ * @enabled: variable to check against multiple enable/disable
+ */
+struct ufs_clk_info {
+	struct list_head list;
+	struct clk *clk;
+	const char *name;
+	u32 max_freq;
+	bool enabled;
+};
+
 #define PRE_CHANGE      0
 #define POST_CHANGE     1
 /**
@@ -221,6 +237,7 @@ struct ufs_hba_variant_ops {
  * @dev_cmd: ufs device management command information
  * @auto_bkops_enabled: to track whether bkops is enabled in device
  * @vreg_info: UFS device voltage regulator information
+ * @clk_list_head: UFS host controller clocks list node head
  */
 struct ufs_hba {
 	void __iomem *mmio_base;
@@ -282,6 +299,7 @@ struct ufs_hba {
 
 	bool auto_bkops_enabled;
 	struct ufs_vreg_info vreg_info;
+	struct list_head clk_list_head;
 };
 
 #define ufshcd_writel(hba, val, reg)	\
-- 
1.8.5.2
-- 
QUALCOMM ISRAEL, on behalf of Qualcomm Innovation Center, Inc. is a member
of Code Aurora Forum, hosted by The Linux Foundation

[PATCH/RFC V2 04/16] scsi: ufs: refactor query descriptor API support

[Dolev Raviv]

From: Subhash Jadavani <subhashj@codeaurora.org>

Currently reading query descriptor is more tightened to each
descriptor type. This patch generalize the approach and allows
reading any parameter from any query descriptor.

Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>

diff --git a/drivers/scsi/ufs/ufs.h b/drivers/scsi/ufs/ufs.h
index 729ce7d..7ea8e71 100644
--- a/drivers/scsi/ufs/ufs.h
+++ b/drivers/scsi/ufs/ufs.h
@@ -50,6 +50,8 @@
 			cpu_to_be32((byte3 << 24) | (byte2 << 16) |\
 			 (byte1 << 8) | (byte0))
 
+#define UFS_UPIU_MAX_GENERAL_LUN	8
+
 /*
  * UFS Protocol Information Unit related definitions
  */
@@ -129,10 +131,29 @@ enum desc_idn {
 	QUERY_DESC_IDN_RFU_1		= 0x6,
 	QUERY_DESC_IDN_GEOMETRY		= 0x7,
 	QUERY_DESC_IDN_POWER		= 0x8,
-	QUERY_DESC_IDN_RFU_2		= 0x9,
+	QUERY_DESC_IDN_MAX,
+};
+
+enum desc_header_offset {
+	QUERY_DESC_LENGTH_OFFSET	= 0x00,
+	QUERY_DESC_DESC_TYPE_OFFSET	= 0x01,
+};
+
+enum ufs_desc_max_size {
+	QUERY_DESC_DEVICE_MAX_SIZE		= 0x1F,
+	QUERY_DESC_CONFIGURAION_MAX_SIZE	= 0x90,
+	QUERY_DESC_UNIT_MAX_SIZE		= 0x23,
+	QUERY_DESC_INTERCONNECT_MAX_SIZE	= 0x06,
+	/*
+	 * Max. 126 UNICODE characters (2 bytes per character) plus 2 bytes
+	 * of descriptor header.
+	 */
+	QUERY_DESC_STRING_MAX_SIZE		= 0xFE,
+	QUERY_DESC_GEOMETRY_MAZ_SIZE		= 0x44,
+	QUERY_DESC_POWER_MAX_SIZE		= 0x62,
+	QUERY_DESC_RFU_MAX_SIZE			= 0x00,
 };
 
-#define UNIT_DESC_MAX_SIZE       0x22
 /* Unit descriptor parameters offsets in bytes*/
 enum unit_desc_param {
 	UNIT_DESC_PARAM_LEN			= 0x0,
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index b033702..57a8dbb 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -78,6 +78,19 @@
 		_ret;                                                   \
 	})
 
+static u32 ufs_query_desc_max_size[] = {
+	QUERY_DESC_DEVICE_MAX_SIZE,
+	QUERY_DESC_CONFIGURAION_MAX_SIZE,
+	QUERY_DESC_UNIT_MAX_SIZE,
+	QUERY_DESC_RFU_MAX_SIZE,
+	QUERY_DESC_INTERCONNECT_MAX_SIZE,
+	QUERY_DESC_STRING_MAX_SIZE,
+	QUERY_DESC_RFU_MAX_SIZE,
+	QUERY_DESC_GEOMETRY_MAZ_SIZE,
+	QUERY_DESC_POWER_MAX_SIZE,
+	QUERY_DESC_RFU_MAX_SIZE,
+};
+
 enum {
 	UFSHCD_MAX_CHANNEL	= 0,
 	UFSHCD_MAX_ID		= 1,
@@ -124,8 +137,6 @@ static void ufshcd_tmc_handler(struct ufs_hba *hba);
 static void ufshcd_async_scan(void *data, async_cookie_t cookie);
 static int ufshcd_reset_and_restore(struct ufs_hba *hba);
 static int ufshcd_clear_tm_cmd(struct ufs_hba *hba, int tag);
-static int ufshcd_read_sdev_qdepth(struct ufs_hba *hba,
-					struct scsi_device *sdev);
 
 /*
  * ufshcd_wait_for_register - wait for register value to change
@@ -1393,6 +1404,115 @@ out:
 }
 
 /**
+ * ufshcd_read_desc_param - read the specified descriptor parameter
+ * @hba: Pointer to adapter instance
+ * @desc_id: descriptor idn value
+ * @desc_index: descriptor index
+ * @param_offset: offset of the parameter to read
+ * @param_read_buf: pointer to buffer where parameter would be read
+ * @param_size: sizeof(param_read_buf)
+ *
+ * Return 0 in case of success, non-zero otherwise
+ */
+static int ufshcd_read_desc_param(struct ufs_hba *hba,
+				  enum desc_idn desc_id,
+				  int desc_index,
+				  u32 param_offset,
+				  u8 *param_read_buf,
+				  u32 param_size)
+{
+	int ret;
+	u8 *desc_buf;
+	u32 buff_len;
+	bool is_kmalloc = true;
+
+	/* safety checks */
+	if (desc_id >= QUERY_DESC_IDN_MAX)
+		return -EINVAL;
+
+	buff_len = ufs_query_desc_max_size[desc_id];
+	if ((param_offset + param_size) > buff_len)
+		return -EINVAL;
+
+	if (!param_offset && (param_size == buff_len)) {
+		/* memory space already available to hold full descriptor */
+		desc_buf = param_read_buf;
+		is_kmalloc = false;
+	} else {
+		/* allocate memory to hold full descriptor */
+		desc_buf = kmalloc(buff_len, GFP_KERNEL);
+		if (!desc_buf)
+			return -ENOMEM;
+	}
+
+	ret = ufshcd_query_descriptor(hba, UPIU_QUERY_OPCODE_READ_DESC,
+				      desc_id, desc_index, 0, desc_buf,
+				      &buff_len);
+
+	if (ret || (buff_len < ufs_query_desc_max_size[desc_id]) ||
+	    (desc_buf[QUERY_DESC_LENGTH_OFFSET] !=
+	     ufs_query_desc_max_size[desc_id])
+	    || (desc_buf[QUERY_DESC_DESC_TYPE_OFFSET] != desc_id)) {
+		dev_err(hba->dev, "%s: Failed reading descriptor. desc_id %d param_offset %d buff_len %d ret %d",
+			__func__, desc_id, param_offset, buff_len, ret);
+		if (!ret)
+			ret = -EINVAL;
+
+		goto out;
+	}
+
+	if (is_kmalloc)
+		memcpy(param_read_buf, &desc_buf[param_offset], param_size);
+out:
+	if (is_kmalloc)
+		kfree(desc_buf);
+	return ret;
+}
+
+static inline int ufshcd_read_desc(struct ufs_hba *hba,
+				   enum desc_idn desc_id,
+				   int desc_index,
+				   u8 *buf,
+				   u32 size)
+{
+	return ufshcd_read_desc_param(hba, desc_id, desc_index, 0, buf, size);
+}
+
+static inline int ufshcd_read_power_desc(struct ufs_hba *hba,
+					 u8 *buf,
+					 u32 size)
+{
+	return ufshcd_read_desc(hba, QUERY_DESC_IDN_POWER, 0, buf, size);
+}
+
+/**
+ * ufshcd_read_unit_desc_param - read the specified unit descriptor parameter
+ * @hba: Pointer to adapter instance
+ * @lun: lun id
+ * @param_offset: offset of the parameter to read
+ * @param_read_buf: pointer to buffer where parameter would be read
+ * @param_size: sizeof(param_read_buf)
+ *
+ * Return 0 in case of success, non-zero otherwise
+ */
+static inline int ufshcd_read_unit_desc_param(struct ufs_hba *hba,
+					      int lun,
+					      enum unit_desc_param param_offset,
+					      u8 *param_read_buf,
+					      u32 param_size)
+{
+	/*
+	 * Unit descriptors are only available for general purpose LUs (LUN id
+	 * from 0 to 7) and RPMB Well known LU.
+	 */
+	if (lun >= UFS_UPIU_MAX_GENERAL_LUN)
+		return -EOPNOTSUPP;
+
+	return ufshcd_read_desc_param(hba, QUERY_DESC_IDN_UNIT, lun,
+				      param_offset, param_read_buf, param_size);
+}
+
+/**
  * ufshcd_memory_alloc - allocate memory for host memory space data structures
  * @hba: per adapter instance
  *
@@ -2011,7 +2131,8 @@ static int ufshcd_verify_dev_init(struct ufs_hba *hba)
 static int ufshcd_slave_alloc(struct scsi_device *sdev)
 {
 	struct ufs_hba *hba;
-	int lun_qdepth;
+	u8 lun_qdepth;
+	int ret;
 
 	hba = shost_priv(sdev->host);
 	sdev->tagged_supported = 1;
@@ -2026,8 +2147,12 @@ static int ufshcd_slave_alloc(struct scsi_device *sdev)
 	/* REPORT SUPPORTED OPERATION CODES is not supported */
 	sdev->no_report_opcodes = 1;
 
-	lun_qdepth = ufshcd_read_sdev_qdepth(hba, sdev);
-	if (lun_qdepth <= 0)
+	ret = ufshcd_read_unit_desc_param(hba,
+					  sdev->lun,
+					  UNIT_DESC_PARAM_LU_Q_DEPTH,
+					  &lun_qdepth,
+					  sizeof(lun_qdepth));
+	if (!ret || !lun_qdepth)
 		/* eventually, we can figure out the real queue depth */
 		lun_qdepth = hba->nutrs;
 	else
@@ -3118,38 +3243,6 @@ static int ufshcd_eh_host_reset_handler(struct scsi_cmnd *cmd)
 }
 
 /**
- * ufshcd_read_sdev_qdepth - read the lun command queue depth
- * @hba: Pointer to adapter instance
- * @sdev: pointer to SCSI device
- *
- * Return in case of success the lun's queue depth else error.
- */
-static int ufshcd_read_sdev_qdepth(struct ufs_hba *hba,
-				struct scsi_device *sdev)
-{
-	int ret;
-	int buff_len = UNIT_DESC_MAX_SIZE;
-	u8 desc_buf[UNIT_DESC_MAX_SIZE];
-
-	ret = ufshcd_query_descriptor(hba, UPIU_QUERY_OPCODE_READ_DESC,
-			QUERY_DESC_IDN_UNIT, sdev->lun, 0, desc_buf, &buff_len);
-
-	if (ret || (buff_len < UNIT_DESC_PARAM_LU_Q_DEPTH)) {
-		dev_err(hba->dev,
-			"%s:Failed reading unit descriptor. len = %d ret = %d"
-			, __func__, buff_len, ret);
-		if (!ret)
-			ret = -EINVAL;
-
-		goto out;
-	}
-
-	ret = desc_buf[UNIT_DESC_PARAM_LU_Q_DEPTH] & 0xFF;
-out:
-	return ret;
-}
-
-/**
  * ufshcd_async_scan - asynchronous execution for link startup
  * @data: data pointer to pass to this function
  * @cookie: cookie data
-- 
1.8.5.2
-- 
QUALCOMM ISRAEL, on behalf of Qualcomm Innovation Center, Inc. is a member
of Code Aurora Forum, hosted by The Linux Foundation

[PATCH/RFC V2 05/16] scsi: ufs: improve init sequence

[Dolev Raviv]

From: Sujit Reddy Thumma <sthumma@codeaurora.org>

In ->hce_enable_notify() callback the vendor specific initialization
may carry out additional DME configuration using UIC commands and
hence the UIC command completion interrupt enable bit should be set
before the post reset notification.
Add retries if the link-startup fails. This is required since due to
hardware timing issues, the Uni-Pro link-startup might fail. The UFS
HCI recovery procedure contradicts the Uni-Pro sequence. The UFS HCI
specifies to resend DME_LINKSTARTUP command after IS.ULLS (link-lost
interrupt) is received. The Uni-Pro specifies that if link-startup
fails the link is in "down" state. The link-lost is indicated to the
DME user only when the link is up. Hence, the UFS HCI recovery procedure
of waiting for IS.ULLS and retrying link-startup may not work properly.

At the end, if detection fails, power off (disable clocks, regulators,
phy) if the UFS device detection fails. This saves power while UFS device
is not embedded into the system.

Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 57a8dbb..1fabff4 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -62,6 +62,12 @@
 /* Task management command timeout */
 #define TM_CMD_TIMEOUT	100 /* msecs */
 
+/* maximum number of link-startup retries */
+#define DME_LINKSTARTUP_RETRIES 3
+
+/* maximum number of reset retries before giving up */
+#define MAX_HOST_RESET_RETRIES 5
+
 /* Expose the flag value from utp_upiu_query.value */
 #define MASK_QUERY_UPIU_FLAG_LOC 0xFF
 
@@ -137,6 +143,8 @@ static void ufshcd_tmc_handler(struct ufs_hba *hba);
 static void ufshcd_async_scan(void *data, async_cookie_t cookie);
 static int ufshcd_reset_and_restore(struct ufs_hba *hba);
 static int ufshcd_clear_tm_cmd(struct ufs_hba *hba, int tag);
+static void ufshcd_hba_exit(struct ufs_hba *hba);
+static int ufshcd_probe_hba(struct ufs_hba *hba);
 
 /*
  * ufshcd_wait_for_register - wait for register value to change
@@ -2043,6 +2051,9 @@ static int ufshcd_hba_enable(struct ufs_hba *hba)
 		msleep(5);
 	}
 
+	/* enable UIC related interrupts */
+	ufshcd_enable_intr(hba, UIC_COMMAND_COMPL);
+
 	if (hba->vops && hba->vops->hce_enable_notify)
 		hba->vops->hce_enable_notify(hba, POST_CHANGE);
 
@@ -2058,23 +2069,33 @@ static int ufshcd_hba_enable(struct ufs_hba *hba)
 static int ufshcd_link_startup(struct ufs_hba *hba)
 {
 	int ret;
+	int retries = DME_LINKSTARTUP_RETRIES;
 
-	/* enable UIC related interrupts */
-	ufshcd_enable_intr(hba, UIC_COMMAND_COMPL);
+	do {
+		if (hba->vops && hba->vops->link_startup_notify)
+			hba->vops->link_startup_notify(hba, PRE_CHANGE);
 
-	if (hba->vops && hba->vops->link_startup_notify)
-		hba->vops->link_startup_notify(hba, PRE_CHANGE);
+		ret = ufshcd_dme_link_startup(hba);
 
-	ret = ufshcd_dme_link_startup(hba);
-	if (ret)
-		goto out;
+		/* check if device is detected by inter-connect layer */
+		if (!ret && !ufshcd_is_device_present(hba)) {
+			dev_err(hba->dev, "%s: Device not present\n", __func__);
+			ret = -ENXIO;
+			goto out;
+		}
+
+		/*
+		 * DME link lost indication is only received when link is up,
+		 * but we can't be sure if the link is up until link startup
+		 * succeeds. So reset the local Uni-Pro and try again.
+		 */
+		if (ret && ufshcd_hba_enable(hba))
+			goto out;
+	} while (ret && retries--);
 
-	/* check if device is detected by inter-connect layer */
-	if (!ufshcd_is_device_present(hba)) {
-		dev_err(hba->dev, "%s: Device not present\n", __func__);
-		ret = -ENXIO;
+	if (ret)
+		/* failed to get the link up... retire */
 		goto out;
-	}
 
 	/* Include any host controller configuration via UIC commands */
 	if (hba->vops && hba->vops->link_startup_notify) {
@@ -3139,7 +3160,6 @@ out:
 static int ufshcd_host_reset_and_restore(struct ufs_hba *hba)
 {
 	int err;
-	async_cookie_t cookie;
 	unsigned long flags;
 
 	/* Reset the host controller */
@@ -3152,10 +3172,9 @@ static int ufshcd_host_reset_and_restore(struct ufs_hba *hba)
 		goto out;
 
 	/* Establish the link again and restore the device */
-	cookie = async_schedule(ufshcd_async_scan, hba);
-	/* wait for async scan to be completed */
-	async_synchronize_cookie(++cookie);
-	if (hba->ufshcd_state != UFSHCD_STATE_OPERATIONAL)
+	err = ufshcd_probe_hba(hba);
+
+	if (!err && (hba->ufshcd_state != UFSHCD_STATE_OPERATIONAL))
 		err = -EIO;
 out:
 	if (err)
@@ -3177,8 +3196,11 @@ static int ufshcd_reset_and_restore(struct ufs_hba *hba)
 {
 	int err = 0;
 	unsigned long flags;
+	int retries = MAX_HOST_RESET_RETRIES;
 
-	err = ufshcd_host_reset_and_restore(hba);
+	do {
+		err = ufshcd_host_reset_and_restore(hba);
+	} while (err && --retries);
 
 	/*
 	 * After reset the door-bell might be cleared, complete
@@ -3243,13 +3265,13 @@ static int ufshcd_eh_host_reset_handler(struct scsi_cmnd *cmd)
 }
 
 /**
- * ufshcd_async_scan - asynchronous execution for link startup
- * @data: data pointer to pass to this function
- * @cookie: cookie data
+ * ufshcd_probe_hba - probe hba to detect device and initialize
+ * @hba: per-adapter instance
+ *
+ * Execute link-startup and verify device initialization
  */
-static void ufshcd_async_scan(void *data, async_cookie_t cookie)
+static int ufshcd_probe_hba(struct ufs_hba *hba)
 {
-	struct ufs_hba *hba = (struct ufs_hba *)data;
 	int ret;
 
 	ret = ufshcd_link_startup(hba);
@@ -3275,7 +3297,26 @@ static void ufshcd_async_scan(void *data, async_cookie_t cookie)
 		pm_runtime_put_sync(hba->dev);
 	}
 out:
-	return;
+	/*
+	 * If we failed to initialize the device or the device is not
+	 * present, turn off the power/clocks etc.
+	 */
+	if (ret && !ufshcd_eh_in_progress(hba))
+		ufshcd_hba_exit(hba);
+
+	return ret;
+}
+
+/**
+ * ufshcd_async_scan - asynchronous execution for probing hba
+ * @data: data pointer to pass to this function
+ * @cookie: cookie data
+ */
+static void ufshcd_async_scan(void *data, async_cookie_t cookie)
+{
+	struct ufs_hba *hba = (struct ufs_hba *)data;
+
+	ufshcd_probe_hba(hba);
 }
 
 static struct scsi_host_template ufshcd_driver_template = {
@@ -3596,6 +3637,7 @@ static int ufshcd_hba_init(struct ufs_hba *hba)
 	if (err)
 		goto out_disable_vreg;
 
+	hba->is_powered = true;
 	goto out;
 
 out_disable_vreg:
@@ -3608,9 +3650,12 @@ out:
 
 static void ufshcd_hba_exit(struct ufs_hba *hba)
 {
-	ufshcd_variant_hba_exit(hba);
-	ufshcd_setup_vreg(hba, false);
-	ufshcd_setup_clocks(hba, false);
+	if (hba->is_powered) {
+		ufshcd_variant_hba_exit(hba);
+		ufshcd_setup_vreg(hba, false);
+		ufshcd_setup_clocks(hba, false);
+		hba->is_powered = false;
+	}
 }
 
 /**
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index bc0f7ed..eddb3f3 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -228,6 +228,7 @@ struct ufs_hba_variant_ops {
  * @eh_flags: Error handling flags
  * @intr_mask: Interrupt Mask Bits
  * @ee_ctrl_mask: Exception event control mask
+ * @is_powered: flag to check if HBA is powered
  * @eh_work: Worker to handle UFS errors that require s/w attention
  * @eeh_work: Worker to handle exception events
  * @errors: HBA errors
@@ -283,6 +284,7 @@ struct ufs_hba {
 	u32 eh_flags;
 	u32 intr_mask;
 	u16 ee_ctrl_mask;
+	bool is_powered;
 
 	/* Work Queues */
 	struct work_struct eh_work;
-- 
1.8.5.2
-- 
QUALCOMM ISRAEL, on behalf of Qualcomm Innovation Center, Inc. is a member
of Code Aurora Forum, hosted by The Linux Foundation

[PATCH/RFC V2 06/16] scsi: ufs: Active Power Mode - configuring bActiveICCLevel

[Dolev Raviv]

From: Yaniv Gardi <ygardi@codeaurora.org>

The maximum power consumption in active is determined by bActiveICCLevel.
The configuration is done by reading max current supported by the
regulators connected to VCC, VCCQ and VCCQ2 rails on the boards, and
reading the current consumption levels from the device for each rails
(vcc/vccq/vccq2) using power descriptor.
We configure the bActiveICCLevel attribute, with the max value that
correspond to the minimum-of(VCC-current-level,VCCQ-current-level,
VCCQ2-current-level).
In order to minimize resume latency, pre-fetch icc levels and reference
clock during initialization and avoid reading them each link startup
during resume.

Signed-off-by: Raviv Shvili <rshvili@codeaurora.org>
Signed-off-by: Yaniv Gardi <ygardi@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>

diff --git a/drivers/scsi/ufs/ufs.h b/drivers/scsi/ufs/ufs.h
index 7ea8e71..b0e1f62 100644
--- a/drivers/scsi/ufs/ufs.h
+++ b/drivers/scsi/ufs/ufs.h
@@ -115,6 +115,7 @@ enum flag_idn {
 
 /* Attribute idn for Query requests */
 enum attr_idn {
+	QUERY_ATTR_IDN_ACTIVE_ICC_LVL	= 0x03,
 	QUERY_ATTR_IDN_BKOPS_STATUS	= 0x05,
 	QUERY_ATTR_IDN_EE_CONTROL	= 0x0D,
 	QUERY_ATTR_IDN_EE_STATUS	= 0x0E,
@@ -174,6 +175,31 @@ enum unit_desc_param {
 	UNIT_DESC_PARAM_LARGE_UNIT_SIZE_M1	= 0x22,
 };
 
+/* bActiveICCLevel parameter current units */
+enum {
+	UFSHCD_NANO_AMP		= 0,
+	UFSHCD_MICRO_AMP	= 1,
+	UFSHCD_MILI_AMP		= 2,
+	UFSHCD_AMP		= 3,
+};
+
+#define POWER_DESC_MAX_SIZE			0x62
+#define POWER_DESC_MAX_ACTV_ICC_LVLS		16
+
+/* Attribute  bActiveICCLevel parameter bit masks definitions */
+#define ATTR_ICC_LVL_UNIT_OFFSET	14
+#define ATTR_ICC_LVL_UNIT_MASK		(0x3 << ATTR_ICC_LVL_UNIT_OFFSET)
+#define ATTR_ICC_LVL_VALUE_MASK		0x3FF
+
+/* Power descriptor parameters offsets in bytes */
+enum power_desc_param_offset {
+	PWR_DESC_LEN			= 0x0,
+	PWR_DESC_TYPE			= 0x1,
+	PWR_DESC_ACTIVE_LVLS_VCC_0	= 0x2,
+	PWR_DESC_ACTIVE_LVLS_VCCQ_0	= 0x22,
+	PWR_DESC_ACTIVE_LVLS_VCCQ2_0	= 0x42,
+};
+
 /* Exception event mask values */
 enum {
 	MASK_EE_STATUS		= 0xFFFF,
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 1fabff4..a851323 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -3265,6 +3265,125 @@ static int ufshcd_eh_host_reset_handler(struct scsi_cmnd *cmd)
 }
 
 /**
+ * ufshcd_get_max_icc_level - calculate the ICC level
+ * @sup_curr_uA: max. current supported by the regulator
+ * @start_scan: row at the desc table to start scan from
+ * @buff: power descriptor buffer
+ *
+ * Returns calculated max ICC level for specific regulator
+ */
+static u32 ufshcd_get_max_icc_level(int sup_curr_uA, u32 start_scan, char *buff)
+{
+	int i;
+	int curr_uA;
+	u16 data;
+	u16 unit;
+
+	for (i = start_scan; i >= 0; i--) {
+		data = be16_to_cpu(*((u16 *)(buff + 2*i)));
+		unit = (data & ATTR_ICC_LVL_UNIT_MASK) >>
+						ATTR_ICC_LVL_UNIT_OFFSET;
+		curr_uA = data & ATTR_ICC_LVL_VALUE_MASK;
+		switch (unit) {
+		case UFSHCD_NANO_AMP:
+			curr_uA = curr_uA / 1000;
+			break;
+		case UFSHCD_MILI_AMP:
+			curr_uA = curr_uA * 1000;
+			break;
+		case UFSHCD_AMP:
+			curr_uA = curr_uA * 1000 * 1000;
+			break;
+		case UFSHCD_MICRO_AMP:
+		default:
+			break;
+		}
+		if (sup_curr_uA >= curr_uA)
+			break;
+	}
+	if (i < 0) {
+		i = 0;
+		pr_err("%s: Couldn't find valid icc_level = %d", __func__, i);
+	}
+
+	return (u32)i;
+}
+
+/**
+ * ufshcd_calc_icc_level - calculate the max ICC level
+ * In case regulators are not initialized we'll return 0
+ * @hba: per-adapter instance
+ * @desc_buf: power descriptor buffer to extract ICC levels from.
+ * @len: length of desc_buff
+ *
+ * Returns calculated ICC level
+ */
+static u32 ufshcd_find_max_sup_active_icc_level(struct ufs_hba *hba,
+							u8 *desc_buf, int len)
+{
+	u32 icc_level = 0;
+
+	if (!hba->vreg_info.vcc || !hba->vreg_info.vccq ||
+						!hba->vreg_info.vccq2) {
+		dev_err(hba->dev,
+			"%s: Regulator capability was not set, actvIccLevel=%d",
+							__func__, icc_level);
+		goto out;
+	}
+
+	if (hba->vreg_info.vcc)
+		icc_level = ufshcd_get_max_icc_level(
+				hba->vreg_info.vcc->max_uA,
+				POWER_DESC_MAX_ACTV_ICC_LVLS - 1,
+				&desc_buf[PWR_DESC_ACTIVE_LVLS_VCC_0]);
+
+	if (hba->vreg_info.vccq)
+		icc_level = ufshcd_get_max_icc_level(
+				hba->vreg_info.vccq->max_uA,
+				icc_level,
+				&desc_buf[PWR_DESC_ACTIVE_LVLS_VCCQ_0]);
+
+	if (hba->vreg_info.vccq2)
+		icc_level = ufshcd_get_max_icc_level(
+				hba->vreg_info.vccq2->max_uA,
+				icc_level,
+				&desc_buf[PWR_DESC_ACTIVE_LVLS_VCCQ2_0]);
+out:
+	return icc_level;
+}
+
+static void ufshcd_init_icc_levels(struct ufs_hba *hba)
+{
+	int ret;
+	int buff_len = QUERY_DESC_POWER_MAX_SIZE;
+	u8 desc_buf[QUERY_DESC_POWER_MAX_SIZE];
+
+	ret = ufshcd_read_power_desc(hba, desc_buf, buff_len);
+	if (ret) {
+		dev_err(hba->dev,
+			"%s: Failed reading power descriptor.len = %d ret = %d",
+			__func__, buff_len, ret);
+		return;
+	}
+
+	hba->init_prefetch_data.icc_level =
+			ufshcd_find_max_sup_active_icc_level(hba,
+			desc_buf, buff_len);
+	dev_dbg(hba->dev, "%s: setting icc_level 0x%x",
+			__func__, hba->init_prefetch_data.icc_level);
+
+	ret = ufshcd_query_attr(hba, UPIU_QUERY_OPCODE_WRITE_ATTR,
+			QUERY_ATTR_IDN_ACTIVE_ICC_LVL, 0, 0,
+			&hba->init_prefetch_data.icc_level);
+
+	if (ret)
+		dev_err(hba->dev,
+			"%s: Failed configuring bActiveICCLevel = %d ret = %d",
+			__func__, hba->init_prefetch_data.icc_level , ret);
+
+}
+
+/**
  * ufshcd_probe_hba - probe hba to detect device and initialize
  * @hba: per-adapter instance
  *
@@ -3293,9 +3412,16 @@ static int ufshcd_probe_hba(struct ufs_hba *hba)
 
 	/* If we are in error handling context no need to scan the host */
 	if (!ufshcd_eh_in_progress(hba)) {
+		if (!hba->is_init_prefetch)
+			ufshcd_init_icc_levels(hba);
+
 		scsi_scan_host(hba->host);
 		pm_runtime_put_sync(hba->dev);
 	}
+
+	if (!hba->is_init_prefetch)
+		hba->is_init_prefetch = true;
+
 out:
 	/*
 	 * If we failed to initialize the device or the device is not
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index eddb3f3..8365ad4 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -196,6 +196,15 @@ struct ufs_hba_variant_ops {
 };
 
 /**
+ * struct ufs_init_prefetch - contains data that is pre-fetched once during
+ * initialization
+ * @icc_level: icc level which was read during initialization
+ */
+struct ufs_init_prefetch {
+	u32 icc_level;
+};
+
+/**
  * struct ufs_hba - per adapter private structure
  * @mmio_base: UFSHCI base register address
  * @ucdl_base_addr: UFS Command Descriptor base address
@@ -229,6 +238,8 @@ struct ufs_hba_variant_ops {
  * @intr_mask: Interrupt Mask Bits
  * @ee_ctrl_mask: Exception event control mask
  * @is_powered: flag to check if HBA is powered
+ * @is_init_prefetch: flag to check if data was pre-fetched in initialization
+ * @init_prefetch_data: data pre-fetched during initialization
  * @eh_work: Worker to handle UFS errors that require s/w attention
  * @eeh_work: Worker to handle exception events
  * @errors: HBA errors
@@ -285,6 +296,8 @@ struct ufs_hba {
 	u32 intr_mask;
 	u16 ee_ctrl_mask;
 	bool is_powered;
+	bool is_init_prefetch;
+	struct ufs_init_prefetch init_prefetch_data;
 
 	/* Work Queues */
 	struct work_struct eh_work;
-- 
1.8.5.2
-- 
QUALCOMM ISRAEL, on behalf of Qualcomm Innovation Center, Inc. is a member
of Code Aurora Forum, hosted by The Linux Foundation

[PATCH/RFC V2 07/16] scsi: support well known logical units

[Dolev Raviv]

From: Subhash Jadavani <subhashj@codeaurora.org>

REPORT LUNS command has "SELECT REPORT" field which controls what type of
logical units to be reported by device server. According to UFS device
standard, if this field is set to 0, REPORT LUNS would report only report
standard logical units. If it's set to 1 then it would report only well
known logical unit and if it's set to 2 then device would report both
standard and well known logical units.
Some well-known logical units might not have scsi upper-layer drivers. In
such cases, the runtime PM reference count increased during device
enumeration will not be decreased, causing the parent device (host) to
always be on even during idle.

This change allows the SCSI LLD (Low Level Driver) to choose which type
of logical units should be detected.

Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>

diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c
index 4a6e4ba..5a0e164 100644
--- a/drivers/scsi/scsi_scan.c
+++ b/drivers/scsi/scsi_scan.c
@@ -802,6 +802,14 @@ static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result,
 	} else {
 		sdev->type = (inq_result[0] & 0x1f);
 		sdev->removable = (inq_result[1] & 0x80) >> 7;
+
+		/*
+		 * some devices may respond with wrong type for
+		 * well-known logical units. Force well-known type
+		 * to enumerate them correctly.
+		 */
+		if (scsi_is_wlun(sdev->lun) && (sdev->type != TYPE_WLUN))
+			sdev->type = TYPE_WLUN;
 	}
 
 	switch (sdev->type) {
@@ -817,6 +825,7 @@ static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result,
 	case TYPE_COMM:
 	case TYPE_RAID:
 	case TYPE_OSD:
+	case TYPE_WLUN:
 		sdev->writeable = 1;
 		break;
 	case TYPE_ROM:
@@ -1412,6 +1421,13 @@ static int scsi_report_lun_scan(struct scsi_target *starget, int bflags,
 	 */
 	memset(&scsi_cmd[1], 0, 5);
 
+	if (shost->report_wlus)
+		/*
+		 * Set "SELECT REPORT" field to 0x2 which will make device to
+		 * report well known logical units along with standard LUs.
+		 */
+		scsi_cmd[2] = 0x2;
+
 	/*
 	 * bytes 6 - 9: length of the command.
 	 */
diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c
index 5f36788..ba9d0f0 100644
--- a/drivers/scsi/scsi_sysfs.c
+++ b/drivers/scsi/scsi_sysfs.c
@@ -1060,6 +1060,13 @@ int scsi_sysfs_add_sdev(struct scsi_device *sdev)
 		}
 	}
 
+	/*
+	 * put runtime pm reference for well-known logical units,
+	 * drivers are expected to _get_* again during probe.
+	 */
+	if (scsi_is_wlun(sdev->lun))
+		scsi_autopm_put_device(sdev);
+
 	return error;
 }
 
diff --git a/include/scsi/scsi.h b/include/scsi/scsi.h
index 91e2e42..6a9b102 100644
--- a/include/scsi/scsi.h
+++ b/include/scsi/scsi.h
@@ -332,6 +332,7 @@ static inline int scsi_status_is_good(int status)
 #define TYPE_ENCLOSURE      0x0d    /* Enclosure Services Device */
 #define TYPE_RBC	    0x0e
 #define TYPE_OSD            0x11
+#define TYPE_WLUN           0x1e    /* well-known logical unit */
 #define TYPE_NO_LUN         0x7f
 
 /* SCSI protocols; these are taken from SPC-3 section 7.5 */
diff --git a/include/scsi/scsi_host.h b/include/scsi/scsi_host.h
index b2bc519..05664c4 100644
--- a/include/scsi/scsi_host.h
+++ b/include/scsi/scsi_host.h
@@ -675,6 +675,11 @@ struct Scsi_Host {
 	unsigned no_write_same:1;
 
 	/*
+	 * Set "SELECT REPORT" field to allow detection of well known logical
+	 * units along with standard LUs.
+	 */
+	unsigned report_wlus:1;
+	/*
 	 * Optional work queue to be utilized by the transport
 	 */
 	char work_q_name[20];
-- 
1.8.5.2
-- 
QUALCOMM ISRAEL, on behalf of Qualcomm Innovation Center, Inc. is a member
of Code Aurora Forum, hosted by The Linux Foundation

Re: [PATCH/RFC V2 07/16] scsi: support well known logical units

[Christoph Hellwig]

On Thu, Aug 14, 2014 at 04:30:58PM +0300, Dolev Raviv wrote:
> From: Subhash Jadavani <subhashj@codeaurora.org>
> 
> REPORT LUNS command has "SELECT REPORT" field which controls what type of
> logical units to be reported by device server. According to UFS device
> standard, if this field is set to 0, REPORT LUNS would report only report
> standard logical units. If it's set to 1 then it would report only well
> known logical unit and if it's set to 2 then device would report both
> standard and well known logical units.
> Some well-known logical units might not have scsi upper-layer drivers. In
> such cases, the runtime PM reference count increased during device
> enumeration will not be decreased, causing the parent device (host) to
> always be on even during idle.
> 
> This change allows the SCSI LLD (Low Level Driver) to choose which type
> of logical units should be detected.
> 
> Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
> Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
> Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
> 
> diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c
> index 4a6e4ba..5a0e164 100644
> --- a/drivers/scsi/scsi_scan.c
> +++ b/drivers/scsi/scsi_scan.c
> @@ -802,6 +802,14 @@ static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result,
>  	} else {
>  		sdev->type = (inq_result[0] & 0x1f);
>  		sdev->removable = (inq_result[1] & 0x80) >> 7;
> +
> +		/*
> +		 * some devices may respond with wrong type for
> +		 * well-known logical units. Force well-known type
> +		 * to enumerate them correctly.
> +		 */
> +		if (scsi_is_wlun(sdev->lun) && (sdev->type != TYPE_WLUN))
> +			sdev->type = TYPE_WLUN;

no need to test for TYPE_WLUN here.

>  	switch (sdev->type) {
> @@ -817,6 +825,7 @@ static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result,
>  	case TYPE_COMM:
>  	case TYPE_RAID:
>  	case TYPE_OSD:
> +	case TYPE_WLUN:
>  		sdev->writeable = 1;
>  		break;
>  	case TYPE_ROM:

This switch statements has been removed in 3.17-rc1, please rebase your
series on top of it.  While you're at it please make this patch, which
introduceѕ core scsi changes first in the series.

> @@ -1412,6 +1421,13 @@ static int scsi_report_lun_scan(struct scsi_target *starget, int bflags,
>  	 */
>  	memset(&scsi_cmd[1], 0, 5);
>  
> +	if (shost->report_wlus)
> +		/*
> +		 * Set "SELECT REPORT" field to 0x2 which will make device to
> +		 * report well known logical units along with standard LUs.
> +		 */
> +		scsi_cmd[2] = 0x2;

So we're finally getting well known LUN support.  I think we should key this
off the SBC compliance level and not have the drivers opt in.

> diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c
> index 5f36788..ba9d0f0 100644
> --- a/drivers/scsi/scsi_sysfs.c
> +++ b/drivers/scsi/scsi_sysfs.c
> @@ -1060,6 +1060,13 @@ int scsi_sysfs_add_sdev(struct scsi_device *sdev)
>  		}
>  	}
>  
> +	/*
> +	 * put runtime pm reference for well-known logical units,
> +	 * drivers are expected to _get_* again during probe.
> +	 */
> +	if (scsi_is_wlun(sdev->lun))
> +		scsi_autopm_put_device(sdev);

Special casing the well known LUNs here seems wrong.  Shouldn't we do this
for any devices that don't get a driver attached to them?

Re: [PATCH/RFC V2 07/16] scsi: support well known logical units

[Martin K. Petersen]

>>>>> "Christoph" == Christoph Hellwig <hch@infradead.org> writes:

>> + /*
>> + * put runtime pm reference for well-known logical units,
>> + * drivers are expected to _get_* again during probe.
>> + */
>> + if (scsi_is_wlun(sdev->lun))
>> + scsi_autopm_put_device(sdev);

Christoph> Special casing the well known LUNs here seems wrong.
Christoph> Shouldn't we do this for any devices that don't get a driver
Christoph> attached to them?

That would also be my preference. Relying on WLU for this seems like a
kludge.

-- 
Martin K. Petersen	Oracle Linux Engineering

[PATCH/RFC V2 08/16] scsi: ufs: introduce well known logical unit in ufs

[Dolev Raviv]

From: Subhash Jadavani <subhashj@codeaurora.org>

UFS device may have standard LUs and LUN id could be from 0x00 to 0x7F.
UFS device specification use "Peripheral Device Addressing Format"
(SCSI SAM-5) for standard LUs.

UFS device may also have the Well Known LUs (also referred as W-LU) which
again could be from 0x00 to 0x7F. For W-LUs, UFS device specification only
allows the "Extended Addressing Format" (SCSI SAM-5) which means the W-LUNs
would start from 0xC100 onwards.

This means max. LUN number reported from UFS device could be 0xC17F hence
this patch advertise the "max_lun" as 0xC17F which will allow SCSI mid
layer to detect the W-LUs as well.

But once the W-LUs are detected, UFSHCD driver may get the commands with
SCSI LUN id upto 0xC17F but UPIU LUN id field is only 8-bit wide so it
requires the mapping of SCSI LUN id to UPIU LUN id. This patch also add
support for this mapping.

Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>

diff --git a/drivers/scsi/ufs/ufs.h b/drivers/scsi/ufs/ufs.h
index b0e1f62..bcc3a7f 100644
--- a/drivers/scsi/ufs/ufs.h
+++ b/drivers/scsi/ufs/ufs.h
@@ -49,9 +49,28 @@
 #define UPIU_HEADER_DWORD(byte3, byte2, byte1, byte0)\
 			cpu_to_be32((byte3 << 24) | (byte2 << 16) |\
 			 (byte1 << 8) | (byte0))
-
+/*
+ * UFS device may have standard LUs and LUN id could be from 0x00 to
+ * 0x7F. Standard LUs use "Peripheral Device Addressing Format".
+ * UFS device may also have the Well Known LUs (also referred as W-LU)
+ * which again could be from 0x00 to 0x7F. For W-LUs, device only use
+ * the "Extended Addressing Format" which means the W-LUNs would be
+ * from 0xc100 (SCSI_W_LUN_BASE) onwards.
+ * This means max. LUN number reported from UFS device could be 0xC17F.
+ */
+#define UFS_UPIU_MAX_UNIT_NUM_ID	0x7F
+#define UFS_MAX_LUNS		(SCSI_W_LUN_BASE + UFS_UPIU_MAX_UNIT_NUM_ID)
+#define UFS_UPIU_WLUN_ID	(1 << 7)
 #define UFS_UPIU_MAX_GENERAL_LUN	8
 
+/* Well known logical unit id in LUN field of UPIU */
+enum {
+	UFS_UPIU_REPORT_LUNS_WLUN	= 0x81,
+	UFS_UPIU_UFS_DEVICE_WLUN	= 0xD0,
+	UFS_UPIU_BOOT_WLUN		= 0xB0,
+	UFS_UPIU_RPMB_WLUN		= 0xC4,
+};
+
 /*
  * UFS Protocol Information Unit related definitions
  */
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index a851323..876d210 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -100,7 +100,6 @@ static u32 ufs_query_desc_max_size[] = {
 enum {
 	UFSHCD_MAX_CHANNEL	= 0,
 	UFSHCD_MAX_ID		= 1,
-	UFSHCD_MAX_LUNS		= 8,
 	UFSHCD_CMD_PER_LUN	= 32,
 	UFSHCD_CAN_QUEUE	= 32,
 };
@@ -902,6 +901,21 @@ static int ufshcd_compose_upiu(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
 }
 
 /**
+ * ufshcd_scsi_to_upiu_lun - maps scsi LUN to UPIU LUN
+ * @scsi_lun: scsi LUN id
+ *
+ * Returns UPIU LUN id
+ */
+static inline u8 ufshcd_scsi_to_upiu_lun(unsigned int scsi_lun)
+{
+	if (scsi_is_wlun(scsi_lun))
+		return (scsi_lun & UFS_UPIU_MAX_UNIT_NUM_ID)
+			| UFS_UPIU_WLUN_ID;
+	else
+		return scsi_lun & UFS_UPIU_MAX_UNIT_NUM_ID;
+}
+
+/**
  * ufshcd_queuecommand - main entry point for SCSI requests
  * @cmd: command from SCSI Midlayer
  * @done: call back function
@@ -959,7 +973,7 @@ static int ufshcd_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd)
 	lrbp->sense_bufflen = SCSI_SENSE_BUFFERSIZE;
 	lrbp->sense_buffer = cmd->sense_buffer;
 	lrbp->task_tag = tag;
-	lrbp->lun = cmd->device->lun;
+	lrbp->lun = ufshcd_scsi_to_upiu_lun(cmd->device->lun);
 	lrbp->intr_cmd = false;
 	lrbp->command_type = UTP_CMD_TYPE_SCSI;
 
@@ -1513,7 +1527,7 @@ static inline int ufshcd_read_unit_desc_param(struct ufs_hba *hba,
 	 * Unit descriptors are only available for general purpose LUs (LUN id
 	 * from 0 to 7) and RPMB Well known LU.
 	 */
-	if (lun >= UFS_UPIU_MAX_GENERAL_LUN)
+	if (lun != UFS_UPIU_RPMB_WLUN && (lun >= UFS_UPIU_MAX_GENERAL_LUN))
 		return -EOPNOTSUPP;
 
 	return ufshcd_read_desc_param(hba, QUERY_DESC_IDN_UNIT, lun,
@@ -2144,6 +2158,44 @@ static int ufshcd_verify_dev_init(struct ufs_hba *hba)
 }
 
 /**
+ * ufshcd_set_queue_depth - set lun queue depth
+ * @sdev: pointer to SCSI device
+ *
+ * Read bLUQueueDepth value and activate scsi tagged command
+ * queueing. For WLUN, queue depth is set to 1. For best-effort
+ * cases (bLUQueueDepth = 0) the queue depth is set to a maximum
+ * value that host can queue.
+ */
+static void ufshcd_set_queue_depth(struct scsi_device *sdev)
+{
+	int ret = 0;
+	u8 lun_qdepth;
+	struct ufs_hba *hba;
+
+	hba = shost_priv(sdev->host);
+
+	lun_qdepth = hba->nutrs;
+	ret = ufshcd_read_unit_desc_param(hba,
+					  ufshcd_scsi_to_upiu_lun(sdev->lun),
+					  UNIT_DESC_PARAM_LU_Q_DEPTH,
+					  &lun_qdepth,
+					  sizeof(lun_qdepth));
+
+	/* Some WLUN doesn't support unit descriptor */
+	if (ret == -EOPNOTSUPP)
+		lun_qdepth = 1;
+	else if (!lun_qdepth)
+		/* eventually, we can figure out the real queue depth */
+		lun_qdepth = hba->nutrs;
+	else
+		lun_qdepth = min_t(int, lun_qdepth, hba->nutrs);
+
+	dev_dbg(hba->dev, "%s: activate tcq with queue depth %d\n",
+			__func__, lun_qdepth);
+	scsi_activate_tcq(sdev, lun_qdepth);
+}
+
+/**
  * ufshcd_slave_alloc - handle initial SCSI device configurations
  * @sdev: pointer to SCSI device
  *
@@ -2152,8 +2204,6 @@ static int ufshcd_verify_dev_init(struct ufs_hba *hba)
 static int ufshcd_slave_alloc(struct scsi_device *sdev)
 {
 	struct ufs_hba *hba;
-	u8 lun_qdepth;
-	int ret;
 
 	hba = shost_priv(sdev->host);
 	sdev->tagged_supported = 1;
@@ -2168,20 +2218,8 @@ static int ufshcd_slave_alloc(struct scsi_device *sdev)
 	/* REPORT SUPPORTED OPERATION CODES is not supported */
 	sdev->no_report_opcodes = 1;
 
-	ret = ufshcd_read_unit_desc_param(hba,
-					  sdev->lun,
-					  UNIT_DESC_PARAM_LU_Q_DEPTH,
-					  &lun_qdepth,
-					  sizeof(lun_qdepth));
-	if (!ret || !lun_qdepth)
-		/* eventually, we can figure out the real queue depth */
-		lun_qdepth = hba->nutrs;
-	else
-		lun_qdepth = min_t(int, lun_qdepth, hba->nutrs);
 
-	dev_dbg(hba->dev, "%s: activate tcq with queue depth %d\n",
-			__func__, lun_qdepth);
-	scsi_activate_tcq(sdev, lun_qdepth);
+	ufshcd_set_queue_depth(sdev);
 
 	return 0;
 }
@@ -2244,6 +2282,9 @@ static void ufshcd_slave_destroy(struct scsi_device *sdev)
 
 	hba = shost_priv(sdev->host);
 	scsi_deactivate_tcq(sdev, hba->nutrs);
+	/* Drop the reference as it won't be needed anymore */
+	if (ufshcd_scsi_to_upiu_lun(sdev->lun) == UFS_UPIU_UFS_DEVICE_WLUN)
+		hba->sdev_ufs_device = NULL;
 }
 
 /**
@@ -2961,7 +3002,10 @@ static int ufshcd_issue_tm_cmd(struct ufs_hba *hba, int lun_id, int task_id,
 					      lun_id, task_tag);
 	task_req_upiup->header.dword_1 =
 		UPIU_HEADER_DWORD(0, tm_function, 0, 0);
-
+	/*
+	 * The host shall provide the same value for LUN field in the basic
+	 * header and for Input Parameter.
+	 */
 	task_req_upiup->input_param1 = cpu_to_be32(lun_id);
 	task_req_upiup->input_param2 = cpu_to_be32(task_id);
 
@@ -3980,10 +4024,11 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq)
 	host->can_queue = hba->nutrs;
 	host->cmd_per_lun = hba->nutrs;
 	host->max_id = UFSHCD_MAX_ID;
-	host->max_lun = UFSHCD_MAX_LUNS;
+	host->max_lun = UFS_MAX_LUNS;
 	host->max_channel = UFSHCD_MAX_CHANNEL;
 	host->unique_id = host->host_no;
 	host->max_cmd_len = MAX_CDB_SIZE;
+	host->report_wlus = 1;
 
 	/* Initailize wait queue for task management */
 	init_waitqueue_head(&hba->tm_wq);
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index 8365ad4..9b5f77f 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -124,7 +124,7 @@ struct ufshcd_lrb {
 
 	int command_type;
 	int task_tag;
-	unsigned int lun;
+	u8 lun; /* UPIU LUN id field is only 8-bit wide */
 	bool intr_cmd;
 };
 
@@ -266,6 +266,11 @@ struct ufs_hba {
 
 	struct Scsi_Host *host;
 	struct device *dev;
+	/*
+	 * This field is to keep a reference to "scsi_device" corresponding to
+	 * "UFS device" W-LU.
+	 */
+	struct scsi_device *sdev_ufs_device;
 
 	struct ufshcd_lrb *lrb;
 	unsigned long lrb_in_use;
-- 
1.8.5.2
-- 
QUALCOMM ISRAEL, on behalf of Qualcomm Innovation Center, Inc. is a member
of Code Aurora Forum, hosted by The Linux Foundation

[PATCH/RFC V2 09/16] scsi: sd: Avoid sending medium write commands if device is write protected

[Dolev Raviv]

From: Sujit Reddy Thumma <sthumma@codeaurora.org>

The SYNCHRONIZE_CACHE command is a medium write command and hence can
fail when the device is write protected. Avoid sending such commands by
making sure that write-cache-enable is disabled even though the device
claim to support it.

Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>

diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 3663e38..67282bf 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -185,7 +185,7 @@ cache_type_store(struct device *dev, struct device_attribute *attr,
 	if (ct < 0)
 		return -EINVAL;
 	rcd = ct & 0x01 ? 1 : 0;
-	wce = ct & 0x02 ? 1 : 0;
+	wce = (ct & 0x02) && !sdkp->write_prot ? 1 : 0;
 
 	if (sdkp->cache_override) {
 		sdkp->WCE = wce;
@@ -2493,6 +2493,10 @@ sd_read_cache_type(struct scsi_disk *sdkp, unsigned char *buffer)
 			sdkp->DPOFUA = 0;
 		}
 
+		/* No cache flush allowed for write protected devices */
+		if (sdkp->WCE && sdkp->write_prot)
+			sdkp->WCE = 0;
+
 		if (sdkp->first_scan || old_wce != sdkp->WCE ||
 		    old_rcd != sdkp->RCD || old_dpofua != sdkp->DPOFUA)
 			sd_printk(KERN_NOTICE, sdkp,
-- 
1.8.5.2
-- 
QUALCOMM ISRAEL, on behalf of Qualcomm Innovation Center, Inc. is a member
of Code Aurora Forum, hosted by The Linux Foundation

[PATCH/RFC V2 10/16] scsi: ufs: add UFS power management support

[Dolev Raviv]

From: Subhash Jadavani <subhashj@codeaurora.org>

This patch adds support for UFS device and UniPro link power management
during runtime/system PM.

Main idea is to define multiple UFS low power levels based on UFS device
and UFS link power states. This would allow any specific platform or pci
driver to choose the best suited low power level during runtime and
system suspend based on their power goals.

bkops handlig:
To put the UFS device in sleep state when bkops is disabled, first query
the bkops status from the device and enable bkops on device only if
device needs time to perform the bkops.

START_STOP handling:
Before sending START_STOP_UNIT to the device well-known logical unit
(w-lun) to make sure that the device w-lun unit attention condition is
cleared.

Write protection:
UFS device specification allows LUs to be write protected, either
permanently or power on write protected. If any LU is power on write
protected and if the card is power cycled (by powering off VCCQ and/or
VCC rails), LU's write protect status would be lost. So this means those
LUs can be written now. To ensures that UFS device is power cycled only
if the power on protect is not set for any of the LUs, check if power on
write protect is set and if device is in sleep/power-off state & link in
inactive state (Hibern8 or OFF state).
If none of the Logical Units on UFS device is power on write protected
then all UFS device power rails (VCC, VCCQ & VCCQ2) can be turned off if
UFS device is in power-off state and UFS link is in OFF state. But current
implementation would disable all device power rails even if UFS link is
not in OFF state.

Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>

diff --git a/drivers/scsi/ufs/ufs.h b/drivers/scsi/ufs/ufs.h
index bcc3a7f..2a82959 100644
--- a/drivers/scsi/ufs/ufs.h
+++ b/drivers/scsi/ufs/ufs.h
@@ -129,6 +129,7 @@ enum {
 /* Flag idn for Query Requests*/
 enum flag_idn {
 	QUERY_FLAG_IDN_FDEVICEINIT      = 0x01,
+	QUERY_FLAG_IDN_PWR_ON_WPE	= 0x03,
 	QUERY_FLAG_IDN_BKOPS_EN         = 0x04,
 };
 
@@ -194,6 +195,18 @@ enum unit_desc_param {
 	UNIT_DESC_PARAM_LARGE_UNIT_SIZE_M1	= 0x22,
 };
 
+/*
+ * Logical Unit Write Protect
+ * 00h: LU not write protected
+ * 01h: LU write protected when fPowerOnWPEn =1
+ * 02h: LU permanently write protected when fPermanentWPEn =1
+ */
+enum ufs_lu_wp_type {
+	UFS_LU_NO_WP		= 0x00,
+	UFS_LU_POWER_ON_WP	= 0x01,
+	UFS_LU_PERM_WP		= 0x02,
+};
+
 /* bActiveICCLevel parameter current units */
 enum {
 	UFSHCD_NANO_AMP		= 0,
@@ -226,11 +239,12 @@ enum {
 };
 
 /* Background operation status */
-enum {
+enum bkops_status {
 	BKOPS_STATUS_NO_OP               = 0x0,
 	BKOPS_STATUS_NON_CRITICAL        = 0x1,
 	BKOPS_STATUS_PERF_IMPACT         = 0x2,
 	BKOPS_STATUS_CRITICAL            = 0x3,
+	BKOPS_STATUS_MAX		 = BKOPS_STATUS_CRITICAL,
 };
 
 /* UTP QUERY Transaction Specific Fields OpCode */
@@ -291,6 +305,14 @@ enum {
 	UPIU_TASK_MANAGEMENT_FUNC_FAILED	= 0x05,
 	UPIU_INCORRECT_LOGICAL_UNIT_NO		= 0x09,
 };
+
+/* UFS device power modes */
+enum ufs_dev_pwr_mode {
+	UFS_ACTIVE_PWR_MODE	= 1,
+	UFS_SLEEP_PWR_MODE	= 2,
+	UFS_POWERDOWN_PWR_MODE	= 3,
+};
+
 /**
  * struct utp_upiu_header - UPIU header structure
  * @dword_0: UPIU header DW-0
@@ -437,6 +459,12 @@ struct ufs_query_res {
 #define UFS_VREG_VCCQ2_MIN_UV	   1650000 /* uV */
 #define UFS_VREG_VCCQ2_MAX_UV	   1950000 /* uV */
 
+/*
+ * VCCQ & VCCQ2 current requirement when UFS device is in sleep state
+ * and link is in Hibern8 state.
+ */
+#define UFS_VREG_LPM_LOAD_UA	1000 /* uA */
+
 struct ufs_vreg {
 	struct regulator *reg;
 	const char *name;
@@ -453,4 +481,10 @@ struct ufs_vreg_info {
 	struct ufs_vreg *vccq2;
 };
 
+struct ufs_dev_info {
+	bool f_power_on_wp_en;
+	/* Keeps information if any of the LU is power on write protected */
+	bool is_lu_power_on_wp;
+};
+
 #endif /* End of Header */
diff --git a/drivers/scsi/ufs/ufshcd-pci.c b/drivers/scsi/ufs/ufshcd-pci.c
index 1aac2ef..b8f7774 100644
--- a/drivers/scsi/ufs/ufshcd-pci.c
+++ b/drivers/scsi/ufs/ufshcd-pci.c
@@ -43,34 +43,24 @@
  * @pdev: pointer to PCI device handle
  * @state: power state
  *
- * Returns -ENOSYS
+ * Returns 0 if successful
+ * Returns non-zero otherwise
  */
 static int ufshcd_pci_suspend(struct device *dev)
 {
-	/*
-	 * TODO:
-	 * 1. Call ufshcd_suspend
-	 * 2. Do bus specific power management
-	 */
-
-	return -ENOSYS;
+	return ufshcd_system_suspend(dev_get_drvdata(dev));
 }
 
 /**
  * ufshcd_pci_resume - resume power management function
  * @pdev: pointer to PCI device handle
  *
- * Returns -ENOSYS
+ * Returns 0 if successful
+ * Returns non-zero otherwise
  */
 static int ufshcd_pci_resume(struct device *dev)
 {
-	/*
-	 * TODO:
-	 * 1. Call ufshcd_resume.
-	 * 2. Do bus specific wake up
-	 */
-
-	return -ENOSYS;
+	return ufshcd_system_resume(dev_get_drvdata(dev));
 }
 #else
 #define ufshcd_pci_suspend	NULL
@@ -80,30 +70,15 @@ static int ufshcd_pci_resume(struct device *dev)
 #ifdef CONFIG_PM_RUNTIME
 static int ufshcd_pci_runtime_suspend(struct device *dev)
 {
-	struct ufs_hba *hba = dev_get_drvdata(dev);
-
-	if (!hba)
-		return 0;
-
-	return ufshcd_runtime_suspend(hba);
+	return ufshcd_runtime_suspend(dev_get_drvdata(dev));
 }
 static int ufshcd_pci_runtime_resume(struct device *dev)
 {
-	struct ufs_hba *hba = dev_get_drvdata(dev);
-
-	if (!hba)
-		return 0;
-
-	return ufshcd_runtime_resume(hba);
+	return ufshcd_runtime_resume(dev_get_drvdata(dev));
 }
 static int ufshcd_pci_runtime_idle(struct device *dev)
 {
-	struct ufs_hba *hba = dev_get_drvdata(dev);
-
-	if (!hba)
-		return 0;
-
-	return ufshcd_runtime_idle(hba);
+	return ufshcd_runtime_idle(dev_get_drvdata(dev));
 }
 #else /* !CONFIG_PM_RUNTIME */
 #define ufshcd_pci_runtime_suspend	NULL
@@ -117,7 +92,7 @@ static int ufshcd_pci_runtime_idle(struct device *dev)
  */
 static void ufshcd_pci_shutdown(struct pci_dev *pdev)
 {
-	ufshcd_hba_stop((struct ufs_hba *)pci_get_drvdata(pdev));
+	ufshcd_shutdown((struct ufs_hba *)pci_get_drvdata(pdev));
 }
 
 /**
diff --git a/drivers/scsi/ufs/ufshcd-pltfrm.c b/drivers/scsi/ufs/ufshcd-pltfrm.c
index 642d80f..edaccd0 100644
--- a/drivers/scsi/ufs/ufshcd-pltfrm.c
+++ b/drivers/scsi/ufs/ufshcd-pltfrm.c
@@ -216,45 +216,24 @@ out:
  * ufshcd_pltfrm_suspend - suspend power management function
  * @dev: pointer to device handle
  *
- *
- * Returns 0
+ * Returns 0 if successful
+ * Returns non-zero otherwise
  */
 static int ufshcd_pltfrm_suspend(struct device *dev)
 {
-	struct platform_device *pdev = to_platform_device(dev);
-	struct ufs_hba *hba =  platform_get_drvdata(pdev);
-
-	/*
-	 * TODO:
-	 * 1. Call ufshcd_suspend
-	 * 2. Do bus specific power management
-	 */
-
-	disable_irq(hba->irq);
-
-	return 0;
+	return ufshcd_system_suspend(dev_get_drvdata(dev));
 }
 
 /**
  * ufshcd_pltfrm_resume - resume power management function
  * @dev: pointer to device handle
  *
- * Returns 0
+ * Returns 0 if successful
+ * Returns non-zero otherwise
  */
 static int ufshcd_pltfrm_resume(struct device *dev)
 {
-	struct platform_device *pdev = to_platform_device(dev);
-	struct ufs_hba *hba =  platform_get_drvdata(pdev);
-
-	/*
-	 * TODO:
-	 * 1. Call ufshcd_resume.
-	 * 2. Do bus specific wake up
-	 */
-
-	enable_irq(hba->irq);
-
-	return 0;
+	return ufshcd_system_resume(dev_get_drvdata(dev));
 }
 #else
 #define ufshcd_pltfrm_suspend	NULL
@@ -264,30 +243,15 @@ static int ufshcd_pltfrm_resume(struct device *dev)
 #ifdef CONFIG_PM_RUNTIME
 static int ufshcd_pltfrm_runtime_suspend(struct device *dev)
 {
-	struct ufs_hba *hba =  dev_get_drvdata(dev);
-
-	if (!hba)
-		return 0;
-
-	return ufshcd_runtime_suspend(hba);
+	return ufshcd_runtime_suspend(dev_get_drvdata(dev));
 }
 static int ufshcd_pltfrm_runtime_resume(struct device *dev)
 {
-	struct ufs_hba *hba =  dev_get_drvdata(dev);
-
-	if (!hba)
-		return 0;
-
-	return ufshcd_runtime_resume(hba);
+	return ufshcd_runtime_resume(dev_get_drvdata(dev));
 }
 static int ufshcd_pltfrm_runtime_idle(struct device *dev)
 {
-	struct ufs_hba *hba =  dev_get_drvdata(dev);
-
-	if (!hba)
-		return 0;
-
-	return ufshcd_runtime_idle(hba);
+	return ufshcd_runtime_idle(dev_get_drvdata(dev));
 }
 #else /* !CONFIG_PM_RUNTIME */
 #define ufshcd_pltfrm_runtime_suspend	NULL
@@ -295,6 +259,11 @@ static int ufshcd_pltfrm_runtime_idle(struct device *dev)
 #define ufshcd_pltfrm_runtime_idle	NULL
 #endif /* CONFIG_PM_RUNTIME */
 
+static void ufshcd_pltfrm_shutdown(struct platform_device *pdev)
+{
+	ufshcd_shutdown((struct ufs_hba *)platform_get_drvdata(pdev));
+}
+
 /**
  * ufshcd_pltfrm_probe - probe routine of the driver
  * @pdev: pointer to Platform device handle
@@ -395,6 +364,7 @@ static const struct dev_pm_ops ufshcd_dev_pm_ops = {
 static struct platform_driver ufshcd_pltfrm_driver = {
 	.probe	= ufshcd_pltfrm_probe,
 	.remove	= ufshcd_pltfrm_remove,
+	.shutdown = ufshcd_pltfrm_shutdown,
 	.driver	= {
 		.name	= "ufshcd",
 		.owner	= THIS_MODULE,
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 876d210..fac71c9 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -44,7 +44,6 @@
 
 #define UFSHCD_ENABLE_INTRS	(UTP_TRANSFER_REQ_COMPL |\
 				 UTP_TASK_REQ_COMPL |\
-				 UIC_POWER_MODE |\
 				 UFSHCD_ERROR_MASK)
 /* UIC command timeout, unit: ms */
 #define UIC_CMD_TIMEOUT	500
@@ -138,12 +137,63 @@ enum {
 #define ufshcd_clear_eh_in_progress(h) \
 	(h->eh_flags &= ~UFSHCD_EH_IN_PROGRESS)
 
+#define ufshcd_set_ufs_dev_active(h) \
+	((h)->curr_dev_pwr_mode = UFS_ACTIVE_PWR_MODE)
+#define ufshcd_set_ufs_dev_sleep(h) \
+	((h)->curr_dev_pwr_mode = UFS_SLEEP_PWR_MODE)
+#define ufshcd_set_ufs_dev_poweroff(h) \
+	((h)->curr_dev_pwr_mode = UFS_POWERDOWN_PWR_MODE)
+#define ufshcd_is_ufs_dev_active(h) \
+	((h)->curr_dev_pwr_mode == UFS_ACTIVE_PWR_MODE)
+#define ufshcd_is_ufs_dev_sleep(h) \
+	((h)->curr_dev_pwr_mode == UFS_SLEEP_PWR_MODE)
+#define ufshcd_is_ufs_dev_poweroff(h) \
+	((h)->curr_dev_pwr_mode == UFS_POWERDOWN_PWR_MODE)
+
+static struct ufs_pm_lvl_states ufs_pm_lvl_states[] = {
+	{UFS_ACTIVE_PWR_MODE, UIC_LINK_ACTIVE_STATE},
+	{UFS_ACTIVE_PWR_MODE, UIC_LINK_HIBERN8_STATE},
+	{UFS_SLEEP_PWR_MODE, UIC_LINK_ACTIVE_STATE},
+	{UFS_SLEEP_PWR_MODE, UIC_LINK_HIBERN8_STATE},
+	{UFS_POWERDOWN_PWR_MODE, UIC_LINK_HIBERN8_STATE},
+	{UFS_POWERDOWN_PWR_MODE, UIC_LINK_OFF_STATE},
+};
+
+static inline enum ufs_dev_pwr_mode
+ufs_get_pm_lvl_to_dev_pwr_mode(enum ufs_pm_level lvl)
+{
+	return ufs_pm_lvl_states[lvl].dev_state;
+}
+
+static inline enum uic_link_state
+ufs_get_pm_lvl_to_link_pwr_state(enum ufs_pm_level lvl)
+{
+	return ufs_pm_lvl_states[lvl].link_state;
+}
+
 static void ufshcd_tmc_handler(struct ufs_hba *hba);
 static void ufshcd_async_scan(void *data, async_cookie_t cookie);
 static int ufshcd_reset_and_restore(struct ufs_hba *hba);
 static int ufshcd_clear_tm_cmd(struct ufs_hba *hba, int tag);
 static void ufshcd_hba_exit(struct ufs_hba *hba);
 static int ufshcd_probe_hba(struct ufs_hba *hba);
+static int ufshcd_host_reset_and_restore(struct ufs_hba *hba);
+
+static inline void ufshcd_enable_irq(struct ufs_hba *hba)
+{
+	if (!hba->is_irq_enabled) {
+		enable_irq(hba->irq);
+		hba->is_irq_enabled = true;
+	}
+}
+
+static inline void ufshcd_disable_irq(struct ufs_hba *hba)
+{
+	if (hba->is_irq_enabled) {
+		disable_irq(hba->irq);
+		hba->is_irq_enabled = false;
+	}
+}
 
 /*
  * ufshcd_wait_for_register - wait for register value to change
@@ -1778,44 +1828,48 @@ out:
 EXPORT_SYMBOL_GPL(ufshcd_dme_get_attr);
 
 /**
- * ufshcd_uic_change_pwr_mode - Perform the UIC power mode chage
- *				using DME_SET primitives.
+ * ufshcd_uic_pwr_ctrl - executes UIC commands (which affects the link power
+ * state) and waits for it to take effect.
+ *
  * @hba: per adapter instance
- * @mode: powr mode value
+ * @cmd: UIC command to execute
+ *
+ * DME operations like DME_SET(PA_PWRMODE), DME_HIBERNATE_ENTER &
+ * DME_HIBERNATE_EXIT commands take some time to take its effect on both host
+ * and device UniPro link and hence it's final completion would be indicated by
+ * dedicated status bits in Interrupt Status register (UPMS, UHES, UHXS) in
+ * addition to normal UIC command completion Status (UCCS). This function only
+ * returns after the relevant status bits indicate the completion.
  *
  * Returns 0 on success, non-zero value on failure
  */
-static int ufshcd_uic_change_pwr_mode(struct ufs_hba *hba, u8 mode)
+int ufshcd_uic_pwr_ctrl(struct ufs_hba *hba, struct uic_command *cmd)
 {
-	struct uic_command uic_cmd = {0};
-	struct completion pwr_done;
+	struct completion uic_async_done;
 	unsigned long flags;
 	u8 status;
 	int ret;
 
-	uic_cmd.command = UIC_CMD_DME_SET;
-	uic_cmd.argument1 = UIC_ARG_MIB(PA_PWRMODE);
-	uic_cmd.argument3 = mode;
-	init_completion(&pwr_done);
-
 	mutex_lock(&hba->uic_cmd_mutex);
+	init_completion(&uic_async_done);
 
 	spin_lock_irqsave(hba->host->host_lock, flags);
-	hba->pwr_done = &pwr_done;
+	hba->uic_async_done = &uic_async_done;
 	spin_unlock_irqrestore(hba->host->host_lock, flags);
-	ret = __ufshcd_send_uic_cmd(hba, &uic_cmd);
+
+	ret = __ufshcd_send_uic_cmd(hba, cmd);
 	if (ret) {
 		dev_err(hba->dev,
-			"pwr mode change with mode 0x%x uic error %d\n",
-			mode, ret);
+			"pwr ctrl cmd 0x%x with mode 0x%x uic error %d\n",
+			cmd->command, cmd->argument3, ret);
 		goto out;
 	}
 
-	if (!wait_for_completion_timeout(hba->pwr_done,
+	if (!wait_for_completion_timeout(hba->uic_async_done,
 					 msecs_to_jiffies(UIC_CMD_TIMEOUT))) {
 		dev_err(hba->dev,
-			"pwr mode change with mode 0x%x completion timeout\n",
-			mode);
+			"pwr ctrl cmd 0x%x with mode 0x%x completion timeout\n",
+			cmd->command, cmd->argument3);
 		ret = -ETIMEDOUT;
 		goto out;
 	}
@@ -1823,19 +1877,62 @@ static int ufshcd_uic_change_pwr_mode(struct ufs_hba *hba, u8 mode)
 	status = ufshcd_get_upmcrs(hba);
 	if (status != PWR_LOCAL) {
 		dev_err(hba->dev,
-			"pwr mode change failed, host umpcrs:0x%x\n",
-			status);
+			"pwr ctrl cmd 0x%0x failed, host umpcrs:0x%x\n",
+			cmd->command, status);
 		ret = (status != PWR_OK) ? status : -1;
 	}
 out:
 	spin_lock_irqsave(hba->host->host_lock, flags);
-	hba->pwr_done = NULL;
+	hba->uic_async_done = NULL;
 	spin_unlock_irqrestore(hba->host->host_lock, flags);
 	mutex_unlock(&hba->uic_cmd_mutex);
 	return ret;
 }
 
 /**
+ * ufshcd_uic_change_pwr_mode - Perform the UIC power mode chage
+ *				using DME_SET primitives.
+ * @hba: per adapter instance
+ * @mode: powr mode value
+ *
+ * Returns 0 on success, non-zero value on failure
+ */
+static int ufshcd_uic_change_pwr_mode(struct ufs_hba *hba, u8 mode)
+{
+	struct uic_command uic_cmd = {0};
+
+	uic_cmd.command = UIC_CMD_DME_SET;
+	uic_cmd.argument1 = UIC_ARG_MIB(PA_PWRMODE);
+	uic_cmd.argument3 = mode;
+
+	return ufshcd_uic_pwr_ctrl(hba, &uic_cmd);
+}
+
+static int ufshcd_uic_hibern8_enter(struct ufs_hba *hba)
+{
+	struct uic_command uic_cmd = {0};
+
+	uic_cmd.command = UIC_CMD_DME_HIBER_ENTER;
+
+	return ufshcd_uic_pwr_ctrl(hba, &uic_cmd);
+}
+
+static int ufshcd_uic_hibern8_exit(struct ufs_hba *hba)
+{
+	struct uic_command uic_cmd = {0};
+	int ret;
+
+	uic_cmd.command = UIC_CMD_DME_HIBER_EXIT;
+	ret = ufshcd_uic_pwr_ctrl(hba, &uic_cmd);
+	if (ret) {
+		ufshcd_set_link_off(hba);
+		ret = ufshcd_host_reset_and_restore(hba);
+	}
+
+	return ret;
+}
+
+/**
  * ufshcd_config_max_pwr_mode - Set & Change power mode with
  *	maximum capability attribute information.
  * @hba: per adapter instance
@@ -2034,6 +2131,9 @@ static int ufshcd_hba_enable(struct ufs_hba *hba)
 		msleep(5);
 	}
 
+	/* UniPro link is disabled at this point */
+	ufshcd_set_link_off(hba);
+
 	if (hba->vops && hba->vops->hce_enable_notify)
 		hba->vops->hce_enable_notify(hba, PRE_CHANGE);
 
@@ -2066,7 +2166,7 @@ static int ufshcd_hba_enable(struct ufs_hba *hba)
 	}
 
 	/* enable UIC related interrupts */
-	ufshcd_enable_intr(hba, UIC_COMMAND_COMPL);
+	ufshcd_enable_intr(hba, UFSHCD_UIC_MASK);
 
 	if (hba->vops && hba->vops->hce_enable_notify)
 		hba->vops->hce_enable_notify(hba, POST_CHANGE);
@@ -2195,6 +2295,62 @@ static void ufshcd_set_queue_depth(struct scsi_device *sdev)
 	scsi_activate_tcq(sdev, lun_qdepth);
 }
 
+/*
+ * ufshcd_get_lu_wp - returns the "b_lu_write_protect" from UNIT DESCRIPTOR
+ * @hba: per-adapter instance
+ * @lun: UFS device lun id
+ * @b_lu_write_protect: pointer to buffer to hold the LU's write protect info
+ *
+ * Returns 0 in case of success and b_lu_write_protect status would be returned
+ * @b_lu_write_protect parameter.
+ * Returns -ENOTSUPP if reading b_lu_write_protect is not supported.
+ * Returns -EINVAL in case of invalid parameters passed to this function.
+ */
+static int ufshcd_get_lu_wp(struct ufs_hba *hba,
+			    u8 lun,
+			    u8 *b_lu_write_protect)
+{
+	int ret;
+
+	if (!b_lu_write_protect)
+		ret = -EINVAL;
+	/*
+	 * According to UFS device spec, RPMB LU can't be write
+	 * protected so skip reading bLUWriteProtect parameter for
+	 * it. For other W-LUs, UNIT DESCRIPTOR is not available.
+	 */
+	else if (lun >= UFS_UPIU_MAX_GENERAL_LUN)
+		ret = -ENOTSUPP;
+	else
+		ret = ufshcd_read_unit_desc_param(hba,
+					  lun,
+					  UNIT_DESC_PARAM_LU_WR_PROTECT,
+					  b_lu_write_protect,
+					  sizeof(*b_lu_write_protect));
+	return ret;
+}
+
+/**
+ * ufshcd_get_lu_power_on_wp_status - get LU's power on write protect
+ * status
+ * @hba: per-adapter instance
+ * @sdev: pointer to SCSI device
+ *
+ */
+static inline void ufshcd_get_lu_power_on_wp_status(struct ufs_hba *hba,
+						    struct scsi_device *sdev)
+{
+	if (hba->dev_info.f_power_on_wp_en &&
+	    !hba->dev_info.is_lu_power_on_wp) {
+		u8 b_lu_write_protect;
+
+		if (!ufshcd_get_lu_wp(hba, ufshcd_scsi_to_upiu_lun(sdev->lun),
+				      &b_lu_write_protect) &&
+		    (b_lu_write_protect == UFS_LU_POWER_ON_WP))
+			hba->dev_info.is_lu_power_on_wp = true;
+	}
+}
+
 /**
  * ufshcd_slave_alloc - handle initial SCSI device configurations
  * @sdev: pointer to SCSI device
@@ -2221,6 +2377,21 @@ static int ufshcd_slave_alloc(struct scsi_device *sdev)
 
 	ufshcd_set_queue_depth(sdev);
 
+	ufshcd_get_lu_power_on_wp_status(hba, sdev);
+
+	/*
+	 * For selecting the UFS device power mode (Active / UFS_Sleep /
+	 * UFS_PowerDown), SCSI power management command (START STOP UNIT)
+	 * needs to be sent to a "UFS device" Well known Logical Unit (W-LU).
+	 * As this command would be sent during the UFS host controller
+	 * runtime/system PM callbacks, we need a reference to "scsi_device"
+	 * associated to "UFS device" W-LU. This change saves the "scsi_device"
+	 * reference for "UFS device" W-LU during slave_configure() callback
+	 * from SCSI mid layer.
+	 */
+	if (ufshcd_scsi_to_upiu_lun(sdev->lun) == UFS_UPIU_UFS_DEVICE_WLUN)
+		hba->sdev_ufs_device = sdev;
+
 	return 0;
 }
 
@@ -2451,8 +2622,8 @@ static void ufshcd_uic_cmd_compl(struct ufs_hba *hba, u32 intr_status)
 		complete(&hba->active_uic_cmd->done);
 	}
 
-	if ((intr_status & UIC_POWER_MODE) && hba->pwr_done)
-		complete(hba->pwr_done);
+	if ((intr_status & UFSHCD_UIC_PWR_MASK) && hba->uic_async_done)
+		complete(hba->uic_async_done);
 }
 
 /**
@@ -2664,33 +2835,62 @@ static inline int ufshcd_get_bkops_status(struct ufs_hba *hba, u32 *status)
 }
 
 /**
- * ufshcd_urgent_bkops - handle urgent bkops exception event
+ * ufshcd_bkops_ctrl - control the auto bkops based on current bkops status
  * @hba: per-adapter instance
+ * @status: bkops_status value
  *
- * Enable fBackgroundOpsEn flag in the device to permit background
- * operations.
+ * Read the bkops_status from the UFS device and Enable fBackgroundOpsEn
+ * flag in the device to permit background operations if the device
+ * bkops_status is greater than or equal to "status" argument passed to
+ * this function, disable otherwise.
+ *
+ * Returns 0 for success, non-zero in case of failure.
+ *
+ * NOTE: Caller of this function can check the "hba->auto_bkops_enabled" flag
+ * to know whether auto bkops is enabled or disabled after this function
+ * returns control to it.
  */
-static int ufshcd_urgent_bkops(struct ufs_hba *hba)
+static int ufshcd_bkops_ctrl(struct ufs_hba *hba,
+			     enum bkops_status status)
 {
 	int err;
-	u32 status = 0;
+	u32 curr_status = 0;
 
-	err = ufshcd_get_bkops_status(hba, &status);
+	err = ufshcd_get_bkops_status(hba, &curr_status);
 	if (err) {
 		dev_err(hba->dev, "%s: failed to get BKOPS status %d\n",
 				__func__, err);
 		goto out;
+	} else if (curr_status > BKOPS_STATUS_MAX) {
+		dev_err(hba->dev, "%s: invalid BKOPS status %d\n",
+				__func__, curr_status);
+		err = -EINVAL;
+		goto out;
 	}
 
-	status = status & 0xF;
-
-	/* handle only if status indicates performance impact or critical */
-	if (status >= BKOPS_STATUS_PERF_IMPACT)
+	if (curr_status >= status)
 		err = ufshcd_enable_auto_bkops(hba);
+	else
+		err = ufshcd_disable_auto_bkops(hba);
 out:
 	return err;
 }
 
+/**
+ * ufshcd_urgent_bkops - handle urgent bkops exception event
+ * @hba: per-adapter instance
+ *
+ * Enable fBackgroundOpsEn flag in the device to permit background
+ * operations.
+ *
+ * If BKOPs is enabled, this function returns 0, 1 if the bkops in not enabled
+ * and negative error value for any other failure.
+ */
+static int ufshcd_urgent_bkops(struct ufs_hba *hba)
+{
+	return ufshcd_bkops_ctrl(hba, BKOPS_STATUS_PERF_IMPACT);
+}
+
 static inline int ufshcd_get_ee_status(struct ufs_hba *hba, u32 *status)
 {
 	return ufshcd_query_attr(hba, UPIU_QUERY_OPCODE_READ_ATTR,
@@ -2722,7 +2922,7 @@ static void ufshcd_exception_event_handler(struct work_struct *work)
 	status &= hba->ee_ctrl_mask;
 	if (status & MASK_EE_URGENT_BKOPS) {
 		err = ufshcd_urgent_bkops(hba);
-		if (err)
+		if (err < 0)
 			dev_err(hba->dev, "%s: failed to handle urgent bkops %d\n",
 					__func__, err);
 	}
@@ -3441,7 +3641,8 @@ static int ufshcd_probe_hba(struct ufs_hba *hba)
 	if (ret)
 		goto out;
 
-	ufshcd_config_max_pwr_mode(hba);
+	/* UniPro link is active now */
+	ufshcd_set_link_active(hba);
 
 	ret = ufshcd_verify_dev_init(hba);
 	if (ret)
@@ -3451,14 +3652,29 @@ static int ufshcd_probe_hba(struct ufs_hba *hba)
 	if (ret)
 		goto out;
 
+	/* UFS device is also active now */
+	ufshcd_set_ufs_dev_active(hba);
 	ufshcd_force_reset_auto_bkops(hba);
 	hba->ufshcd_state = UFSHCD_STATE_OPERATIONAL;
+	hba->wlun_dev_clr_ua = true;
+
+	ufshcd_config_max_pwr_mode(hba);
+
+	/*
+	 * If we are in error handling context or in power management callbacks
+	 * context, no need to scan the host
+	 */
+	if (!ufshcd_eh_in_progress(hba) && !hba->pm_op_in_progress) {
+		bool flag;
+
+		/* clear any previous UFS device information */
+		memset(&hba->dev_info, 0, sizeof(hba->dev_info));
+		if (!ufshcd_query_flag(hba, UPIU_QUERY_OPCODE_READ_FLAG,
+				       QUERY_FLAG_IDN_PWR_ON_WPE, &flag))
+			hba->dev_info.f_power_on_wp_en = flag;
 
-	/* If we are in error handling context no need to scan the host */
-	if (!ufshcd_eh_in_progress(hba)) {
 		if (!hba->is_init_prefetch)
 			ufshcd_init_icc_levels(hba);
-
 		scsi_scan_host(hba->host);
 		pm_runtime_put_sync(hba->dev);
 	}
@@ -3471,8 +3687,10 @@ out:
 	 * If we failed to initialize the device or the device is not
 	 * present, turn off the power/clocks etc.
 	 */
-	if (ret && !ufshcd_eh_in_progress(hba))
+	if (ret && !ufshcd_eh_in_progress(hba) && !hba->pm_op_in_progress) {
+		pm_runtime_put_sync(hba->dev);
 		ufshcd_hba_exit(hba);
+	}
 
 	return ret;
 }
@@ -3507,6 +3725,42 @@ static struct scsi_host_template ufshcd_driver_template = {
 	.can_queue		= UFSHCD_CAN_QUEUE,
 };
 
+static int ufshcd_config_vreg_load(struct device *dev, struct ufs_vreg *vreg,
+				   int ua)
+{
+	int ret = 0;
+	struct regulator *reg = vreg->reg;
+	const char *name = vreg->name;
+
+	BUG_ON(!vreg);
+
+	ret = regulator_set_optimum_mode(reg, ua);
+	if (ret >= 0) {
+		/*
+		 * regulator_set_optimum_mode() returns new regulator
+		 * mode upon success.
+		 */
+		ret = 0;
+	} else {
+		dev_err(dev, "%s: %s set optimum mode(ua=%d) failed, err=%d\n",
+				__func__, name, ua, ret);
+	}
+
+	return ret;
+}
+
+static inline int ufshcd_config_vreg_lpm(struct ufs_hba *hba,
+					 struct ufs_vreg *vreg)
+{
+	return ufshcd_config_vreg_load(hba->dev, vreg, UFS_VREG_LPM_LOAD_UA);
+}
+
+static inline int ufshcd_config_vreg_hpm(struct ufs_hba *hba,
+					 struct ufs_vreg *vreg)
+{
+	return ufshcd_config_vreg_load(hba->dev, vreg, vreg->max_uA);
+}
+
 static int ufshcd_config_vreg(struct device *dev,
 		struct ufs_vreg *vreg, bool on)
 {
@@ -3527,18 +3781,9 @@ static int ufshcd_config_vreg(struct device *dev,
 		}
 
 		uA_load = on ? vreg->max_uA : 0;
-		ret = regulator_set_optimum_mode(reg, uA_load);
-		if (ret >= 0) {
-			/*
-			 * regulator_set_optimum_mode() returns new regulator
-			 * mode upon success.
-			 */
-			ret = 0;
-		} else {
-			dev_err(dev, "%s: %s set optimum mode(uA_load=%d) failed, err=%d\n",
-					__func__, name, uA_load, ret);
+		ret = ufshcd_config_vreg_load(dev, vreg, uA_load);
+		if (ret)
 			goto out;
-		}
 	}
 out:
 	return ret;
@@ -3654,7 +3899,8 @@ out:
 	return ret;
 }
 
-static int ufshcd_setup_clocks(struct ufs_hba *hba, bool on)
+static int __ufshcd_setup_clocks(struct ufs_hba *hba, bool on,
+				 bool skip_ref_clk)
 {
 	int ret = 0;
 	struct ufs_clk_info *clki;
@@ -3665,6 +3911,9 @@ static int ufshcd_setup_clocks(struct ufs_hba *hba, bool on)
 
 	list_for_each_entry(clki, head, list) {
 		if (!IS_ERR_OR_NULL(clki->clk)) {
+			if (skip_ref_clk && !strcmp(clki->name, "ref_clk"))
+				continue;
+
 			if (on && !clki->enabled) {
 				ret = clk_prepare_enable(clki->clk);
 				if (ret) {
@@ -3690,6 +3939,11 @@ out:
 	return ret;
 }
 
+static int ufshcd_setup_clocks(struct ufs_hba *hba, bool on)
+{
+	return  __ufshcd_setup_clocks(hba, on, false);
+}
+
 static int ufshcd_init_clocks(struct ufs_hba *hba)
 {
 	int ret = 0;
@@ -3828,68 +4082,514 @@ static void ufshcd_hba_exit(struct ufs_hba *hba)
 	}
 }
 
+static int
+ufshcd_send_request_sense(struct ufs_hba *hba, struct scsi_device *sdp)
+{
+	unsigned char cmd[6] = {REQUEST_SENSE,
+				0,
+				0,
+				0,
+				SCSI_SENSE_BUFFERSIZE,
+				0};
+	char *buffer;
+	int ret;
+
+	buffer = kzalloc(SCSI_SENSE_BUFFERSIZE, GFP_KERNEL);
+	if (!buffer) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	ret = scsi_execute_req_flags(sdp, cmd, DMA_FROM_DEVICE, buffer,
+				SCSI_SENSE_BUFFERSIZE, NULL,
+				msecs_to_jiffies(1000), 3, NULL, REQ_PM);
+	if (ret)
+		pr_err("%s: failed with err %d\n", __func__, ret);
+
+	kfree(buffer);
+out:
+	return ret;
+}
+
 /**
- * ufshcd_suspend - suspend power management function
+ * ufshcd_set_dev_pwr_mode - sends START STOP UNIT command to set device
+ *			     power mode
  * @hba: per adapter instance
- * @state: power state
+ * @pwr_mode: device power mode to set
  *
- * Returns -ENOSYS
+ * Returns 0 if requested power mode is set successfully
+ * Returns non-zero if failed to set the requested power mode
  */
-int ufshcd_suspend(struct ufs_hba *hba, pm_message_t state)
+static int ufshcd_set_dev_pwr_mode(struct ufs_hba *hba,
+				     enum ufs_dev_pwr_mode pwr_mode)
 {
+	unsigned char cmd[6] = { START_STOP };
+	struct scsi_sense_hdr sshdr;
+	struct scsi_device *sdp = hba->sdev_ufs_device;
+	int ret;
+
+	if (!sdp || !scsi_device_online(sdp))
+		return -ENODEV;
+
+	/*
+	 * If scsi commands fail, the scsi mid-layer schedules scsi error-
+	 * handling, which would wait for host to be resumed. Since we know
+	 * we are functional while we are here, skip host resume in error
+	 * handling context.
+	 */
+	hba->host->eh_noresume = 1;
+	if (hba->wlun_dev_clr_ua) {
+		ret = ufshcd_send_request_sense(hba, sdp);
+		if (ret)
+			goto out;
+		/* Unit attention condition is cleared now */
+		hba->wlun_dev_clr_ua = false;
+	}
+
+	cmd[4] = pwr_mode << 4;
+
 	/*
-	 * TODO:
-	 * 1. Block SCSI requests from SCSI midlayer
-	 * 2. Change the internal driver state to non operational
-	 * 3. Set UTRLRSR and UTMRLRSR bits to zero
-	 * 4. Wait until outstanding commands are completed
-	 * 5. Set HCE to zero to send the UFS host controller to reset state
+	 * Current function would be generally called from the power management
+	 * callbacks hence set the REQ_PM flag so that it doesn't resume the
+	 * already suspended childs.
 	 */
+	ret = scsi_execute_req_flags(sdp, cmd, DMA_NONE, NULL, 0, &sshdr,
+				     START_STOP_TIMEOUT, 0, NULL, REQ_PM);
+	if (ret) {
+		sdev_printk(KERN_WARNING, sdp,
+			  "START_STOP failed for power mode: %d\n", pwr_mode);
+		scsi_show_result(ret);
+		if (driver_byte(ret) & DRIVER_SENSE) {
+			scsi_show_sense_hdr(&sshdr);
+			scsi_show_extd_sense(sshdr.asc, sshdr.ascq);
+		}
+	}
 
-	return -ENOSYS;
+	if (!ret)
+		hba->curr_dev_pwr_mode = pwr_mode;
+out:
+	hba->host->eh_noresume = 0;
+	return ret;
+}
+
+static int ufshcd_link_state_transition(struct ufs_hba *hba,
+					enum uic_link_state req_link_state,
+					int check_for_bkops)
+{
+	int ret = 0;
+
+	if (req_link_state == hba->uic_link_state)
+		return 0;
+
+	if (req_link_state == UIC_LINK_HIBERN8_STATE) {
+		ret = ufshcd_uic_hibern8_enter(hba);
+		if (!ret)
+			ufshcd_set_link_hibern8(hba);
+		else
+			goto out;
+	}
+	/*
+	 * If autobkops is enabled, link can't be turned off because
+	 * turning off the link would also turn off the device.
+	 */
+	else if ((req_link_state == UIC_LINK_OFF_STATE) &&
+		   (!check_for_bkops || (check_for_bkops &&
+		    !hba->auto_bkops_enabled))) {
+		/*
+		 * Change controller state to "reset state" which
+		 * should also put the link in off/reset state
+		 */
+		ufshcd_hba_stop(hba);
+		/*
+		 * TODO: Check if we need any delay to make sure that
+		 * controller is reset
+		 */
+		ufshcd_set_link_off(hba);
+	}
+
+out:
+	return ret;
+}
+
+static void ufshcd_vreg_set_lpm(struct ufs_hba *hba)
+{
+	/*
+	 * If UFS device is either in UFS_Sleep turn off VCC rail to save some
+	 * power.
+	 *
+	 * If UFS device and link is in OFF state, all power supplies (VCC,
+	 * VCCQ, VCCQ2) can be turned off if power on write protect is not
+	 * required. If UFS link is inactive (Hibern8 or OFF state) and device
+	 * is in sleep state, put VCCQ & VCCQ2 rails in LPM mode.
+	 *
+	 * Ignore the error returned by ufshcd_toggle_vreg() as device is anyway
+	 * in low power state which would save some power.
+	 */
+	if (ufshcd_is_ufs_dev_poweroff(hba) && ufshcd_is_link_off(hba) &&
+	    !hba->dev_info.is_lu_power_on_wp) {
+		ufshcd_setup_vreg(hba, false);
+	} else if (!ufshcd_is_ufs_dev_active(hba)) {
+		ufshcd_toggle_vreg(hba->dev, hba->vreg_info.vcc, false);
+		if (!ufshcd_is_link_active(hba)) {
+			ufshcd_config_vreg_lpm(hba, hba->vreg_info.vccq);
+			ufshcd_config_vreg_lpm(hba, hba->vreg_info.vccq2);
+		}
+	}
+}
+
+static int ufshcd_vreg_set_hpm(struct ufs_hba *hba)
+{
+	int ret = 0;
+
+	if (ufshcd_is_ufs_dev_poweroff(hba) && ufshcd_is_link_off(hba) &&
+	    !hba->dev_info.is_lu_power_on_wp) {
+		ret = ufshcd_setup_vreg(hba, true);
+	} else if (!ufshcd_is_ufs_dev_active(hba)) {
+		ret = ufshcd_toggle_vreg(hba->dev, hba->vreg_info.vcc, true);
+		if (!ret && !ufshcd_is_link_active(hba)) {
+			ret = ufshcd_config_vreg_hpm(hba, hba->vreg_info.vccq);
+			if (ret)
+				goto vcc_disable;
+			ret = ufshcd_config_vreg_hpm(hba, hba->vreg_info.vccq2);
+			if (ret)
+				goto vccq_lpm;
+		}
+	}
+	goto out;
+
+vccq_lpm:
+	ufshcd_config_vreg_lpm(hba, hba->vreg_info.vccq);
+vcc_disable:
+	ufshcd_toggle_vreg(hba->dev, hba->vreg_info.vcc, false);
+out:
+	return ret;
 }
-EXPORT_SYMBOL_GPL(ufshcd_suspend);
 
 /**
- * ufshcd_resume - resume power management function
+ * ufshcd_suspend - helper function for suspend operations
  * @hba: per adapter instance
+ * @pm_op: desired low power operation type
  *
- * Returns -ENOSYS
+ * This function will try to put the UFS device and link into low power
+ * mode based on the "rpm_lvl" (Runtime PM level) or "spm_lvl"
+ * (System PM level).
+ *
+ * If this function is called during shutdown, it will make sure that
+ * both UFS device and UFS link is powered off.
+ *
+ * NOTE: UFS device & link must be active before we enter in this function.
+ *
+ * Returns 0 for success and non-zero for failure
  */
-int ufshcd_resume(struct ufs_hba *hba)
+static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 {
+	int ret = 0;
+	enum ufs_pm_level pm_lvl;
+	enum ufs_dev_pwr_mode req_dev_pwr_mode;
+	enum uic_link_state req_link_state;
+
+	hba->pm_op_in_progress = 1;
+	if (!ufshcd_is_shutdown_pm(pm_op)) {
+		pm_lvl = ufshcd_is_runtime_pm(pm_op) ?
+			 hba->rpm_lvl : hba->spm_lvl;
+		req_dev_pwr_mode = ufs_get_pm_lvl_to_dev_pwr_mode(pm_lvl);
+		req_link_state = ufs_get_pm_lvl_to_link_pwr_state(pm_lvl);
+	} else {
+		req_dev_pwr_mode = UFS_POWERDOWN_PWR_MODE;
+		req_link_state = UIC_LINK_OFF_STATE;
+	}
+
+	/*
+	 * If we can't transition into any of the low power modes
+	 * just gate the clocks.
+	 */
+	if (req_dev_pwr_mode == UFS_ACTIVE_PWR_MODE &&
+			req_link_state == UIC_LINK_ACTIVE_STATE) {
+		goto disable_clks;
+	}
+
+	if ((req_dev_pwr_mode == hba->curr_dev_pwr_mode) &&
+	    (req_link_state == hba->uic_link_state))
+		goto out;
+
+	/* UFS device & link must be active before we enter in this function */
+	if (!ufshcd_is_ufs_dev_active(hba) || !ufshcd_is_link_active(hba)) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	if (ufshcd_is_runtime_pm(pm_op)) {
+		/*
+		 * The device is idle with no requests in the queue,
+		 * allow background operations if needed.
+		 */
+		ret = ufshcd_bkops_ctrl(hba, BKOPS_STATUS_NON_CRITICAL);
+		if (ret)
+			goto out;
+	}
+
+	if ((req_dev_pwr_mode != hba->curr_dev_pwr_mode) &&
+	     ((ufshcd_is_runtime_pm(pm_op) && !hba->auto_bkops_enabled) ||
+	       !ufshcd_is_runtime_pm(pm_op))) {
+		/* ensure that bkops is disabled */
+		ufshcd_disable_auto_bkops(hba);
+		ret = ufshcd_set_dev_pwr_mode(hba, req_dev_pwr_mode);
+		if (ret)
+			goto out;
+	}
+
+	ret = ufshcd_link_state_transition(hba, req_link_state, 1);
+	if (ret)
+		goto set_dev_active;
+
+	ufshcd_vreg_set_lpm(hba);
+
+disable_clks:
+	/*
+	 * Call vendor specific suspend callback. As these callbacks may access
+	 * vendor specific host controller register space call them before the
+	 * host clocks are ON.
+	 */
+	if (hba->vops && hba->vops->suspend) {
+		ret = hba->vops->suspend(hba, pm_op);
+		if (ret)
+			goto set_link_active;
+	}
+
+	if (hba->vops && hba->vops->setup_clocks) {
+		ret = hba->vops->setup_clocks(hba, false);
+		if (ret)
+			goto vops_resume;
+	}
+
+	if (!ufshcd_is_link_active(hba))
+		ufshcd_setup_clocks(hba, false);
+	else
+		/* If link is active, device ref_clk can't be switched off */
+		__ufshcd_setup_clocks(hba, false, true);
+
 	/*
-	 * TODO:
-	 * 1. Set HCE to 1, to start the UFS host controller
-	 * initialization process
-	 * 2. Set UTRLRSR and UTMRLRSR bits to 1
-	 * 3. Change the internal driver state to operational
-	 * 4. Unblock SCSI requests from SCSI midlayer
+	 * Disable the host irq as host controller as there won't be any
+	 * host controller trasanction expected till resume.
 	 */
+	ufshcd_disable_irq(hba);
+	goto out;
 
-	return -ENOSYS;
+vops_resume:
+	if (hba->vops && hba->vops->resume)
+		hba->vops->resume(hba, pm_op);
+set_link_active:
+	ufshcd_vreg_set_hpm(hba);
+	if (ufshcd_is_link_hibern8(hba) && !ufshcd_uic_hibern8_exit(hba))
+		ufshcd_set_link_active(hba);
+	else if (ufshcd_is_link_off(hba))
+		ufshcd_host_reset_and_restore(hba);
+set_dev_active:
+	if (!ufshcd_set_dev_pwr_mode(hba, UFS_ACTIVE_PWR_MODE))
+		ufshcd_disable_auto_bkops(hba);
+out:
+	hba->pm_op_in_progress = 0;
+	return ret;
 }
-EXPORT_SYMBOL_GPL(ufshcd_resume);
 
-int ufshcd_runtime_suspend(struct ufs_hba *hba)
+/**
+ * ufshcd_resume - helper function for resume operations
+ * @hba: per adapter instance
+ * @pm_op: runtime PM or system PM
+ *
+ * This function basically brings the UFS device, UniPro link and controller
+ * to active state.
+ *
+ * Returns 0 for success and non-zero for failure
+ */
+static int ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 {
-	if (!hba)
-		return 0;
+	int ret;
+	enum uic_link_state old_link_state;
+
+	hba->pm_op_in_progress = 1;
+	old_link_state = hba->uic_link_state;
+	/* Make sure clocks are enabled before accessing controller */
+	ret = ufshcd_setup_clocks(hba, true);
+	if (ret)
+		goto out;
+
+	if (hba->vops && hba->vops->setup_clocks) {
+		ret = hba->vops->setup_clocks(hba, true);
+		if (ret)
+			goto disable_clks;
+	}
+
+	/* enable the host irq as host controller would be active soon */
+	ufshcd_enable_irq(hba);
+
+	ret = ufshcd_vreg_set_hpm(hba);
+	if (ret)
+		goto disable_irq_and_vops_clks;
 
 	/*
-	 * The device is idle with no requests in the queue,
-	 * allow background operations.
+	 * Call vendor specific resume callback. As these callbacks may access
+	 * vendor specific host controller register space call them when the
+	 * host clocks are ON.
 	 */
-	return ufshcd_enable_auto_bkops(hba);
+	if (hba->vops && hba->vops->resume) {
+		ret = hba->vops->resume(hba, pm_op);
+		if (ret)
+			goto disable_vreg;
+	}
+
+	if (ufshcd_is_link_hibern8(hba)) {
+		ret = ufshcd_uic_hibern8_exit(hba);
+		if (!ret)
+			ufshcd_set_link_active(hba);
+		else
+			goto vendor_suspend;
+	} else if (ufshcd_is_link_off(hba)) {
+		ret = ufshcd_host_reset_and_restore(hba);
+		/*
+		 * ufshcd_host_reset_and_restore() should have already
+		 * set the link state as active
+		 */
+		if (ret || !ufshcd_is_link_active(hba))
+			goto vendor_suspend;
+	}
+
+	if (!ufshcd_is_ufs_dev_active(hba)) {
+		ret = ufshcd_set_dev_pwr_mode(hba, UFS_ACTIVE_PWR_MODE);
+		if (ret)
+			goto set_old_link_state;
+	}
+
+	ufshcd_disable_auto_bkops(hba);
+	goto out;
+
+set_old_link_state:
+	ufshcd_link_state_transition(hba, old_link_state, 0);
+vendor_suspend:
+	if (hba->vops && hba->vops->suspend)
+		hba->vops->suspend(hba, pm_op);
+disable_vreg:
+	ufshcd_vreg_set_lpm(hba);
+disable_irq_and_vops_clks:
+	ufshcd_disable_irq(hba);
+	if (hba->vops && hba->vops->setup_clocks)
+		ret = hba->vops->setup_clocks(hba, false);
+disable_clks:
+	ufshcd_setup_clocks(hba, false);
+out:
+	hba->pm_op_in_progress = 0;
+	return ret;
+}
+
+/**
+ * ufshcd_system_suspend - system suspend routine
+ * @hba: per adapter instance
+ * @pm_op: runtime PM or system PM
+ *
+ * Check the description of ufshcd_suspend() function for more details.
+ *
+ * Returns 0 for success and non-zero for failure
+ */
+int ufshcd_system_suspend(struct ufs_hba *hba)
+{
+	int ret = 0;
+
+	if (!hba || !hba->is_powered)
+		goto out;
+
+	if (pm_runtime_suspended(hba->dev)) {
+		if (hba->rpm_lvl == hba->spm_lvl)
+			/*
+			 * There is possibility that device may still be in
+			 * active state during the runtime suspend.
+			 */
+			if ((ufs_get_pm_lvl_to_dev_pwr_mode(hba->spm_lvl) ==
+			    hba->curr_dev_pwr_mode) && !hba->auto_bkops_enabled)
+				goto out;
+
+		/*
+		 * UFS device and/or UFS link low power states during runtime
+		 * suspend seems to be different than what is expected during
+		 * system suspend. Hence runtime resume the devic & link and
+		 * let the system suspend low power states to take effect.
+		 * TODO: If resume takes longer time, we might have optimize
+		 * it in future by not resuming everything if possible.
+		 */
+		ret = ufshcd_runtime_resume(hba);
+		if (ret)
+			goto out;
+	}
+
+	ret = ufshcd_suspend(hba, UFS_SYSTEM_PM);
+out:
+	return ret;
+}
+EXPORT_SYMBOL(ufshcd_system_suspend);
+
+/**
+ * ufshcd_system_resume - system resume routine
+ * @hba: per adapter instance
+ *
+ * Returns 0 for success and non-zero for failure
+ */
+
+int ufshcd_system_resume(struct ufs_hba *hba)
+{
+	if (!hba || !hba->is_powered || pm_runtime_suspended(hba->dev))
+		/*
+		 * Let the runtime resume take care of resuming
+		 * if runtime suspended.
+		 */
+		return 0;
+	else
+		return ufshcd_resume(hba, UFS_SYSTEM_PM);
+}
+EXPORT_SYMBOL(ufshcd_system_resume);
+
+/**
+ * ufshcd_runtime_suspend - runtime suspend routine
+ * @hba: per adapter instance
+ *
+ * Check the description of ufshcd_suspend() function for more details.
+ *
+ * Returns 0 for success and non-zero for failure
+ */
+int ufshcd_runtime_suspend(struct ufs_hba *hba)
+{
+	if (!hba || !hba->is_powered)
+		return 0;
+	else
+		return ufshcd_suspend(hba, UFS_RUNTIME_PM);
 }
 EXPORT_SYMBOL(ufshcd_runtime_suspend);
 
+/**
+ * ufshcd_runtime_resume - runtime resume routine
+ * @hba: per adapter instance
+ *
+ * This function basically brings the UFS device, UniPro link and controller
+ * to active state. Following operations are done in this function:
+ *
+ * 1. Turn on all the controller related clocks
+ * 2. Bring the UniPro link out of Hibernate state
+ * 3. If UFS device is in sleep state, turn ON VCC rail and bring the UFS device
+ *    to active state.
+ * 4. If auto-bkops is enabled on the device, disable it.
+ *
+ * So following would be the possible power state after this function return
+ * successfully:
+ *	S1: UFS device in Active state with VCC rail ON
+ *	    UniPro link in Active state
+ *	    All the UFS/UniPro controller clocks are ON
+ *
+ * Returns 0 for success and non-zero for failure
+ */
 int ufshcd_runtime_resume(struct ufs_hba *hba)
 {
-	if (!hba)
+	if (!hba || !hba->is_powered)
 		return 0;
-
-	return ufshcd_disable_auto_bkops(hba);
+	else
+		return ufshcd_resume(hba, UFS_RUNTIME_PM);
 }
 EXPORT_SYMBOL(ufshcd_runtime_resume);
 
@@ -3900,6 +4600,36 @@ int ufshcd_runtime_idle(struct ufs_hba *hba)
 EXPORT_SYMBOL(ufshcd_runtime_idle);
 
 /**
+ * ufshcd_shutdown - shutdown routine
+ * @hba: per adapter instance
+ *
+ * This function would power off both UFS device and UFS link.
+ *
+ * Returns 0 always to allow force shutdown even in case of errors.
+ */
+int ufshcd_shutdown(struct ufs_hba *hba)
+{
+	int ret = 0;
+
+	if (ufshcd_is_ufs_dev_poweroff(hba) && ufshcd_is_link_off(hba))
+		goto out;
+
+	if (pm_runtime_suspended(hba->dev)) {
+		ret = ufshcd_runtime_resume(hba);
+		if (ret)
+			goto out;
+	}
+
+	ret = ufshcd_suspend(hba, UFS_SHUTDOWN_PM);
+out:
+	if (ret)
+		dev_err(hba->dev, "%s failed, err %d\n", __func__, ret);
+	/* allow force shutdown even in case of errors */
+	return 0;
+}
+EXPORT_SYMBOL(ufshcd_shutdown);
+
+/**
  * ufshcd_remove - de-allocate SCSI host and host memory space
  *		data structure memory
  * @hba - per adapter instance
@@ -4052,6 +4782,8 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq)
 	if (err) {
 		dev_err(hba->dev, "request irq failed\n");
 		goto out_disable;
+	} else {
+		hba->is_irq_enabled = true;
 	}
 
 	/* Enable SCSI tag mapping */
@@ -4077,6 +4809,12 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq)
 	/* Hold auto suspend until async scan completes */
 	pm_runtime_get_sync(dev);
 
+	/*
+	 * The device-initialize-sequence hasn't been invoked yet.
+	 * Set the device to power-off state
+	 */
+	ufshcd_set_ufs_dev_poweroff(hba);
+
 	async_schedule(ufshcd_async_scan, hba);
 
 	return 0;
@@ -4084,6 +4822,7 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq)
 out_remove_scsi_host:
 	scsi_remove_host(hba->host);
 out_disable:
+	hba->is_irq_enabled = false;
 	scsi_host_put(host);
 	ufshcd_hba_exit(hba);
 out_error:
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index 9b5f77f..1ee429d 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -96,6 +96,54 @@ struct uic_command {
 	struct completion done;
 };
 
+/* Used to differentiate the power management options */
+enum ufs_pm_op {
+	UFS_RUNTIME_PM,
+	UFS_SYSTEM_PM,
+	UFS_SHUTDOWN_PM,
+};
+
+#define ufshcd_is_runtime_pm(op) ((op) == UFS_RUNTIME_PM)
+#define ufshcd_is_system_pm(op) ((op) == UFS_SYSTEM_PM)
+#define ufshcd_is_shutdown_pm(op) ((op) == UFS_SHUTDOWN_PM)
+
+/* Host <-> Device UniPro Link state */
+enum uic_link_state {
+	UIC_LINK_OFF_STATE	= 0, /* Link powered down or disabled */
+	UIC_LINK_ACTIVE_STATE	= 1, /* Link is in Fast/Slow/Sleep state */
+	UIC_LINK_HIBERN8_STATE	= 2, /* Link is in Hibernate state */
+};
+
+#define ufshcd_is_link_off(hba) ((hba)->uic_link_state == UIC_LINK_OFF_STATE)
+#define ufshcd_is_link_active(hba) ((hba)->uic_link_state == \
+				    UIC_LINK_ACTIVE_STATE)
+#define ufshcd_is_link_hibern8(hba) ((hba)->uic_link_state == \
+				    UIC_LINK_HIBERN8_STATE)
+#define ufshcd_set_link_off(hba) ((hba)->uic_link_state = UIC_LINK_OFF_STATE)
+#define ufshcd_set_link_active(hba) ((hba)->uic_link_state = \
+				    UIC_LINK_ACTIVE_STATE)
+#define ufshcd_set_link_hibern8(hba) ((hba)->uic_link_state = \
+				    UIC_LINK_HIBERN8_STATE)
+
+/*
+ * UFS Power management levels.
+ * Each level is in increasing order of power savings.
+ */
+enum ufs_pm_level {
+	UFS_PM_LVL_0, /* UFS_ACTIVE_PWR_MODE, UIC_LINK_ACTIVE_STATE */
+	UFS_PM_LVL_1, /* UFS_ACTIVE_PWR_MODE, UIC_LINK_HIBERN8_STATE */
+	UFS_PM_LVL_2, /* UFS_SLEEP_PWR_MODE, UIC_LINK_ACTIVE_STATE */
+	UFS_PM_LVL_3, /* UFS_SLEEP_PWR_MODE, UIC_LINK_HIBERN8_STATE */
+	UFS_PM_LVL_4, /* UFS_POWERDOWN_PWR_MODE, UIC_LINK_HIBERN8_STATE */
+	UFS_PM_LVL_5, /* UFS_POWERDOWN_PWR_MODE, UIC_LINK_OFF_STATE */
+	UFS_PM_LVL_MAX
+};
+
+struct ufs_pm_lvl_states {
+	enum ufs_dev_pwr_mode dev_state;
+	enum uic_link_state link_state;
+};
+
 /**
  * struct ufshcd_lrb - local reference block
  * @utr_descriptor_ptr: UTRD address of the command
@@ -184,6 +232,8 @@ struct ufs_clk_info {
  *                     variant specific Uni-Pro initialization.
  * @link_startup_notify: called before and after Link startup is carried out
  *                       to allow variant specific Uni-Pro initialization.
+ * @suspend: called during host controller PM callback
+ * @resume: called during host controller PM callback
  */
 struct ufs_hba_variant_ops {
 	const char *name;
@@ -193,6 +243,8 @@ struct ufs_hba_variant_ops {
 	int     (*setup_regulators)(struct ufs_hba *, bool);
 	int     (*hce_enable_notify)(struct ufs_hba *, bool);
 	int     (*link_startup_notify)(struct ufs_hba *, bool);
+	int     (*suspend)(struct ufs_hba *, enum ufs_pm_op);
+	int     (*resume)(struct ufs_hba *, enum ufs_pm_op);
 };
 
 /**
@@ -271,6 +323,13 @@ struct ufs_hba {
 	 * "UFS device" W-LU.
 	 */
 	struct scsi_device *sdev_ufs_device;
+	enum ufs_dev_pwr_mode curr_dev_pwr_mode;
+	enum uic_link_state uic_link_state;
+	/* Desired UFS power management level during runtime PM */
+	enum ufs_pm_level rpm_lvl;
+	/* Desired UFS power management level during system PM */
+	enum ufs_pm_level spm_lvl;
+	int pm_op_in_progress;
 
 	struct ufshcd_lrb *lrb;
 	unsigned long lrb_in_use;
@@ -285,16 +344,17 @@ struct ufs_hba {
 	struct ufs_hba_variant_ops *vops;
 	void *priv;
 	unsigned int irq;
+	bool is_irq_enabled;
 
-	struct uic_command *active_uic_cmd;
-	struct mutex uic_cmd_mutex;
 
 	wait_queue_head_t tm_wq;
 	wait_queue_head_t tm_tag_wq;
 	unsigned long tm_condition;
 	unsigned long tm_slots_in_use;
 
-	struct completion *pwr_done;
+	struct uic_command *active_uic_cmd;
+	struct mutex uic_cmd_mutex;
+	struct completion *uic_async_done;
 
 	u32 ufshcd_state;
 	u32 eh_flags;
@@ -317,9 +377,13 @@ struct ufs_hba {
 	/* Device management request data */
 	struct ufs_dev_cmd dev_cmd;
 
+	/* Keeps information of the UFS device connected to this host */
+	struct ufs_dev_info dev_info;
 	bool auto_bkops_enabled;
 	struct ufs_vreg_info vreg_info;
 	struct list_head clk_list_head;
+
+	bool wlun_dev_clr_ua;
 };
 
 #define ufshcd_writel(hba, val, reg)	\
@@ -346,11 +410,12 @@ static inline void check_upiu_size(void)
 		GENERAL_UPIU_REQUEST_SIZE + QUERY_DESC_MAX_SIZE);
 }
 
-extern int ufshcd_suspend(struct ufs_hba *hba, pm_message_t state);
-extern int ufshcd_resume(struct ufs_hba *hba);
 extern int ufshcd_runtime_suspend(struct ufs_hba *hba);
 extern int ufshcd_runtime_resume(struct ufs_hba *hba);
 extern int ufshcd_runtime_idle(struct ufs_hba *hba);
+extern int ufshcd_system_suspend(struct ufs_hba *hba);
+extern int ufshcd_system_resume(struct ufs_hba *hba);
+extern int ufshcd_shutdown(struct ufs_hba *hba);
 extern int ufshcd_dme_set_attr(struct ufs_hba *hba, u32 attr_sel,
 			       u8 attr_set, u32 mib_val, u8 peer);
 extern int ufshcd_dme_get_attr(struct ufs_hba *hba, u32 attr_sel,
diff --git a/drivers/scsi/ufs/ufshci.h b/drivers/scsi/ufs/ufshci.h
index e1b844b..d572119 100644
--- a/drivers/scsi/ufs/ufshci.h
+++ b/drivers/scsi/ufs/ufshci.h
@@ -124,8 +124,11 @@ enum {
 #define CONTROLLER_FATAL_ERROR			UFS_BIT(16)
 #define SYSTEM_BUS_FATAL_ERROR			UFS_BIT(17)
 
-#define UFSHCD_UIC_MASK		(UIC_COMMAND_COMPL |\
-				 UIC_POWER_MODE)
+#define UFSHCD_UIC_PWR_MASK	(UIC_HIBERNATE_ENTER |\
+				UIC_HIBERNATE_EXIT |\
+				UIC_POWER_MODE)
+
+#define UFSHCD_UIC_MASK		(UIC_COMMAND_COMPL | UFSHCD_UIC_PWR_MASK)
 
 #define UFSHCD_ERROR_MASK	(UIC_ERROR |\
 				DEVICE_FATAL_ERROR |\
@@ -210,7 +213,7 @@ enum {
 #define UIC_GET_ATTR_ID(v)		(((v) >> 16) & 0xFFFF)
 
 /* UIC Commands */
-enum {
+enum uic_cmd_dme {
 	UIC_CMD_DME_GET			= 0x01,
 	UIC_CMD_DME_SET			= 0x02,
 	UIC_CMD_DME_PEER_GET		= 0x03,
-- 
1.8.5.2
-- 
QUALCOMM ISRAEL, on behalf of Qualcomm Innovation Center, Inc. is a member
of Code Aurora Forum, hosted by The Linux Foundation

RE: [PATCH/RFC V2 10/16] scsi: ufs: add UFS power management support

[Dong, Chuanxiao]

> -----Original Message-----
> From: linux-scsi-owner@vger.kernel.org
> [mailto:linux-scsi-owner@vger.kernel.org] On Behalf Of Dolev Raviv
> Sent: Thursday, August 14, 2014 9:31 PM
> To: James.Bottomley@HansenPartnership.com; hch@infradead.org
> Cc: linux-scsi@vger.kernel.org; linux-scsi-owner@vger.kernel.org;
> linux-arm-msm@vger.kernel.org; santoshsy@gmail.com; Subhash Jadavani;
> Dolev Raviv; Sujit Reddy Thumma
> Subject: [PATCH/RFC V2 10/16] scsi: ufs: add UFS power management support
> 
> From: Subhash Jadavani <subhashj@codeaurora.org>
> 
> This patch adds support for UFS device and UniPro link power management
> during runtime/system PM.
> 
> Main idea is to define multiple UFS low power levels based on UFS device and
> UFS link power states. This would allow any specific platform or pci driver to
> choose the best suited low power level during runtime and system suspend
> based on their power goals.
> 
> bkops handlig:
> To put the UFS device in sleep state when bkops is disabled, first query the
> bkops status from the device and enable bkops on device only if device needs
> time to perform the bkops.
> 
> START_STOP handling:
> Before sending START_STOP_UNIT to the device well-known logical unit
> (w-lun) to make sure that the device w-lun unit attention condition is cleared.
> 
> Write protection:
> UFS device specification allows LUs to be write protected, either permanently
> or power on write protected. If any LU is power on write protected and if the
> card is power cycled (by powering off VCCQ and/or VCC rails), LU's write
> protect status would be lost. So this means those LUs can be written now. To
> ensures that UFS device is power cycled only if the power on protect is not set
> for any of the LUs, check if power on write protect is set and if device is in
> sleep/power-off state & link in inactive state (Hibern8 or OFF state).
> If none of the Logical Units on UFS device is power on write protected then all
> UFS device power rails (VCC, VCCQ & VCCQ2) can be turned off if UFS device is
> in power-off state and UFS link is in OFF state. But current implementation
> would disable all device power rails even if UFS link is not in OFF state.
> 
> Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
> Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
> Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
> 
> diff --git a/drivers/scsi/ufs/ufs.h b/drivers/scsi/ufs/ufs.h index
> bcc3a7f..2a82959 100644
> --- a/drivers/scsi/ufs/ufs.h
> +++ b/drivers/scsi/ufs/ufs.h
> @@ -129,6 +129,7 @@ enum {
>  /* Flag idn for Query Requests*/
>  enum flag_idn {
>  	QUERY_FLAG_IDN_FDEVICEINIT      = 0x01,
> +	QUERY_FLAG_IDN_PWR_ON_WPE	= 0x03,
>  	QUERY_FLAG_IDN_BKOPS_EN         = 0x04,
>  };
> 
> @@ -194,6 +195,18 @@ enum unit_desc_param {
>  	UNIT_DESC_PARAM_LARGE_UNIT_SIZE_M1	= 0x22,
>  };
> 
> +/*
> + * Logical Unit Write Protect
> + * 00h: LU not write protected
> + * 01h: LU write protected when fPowerOnWPEn =1
> + * 02h: LU permanently write protected when fPermanentWPEn =1  */ enum
> +ufs_lu_wp_type {
> +	UFS_LU_NO_WP		= 0x00,
> +	UFS_LU_POWER_ON_WP	= 0x01,
> +	UFS_LU_PERM_WP		= 0x02,
> +};
> +
>  /* bActiveICCLevel parameter current units */  enum {
>  	UFSHCD_NANO_AMP		= 0,
> @@ -226,11 +239,12 @@ enum {
>  };
> 
>  /* Background operation status */
> -enum {
> +enum bkops_status {
>  	BKOPS_STATUS_NO_OP               = 0x0,
>  	BKOPS_STATUS_NON_CRITICAL        = 0x1,
>  	BKOPS_STATUS_PERF_IMPACT         = 0x2,
>  	BKOPS_STATUS_CRITICAL            = 0x3,
> +	BKOPS_STATUS_MAX		 = BKOPS_STATUS_CRITICAL,
>  };
> 
>  /* UTP QUERY Transaction Specific Fields OpCode */ @@ -291,6 +305,14 @@
> enum {
>  	UPIU_TASK_MANAGEMENT_FUNC_FAILED	= 0x05,
>  	UPIU_INCORRECT_LOGICAL_UNIT_NO		= 0x09,
>  };
> +
> +/* UFS device power modes */
> +enum ufs_dev_pwr_mode {
> +	UFS_ACTIVE_PWR_MODE	= 1,
> +	UFS_SLEEP_PWR_MODE	= 2,
> +	UFS_POWERDOWN_PWR_MODE	= 3,
> +};
> +
>  /**
>   * struct utp_upiu_header - UPIU header structure
>   * @dword_0: UPIU header DW-0
> @@ -437,6 +459,12 @@ struct ufs_query_res {
>  #define UFS_VREG_VCCQ2_MIN_UV	   1650000 /* uV */
>  #define UFS_VREG_VCCQ2_MAX_UV	   1950000 /* uV */
> 
> +/*
> + * VCCQ & VCCQ2 current requirement when UFS device is in sleep state
> + * and link is in Hibern8 state.
> + */
> +#define UFS_VREG_LPM_LOAD_UA	1000 /* uA */
> +
>  struct ufs_vreg {
>  	struct regulator *reg;
>  	const char *name;
> @@ -453,4 +481,10 @@ struct ufs_vreg_info {
>  	struct ufs_vreg *vccq2;
>  };
> 
> +struct ufs_dev_info {
> +	bool f_power_on_wp_en;
> +	/* Keeps information if any of the LU is power on write protected */
> +	bool is_lu_power_on_wp;
> +};
> +
>  #endif /* End of Header */
> diff --git a/drivers/scsi/ufs/ufshcd-pci.c b/drivers/scsi/ufs/ufshcd-pci.c index
> 1aac2ef..b8f7774 100644
> --- a/drivers/scsi/ufs/ufshcd-pci.c
> +++ b/drivers/scsi/ufs/ufshcd-pci.c
> @@ -43,34 +43,24 @@
>   * @pdev: pointer to PCI device handle
>   * @state: power state
>   *
> - * Returns -ENOSYS
> + * Returns 0 if successful
> + * Returns non-zero otherwise
>   */
>  static int ufshcd_pci_suspend(struct device *dev)  {
> -	/*
> -	 * TODO:
> -	 * 1. Call ufshcd_suspend
> -	 * 2. Do bus specific power management
> -	 */
> -
> -	return -ENOSYS;
> +	return ufshcd_system_suspend(dev_get_drvdata(dev));
>  }
> 
>  /**
>   * ufshcd_pci_resume - resume power management function
>   * @pdev: pointer to PCI device handle
>   *
> - * Returns -ENOSYS
> + * Returns 0 if successful
> + * Returns non-zero otherwise
>   */
>  static int ufshcd_pci_resume(struct device *dev)  {
> -	/*
> -	 * TODO:
> -	 * 1. Call ufshcd_resume.
> -	 * 2. Do bus specific wake up
> -	 */
> -
> -	return -ENOSYS;
> +	return ufshcd_system_resume(dev_get_drvdata(dev));
>  }
>  #else
>  #define ufshcd_pci_suspend	NULL
> @@ -80,30 +70,15 @@ static int ufshcd_pci_resume(struct device *dev)
> #ifdef CONFIG_PM_RUNTIME  static int ufshcd_pci_runtime_suspend(struct
> device *dev)  {
> -	struct ufs_hba *hba = dev_get_drvdata(dev);
> -
> -	if (!hba)
> -		return 0;
> -
> -	return ufshcd_runtime_suspend(hba);
> +	return ufshcd_runtime_suspend(dev_get_drvdata(dev));
>  }
>  static int ufshcd_pci_runtime_resume(struct device *dev)  {
> -	struct ufs_hba *hba = dev_get_drvdata(dev);
> -
> -	if (!hba)
> -		return 0;
> -
> -	return ufshcd_runtime_resume(hba);
> +	return ufshcd_runtime_resume(dev_get_drvdata(dev));
>  }
>  static int ufshcd_pci_runtime_idle(struct device *dev)  {
> -	struct ufs_hba *hba = dev_get_drvdata(dev);
> -
> -	if (!hba)
> -		return 0;
> -
> -	return ufshcd_runtime_idle(hba);
> +	return ufshcd_runtime_idle(dev_get_drvdata(dev));
>  }
>  #else /* !CONFIG_PM_RUNTIME */
>  #define ufshcd_pci_runtime_suspend	NULL
> @@ -117,7 +92,7 @@ static int ufshcd_pci_runtime_idle(struct device *dev)
>   */
>  static void ufshcd_pci_shutdown(struct pci_dev *pdev)  {
> -	ufshcd_hba_stop((struct ufs_hba *)pci_get_drvdata(pdev));
> +	ufshcd_shutdown((struct ufs_hba *)pci_get_drvdata(pdev));
>  }
> 
>  /**
> diff --git a/drivers/scsi/ufs/ufshcd-pltfrm.c b/drivers/scsi/ufs/ufshcd-pltfrm.c
> index 642d80f..edaccd0 100644
> --- a/drivers/scsi/ufs/ufshcd-pltfrm.c
> +++ b/drivers/scsi/ufs/ufshcd-pltfrm.c
> @@ -216,45 +216,24 @@ out:
>   * ufshcd_pltfrm_suspend - suspend power management function
>   * @dev: pointer to device handle
>   *
> - *
> - * Returns 0
> + * Returns 0 if successful
> + * Returns non-zero otherwise
>   */
>  static int ufshcd_pltfrm_suspend(struct device *dev)  {
> -	struct platform_device *pdev = to_platform_device(dev);
> -	struct ufs_hba *hba =  platform_get_drvdata(pdev);
> -
> -	/*
> -	 * TODO:
> -	 * 1. Call ufshcd_suspend
> -	 * 2. Do bus specific power management
> -	 */
> -
> -	disable_irq(hba->irq);
> -
> -	return 0;
> +	return ufshcd_system_suspend(dev_get_drvdata(dev));
>  }
> 
>  /**
>   * ufshcd_pltfrm_resume - resume power management function
>   * @dev: pointer to device handle
>   *
> - * Returns 0
> + * Returns 0 if successful
> + * Returns non-zero otherwise
>   */
>  static int ufshcd_pltfrm_resume(struct device *dev)  {
> -	struct platform_device *pdev = to_platform_device(dev);
> -	struct ufs_hba *hba =  platform_get_drvdata(pdev);
> -
> -	/*
> -	 * TODO:
> -	 * 1. Call ufshcd_resume.
> -	 * 2. Do bus specific wake up
> -	 */
> -
> -	enable_irq(hba->irq);
> -
> -	return 0;
> +	return ufshcd_system_resume(dev_get_drvdata(dev));
>  }
>  #else
>  #define ufshcd_pltfrm_suspend	NULL
> @@ -264,30 +243,15 @@ static int ufshcd_pltfrm_resume(struct device *dev)
> #ifdef CONFIG_PM_RUNTIME  static int
> ufshcd_pltfrm_runtime_suspend(struct device *dev)  {
> -	struct ufs_hba *hba =  dev_get_drvdata(dev);
> -
> -	if (!hba)
> -		return 0;
> -
> -	return ufshcd_runtime_suspend(hba);
> +	return ufshcd_runtime_suspend(dev_get_drvdata(dev));
>  }
>  static int ufshcd_pltfrm_runtime_resume(struct device *dev)  {
> -	struct ufs_hba *hba =  dev_get_drvdata(dev);
> -
> -	if (!hba)
> -		return 0;
> -
> -	return ufshcd_runtime_resume(hba);
> +	return ufshcd_runtime_resume(dev_get_drvdata(dev));
>  }
>  static int ufshcd_pltfrm_runtime_idle(struct device *dev)  {
> -	struct ufs_hba *hba =  dev_get_drvdata(dev);
> -
> -	if (!hba)
> -		return 0;
> -
> -	return ufshcd_runtime_idle(hba);
> +	return ufshcd_runtime_idle(dev_get_drvdata(dev));
>  }
>  #else /* !CONFIG_PM_RUNTIME */
>  #define ufshcd_pltfrm_runtime_suspend	NULL
> @@ -295,6 +259,11 @@ static int ufshcd_pltfrm_runtime_idle(struct device
> *dev)
>  #define ufshcd_pltfrm_runtime_idle	NULL
>  #endif /* CONFIG_PM_RUNTIME */
> 
> +static void ufshcd_pltfrm_shutdown(struct platform_device *pdev) {
> +	ufshcd_shutdown((struct ufs_hba *)platform_get_drvdata(pdev)); }
> +
>  /**
>   * ufshcd_pltfrm_probe - probe routine of the driver
>   * @pdev: pointer to Platform device handle @@ -395,6 +364,7 @@ static
> const struct dev_pm_ops ufshcd_dev_pm_ops = {  static struct
> platform_driver ufshcd_pltfrm_driver = {
>  	.probe	= ufshcd_pltfrm_probe,
>  	.remove	= ufshcd_pltfrm_remove,
> +	.shutdown = ufshcd_pltfrm_shutdown,
>  	.driver	= {
>  		.name	= "ufshcd",
>  		.owner	= THIS_MODULE,
> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index
> 876d210..fac71c9 100644
> --- a/drivers/scsi/ufs/ufshcd.c
> +++ b/drivers/scsi/ufs/ufshcd.c
> @@ -44,7 +44,6 @@
> 
>  #define UFSHCD_ENABLE_INTRS	(UTP_TRANSFER_REQ_COMPL |\
>  				 UTP_TASK_REQ_COMPL |\
> -				 UIC_POWER_MODE |\
>  				 UFSHCD_ERROR_MASK)
>  /* UIC command timeout, unit: ms */
>  #define UIC_CMD_TIMEOUT	500
> @@ -138,12 +137,63 @@ enum {
>  #define ufshcd_clear_eh_in_progress(h) \
>  	(h->eh_flags &= ~UFSHCD_EH_IN_PROGRESS)
> 
> +#define ufshcd_set_ufs_dev_active(h) \
> +	((h)->curr_dev_pwr_mode = UFS_ACTIVE_PWR_MODE) #define
> +ufshcd_set_ufs_dev_sleep(h) \
> +	((h)->curr_dev_pwr_mode = UFS_SLEEP_PWR_MODE) #define
> +ufshcd_set_ufs_dev_poweroff(h) \
> +	((h)->curr_dev_pwr_mode = UFS_POWERDOWN_PWR_MODE) #define
> +ufshcd_is_ufs_dev_active(h) \
> +	((h)->curr_dev_pwr_mode == UFS_ACTIVE_PWR_MODE) #define
> +ufshcd_is_ufs_dev_sleep(h) \
> +	((h)->curr_dev_pwr_mode == UFS_SLEEP_PWR_MODE) #define
> +ufshcd_is_ufs_dev_poweroff(h) \
> +	((h)->curr_dev_pwr_mode == UFS_POWERDOWN_PWR_MODE)
> +
> +static struct ufs_pm_lvl_states ufs_pm_lvl_states[] = {
> +	{UFS_ACTIVE_PWR_MODE, UIC_LINK_ACTIVE_STATE},
> +	{UFS_ACTIVE_PWR_MODE, UIC_LINK_HIBERN8_STATE},
> +	{UFS_SLEEP_PWR_MODE, UIC_LINK_ACTIVE_STATE},
> +	{UFS_SLEEP_PWR_MODE, UIC_LINK_HIBERN8_STATE},
> +	{UFS_POWERDOWN_PWR_MODE, UIC_LINK_HIBERN8_STATE},
> +	{UFS_POWERDOWN_PWR_MODE, UIC_LINK_OFF_STATE}, };
> +
> +static inline enum ufs_dev_pwr_mode
> +ufs_get_pm_lvl_to_dev_pwr_mode(enum ufs_pm_level lvl) {
> +	return ufs_pm_lvl_states[lvl].dev_state; }
> +
> +static inline enum uic_link_state
> +ufs_get_pm_lvl_to_link_pwr_state(enum ufs_pm_level lvl) {
> +	return ufs_pm_lvl_states[lvl].link_state;
> +}
> +
>  static void ufshcd_tmc_handler(struct ufs_hba *hba);  static void
> ufshcd_async_scan(void *data, async_cookie_t cookie);  static int
> ufshcd_reset_and_restore(struct ufs_hba *hba);  static int
> ufshcd_clear_tm_cmd(struct ufs_hba *hba, int tag);  static void
> ufshcd_hba_exit(struct ufs_hba *hba);  static int ufshcd_probe_hba(struct
> ufs_hba *hba);
> +static int ufshcd_host_reset_and_restore(struct ufs_hba *hba);
> +
> +static inline void ufshcd_enable_irq(struct ufs_hba *hba) {
> +	if (!hba->is_irq_enabled) {
> +		enable_irq(hba->irq);
> +		hba->is_irq_enabled = true;
> +	}
> +}
> +
> +static inline void ufshcd_disable_irq(struct ufs_hba *hba) {
> +	if (hba->is_irq_enabled) {
> +		disable_irq(hba->irq);
> +		hba->is_irq_enabled = false;
> +	}
> +}
> 
>  /*
>   * ufshcd_wait_for_register - wait for register value to change @@ -1778,44
> +1828,48 @@ out:
>  EXPORT_SYMBOL_GPL(ufshcd_dme_get_attr);
> 
>  /**
> - * ufshcd_uic_change_pwr_mode - Perform the UIC power mode chage
> - *				using DME_SET primitives.
> + * ufshcd_uic_pwr_ctrl - executes UIC commands (which affects the link
> + power
> + * state) and waits for it to take effect.
> + *
>   * @hba: per adapter instance
> - * @mode: powr mode value
> + * @cmd: UIC command to execute
> + *
> + * DME operations like DME_SET(PA_PWRMODE), DME_HIBERNATE_ENTER
> &
> + * DME_HIBERNATE_EXIT commands take some time to take its effect on
> + both host
> + * and device UniPro link and hence it's final completion would be
> + indicated by
> + * dedicated status bits in Interrupt Status register (UPMS, UHES,
> + UHXS) in
> + * addition to normal UIC command completion Status (UCCS). This
> + function only
> + * returns after the relevant status bits indicate the completion.
>   *
>   * Returns 0 on success, non-zero value on failure
>   */
> -static int ufshcd_uic_change_pwr_mode(struct ufs_hba *hba, u8 mode)
> +int ufshcd_uic_pwr_ctrl(struct ufs_hba *hba, struct uic_command *cmd)
>  {
> -	struct uic_command uic_cmd = {0};
> -	struct completion pwr_done;
> +	struct completion uic_async_done;
>  	unsigned long flags;
>  	u8 status;
>  	int ret;
> 
> -	uic_cmd.command = UIC_CMD_DME_SET;
> -	uic_cmd.argument1 = UIC_ARG_MIB(PA_PWRMODE);
> -	uic_cmd.argument3 = mode;
> -	init_completion(&pwr_done);
> -
>  	mutex_lock(&hba->uic_cmd_mutex);
> +	init_completion(&uic_async_done);
> 
>  	spin_lock_irqsave(hba->host->host_lock, flags);
> -	hba->pwr_done = &pwr_done;
> +	hba->uic_async_done = &uic_async_done;
>  	spin_unlock_irqrestore(hba->host->host_lock, flags);
> -	ret = __ufshcd_send_uic_cmd(hba, &uic_cmd);
> +
> +	ret = __ufshcd_send_uic_cmd(hba, cmd);
>  	if (ret) {
>  		dev_err(hba->dev,
> -			"pwr mode change with mode 0x%x uic error %d\n",
> -			mode, ret);
> +			"pwr ctrl cmd 0x%x with mode 0x%x uic error %d\n",
> +			cmd->command, cmd->argument3, ret);
>  		goto out;
>  	}
> 
> -	if (!wait_for_completion_timeout(hba->pwr_done,
> +	if (!wait_for_completion_timeout(hba->uic_async_done,
>  					 msecs_to_jiffies(UIC_CMD_TIMEOUT))) {
>  		dev_err(hba->dev,
> -			"pwr mode change with mode 0x%x completion timeout\n",
> -			mode);
> +			"pwr ctrl cmd 0x%x with mode 0x%x completion timeout\n",
> +			cmd->command, cmd->argument3);
>  		ret = -ETIMEDOUT;
>  		goto out;
>  	}
> @@ -1823,19 +1877,62 @@ static int ufshcd_uic_change_pwr_mode(struct
> ufs_hba *hba, u8 mode)
>  	status = ufshcd_get_upmcrs(hba);
>  	if (status != PWR_LOCAL) {
>  		dev_err(hba->dev,
> -			"pwr mode change failed, host umpcrs:0x%x\n",
> -			status);
> +			"pwr ctrl cmd 0x%0x failed, host umpcrs:0x%x\n",
> +			cmd->command, status);
>  		ret = (status != PWR_OK) ? status : -1;
>  	}
>  out:
>  	spin_lock_irqsave(hba->host->host_lock, flags);
> -	hba->pwr_done = NULL;
> +	hba->uic_async_done = NULL;
>  	spin_unlock_irqrestore(hba->host->host_lock, flags);
>  	mutex_unlock(&hba->uic_cmd_mutex);
>  	return ret;
>  }
> 
>  /**
> + * ufshcd_uic_change_pwr_mode - Perform the UIC power mode chage
> + *				using DME_SET primitives.
> + * @hba: per adapter instance
> + * @mode: powr mode value
> + *
> + * Returns 0 on success, non-zero value on failure  */ static int
> +ufshcd_uic_change_pwr_mode(struct ufs_hba *hba, u8 mode) {
> +	struct uic_command uic_cmd = {0};
> +
> +	uic_cmd.command = UIC_CMD_DME_SET;
> +	uic_cmd.argument1 = UIC_ARG_MIB(PA_PWRMODE);
> +	uic_cmd.argument3 = mode;
> +
> +	return ufshcd_uic_pwr_ctrl(hba, &uic_cmd); }
> +
> +static int ufshcd_uic_hibern8_enter(struct ufs_hba *hba) {
> +	struct uic_command uic_cmd = {0};
> +
> +	uic_cmd.command = UIC_CMD_DME_HIBER_ENTER;
> +
> +	return ufshcd_uic_pwr_ctrl(hba, &uic_cmd); }
> +
> +static int ufshcd_uic_hibern8_exit(struct ufs_hba *hba) {
> +	struct uic_command uic_cmd = {0};
> +	int ret;
> +
> +	uic_cmd.command = UIC_CMD_DME_HIBER_EXIT;
> +	ret = ufshcd_uic_pwr_ctrl(hba, &uic_cmd);
> +	if (ret) {
> +		ufshcd_set_link_off(hba);
> +		ret = ufshcd_host_reset_and_restore(hba);
> +	}
> +
> +	return ret;
> +}
> +
> +/**
>   * ufshcd_config_max_pwr_mode - Set & Change power mode with
>   *	maximum capability attribute information.
>   * @hba: per adapter instance
> @@ -2034,6 +2131,9 @@ static int ufshcd_hba_enable(struct ufs_hba *hba)
>  		msleep(5);
>  	}
> 
> +	/* UniPro link is disabled at this point */
> +	ufshcd_set_link_off(hba);
> +
>  	if (hba->vops && hba->vops->hce_enable_notify)
>  		hba->vops->hce_enable_notify(hba, PRE_CHANGE);
> 
> @@ -2066,7 +2166,7 @@ static int ufshcd_hba_enable(struct ufs_hba *hba)
>  	}
> 
>  	/* enable UIC related interrupts */
> -	ufshcd_enable_intr(hba, UIC_COMMAND_COMPL);
> +	ufshcd_enable_intr(hba, UFSHCD_UIC_MASK);
> 
>  	if (hba->vops && hba->vops->hce_enable_notify)
>  		hba->vops->hce_enable_notify(hba, POST_CHANGE); @@ -2195,6
> +2295,62 @@ static void ufshcd_set_queue_depth(struct scsi_device *sdev)
>  	scsi_activate_tcq(sdev, lun_qdepth);
>  }
> 
> +/*
> + * ufshcd_get_lu_wp - returns the "b_lu_write_protect" from UNIT
> +DESCRIPTOR
> + * @hba: per-adapter instance
> + * @lun: UFS device lun id
> + * @b_lu_write_protect: pointer to buffer to hold the LU's write
> +protect info
> + *
> + * Returns 0 in case of success and b_lu_write_protect status would be
> +returned
> + * @b_lu_write_protect parameter.
> + * Returns -ENOTSUPP if reading b_lu_write_protect is not supported.
> + * Returns -EINVAL in case of invalid parameters passed to this function.
> + */
> +static int ufshcd_get_lu_wp(struct ufs_hba *hba,
> +			    u8 lun,
> +			    u8 *b_lu_write_protect)
> +{
> +	int ret;
> +
> +	if (!b_lu_write_protect)
> +		ret = -EINVAL;
> +	/*
> +	 * According to UFS device spec, RPMB LU can't be write
> +	 * protected so skip reading bLUWriteProtect parameter for
> +	 * it. For other W-LUs, UNIT DESCRIPTOR is not available.
> +	 */
> +	else if (lun >= UFS_UPIU_MAX_GENERAL_LUN)
> +		ret = -ENOTSUPP;
> +	else
> +		ret = ufshcd_read_unit_desc_param(hba,
> +					  lun,
> +					  UNIT_DESC_PARAM_LU_WR_PROTECT,
> +					  b_lu_write_protect,
> +					  sizeof(*b_lu_write_protect));
> +	return ret;
> +}
> +
> +/**
> + * ufshcd_get_lu_power_on_wp_status - get LU's power on write protect
> + * status
> + * @hba: per-adapter instance
> + * @sdev: pointer to SCSI device
> + *
> + */
> +static inline void ufshcd_get_lu_power_on_wp_status(struct ufs_hba *hba,
> +						    struct scsi_device *sdev)
> +{
> +	if (hba->dev_info.f_power_on_wp_en &&
> +	    !hba->dev_info.is_lu_power_on_wp) {
> +		u8 b_lu_write_protect;
> +
> +		if (!ufshcd_get_lu_wp(hba, ufshcd_scsi_to_upiu_lun(sdev->lun),
> +				      &b_lu_write_protect) &&
> +		    (b_lu_write_protect == UFS_LU_POWER_ON_WP))
> +			hba->dev_info.is_lu_power_on_wp = true;
> +	}
> +}
> +
>  /**
>   * ufshcd_slave_alloc - handle initial SCSI device configurations
>   * @sdev: pointer to SCSI device
> @@ -2221,6 +2377,21 @@ static int ufshcd_slave_alloc(struct scsi_device
> *sdev)
> 
>  	ufshcd_set_queue_depth(sdev);
> 
> +	ufshcd_get_lu_power_on_wp_status(hba, sdev);
> +
> +	/*
> +	 * For selecting the UFS device power mode (Active / UFS_Sleep /
> +	 * UFS_PowerDown), SCSI power management command (START STOP
> UNIT)
> +	 * needs to be sent to a "UFS device" Well known Logical Unit (W-LU).
> +	 * As this command would be sent during the UFS host controller
> +	 * runtime/system PM callbacks, we need a reference to "scsi_device"
> +	 * associated to "UFS device" W-LU. This change saves the "scsi_device"
> +	 * reference for "UFS device" W-LU during slave_configure() callback
> +	 * from SCSI mid layer.
> +	 */
> +	if (ufshcd_scsi_to_upiu_lun(sdev->lun) == UFS_UPIU_UFS_DEVICE_WLUN)
> +		hba->sdev_ufs_device = sdev;
> +
>  	return 0;
>  }
> 
> @@ -2451,8 +2622,8 @@ static void ufshcd_uic_cmd_compl(struct ufs_hba
> *hba, u32 intr_status)
>  		complete(&hba->active_uic_cmd->done);
>  	}
> 
> -	if ((intr_status & UIC_POWER_MODE) && hba->pwr_done)
> -		complete(hba->pwr_done);
> +	if ((intr_status & UFSHCD_UIC_PWR_MASK) && hba->uic_async_done)
> +		complete(hba->uic_async_done);
>  }
> 
>  /**
> @@ -2664,33 +2835,62 @@ static inline int ufshcd_get_bkops_status(struct
> ufs_hba *hba, u32 *status)  }
> 
>  /**
> - * ufshcd_urgent_bkops - handle urgent bkops exception event
> + * ufshcd_bkops_ctrl - control the auto bkops based on current bkops
> + status
>   * @hba: per-adapter instance
> + * @status: bkops_status value
>   *
> - * Enable fBackgroundOpsEn flag in the device to permit background
> - * operations.
> + * Read the bkops_status from the UFS device and Enable
> + fBackgroundOpsEn
> + * flag in the device to permit background operations if the device
> + * bkops_status is greater than or equal to "status" argument passed to
> + * this function, disable otherwise.
> + *
> + * Returns 0 for success, non-zero in case of failure.
> + *
> + * NOTE: Caller of this function can check the
> + "hba->auto_bkops_enabled" flag
> + * to know whether auto bkops is enabled or disabled after this
> + function
> + * returns control to it.
>   */
> -static int ufshcd_urgent_bkops(struct ufs_hba *hba)
> +static int ufshcd_bkops_ctrl(struct ufs_hba *hba,
> +			     enum bkops_status status)
>  {
>  	int err;
> -	u32 status = 0;
> +	u32 curr_status = 0;
> 
> -	err = ufshcd_get_bkops_status(hba, &status);
> +	err = ufshcd_get_bkops_status(hba, &curr_status);
>  	if (err) {
>  		dev_err(hba->dev, "%s: failed to get BKOPS status %d\n",
>  				__func__, err);
>  		goto out;
> +	} else if (curr_status > BKOPS_STATUS_MAX) {
> +		dev_err(hba->dev, "%s: invalid BKOPS status %d\n",
> +				__func__, curr_status);
> +		err = -EINVAL;
> +		goto out;
>  	}
> 
> -	status = status & 0xF;
> -
> -	/* handle only if status indicates performance impact or critical */
> -	if (status >= BKOPS_STATUS_PERF_IMPACT)
> +	if (curr_status >= status)
>  		err = ufshcd_enable_auto_bkops(hba);
> +	else
> +		err = ufshcd_disable_auto_bkops(hba);
>  out:
>  	return err;
>  }
> 
> +/**
> + * ufshcd_urgent_bkops - handle urgent bkops exception event
> + * @hba: per-adapter instance
> + *
> + * Enable fBackgroundOpsEn flag in the device to permit background
> + * operations.
> + *
> + * If BKOPs is enabled, this function returns 0, 1 if the bkops in not
> +enabled
> + * and negative error value for any other failure.
> + */
> +static int ufshcd_urgent_bkops(struct ufs_hba *hba) {
> +	return ufshcd_bkops_ctrl(hba, BKOPS_STATUS_PERF_IMPACT); }
> +
>  static inline int ufshcd_get_ee_status(struct ufs_hba *hba, u32 *status)  {
>  	return ufshcd_query_attr(hba, UPIU_QUERY_OPCODE_READ_ATTR, @@
> -2722,7 +2922,7 @@ static void ufshcd_exception_event_handler(struct
> work_struct *work)
>  	status &= hba->ee_ctrl_mask;
>  	if (status & MASK_EE_URGENT_BKOPS) {
>  		err = ufshcd_urgent_bkops(hba);
> -		if (err)
> +		if (err < 0)
>  			dev_err(hba->dev, "%s: failed to handle urgent bkops %d\n",
>  					__func__, err);
>  	}
> @@ -3441,7 +3641,8 @@ static int ufshcd_probe_hba(struct ufs_hba *hba)
>  	if (ret)
>  		goto out;
> 
> -	ufshcd_config_max_pwr_mode(hba);
> +	/* UniPro link is active now */
> +	ufshcd_set_link_active(hba);
> 
>  	ret = ufshcd_verify_dev_init(hba);
>  	if (ret)
> @@ -3451,14 +3652,29 @@ static int ufshcd_probe_hba(struct ufs_hba *hba)
>  	if (ret)
>  		goto out;
> 
> +	/* UFS device is also active now */
> +	ufshcd_set_ufs_dev_active(hba);
>  	ufshcd_force_reset_auto_bkops(hba);
>  	hba->ufshcd_state = UFSHCD_STATE_OPERATIONAL;
> +	hba->wlun_dev_clr_ua = true;
> +
> +	ufshcd_config_max_pwr_mode(hba);
> +
> +	/*
> +	 * If we are in error handling context or in power management callbacks
> +	 * context, no need to scan the host
> +	 */
> +	if (!ufshcd_eh_in_progress(hba) && !hba->pm_op_in_progress) {
> +		bool flag;
> +
> +		/* clear any previous UFS device information */
> +		memset(&hba->dev_info, 0, sizeof(hba->dev_info));
> +		if (!ufshcd_query_flag(hba, UPIU_QUERY_OPCODE_READ_FLAG,
> +				       QUERY_FLAG_IDN_PWR_ON_WPE, &flag))
> +			hba->dev_info.f_power_on_wp_en = flag;
> 
> -	/* If we are in error handling context no need to scan the host */
> -	if (!ufshcd_eh_in_progress(hba)) {
>  		if (!hba->is_init_prefetch)
>  			ufshcd_init_icc_levels(hba);
> -
>  		scsi_scan_host(hba->host);
>  		pm_runtime_put_sync(hba->dev);
>  	}
> @@ -3471,8 +3687,10 @@ out:
>  	 * If we failed to initialize the device or the device is not
>  	 * present, turn off the power/clocks etc.
>  	 */
> -	if (ret && !ufshcd_eh_in_progress(hba))
> +	if (ret && !ufshcd_eh_in_progress(hba) && !hba->pm_op_in_progress) {
> +		pm_runtime_put_sync(hba->dev);
>  		ufshcd_hba_exit(hba);
> +	}
> 
>  	return ret;
>  }
> @@ -3507,6 +3725,42 @@ static struct scsi_host_template
> ufshcd_driver_template = {
>  	.can_queue		= UFSHCD_CAN_QUEUE,
>  };
> 
> +static int ufshcd_config_vreg_load(struct device *dev, struct ufs_vreg *vreg,
> +				   int ua)
> +{
> +	int ret = 0;
> +	struct regulator *reg = vreg->reg;
> +	const char *name = vreg->name;
> +
> +	BUG_ON(!vreg);

For the UFS host controller driver, which doesn't have the ufs_vreg structure for vcc and vccq, this function can cause kernel panic due to this BUG_ON(). Any reason to put a BUG_ON here instead of a NULL pointer checking?

Thanks
Chuanxiao

> +
> +	ret = regulator_set_optimum_mode(reg, ua);
> +	if (ret >= 0) {
> +		/*
> +		 * regulator_set_optimum_mode() returns new regulator
> +		 * mode upon success.
> +		 */
> +		ret = 0;
> +	} else {
> +		dev_err(dev, "%s: %s set optimum mode(ua=%d) failed, err=%d\n",
> +				__func__, name, ua, ret);
> +	}
> +
> +	return ret;
> +}
> +
> +static inline int ufshcd_config_vreg_lpm(struct ufs_hba *hba,
> +					 struct ufs_vreg *vreg)
> +{
> +	return ufshcd_config_vreg_load(hba->dev, vreg,
> UFS_VREG_LPM_LOAD_UA);
> +}
> +
> +static inline int ufshcd_config_vreg_hpm(struct ufs_hba *hba,
> +					 struct ufs_vreg *vreg)
> +{
> +	return ufshcd_config_vreg_load(hba->dev, vreg, vreg->max_uA); }
> +
>  static int ufshcd_config_vreg(struct device *dev,
>  		struct ufs_vreg *vreg, bool on)
>  {
> @@ -3527,18 +3781,9 @@ static int ufshcd_config_vreg(struct device *dev,
>  		}
> 
>  		uA_load = on ? vreg->max_uA : 0;
> -		ret = regulator_set_optimum_mode(reg, uA_load);
> -		if (ret >= 0) {
> -			/*
> -			 * regulator_set_optimum_mode() returns new regulator
> -			 * mode upon success.
> -			 */
> -			ret = 0;
> -		} else {
> -			dev_err(dev, "%s: %s set optimum mode(uA_load=%d) failed,
> err=%d\n",
> -					__func__, name, uA_load, ret);
> +		ret = ufshcd_config_vreg_load(dev, vreg, uA_load);
> +		if (ret)
>  			goto out;
> -		}
>  	}
>  out:
>  	return ret;
> @@ -3654,7 +3899,8 @@ out:
>  	return ret;
>  }
> 
> -static int ufshcd_setup_clocks(struct ufs_hba *hba, bool on)
> +static int __ufshcd_setup_clocks(struct ufs_hba *hba, bool on,
> +				 bool skip_ref_clk)
>  {
>  	int ret = 0;
>  	struct ufs_clk_info *clki;
> @@ -3665,6 +3911,9 @@ static int ufshcd_setup_clocks(struct ufs_hba *hba,
> bool on)
> 
>  	list_for_each_entry(clki, head, list) {
>  		if (!IS_ERR_OR_NULL(clki->clk)) {
> +			if (skip_ref_clk && !strcmp(clki->name, "ref_clk"))
> +				continue;
> +
>  			if (on && !clki->enabled) {
>  				ret = clk_prepare_enable(clki->clk);
>  				if (ret) {
> @@ -3690,6 +3939,11 @@ out:
>  	return ret;
>  }
> 
> +static int ufshcd_setup_clocks(struct ufs_hba *hba, bool on) {
> +	return  __ufshcd_setup_clocks(hba, on, false); }
> +
>  static int ufshcd_init_clocks(struct ufs_hba *hba)  {
>  	int ret = 0;
> @@ -3828,68 +4082,514 @@ static void ufshcd_hba_exit(struct ufs_hba *hba)
>  	}
>  }
> 
> +static int
> +ufshcd_send_request_sense(struct ufs_hba *hba, struct scsi_device *sdp)
> +{
> +	unsigned char cmd[6] = {REQUEST_SENSE,
> +				0,
> +				0,
> +				0,
> +				SCSI_SENSE_BUFFERSIZE,
> +				0};
> +	char *buffer;
> +	int ret;
> +
> +	buffer = kzalloc(SCSI_SENSE_BUFFERSIZE, GFP_KERNEL);
> +	if (!buffer) {
> +		ret = -ENOMEM;
> +		goto out;
> +	}
> +
> +	ret = scsi_execute_req_flags(sdp, cmd, DMA_FROM_DEVICE, buffer,
> +				SCSI_SENSE_BUFFERSIZE, NULL,
> +				msecs_to_jiffies(1000), 3, NULL, REQ_PM);
> +	if (ret)
> +		pr_err("%s: failed with err %d\n", __func__, ret);
> +
> +	kfree(buffer);
> +out:
> +	return ret;
> +}
> +
>  /**
> - * ufshcd_suspend - suspend power management function
> + * ufshcd_set_dev_pwr_mode - sends START STOP UNIT command to set
> device
> + *			     power mode
>   * @hba: per adapter instance
> - * @state: power state
> + * @pwr_mode: device power mode to set
>   *
> - * Returns -ENOSYS
> + * Returns 0 if requested power mode is set successfully
> + * Returns non-zero if failed to set the requested power mode
>   */
> -int ufshcd_suspend(struct ufs_hba *hba, pm_message_t state)
> +static int ufshcd_set_dev_pwr_mode(struct ufs_hba *hba,
> +				     enum ufs_dev_pwr_mode pwr_mode)
>  {
> +	unsigned char cmd[6] = { START_STOP };
> +	struct scsi_sense_hdr sshdr;
> +	struct scsi_device *sdp = hba->sdev_ufs_device;
> +	int ret;
> +
> +	if (!sdp || !scsi_device_online(sdp))
> +		return -ENODEV;
> +
> +	/*
> +	 * If scsi commands fail, the scsi mid-layer schedules scsi error-
> +	 * handling, which would wait for host to be resumed. Since we know
> +	 * we are functional while we are here, skip host resume in error
> +	 * handling context.
> +	 */
> +	hba->host->eh_noresume = 1;
> +	if (hba->wlun_dev_clr_ua) {
> +		ret = ufshcd_send_request_sense(hba, sdp);
> +		if (ret)
> +			goto out;
> +		/* Unit attention condition is cleared now */
> +		hba->wlun_dev_clr_ua = false;
> +	}
> +
> +	cmd[4] = pwr_mode << 4;
> +
>  	/*
> -	 * TODO:
> -	 * 1. Block SCSI requests from SCSI midlayer
> -	 * 2. Change the internal driver state to non operational
> -	 * 3. Set UTRLRSR and UTMRLRSR bits to zero
> -	 * 4. Wait until outstanding commands are completed
> -	 * 5. Set HCE to zero to send the UFS host controller to reset state
> +	 * Current function would be generally called from the power
> management
> +	 * callbacks hence set the REQ_PM flag so that it doesn't resume the
> +	 * already suspended childs.
>  	 */
> +	ret = scsi_execute_req_flags(sdp, cmd, DMA_NONE, NULL, 0, &sshdr,
> +				     START_STOP_TIMEOUT, 0, NULL, REQ_PM);
> +	if (ret) {
> +		sdev_printk(KERN_WARNING, sdp,
> +			  "START_STOP failed for power mode: %d\n", pwr_mode);
> +		scsi_show_result(ret);
> +		if (driver_byte(ret) & DRIVER_SENSE) {
> +			scsi_show_sense_hdr(&sshdr);
> +			scsi_show_extd_sense(sshdr.asc, sshdr.ascq);
> +		}
> +	}
> 
> -	return -ENOSYS;
> +	if (!ret)
> +		hba->curr_dev_pwr_mode = pwr_mode;
> +out:
> +	hba->host->eh_noresume = 0;
> +	return ret;
> +}
> +
> +static int ufshcd_link_state_transition(struct ufs_hba *hba,
> +					enum uic_link_state req_link_state,
> +					int check_for_bkops)
> +{
> +	int ret = 0;
> +
> +	if (req_link_state == hba->uic_link_state)
> +		return 0;
> +
> +	if (req_link_state == UIC_LINK_HIBERN8_STATE) {
> +		ret = ufshcd_uic_hibern8_enter(hba);
> +		if (!ret)
> +			ufshcd_set_link_hibern8(hba);
> +		else
> +			goto out;
> +	}
> +	/*
> +	 * If autobkops is enabled, link can't be turned off because
> +	 * turning off the link would also turn off the device.
> +	 */
> +	else if ((req_link_state == UIC_LINK_OFF_STATE) &&
> +		   (!check_for_bkops || (check_for_bkops &&
> +		    !hba->auto_bkops_enabled))) {
> +		/*
> +		 * Change controller state to "reset state" which
> +		 * should also put the link in off/reset state
> +		 */
> +		ufshcd_hba_stop(hba);
> +		/*
> +		 * TODO: Check if we need any delay to make sure that
> +		 * controller is reset
> +		 */
> +		ufshcd_set_link_off(hba);
> +	}
> +
> +out:
> +	return ret;
> +}
> +
> +static void ufshcd_vreg_set_lpm(struct ufs_hba *hba) {
> +	/*
> +	 * If UFS device is either in UFS_Sleep turn off VCC rail to save some
> +	 * power.
> +	 *
> +	 * If UFS device and link is in OFF state, all power supplies (VCC,
> +	 * VCCQ, VCCQ2) can be turned off if power on write protect is not
> +	 * required. If UFS link is inactive (Hibern8 or OFF state) and device
> +	 * is in sleep state, put VCCQ & VCCQ2 rails in LPM mode.
> +	 *
> +	 * Ignore the error returned by ufshcd_toggle_vreg() as device is anyway
> +	 * in low power state which would save some power.
> +	 */
> +	if (ufshcd_is_ufs_dev_poweroff(hba) && ufshcd_is_link_off(hba) &&
> +	    !hba->dev_info.is_lu_power_on_wp) {
> +		ufshcd_setup_vreg(hba, false);
> +	} else if (!ufshcd_is_ufs_dev_active(hba)) {
> +		ufshcd_toggle_vreg(hba->dev, hba->vreg_info.vcc, false);
> +		if (!ufshcd_is_link_active(hba)) {
> +			ufshcd_config_vreg_lpm(hba, hba->vreg_info.vccq);
> +			ufshcd_config_vreg_lpm(hba, hba->vreg_info.vccq2);
> +		}
> +	}
> +}
> +
> +static int ufshcd_vreg_set_hpm(struct ufs_hba *hba) {
> +	int ret = 0;
> +
> +	if (ufshcd_is_ufs_dev_poweroff(hba) && ufshcd_is_link_off(hba) &&
> +	    !hba->dev_info.is_lu_power_on_wp) {
> +		ret = ufshcd_setup_vreg(hba, true);
> +	} else if (!ufshcd_is_ufs_dev_active(hba)) {
> +		ret = ufshcd_toggle_vreg(hba->dev, hba->vreg_info.vcc, true);
> +		if (!ret && !ufshcd_is_link_active(hba)) {
> +			ret = ufshcd_config_vreg_hpm(hba, hba->vreg_info.vccq);
> +			if (ret)
> +				goto vcc_disable;
> +			ret = ufshcd_config_vreg_hpm(hba, hba->vreg_info.vccq2);
> +			if (ret)
> +				goto vccq_lpm;
> +		}
> +	}
> +	goto out;
> +
> +vccq_lpm:
> +	ufshcd_config_vreg_lpm(hba, hba->vreg_info.vccq);
> +vcc_disable:
> +	ufshcd_toggle_vreg(hba->dev, hba->vreg_info.vcc, false);
> +out:
> +	return ret;
>  }
> -EXPORT_SYMBOL_GPL(ufshcd_suspend);
> 
>  /**
> - * ufshcd_resume - resume power management function
> + * ufshcd_suspend - helper function for suspend operations
>   * @hba: per adapter instance
> + * @pm_op: desired low power operation type
>   *
> - * Returns -ENOSYS
> + * This function will try to put the UFS device and link into low power
> + * mode based on the "rpm_lvl" (Runtime PM level) or "spm_lvl"
> + * (System PM level).
> + *
> + * If this function is called during shutdown, it will make sure that
> + * both UFS device and UFS link is powered off.
> + *
> + * NOTE: UFS device & link must be active before we enter in this function.
> + *
> + * Returns 0 for success and non-zero for failure
>   */
> -int ufshcd_resume(struct ufs_hba *hba)
> +static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
>  {
> +	int ret = 0;
> +	enum ufs_pm_level pm_lvl;
> +	enum ufs_dev_pwr_mode req_dev_pwr_mode;
> +	enum uic_link_state req_link_state;
> +
> +	hba->pm_op_in_progress = 1;
> +	if (!ufshcd_is_shutdown_pm(pm_op)) {
> +		pm_lvl = ufshcd_is_runtime_pm(pm_op) ?
> +			 hba->rpm_lvl : hba->spm_lvl;
> +		req_dev_pwr_mode = ufs_get_pm_lvl_to_dev_pwr_mode(pm_lvl);
> +		req_link_state = ufs_get_pm_lvl_to_link_pwr_state(pm_lvl);
> +	} else {
> +		req_dev_pwr_mode = UFS_POWERDOWN_PWR_MODE;
> +		req_link_state = UIC_LINK_OFF_STATE;
> +	}
> +
> +	/*
> +	 * If we can't transition into any of the low power modes
> +	 * just gate the clocks.
> +	 */
> +	if (req_dev_pwr_mode == UFS_ACTIVE_PWR_MODE &&
> +			req_link_state == UIC_LINK_ACTIVE_STATE) {
> +		goto disable_clks;
> +	}
> +
> +	if ((req_dev_pwr_mode == hba->curr_dev_pwr_mode) &&
> +	    (req_link_state == hba->uic_link_state))
> +		goto out;
> +
> +	/* UFS device & link must be active before we enter in this function */
> +	if (!ufshcd_is_ufs_dev_active(hba) || !ufshcd_is_link_active(hba)) {
> +		ret = -EINVAL;
> +		goto out;
> +	}
> +
> +	if (ufshcd_is_runtime_pm(pm_op)) {
> +		/*
> +		 * The device is idle with no requests in the queue,
> +		 * allow background operations if needed.
> +		 */
> +		ret = ufshcd_bkops_ctrl(hba, BKOPS_STATUS_NON_CRITICAL);
> +		if (ret)
> +			goto out;
> +	}
> +
> +	if ((req_dev_pwr_mode != hba->curr_dev_pwr_mode) &&
> +	     ((ufshcd_is_runtime_pm(pm_op) && !hba->auto_bkops_enabled) ||
> +	       !ufshcd_is_runtime_pm(pm_op))) {
> +		/* ensure that bkops is disabled */
> +		ufshcd_disable_auto_bkops(hba);
> +		ret = ufshcd_set_dev_pwr_mode(hba, req_dev_pwr_mode);
> +		if (ret)
> +			goto out;
> +	}
> +
> +	ret = ufshcd_link_state_transition(hba, req_link_state, 1);
> +	if (ret)
> +		goto set_dev_active;
> +
> +	ufshcd_vreg_set_lpm(hba);
> +
> +disable_clks:
> +	/*
> +	 * Call vendor specific suspend callback. As these callbacks may access
> +	 * vendor specific host controller register space call them before the
> +	 * host clocks are ON.
> +	 */
> +	if (hba->vops && hba->vops->suspend) {
> +		ret = hba->vops->suspend(hba, pm_op);
> +		if (ret)
> +			goto set_link_active;
> +	}
> +
> +	if (hba->vops && hba->vops->setup_clocks) {
> +		ret = hba->vops->setup_clocks(hba, false);
> +		if (ret)
> +			goto vops_resume;
> +	}
> +
> +	if (!ufshcd_is_link_active(hba))
> +		ufshcd_setup_clocks(hba, false);
> +	else
> +		/* If link is active, device ref_clk can't be switched off */
> +		__ufshcd_setup_clocks(hba, false, true);
> +
>  	/*
> -	 * TODO:
> -	 * 1. Set HCE to 1, to start the UFS host controller
> -	 * initialization process
> -	 * 2. Set UTRLRSR and UTMRLRSR bits to 1
> -	 * 3. Change the internal driver state to operational
> -	 * 4. Unblock SCSI requests from SCSI midlayer
> +	 * Disable the host irq as host controller as there won't be any
> +	 * host controller trasanction expected till resume.
>  	 */
> +	ufshcd_disable_irq(hba);
> +	goto out;
> 
> -	return -ENOSYS;
> +vops_resume:
> +	if (hba->vops && hba->vops->resume)
> +		hba->vops->resume(hba, pm_op);
> +set_link_active:
> +	ufshcd_vreg_set_hpm(hba);
> +	if (ufshcd_is_link_hibern8(hba) && !ufshcd_uic_hibern8_exit(hba))
> +		ufshcd_set_link_active(hba);
> +	else if (ufshcd_is_link_off(hba))
> +		ufshcd_host_reset_and_restore(hba);
> +set_dev_active:
> +	if (!ufshcd_set_dev_pwr_mode(hba, UFS_ACTIVE_PWR_MODE))
> +		ufshcd_disable_auto_bkops(hba);
> +out:
> +	hba->pm_op_in_progress = 0;
> +	return ret;
>  }
> -EXPORT_SYMBOL_GPL(ufshcd_resume);
> 
> -int ufshcd_runtime_suspend(struct ufs_hba *hba)
> +/**
> + * ufshcd_resume - helper function for resume operations
> + * @hba: per adapter instance
> + * @pm_op: runtime PM or system PM
> + *
> + * This function basically brings the UFS device, UniPro link and
> +controller
> + * to active state.
> + *
> + * Returns 0 for success and non-zero for failure  */ static int
> +ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
>  {
> -	if (!hba)
> -		return 0;
> +	int ret;
> +	enum uic_link_state old_link_state;
> +
> +	hba->pm_op_in_progress = 1;
> +	old_link_state = hba->uic_link_state;
> +	/* Make sure clocks are enabled before accessing controller */
> +	ret = ufshcd_setup_clocks(hba, true);
> +	if (ret)
> +		goto out;
> +
> +	if (hba->vops && hba->vops->setup_clocks) {
> +		ret = hba->vops->setup_clocks(hba, true);
> +		if (ret)
> +			goto disable_clks;
> +	}
> +
> +	/* enable the host irq as host controller would be active soon */
> +	ufshcd_enable_irq(hba);
> +
> +	ret = ufshcd_vreg_set_hpm(hba);
> +	if (ret)
> +		goto disable_irq_and_vops_clks;
> 
>  	/*
> -	 * The device is idle with no requests in the queue,
> -	 * allow background operations.
> +	 * Call vendor specific resume callback. As these callbacks may access
> +	 * vendor specific host controller register space call them when the
> +	 * host clocks are ON.
>  	 */
> -	return ufshcd_enable_auto_bkops(hba);
> +	if (hba->vops && hba->vops->resume) {
> +		ret = hba->vops->resume(hba, pm_op);
> +		if (ret)
> +			goto disable_vreg;
> +	}
> +
> +	if (ufshcd_is_link_hibern8(hba)) {
> +		ret = ufshcd_uic_hibern8_exit(hba);
> +		if (!ret)
> +			ufshcd_set_link_active(hba);
> +		else
> +			goto vendor_suspend;
> +	} else if (ufshcd_is_link_off(hba)) {
> +		ret = ufshcd_host_reset_and_restore(hba);
> +		/*
> +		 * ufshcd_host_reset_and_restore() should have already
> +		 * set the link state as active
> +		 */
> +		if (ret || !ufshcd_is_link_active(hba))
> +			goto vendor_suspend;
> +	}
> +
> +	if (!ufshcd_is_ufs_dev_active(hba)) {
> +		ret = ufshcd_set_dev_pwr_mode(hba, UFS_ACTIVE_PWR_MODE);
> +		if (ret)
> +			goto set_old_link_state;
> +	}
> +
> +	ufshcd_disable_auto_bkops(hba);
> +	goto out;
> +
> +set_old_link_state:
> +	ufshcd_link_state_transition(hba, old_link_state, 0);
> +vendor_suspend:
> +	if (hba->vops && hba->vops->suspend)
> +		hba->vops->suspend(hba, pm_op);
> +disable_vreg:
> +	ufshcd_vreg_set_lpm(hba);
> +disable_irq_and_vops_clks:
> +	ufshcd_disable_irq(hba);
> +	if (hba->vops && hba->vops->setup_clocks)
> +		ret = hba->vops->setup_clocks(hba, false);
> +disable_clks:
> +	ufshcd_setup_clocks(hba, false);
> +out:
> +	hba->pm_op_in_progress = 0;
> +	return ret;
> +}
> +
> +/**
> + * ufshcd_system_suspend - system suspend routine
> + * @hba: per adapter instance
> + * @pm_op: runtime PM or system PM
> + *
> + * Check the description of ufshcd_suspend() function for more details.
> + *
> + * Returns 0 for success and non-zero for failure  */ int
> +ufshcd_system_suspend(struct ufs_hba *hba) {
> +	int ret = 0;
> +
> +	if (!hba || !hba->is_powered)
> +		goto out;
> +
> +	if (pm_runtime_suspended(hba->dev)) {
> +		if (hba->rpm_lvl == hba->spm_lvl)
> +			/*
> +			 * There is possibility that device may still be in
> +			 * active state during the runtime suspend.
> +			 */
> +			if ((ufs_get_pm_lvl_to_dev_pwr_mode(hba->spm_lvl) ==
> +			    hba->curr_dev_pwr_mode)
> && !hba->auto_bkops_enabled)
> +				goto out;
> +
> +		/*
> +		 * UFS device and/or UFS link low power states during runtime
> +		 * suspend seems to be different than what is expected during
> +		 * system suspend. Hence runtime resume the devic & link and
> +		 * let the system suspend low power states to take effect.
> +		 * TODO: If resume takes longer time, we might have optimize
> +		 * it in future by not resuming everything if possible.
> +		 */
> +		ret = ufshcd_runtime_resume(hba);
> +		if (ret)
> +			goto out;
> +	}
> +
> +	ret = ufshcd_suspend(hba, UFS_SYSTEM_PM);
> +out:
> +	return ret;
> +}
> +EXPORT_SYMBOL(ufshcd_system_suspend);
> +
> +/**
> + * ufshcd_system_resume - system resume routine
> + * @hba: per adapter instance
> + *
> + * Returns 0 for success and non-zero for failure  */
> +
> +int ufshcd_system_resume(struct ufs_hba *hba) {
> +	if (!hba || !hba->is_powered || pm_runtime_suspended(hba->dev))
> +		/*
> +		 * Let the runtime resume take care of resuming
> +		 * if runtime suspended.
> +		 */
> +		return 0;
> +	else
> +		return ufshcd_resume(hba, UFS_SYSTEM_PM); }
> +EXPORT_SYMBOL(ufshcd_system_resume);
> +
> +/**
> + * ufshcd_runtime_suspend - runtime suspend routine
> + * @hba: per adapter instance
> + *
> + * Check the description of ufshcd_suspend() function for more details.
> + *
> + * Returns 0 for success and non-zero for failure  */ int
> +ufshcd_runtime_suspend(struct ufs_hba *hba) {
> +	if (!hba || !hba->is_powered)
> +		return 0;
> +	else
> +		return ufshcd_suspend(hba, UFS_RUNTIME_PM);
>  }
>  EXPORT_SYMBOL(ufshcd_runtime_suspend);
> 
> +/**
> + * ufshcd_runtime_resume - runtime resume routine
> + * @hba: per adapter instance
> + *
> + * This function basically brings the UFS device, UniPro link and
> +controller
> + * to active state. Following operations are done in this function:
> + *
> + * 1. Turn on all the controller related clocks
> + * 2. Bring the UniPro link out of Hibernate state
> + * 3. If UFS device is in sleep state, turn ON VCC rail and bring the UFS device
> + *    to active state.
> + * 4. If auto-bkops is enabled on the device, disable it.
> + *
> + * So following would be the possible power state after this function
> +return
> + * successfully:
> + *	S1: UFS device in Active state with VCC rail ON
> + *	    UniPro link in Active state
> + *	    All the UFS/UniPro controller clocks are ON
> + *
> + * Returns 0 for success and non-zero for failure  */
>  int ufshcd_runtime_resume(struct ufs_hba *hba)  {
> -	if (!hba)
> +	if (!hba || !hba->is_powered)
>  		return 0;
> -
> -	return ufshcd_disable_auto_bkops(hba);
> +	else
> +		return ufshcd_resume(hba, UFS_RUNTIME_PM);
>  }
>  EXPORT_SYMBOL(ufshcd_runtime_resume);
> 
> @@ -3900,6 +4600,36 @@ int ufshcd_runtime_idle(struct ufs_hba *hba)
> EXPORT_SYMBOL(ufshcd_runtime_idle);
> 
>  /**
> + * ufshcd_shutdown - shutdown routine
> + * @hba: per adapter instance
> + *
> + * This function would power off both UFS device and UFS link.
> + *
> + * Returns 0 always to allow force shutdown even in case of errors.
> + */
> +int ufshcd_shutdown(struct ufs_hba *hba) {
> +	int ret = 0;
> +
> +	if (ufshcd_is_ufs_dev_poweroff(hba) && ufshcd_is_link_off(hba))
> +		goto out;
> +
> +	if (pm_runtime_suspended(hba->dev)) {
> +		ret = ufshcd_runtime_resume(hba);
> +		if (ret)
> +			goto out;
> +	}
> +
> +	ret = ufshcd_suspend(hba, UFS_SHUTDOWN_PM);
> +out:
> +	if (ret)
> +		dev_err(hba->dev, "%s failed, err %d\n", __func__, ret);
> +	/* allow force shutdown even in case of errors */
> +	return 0;
> +}
> +EXPORT_SYMBOL(ufshcd_shutdown);
> +
> +/**
>   * ufshcd_remove - de-allocate SCSI host and host memory space
>   *		data structure memory
>   * @hba - per adapter instance
> @@ -4052,6 +4782,8 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem
> *mmio_base, unsigned int irq)
>  	if (err) {
>  		dev_err(hba->dev, "request irq failed\n");
>  		goto out_disable;
> +	} else {
> +		hba->is_irq_enabled = true;
>  	}
> 
>  	/* Enable SCSI tag mapping */
> @@ -4077,6 +4809,12 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem
> *mmio_base, unsigned int irq)
>  	/* Hold auto suspend until async scan completes */
>  	pm_runtime_get_sync(dev);
> 
> +	/*
> +	 * The device-initialize-sequence hasn't been invoked yet.
> +	 * Set the device to power-off state
> +	 */
> +	ufshcd_set_ufs_dev_poweroff(hba);
> +
>  	async_schedule(ufshcd_async_scan, hba);
> 
>  	return 0;
> @@ -4084,6 +4822,7 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem
> *mmio_base, unsigned int irq)
>  out_remove_scsi_host:
>  	scsi_remove_host(hba->host);
>  out_disable:
> +	hba->is_irq_enabled = false;
>  	scsi_host_put(host);
>  	ufshcd_hba_exit(hba);
>  out_error:
> diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h index
> 9b5f77f..1ee429d 100644
> --- a/drivers/scsi/ufs/ufshcd.h
> +++ b/drivers/scsi/ufs/ufshcd.h
> @@ -96,6 +96,54 @@ struct uic_command {
>  	struct completion done;
>  };
> 
> +/* Used to differentiate the power management options */ enum ufs_pm_op
> +{
> +	UFS_RUNTIME_PM,
> +	UFS_SYSTEM_PM,
> +	UFS_SHUTDOWN_PM,
> +};
> +
> +#define ufshcd_is_runtime_pm(op) ((op) == UFS_RUNTIME_PM) #define
> +ufshcd_is_system_pm(op) ((op) == UFS_SYSTEM_PM) #define
> +ufshcd_is_shutdown_pm(op) ((op) == UFS_SHUTDOWN_PM)
> +
> +/* Host <-> Device UniPro Link state */ enum uic_link_state {
> +	UIC_LINK_OFF_STATE	= 0, /* Link powered down or disabled */
> +	UIC_LINK_ACTIVE_STATE	= 1, /* Link is in Fast/Slow/Sleep state */
> +	UIC_LINK_HIBERN8_STATE	= 2, /* Link is in Hibernate state */
> +};
> +
> +#define ufshcd_is_link_off(hba) ((hba)->uic_link_state ==
> +UIC_LINK_OFF_STATE) #define ufshcd_is_link_active(hba)
> ((hba)->uic_link_state == \
> +				    UIC_LINK_ACTIVE_STATE)
> +#define ufshcd_is_link_hibern8(hba) ((hba)->uic_link_state == \
> +				    UIC_LINK_HIBERN8_STATE)
> +#define ufshcd_set_link_off(hba) ((hba)->uic_link_state =
> +UIC_LINK_OFF_STATE) #define ufshcd_set_link_active(hba)
> ((hba)->uic_link_state = \
> +				    UIC_LINK_ACTIVE_STATE)
> +#define ufshcd_set_link_hibern8(hba) ((hba)->uic_link_state = \
> +				    UIC_LINK_HIBERN8_STATE)
> +
> +/*
> + * UFS Power management levels.
> + * Each level is in increasing order of power savings.
> + */
> +enum ufs_pm_level {
> +	UFS_PM_LVL_0, /* UFS_ACTIVE_PWR_MODE, UIC_LINK_ACTIVE_STATE
> */
> +	UFS_PM_LVL_1, /* UFS_ACTIVE_PWR_MODE, UIC_LINK_HIBERN8_STATE
> */
> +	UFS_PM_LVL_2, /* UFS_SLEEP_PWR_MODE, UIC_LINK_ACTIVE_STATE */
> +	UFS_PM_LVL_3, /* UFS_SLEEP_PWR_MODE, UIC_LINK_HIBERN8_STATE
> */
> +	UFS_PM_LVL_4, /* UFS_POWERDOWN_PWR_MODE,
> UIC_LINK_HIBERN8_STATE */
> +	UFS_PM_LVL_5, /* UFS_POWERDOWN_PWR_MODE,
> UIC_LINK_OFF_STATE */
> +	UFS_PM_LVL_MAX
> +};
> +
> +struct ufs_pm_lvl_states {
> +	enum ufs_dev_pwr_mode dev_state;
> +	enum uic_link_state link_state;
> +};
> +
>  /**
>   * struct ufshcd_lrb - local reference block
>   * @utr_descriptor_ptr: UTRD address of the command @@ -184,6 +232,8
> @@ struct ufs_clk_info {
>   *                     variant specific Uni-Pro initialization.
>   * @link_startup_notify: called before and after Link startup is carried out
>   *                       to allow variant specific Uni-Pro initialization.
> + * @suspend: called during host controller PM callback
> + * @resume: called during host controller PM callback
>   */
>  struct ufs_hba_variant_ops {
>  	const char *name;
> @@ -193,6 +243,8 @@ struct ufs_hba_variant_ops {
>  	int     (*setup_regulators)(struct ufs_hba *, bool);
>  	int     (*hce_enable_notify)(struct ufs_hba *, bool);
>  	int     (*link_startup_notify)(struct ufs_hba *, bool);
> +	int     (*suspend)(struct ufs_hba *, enum ufs_pm_op);
> +	int     (*resume)(struct ufs_hba *, enum ufs_pm_op);
>  };
> 
>  /**
> @@ -271,6 +323,13 @@ struct ufs_hba {
>  	 * "UFS device" W-LU.
>  	 */
>  	struct scsi_device *sdev_ufs_device;
> +	enum ufs_dev_pwr_mode curr_dev_pwr_mode;
> +	enum uic_link_state uic_link_state;
> +	/* Desired UFS power management level during runtime PM */
> +	enum ufs_pm_level rpm_lvl;
> +	/* Desired UFS power management level during system PM */
> +	enum ufs_pm_level spm_lvl;
> +	int pm_op_in_progress;
> 
>  	struct ufshcd_lrb *lrb;
>  	unsigned long lrb_in_use;
> @@ -285,16 +344,17 @@ struct ufs_hba {
>  	struct ufs_hba_variant_ops *vops;
>  	void *priv;
>  	unsigned int irq;
> +	bool is_irq_enabled;
> 
> -	struct uic_command *active_uic_cmd;
> -	struct mutex uic_cmd_mutex;
> 
>  	wait_queue_head_t tm_wq;
>  	wait_queue_head_t tm_tag_wq;
>  	unsigned long tm_condition;
>  	unsigned long tm_slots_in_use;
> 
> -	struct completion *pwr_done;
> +	struct uic_command *active_uic_cmd;
> +	struct mutex uic_cmd_mutex;
> +	struct completion *uic_async_done;
> 
>  	u32 ufshcd_state;
>  	u32 eh_flags;
> @@ -317,9 +377,13 @@ struct ufs_hba {
>  	/* Device management request data */
>  	struct ufs_dev_cmd dev_cmd;
> 
> +	/* Keeps information of the UFS device connected to this host */
> +	struct ufs_dev_info dev_info;
>  	bool auto_bkops_enabled;
>  	struct ufs_vreg_info vreg_info;
>  	struct list_head clk_list_head;
> +
> +	bool wlun_dev_clr_ua;
>  };
> 
>  #define ufshcd_writel(hba, val, reg)	\
> @@ -346,11 +410,12 @@ static inline void check_upiu_size(void)
>  		GENERAL_UPIU_REQUEST_SIZE + QUERY_DESC_MAX_SIZE);  }
> 
> -extern int ufshcd_suspend(struct ufs_hba *hba, pm_message_t state);
> -extern int ufshcd_resume(struct ufs_hba *hba);  extern int
> ufshcd_runtime_suspend(struct ufs_hba *hba);  extern int
> ufshcd_runtime_resume(struct ufs_hba *hba);  extern int
> ufshcd_runtime_idle(struct ufs_hba *hba);
> +extern int ufshcd_system_suspend(struct ufs_hba *hba); extern int
> +ufshcd_system_resume(struct ufs_hba *hba); extern int
> +ufshcd_shutdown(struct ufs_hba *hba);
>  extern int ufshcd_dme_set_attr(struct ufs_hba *hba, u32 attr_sel,
>  			       u8 attr_set, u32 mib_val, u8 peer);  extern int
> ufshcd_dme_get_attr(struct ufs_hba *hba, u32 attr_sel, diff --git
> a/drivers/scsi/ufs/ufshci.h b/drivers/scsi/ufs/ufshci.h index e1b844b..d572119
> 100644
> --- a/drivers/scsi/ufs/ufshci.h
> +++ b/drivers/scsi/ufs/ufshci.h
> @@ -124,8 +124,11 @@ enum {
>  #define CONTROLLER_FATAL_ERROR			UFS_BIT(16)
>  #define SYSTEM_BUS_FATAL_ERROR			UFS_BIT(17)
> 
> -#define UFSHCD_UIC_MASK		(UIC_COMMAND_COMPL |\
> -				 UIC_POWER_MODE)
> +#define UFSHCD_UIC_PWR_MASK	(UIC_HIBERNATE_ENTER |\
> +				UIC_HIBERNATE_EXIT |\
> +				UIC_POWER_MODE)
> +
> +#define UFSHCD_UIC_MASK		(UIC_COMMAND_COMPL |
> UFSHCD_UIC_PWR_MASK)
> 
>  #define UFSHCD_ERROR_MASK	(UIC_ERROR |\
>  				DEVICE_FATAL_ERROR |\
> @@ -210,7 +213,7 @@ enum {
>  #define UIC_GET_ATTR_ID(v)		(((v) >> 16) & 0xFFFF)
> 
>  /* UIC Commands */
> -enum {
> +enum uic_cmd_dme {
>  	UIC_CMD_DME_GET			= 0x01,
>  	UIC_CMD_DME_SET			= 0x02,
>  	UIC_CMD_DME_PEER_GET		= 0x03,
> --
> 1.8.5.2
> --
> QUALCOMM ISRAEL, on behalf of Qualcomm Innovation Center, Inc. is a
> member of Code Aurora Forum, hosted by The Linux Foundation
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body
> of a message to majordomo@vger.kernel.org More majordomo info at
> http://vger.kernel.org/majordomo-info.html

RE: [PATCH/RFC V2 10/16] scsi: ufs: add UFS power management support

[Dong, Chuanxiao]

> -----Original Message-----
> From: linux-scsi-owner@vger.kernel.org
> [mailto:linux-scsi-owner@vger.kernel.org] On Behalf Of Dong, Chuanxiao
> Sent: Wednesday, August 20, 2014 3:21 PM
> To: Dolev Raviv; James.Bottomley@HansenPartnership.com;
> hch@infradead.org
> Cc: linux-scsi@vger.kernel.org; linux-scsi-owner@vger.kernel.org;
> linux-arm-msm@vger.kernel.org; santoshsy@gmail.com; Subhash Jadavani;
> Sujit Reddy Thumma
> Subject: RE: [PATCH/RFC V2 10/16] scsi: ufs: add UFS power management
> support
> 
> 
> 
> > -----Original Message-----
> > From: linux-scsi-owner@vger.kernel.org
> > [mailto:linux-scsi-owner@vger.kernel.org] On Behalf Of Dolev Raviv
> > Sent: Thursday, August 14, 2014 9:31 PM
> > To: James.Bottomley@HansenPartnership.com; hch@infradead.org
> > Cc: linux-scsi@vger.kernel.org; linux-scsi-owner@vger.kernel.org;
> > linux-arm-msm@vger.kernel.org; santoshsy@gmail.com; Subhash Jadavani;
> > Dolev Raviv; Sujit Reddy Thumma
> > Subject: [PATCH/RFC V2 10/16] scsi: ufs: add UFS power management support
> >
> > From: Subhash Jadavani <subhashj@codeaurora.org>
> >
> > This patch adds support for UFS device and UniPro link power management
> > during runtime/system PM.
> >
> > Main idea is to define multiple UFS low power levels based on UFS device and
> > UFS link power states. This would allow any specific platform or pci driver to
> > choose the best suited low power level during runtime and system suspend
> > based on their power goals.
> >
> > bkops handlig:
> > To put the UFS device in sleep state when bkops is disabled, first query the
> > bkops status from the device and enable bkops on device only if device needs
> > time to perform the bkops.
> >
> > START_STOP handling:
> > Before sending START_STOP_UNIT to the device well-known logical unit
> > (w-lun) to make sure that the device w-lun unit attention condition is cleared.
> >
> > Write protection:
> > UFS device specification allows LUs to be write protected, either permanently
> > or power on write protected. If any LU is power on write protected and if the
> > card is power cycled (by powering off VCCQ and/or VCC rails), LU's write
> > protect status would be lost. So this means those LUs can be written now. To
> > ensures that UFS device is power cycled only if the power on protect is not set
> > for any of the LUs, check if power on write protect is set and if device is in
> > sleep/power-off state & link in inactive state (Hibern8 or OFF state).
> > If none of the Logical Units on UFS device is power on write protected then all
> > UFS device power rails (VCC, VCCQ & VCCQ2) can be turned off if UFS device
> is
> > in power-off state and UFS link is in OFF state. But current implementation
> > would disable all device power rails even if UFS link is not in OFF state.
> >
> > Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
> > Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
> > Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
> >
> > diff --git a/drivers/scsi/ufs/ufs.h b/drivers/scsi/ufs/ufs.h index
> > bcc3a7f..2a82959 100644
> > --- a/drivers/scsi/ufs/ufs.h
> > +++ b/drivers/scsi/ufs/ufs.h
> > @@ -129,6 +129,7 @@ enum {
> >  /* Flag idn for Query Requests*/
> >  enum flag_idn {
> >  	QUERY_FLAG_IDN_FDEVICEINIT      = 0x01,
> > +	QUERY_FLAG_IDN_PWR_ON_WPE	= 0x03,
> >  	QUERY_FLAG_IDN_BKOPS_EN         = 0x04,
> >  };
> >
> > @@ -194,6 +195,18 @@ enum unit_desc_param {
> >  	UNIT_DESC_PARAM_LARGE_UNIT_SIZE_M1	= 0x22,
> >  };
> >
> > +/*
> > + * Logical Unit Write Protect
> > + * 00h: LU not write protected
> > + * 01h: LU write protected when fPowerOnWPEn =1
> > + * 02h: LU permanently write protected when fPermanentWPEn =1  */
> enum
> > +ufs_lu_wp_type {
> > +	UFS_LU_NO_WP		= 0x00,
> > +	UFS_LU_POWER_ON_WP	= 0x01,
> > +	UFS_LU_PERM_WP		= 0x02,
> > +};
> > +
> >  /* bActiveICCLevel parameter current units */  enum {
> >  	UFSHCD_NANO_AMP		= 0,
> > @@ -226,11 +239,12 @@ enum {
> >  };
> >
> >  /* Background operation status */
> > -enum {
> > +enum bkops_status {
> >  	BKOPS_STATUS_NO_OP               = 0x0,
> >  	BKOPS_STATUS_NON_CRITICAL        = 0x1,
> >  	BKOPS_STATUS_PERF_IMPACT         = 0x2,
> >  	BKOPS_STATUS_CRITICAL            = 0x3,
> > +	BKOPS_STATUS_MAX		 = BKOPS_STATUS_CRITICAL,
> >  };
> >
> >  /* UTP QUERY Transaction Specific Fields OpCode */ @@ -291,6 +305,14
> @@
> > enum {
> >  	UPIU_TASK_MANAGEMENT_FUNC_FAILED	= 0x05,
> >  	UPIU_INCORRECT_LOGICAL_UNIT_NO		= 0x09,
> >  };
> > +
> > +/* UFS device power modes */
> > +enum ufs_dev_pwr_mode {
> > +	UFS_ACTIVE_PWR_MODE	= 1,
> > +	UFS_SLEEP_PWR_MODE	= 2,
> > +	UFS_POWERDOWN_PWR_MODE	= 3,
> > +};
> > +
> >  /**
> >   * struct utp_upiu_header - UPIU header structure
> >   * @dword_0: UPIU header DW-0
> > @@ -437,6 +459,12 @@ struct ufs_query_res {
> >  #define UFS_VREG_VCCQ2_MIN_UV	   1650000 /* uV */
> >  #define UFS_VREG_VCCQ2_MAX_UV	   1950000 /* uV */
> >
> > +/*
> > + * VCCQ & VCCQ2 current requirement when UFS device is in sleep state
> > + * and link is in Hibern8 state.
> > + */
> > +#define UFS_VREG_LPM_LOAD_UA	1000 /* uA */
> > +
> >  struct ufs_vreg {
> >  	struct regulator *reg;
> >  	const char *name;
> > @@ -453,4 +481,10 @@ struct ufs_vreg_info {
> >  	struct ufs_vreg *vccq2;
> >  };
> >
> > +struct ufs_dev_info {
> > +	bool f_power_on_wp_en;
> > +	/* Keeps information if any of the LU is power on write protected */
> > +	bool is_lu_power_on_wp;
> > +};
> > +
> >  #endif /* End of Header */
> > diff --git a/drivers/scsi/ufs/ufshcd-pci.c b/drivers/scsi/ufs/ufshcd-pci.c index
> > 1aac2ef..b8f7774 100644
> > --- a/drivers/scsi/ufs/ufshcd-pci.c
> > +++ b/drivers/scsi/ufs/ufshcd-pci.c
> > @@ -43,34 +43,24 @@
> >   * @pdev: pointer to PCI device handle
> >   * @state: power state
> >   *
> > - * Returns -ENOSYS
> > + * Returns 0 if successful
> > + * Returns non-zero otherwise
> >   */
> >  static int ufshcd_pci_suspend(struct device *dev)  {
> > -	/*
> > -	 * TODO:
> > -	 * 1. Call ufshcd_suspend
> > -	 * 2. Do bus specific power management
> > -	 */
> > -
> > -	return -ENOSYS;
> > +	return ufshcd_system_suspend(dev_get_drvdata(dev));
> >  }
> >
> >  /**
> >   * ufshcd_pci_resume - resume power management function
> >   * @pdev: pointer to PCI device handle
> >   *
> > - * Returns -ENOSYS
> > + * Returns 0 if successful
> > + * Returns non-zero otherwise
> >   */
> >  static int ufshcd_pci_resume(struct device *dev)  {
> > -	/*
> > -	 * TODO:
> > -	 * 1. Call ufshcd_resume.
> > -	 * 2. Do bus specific wake up
> > -	 */
> > -
> > -	return -ENOSYS;
> > +	return ufshcd_system_resume(dev_get_drvdata(dev));
> >  }
> >  #else
> >  #define ufshcd_pci_suspend	NULL
> > @@ -80,30 +70,15 @@ static int ufshcd_pci_resume(struct device *dev)
> > #ifdef CONFIG_PM_RUNTIME  static int
> ufshcd_pci_runtime_suspend(struct
> > device *dev)  {
> > -	struct ufs_hba *hba = dev_get_drvdata(dev);
> > -
> > -	if (!hba)
> > -		return 0;
> > -
> > -	return ufshcd_runtime_suspend(hba);
> > +	return ufshcd_runtime_suspend(dev_get_drvdata(dev));
> >  }
> >  static int ufshcd_pci_runtime_resume(struct device *dev)  {
> > -	struct ufs_hba *hba = dev_get_drvdata(dev);
> > -
> > -	if (!hba)
> > -		return 0;
> > -
> > -	return ufshcd_runtime_resume(hba);
> > +	return ufshcd_runtime_resume(dev_get_drvdata(dev));
> >  }
> >  static int ufshcd_pci_runtime_idle(struct device *dev)  {
> > -	struct ufs_hba *hba = dev_get_drvdata(dev);
> > -
> > -	if (!hba)
> > -		return 0;
> > -
> > -	return ufshcd_runtime_idle(hba);
> > +	return ufshcd_runtime_idle(dev_get_drvdata(dev));
> >  }
> >  #else /* !CONFIG_PM_RUNTIME */
> >  #define ufshcd_pci_runtime_suspend	NULL
> > @@ -117,7 +92,7 @@ static int ufshcd_pci_runtime_idle(struct device *dev)
> >   */
> >  static void ufshcd_pci_shutdown(struct pci_dev *pdev)  {
> > -	ufshcd_hba_stop((struct ufs_hba *)pci_get_drvdata(pdev));
> > +	ufshcd_shutdown((struct ufs_hba *)pci_get_drvdata(pdev));
> >  }
> >
> >  /**
> > diff --git a/drivers/scsi/ufs/ufshcd-pltfrm.c b/drivers/scsi/ufs/ufshcd-pltfrm.c
> > index 642d80f..edaccd0 100644
> > --- a/drivers/scsi/ufs/ufshcd-pltfrm.c
> > +++ b/drivers/scsi/ufs/ufshcd-pltfrm.c
> > @@ -216,45 +216,24 @@ out:
> >   * ufshcd_pltfrm_suspend - suspend power management function
> >   * @dev: pointer to device handle
> >   *
> > - *
> > - * Returns 0
> > + * Returns 0 if successful
> > + * Returns non-zero otherwise
> >   */
> >  static int ufshcd_pltfrm_suspend(struct device *dev)  {
> > -	struct platform_device *pdev = to_platform_device(dev);
> > -	struct ufs_hba *hba =  platform_get_drvdata(pdev);
> > -
> > -	/*
> > -	 * TODO:
> > -	 * 1. Call ufshcd_suspend
> > -	 * 2. Do bus specific power management
> > -	 */
> > -
> > -	disable_irq(hba->irq);
> > -
> > -	return 0;
> > +	return ufshcd_system_suspend(dev_get_drvdata(dev));
> >  }
> >
> >  /**
> >   * ufshcd_pltfrm_resume - resume power management function
> >   * @dev: pointer to device handle
> >   *
> > - * Returns 0
> > + * Returns 0 if successful
> > + * Returns non-zero otherwise
> >   */
> >  static int ufshcd_pltfrm_resume(struct device *dev)  {
> > -	struct platform_device *pdev = to_platform_device(dev);
> > -	struct ufs_hba *hba =  platform_get_drvdata(pdev);
> > -
> > -	/*
> > -	 * TODO:
> > -	 * 1. Call ufshcd_resume.
> > -	 * 2. Do bus specific wake up
> > -	 */
> > -
> > -	enable_irq(hba->irq);
> > -
> > -	return 0;
> > +	return ufshcd_system_resume(dev_get_drvdata(dev));
> >  }
> >  #else
> >  #define ufshcd_pltfrm_suspend	NULL
> > @@ -264,30 +243,15 @@ static int ufshcd_pltfrm_resume(struct device
> *dev)
> > #ifdef CONFIG_PM_RUNTIME  static int
> > ufshcd_pltfrm_runtime_suspend(struct device *dev)  {
> > -	struct ufs_hba *hba =  dev_get_drvdata(dev);
> > -
> > -	if (!hba)
> > -		return 0;
> > -
> > -	return ufshcd_runtime_suspend(hba);
> > +	return ufshcd_runtime_suspend(dev_get_drvdata(dev));
> >  }
> >  static int ufshcd_pltfrm_runtime_resume(struct device *dev)  {
> > -	struct ufs_hba *hba =  dev_get_drvdata(dev);
> > -
> > -	if (!hba)
> > -		return 0;
> > -
> > -	return ufshcd_runtime_resume(hba);
> > +	return ufshcd_runtime_resume(dev_get_drvdata(dev));
> >  }
> >  static int ufshcd_pltfrm_runtime_idle(struct device *dev)  {
> > -	struct ufs_hba *hba =  dev_get_drvdata(dev);
> > -
> > -	if (!hba)
> > -		return 0;
> > -
> > -	return ufshcd_runtime_idle(hba);
> > +	return ufshcd_runtime_idle(dev_get_drvdata(dev));
> >  }
> >  #else /* !CONFIG_PM_RUNTIME */
> >  #define ufshcd_pltfrm_runtime_suspend	NULL
> > @@ -295,6 +259,11 @@ static int ufshcd_pltfrm_runtime_idle(struct device
> > *dev)
> >  #define ufshcd_pltfrm_runtime_idle	NULL
> >  #endif /* CONFIG_PM_RUNTIME */
> >
> > +static void ufshcd_pltfrm_shutdown(struct platform_device *pdev) {
> > +	ufshcd_shutdown((struct ufs_hba *)platform_get_drvdata(pdev)); }
> > +
> >  /**
> >   * ufshcd_pltfrm_probe - probe routine of the driver
> >   * @pdev: pointer to Platform device handle @@ -395,6 +364,7 @@ static
> > const struct dev_pm_ops ufshcd_dev_pm_ops = {  static struct
> > platform_driver ufshcd_pltfrm_driver = {
> >  	.probe	= ufshcd_pltfrm_probe,
> >  	.remove	= ufshcd_pltfrm_remove,
> > +	.shutdown = ufshcd_pltfrm_shutdown,
> >  	.driver	= {
> >  		.name	= "ufshcd",
> >  		.owner	= THIS_MODULE,
> > diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index
> > 876d210..fac71c9 100644
> > --- a/drivers/scsi/ufs/ufshcd.c
> > +++ b/drivers/scsi/ufs/ufshcd.c
> > @@ -44,7 +44,6 @@
> >
> >  #define UFSHCD_ENABLE_INTRS	(UTP_TRANSFER_REQ_COMPL |\
> >  				 UTP_TASK_REQ_COMPL |\
> > -				 UIC_POWER_MODE |\
> >  				 UFSHCD_ERROR_MASK)
> >  /* UIC command timeout, unit: ms */
> >  #define UIC_CMD_TIMEOUT	500
> > @@ -138,12 +137,63 @@ enum {
> >  #define ufshcd_clear_eh_in_progress(h) \
> >  	(h->eh_flags &= ~UFSHCD_EH_IN_PROGRESS)
> >
> > +#define ufshcd_set_ufs_dev_active(h) \
> > +	((h)->curr_dev_pwr_mode = UFS_ACTIVE_PWR_MODE) #define
> > +ufshcd_set_ufs_dev_sleep(h) \
> > +	((h)->curr_dev_pwr_mode = UFS_SLEEP_PWR_MODE) #define
> > +ufshcd_set_ufs_dev_poweroff(h) \
> > +	((h)->curr_dev_pwr_mode = UFS_POWERDOWN_PWR_MODE) #define
> > +ufshcd_is_ufs_dev_active(h) \
> > +	((h)->curr_dev_pwr_mode == UFS_ACTIVE_PWR_MODE) #define
> > +ufshcd_is_ufs_dev_sleep(h) \
> > +	((h)->curr_dev_pwr_mode == UFS_SLEEP_PWR_MODE) #define
> > +ufshcd_is_ufs_dev_poweroff(h) \
> > +	((h)->curr_dev_pwr_mode == UFS_POWERDOWN_PWR_MODE)
> > +
> > +static struct ufs_pm_lvl_states ufs_pm_lvl_states[] = {
> > +	{UFS_ACTIVE_PWR_MODE, UIC_LINK_ACTIVE_STATE},
> > +	{UFS_ACTIVE_PWR_MODE, UIC_LINK_HIBERN8_STATE},
> > +	{UFS_SLEEP_PWR_MODE, UIC_LINK_ACTIVE_STATE},
> > +	{UFS_SLEEP_PWR_MODE, UIC_LINK_HIBERN8_STATE},
> > +	{UFS_POWERDOWN_PWR_MODE, UIC_LINK_HIBERN8_STATE},
> > +	{UFS_POWERDOWN_PWR_MODE, UIC_LINK_OFF_STATE}, };
> > +
> > +static inline enum ufs_dev_pwr_mode
> > +ufs_get_pm_lvl_to_dev_pwr_mode(enum ufs_pm_level lvl) {
> > +	return ufs_pm_lvl_states[lvl].dev_state; }
> > +
> > +static inline enum uic_link_state
> > +ufs_get_pm_lvl_to_link_pwr_state(enum ufs_pm_level lvl) {
> > +	return ufs_pm_lvl_states[lvl].link_state;
> > +}
> > +
> >  static void ufshcd_tmc_handler(struct ufs_hba *hba);  static void
> > ufshcd_async_scan(void *data, async_cookie_t cookie);  static int
> > ufshcd_reset_and_restore(struct ufs_hba *hba);  static int
> > ufshcd_clear_tm_cmd(struct ufs_hba *hba, int tag);  static void
> > ufshcd_hba_exit(struct ufs_hba *hba);  static int ufshcd_probe_hba(struct
> > ufs_hba *hba);
> > +static int ufshcd_host_reset_and_restore(struct ufs_hba *hba);
> > +
> > +static inline void ufshcd_enable_irq(struct ufs_hba *hba) {
> > +	if (!hba->is_irq_enabled) {
> > +		enable_irq(hba->irq);
> > +		hba->is_irq_enabled = true;
> > +	}
> > +}
> > +
> > +static inline void ufshcd_disable_irq(struct ufs_hba *hba) {
> > +	if (hba->is_irq_enabled) {
> > +		disable_irq(hba->irq);
> > +		hba->is_irq_enabled = false;
> > +	}
> > +}
> >
> >  /*
> >   * ufshcd_wait_for_register - wait for register value to change @@
> -1778,44
> > +1828,48 @@ out:
> >  EXPORT_SYMBOL_GPL(ufshcd_dme_get_attr);
> >
> >  /**
> > - * ufshcd_uic_change_pwr_mode - Perform the UIC power mode chage
> > - *				using DME_SET primitives.
> > + * ufshcd_uic_pwr_ctrl - executes UIC commands (which affects the link
> > + power
> > + * state) and waits for it to take effect.
> > + *
> >   * @hba: per adapter instance
> > - * @mode: powr mode value
> > + * @cmd: UIC command to execute
> > + *
> > + * DME operations like DME_SET(PA_PWRMODE), DME_HIBERNATE_ENTER
> > &
> > + * DME_HIBERNATE_EXIT commands take some time to take its effect on
> > + both host
> > + * and device UniPro link and hence it's final completion would be
> > + indicated by
> > + * dedicated status bits in Interrupt Status register (UPMS, UHES,
> > + UHXS) in
> > + * addition to normal UIC command completion Status (UCCS). This
> > + function only
> > + * returns after the relevant status bits indicate the completion.
> >   *
> >   * Returns 0 on success, non-zero value on failure
> >   */
> > -static int ufshcd_uic_change_pwr_mode(struct ufs_hba *hba, u8 mode)
> > +int ufshcd_uic_pwr_ctrl(struct ufs_hba *hba, struct uic_command *cmd)
> >  {
> > -	struct uic_command uic_cmd = {0};
> > -	struct completion pwr_done;
> > +	struct completion uic_async_done;
> >  	unsigned long flags;
> >  	u8 status;
> >  	int ret;
> >
> > -	uic_cmd.command = UIC_CMD_DME_SET;
> > -	uic_cmd.argument1 = UIC_ARG_MIB(PA_PWRMODE);
> > -	uic_cmd.argument3 = mode;
> > -	init_completion(&pwr_done);
> > -
> >  	mutex_lock(&hba->uic_cmd_mutex);
> > +	init_completion(&uic_async_done);
> >
> >  	spin_lock_irqsave(hba->host->host_lock, flags);
> > -	hba->pwr_done = &pwr_done;
> > +	hba->uic_async_done = &uic_async_done;
> >  	spin_unlock_irqrestore(hba->host->host_lock, flags);
> > -	ret = __ufshcd_send_uic_cmd(hba, &uic_cmd);
> > +
> > +	ret = __ufshcd_send_uic_cmd(hba, cmd);
> >  	if (ret) {
> >  		dev_err(hba->dev,
> > -			"pwr mode change with mode 0x%x uic error %d\n",
> > -			mode, ret);
> > +			"pwr ctrl cmd 0x%x with mode 0x%x uic error %d\n",
> > +			cmd->command, cmd->argument3, ret);
> >  		goto out;
> >  	}
> >
> > -	if (!wait_for_completion_timeout(hba->pwr_done,
> > +	if (!wait_for_completion_timeout(hba->uic_async_done,
> >  					 msecs_to_jiffies(UIC_CMD_TIMEOUT))) {
> >  		dev_err(hba->dev,
> > -			"pwr mode change with mode 0x%x completion timeout\n",
> > -			mode);
> > +			"pwr ctrl cmd 0x%x with mode 0x%x completion timeout\n",
> > +			cmd->command, cmd->argument3);
> >  		ret = -ETIMEDOUT;
> >  		goto out;
> >  	}
> > @@ -1823,19 +1877,62 @@ static int ufshcd_uic_change_pwr_mode(struct
> > ufs_hba *hba, u8 mode)
> >  	status = ufshcd_get_upmcrs(hba);
> >  	if (status != PWR_LOCAL) {
> >  		dev_err(hba->dev,
> > -			"pwr mode change failed, host umpcrs:0x%x\n",
> > -			status);
> > +			"pwr ctrl cmd 0x%0x failed, host umpcrs:0x%x\n",
> > +			cmd->command, status);
> >  		ret = (status != PWR_OK) ? status : -1;
> >  	}
> >  out:
> >  	spin_lock_irqsave(hba->host->host_lock, flags);
> > -	hba->pwr_done = NULL;
> > +	hba->uic_async_done = NULL;
> >  	spin_unlock_irqrestore(hba->host->host_lock, flags);
> >  	mutex_unlock(&hba->uic_cmd_mutex);
> >  	return ret;
> >  }
> >
> >  /**
> > + * ufshcd_uic_change_pwr_mode - Perform the UIC power mode chage
> > + *				using DME_SET primitives.
> > + * @hba: per adapter instance
> > + * @mode: powr mode value
> > + *
> > + * Returns 0 on success, non-zero value on failure  */ static int
> > +ufshcd_uic_change_pwr_mode(struct ufs_hba *hba, u8 mode) {
> > +	struct uic_command uic_cmd = {0};
> > +
> > +	uic_cmd.command = UIC_CMD_DME_SET;
> > +	uic_cmd.argument1 = UIC_ARG_MIB(PA_PWRMODE);
> > +	uic_cmd.argument3 = mode;
> > +
> > +	return ufshcd_uic_pwr_ctrl(hba, &uic_cmd); }
> > +
> > +static int ufshcd_uic_hibern8_enter(struct ufs_hba *hba) {
> > +	struct uic_command uic_cmd = {0};
> > +
> > +	uic_cmd.command = UIC_CMD_DME_HIBER_ENTER;
> > +
> > +	return ufshcd_uic_pwr_ctrl(hba, &uic_cmd); }
> > +
> > +static int ufshcd_uic_hibern8_exit(struct ufs_hba *hba) {
> > +	struct uic_command uic_cmd = {0};
> > +	int ret;
> > +
> > +	uic_cmd.command = UIC_CMD_DME_HIBER_EXIT;
> > +	ret = ufshcd_uic_pwr_ctrl(hba, &uic_cmd);
> > +	if (ret) {
> > +		ufshcd_set_link_off(hba);
> > +		ret = ufshcd_host_reset_and_restore(hba);
> > +	}
> > +
> > +	return ret;
> > +}
> > +
> > +/**
> >   * ufshcd_config_max_pwr_mode - Set & Change power mode with
> >   *	maximum capability attribute information.
> >   * @hba: per adapter instance
> > @@ -2034,6 +2131,9 @@ static int ufshcd_hba_enable(struct ufs_hba *hba)
> >  		msleep(5);
> >  	}
> >
> > +	/* UniPro link is disabled at this point */
> > +	ufshcd_set_link_off(hba);
> > +
> >  	if (hba->vops && hba->vops->hce_enable_notify)
> >  		hba->vops->hce_enable_notify(hba, PRE_CHANGE);
> >
> > @@ -2066,7 +2166,7 @@ static int ufshcd_hba_enable(struct ufs_hba *hba)
> >  	}
> >
> >  	/* enable UIC related interrupts */
> > -	ufshcd_enable_intr(hba, UIC_COMMAND_COMPL);
> > +	ufshcd_enable_intr(hba, UFSHCD_UIC_MASK);
> >
> >  	if (hba->vops && hba->vops->hce_enable_notify)
> >  		hba->vops->hce_enable_notify(hba, POST_CHANGE); @@ -2195,6
> > +2295,62 @@ static void ufshcd_set_queue_depth(struct scsi_device *sdev)
> >  	scsi_activate_tcq(sdev, lun_qdepth);
> >  }
> >
> > +/*
> > + * ufshcd_get_lu_wp - returns the "b_lu_write_protect" from UNIT
> > +DESCRIPTOR
> > + * @hba: per-adapter instance
> > + * @lun: UFS device lun id
> > + * @b_lu_write_protect: pointer to buffer to hold the LU's write
> > +protect info
> > + *
> > + * Returns 0 in case of success and b_lu_write_protect status would be
> > +returned
> > + * @b_lu_write_protect parameter.
> > + * Returns -ENOTSUPP if reading b_lu_write_protect is not supported.
> > + * Returns -EINVAL in case of invalid parameters passed to this function.
> > + */
> > +static int ufshcd_get_lu_wp(struct ufs_hba *hba,
> > +			    u8 lun,
> > +			    u8 *b_lu_write_protect)
> > +{
> > +	int ret;
> > +
> > +	if (!b_lu_write_protect)
> > +		ret = -EINVAL;
> > +	/*
> > +	 * According to UFS device spec, RPMB LU can't be write
> > +	 * protected so skip reading bLUWriteProtect parameter for
> > +	 * it. For other W-LUs, UNIT DESCRIPTOR is not available.
> > +	 */
> > +	else if (lun >= UFS_UPIU_MAX_GENERAL_LUN)
> > +		ret = -ENOTSUPP;
> > +	else
> > +		ret = ufshcd_read_unit_desc_param(hba,
> > +					  lun,
> > +					  UNIT_DESC_PARAM_LU_WR_PROTECT,
> > +					  b_lu_write_protect,
> > +					  sizeof(*b_lu_write_protect));
> > +	return ret;
> > +}
> > +
> > +/**
> > + * ufshcd_get_lu_power_on_wp_status - get LU's power on write protect
> > + * status
> > + * @hba: per-adapter instance
> > + * @sdev: pointer to SCSI device
> > + *
> > + */
> > +static inline void ufshcd_get_lu_power_on_wp_status(struct ufs_hba *hba,
> > +						    struct scsi_device *sdev)
> > +{
> > +	if (hba->dev_info.f_power_on_wp_en &&
> > +	    !hba->dev_info.is_lu_power_on_wp) {
> > +		u8 b_lu_write_protect;
> > +
> > +		if (!ufshcd_get_lu_wp(hba, ufshcd_scsi_to_upiu_lun(sdev->lun),
> > +				      &b_lu_write_protect) &&
> > +		    (b_lu_write_protect == UFS_LU_POWER_ON_WP))
> > +			hba->dev_info.is_lu_power_on_wp = true;
> > +	}
> > +}
> > +
> >  /**
> >   * ufshcd_slave_alloc - handle initial SCSI device configurations
> >   * @sdev: pointer to SCSI device
> > @@ -2221,6 +2377,21 @@ static int ufshcd_slave_alloc(struct scsi_device
> > *sdev)
> >
> >  	ufshcd_set_queue_depth(sdev);
> >
> > +	ufshcd_get_lu_power_on_wp_status(hba, sdev);
> > +
> > +	/*
> > +	 * For selecting the UFS device power mode (Active / UFS_Sleep /
> > +	 * UFS_PowerDown), SCSI power management command (START STOP
> > UNIT)
> > +	 * needs to be sent to a "UFS device" Well known Logical Unit (W-LU).
> > +	 * As this command would be sent during the UFS host controller
> > +	 * runtime/system PM callbacks, we need a reference to "scsi_device"
> > +	 * associated to "UFS device" W-LU. This change saves the "scsi_device"
> > +	 * reference for "UFS device" W-LU during slave_configure() callback
> > +	 * from SCSI mid layer.
> > +	 */
> > +	if (ufshcd_scsi_to_upiu_lun(sdev->lun) == UFS_UPIU_UFS_DEVICE_WLUN)
> > +		hba->sdev_ufs_device = sdev;
> > +
> >  	return 0;
> >  }
> >
> > @@ -2451,8 +2622,8 @@ static void ufshcd_uic_cmd_compl(struct ufs_hba
> > *hba, u32 intr_status)
> >  		complete(&hba->active_uic_cmd->done);
> >  	}
> >
> > -	if ((intr_status & UIC_POWER_MODE) && hba->pwr_done)
> > -		complete(hba->pwr_done);
> > +	if ((intr_status & UFSHCD_UIC_PWR_MASK) && hba->uic_async_done)
> > +		complete(hba->uic_async_done);
> >  }
> >
> >  /**
> > @@ -2664,33 +2835,62 @@ static inline int ufshcd_get_bkops_status(struct
> > ufs_hba *hba, u32 *status)  }
> >
> >  /**
> > - * ufshcd_urgent_bkops - handle urgent bkops exception event
> > + * ufshcd_bkops_ctrl - control the auto bkops based on current bkops
> > + status
> >   * @hba: per-adapter instance
> > + * @status: bkops_status value
> >   *
> > - * Enable fBackgroundOpsEn flag in the device to permit background
> > - * operations.
> > + * Read the bkops_status from the UFS device and Enable
> > + fBackgroundOpsEn
> > + * flag in the device to permit background operations if the device
> > + * bkops_status is greater than or equal to "status" argument passed to
> > + * this function, disable otherwise.
> > + *
> > + * Returns 0 for success, non-zero in case of failure.
> > + *
> > + * NOTE: Caller of this function can check the
> > + "hba->auto_bkops_enabled" flag
> > + * to know whether auto bkops is enabled or disabled after this
> > + function
> > + * returns control to it.
> >   */
> > -static int ufshcd_urgent_bkops(struct ufs_hba *hba)
> > +static int ufshcd_bkops_ctrl(struct ufs_hba *hba,
> > +			     enum bkops_status status)
> >  {
> >  	int err;
> > -	u32 status = 0;
> > +	u32 curr_status = 0;
> >
> > -	err = ufshcd_get_bkops_status(hba, &status);
> > +	err = ufshcd_get_bkops_status(hba, &curr_status);
> >  	if (err) {
> >  		dev_err(hba->dev, "%s: failed to get BKOPS status %d\n",
> >  				__func__, err);
> >  		goto out;
> > +	} else if (curr_status > BKOPS_STATUS_MAX) {
> > +		dev_err(hba->dev, "%s: invalid BKOPS status %d\n",
> > +				__func__, curr_status);
> > +		err = -EINVAL;
> > +		goto out;
> >  	}
> >
> > -	status = status & 0xF;
> > -
> > -	/* handle only if status indicates performance impact or critical */
> > -	if (status >= BKOPS_STATUS_PERF_IMPACT)
> > +	if (curr_status >= status)
> >  		err = ufshcd_enable_auto_bkops(hba);
> > +	else
> > +		err = ufshcd_disable_auto_bkops(hba);
> >  out:
> >  	return err;
> >  }
> >
> > +/**
> > + * ufshcd_urgent_bkops - handle urgent bkops exception event
> > + * @hba: per-adapter instance
> > + *
> > + * Enable fBackgroundOpsEn flag in the device to permit background
> > + * operations.
> > + *
> > + * If BKOPs is enabled, this function returns 0, 1 if the bkops in not
> > +enabled
> > + * and negative error value for any other failure.
> > + */
> > +static int ufshcd_urgent_bkops(struct ufs_hba *hba) {
> > +	return ufshcd_bkops_ctrl(hba, BKOPS_STATUS_PERF_IMPACT); }
> > +
> >  static inline int ufshcd_get_ee_status(struct ufs_hba *hba, u32 *status)  {
> >  	return ufshcd_query_attr(hba, UPIU_QUERY_OPCODE_READ_ATTR, @@
> > -2722,7 +2922,7 @@ static void ufshcd_exception_event_handler(struct
> > work_struct *work)
> >  	status &= hba->ee_ctrl_mask;
> >  	if (status & MASK_EE_URGENT_BKOPS) {
> >  		err = ufshcd_urgent_bkops(hba);
> > -		if (err)
> > +		if (err < 0)
> >  			dev_err(hba->dev, "%s: failed to handle urgent bkops %d\n",
> >  					__func__, err);
> >  	}
> > @@ -3441,7 +3641,8 @@ static int ufshcd_probe_hba(struct ufs_hba *hba)
> >  	if (ret)
> >  		goto out;
> >
> > -	ufshcd_config_max_pwr_mode(hba);
> > +	/* UniPro link is active now */
> > +	ufshcd_set_link_active(hba);
> >
> >  	ret = ufshcd_verify_dev_init(hba);
> >  	if (ret)
> > @@ -3451,14 +3652,29 @@ static int ufshcd_probe_hba(struct ufs_hba
> *hba)
> >  	if (ret)
> >  		goto out;
> >
> > +	/* UFS device is also active now */
> > +	ufshcd_set_ufs_dev_active(hba);
> >  	ufshcd_force_reset_auto_bkops(hba);
> >  	hba->ufshcd_state = UFSHCD_STATE_OPERATIONAL;
> > +	hba->wlun_dev_clr_ua = true;
> > +
> > +	ufshcd_config_max_pwr_mode(hba);
> > +
> > +	/*
> > +	 * If we are in error handling context or in power management callbacks
> > +	 * context, no need to scan the host
> > +	 */
> > +	if (!ufshcd_eh_in_progress(hba) && !hba->pm_op_in_progress) {
> > +		bool flag;
> > +
> > +		/* clear any previous UFS device information */
> > +		memset(&hba->dev_info, 0, sizeof(hba->dev_info));
> > +		if (!ufshcd_query_flag(hba, UPIU_QUERY_OPCODE_READ_FLAG,
> > +				       QUERY_FLAG_IDN_PWR_ON_WPE, &flag))
> > +			hba->dev_info.f_power_on_wp_en = flag;
> >
> > -	/* If we are in error handling context no need to scan the host */
> > -	if (!ufshcd_eh_in_progress(hba)) {
> >  		if (!hba->is_init_prefetch)
> >  			ufshcd_init_icc_levels(hba);
> > -
> >  		scsi_scan_host(hba->host);
> >  		pm_runtime_put_sync(hba->dev);
> >  	}
> > @@ -3471,8 +3687,10 @@ out:
> >  	 * If we failed to initialize the device or the device is not
> >  	 * present, turn off the power/clocks etc.
> >  	 */
> > -	if (ret && !ufshcd_eh_in_progress(hba))
> > +	if (ret && !ufshcd_eh_in_progress(hba) && !hba->pm_op_in_progress) {
> > +		pm_runtime_put_sync(hba->dev);
> >  		ufshcd_hba_exit(hba);
> > +	}
> >
> >  	return ret;
> >  }
> > @@ -3507,6 +3725,42 @@ static struct scsi_host_template
> > ufshcd_driver_template = {
> >  	.can_queue		= UFSHCD_CAN_QUEUE,
> >  };
> >
> > +static int ufshcd_config_vreg_load(struct device *dev, struct ufs_vreg *vreg,
> > +				   int ua)
> > +{
> > +	int ret = 0;
> > +	struct regulator *reg = vreg->reg;
> > +	const char *name = vreg->name;
> > +
> > +	BUG_ON(!vreg);
> 
> For the UFS host controller driver, which doesn't have the ufs_vreg structure for
> vcc and vccq, this function can cause kernel panic due to this BUG_ON(). Any
> reason to put a BUG_ON here instead of a NULL pointer checking?
> 
> Thanks
> Chuanxiao
> 
> > +
> > +	ret = regulator_set_optimum_mode(reg, ua);
> > +	if (ret >= 0) {
> > +		/*
> > +		 * regulator_set_optimum_mode() returns new regulator
> > +		 * mode upon success.
> > +		 */
> > +		ret = 0;
> > +	} else {
> > +		dev_err(dev, "%s: %s set optimum mode(ua=%d) failed, err=%d\n",
> > +				__func__, name, ua, ret);
> > +	}
> > +
> > +	return ret;
> > +}
> > +
> > +static inline int ufshcd_config_vreg_lpm(struct ufs_hba *hba,
> > +					 struct ufs_vreg *vreg)
> > +{
> > +	return ufshcd_config_vreg_load(hba->dev, vreg,
> > UFS_VREG_LPM_LOAD_UA);
> > +}
> > +
> > +static inline int ufshcd_config_vreg_hpm(struct ufs_hba *hba,
> > +					 struct ufs_vreg *vreg)
> > +{
> > +	return ufshcd_config_vreg_load(hba->dev, vreg, vreg->max_uA); }
> > +
> >  static int ufshcd_config_vreg(struct device *dev,
> >  		struct ufs_vreg *vreg, bool on)
> >  {
> > @@ -3527,18 +3781,9 @@ static int ufshcd_config_vreg(struct device *dev,
> >  		}
> >
> >  		uA_load = on ? vreg->max_uA : 0;
> > -		ret = regulator_set_optimum_mode(reg, uA_load);
> > -		if (ret >= 0) {
> > -			/*
> > -			 * regulator_set_optimum_mode() returns new regulator
> > -			 * mode upon success.
> > -			 */
> > -			ret = 0;
> > -		} else {
> > -			dev_err(dev, "%s: %s set optimum mode(uA_load=%d) failed,
> > err=%d\n",
> > -					__func__, name, uA_load, ret);
> > +		ret = ufshcd_config_vreg_load(dev, vreg, uA_load);
> > +		if (ret)
> >  			goto out;
> > -		}
> >  	}
> >  out:
> >  	return ret;
> > @@ -3654,7 +3899,8 @@ out:
> >  	return ret;
> >  }
> >
> > -static int ufshcd_setup_clocks(struct ufs_hba *hba, bool on)
> > +static int __ufshcd_setup_clocks(struct ufs_hba *hba, bool on,
> > +				 bool skip_ref_clk)
> >  {
> >  	int ret = 0;
> >  	struct ufs_clk_info *clki;
> > @@ -3665,6 +3911,9 @@ static int ufshcd_setup_clocks(struct ufs_hba
> *hba,
> > bool on)
> >
> >  	list_for_each_entry(clki, head, list) {
> >  		if (!IS_ERR_OR_NULL(clki->clk)) {
> > +			if (skip_ref_clk && !strcmp(clki->name, "ref_clk"))
> > +				continue;
> > +
> >  			if (on && !clki->enabled) {
> >  				ret = clk_prepare_enable(clki->clk);
> >  				if (ret) {
> > @@ -3690,6 +3939,11 @@ out:
> >  	return ret;
> >  }
> >
> > +static int ufshcd_setup_clocks(struct ufs_hba *hba, bool on) {
> > +	return  __ufshcd_setup_clocks(hba, on, false); }
> > +
> >  static int ufshcd_init_clocks(struct ufs_hba *hba)  {
> >  	int ret = 0;
> > @@ -3828,68 +4082,514 @@ static void ufshcd_hba_exit(struct ufs_hba
> *hba)
> >  	}
> >  }
> >
> > +static int
> > +ufshcd_send_request_sense(struct ufs_hba *hba, struct scsi_device *sdp)
> > +{
> > +	unsigned char cmd[6] = {REQUEST_SENSE,
> > +				0,
> > +				0,
> > +				0,
> > +				SCSI_SENSE_BUFFERSIZE,
> > +				0};
> > +	char *buffer;
> > +	int ret;
> > +
> > +	buffer = kzalloc(SCSI_SENSE_BUFFERSIZE, GFP_KERNEL);
> > +	if (!buffer) {
> > +		ret = -ENOMEM;
> > +		goto out;
> > +	}
> > +
> > +	ret = scsi_execute_req_flags(sdp, cmd, DMA_FROM_DEVICE, buffer,
> > +				SCSI_SENSE_BUFFERSIZE, NULL,
> > +				msecs_to_jiffies(1000), 3, NULL, REQ_PM);
> > +	if (ret)
> > +		pr_err("%s: failed with err %d\n", __func__, ret);
> > +
> > +	kfree(buffer);
> > +out:
> > +	return ret;
> > +}
> > +
> >  /**
> > - * ufshcd_suspend - suspend power management function
> > + * ufshcd_set_dev_pwr_mode - sends START STOP UNIT command to set
> > device
> > + *			     power mode
> >   * @hba: per adapter instance
> > - * @state: power state
> > + * @pwr_mode: device power mode to set
> >   *
> > - * Returns -ENOSYS
> > + * Returns 0 if requested power mode is set successfully
> > + * Returns non-zero if failed to set the requested power mode
> >   */
> > -int ufshcd_suspend(struct ufs_hba *hba, pm_message_t state)
> > +static int ufshcd_set_dev_pwr_mode(struct ufs_hba *hba,
> > +				     enum ufs_dev_pwr_mode pwr_mode)
> >  {
> > +	unsigned char cmd[6] = { START_STOP };
> > +	struct scsi_sense_hdr sshdr;
> > +	struct scsi_device *sdp = hba->sdev_ufs_device;
> > +	int ret;
> > +
> > +	if (!sdp || !scsi_device_online(sdp))
> > +		return -ENODEV;
> > +
> > +	/*
> > +	 * If scsi commands fail, the scsi mid-layer schedules scsi error-
> > +	 * handling, which would wait for host to be resumed. Since we know
> > +	 * we are functional while we are here, skip host resume in error
> > +	 * handling context.
> > +	 */
> > +	hba->host->eh_noresume = 1;
> > +	if (hba->wlun_dev_clr_ua) {
> > +		ret = ufshcd_send_request_sense(hba, sdp);
> > +		if (ret)
> > +			goto out;
> > +		/* Unit attention condition is cleared now */
> > +		hba->wlun_dev_clr_ua = false;
> > +	}
> > +
> > +	cmd[4] = pwr_mode << 4;
> > +
> >  	/*
> > -	 * TODO:
> > -	 * 1. Block SCSI requests from SCSI midlayer
> > -	 * 2. Change the internal driver state to non operational
> > -	 * 3. Set UTRLRSR and UTMRLRSR bits to zero
> > -	 * 4. Wait until outstanding commands are completed
> > -	 * 5. Set HCE to zero to send the UFS host controller to reset state
> > +	 * Current function would be generally called from the power
> > management
> > +	 * callbacks hence set the REQ_PM flag so that it doesn't resume the
> > +	 * already suspended childs.
> >  	 */
> > +	ret = scsi_execute_req_flags(sdp, cmd, DMA_NONE, NULL, 0, &sshdr,
> > +				     START_STOP_TIMEOUT, 0, NULL, REQ_PM);
> > +	if (ret) {
> > +		sdev_printk(KERN_WARNING, sdp,
> > +			  "START_STOP failed for power mode: %d\n", pwr_mode);
> > +		scsi_show_result(ret);
> > +		if (driver_byte(ret) & DRIVER_SENSE) {
> > +			scsi_show_sense_hdr(&sshdr);
> > +			scsi_show_extd_sense(sshdr.asc, sshdr.ascq);
> > +		}
> > +	}
> >
> > -	return -ENOSYS;
> > +	if (!ret)
> > +		hba->curr_dev_pwr_mode = pwr_mode;
> > +out:
> > +	hba->host->eh_noresume = 0;
> > +	return ret;
> > +}
> > +
> > +static int ufshcd_link_state_transition(struct ufs_hba *hba,
> > +					enum uic_link_state req_link_state,
> > +					int check_for_bkops)
> > +{
> > +	int ret = 0;
> > +
> > +	if (req_link_state == hba->uic_link_state)
> > +		return 0;
> > +
> > +	if (req_link_state == UIC_LINK_HIBERN8_STATE) {
> > +		ret = ufshcd_uic_hibern8_enter(hba);
> > +		if (!ret)
> > +			ufshcd_set_link_hibern8(hba);
> > +		else
> > +			goto out;
> > +	}
> > +	/*
> > +	 * If autobkops is enabled, link can't be turned off because
> > +	 * turning off the link would also turn off the device.
> > +	 */
> > +	else if ((req_link_state == UIC_LINK_OFF_STATE) &&
> > +		   (!check_for_bkops || (check_for_bkops &&
> > +		    !hba->auto_bkops_enabled))) {
> > +		/*
> > +		 * Change controller state to "reset state" which
> > +		 * should also put the link in off/reset state
> > +		 */
> > +		ufshcd_hba_stop(hba);
> > +		/*
> > +		 * TODO: Check if we need any delay to make sure that
> > +		 * controller is reset
> > +		 */
> > +		ufshcd_set_link_off(hba);
> > +	}
> > +
> > +out:
> > +	return ret;
> > +}
> > +
> > +static void ufshcd_vreg_set_lpm(struct ufs_hba *hba) {
> > +	/*
> > +	 * If UFS device is either in UFS_Sleep turn off VCC rail to save some
> > +	 * power.
> > +	 *
> > +	 * If UFS device and link is in OFF state, all power supplies (VCC,
> > +	 * VCCQ, VCCQ2) can be turned off if power on write protect is not
> > +	 * required. If UFS link is inactive (Hibern8 or OFF state) and device
> > +	 * is in sleep state, put VCCQ & VCCQ2 rails in LPM mode.
> > +	 *
> > +	 * Ignore the error returned by ufshcd_toggle_vreg() as device is anyway
> > +	 * in low power state which would save some power.
> > +	 */
> > +	if (ufshcd_is_ufs_dev_poweroff(hba) && ufshcd_is_link_off(hba) &&
> > +	    !hba->dev_info.is_lu_power_on_wp) {
> > +		ufshcd_setup_vreg(hba, false);
> > +	} else if (!ufshcd_is_ufs_dev_active(hba)) {
> > +		ufshcd_toggle_vreg(hba->dev, hba->vreg_info.vcc, false);
> > +		if (!ufshcd_is_link_active(hba)) {
> > +			ufshcd_config_vreg_lpm(hba, hba->vreg_info.vccq);
> > +			ufshcd_config_vreg_lpm(hba, hba->vreg_info.vccq2);
> > +		}
> > +	}
> > +}
> > +
> > +static int ufshcd_vreg_set_hpm(struct ufs_hba *hba) {
> > +	int ret = 0;
> > +
> > +	if (ufshcd_is_ufs_dev_poweroff(hba) && ufshcd_is_link_off(hba) &&
> > +	    !hba->dev_info.is_lu_power_on_wp) {
> > +		ret = ufshcd_setup_vreg(hba, true);
> > +	} else if (!ufshcd_is_ufs_dev_active(hba)) {
> > +		ret = ufshcd_toggle_vreg(hba->dev, hba->vreg_info.vcc, true);
> > +		if (!ret && !ufshcd_is_link_active(hba)) {
> > +			ret = ufshcd_config_vreg_hpm(hba, hba->vreg_info.vccq);
> > +			if (ret)
> > +				goto vcc_disable;
> > +			ret = ufshcd_config_vreg_hpm(hba, hba->vreg_info.vccq2);
> > +			if (ret)
> > +				goto vccq_lpm;
> > +		}
> > +	}
> > +	goto out;
> > +
> > +vccq_lpm:
> > +	ufshcd_config_vreg_lpm(hba, hba->vreg_info.vccq);
> > +vcc_disable:
> > +	ufshcd_toggle_vreg(hba->dev, hba->vreg_info.vcc, false);
> > +out:
> > +	return ret;
> >  }
> > -EXPORT_SYMBOL_GPL(ufshcd_suspend);
> >
> >  /**
> > - * ufshcd_resume - resume power management function
> > + * ufshcd_suspend - helper function for suspend operations
> >   * @hba: per adapter instance
> > + * @pm_op: desired low power operation type
> >   *
> > - * Returns -ENOSYS
> > + * This function will try to put the UFS device and link into low power
> > + * mode based on the "rpm_lvl" (Runtime PM level) or "spm_lvl"
> > + * (System PM level).
> > + *
> > + * If this function is called during shutdown, it will make sure that
> > + * both UFS device and UFS link is powered off.
> > + *
> > + * NOTE: UFS device & link must be active before we enter in this function.
> > + *
> > + * Returns 0 for success and non-zero for failure
> >   */
> > -int ufshcd_resume(struct ufs_hba *hba)
> > +static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
> >  {
> > +	int ret = 0;
> > +	enum ufs_pm_level pm_lvl;
> > +	enum ufs_dev_pwr_mode req_dev_pwr_mode;
> > +	enum uic_link_state req_link_state;
> > +
> > +	hba->pm_op_in_progress = 1;
> > +	if (!ufshcd_is_shutdown_pm(pm_op)) {
> > +		pm_lvl = ufshcd_is_runtime_pm(pm_op) ?
> > +			 hba->rpm_lvl : hba->spm_lvl;
> > +		req_dev_pwr_mode = ufs_get_pm_lvl_to_dev_pwr_mode(pm_lvl);
> > +		req_link_state = ufs_get_pm_lvl_to_link_pwr_state(pm_lvl);
> > +	} else {
> > +		req_dev_pwr_mode = UFS_POWERDOWN_PWR_MODE;
> > +		req_link_state = UIC_LINK_OFF_STATE;
> > +	}
> > +
> > +	/*
> > +	 * If we can't transition into any of the low power modes
> > +	 * just gate the clocks.
> > +	 */
> > +	if (req_dev_pwr_mode == UFS_ACTIVE_PWR_MODE &&
> > +			req_link_state == UIC_LINK_ACTIVE_STATE) {
> > +		goto disable_clks;
> > +	}
> > +
> > +	if ((req_dev_pwr_mode == hba->curr_dev_pwr_mode) &&
> > +	    (req_link_state == hba->uic_link_state))
> > +		goto out;
> > +
> > +	/* UFS device & link must be active before we enter in this function */
> > +	if (!ufshcd_is_ufs_dev_active(hba) || !ufshcd_is_link_active(hba)) {
> > +		ret = -EINVAL;
> > +		goto out;
> > +	}
> > +
> > +	if (ufshcd_is_runtime_pm(pm_op)) {
> > +		/*
> > +		 * The device is idle with no requests in the queue,
> > +		 * allow background operations if needed.
> > +		 */
> > +		ret = ufshcd_bkops_ctrl(hba, BKOPS_STATUS_NON_CRITICAL);
> > +		if (ret)
> > +			goto out;
> > +	}
> > +
> > +	if ((req_dev_pwr_mode != hba->curr_dev_pwr_mode) &&
> > +	     ((ufshcd_is_runtime_pm(pm_op) && !hba->auto_bkops_enabled) ||
> > +	       !ufshcd_is_runtime_pm(pm_op))) {
> > +		/* ensure that bkops is disabled */
> > +		ufshcd_disable_auto_bkops(hba);
> > +		ret = ufshcd_set_dev_pwr_mode(hba, req_dev_pwr_mode);
> > +		if (ret)
> > +			goto out;
> > +	}
> > +
> > +	ret = ufshcd_link_state_transition(hba, req_link_state, 1);
> > +	if (ret)
> > +		goto set_dev_active;
> > +
> > +	ufshcd_vreg_set_lpm(hba);
> > +
> > +disable_clks:
> > +	/*
> > +	 * Call vendor specific suspend callback. As these callbacks may access
> > +	 * vendor specific host controller register space call them before the
> > +	 * host clocks are ON.
> > +	 */
> > +	if (hba->vops && hba->vops->suspend) {
> > +		ret = hba->vops->suspend(hba, pm_op);
> > +		if (ret)
> > +			goto set_link_active;
> > +	}
> > +
> > +	if (hba->vops && hba->vops->setup_clocks) {
> > +		ret = hba->vops->setup_clocks(hba, false);
> > +		if (ret)
> > +			goto vops_resume;
> > +	}
> > +
> > +	if (!ufshcd_is_link_active(hba))
> > +		ufshcd_setup_clocks(hba, false);
> > +	else
> > +		/* If link is active, device ref_clk can't be switched off */
> > +		__ufshcd_setup_clocks(hba, false, true);
> > +
> >  	/*
> > -	 * TODO:
> > -	 * 1. Set HCE to 1, to start the UFS host controller
> > -	 * initialization process
> > -	 * 2. Set UTRLRSR and UTMRLRSR bits to 1
> > -	 * 3. Change the internal driver state to operational
> > -	 * 4. Unblock SCSI requests from SCSI midlayer
> > +	 * Disable the host irq as host controller as there won't be any
> > +	 * host controller trasanction expected till resume.
> >  	 */
> > +	ufshcd_disable_irq(hba);
> > +	goto out;
> >
> > -	return -ENOSYS;
> > +vops_resume:
> > +	if (hba->vops && hba->vops->resume)
> > +		hba->vops->resume(hba, pm_op);
> > +set_link_active:
> > +	ufshcd_vreg_set_hpm(hba);
> > +	if (ufshcd_is_link_hibern8(hba) && !ufshcd_uic_hibern8_exit(hba))
> > +		ufshcd_set_link_active(hba);
> > +	else if (ufshcd_is_link_off(hba))
> > +		ufshcd_host_reset_and_restore(hba);
> > +set_dev_active:
> > +	if (!ufshcd_set_dev_pwr_mode(hba, UFS_ACTIVE_PWR_MODE))
> > +		ufshcd_disable_auto_bkops(hba);
> > +out:
> > +	hba->pm_op_in_progress = 0;
> > +	return ret;
> >  }
> > -EXPORT_SYMBOL_GPL(ufshcd_resume);
> >
> > -int ufshcd_runtime_suspend(struct ufs_hba *hba)
> > +/**
> > + * ufshcd_resume - helper function for resume operations
> > + * @hba: per adapter instance
> > + * @pm_op: runtime PM or system PM
> > + *
> > + * This function basically brings the UFS device, UniPro link and
> > +controller
> > + * to active state.
> > + *
> > + * Returns 0 for success and non-zero for failure  */ static int
> > +ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
> >  {
> > -	if (!hba)
> > -		return 0;
> > +	int ret;
> > +	enum uic_link_state old_link_state;
> > +
> > +	hba->pm_op_in_progress = 1;
> > +	old_link_state = hba->uic_link_state;
> > +	/* Make sure clocks are enabled before accessing controller */
> > +	ret = ufshcd_setup_clocks(hba, true);
> > +	if (ret)
> > +		goto out;
> > +
> > +	if (hba->vops && hba->vops->setup_clocks) {
> > +		ret = hba->vops->setup_clocks(hba, true);
> > +		if (ret)
> > +			goto disable_clks;
> > +	}
> > +
> > +	/* enable the host irq as host controller would be active soon */
> > +	ufshcd_enable_irq(hba);
> > +
> > +	ret = ufshcd_vreg_set_hpm(hba);
> > +	if (ret)
> > +		goto disable_irq_and_vops_clks;
> >
> >  	/*
> > -	 * The device is idle with no requests in the queue,
> > -	 * allow background operations.
> > +	 * Call vendor specific resume callback. As these callbacks may access
> > +	 * vendor specific host controller register space call them when the
> > +	 * host clocks are ON.
> >  	 */
> > -	return ufshcd_enable_auto_bkops(hba);
> > +	if (hba->vops && hba->vops->resume) {
> > +		ret = hba->vops->resume(hba, pm_op);
> > +		if (ret)
> > +			goto disable_vreg;
> > +	}
> > +
> > +	if (ufshcd_is_link_hibern8(hba)) {
> > +		ret = ufshcd_uic_hibern8_exit(hba);
> > +		if (!ret)
> > +			ufshcd_set_link_active(hba);
> > +		else
> > +			goto vendor_suspend;
> > +	} else if (ufshcd_is_link_off(hba)) {
> > +		ret = ufshcd_host_reset_and_restore(hba);
> > +		/*
> > +		 * ufshcd_host_reset_and_restore() should have already
> > +		 * set the link state as active
> > +		 */
> > +		if (ret || !ufshcd_is_link_active(hba))
> > +			goto vendor_suspend;
> > +	}
> > +
> > +	if (!ufshcd_is_ufs_dev_active(hba)) {
> > +		ret = ufshcd_set_dev_pwr_mode(hba, UFS_ACTIVE_PWR_MODE);
> > +		if (ret)
> > +			goto set_old_link_state;
> > +	}
> > +
> > +	ufshcd_disable_auto_bkops(hba);

Should be auto background operation enabled again in ufshcd_resume()? It is disabled during ufshcd_suspend().

Thanks
Chuanxiao

> > +	goto out;
> > +
> > +set_old_link_state:
> > +	ufshcd_link_state_transition(hba, old_link_state, 0);
> > +vendor_suspend:
> > +	if (hba->vops && hba->vops->suspend)
> > +		hba->vops->suspend(hba, pm_op);
> > +disable_vreg:
> > +	ufshcd_vreg_set_lpm(hba);
> > +disable_irq_and_vops_clks:
> > +	ufshcd_disable_irq(hba);
> > +	if (hba->vops && hba->vops->setup_clocks)
> > +		ret = hba->vops->setup_clocks(hba, false);
> > +disable_clks:
> > +	ufshcd_setup_clocks(hba, false);
> > +out:
> > +	hba->pm_op_in_progress = 0;
> > +	return ret;
> > +}
> > +
> > +/**
> > + * ufshcd_system_suspend - system suspend routine
> > + * @hba: per adapter instance
> > + * @pm_op: runtime PM or system PM
> > + *
> > + * Check the description of ufshcd_suspend() function for more details.
> > + *
> > + * Returns 0 for success and non-zero for failure  */ int
> > +ufshcd_system_suspend(struct ufs_hba *hba) {
> > +	int ret = 0;
> > +
> > +	if (!hba || !hba->is_powered)
> > +		goto out;
> > +
> > +	if (pm_runtime_suspended(hba->dev)) {
> > +		if (hba->rpm_lvl == hba->spm_lvl)
> > +			/*
> > +			 * There is possibility that device may still be in
> > +			 * active state during the runtime suspend.
> > +			 */
> > +			if ((ufs_get_pm_lvl_to_dev_pwr_mode(hba->spm_lvl) ==
> > +			    hba->curr_dev_pwr_mode)
> > && !hba->auto_bkops_enabled)
> > +				goto out;
> > +
> > +		/*
> > +		 * UFS device and/or UFS link low power states during runtime
> > +		 * suspend seems to be different than what is expected during
> > +		 * system suspend. Hence runtime resume the devic & link and
> > +		 * let the system suspend low power states to take effect.
> > +		 * TODO: If resume takes longer time, we might have optimize
> > +		 * it in future by not resuming everything if possible.
> > +		 */
> > +		ret = ufshcd_runtime_resume(hba);
> > +		if (ret)
> > +			goto out;
> > +	}
> > +
> > +	ret = ufshcd_suspend(hba, UFS_SYSTEM_PM);
> > +out:
> > +	return ret;
> > +}
> > +EXPORT_SYMBOL(ufshcd_system_suspend);
> > +
> > +/**
> > + * ufshcd_system_resume - system resume routine
> > + * @hba: per adapter instance
> > + *
> > + * Returns 0 for success and non-zero for failure  */
> > +
> > +int ufshcd_system_resume(struct ufs_hba *hba) {
> > +	if (!hba || !hba->is_powered || pm_runtime_suspended(hba->dev))
> > +		/*
> > +		 * Let the runtime resume take care of resuming
> > +		 * if runtime suspended.
> > +		 */
> > +		return 0;
> > +	else
> > +		return ufshcd_resume(hba, UFS_SYSTEM_PM); }
> > +EXPORT_SYMBOL(ufshcd_system_resume);
> > +
> > +/**
> > + * ufshcd_runtime_suspend - runtime suspend routine
> > + * @hba: per adapter instance
> > + *
> > + * Check the description of ufshcd_suspend() function for more details.
> > + *
> > + * Returns 0 for success and non-zero for failure  */ int
> > +ufshcd_runtime_suspend(struct ufs_hba *hba) {
> > +	if (!hba || !hba->is_powered)
> > +		return 0;
> > +	else
> > +		return ufshcd_suspend(hba, UFS_RUNTIME_PM);
> >  }
> >  EXPORT_SYMBOL(ufshcd_runtime_suspend);
> >
> > +/**
> > + * ufshcd_runtime_resume - runtime resume routine
> > + * @hba: per adapter instance
> > + *
> > + * This function basically brings the UFS device, UniPro link and
> > +controller
> > + * to active state. Following operations are done in this function:
> > + *
> > + * 1. Turn on all the controller related clocks
> > + * 2. Bring the UniPro link out of Hibernate state
> > + * 3. If UFS device is in sleep state, turn ON VCC rail and bring the UFS device
> > + *    to active state.
> > + * 4. If auto-bkops is enabled on the device, disable it.
> > + *
> > + * So following would be the possible power state after this function
> > +return
> > + * successfully:
> > + *	S1: UFS device in Active state with VCC rail ON
> > + *	    UniPro link in Active state
> > + *	    All the UFS/UniPro controller clocks are ON
> > + *
> > + * Returns 0 for success and non-zero for failure  */
> >  int ufshcd_runtime_resume(struct ufs_hba *hba)  {
> > -	if (!hba)
> > +	if (!hba || !hba->is_powered)
> >  		return 0;
> > -
> > -	return ufshcd_disable_auto_bkops(hba);
> > +	else
> > +		return ufshcd_resume(hba, UFS_RUNTIME_PM);
> >  }
> >  EXPORT_SYMBOL(ufshcd_runtime_resume);
> >
> > @@ -3900,6 +4600,36 @@ int ufshcd_runtime_idle(struct ufs_hba *hba)
> > EXPORT_SYMBOL(ufshcd_runtime_idle);
> >
> >  /**
> > + * ufshcd_shutdown - shutdown routine
> > + * @hba: per adapter instance
> > + *
> > + * This function would power off both UFS device and UFS link.
> > + *
> > + * Returns 0 always to allow force shutdown even in case of errors.
> > + */
> > +int ufshcd_shutdown(struct ufs_hba *hba) {
> > +	int ret = 0;
> > +
> > +	if (ufshcd_is_ufs_dev_poweroff(hba) && ufshcd_is_link_off(hba))
> > +		goto out;
> > +
> > +	if (pm_runtime_suspended(hba->dev)) {
> > +		ret = ufshcd_runtime_resume(hba);
> > +		if (ret)
> > +			goto out;
> > +	}
> > +
> > +	ret = ufshcd_suspend(hba, UFS_SHUTDOWN_PM);
> > +out:
> > +	if (ret)
> > +		dev_err(hba->dev, "%s failed, err %d\n", __func__, ret);
> > +	/* allow force shutdown even in case of errors */
> > +	return 0;
> > +}
> > +EXPORT_SYMBOL(ufshcd_shutdown);
> > +
> > +/**
> >   * ufshcd_remove - de-allocate SCSI host and host memory space
> >   *		data structure memory
> >   * @hba - per adapter instance
> > @@ -4052,6 +4782,8 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem
> > *mmio_base, unsigned int irq)
> >  	if (err) {
> >  		dev_err(hba->dev, "request irq failed\n");
> >  		goto out_disable;
> > +	} else {
> > +		hba->is_irq_enabled = true;
> >  	}
> >
> >  	/* Enable SCSI tag mapping */
> > @@ -4077,6 +4809,12 @@ int ufshcd_init(struct ufs_hba *hba, void
> __iomem
> > *mmio_base, unsigned int irq)
> >  	/* Hold auto suspend until async scan completes */
> >  	pm_runtime_get_sync(dev);
> >
> > +	/*
> > +	 * The device-initialize-sequence hasn't been invoked yet.
> > +	 * Set the device to power-off state
> > +	 */
> > +	ufshcd_set_ufs_dev_poweroff(hba);
> > +
> >  	async_schedule(ufshcd_async_scan, hba);
> >
> >  	return 0;
> > @@ -4084,6 +4822,7 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem
> > *mmio_base, unsigned int irq)
> >  out_remove_scsi_host:
> >  	scsi_remove_host(hba->host);
> >  out_disable:
> > +	hba->is_irq_enabled = false;
> >  	scsi_host_put(host);
> >  	ufshcd_hba_exit(hba);
> >  out_error:
> > diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h index
> > 9b5f77f..1ee429d 100644
> > --- a/drivers/scsi/ufs/ufshcd.h
> > +++ b/drivers/scsi/ufs/ufshcd.h
> > @@ -96,6 +96,54 @@ struct uic_command {
> >  	struct completion done;
> >  };
> >
> > +/* Used to differentiate the power management options */ enum
> ufs_pm_op
> > +{
> > +	UFS_RUNTIME_PM,
> > +	UFS_SYSTEM_PM,
> > +	UFS_SHUTDOWN_PM,
> > +};
> > +
> > +#define ufshcd_is_runtime_pm(op) ((op) == UFS_RUNTIME_PM) #define
> > +ufshcd_is_system_pm(op) ((op) == UFS_SYSTEM_PM) #define
> > +ufshcd_is_shutdown_pm(op) ((op) == UFS_SHUTDOWN_PM)
> > +
> > +/* Host <-> Device UniPro Link state */ enum uic_link_state {
> > +	UIC_LINK_OFF_STATE	= 0, /* Link powered down or disabled */
> > +	UIC_LINK_ACTIVE_STATE	= 1, /* Link is in Fast/Slow/Sleep state */
> > +	UIC_LINK_HIBERN8_STATE	= 2, /* Link is in Hibernate state */
> > +};
> > +
> > +#define ufshcd_is_link_off(hba) ((hba)->uic_link_state ==
> > +UIC_LINK_OFF_STATE) #define ufshcd_is_link_active(hba)
> > ((hba)->uic_link_state == \
> > +				    UIC_LINK_ACTIVE_STATE)
> > +#define ufshcd_is_link_hibern8(hba) ((hba)->uic_link_state == \
> > +				    UIC_LINK_HIBERN8_STATE)
> > +#define ufshcd_set_link_off(hba) ((hba)->uic_link_state =
> > +UIC_LINK_OFF_STATE) #define ufshcd_set_link_active(hba)
> > ((hba)->uic_link_state = \
> > +				    UIC_LINK_ACTIVE_STATE)
> > +#define ufshcd_set_link_hibern8(hba) ((hba)->uic_link_state = \
> > +				    UIC_LINK_HIBERN8_STATE)
> > +
> > +/*
> > + * UFS Power management levels.
> > + * Each level is in increasing order of power savings.
> > + */
> > +enum ufs_pm_level {
> > +	UFS_PM_LVL_0, /* UFS_ACTIVE_PWR_MODE, UIC_LINK_ACTIVE_STATE
> > */
> > +	UFS_PM_LVL_1, /* UFS_ACTIVE_PWR_MODE, UIC_LINK_HIBERN8_STATE
> > */
> > +	UFS_PM_LVL_2, /* UFS_SLEEP_PWR_MODE, UIC_LINK_ACTIVE_STATE */
> > +	UFS_PM_LVL_3, /* UFS_SLEEP_PWR_MODE, UIC_LINK_HIBERN8_STATE
> > */
> > +	UFS_PM_LVL_4, /* UFS_POWERDOWN_PWR_MODE,
> > UIC_LINK_HIBERN8_STATE */
> > +	UFS_PM_LVL_5, /* UFS_POWERDOWN_PWR_MODE,
> > UIC_LINK_OFF_STATE */
> > +	UFS_PM_LVL_MAX
> > +};
> > +
> > +struct ufs_pm_lvl_states {
> > +	enum ufs_dev_pwr_mode dev_state;
> > +	enum uic_link_state link_state;
> > +};
> > +
> >  /**
> >   * struct ufshcd_lrb - local reference block
> >   * @utr_descriptor_ptr: UTRD address of the command @@ -184,6
> +232,8
> > @@ struct ufs_clk_info {
> >   *                     variant specific Uni-Pro initialization.
> >   * @link_startup_notify: called before and after Link startup is carried out
> >   *                       to allow variant specific Uni-Pro
> initialization.
> > + * @suspend: called during host controller PM callback
> > + * @resume: called during host controller PM callback
> >   */
> >  struct ufs_hba_variant_ops {
> >  	const char *name;
> > @@ -193,6 +243,8 @@ struct ufs_hba_variant_ops {
> >  	int     (*setup_regulators)(struct ufs_hba *, bool);
> >  	int     (*hce_enable_notify)(struct ufs_hba *, bool);
> >  	int     (*link_startup_notify)(struct ufs_hba *, bool);
> > +	int     (*suspend)(struct ufs_hba *, enum ufs_pm_op);
> > +	int     (*resume)(struct ufs_hba *, enum ufs_pm_op);
> >  };
> >
> >  /**
> > @@ -271,6 +323,13 @@ struct ufs_hba {
> >  	 * "UFS device" W-LU.
> >  	 */
> >  	struct scsi_device *sdev_ufs_device;
> > +	enum ufs_dev_pwr_mode curr_dev_pwr_mode;
> > +	enum uic_link_state uic_link_state;
> > +	/* Desired UFS power management level during runtime PM */
> > +	enum ufs_pm_level rpm_lvl;
> > +	/* Desired UFS power management level during system PM */
> > +	enum ufs_pm_level spm_lvl;
> > +	int pm_op_in_progress;
> >
> >  	struct ufshcd_lrb *lrb;
> >  	unsigned long lrb_in_use;
> > @@ -285,16 +344,17 @@ struct ufs_hba {
> >  	struct ufs_hba_variant_ops *vops;
> >  	void *priv;
> >  	unsigned int irq;
> > +	bool is_irq_enabled;
> >
> > -	struct uic_command *active_uic_cmd;
> > -	struct mutex uic_cmd_mutex;
> >
> >  	wait_queue_head_t tm_wq;
> >  	wait_queue_head_t tm_tag_wq;
> >  	unsigned long tm_condition;
> >  	unsigned long tm_slots_in_use;
> >
> > -	struct completion *pwr_done;
> > +	struct uic_command *active_uic_cmd;
> > +	struct mutex uic_cmd_mutex;
> > +	struct completion *uic_async_done;
> >
> >  	u32 ufshcd_state;
> >  	u32 eh_flags;
> > @@ -317,9 +377,13 @@ struct ufs_hba {
> >  	/* Device management request data */
> >  	struct ufs_dev_cmd dev_cmd;
> >
> > +	/* Keeps information of the UFS device connected to this host */
> > +	struct ufs_dev_info dev_info;
> >  	bool auto_bkops_enabled;
> >  	struct ufs_vreg_info vreg_info;
> >  	struct list_head clk_list_head;
> > +
> > +	bool wlun_dev_clr_ua;
> >  };
> >
> >  #define ufshcd_writel(hba, val, reg)	\
> > @@ -346,11 +410,12 @@ static inline void check_upiu_size(void)
> >  		GENERAL_UPIU_REQUEST_SIZE + QUERY_DESC_MAX_SIZE);  }
> >
> > -extern int ufshcd_suspend(struct ufs_hba *hba, pm_message_t state);
> > -extern int ufshcd_resume(struct ufs_hba *hba);  extern int
> > ufshcd_runtime_suspend(struct ufs_hba *hba);  extern int
> > ufshcd_runtime_resume(struct ufs_hba *hba);  extern int
> > ufshcd_runtime_idle(struct ufs_hba *hba);
> > +extern int ufshcd_system_suspend(struct ufs_hba *hba); extern int
> > +ufshcd_system_resume(struct ufs_hba *hba); extern int
> > +ufshcd_shutdown(struct ufs_hba *hba);
> >  extern int ufshcd_dme_set_attr(struct ufs_hba *hba, u32 attr_sel,
> >  			       u8 attr_set, u32 mib_val, u8 peer);  extern int
> > ufshcd_dme_get_attr(struct ufs_hba *hba, u32 attr_sel, diff --git
> > a/drivers/scsi/ufs/ufshci.h b/drivers/scsi/ufs/ufshci.h index
> e1b844b..d572119
> > 100644
> > --- a/drivers/scsi/ufs/ufshci.h
> > +++ b/drivers/scsi/ufs/ufshci.h
> > @@ -124,8 +124,11 @@ enum {
> >  #define CONTROLLER_FATAL_ERROR			UFS_BIT(16)
> >  #define SYSTEM_BUS_FATAL_ERROR			UFS_BIT(17)
> >
> > -#define UFSHCD_UIC_MASK		(UIC_COMMAND_COMPL |\
> > -				 UIC_POWER_MODE)
> > +#define UFSHCD_UIC_PWR_MASK	(UIC_HIBERNATE_ENTER |\
> > +				UIC_HIBERNATE_EXIT |\
> > +				UIC_POWER_MODE)
> > +
> > +#define UFSHCD_UIC_MASK		(UIC_COMMAND_COMPL |
> > UFSHCD_UIC_PWR_MASK)
> >
> >  #define UFSHCD_ERROR_MASK	(UIC_ERROR |\
> >  				DEVICE_FATAL_ERROR |\
> > @@ -210,7 +213,7 @@ enum {
> >  #define UIC_GET_ATTR_ID(v)		(((v) >> 16) & 0xFFFF)
> >
> >  /* UIC Commands */
> > -enum {
> > +enum uic_cmd_dme {
> >  	UIC_CMD_DME_GET			= 0x01,
> >  	UIC_CMD_DME_SET			= 0x02,
> >  	UIC_CMD_DME_PEER_GET		= 0x03,
> > --
> > 1.8.5.2
> > --
> > QUALCOMM ISRAEL, on behalf of Qualcomm Innovation Center, Inc. is a
> > member of Code Aurora Forum, hosted by The Linux Foundation
> >
> > --
> > To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body
> > of a message to majordomo@vger.kernel.org More majordomo info at
> > http://vger.kernel.org/majordomo-info.html
> --
> To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [PATCH/RFC V2 10/16] scsi: ufs: add UFS power management support

[hch]

FYI: I won't read your mails until you actually make them readable
by trimming the quotes back to provide just enough context.

Consider this mail (and the one you replied to) unread.

RE: [PATCH/RFC V2 10/16] scsi: ufs: add UFS power management support

[Dolev Raviv]

Hi all,
Thanks for reviewing the patches, I'm sorry for the late replay. I was
waiting for some comments before I address all at once and re-send the
series.

>> > +/**
>> > + * ufshcd_resume - helper function for resume operations
>> > + * @hba: per adapter instance
>> > + * @pm_op: runtime PM or system PM
>> > + *
>> > + * This function basically brings the UFS device, UniPro link and
>> > +controller
>> > + * to active state.
>> > + *
>> > + * Returns 0 for success and non-zero for failure  */ static int
>> > +ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
>> >  {
>> > -	if (!hba)
>> > -		return 0;
>> > +	int ret;
>> > +	enum uic_link_state old_link_state;
>> > +
>> > +	hba->pm_op_in_progress = 1;
>> > +	old_link_state = hba->uic_link_state;
>> > +	/* Make sure clocks are enabled before accessing controller */
>> > +	ret = ufshcd_setup_clocks(hba, true);
>> > +	if (ret)
>> > +		goto out;
>> > +
>> > +	if (hba->vops && hba->vops->setup_clocks) {
>> > +		ret = hba->vops->setup_clocks(hba, true);
>> > +		if (ret)
>> > +			goto disable_clks;
>> > +	}
>> > +
>> > +	/* enable the host irq as host controller would be active soon */
>> > +	ufshcd_enable_irq(hba);
>> > +
>> > +	ret = ufshcd_vreg_set_hpm(hba);
>> > +	if (ret)
>> > +		goto disable_irq_and_vops_clks;
>> >
>> >  	/*
>> > -	 * The device is idle with no requests in the queue,
>> > -	 * allow background operations.
>> > +	 * Call vendor specific resume callback. As these callbacks may
>> access
>> > +	 * vendor specific host controller register space call them when the
>> > +	 * host clocks are ON.
>> >  	 */
>> > -	return ufshcd_enable_auto_bkops(hba);
>> > +	if (hba->vops && hba->vops->resume) {
>> > +		ret = hba->vops->resume(hba, pm_op);
>> > +		if (ret)
>> > +			goto disable_vreg;
>> > +	}
>> > +
>> > +	if (ufshcd_is_link_hibern8(hba)) {
>> > +		ret = ufshcd_uic_hibern8_exit(hba);
>> > +		if (!ret)
>> > +			ufshcd_set_link_active(hba);
>> > +		else
>> > +			goto vendor_suspend;
>> > +	} else if (ufshcd_is_link_off(hba)) {
>> > +		ret = ufshcd_host_reset_and_restore(hba);
>> > +		/*
>> > +		 * ufshcd_host_reset_and_restore() should have already
>> > +		 * set the link state as active
>> > +		 */
>> > +		if (ret || !ufshcd_is_link_active(hba))
>> > +			goto vendor_suspend;
>> > +	}
>> > +
>> > +	if (!ufshcd_is_ufs_dev_active(hba)) {
>> > +		ret = ufshcd_set_dev_pwr_mode(hba, UFS_ACTIVE_PWR_MODE);
>> > +		if (ret)
>> > +			goto set_old_link_state;
>> > +	}
>> > +
>> > +	ufshcd_disable_auto_bkops(hba);
>
> Should be auto background operation enabled again in ufshcd_resume()? It
> is disabled during ufshcd_suspend().
>
> Thanks
> Chuanxiao

Chuanxiao,
If the system is going for runtime suspend, the bkops are enabled if
necessary, and in any case disabled before the suspend. On resume we make
sure, bkops are disabled.

Thanks,
Dolev

>> > --
>> > To unsubscribe from this list: send the line "unsubscribe linux-scsi"
>> in the body
>> > of a message to majordomo@vger.kernel.org More majordomo info at
>> > http://vger.kernel.org/majordomo-info.html
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> --
> To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>


-- 
QUALCOMM ISRAEL, on behalf of Qualcomm Innovation Center, Inc. is a member
of Code Aurora Forum, hosted by The Linux Foundation

RE: [PATCH/RFC V2 10/16] scsi: ufs: add UFS power management support

[Dolev Raviv]

Hi all,
Thanks for reviewing the patches, I'm sorry for the late replay. I was
waiting for some comments before I address all at once and re-send the
series.

>>
>> +static int ufshcd_config_vreg_load(struct device *dev, struct ufs_vreg
>> *vreg,
>> +				   int ua)
>> +{
>> +	int ret = 0;
>> +	struct regulator *reg = vreg->reg;
>> +	const char *name = vreg->name;
>> +
>> +	BUG_ON(!vreg);
>
> For the UFS host controller driver, which doesn't have the ufs_vreg
> structure for vcc and vccq, this function can cause kernel panic due to
> this BUG_ON(). Any reason to put a BUG_ON here instead of a NULL pointer
> checking?
>
> Thanks
> Chuanxiao
>

Sure, I'll fix this.

Thanks,
Dolev

> --
> To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>


-- 
QUALCOMM ISRAEL, on behalf of Qualcomm Innovation Center, Inc. is a member
of Code Aurora Forum, hosted by The Linux Foundation

[PATCH/RFC V2 11/16] scsi: ufs: refactor configuring power mode

[Dolev Raviv]

Sometimes, the device shall report its maximum power and speed
capabilities, but we might not wish to configure it to use those
maximum capabilities.
This change adds support for the vendor specific host driver to
implement power change notify callback.

To enable configuring different power modes (number of lanes,
gear number and fast/slow modes) it is necessary to split the
configuration stage from the stage that reads the device max power mode.
In addition, it is not required to read the configuration more than
once, thus the configuration is stored after reading it once.

Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Yaniv Gardi <ygardi@codeaurora.org>

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index fac71c9..3a66d0d 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -178,6 +178,8 @@ static int ufshcd_clear_tm_cmd(struct ufs_hba *hba, int tag);
 static void ufshcd_hba_exit(struct ufs_hba *hba);
 static int ufshcd_probe_hba(struct ufs_hba *hba);
 static int ufshcd_host_reset_and_restore(struct ufs_hba *hba);
+static int ufshcd_config_pwr_mode(struct ufs_hba *hba,
+		struct ufs_pa_layer_attr *desired_pwr_mode);
 
 static inline void ufshcd_enable_irq(struct ufs_hba *hba)
 {
@@ -1933,65 +1935,129 @@ static int ufshcd_uic_hibern8_exit(struct ufs_hba *hba)
 }
 
 /**
- * ufshcd_config_max_pwr_mode - Set & Change power mode with
- *	maximum capability attribute information.
- * @hba: per adapter instance
- *
- * Returns 0 on success, non-zero value on failure
+ * ufshcd_get_max_pwr_mode - reads the max power mode negotiated with device
+ * @hba: per-adapter instance
  */
-static int ufshcd_config_max_pwr_mode(struct ufs_hba *hba)
+static int ufshcd_get_max_pwr_mode(struct ufs_hba *hba)
 {
-	enum {RX = 0, TX = 1};
-	u32 lanes[] = {1, 1};
-	u32 gear[] = {1, 1};
-	u8 pwr[] = {FASTAUTO_MODE, FASTAUTO_MODE};
-	int ret;
+	struct ufs_pa_layer_attr *pwr_info = &hba->max_pwr_info.info;
+
+	if (hba->max_pwr_info.is_valid)
+		return 0;
+
+	pwr_info->pwr_tx = FASTAUTO_MODE;
+	pwr_info->pwr_rx = FASTAUTO_MODE;
+	pwr_info->hs_rate = PA_HS_MODE_B;
 
 	/* Get the connected lane count */
-	ufshcd_dme_get(hba, UIC_ARG_MIB(PA_CONNECTEDRXDATALANES), &lanes[RX]);
-	ufshcd_dme_get(hba, UIC_ARG_MIB(PA_CONNECTEDTXDATALANES), &lanes[TX]);
+	ufshcd_dme_get(hba, UIC_ARG_MIB(PA_CONNECTEDRXDATALANES),
+			&pwr_info->lane_rx);
+	ufshcd_dme_get(hba, UIC_ARG_MIB(PA_CONNECTEDTXDATALANES),
+			&pwr_info->lane_tx);
+
+	if (!pwr_info->lane_rx || !pwr_info->lane_tx) {
+		dev_err(hba->dev, "%s: invalid connected lanes value. rx=%d, tx=%d\n",
+				__func__,
+				pwr_info->lane_rx,
+				pwr_info->lane_tx);
+		return -EINVAL;
+	}
 
 	/*
 	 * First, get the maximum gears of HS speed.
 	 * If a zero value, it means there is no HSGEAR capability.
 	 * Then, get the maximum gears of PWM speed.
 	 */
-	ufshcd_dme_get(hba, UIC_ARG_MIB(PA_MAXRXHSGEAR), &gear[RX]);
-	if (!gear[RX]) {
-		ufshcd_dme_get(hba, UIC_ARG_MIB(PA_MAXRXPWMGEAR), &gear[RX]);
-		pwr[RX] = SLOWAUTO_MODE;
+	ufshcd_dme_get(hba, UIC_ARG_MIB(PA_MAXRXHSGEAR), &pwr_info->gear_rx);
+	if (!pwr_info->gear_rx) {
+		ufshcd_dme_get(hba, UIC_ARG_MIB(PA_MAXRXPWMGEAR),
+				&pwr_info->gear_rx);
+		if (!pwr_info->gear_rx) {
+			dev_err(hba->dev, "%s: invalid max pwm rx gear read = %d\n",
+				__func__, pwr_info->gear_rx);
+			return -EINVAL;
+		}
+		pwr_info->pwr_rx = SLOWAUTO_MODE;
 	}
 
-	ufshcd_dme_peer_get(hba, UIC_ARG_MIB(PA_MAXRXHSGEAR), &gear[TX]);
-	if (!gear[TX]) {
+	ufshcd_dme_peer_get(hba, UIC_ARG_MIB(PA_MAXRXHSGEAR),
+			&pwr_info->gear_tx);
+	if (!pwr_info->gear_tx) {
 		ufshcd_dme_peer_get(hba, UIC_ARG_MIB(PA_MAXRXPWMGEAR),
-				    &gear[TX]);
-		pwr[TX] = SLOWAUTO_MODE;
+				&pwr_info->gear_tx);
+		if (!pwr_info->gear_tx) {
+			dev_err(hba->dev, "%s: invalid max pwm tx gear read = %d\n",
+				__func__, pwr_info->gear_tx);
+			return -EINVAL;
+		}
+		pwr_info->pwr_tx = SLOWAUTO_MODE;
 	}
 
+	hba->max_pwr_info.is_valid = true;
+	return 0;
+}
+
+/**
+ * ufshcd_config_pwr_mode - configure a new power mode
+ * @hba: per-adapter instance
+ * @desired_pwr_mode: desired power configuration
+ */
+static int ufshcd_config_pwr_mode(struct ufs_hba *hba,
+		struct ufs_pa_layer_attr *desired_pwr_mode)
+{
+	struct ufs_pa_layer_attr final_params = { 0 };
+	int ret;
+
+	if (hba->vops->pwr_change_notify)
+		hba->vops->pwr_change_notify(hba,
+		     PRE_CHANGE, desired_pwr_mode, &final_params);
+	else
+		memcpy(&final_params, desired_pwr_mode, sizeof(final_params));
+
 	/*
 	 * Configure attributes for power mode change with below.
 	 * - PA_RXGEAR, PA_ACTIVERXDATALANES, PA_RXTERMINATION,
 	 * - PA_TXGEAR, PA_ACTIVETXDATALANES, PA_TXTERMINATION,
 	 * - PA_HSSERIES
 	 */
-	ufshcd_dme_set(hba, UIC_ARG_MIB(PA_RXGEAR), gear[RX]);
-	ufshcd_dme_set(hba, UIC_ARG_MIB(PA_ACTIVERXDATALANES), lanes[RX]);
-	if (pwr[RX] == FASTAUTO_MODE)
+	ufshcd_dme_set(hba, UIC_ARG_MIB(PA_RXGEAR), final_params.gear_rx);
+	ufshcd_dme_set(hba, UIC_ARG_MIB(PA_ACTIVERXDATALANES),
+			final_params.lane_rx);
+	if (final_params.pwr_rx == FASTAUTO_MODE ||
+			final_params.pwr_rx == FAST_MODE)
 		ufshcd_dme_set(hba, UIC_ARG_MIB(PA_RXTERMINATION), TRUE);
+	else
+		ufshcd_dme_set(hba, UIC_ARG_MIB(PA_RXTERMINATION), FALSE);
 
-	ufshcd_dme_set(hba, UIC_ARG_MIB(PA_TXGEAR), gear[TX]);
-	ufshcd_dme_set(hba, UIC_ARG_MIB(PA_ACTIVETXDATALANES), lanes[TX]);
-	if (pwr[TX] == FASTAUTO_MODE)
+	ufshcd_dme_set(hba, UIC_ARG_MIB(PA_TXGEAR), final_params.gear_tx);
+	ufshcd_dme_set(hba, UIC_ARG_MIB(PA_ACTIVETXDATALANES),
+			final_params.lane_tx);
+	if (final_params.pwr_tx == FASTAUTO_MODE ||
+			final_params.pwr_tx == FAST_MODE)
 		ufshcd_dme_set(hba, UIC_ARG_MIB(PA_TXTERMINATION), TRUE);
-
-	if (pwr[RX] == FASTAUTO_MODE || pwr[TX] == FASTAUTO_MODE)
-		ufshcd_dme_set(hba, UIC_ARG_MIB(PA_HSSERIES), PA_HS_MODE_B);
-
-	ret = ufshcd_uic_change_pwr_mode(hba, pwr[RX] << 4 | pwr[TX]);
-	if (ret)
+	else
+		ufshcd_dme_set(hba, UIC_ARG_MIB(PA_TXTERMINATION), FALSE);
+
+	if ((final_params.pwr_rx == FASTAUTO_MODE ||
+			final_params.pwr_tx == FASTAUTO_MODE ||
+			final_params.pwr_rx == FAST_MODE ||
+			final_params.pwr_tx == FAST_MODE) &&
+			final_params.hs_rate == PA_HS_MODE_B)
+		ufshcd_dme_set(hba, UIC_ARG_MIB(PA_HSSERIES),
+				final_params.hs_rate);
+
+	ret = ufshcd_uic_change_pwr_mode(hba, final_params.pwr_rx << 4
+			| final_params.pwr_tx);
+	if (ret) {
 		dev_err(hba->dev,
 			"pwr_mode: power mode change failed %d\n", ret);
+	} else {
+		if (hba->vops->pwr_change_notify)
+			hba->vops->pwr_change_notify(hba,
+				POST_CHANGE, NULL, &final_params);
+
+		memcpy(&hba->pwr_info, &final_params, sizeof(final_params));
+	}
 
 	return ret;
 }
@@ -3658,7 +3724,16 @@ static int ufshcd_probe_hba(struct ufs_hba *hba)
 	hba->ufshcd_state = UFSHCD_STATE_OPERATIONAL;
 	hba->wlun_dev_clr_ua = true;
 
-	ufshcd_config_max_pwr_mode(hba);
+	if (ufshcd_get_max_pwr_mode(hba)) {
+		dev_err(hba->dev,
+			"%s: Failed getting max supported power mode\n",
+			__func__);
+	} else {
+		ret = ufshcd_config_pwr_mode(hba, &hba->max_pwr_info.info);
+		if (ret)
+			dev_err(hba->dev, "%s: Failed setting power mode, err = %d\n",
+					__func__, ret);
+	}
 
 	/*
 	 * If we are in error handling context or in power management callbacks
@@ -4760,6 +4835,8 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq)
 	host->max_cmd_len = MAX_CDB_SIZE;
 	host->report_wlus = 1;
 
+	hba->max_pwr_info.is_valid = false;
+
 	/* Initailize wait queue for task management */
 	init_waitqueue_head(&hba->tm_wq);
 	init_waitqueue_head(&hba->tm_tag_wq);
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index 1ee429d..caebdcb 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -221,6 +221,22 @@ struct ufs_clk_info {
 
 #define PRE_CHANGE      0
 #define POST_CHANGE     1
+
+struct ufs_pa_layer_attr {
+	u32 gear_rx;
+	u32 gear_tx;
+	u32 lane_rx;
+	u32 lane_tx;
+	u32 pwr_rx;
+	u32 pwr_tx;
+	u32 hs_rate;
+};
+
+struct ufs_pwr_mode_info {
+	bool is_valid;
+	struct ufs_pa_layer_attr info;
+};
+
 /**
  * struct ufs_hba_variant_ops - variant specific callbacks
  * @name: variant name
@@ -232,6 +248,9 @@ struct ufs_clk_info {
  *                     variant specific Uni-Pro initialization.
  * @link_startup_notify: called before and after Link startup is carried out
  *                       to allow variant specific Uni-Pro initialization.
+ * @pwr_change_notify: called before and after a power mode change
+ *			is carried out to allow vendor spesific capabilities
+ *			to be set.
  * @suspend: called during host controller PM callback
  * @resume: called during host controller PM callback
  */
@@ -243,6 +262,9 @@ struct ufs_hba_variant_ops {
 	int     (*setup_regulators)(struct ufs_hba *, bool);
 	int     (*hce_enable_notify)(struct ufs_hba *, bool);
 	int     (*link_startup_notify)(struct ufs_hba *, bool);
+	int	(*pwr_change_notify)(struct ufs_hba *,
+					bool, struct ufs_pa_layer_attr *,
+					struct ufs_pa_layer_attr *);
 	int     (*suspend)(struct ufs_hba *, enum ufs_pm_op);
 	int     (*resume)(struct ufs_hba *, enum ufs_pm_op);
 };
@@ -302,6 +324,8 @@ struct ufs_init_prefetch {
  * @auto_bkops_enabled: to track whether bkops is enabled in device
  * @vreg_info: UFS device voltage regulator information
  * @clk_list_head: UFS host controller clocks list node head
+ * @pwr_info: holds current power mode
+ * @max_pwr_info: keeps the device max valid pwm
  */
 struct ufs_hba {
 	void __iomem *mmio_base;
@@ -384,6 +408,9 @@ struct ufs_hba {
 	struct list_head clk_list_head;
 
 	bool wlun_dev_clr_ua;
+
+	struct ufs_pa_layer_attr pwr_info;
+	struct ufs_pwr_mode_info max_pwr_info;
 };
 
 #define ufshcd_writel(hba, val, reg)	\
-- 
1.8.5.2
-- 
QUALCOMM ISRAEL, on behalf of Qualcomm Innovation Center, Inc. is a member
of Code Aurora Forum, hosted by The Linux Foundation

[PATCH/RFC V2 12/16] scsi: ufs: Add support for clock gating

[Dolev Raviv]

From: Sahitya Tummala <stummala@codeaurora.org>

The UFS controller clocks can be gated after certain period of
inactivity, which is typically less than runtime suspend timeout.
In addition to clocks the link will also be put into Hibern8 mode
to save more power.

The clock gating can be turned on by enabling the capability
UFSHCD_CAP_CLK_GATING. To enable entering into Hibern8 mode as part of
clock gating, set the capability UFSHCD_CAP_HIBERN8_WITH_CLK_GATING.

The tracing events for clock gating can be enabled through debugfs as:
echo 1 > /sys/kernel/debug/tracing/events/ufs/ufshcd_clk_gating/enable
cat /sys/kernel/debug/tracing/trace_pipe

Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 3a66d0d..1e5219c 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -177,6 +177,11 @@ static int ufshcd_reset_and_restore(struct ufs_hba *hba);
 static int ufshcd_clear_tm_cmd(struct ufs_hba *hba, int tag);
 static void ufshcd_hba_exit(struct ufs_hba *hba);
 static int ufshcd_probe_hba(struct ufs_hba *hba);
+static int __ufshcd_setup_clocks(struct ufs_hba *hba, bool on,
+				 bool skip_ref_clk);
+static int ufshcd_setup_clocks(struct ufs_hba *hba, bool on);
+static int ufshcd_uic_hibern8_exit(struct ufs_hba *hba);
+static int ufshcd_uic_hibern8_enter(struct ufs_hba *hba);
 static int ufshcd_host_reset_and_restore(struct ufs_hba *hba);
 static int ufshcd_config_pwr_mode(struct ufs_hba *hba,
 		struct ufs_pa_layer_attr *desired_pwr_mode);
@@ -498,6 +503,231 @@ static inline int ufshcd_is_hba_active(struct ufs_hba *hba)
 	return (ufshcd_readl(hba, REG_CONTROLLER_ENABLE) & 0x1) ? 0 : 1;
 }
 
+static void ufshcd_ungate_work(struct work_struct *work)
+{
+	int ret;
+	unsigned long flags;
+	struct ufs_hba *hba = container_of(work, struct ufs_hba,
+			clk_gating.ungate_work);
+
+	cancel_delayed_work_sync(&hba->clk_gating.gate_work);
+
+	spin_lock_irqsave(hba->host->host_lock, flags);
+	if (hba->clk_gating.state == CLKS_ON) {
+		spin_unlock_irqrestore(hba->host->host_lock, flags);
+		goto unblock_reqs;
+	}
+
+	spin_unlock_irqrestore(hba->host->host_lock, flags);
+	ufshcd_setup_clocks(hba, true);
+
+	/* Exit from hibern8 */
+	if (ufshcd_can_hibern8_during_gating(hba)) {
+		/* Prevent gating in this path */
+		hba->clk_gating.is_suspended = true;
+		if (ufshcd_is_link_hibern8(hba)) {
+			ret = ufshcd_uic_hibern8_exit(hba);
+			if (ret)
+				dev_err(hba->dev, "%s: hibern8 exit failed %d\n",
+					__func__, ret);
+			else
+				ufshcd_set_link_active(hba);
+		}
+		hba->clk_gating.is_suspended = false;
+	}
+unblock_reqs:
+	scsi_unblock_requests(hba->host);
+}
+
+/**
+ * ufshcd_hold - Enable clocks that were gated earlier due to ufshcd_release.
+ * Also, exit from hibern8 mode and set the link as active.
+ * @hba: per adapter instance
+ * @async: This indicates whether caller should ungate clocks asynchronously.
+ */
+int ufshcd_hold(struct ufs_hba *hba, bool async)
+{
+	int rc = 0;
+	unsigned long flags;
+
+	if (!ufshcd_is_clkgating_allowed(hba))
+		goto out;
+start:
+	spin_lock_irqsave(hba->host->host_lock, flags);
+	hba->clk_gating.active_reqs++;
+
+	switch (hba->clk_gating.state) {
+	case CLKS_ON:
+		break;
+	case REQ_CLKS_OFF:
+		if (cancel_delayed_work(&hba->clk_gating.gate_work)) {
+			hba->clk_gating.state = CLKS_ON;
+			break;
+		}
+		/*
+		 * If we here, it means gating work is either done or
+		 * currently running. Hence, fall through to cancel gating
+		 * work and to enable clocks.
+		 */
+	case CLKS_OFF:
+		scsi_block_requests(hba->host);
+		hba->clk_gating.state = REQ_CLKS_ON;
+		schedule_work(&hba->clk_gating.ungate_work);
+		/*
+		 * fall through to check if we should wait for this
+		 * work to be done or not.
+		 */
+	case REQ_CLKS_ON:
+		if (async) {
+			rc = -EAGAIN;
+			hba->clk_gating.active_reqs--;
+			break;
+		} else {
+			spin_unlock_irqrestore(hba->host->host_lock, flags);
+			flush_work(&hba->clk_gating.ungate_work);
+			/* Make sure state is CLKS_ON before returning */
+			goto start;
+		}
+	default:
+		dev_err(hba->dev, "%s: clk gating is in invalid state %d\n",
+				__func__, hba->clk_gating.state);
+		break;
+	}
+	spin_unlock_irqrestore(hba->host->host_lock, flags);
+out:
+	return rc;
+}
+
+static void ufshcd_gate_work(struct work_struct *work)
+{
+	struct ufs_hba *hba = container_of(work, struct ufs_hba,
+			clk_gating.gate_work.work);
+	unsigned long flags;
+
+	spin_lock_irqsave(hba->host->host_lock, flags);
+	if (hba->clk_gating.is_suspended) {
+		hba->clk_gating.state = CLKS_ON;
+		goto rel_lock;
+	}
+
+	if (hba->clk_gating.active_reqs
+		|| hba->ufshcd_state != UFSHCD_STATE_OPERATIONAL
+		|| hba->lrb_in_use || hba->outstanding_tasks
+		|| hba->active_uic_cmd || hba->uic_async_done)
+		goto rel_lock;
+
+	spin_unlock_irqrestore(hba->host->host_lock, flags);
+
+	/* put the link into hibern8 mode before turning off clocks */
+	if (ufshcd_can_hibern8_during_gating(hba)) {
+		if (ufshcd_uic_hibern8_enter(hba)) {
+			hba->clk_gating.state = CLKS_ON;
+			goto out;
+		}
+		ufshcd_set_link_hibern8(hba);
+	}
+
+	if (!ufshcd_is_link_active(hba))
+		ufshcd_setup_clocks(hba, false);
+	else
+		/* If link is active, device ref_clk can't be switched off */
+		__ufshcd_setup_clocks(hba, false, true);
+
+	/*
+	 * In case you are here to cancel this work the gating state
+	 * would be marked as REQ_CLKS_ON. In this case keep the state
+	 * as REQ_CLKS_ON which would anyway imply that clocks are off
+	 * and a request to turn them on is pending. By doing this way,
+	 * we keep the state machine in tact and this would ultimately
+	 * prevent from doing cancel work multiple times when there are
+	 * new requests arriving before the current cancel work is done.
+	 */
+	spin_lock_irqsave(hba->host->host_lock, flags);
+	if (hba->clk_gating.state == REQ_CLKS_OFF) {
+		hba->clk_gating.state = CLKS_OFF;
+	}
+rel_lock:
+	spin_unlock_irqrestore(hba->host->host_lock, flags);
+out:
+	return;
+}
+
+/* host lock must be held before calling this variant */
+static void __ufshcd_release(struct ufs_hba *hba)
+{
+	if (!ufshcd_is_clkgating_allowed(hba))
+		return;
+
+	hba->clk_gating.active_reqs--;
+
+	if (hba->clk_gating.active_reqs || hba->clk_gating.is_suspended
+		|| hba->ufshcd_state != UFSHCD_STATE_OPERATIONAL
+		|| hba->lrb_in_use || hba->outstanding_tasks
+		|| hba->active_uic_cmd || hba->uic_async_done)
+		return;
+
+	hba->clk_gating.state = REQ_CLKS_OFF;
+	schedule_delayed_work(&hba->clk_gating.gate_work,
+			msecs_to_jiffies(hba->clk_gating.delay_ms));
+}
+
+void ufshcd_release(struct ufs_hba *hba)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(hba->host->host_lock, flags);
+	__ufshcd_release(hba);
+	spin_unlock_irqrestore(hba->host->host_lock, flags);
+}
+
+static ssize_t ufshcd_clkgate_delay_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct ufs_hba *hba = dev_get_drvdata(dev);
+
+	return snprintf(buf, PAGE_SIZE, "%lu\n", hba->clk_gating.delay_ms);
+}
+
+static ssize_t ufshcd_clkgate_delay_store(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct ufs_hba *hba = dev_get_drvdata(dev);
+	unsigned long flags, value;
+
+	if (kstrtoul(buf, 0, &value))
+		return -EINVAL;
+
+	spin_lock_irqsave(hba->host->host_lock, flags);
+	hba->clk_gating.delay_ms = value;
+	spin_unlock_irqrestore(hba->host->host_lock, flags);
+	return count;
+}
+
+static void ufshcd_init_clk_gating(struct ufs_hba *hba)
+{
+	if (!ufshcd_is_clkgating_allowed(hba))
+		return;
+
+	hba->clk_gating.delay_ms = 150;
+	INIT_DELAYED_WORK(&hba->clk_gating.gate_work, ufshcd_gate_work);
+	INIT_WORK(&hba->clk_gating.ungate_work, ufshcd_ungate_work);
+
+	hba->clk_gating.delay_attr.show = ufshcd_clkgate_delay_show;
+	hba->clk_gating.delay_attr.store = ufshcd_clkgate_delay_store;
+	sysfs_attr_init(&hba->clk_gating.delay_attr.attr);
+	hba->clk_gating.delay_attr.attr.name = "clkgate_delay_ms";
+	hba->clk_gating.delay_attr.attr.mode = S_IRUGO | S_IWUSR;
+	if (device_create_file(hba->dev, &hba->clk_gating.delay_attr))
+		dev_err(hba->dev, "Failed to create sysfs for clkgate_delay\n");
+}
+
+static void ufshcd_exit_clk_gating(struct ufs_hba *hba)
+{
+	if (!ufshcd_is_clkgating_allowed(hba))
+		return;
+	device_remove_file(hba->dev, &hba->clk_gating.delay_attr);
+}
+
 /**
  * ufshcd_send_command - Send SCSI or device management commands
  * @hba: per adapter instance
@@ -699,10 +929,12 @@ ufshcd_send_uic_cmd(struct ufs_hba *hba, struct uic_command *uic_cmd)
 {
 	int ret;
 
+	ufshcd_hold(hba, false);
 	mutex_lock(&hba->uic_cmd_mutex);
 	ret = __ufshcd_send_uic_cmd(hba, uic_cmd);
 	mutex_unlock(&hba->uic_cmd_mutex);
 
+	ufshcd_release(hba);
 	return ret;
 }
 
@@ -1018,6 +1250,14 @@ static int ufshcd_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd)
 		goto out;
 	}
 
+	err = ufshcd_hold(hba, true);
+	if (err) {
+		err = SCSI_MLQUEUE_HOST_BUSY;
+		clear_bit_unlock(tag, &hba->lrb_in_use);
+		goto out;
+	}
+	WARN_ON(hba->clk_gating.state != CLKS_ON);
+
 	lrbp = &hba->lrb[tag];
 
 	WARN_ON(lrbp->cmd);
@@ -1293,6 +1533,7 @@ static int ufshcd_query_flag(struct ufs_hba *hba, enum query_opcode opcode,
 
 	BUG_ON(!hba);
 
+	ufshcd_hold(hba, false);
 	mutex_lock(&hba->dev_cmd.lock);
 	ufshcd_init_query(hba, &request, &response, opcode, idn, index,
 			selector);
@@ -1336,6 +1577,7 @@ static int ufshcd_query_flag(struct ufs_hba *hba, enum query_opcode opcode,
 
 out_unlock:
 	mutex_unlock(&hba->dev_cmd.lock);
+	ufshcd_release(hba);
 	return err;
 }
 
@@ -1359,6 +1601,7 @@ static int ufshcd_query_attr(struct ufs_hba *hba, enum query_opcode opcode,
 
 	BUG_ON(!hba);
 
+	ufshcd_hold(hba, false);
 	if (!attr_val) {
 		dev_err(hba->dev, "%s: attribute value required for opcode 0x%x\n",
 				__func__, opcode);
@@ -1398,6 +1641,7 @@ static int ufshcd_query_attr(struct ufs_hba *hba, enum query_opcode opcode,
 out_unlock:
 	mutex_unlock(&hba->dev_cmd.lock);
 out:
+	ufshcd_release(hba);
 	return err;
 }
 
@@ -1425,6 +1669,7 @@ static int ufshcd_query_descriptor(struct ufs_hba *hba,
 
 	BUG_ON(!hba);
 
+	ufshcd_hold(hba, false);
 	if (!desc_buf) {
 		dev_err(hba->dev, "%s: descriptor buffer required for opcode 0x%x\n",
 				__func__, opcode);
@@ -1474,6 +1719,7 @@ static int ufshcd_query_descriptor(struct ufs_hba *hba,
 out_unlock:
 	mutex_unlock(&hba->dev_cmd.lock);
 out:
+	ufshcd_release(hba);
 	return err;
 }
 
@@ -1852,6 +2098,7 @@ int ufshcd_uic_pwr_ctrl(struct ufs_hba *hba, struct uic_command *cmd)
 	u8 status;
 	int ret;
 
+	ufshcd_hold(hba, false);
 	mutex_lock(&hba->uic_cmd_mutex);
 	init_completion(&uic_async_done);
 
@@ -1888,6 +2135,8 @@ out:
 	hba->uic_async_done = NULL;
 	spin_unlock_irqrestore(hba->host->host_lock, flags);
 	mutex_unlock(&hba->uic_cmd_mutex);
+
+	ufshcd_release(hba);
 	return ret;
 }
 
@@ -2306,6 +2555,7 @@ static int ufshcd_verify_dev_init(struct ufs_hba *hba)
 	int err = 0;
 	int retries;
 
+	ufshcd_hold(hba, false);
 	mutex_lock(&hba->dev_cmd.lock);
 	for (retries = NOP_OUT_RETRIES; retries > 0; retries--) {
 		err = ufshcd_exec_dev_cmd(hba, DEV_CMD_TYPE_NOP,
@@ -2317,6 +2567,7 @@ static int ufshcd_verify_dev_init(struct ufs_hba *hba)
 		dev_dbg(hba->dev, "%s: error %d retrying\n", __func__, err);
 	}
 	mutex_unlock(&hba->dev_cmd.lock);
+	ufshcd_release(hba);
 
 	if (err)
 		dev_err(hba->dev, "%s: NOP OUT failed %d\n", __func__, err);
@@ -2729,6 +2980,7 @@ static void ufshcd_transfer_req_compl(struct ufs_hba *hba)
 			clear_bit_unlock(index, &hba->lrb_in_use);
 			/* Do not touch lrbp after scsi done */
 			cmd->scsi_done(cmd);
+			__ufshcd_release(hba);
 		} else if (lrbp->command_type == UTP_CMD_TYPE_DEV_MANAGE) {
 			if (hba->dev_cmd.complete)
 				complete(hba->dev_cmd.complete);
@@ -3013,6 +3265,7 @@ static void ufshcd_err_handler(struct work_struct *work)
 	hba = container_of(work, struct ufs_hba, eh_work);
 
 	pm_runtime_get_sync(hba->dev);
+	ufshcd_hold(hba, false);
 
 	spin_lock_irqsave(hba->host->host_lock, flags);
 	if (hba->ufshcd_state == UFSHCD_STATE_RESET) {
@@ -3066,6 +3319,7 @@ static void ufshcd_err_handler(struct work_struct *work)
 
 out:
 	scsi_unblock_requests(hba->host);
+	ufshcd_release(hba);
 	pm_runtime_put_sync(hba->dev);
 }
 
@@ -3249,6 +3503,7 @@ static int ufshcd_issue_tm_cmd(struct ufs_hba *hba, int lun_id, int task_id,
 	 * the maximum wait time is bounded by %TM_CMD_TIMEOUT.
 	 */
 	wait_event(hba->tm_tag_wq, ufshcd_get_tm_free_slot(hba, &free_slot));
+	ufshcd_hold(hba, false);
 
 	spin_lock_irqsave(host->host_lock, flags);
 	task_req_descp = hba->utmrdl_base_addr;
@@ -3300,6 +3555,7 @@ static int ufshcd_issue_tm_cmd(struct ufs_hba *hba, int lun_id, int task_id,
 	ufshcd_put_tm_slot(hba, free_slot);
 	wake_up(&hba->tm_tag_wq);
 
+	ufshcd_release(hba);
 	return err;
 }
 
@@ -3382,6 +3638,7 @@ static int ufshcd_abort(struct scsi_cmnd *cmd)
 	hba = shost_priv(host);
 	tag = cmd->request->tag;
 
+	ufshcd_hold(hba, false);
 	/* If command is already aborted/completed, return SUCCESS */
 	if (!(test_bit(tag, &hba->outstanding_reqs)))
 		goto out;
@@ -3446,6 +3703,11 @@ static int ufshcd_abort(struct scsi_cmnd *cmd)
 
 	clear_bit_unlock(tag, &hba->lrb_in_use);
 	wake_up(&hba->dev_cmd.tag_wq);
+	/*
+	 * This ufshcd_release() corresponds to the original scsi cmd that got
+	 * aborted here (as we won't get any IRQ for it).
+	 */
+	ufshcd_release(hba);
 out:
 	if (!err) {
 		err = SUCCESS;
@@ -3453,7 +3715,7 @@ out:
 		dev_err(hba->dev, "%s: failed with err %d\n", __func__, err);
 		err = FAILED;
 	}
-
+	ufshcd_release(hba);
 	return err;
 }
 
@@ -3538,6 +3800,7 @@ static int ufshcd_eh_host_reset_handler(struct scsi_cmnd *cmd)
 
 	hba = shost_priv(cmd->device->host);
 
+	ufshcd_hold(hba, false);
 	/*
 	 * Check if there is any race with fatal error handling.
 	 * If so, wait for it to complete. Even though fatal error
@@ -3571,6 +3834,7 @@ static int ufshcd_eh_host_reset_handler(struct scsi_cmnd *cmd)
 	ufshcd_clear_eh_in_progress(hba);
 	spin_unlock_irqrestore(hba->host->host_lock, flags);
 
+	ufshcd_release(hba);
 	return err;
 }
 
@@ -3798,6 +4062,7 @@ static struct scsi_host_template ufshcd_driver_template = {
 	.sg_tablesize		= SG_ALL,
 	.cmd_per_lun		= UFSHCD_CMD_PER_LUN,
 	.can_queue		= UFSHCD_CAN_QUEUE,
+	.max_host_blocked	= 1,
 };
 
 static int ufshcd_config_vreg_load(struct device *dev, struct ufs_vreg *vreg,
@@ -3980,6 +4245,7 @@ static int __ufshcd_setup_clocks(struct ufs_hba *hba, bool on,
 	int ret = 0;
 	struct ufs_clk_info *clki;
 	struct list_head *head = &hba->clk_list_head;
+	unsigned long flags;
 
 	if (!head || list_empty(head))
 		goto out;
@@ -4004,12 +4270,19 @@ static int __ufshcd_setup_clocks(struct ufs_hba *hba, bool on,
 					clki->name, on ? "en" : "dis");
 		}
 	}
+
+	if (hba->vops && hba->vops->setup_clocks)
+		ret = hba->vops->setup_clocks(hba, on);
 out:
 	if (ret) {
 		list_for_each_entry(clki, head, list) {
 			if (!IS_ERR_OR_NULL(clki->clk) && clki->enabled)
 				clk_disable_unprepare(clki->clk);
 		}
+	} else if (!ret && on) {
+		spin_lock_irqsave(hba->host->host_lock, flags);
+		hba->clk_gating.state = CLKS_ON;
+		spin_unlock_irqrestore(hba->host->host_lock, flags);
 	}
 	return ret;
 }
@@ -4070,23 +4343,14 @@ static int ufshcd_variant_hba_init(struct ufs_hba *hba)
 			goto out;
 	}
 
-	if (hba->vops->setup_clocks) {
-		err = hba->vops->setup_clocks(hba, true);
-		if (err)
-			goto out_exit;
-	}
-
 	if (hba->vops->setup_regulators) {
 		err = hba->vops->setup_regulators(hba, true);
 		if (err)
-			goto out_clks;
+			goto out_exit;
 	}
 
 	goto out;
 
-out_clks:
-	if (hba->vops->setup_clocks)
-		hba->vops->setup_clocks(hba, false);
 out_exit:
 	if (hba->vops->exit)
 		hba->vops->exit(hba);
@@ -4378,6 +4642,9 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 	 * If we can't transition into any of the low power modes
 	 * just gate the clocks.
 	 */
+	ufshcd_hold(hba, false);
+	hba->clk_gating.is_suspended = true;
+
 	if (req_dev_pwr_mode == UFS_ACTIVE_PWR_MODE &&
 			req_link_state == UIC_LINK_ACTIVE_STATE) {
 		goto disable_clks;
@@ -4400,7 +4667,7 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 		 */
 		ret = ufshcd_bkops_ctrl(hba, BKOPS_STATUS_NON_CRITICAL);
 		if (ret)
-			goto out;
+			goto enable_gating;
 	}
 
 	if ((req_dev_pwr_mode != hba->curr_dev_pwr_mode) &&
@@ -4410,7 +4677,7 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 		ufshcd_disable_auto_bkops(hba);
 		ret = ufshcd_set_dev_pwr_mode(hba, req_dev_pwr_mode);
 		if (ret)
-			goto out;
+			goto enable_gating;
 	}
 
 	ret = ufshcd_link_state_transition(hba, req_link_state, 1);
@@ -4443,6 +4710,7 @@ disable_clks:
 		/* If link is active, device ref_clk can't be switched off */
 		__ufshcd_setup_clocks(hba, false, true);
 
+	hba->clk_gating.state = CLKS_OFF;
 	/*
 	 * Disable the host irq as host controller as there won't be any
 	 * host controller trasanction expected till resume.
@@ -4462,6 +4730,9 @@ set_link_active:
 set_dev_active:
 	if (!ufshcd_set_dev_pwr_mode(hba, UFS_ACTIVE_PWR_MODE))
 		ufshcd_disable_auto_bkops(hba);
+enable_gating:
+	hba->clk_gating.is_suspended = false;
+	ufshcd_release(hba);
 out:
 	hba->pm_op_in_progress = 0;
 	return ret;
@@ -4489,12 +4760,6 @@ static int ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 	if (ret)
 		goto out;
 
-	if (hba->vops && hba->vops->setup_clocks) {
-		ret = hba->vops->setup_clocks(hba, true);
-		if (ret)
-			goto disable_clks;
-	}
-
 	/* enable the host irq as host controller would be active soon */
 	ufshcd_enable_irq(hba);
 
@@ -4536,6 +4801,10 @@ static int ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 	}
 
 	ufshcd_disable_auto_bkops(hba);
+	hba->clk_gating.is_suspended = false;
+
+	/* Schedule clock gating in case of no access to UFS device yet */
+	ufshcd_release(hba);
 	goto out;
 
 set_old_link_state:
@@ -4547,9 +4816,6 @@ disable_vreg:
 	ufshcd_vreg_set_lpm(hba);
 disable_irq_and_vops_clks:
 	ufshcd_disable_irq(hba);
-	if (hba->vops && hba->vops->setup_clocks)
-		ret = hba->vops->setup_clocks(hba, false);
-disable_clks:
 	ufshcd_setup_clocks(hba, false);
 out:
 	hba->pm_op_in_progress = 0;
@@ -4718,6 +4984,7 @@ void ufshcd_remove(struct ufs_hba *hba)
 
 	scsi_host_put(hba->host);
 
+	ufshcd_exit_clk_gating(hba);
 	ufshcd_hba_exit(hba);
 }
 EXPORT_SYMBOL_GPL(ufshcd_remove);
@@ -4854,11 +5121,12 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq)
 	/* Initialize device management tag acquire wait queue */
 	init_waitqueue_head(&hba->dev_cmd.tag_wq);
 
+	ufshcd_init_clk_gating(hba);
 	/* IRQ registration */
 	err = devm_request_irq(dev, irq, ufshcd_intr, IRQF_SHARED, UFSHCD, hba);
 	if (err) {
 		dev_err(hba->dev, "request irq failed\n");
-		goto out_disable;
+		goto exit_gating;
 	} else {
 		hba->is_irq_enabled = true;
 	}
@@ -4867,13 +5135,13 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq)
 	err = scsi_init_shared_tag_map(host, host->can_queue);
 	if (err) {
 		dev_err(hba->dev, "init shared queue failed\n");
-		goto out_disable;
+		goto exit_gating;
 	}
 
 	err = scsi_add_host(host, hba->dev);
 	if (err) {
 		dev_err(hba->dev, "scsi_add_host failed\n");
-		goto out_disable;
+		goto exit_gating;
 	}
 
 	/* Host controller enable */
@@ -4898,6 +5166,8 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq)
 
 out_remove_scsi_host:
 	scsi_remove_host(hba->host);
+exit_gating:
+	ufshcd_exit_clk_gating(hba);
 out_disable:
 	hba->is_irq_enabled = false;
 	scsi_host_put(host);
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index caebdcb..93c7c82 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -269,6 +269,38 @@ struct ufs_hba_variant_ops {
 	int     (*resume)(struct ufs_hba *, enum ufs_pm_op);
 };
 
+/* clock gating state  */
+enum clk_gating_state {
+	CLKS_OFF,
+	CLKS_ON,
+	REQ_CLKS_OFF,
+	REQ_CLKS_ON,
+};
+
+/**
+ * struct ufs_clk_gating - UFS clock gating related info
+ * @gate_work: worker to turn off clocks after some delay as specified in
+ * delay_ms
+ * @ungate_work: worker to turn on clocks that will be used in case of
+ * interrupt context
+ * @state: the current clocks state
+ * @delay_ms: gating delay in ms
+ * @is_suspended: clk gating is suspended when set to 1 which can be used
+ * during suspend/resume
+ * @delay_attr: sysfs attribute to control delay_attr
+ * @active_reqs: number of requests that are pending and should be waited for
+ * completion before gating clocks.
+ */
+struct ufs_clk_gating {
+	struct delayed_work gate_work;
+	struct work_struct ungate_work;
+	enum clk_gating_state state;
+	unsigned long delay_ms;
+	bool is_suspended;
+	struct device_attribute delay_attr;
+	int active_reqs;
+};
+
 /**
  * struct ufs_init_prefetch - contains data that is pre-fetched once during
  * initialization
@@ -411,8 +443,25 @@ struct ufs_hba {
 
 	struct ufs_pa_layer_attr pwr_info;
 	struct ufs_pwr_mode_info max_pwr_info;
+
+	struct ufs_clk_gating clk_gating;
+	/* Control to enable/disable host capabilities */
+	u32 caps;
+	/* Allow dynamic clk gating */
+#define UFSHCD_CAP_CLK_GATING	(1 << 0)
+	/* Allow hiberb8 with clk gating */
+#define UFSHCD_CAP_HIBERN8_WITH_CLK_GATING (1 << 1)
 };
 
+/* Returns true if clocks can be gated. Otherwise false */
+static inline bool ufshcd_is_clkgating_allowed(struct ufs_hba *hba)
+{
+	return hba->caps & UFSHCD_CAP_CLK_GATING;
+}
+static inline bool ufshcd_can_hibern8_during_gating(struct ufs_hba *hba)
+{
+	return hba->caps & UFSHCD_CAP_HIBERN8_WITH_CLK_GATING;
+}
 #define ufshcd_writel(hba, val, reg)	\
 	writel((val), (hba)->mmio_base + (reg))
 #define ufshcd_readl(hba, reg)	\
@@ -494,4 +543,6 @@ static inline int ufshcd_dme_peer_get(struct ufs_hba *hba,
 	return ufshcd_dme_get_attr(hba, attr_sel, mib_val, DME_PEER);
 }
 
+int ufshcd_hold(struct ufs_hba *hba, bool async);
+void ufshcd_release(struct ufs_hba *hba);
 #endif /* End of Header */
-- 
1.8.5.2
-- 
QUALCOMM ISRAEL, on behalf of Qualcomm Innovation Center, Inc. is a member
of Code Aurora Forum, hosted by The Linux Foundation

[PATCH/RFC V2 13/16] scsi: ufs: Add freq-table-hz property for UFS device

[Dolev Raviv]

From: Sahitya Tummala <stummala@codeaurora.org>

Add freq-table-hz propery for UFS device to keep track of
<min max> frequencies supported by UFS clocks.

Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>

diff --git a/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt b/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt
index b0f791a..e73a619 100644
--- a/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt
+++ b/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt
@@ -24,11 +24,11 @@ Optional properties:
 - clocks                : List of phandle and clock specifier pairs
 - clock-names           : List of clock input name strings sorted in the same
                           order as the clocks property.
-- max-clock-frequency-hz : List of maximum operating frequency stored in the same
-                           order as the clocks property. If this property is not
-			   defined or a value in the array is "0" then it is assumed
-			   that the frequency is set by the parent clock or a
-			   fixed rate clock source.
+- freq-table-hz		: Array of <min max> operating frequencies stored in the same
+                          order as the clocks property. If this property is not
+			  defined or a value in the array is "0" then it is assumed
+			  that the frequency is set by the parent clock or a
+			  fixed rate clock source.
 
 Note: If above properties are not defined it can be assumed that the supply
 regulators or clocks are always on.
@@ -49,5 +49,5 @@ Example:
 
 		clocks = <&core 0>, <&ref 0>, <&iface 0>;
 		clock-names = "core_clk", "ref_clk", "iface_clk";
-		max-clock-frequency-hz = <100000000 19200000 0>;
+		freq-table-hz = <100000000 200000000>, <0 0>, <0 0>;
 	};
diff --git a/drivers/scsi/ufs/ufshcd-pltfrm.c b/drivers/scsi/ufs/ufshcd-pltfrm.c
index edaccd0..551be95 100644
--- a/drivers/scsi/ufs/ufshcd-pltfrm.c
+++ b/drivers/scsi/ufs/ufshcd-pltfrm.c
@@ -63,6 +63,8 @@ static int ufshcd_parse_clock_info(struct ufs_hba *hba)
 	char *name;
 	u32 *clkfreq = NULL;
 	struct ufs_clk_info *clki;
+	int len = 0;
+	size_t sz = 0;
 
 	if (!np)
 		goto out;
@@ -82,39 +84,59 @@ static int ufshcd_parse_clock_info(struct ufs_hba *hba)
 	if (cnt <= 0)
 		goto out;
 
-	clkfreq = kzalloc(cnt * sizeof(*clkfreq), GFP_KERNEL);
+	if (!of_get_property(np, "freq-table-hz", &len)) {
+		dev_info(dev, "freq-table-hz property not specified\n");
+		goto out;
+	}
+
+	if (len <= 0)
+		goto out;
+
+	sz = len / sizeof(*clkfreq);
+	if (sz != 2 * cnt) {
+		dev_err(dev, "%s len mismatch\n", "freq-table-hz");
+		ret = -EINVAL;
+		goto out;
+	}
+
+	clkfreq = devm_kzalloc(dev, sz * sizeof(*clkfreq),
+			GFP_KERNEL);
 	if (!clkfreq) {
+		dev_err(dev, "%s: no memory\n", "freq-table-hz");
 		ret = -ENOMEM;
-		dev_err(dev, "%s: memory alloc failed\n", __func__);
 		goto out;
 	}
 
-	ret = of_property_read_u32_array(np,
-			"max-clock-frequency-hz", clkfreq, cnt);
+	ret = of_property_read_u32_array(np, "freq-table-hz",
+			clkfreq, sz);
 	if (ret && (ret != -EINVAL)) {
-		dev_err(dev, "%s: invalid max-clock-frequency-hz property, %d\n",
-				__func__, ret);
-		goto out;
+		dev_err(dev, "%s: error reading array %d\n",
+				"freq-table-hz", ret);
+		goto free_clkfreq;
 	}
 
-	for (i = 0; i < cnt; i++) {
+	for (i = 0; i < sz; i += 2) {
 		ret = of_property_read_string_index(np,
-				"clock-names", i, (const char **)&name);
+				"clock-names", i/2, (const char **)&name);
 		if (ret)
-			goto out;
+			goto free_clkfreq;
 
 		clki = devm_kzalloc(dev, sizeof(*clki), GFP_KERNEL);
 		if (!clki) {
 			ret = -ENOMEM;
-			goto out;
+			goto free_clkfreq;
 		}
 
-		clki->max_freq = clkfreq[i];
+		clki->min_freq = clkfreq[i];
+		clki->max_freq = clkfreq[i+1];
 		clki->name = kstrdup(name, GFP_KERNEL);
+		dev_dbg(dev, "%s: min %u max %u name %s\n", "freq-table-hz",
+				clki->min_freq, clki->max_freq, clki->name);
 		list_add_tail(&clki->list, &hba->clk_list_head);
 	}
-out:
+free_clkfreq:
 	kfree(clkfreq);
+out:
 	return ret;
 }
 
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index 93c7c82..2caa27e 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -209,6 +209,7 @@ struct ufs_dev_cmd {
  * @clk: clock node
  * @name: clock name
  * @max_freq: maximum frequency supported by the clock
+ * @min_freq: min frequency that can be used for clock scaling
  * @enabled: variable to check against multiple enable/disable
  */
 struct ufs_clk_info {
@@ -216,6 +217,7 @@ struct ufs_clk_info {
 	struct clk *clk;
 	const char *name;
 	u32 max_freq;
+	u32 min_freq;
 	bool enabled;
 };
 
-- 
1.8.5.2
-- 
QUALCOMM ISRAEL, on behalf of Qualcomm Innovation Center, Inc. is a member
of Code Aurora Forum, hosted by The Linux Foundation

[PATCH/RFC V2 14/16] scsi: ufs: Add support for clock scaling using devfreq framework

[Dolev Raviv]

From: Sahitya Tummala <stummala@codeaurora.org>

The clocks for UFS device will be managed by generic DVFS (Dynamic
Voltage and Frequency Scaling) framework within kernel. This devfreq
framework works with different governors to scale the clocks. By default,
UFS devices uses simple_ondemand governor which scales the clocks up if
the load is more than upthreshold and scales down if the load is less than
downthreshold.

Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>

diff --git a/drivers/scsi/ufs/Kconfig b/drivers/scsi/ufs/Kconfig
index f07f901..6e07b2a 100644
--- a/drivers/scsi/ufs/Kconfig
+++ b/drivers/scsi/ufs/Kconfig
@@ -35,6 +35,8 @@
 config SCSI_UFSHCD
 	tristate "Universal Flash Storage Controller Driver Core"
 	depends on SCSI && SCSI_DMA
+	select PM_DEVFREQ
+	select DEVFREQ_GOV_SIMPLE_ONDEMAND
 	---help---
 	This selects the support for UFS devices in Linux, say Y and make
 	  sure that you know the name of your UFS host adapter (the card
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 1e5219c..6b769d0 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -38,6 +38,7 @@
  */
 
 #include <linux/async.h>
+#include <linux/devfreq.h>
 
 #include "ufshcd.h"
 #include "unipro.h"
@@ -536,6 +537,8 @@ static void ufshcd_ungate_work(struct work_struct *work)
 		hba->clk_gating.is_suspended = false;
 	}
 unblock_reqs:
+	if (ufshcd_is_clkscaling_enabled(hba))
+		devfreq_resume_device(hba->devfreq);
 	scsi_unblock_requests(hba->host);
 }
 
@@ -552,10 +555,10 @@ int ufshcd_hold(struct ufs_hba *hba, bool async)
 
 	if (!ufshcd_is_clkgating_allowed(hba))
 		goto out;
-start:
 	spin_lock_irqsave(hba->host->host_lock, flags);
 	hba->clk_gating.active_reqs++;
 
+start:
 	switch (hba->clk_gating.state) {
 	case CLKS_ON:
 		break;
@@ -586,6 +589,7 @@ start:
 			spin_unlock_irqrestore(hba->host->host_lock, flags);
 			flush_work(&hba->clk_gating.ungate_work);
 			/* Make sure state is CLKS_ON before returning */
+			spin_lock_irqsave(hba->host->host_lock, flags);
 			goto start;
 		}
 	default:
@@ -627,6 +631,11 @@ static void ufshcd_gate_work(struct work_struct *work)
 		ufshcd_set_link_hibern8(hba);
 	}
 
+	if (ufshcd_is_clkscaling_enabled(hba)) {
+		devfreq_suspend_device(hba->devfreq);
+		hba->clk_scaling.window_start_t = 0;
+	}
+
 	if (!ufshcd_is_link_active(hba))
 		ufshcd_setup_clocks(hba, false);
 	else
@@ -728,6 +737,32 @@ static void ufshcd_exit_clk_gating(struct ufs_hba *hba)
 	device_remove_file(hba->dev, &hba->clk_gating.delay_attr);
 }
 
+/* Must be called with host lock acquired */
+static void ufshcd_clk_scaling_start_busy(struct ufs_hba *hba)
+{
+	if (!ufshcd_is_clkscaling_enabled(hba))
+		return;
+
+	if (!hba->clk_scaling.is_busy_started) {
+		hba->clk_scaling.busy_start_t = ktime_get();
+		hba->clk_scaling.is_busy_started = true;
+	}
+}
+
+static void ufshcd_clk_scaling_update_busy(struct ufs_hba *hba)
+{
+	struct ufs_clk_scaling *scaling = &hba->clk_scaling;
+
+	if (!ufshcd_is_clkscaling_enabled(hba))
+		return;
+
+	if (!hba->outstanding_reqs && scaling->is_busy_started) {
+		scaling->tot_busy_t += ktime_to_us(ktime_sub(ktime_get(),
+					scaling->busy_start_t));
+		scaling->busy_start_t = ktime_set(0, 0);
+		scaling->is_busy_started = false;
+	}
+}
 /**
  * ufshcd_send_command - Send SCSI or device management commands
  * @hba: per adapter instance
@@ -736,6 +771,7 @@ static void ufshcd_exit_clk_gating(struct ufs_hba *hba)
 static inline
 void ufshcd_send_command(struct ufs_hba *hba, unsigned int task_tag)
 {
+	ufshcd_clk_scaling_start_busy(hba);
 	__set_bit(task_tag, &hba->outstanding_reqs);
 	ufshcd_writel(hba, 1 << task_tag, REG_UTP_TRANSFER_REQ_DOOR_BELL);
 }
@@ -2990,6 +3026,8 @@ static void ufshcd_transfer_req_compl(struct ufs_hba *hba)
 	/* clear corresponding bits of completed commands */
 	hba->outstanding_reqs ^= completed_reqs;
 
+	ufshcd_clk_scaling_update_busy(hba);
+
 	/* we might have free'd some tags above */
 	wake_up(&hba->dev_cmd.tag_wq);
 }
@@ -4021,6 +4059,10 @@ static int ufshcd_probe_hba(struct ufs_hba *hba)
 	if (!hba->is_init_prefetch)
 		hba->is_init_prefetch = true;
 
+	/* Resume devfreq after UFS device is detected */
+	if (ufshcd_is_clkscaling_enabled(hba))
+		devfreq_resume_device(hba->devfreq);
+
 out:
 	/*
 	 * If we failed to initialize the device or the device is not
@@ -4322,6 +4364,7 @@ static int ufshcd_init_clocks(struct ufs_hba *hba)
 					clki->max_freq, ret);
 				goto out;
 			}
+			clki->curr_freq = clki->max_freq;
 		}
 		dev_dbg(dev, "%s: clk: %s, rate: %lu\n", __func__,
 				clki->name, clk_get_rate(clki->clk));
@@ -4688,6 +4731,15 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 
 disable_clks:
 	/*
+	 * The clock scaling needs access to controller registers. Hence, Wait
+	 * for pending clock scaling work to be done before clocks are
+	 * turned off.
+	 */
+	if (ufshcd_is_clkscaling_enabled(hba)) {
+		devfreq_suspend_device(hba->devfreq);
+		hba->clk_scaling.window_start_t = 0;
+	}
+	/*
 	 * Call vendor specific suspend callback. As these callbacks may access
 	 * vendor specific host controller register space call them before the
 	 * host clocks are ON.
@@ -4716,6 +4768,7 @@ disable_clks:
 	 * host controller trasanction expected till resume.
 	 */
 	ufshcd_disable_irq(hba);
+
 	goto out;
 
 vops_resume:
@@ -4803,6 +4856,9 @@ static int ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 	ufshcd_disable_auto_bkops(hba);
 	hba->clk_gating.is_suspended = false;
 
+	if (ufshcd_is_clkscaling_enabled(hba))
+		devfreq_resume_device(hba->devfreq);
+
 	/* Schedule clock gating in case of no access to UFS device yet */
 	ufshcd_release(hba);
 	goto out;
@@ -4985,6 +5041,8 @@ void ufshcd_remove(struct ufs_hba *hba)
 	scsi_host_put(hba->host);
 
 	ufshcd_exit_clk_gating(hba);
+	if (ufshcd_is_clkscaling_enabled(hba))
+		devfreq_remove_device(hba->devfreq);
 	ufshcd_hba_exit(hba);
 }
 EXPORT_SYMBOL_GPL(ufshcd_remove);
@@ -5041,6 +5099,112 @@ out_error:
 }
 EXPORT_SYMBOL(ufshcd_alloc_host);
 
+static int ufshcd_scale_clks(struct ufs_hba *hba, bool scale_up)
+{
+	int ret = 0;
+	struct ufs_clk_info *clki;
+	struct list_head *head = &hba->clk_list_head;
+
+	if (!head || list_empty(head))
+		goto out;
+
+	list_for_each_entry(clki, head, list) {
+		if (!IS_ERR_OR_NULL(clki->clk)) {
+			if (scale_up && clki->max_freq) {
+				if (clki->curr_freq == clki->max_freq)
+					continue;
+				ret = clk_set_rate(clki->clk, clki->max_freq);
+				if (ret) {
+					dev_err(hba->dev, "%s: %s clk set rate(%dHz) failed, %d\n",
+						__func__, clki->name,
+						clki->max_freq, ret);
+					break;
+				}
+				clki->curr_freq = clki->max_freq;
+
+			} else if (!scale_up && clki->min_freq) {
+				if (clki->curr_freq == clki->min_freq)
+					continue;
+				ret = clk_set_rate(clki->clk, clki->min_freq);
+				if (ret) {
+					dev_err(hba->dev, "%s: %s clk set rate(%dHz) failed, %d\n",
+						__func__, clki->name,
+						clki->min_freq, ret);
+					break;
+				}
+				clki->curr_freq = clki->min_freq;
+			}
+		}
+		dev_dbg(hba->dev, "%s: clk: %s, rate: %lu\n", __func__,
+				clki->name, clk_get_rate(clki->clk));
+	}
+	if (hba->vops->clk_scale_notify)
+		hba->vops->clk_scale_notify(hba);
+out:
+	return ret;
+}
+
+static int ufshcd_devfreq_target(struct device *dev,
+				unsigned long *freq, u32 flags)
+{
+	int err = 0;
+	struct ufs_hba *hba = dev_get_drvdata(dev);
+
+	if (!ufshcd_is_clkscaling_enabled(hba))
+		return -EINVAL;
+
+	if (*freq == UINT_MAX)
+		err = ufshcd_scale_clks(hba, true);
+	else if (*freq == 0)
+		err = ufshcd_scale_clks(hba, false);
+
+	return err;
+}
+
+static int ufshcd_devfreq_get_dev_status(struct device *dev,
+		struct devfreq_dev_status *stat)
+{
+	struct ufs_hba *hba = dev_get_drvdata(dev);
+	struct ufs_clk_scaling *scaling = &hba->clk_scaling;
+	unsigned long flags;
+
+	if (!ufshcd_is_clkscaling_enabled(hba))
+		return -EINVAL;
+
+	memset(stat, 0, sizeof(*stat));
+
+	spin_lock_irqsave(hba->host->host_lock, flags);
+	if (!scaling->window_start_t)
+		goto start_window;
+
+	if (scaling->is_busy_started)
+		scaling->tot_busy_t += ktime_to_us(ktime_sub(ktime_get(),
+					scaling->busy_start_t));
+
+	stat->total_time = jiffies_to_usecs((long)jiffies -
+				(long)scaling->window_start_t);
+	stat->busy_time = scaling->tot_busy_t;
+start_window:
+	scaling->window_start_t = jiffies;
+	scaling->tot_busy_t = 0;
+
+	if (hba->outstanding_reqs) {
+		scaling->busy_start_t = ktime_get();
+		scaling->is_busy_started = true;
+	} else {
+		scaling->busy_start_t = ktime_set(0, 0);
+		scaling->is_busy_started = false;
+	}
+	spin_unlock_irqrestore(hba->host->host_lock, flags);
+	return 0;
+}
+
+static struct devfreq_dev_profile ufs_devfreq_profile = {
+	.polling_ms	= 100,
+	.target		= ufshcd_devfreq_target,
+	.get_dev_status	= ufshcd_devfreq_get_dev_status,
+};
+
 /**
  * ufshcd_init - Driver initialization routine
  * @hba: per-adapter instance
@@ -5151,6 +5315,19 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq)
 		goto out_remove_scsi_host;
 	}
 
+	if (ufshcd_is_clkscaling_enabled(hba)) {
+		hba->devfreq = devfreq_add_device(dev, &ufs_devfreq_profile,
+						   "simple_ondemand", NULL);
+		if (IS_ERR(hba->devfreq)) {
+			dev_err(hba->dev, "Unable to register with devfreq %ld\n",
+					PTR_ERR(hba->devfreq));
+			goto out_remove_scsi_host;
+		}
+		/* Suspend devfreq until the UFS device is detected */
+		devfreq_suspend_device(hba->devfreq);
+		hba->clk_scaling.window_start_t = 0;
+	}
+
 	/* Hold auto suspend until async scan completes */
 	pm_runtime_get_sync(dev);
 
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index 2caa27e..d5699d0 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -210,6 +210,7 @@ struct ufs_dev_cmd {
  * @name: clock name
  * @max_freq: maximum frequency supported by the clock
  * @min_freq: min frequency that can be used for clock scaling
+ * @curr_freq: indicates the current frequency that it is set to
  * @enabled: variable to check against multiple enable/disable
  */
 struct ufs_clk_info {
@@ -218,6 +219,7 @@ struct ufs_clk_info {
 	const char *name;
 	u32 max_freq;
 	u32 min_freq;
+	u32 curr_freq;
 	bool enabled;
 };
 
@@ -244,6 +246,7 @@ struct ufs_pwr_mode_info {
  * @name: variant name
  * @init: called when the driver is initialized
  * @exit: called to cleanup everything done in init
+ * @clk_scale_notify: notifies that clks are scaled up/down
  * @setup_clocks: called before touching any of the controller registers
  * @setup_regulators: called before accessing the host controller
  * @hce_enable_notify: called before and after HCE enable bit is set to allow
@@ -260,6 +263,7 @@ struct ufs_hba_variant_ops {
 	const char *name;
 	int	(*init)(struct ufs_hba *);
 	void    (*exit)(struct ufs_hba *);
+	void    (*clk_scale_notify)(struct ufs_hba *);
 	int     (*setup_clocks)(struct ufs_hba *, bool);
 	int     (*setup_regulators)(struct ufs_hba *, bool);
 	int     (*hce_enable_notify)(struct ufs_hba *, bool);
@@ -303,6 +307,13 @@ struct ufs_clk_gating {
 	int active_reqs;
 };
 
+struct ufs_clk_scaling {
+	ktime_t  busy_start_t;
+	bool is_busy_started;
+	unsigned long  tot_busy_t;
+	unsigned long window_start_t;
+};
+
 /**
  * struct ufs_init_prefetch - contains data that is pre-fetched once during
  * initialization
@@ -453,6 +464,11 @@ struct ufs_hba {
 #define UFSHCD_CAP_CLK_GATING	(1 << 0)
 	/* Allow hiberb8 with clk gating */
 #define UFSHCD_CAP_HIBERN8_WITH_CLK_GATING (1 << 1)
+	/* Allow dynamic clk scaling */
+#define UFSHCD_CAP_CLK_SCALING	(1 << 2)
+
+	struct devfreq *devfreq;
+	struct ufs_clk_scaling clk_scaling;
 };
 
 /* Returns true if clocks can be gated. Otherwise false */
@@ -464,6 +480,10 @@ static inline bool ufshcd_can_hibern8_during_gating(struct ufs_hba *hba)
 {
 	return hba->caps & UFSHCD_CAP_HIBERN8_WITH_CLK_GATING;
 }
+static inline int ufshcd_is_clkscaling_enabled(struct ufs_hba *hba)
+{
+	return hba->caps & UFSHCD_CAP_CLK_SCALING;
+}
 #define ufshcd_writel(hba, val, reg)	\
 	writel((val), (hba)->mmio_base + (reg))
 #define ufshcd_readl(hba, reg)	\
-- 
1.8.5.2
-- 
QUALCOMM ISRAEL, on behalf of Qualcomm Innovation Center, Inc. is a member
of Code Aurora Forum, hosted by The Linux Foundation

[PATCH/RFC V2 15/16] scsi: ufs: add capability to control the auto bkops during suspend

[Dolev Raviv]

From: Subhash Jadavani <subhashj@codeaurora.org>

If host explicitly enables the auto bkops (background operation) on device
then only device would perform the bkops on its own. If auto bkops is not
enabled explicitly and if the device reaches to state where it must do
background operation, device would raise the urgent bkops exception event
to host and then host will enable the auto bkops on device. This patch
adds the option to choose whether auto bkops should be enabled during
runtime suspend or not.

Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 6b769d0..d9eb2da 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -4704,13 +4704,18 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 	}
 
 	if (ufshcd_is_runtime_pm(pm_op)) {
-		/*
-		 * The device is idle with no requests in the queue,
-		 * allow background operations if needed.
-		 */
-		ret = ufshcd_bkops_ctrl(hba, BKOPS_STATUS_NON_CRITICAL);
-		if (ret)
-			goto enable_gating;
+		if (ufshcd_can_autobkops_during_suspend(hba)) {
+			/*
+			 * The device is idle with no requests in the queue,
+			 * allow background operations if needed.
+			 */
+			ret = ufshcd_bkops_ctrl(hba, BKOPS_STATUS_NON_CRITICAL);
+			if (ret)
+				goto enable_gating;
+		} else {
+			/* make sure that auto bkops is disabled */
+			ufshcd_disable_auto_bkops(hba);
+		}
 	}
 
 	if ((req_dev_pwr_mode != hba->curr_dev_pwr_mode) &&
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index d5699d0..b94b835 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -466,6 +466,8 @@ struct ufs_hba {
 #define UFSHCD_CAP_HIBERN8_WITH_CLK_GATING (1 << 1)
 	/* Allow dynamic clk scaling */
 #define UFSHCD_CAP_CLK_SCALING	(1 << 2)
+	/* Allow auto bkops to enabled during runtime suspend */
+#define UFSHCD_CAP_AUTO_BKOPS_SUSPEND (1 << 3)
 
 	struct devfreq *devfreq;
 	struct ufs_clk_scaling clk_scaling;
@@ -484,6 +486,11 @@ static inline int ufshcd_is_clkscaling_enabled(struct ufs_hba *hba)
 {
 	return hba->caps & UFSHCD_CAP_CLK_SCALING;
 }
+static inline bool ufshcd_can_autobkops_during_suspend(struct ufs_hba *hba)
+{
+	return hba->caps & UFSHCD_CAP_AUTO_BKOPS_SUSPEND;
+}
+
 #define ufshcd_writel(hba, val, reg)	\
 	writel((val), (hba)->mmio_base + (reg))
 #define ufshcd_readl(hba, reg)	\
-- 
1.8.5.2
-- 
QUALCOMM ISRAEL, on behalf of Qualcomm Innovation Center, Inc. is a member
of Code Aurora Forum, hosted by The Linux Foundation

[PATCH/RFC V2 16/16] scsi: ufs: definitions for phy interface

[Dolev Raviv]

- Adding some of the definitions missing in unipro.h, including power
  enumeration.
- Read Modify Write Line helper function
- Indication for the type of suspend

Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Yaniv Gardi <ygardi@codeaurora.org>

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index d9eb2da..1b04cfa 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -4924,6 +4924,8 @@ int ufshcd_system_suspend(struct ufs_hba *hba)
 
 	ret = ufshcd_suspend(hba, UFS_SYSTEM_PM);
 out:
+	if (!ret)
+		hba->is_sys_suspended = true;
 	return ret;
 }
 EXPORT_SYMBOL(ufshcd_system_suspend);
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index b94b835..d502d70 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -471,6 +471,7 @@ struct ufs_hba {
 
 	struct devfreq *devfreq;
 	struct ufs_clk_scaling clk_scaling;
+	bool is_sys_suspended;
 };
 
 /* Returns true if clocks can be gated. Otherwise false */
@@ -496,6 +497,23 @@ static inline bool ufshcd_can_autobkops_during_suspend(struct ufs_hba *hba)
 #define ufshcd_readl(hba, reg)	\
 	readl((hba)->mmio_base + (reg))
 
+/**
+ * ufshcd_rmwl - read modify write into a register
+ * @hba - per adapter instance
+ * @mask - mask to apply on read value
+ * @val - actual value to write
+ * @reg - register address
+ */
+static inline void ufshcd_rmwl(struct ufs_hba *hba, u32 mask, u32 val, u32 reg)
+{
+	u32 tmp;
+
+	tmp = ufshcd_readl(hba, reg);
+	tmp &= ~mask;
+	tmp |= (val & mask);
+	ufshcd_writel(hba, tmp, reg);
+}
+
 int ufshcd_alloc_host(struct device *, struct ufs_hba **);
 int ufshcd_init(struct ufs_hba * , void __iomem * , unsigned int);
 void ufshcd_remove(struct ufs_hba *);
diff --git a/drivers/scsi/ufs/unipro.h b/drivers/scsi/ufs/unipro.h
index 0bb8041..3fc3e21 100644
--- a/drivers/scsi/ufs/unipro.h
+++ b/drivers/scsi/ufs/unipro.h
@@ -13,6 +13,44 @@
 #define _UNIPRO_H_
 
 /*
+ * M-TX Configuration Attributes
+ */
+#define TX_MODE					0x0021
+#define TX_HSRATE_SERIES			0x0022
+#define TX_HSGEAR				0x0023
+#define TX_PWMGEAR				0x0024
+#define TX_AMPLITUDE				0x0025
+#define TX_HS_SLEWRATE				0x0026
+#define TX_SYNC_SOURCE				0x0027
+#define TX_HS_SYNC_LENGTH			0x0028
+#define TX_HS_PREPARE_LENGTH			0x0029
+#define TX_LS_PREPARE_LENGTH			0x002A
+#define TX_HIBERN8_CONTROL			0x002B
+#define TX_LCC_ENABLE				0x002C
+#define TX_PWM_BURST_CLOSURE_EXTENSION		0x002D
+#define TX_BYPASS_8B10B_ENABLE			0x002E
+#define TX_DRIVER_POLARITY			0x002F
+#define TX_HS_UNTERMINATED_LINE_DRIVE_ENABLE	0x0030
+#define TX_LS_TERMINATED_LINE_DRIVE_ENABLE	0x0031
+#define TX_LCC_SEQUENCER			0x0032
+#define TX_MIN_ACTIVATETIME			0x0033
+#define TX_PWM_G6_G7_SYNC_LENGTH		0x0034
+
+/*
+ * M-RX Configuration Attributes
+ */
+#define RX_MODE					0x00A1
+#define RX_HSRATE_SERIES			0x00A2
+#define RX_HSGEAR				0x00A3
+#define RX_PWMGEAR				0x00A4
+#define RX_LS_TERMINATED_ENABLE			0x00A5
+#define RX_HS_UNTERMINATED_ENABLE		0x00A6
+#define RX_ENTER_HIBERN8			0x00A7
+#define RX_BYPASS_8B10B_ENABLE			0x00A8
+#define RX_TERMINATION_FORCE_ENABLE		0x0089
+
+#define is_mphy_tx_attr(attr)			(attr < RX_MODE)
+/*
  * PHY Adpater attributes
  */
 #define PA_ACTIVETXDATALANES	0x1560
@@ -87,6 +125,24 @@ enum {
 	PA_HS_MODE_B	= 2,
 };
 
+enum ufs_pwm_gear_tag {
+	UFS_PWM_DONT_CHANGE,	/* Don't change Gear */
+	UFS_PWM_G1,		/* PWM Gear 1 (default for reset) */
+	UFS_PWM_G2,		/* PWM Gear 2 */
+	UFS_PWM_G3,		/* PWM Gear 3 */
+	UFS_PWM_G4,		/* PWM Gear 4 */
+	UFS_PWM_G5,		/* PWM Gear 5 */
+	UFS_PWM_G6,		/* PWM Gear 6 */
+	UFS_PWM_G7,		/* PWM Gear 7 */
+};
+
+enum ufs_hs_gear_tag {
+	UFS_HS_DONT_CHANGE,	/* Don't change Gear */
+	UFS_HS_G1,		/* HS Gear 1 (default for reset) */
+	UFS_HS_G2,		/* HS Gear 2 */
+	UFS_HS_G3,		/* HS Gear 3 */
+};
+
 /*
  * Data Link Layer Attributes
  */
-- 
1.8.5.2
-- 
QUALCOMM ISRAEL, on behalf of Qualcomm Innovation Center, Inc. is a member
of Code Aurora Forum, hosted by The Linux Foundation

Re: [PATCH/RFC V2 07/16] scsi: support well known logical units

[subhashj]

> On Thu, Aug 14, 2014 at 04:30:58PM +0300, Dolev Raviv wrote:
>> From: Subhash Jadavani <subhashj@codeaurora.org>
>> REPORT LUNS command has "SELECT REPORT" field which controls what type of
>> logical units to be reported by device server. According to UFS device
standard, if this field is set to 0, REPORT LUNS would report only
report
>> standard logical units. If it's set to 1 then it would report only well
known logical unit and if it's set to 2 then device would report both
standard and well known logical units.
>> Some well-known logical units might not have scsi upper-layer drivers. In
>> such cases, the runtime PM reference count increased during device
enumeration will not be decreased, causing the parent device (host) to
always be on even during idle.
>> This change allows the SCSI LLD (Low Level Driver) to choose which type
of logical units should be detected.
>> Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
>> Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
>> Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
>> diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c index
4a6e4ba..5a0e164 100644
>> --- a/drivers/scsi/scsi_scan.c
>> +++ b/drivers/scsi/scsi_scan.c
>> @@ -802,6 +802,14 @@ static int scsi_add_lun(struct scsi_device *sdev,
unsigned char *inq_result,
>>  	} else {
>>  		sdev->type = (inq_result[0] & 0x1f);
>>  		sdev->removable = (inq_result[1] & 0x80) >> 7;
>> +
>> +		/*
>> +		 * some devices may respond with wrong type for
>> +		 * well-known logical units. Force well-known type
>> +		 * to enumerate them correctly.
>> +		 */
>> +		if (scsi_is_wlun(sdev->lun) && (sdev->type != TYPE_WLUN))
>> +			sdev->type = TYPE_WLUN;
> no need to test for TYPE_WLUN here.]

Agreed, will fix it.

>>  	switch (sdev->type) {
>> @@ -817,6 +825,7 @@ static int scsi_add_lun(struct scsi_device *sdev,
unsigned char *inq_result,
>>  	case TYPE_COMM:
>>  	case TYPE_RAID:
>>  	case TYPE_OSD:
>> +	case TYPE_WLUN:
>>  		sdev->writeable = 1;
>>  		break;
>>  	case TYPE_ROM:
> This switch statements has been removed in 3.17-rc1, please rebase your
series on top of it.

Sure.

> While you're at it please make this patch, which
> introduceѕ core scsi changes first in the series.

Ok. Will move these core changes first in the current patch series.

>> @@ -1412,6 +1421,13 @@ static int scsi_report_lun_scan(struct
>> scsi_target *starget, int bflags,
>>  	 */
>>  	memset(&scsi_cmd[1], 0, 5);
>> +	if (shost->report_wlus)
>> +		/*
>> +		 * Set "SELECT REPORT" field to 0x2 which will make device to +		 *
report well known logical units along with standard LUs.
>> +		 */
>> +		scsi_cmd[2] = 0x2;
> So we're finally getting well known LUN support.  I think we should key
this
> off the SBC compliance level and not have the drivers opt in.

If i understood this correctly, we want to make all devices report well
known LUs irrespective of device driver (LLD)'s preference? If yes then i
will knock off "if (shost->report_wlus)" check.

>> diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c
index 5f36788..ba9d0f0 100644
>> --- a/drivers/scsi/scsi_sysfs.c
>> +++ b/drivers/scsi/scsi_sysfs.c
>> @@ -1060,6 +1060,13 @@ int scsi_sysfs_add_sdev(struct scsi_device
*sdev)
>>  		}
>>  	}
>> +	/*
>> +	 * put runtime pm reference for well-known logical units,
>> +	 * drivers are expected to _get_* again during probe.
>> +	 */
>> +	if (scsi_is_wlun(sdev->lun))
>> +		scsi_autopm_put_device(sdev);
> Special casing the well known LUNs here seems wrong.  Shouldn't we do
this
> for any devices that don't get a driver attached to them?

Agreed, i will replace "if (scsi_is_wlun(sdev->lun))" check with "if
(sdev->sdev_gendev.driver)".

Regards,
Subhash

Re: [PATCH/RFC V2 07/16] scsi: support well known logical units

[Christoph Hellwig]

On Fri, Aug 22, 2014 at 12:02:30AM -0000, subhashj@codeaurora.org wrote:
> >> +	/*
> >> +	 * put runtime pm reference for well-known logical units,
> >> +	 * drivers are expected to _get_* again during probe.
> >> +	 */
> >> +	if (scsi_is_wlun(sdev->lun))
> >> +		scsi_autopm_put_device(sdev);
> > Special casing the well known LUNs here seems wrong.  Shouldn't we do
> this
> > for any devices that don't get a driver attached to them?
> 
> Agreed, i will replace "if (scsi_is_wlun(sdev->lun))" check with "if
> (sdev->sdev_gendev.driver)".

I would really prefer the callers of autopm get/put to be symmetric to
issues with later than probe driver attach or similar.  Think of the
case say the CDROM or tape driver only gets loaded after we already
did a bus scan.  A quick check of the autopm code and it's underlying
implementation seems to suggest that nesting them is okay.  If that's
indeed the case I would suggest to restructure it the following way:

 - make the scsi_autopm_put_device call you add at the end of
   scsi_sysfs_add_sdev unconditional to make it balance out
   the get earlier in the function (and delete the now incorrect comment
   above the scsi_autopm_get_device call).
 - let drivers do paired get/put calls in their probe/remove methods.

If you still need any wlun changes after that please send them as a
separate patch with a detailed description on why you need it.

All in all the autopm code and it's underlying implementation is highly
confusing, so additional documentation on it would also be very welcome.

Re: [PATCH/RFC V2 07/16] scsi: support well known logical units

[subhashj]

> On Fri, Aug 22, 2014 at 12:02:30AM -0000, subhashj@codeaurora.org wrote:
>> >> +	/*
>> >> +	 * put runtime pm reference for well-known logical units,
>> >> +	 * drivers are expected to _get_* again during probe.
>> >> +	 */
>> >> +	if (scsi_is_wlun(sdev->lun))
>> >> +		scsi_autopm_put_device(sdev);
>> > Special casing the well known LUNs here seems wrong.  Shouldn't we do
>> this
>> > for any devices that don't get a driver attached to them?
>>
>> Agreed, i will replace "if (scsi_is_wlun(sdev->lun))" check with "if
>> (sdev->sdev_gendev.driver)".
>
> I would really prefer the callers of autopm get/put to be symmetric to
> issues with later than probe driver attach or similar.  Think of the
> case say the CDROM or tape driver only gets loaded after we already
> did a bus scan.  A quick check of the autopm code and it's underlying
> implementation seems to suggest that nesting them is okay.  If that's
> indeed the case I would suggest to restructure it the following way:
>
>  - make the scsi_autopm_put_device call you add at the end of
>    scsi_sysfs_add_sdev unconditional to make it balance out
>    the get earlier in the function (and delete the now incorrect comment
>    above the scsi_autopm_get_device call).
>  - let drivers do paired get/put calls in their probe/remove methods.
>
> If you still need any wlun changes after that please send them as a
> separate patch with a detailed description on why you need it.

Thanks, yes I was also thinking on same lines but was not sure if it would
work or not. But let me check this more and if it works, will make a
different patch for it.

> All in all the autopm code and it's underlying implementation is highly
> confusing, so additional documentation on it would also be very welcome.

I would agree but not sure if I would be able to add it now, hopefully
some time in future.
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