[PATCH RFC v3] mmc: sdhci-msm: Add support for MSM chipsets

[Georgi Djakov <gdjakov@mm-sol.com>]

This platform driver adds the support of Secure Digital Host
Controller Interface compliant controller in MSM chipsets.

CC: Asutosh Das <asutoshd@codeaurora.org>
CC: Venkat Gopalakrishnan <venkatg@codeaurora.org>
CC: Sahitya Tummala <stummala@codeaurora.org>
CC: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Georgi Djakov <gdjakov@mm-sol.com>
---
Changes from v2:
- Added DT bindings for clocks
- Moved voltage regulators data to platform data
- Removed unneeded includes
- Removed obsolete and wrapper functions
- Removed error checking where unnecessary
- Removed redundant _clk suffix from clock names
- Just return instead of goto where possible
- Minor fixes

Changes from v1:
- GPIO references are replaced by pinctrl
- DT parsing is done mostly by mmc_of_parse()
- Use of_match_device() for DT matching
- A few minor changes

 .../devicetree/bindings/mmc/sdhci-msm.txt          |   71 ++
 drivers/mmc/host/Kconfig                           |   13 +
 drivers/mmc/host/Makefile                          |    1 +
 drivers/mmc/host/sdhci-msm.c                       |  687 ++++++++++++++++++++
 4 files changed, 772 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/mmc/sdhci-msm.txt
 create mode 100644 drivers/mmc/host/sdhci-msm.c

diff --git a/Documentation/devicetree/bindings/mmc/sdhci-msm.txt b/Documentation/devicetree/bindings/mmc/sdhci-msm.txt
new file mode 100644
index 0000000..ee112da
--- /dev/null
+++ b/Documentation/devicetree/bindings/mmc/sdhci-msm.txt
@@ -0,0 +1,71 @@
+* Qualcomm SDHCI controller (sdhci-msm)
+
+This file documents differences between the core properties in mmc.txt
+and the properties used by the sdhci-msm driver.
+
+Required properties:
+- compatible: should be "qcom,sdhci-msm"
+- reg: should contain SDHC, SD Core register map
+- reg-names: indicates various resources passed to driver (via reg proptery) by name
+	"reg-names" examples are "hc_mem" and "core_mem"
+- interrupts: should contain SDHC interrupts
+- interrupt-names: indicates interrupts passed to driver (via interrupts property) by name
+	"interrupt-names" examples are "hc_irq" and "pwr_irq"
+- <supply-name>-supply: phandle to the regulator device tree node
+	"supply-name" examples are "vdd" and "vdd-io"
+- pinctrl-names: Should contain only one value - "default".
+- pinctrl-0: Should specify pin control groups used for this controller.
+- clocks: phandles to clock instances of the device tree nodes
+- clock-names:
+	iface: Main peripheral bus clock (PCLK/HCLK - AHB Bus clock) (required)
+	core: SDC MMC clock (MCLK) (required)
+	bus: SDCC bus voter clock (optional)
+
+Optional properties:
+- qcom,bus-speed-mode - specifies supported bus speed modes by host
+	The supported bus speed modes are :
+	"HS200_1p8v" - indicates that host can support HS200 at 1.8v
+	"HS200_1p2v" - indicates that host can support HS200 at 1.2v
+	"DDR_1p8v" - indicates that host can support DDR mode at 1.8v
+	"DDR_1p2v" - indicates that host can support DDR mode at 1.2v
+
+In the following, <supply> can be vdd (flash core voltage) or vdd-io (I/O voltage).
+- qcom,<supply>-always-on - specifies whether supply should be kept "on" always.
+- qcom,<supply>-lpm-sup - specifies whether supply can be kept in low power mode (lpm).
+- qcom,<supply>-voltage-level - specifies voltage levels for supply. Should be
+specified in pairs (min, max), units uV.
+- qcom,<supply>-current-level - specifies load levels for supply in lpm or high power mode
+	(hpm). Should be specified in pairs (lpm, hpm), units uA.
+
+Example:
+
+	aliases {
+		sdhc1 = &sdhc_1;
+	};
+
+	sdhc_1: qcom,sdhc@f9824900 {
+		compatible = "qcom,sdhci-msm";
+		reg = <0xf9824900 0x11c>, <0xf9824000 0x800>;
+		reg-names = "hc_mem", "core_mem";
+		interrupts = <0 123 0>, <0 138 0>;
+		interrupt-names = "hc_irq", "pwr_irq";
+		bus-width = <4>;
+		non-removable;
+
+		vdd-supply = <&pm8941_l21>;
+		vdd-io-supply = <&pm8941_l13>;
+		qcom,vdd-voltage-level = <2950000 2950000>;
+		qcom,vdd-current-level = <9000 800000>;
+		qcom,vdd-io-always-on;
+		qcom,vdd-io-lpm-sup;
+		qcom,vdd-io-voltage-level = <1800000 2950000>;
+		qcom,vdd-io-current-level = <6 22000>;
+		qcom,bus-speed-mode = "HS200_1p8v", "DDR_1p8v";
+
+		pinctrl-names = "default";
+		pinctrl-0 = <&sdc1_clk &sdc1_cmd &sdc1_data>;
+
+		clocks = <&iface>, <&core>, <&bus>;
+		clock-names = "iface", "core", "bus";
+
+	};
diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
index 8a4c066..2b31471 100644
--- a/drivers/mmc/host/Kconfig
+++ b/drivers/mmc/host/Kconfig
@@ -322,6 +322,19 @@ config MMC_ATMELMCI
 
 	  If unsure, say N.
 
+config MMC_SDHCI_MSM
+	tristate "Qualcomm SDHCI Controller Support"
+	depends on ARCH_MSM
+	depends on MMC_SDHCI_PLTFM
+	help
+	  This selects the Secure Digital Host Controller Interface (SDHCI)
+	  support present in MSM SOCs from Qualcomm. The controller
+	  supports SD/MMC/SDIO devices.
+
+	  If you have a controller with this interface, say Y or M here.
+
+	  If unsure, say N.
+
 config MMC_MSM
 	tristate "Qualcomm SDCC Controller Support"
 	depends on MMC && ARCH_MSM
diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
index d422e21..efd6e6a 100644
--- a/drivers/mmc/host/Makefile
+++ b/drivers/mmc/host/Makefile
@@ -63,6 +63,7 @@ obj-$(CONFIG_MMC_SDHCI_OF_ESDHC)	+= sdhci-of-esdhc.o
 obj-$(CONFIG_MMC_SDHCI_OF_HLWD)		+= sdhci-of-hlwd.o
 obj-$(CONFIG_MMC_SDHCI_BCM_KONA)	+= sdhci-bcm-kona.o
 obj-$(CONFIG_MMC_SDHCI_BCM2835)		+= sdhci-bcm2835.o
+obj-$(CONFIG_MMC_SDHCI_MSM)		+= sdhci-msm.o
 
 ifeq ($(CONFIG_CB710_DEBUG),y)
 	CFLAGS-cb710-mmc	+= -DDEBUG
diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
new file mode 100644
index 0000000..b795286
--- /dev/null
+++ b/drivers/mmc/host/sdhci-msm.c
@@ -0,0 +1,687 @@
+/*
+ * drivers/mmc/host/sdhci-msm.c - Qualcomm MSM SDHCI Platform
+ * driver source file
+ *
+ * Copyright (c) 2013, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/regulator/consumer.h>
+
+#include "sdhci-pltfm.h"
+
+#define CORE_HC_MODE		0x78
+#define HC_MODE_EN		0x1
+
+#define CORE_POWER		0x0
+#define CORE_SW_RST		(1 << 7)
+
+#define CORE_PWRCTL_STATUS	0xdc
+#define CORE_PWRCTL_MASK	0xe0
+#define CORE_PWRCTL_CLEAR	0xe4
+#define CORE_PWRCTL_CTL		0xe8
+
+#define CORE_PWRCTL_BUS_OFF	0x01
+#define CORE_PWRCTL_BUS_ON	(1 << 1)
+#define CORE_PWRCTL_IO_LOW	(1 << 2)
+#define CORE_PWRCTL_IO_HIGH	(1 << 3)
+
+#define CORE_PWRCTL_BUS_SUCCESS	0x01
+#define CORE_PWRCTL_BUS_FAIL	(1 << 1)
+#define CORE_PWRCTL_IO_SUCCESS	(1 << 2)
+#define CORE_PWRCTL_IO_FAIL	(1 << 3)
+
+#define INT_MASK		0xf
+
+/* This structure keeps information per regulator */
+struct sdhci_msm_reg_data {
+	/* voltage regulator handle */
+	struct regulator *reg;
+	/* regulator name */
+	const char *name;
+	/* voltage level to be set */
+	u32 low_vol_level;
+	u32 high_vol_level;
+	/* Load values for low power and high power mode */
+	u32 lpm_uA;
+	u32 hpm_uA;
+
+	/* is this regulator needs to be always on? */
+	bool is_always_on;
+	/* is low power mode setting required for this regulator? */
+	bool lpm_sup;
+};
+
+struct sdhci_msm_pltfm_data {
+	/* Supported UHS-I Modes */
+	u32 caps;
+
+	/* More capabilities */
+	u32 caps2;
+
+	/* keeps VDD/VCC regulator info */
+	struct sdhci_msm_reg_data *vdd_data;
+	/* keeps VDD IO regulator info */
+	struct sdhci_msm_reg_data *vdd_io_data;
+};
+
+struct sdhci_msm_host {
+	struct platform_device	*pdev;
+	void __iomem *core_mem;	/* MSM SDCC mapped address */
+	int	pwr_irq;	/* power irq */
+	struct clk *clk;	/* main SD/MMC bus clock */
+	struct clk *pclk;	/* SDHC peripheral bus clock */
+	struct clk *bus_clk;	/* SDHC bus voter clock */
+	struct sdhci_msm_pltfm_data *pdata;
+	struct mmc_host *mmc;
+	struct sdhci_pltfm_data sdhci_msm_pdata;
+};
+
+enum vdd_io_level {
+	/* set vdd_io_data->low_vol_level */
+	VDD_IO_LOW,
+	/* set vdd_io_data->high_vol_level */
+	VDD_IO_HIGH,
+	/*
+	 * set whatever there in voltage_level (third argument) of
+	 * sdhci_msm_set_vdd_io_vol() function.
+	 */
+	VDD_IO_SET_LEVEL,
+};
+
+#define MAX_PROP_SIZE 32
+static int sdhci_msm_dt_parse_vreg_info(struct device *dev,
+					struct sdhci_msm_reg_data **vreg_data,
+					const char *vreg_name)
+{
+	int len, ret = 0;
+	const __be32 *prop;
+	char prop_name[MAX_PROP_SIZE];
+	struct sdhci_msm_reg_data *vreg;
+	struct device_node *np = dev->of_node;
+
+	snprintf(prop_name, MAX_PROP_SIZE, "%s-supply", vreg_name);
+	if (!of_parse_phandle(np, prop_name, 0)) {
+		dev_info(dev, "No vreg data found for %s\n", vreg_name);
+		ret = -EINVAL;
+		return ret;
+	}
+
+	vreg = devm_kzalloc(dev, sizeof(*vreg), GFP_KERNEL);
+	if (!vreg) {
+		dev_err(dev, "No memory for vreg: %s\n", vreg_name);
+		ret = -ENOMEM;
+		return ret;
+	}
+
+	vreg->name = vreg_name;
+
+	snprintf(prop_name, MAX_PROP_SIZE, "qcom,%s-always-on", vreg_name);
+	if (of_get_property(np, prop_name, NULL))
+		vreg->is_always_on = true;
+
+	snprintf(prop_name, MAX_PROP_SIZE, "qcom,%s-lpm-sup", vreg_name);
+	if (of_get_property(np, prop_name, NULL))
+		vreg->lpm_sup = true;
+
+	snprintf(prop_name, MAX_PROP_SIZE, "qcom,%s-voltage-level", vreg_name);
+	prop = of_get_property(np, prop_name, &len);
+	if (!prop || (len != (2 * sizeof(__be32)))) {
+		dev_warn(dev, "%s %s property\n",
+			 prop ? "invalid format" : "no", prop_name);
+	} else {
+		vreg->low_vol_level = be32_to_cpup(&prop[0]);
+		vreg->high_vol_level = be32_to_cpup(&prop[1]);
+	}
+
+	snprintf(prop_name, MAX_PROP_SIZE, "qcom,%s-current-level", vreg_name);
+	prop = of_get_property(np, prop_name, &len);
+	if (!prop || (len != (2 * sizeof(__be32)))) {
+		dev_warn(dev, "%s %s property\n",
+			 prop ? "invalid format" : "no", prop_name);
+	} else {
+		vreg->lpm_uA = be32_to_cpup(&prop[0]);
+		vreg->hpm_uA = be32_to_cpup(&prop[1]);
+	}
+
+	*vreg_data = vreg;
+	dev_dbg(dev, "%s: %s %s vol=[%d %d]uV, curr=[%d %d]uA\n",
+		vreg->name, vreg->is_always_on ? "always_on," : "",
+		vreg->lpm_sup ? "lpm_sup," : "", vreg->low_vol_level,
+		vreg->high_vol_level, vreg->lpm_uA, vreg->hpm_uA);
+
+	return ret;
+}
+
+/* Parse platform data */
+static struct sdhci_msm_pltfm_data *sdhci_msm_populate_pdata(struct device *dev)
+{
+	struct sdhci_msm_pltfm_data *pdata = NULL;
+	struct device_node *np = dev->of_node;
+	int len, i;
+
+	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
+	if (!pdata) {
+		dev_err(dev, "failed to allocate memory for platform data\n");
+		return NULL;
+	}
+
+	if (sdhci_msm_dt_parse_vreg_info(dev, &pdata->vdd_data, "vdd")) {
+		dev_err(dev, "failed parsing vdd data\n");
+		return NULL;
+	}
+	if (sdhci_msm_dt_parse_vreg_info(dev, &pdata->vdd_io_data, "vdd-io")) {
+		dev_err(dev, "failed parsing vdd-io data\n");
+		return NULL;
+	}
+
+	len = of_property_count_strings(np, "qcom,bus-speed-mode");
+
+	for (i = 0; i < len; i++) {
+		const char *name = NULL;
+
+		of_property_read_string_index(np,
+					      "qcom,bus-speed-mode", i, &name);
+		if (!name)
+			continue;
+
+		if (!strncmp(name, "HS200_1p8v", sizeof("HS200_1p8v")))
+			pdata->caps2 |= MMC_CAP2_HS200_1_8V_SDR;
+		else if (!strncmp(name, "HS200_1p2v", sizeof("HS200_1p2v")))
+			pdata->caps2 |= MMC_CAP2_HS200_1_2V_SDR;
+		else if (!strncmp(name, "DDR_1p8v", sizeof("DDR_1p8v")))
+			pdata->caps |= MMC_CAP_1_8V_DDR | MMC_CAP_UHS_DDR50;
+		else if (!strncmp(name, "DDR_1p2v", sizeof("DDR_1p2v")))
+			pdata->caps |= MMC_CAP_1_2V_DDR | MMC_CAP_UHS_DDR50;
+	}
+
+	return pdata;
+}
+
+/* Regulator utility functions */
+static int sdhci_msm_vreg_init_reg(struct device *dev,
+				   struct sdhci_msm_reg_data *vreg)
+{
+	int ret = 0;
+
+	/* check if regulator is already initialized? */
+	if (!IS_ERR(vreg->reg))
+		return ret;
+
+	/* Get the regulator handle */
+	vreg->reg = devm_regulator_get(dev, vreg->name);
+	if (IS_ERR(vreg->reg)) {
+		ret = PTR_ERR(vreg->reg);
+		dev_err(dev, "devm_regulator_get(%s) failed. ret=%d\n",
+			vreg->name, ret);
+		return ret;
+	}
+
+	/* sanity check */
+	if (!vreg->high_vol_level || !vreg->hpm_uA) {
+		dev_err(dev, "%s invalid constraints specified\n", vreg->name);
+		return -EINVAL;
+	}
+
+	return ret;
+}
+
+static int sdhci_msm_vreg_enable(struct sdhci_msm_reg_data *vreg)
+{
+	int ret = 0;
+
+	/* Put regulator in HPM (high power mode) */
+	ret = regulator_set_optimum_mode(vreg->reg, vreg->hpm_uA);
+	if (ret < 0) {
+		pr_err
+		    ("%s: regulator_set_optimum_mode(%s,uA_load=%d) fail(%d)\n",
+		     __func__, vreg->name, vreg->hpm_uA, ret);
+		return ret;
+	}
+
+	if (!regulator_is_enabled(vreg->reg)) {
+		/* Set voltage level */
+		ret = regulator_set_voltage(vreg->reg, vreg->high_vol_level,
+						 vreg->high_vol_level);
+		if (ret)
+			return ret;
+	}
+	ret = regulator_enable(vreg->reg);
+	if (ret) {
+		pr_err("%s: regulator_enable(%s) failed. ret=%d\n",
+		       __func__, vreg->name, ret);
+		return ret;
+	}
+	return ret;
+}
+
+static int sdhci_msm_vreg_disable(struct sdhci_msm_reg_data *vreg)
+{
+	int ret = 0;
+
+	/* Never disable regulator marked as always_on */
+	if (regulator_is_enabled(vreg->reg) && !vreg->is_always_on) {
+		ret = regulator_disable(vreg->reg);
+		if (ret) {
+			pr_err("%s: regulator_disable(%s) failed. ret=%d\n",
+			       __func__, vreg->name, ret);
+			return ret;
+		}
+
+		ret = regulator_set_optimum_mode(vreg->reg, 0);
+		if (ret < 0)
+			return ret;
+
+		/* Set min. voltage level to 0 */
+		ret = regulator_set_voltage(vreg->reg, 0, vreg->high_vol_level);
+		if (ret)
+			return ret;
+	} else if (regulator_is_enabled(vreg->reg) && vreg->is_always_on) {
+		if (vreg->lpm_sup) {
+			/* Put always_on regulator in LPM (low power mode) */
+			ret = regulator_set_optimum_mode(vreg->reg,
+					vreg->lpm_uA);
+			if (ret < 0)
+				return ret;
+		}
+	}
+
+	return ret;
+}
+
+static int sdhci_msm_setup_vreg(struct sdhci_msm_pltfm_data *pdata,
+				bool enable, bool is_init)
+{
+	int ret = 0, i;
+	struct sdhci_msm_reg_data *vreg_table[2];
+
+	vreg_table[0] = pdata->vdd_data;
+	vreg_table[1] = pdata->vdd_io_data;
+
+	for (i = 0; i < ARRAY_SIZE(vreg_table); i++) {
+		if (vreg_table[i]) {
+			if (enable)
+				ret = sdhci_msm_vreg_enable(vreg_table[i]);
+			else
+				ret = sdhci_msm_vreg_disable(vreg_table[i]);
+			if (ret)
+				return ret;
+		}
+	}
+	return ret;
+}
+
+/*
+ * Reset vreg by ensuring it is off during probe. A call
+ * to enable vreg is needed to balance disable vreg
+ */
+static int sdhci_msm_vreg_reset(struct sdhci_msm_pltfm_data *pdata)
+{
+	int ret;
+
+	ret = sdhci_msm_setup_vreg(pdata, 1, true);
+	if (ret)
+		return ret;
+	ret = sdhci_msm_setup_vreg(pdata, 0, true);
+	return ret;
+}
+
+/* This init function should be called only once for each SDHC slot */
+static int sdhci_msm_vreg_init(struct device *dev,
+			       struct sdhci_msm_pltfm_data *pdata, bool is_init)
+{
+	int ret = 0;
+	struct sdhci_msm_reg_data *curr_vdd_reg, *curr_vdd_io_reg;
+
+	curr_vdd_reg = pdata->vdd_data;
+	curr_vdd_io_reg = pdata->vdd_io_data;
+
+	if (!is_init)
+		/* Deregister all regulators from regulator framework */
+		return ret;
+
+	/*
+	 * Get the regulator handle from voltage regulator framework
+	 * and then try to set the voltage level for the regulator
+	 */
+	if (curr_vdd_reg) {
+		ret = sdhci_msm_vreg_init_reg(dev, curr_vdd_reg);
+		if (ret)
+			return ret;
+	}
+	if (curr_vdd_io_reg) {
+		ret = sdhci_msm_vreg_init_reg(dev, curr_vdd_io_reg);
+		if (ret)
+			return ret;
+	}
+	ret = sdhci_msm_vreg_reset(pdata);
+	if (ret)
+		dev_err(dev, "vreg reset failed (%d)\n", ret);
+
+	return ret;
+}
+
+static int sdhci_msm_set_vdd_io_vol(struct sdhci_msm_pltfm_data *pdata,
+				    enum vdd_io_level level,
+				    unsigned int voltage_level)
+{
+	int ret = 0;
+	int set_level;
+
+	struct sdhci_msm_reg_data *vdd_io_reg = pdata->vdd_io_data;
+
+	if (vdd_io_reg && regulator_is_enabled(vdd_io_reg->reg)) {
+		switch (level) {
+		case VDD_IO_LOW:
+			set_level = vdd_io_reg->low_vol_level;
+			break;
+		case VDD_IO_HIGH:
+			set_level = vdd_io_reg->high_vol_level;
+			break;
+		case VDD_IO_SET_LEVEL:
+			set_level = voltage_level;
+			break;
+		default:
+			pr_err("%s: invalid argument level = %d",
+					__func__, level);
+			return -EINVAL;
+		}
+		ret = regulator_set_voltage(vdd_io_reg->reg,
+				set_level, set_level);
+	}
+
+	return ret;
+}
+
+static irqreturn_t sdhci_msm_pwr_irq(int irq, void *data)
+{
+	struct sdhci_msm_host *msm_host = (struct sdhci_msm_host *)data;
+	u8 irq_status = 0;
+	u8 irq_ack = 0;
+	int ret = 0;
+
+	irq_status = readb_relaxed(msm_host->core_mem + CORE_PWRCTL_STATUS);
+	pr_debug("%s: Received IRQ(%d), status=0x%x\n",
+		 mmc_hostname(msm_host->mmc), irq, irq_status);
+
+	/* Clear the interrupt */
+	writeb_relaxed(irq_status, (msm_host->core_mem + CORE_PWRCTL_CLEAR));
+	/*
+	 * SDHC has core_mem and hc_mem device memory and these memory
+	 * addresses do not fall within 1KB region. Hence, any update to
+	 * core_mem address space would require an mb() to ensure this gets
+	 * completed before its next update to registers within hc_mem.
+	 */
+	mb();
+
+	/* Handle BUS ON/OFF */
+	if (irq_status & (CORE_PWRCTL_BUS_ON | CORE_PWRCTL_BUS_OFF)) {
+		bool flag = (irq_status & CORE_PWRCTL_BUS_ON) ? 1 : 0;
+		ret = sdhci_msm_setup_vreg(msm_host->pdata, flag, false);
+		if (ret)
+			irq_ack |= CORE_PWRCTL_BUS_FAIL;
+		else
+			irq_ack |= CORE_PWRCTL_BUS_SUCCESS;
+	}
+	/* Handle IO LOW/HIGH */
+	if (irq_status & (CORE_PWRCTL_IO_LOW | CORE_PWRCTL_IO_HIGH)) {
+		/* Switch voltage */
+		int io_status = (irq_status & CORE_PWRCTL_IO_LOW) ?
+		    VDD_IO_LOW : VDD_IO_HIGH;
+		ret = sdhci_msm_set_vdd_io_vol(msm_host->pdata, io_status, 0);
+		if (ret)
+			irq_ack |= CORE_PWRCTL_IO_FAIL;
+		else
+			irq_ack |= CORE_PWRCTL_IO_SUCCESS;
+	}
+
+	/* ACK status to the core */
+	writeb_relaxed(irq_ack, (msm_host->core_mem + CORE_PWRCTL_CTL));
+	/*
+	 * SDHC has core_mem and hc_mem device memory and these memory
+	 * addresses do not fall within 1KB region. Hence, any update to
+	 * core_mem address space would require an mb() to ensure this gets
+	 * completed before its next update to registers within hc_mem.
+	 */
+	mb();
+
+	pr_debug("%s: Handled IRQ(%d), ret=%d, ack=0x%x\n",
+		 mmc_hostname(msm_host->mmc), irq, ret, irq_ack);
+	return IRQ_HANDLED;
+}
+
+/* This function returns the max. current supported by VDD rail in mA */
+static unsigned int sdhci_msm_get_vdd_max_current(struct sdhci_msm_host
+						       *host)
+{
+	return host->pdata->vdd_data->hpm_uA / 1000;
+}
+
+static const struct of_device_id sdhci_msm_dt_match[] = {
+	{.compatible = "qcom,sdhci-msm"},
+};
+
+MODULE_DEVICE_TABLE(of, sdhci_msm_dt_match);
+
+static int sdhci_msm_probe(struct platform_device *pdev)
+{
+	struct sdhci_host *host;
+	struct sdhci_pltfm_host *pltfm_host;
+	struct sdhci_msm_host *msm_host;
+	struct resource *core_memres = NULL;
+	int ret = 0, dead = 0;
+	struct pinctrl	*pinctrl;
+
+	msm_host = devm_kzalloc(&pdev->dev, sizeof(struct sdhci_msm_host),
+				GFP_KERNEL);
+	if (!msm_host)
+		return -ENOMEM;
+
+	host = sdhci_pltfm_init(pdev, &msm_host->sdhci_msm_pdata, 0);
+	if (IS_ERR(host)) {
+		dev_err(mmc_dev(host->mmc), "sdhci_pltfm_init error\n");
+		return PTR_ERR(host);
+	}
+
+	pltfm_host = sdhci_priv(host);
+	pltfm_host->priv = msm_host;
+	msm_host->mmc = host->mmc;
+	msm_host->pdev = pdev;
+
+	ret = mmc_of_parse(host->mmc);
+	if (ret)
+		return ret;
+
+	/* Extract platform data */
+	if (pdev->dev.of_node) {
+		msm_host->pdata = sdhci_msm_populate_pdata(&pdev->dev);
+		if (!msm_host->pdata) {
+			dev_err(&pdev->dev, "DT parsing error\n");
+			goto pltfm_free;
+		}
+	} else {
+		dev_err(&pdev->dev, "No device tree node\n");
+		goto pltfm_free;
+	}
+
+	/* Setup pins */
+	pinctrl = devm_pinctrl_get_select_default(&pdev->dev);
+	if (IS_ERR(pinctrl))
+		dev_warn(&pdev->dev, "pins are not configured by the driver\n");
+
+	/* Setup Clocks */
+
+	/* Setup SDCC bus voter clock. */
+	msm_host->bus_clk = devm_clk_get(&pdev->dev, "bus");
+	if (!IS_ERR_OR_NULL(msm_host->bus_clk)) {
+		/* Vote for max. clk rate for max. performance */
+		ret = clk_set_rate(msm_host->bus_clk, INT_MAX);
+		if (ret)
+			goto pltfm_free;
+		ret = clk_prepare_enable(msm_host->bus_clk);
+		if (ret)
+			goto pltfm_free;
+	}
+
+	/* Setup main peripheral bus clock */
+	msm_host->pclk = devm_clk_get(&pdev->dev, "iface");
+	if (!IS_ERR(msm_host->pclk)) {
+		ret = clk_prepare_enable(msm_host->pclk);
+		if (ret) {
+			dev_err(&pdev->dev,
+				"Main peripheral clock setup failed (%d)\n",
+				ret);
+			goto bus_clk_disable;
+		}
+	}
+
+	/* Setup SDC MMC clock */
+	msm_host->clk = devm_clk_get(&pdev->dev, "core");
+	if (IS_ERR(msm_host->clk)) {
+		ret = PTR_ERR(msm_host->clk);
+		dev_err(&pdev->dev, "SDC MMC clock setup failed (%d)\n", ret);
+		goto pclk_disable;
+	}
+
+	ret = clk_prepare_enable(msm_host->clk);
+	if (ret)
+		goto pclk_disable;
+
+	/* Setup regulators */
+	ret = sdhci_msm_vreg_init(&pdev->dev, msm_host->pdata, true);
+	if (ret) {
+		dev_err(&pdev->dev, "Regulator setup failed (%d)\n", ret);
+		goto clk_disable;
+	}
+
+	/* Reset the core and Enable SDHC mode */
+	core_memres = platform_get_resource_byname(pdev,
+						   IORESOURCE_MEM, "core_mem");
+	msm_host->core_mem = devm_ioremap(&pdev->dev, core_memres->start,
+					  resource_size(core_memres));
+
+	if (!msm_host->core_mem) {
+		dev_err(&pdev->dev, "Failed to remap registers\n");
+		ret = -ENOMEM;
+		goto vreg_deinit;
+	}
+
+	/* Set SW_RST bit in POWER register (Offset 0x0) */
+	writel_relaxed(CORE_SW_RST, msm_host->core_mem + CORE_POWER);
+	/* Set HC_MODE_EN bit in HC_MODE register */
+	writel_relaxed(HC_MODE_EN, (msm_host->core_mem + CORE_HC_MODE));
+
+	/*
+	 * Following are the deviations from SDHC spec v3.0 -
+	 * 1. Card detection is handled using separate GPIO.
+	 * 2. Bus power control is handled by interacting with PMIC.
+	 */
+	host->quirks |= SDHCI_QUIRK_BROKEN_CARD_DETECTION;
+
+	/* Setup PWRCTL irq */
+	msm_host->pwr_irq = platform_get_irq_byname(pdev, "pwr_irq");
+	if (msm_host->pwr_irq < 0) {
+		dev_err(&pdev->dev, "Failed to get pwr_irq by name (%d)\n",
+			msm_host->pwr_irq);
+		goto vreg_deinit;
+	}
+	ret = devm_request_threaded_irq(&pdev->dev, msm_host->pwr_irq, NULL,
+					sdhci_msm_pwr_irq, IRQF_ONESHOT,
+					dev_name(&pdev->dev), host);
+	if (ret) {
+		dev_err(&pdev->dev, "Request threaded irq(%d) failed (%d)\n",
+			msm_host->pwr_irq, ret);
+		goto vreg_deinit;
+	}
+
+	/* Enable pwr irq interrupts */
+	writel_relaxed(INT_MASK, (msm_host->core_mem + CORE_PWRCTL_MASK));
+
+	/* Set host capabilities */
+	msm_host->mmc->caps |= msm_host->pdata->caps;
+	msm_host->mmc->caps2 |= msm_host->pdata->caps2;
+
+	ret = sdhci_add_host(host);
+	if (ret) {
+		dev_err(&pdev->dev, "Add host failed (%d)\n", ret);
+		goto vreg_deinit;
+	}
+
+	/* Set core clk rate */
+	ret = clk_set_rate(msm_host->clk, host->max_clk);
+	if (ret) {
+		dev_err(&pdev->dev, "MClk rate set failed (%d)\n", ret);
+		goto remove_host;
+	}
+
+	host->mmc->max_current_180 = host->mmc->max_current_300 =
+	host->mmc->max_current_330 = sdhci_msm_get_vdd_max_current(msm_host);
+
+	/* Successful initialization */
+	goto out;
+
+remove_host:
+	dead = (readl_relaxed(host->ioaddr + SDHCI_INT_STATUS) == 0xffffffff);
+	sdhci_remove_host(host, dead);
+vreg_deinit:
+	sdhci_msm_vreg_init(&pdev->dev, msm_host->pdata, false);
+clk_disable:
+	if (!IS_ERR(msm_host->clk))
+		clk_disable_unprepare(msm_host->clk);
+pclk_disable:
+	if (!IS_ERR(msm_host->pclk))
+		clk_disable_unprepare(msm_host->pclk);
+bus_clk_disable:
+	if (!IS_ERR_OR_NULL(msm_host->bus_clk))
+		clk_disable_unprepare(msm_host->bus_clk);
+pltfm_free:
+	sdhci_pltfm_free(pdev);
+out:
+	return ret;
+}
+
+static int sdhci_msm_remove(struct platform_device *pdev)
+{
+	struct sdhci_host *host = platform_get_drvdata(pdev);
+	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+	struct sdhci_msm_host *msm_host = pltfm_host->priv;
+	int dead = (readl_relaxed(host->ioaddr + SDHCI_INT_STATUS) ==
+		    0xffffffff);
+
+	pr_debug("%s: %s\n", dev_name(&pdev->dev), __func__);
+	sdhci_remove_host(host, dead);
+	sdhci_pltfm_free(pdev);
+	sdhci_msm_vreg_init(&pdev->dev, msm_host->pdata, false);
+	clk_disable_unprepare(msm_host->clk);
+	clk_disable_unprepare(msm_host->pclk);
+	if (!IS_ERR_OR_NULL(msm_host->bus_clk))
+		clk_disable_unprepare(msm_host->bus_clk);
+	return 0;
+}
+
+static struct platform_driver sdhci_msm_driver = {
+	.probe = sdhci_msm_probe,
+	.remove = sdhci_msm_remove,
+	.driver = {
+		   .name = "sdhci_msm",
+		   .owner = THIS_MODULE,
+		   .of_match_table = of_match_ptr(sdhci_msm_dt_match),
+		   },
+};
+
+module_platform_driver(sdhci_msm_driver);
+
+MODULE_DESCRIPTION("Qualcomm Secure Digital Host Controller Interface driver");
+MODULE_LICENSE("GPL v2");
-- 
1.7.9.5