[PATCH V2 0/8] Add Embedded USB Debugger (EUD) driver

[PATCH V2 0/8] Add Embedded USB Debugger (EUD) driver

[Souradeep Chowdhury]

This is a series of patches that implements a driver for the control
peripheral, EUD (Embedded USB Debugger). The EUD is a mini-USB hub
implemented on chip to support the USB-based debug and trace capabilities.
Apart from debug capabilities, EUD has a control peripheral. Control
Peripheral is on when EUD is on and gets signals like USB attach, pet
EUD etc. EUD driver listens to events like USB attach or detach and then
informs the USB about these events via ROLE-SWITCH. At regular intervals,
the EUD driver receives an interrupt to pet the driver indicating that
the software is functional.

Changes in V2

*Fixed the yaml issue and also implemeted comments on yaml in V1.

Changes in V1

* EUD has now been mapped as a separate DT node as it is an independent QCOM IP.

* EUD is attached to the connector child of dwc3 via port end point since EUD
  driver needs the connector for role-switching.

* EUD driver has been moved now to drivers/soc/qcom/qcom_eud.c.

* All the comments from version 0 of the patch has been implemented.

Souradeep Chowdhury (8):
  dt-bindings: Add the yaml bindings for EUD
  dt-bindings: connector: Add property for EUD type-C connector
  bindings: usb: dwc3: Update dwc3 properties for EUD connector
  usb: dwc3: drd: Register the eud connector child node for dwc3
  soc: qcom: eud: Add driver support for Embedded USB Debugger(EUD)
  arm64: dts: qcom: sc7280: Add EUD dt node and dwc3 connector
  arm64: dts: qcom: sc7280: Set the default dr_mode for usb2
  MAINTAINERS: Add maintainer entry for EUD

 Documentation/ABI/testing/sysfs-driver-eud         |   9 +
 .../bindings/connector/usb-connector.yaml          |   4 +
 .../devicetree/bindings/soc/qcom/qcom,eud.yaml     |  50 ++++
 .../devicetree/bindings/usb/snps,dwc3.yaml         |   6 +
 MAINTAINERS                                        |   8 +
 arch/arm64/boot/dts/qcom/sc7280-idp.dts            |   4 +
 arch/arm64/boot/dts/qcom/sc7280.dtsi               |  25 ++
 drivers/soc/qcom/Kconfig                           |  10 +
 drivers/soc/qcom/Makefile                          |   1 +
 drivers/soc/qcom/qcom_eud.c                        | 268 +++++++++++++++++++++
 drivers/usb/dwc3/drd.c                             |  26 ++
 11 files changed, 411 insertions(+)
 create mode 100644 Documentation/ABI/testing/sysfs-driver-eud
 create mode 100644 Documentation/devicetree/bindings/soc/qcom/qcom,eud.yaml
 create mode 100644 drivers/soc/qcom/qcom_eud.c

--
2.7.4

[PATCH V2 1/8] dt-bindings: Add the yaml bindings for EUD

[Souradeep Chowdhury]

Documentation for Embedded USB Debugger(EUD) device tree
bindings in yaml format.

Signed-off-by: Souradeep Chowdhury <quic_schowdhu@quicinc.com>
---
 .../devicetree/bindings/soc/qcom/qcom,eud.yaml     | 50 ++++++++++++++++++++++
 1 file changed, 50 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/soc/qcom/qcom,eud.yaml

diff --git a/Documentation/devicetree/bindings/soc/qcom/qcom,eud.yaml b/Documentation/devicetree/bindings/soc/qcom/qcom,eud.yaml
new file mode 100644
index 0000000..0c49d08
--- /dev/null
+++ b/Documentation/devicetree/bindings/soc/qcom/qcom,eud.yaml
@@ -0,0 +1,50 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: "http://devicetree.org/schemas/soc/qcom/qcom,eud.yaml#"
+$schema: "http://devicetree.org/meta-schemas/core.yaml#"
+
+title: Qualcomm Embedded USB Debugger
+
+maintainers:
+  - Souradeep Chowdhury <schowdhu@codeaurora.org>
+
+description:
+  This binding is used to describe the Qualcomm Embedded USB Debugger, which is
+  mini USB-hub implemented on chip to support USB-based debug capabilities.
+
+properties:
+  compatible:
+    items:
+      - enum:
+          - qcom,sc7280-eud
+      - const: qcom,eud
+
+  reg:
+    items:
+      - description: EUD Base Register Region
+      - description: EUD Mode Manager Register
+
+  interrupts:
+    description:
+      EUD interrupt
+
+  port:
+    description:
+      This port is to be attached to the endpoint of the connector child of
+      DWC3 controller node. The controller has the "usb-role-switch" property.
+    $ref: /schemas/graph.yaml#/properties/port
+
+required:
+  - compatible
+  - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    eud@88e0000 {
+           compatible = "qcom,sc7280-eud","qcom,eud";
+           reg = <0x88e0000 0x2000>,
+                 <0x88e2000 0x1000>;
+    };
-- 
2.7.4

[PATCH V2 2/8] dt-bindings: connector: Add property for EUD type-C connector

[Souradeep Chowdhury]

Added the property for EUD(Embedded USB Debugger) connector. EUD
is a mini usb hub with debug and trace capabilities and it has a
type C connector attached to it for role-switching. This connector
is attached to EUD via port.

Signed-off-by: Souradeep Chowdhury <quic_schowdhu@quicinc.com>
---
 Documentation/devicetree/bindings/connector/usb-connector.yaml | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/Documentation/devicetree/bindings/connector/usb-connector.yaml b/Documentation/devicetree/bindings/connector/usb-connector.yaml
index 7eb8659..bd1823a 100644
--- a/Documentation/devicetree/bindings/connector/usb-connector.yaml
+++ b/Documentation/devicetree/bindings/connector/usb-connector.yaml
@@ -30,6 +30,10 @@ properties:
           - const: samsung,usb-connector-11pin
           - const: usb-b-connector
 
+      - items:
+          - const: qcom,usb-connector-eud
+          - const: usb-c-connector
+
   label:
     description: Symbolic name for the connector.
 
-- 
2.7.4

[PATCH V2 3/8] bindings: usb: dwc3: Update dwc3 properties for EUD connector

[Souradeep Chowdhury]

Add the connector property for dwc3 node. This connector can
be used to role-switch the controller from device to host and
vice versa.

Signed-off-by: Souradeep Chowdhury <quic_schowdhu@quicinc.com>
---
 Documentation/devicetree/bindings/usb/snps,dwc3.yaml | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/Documentation/devicetree/bindings/usb/snps,dwc3.yaml b/Documentation/devicetree/bindings/usb/snps,dwc3.yaml
index 078fb78..9382168 100644
--- a/Documentation/devicetree/bindings/usb/snps,dwc3.yaml
+++ b/Documentation/devicetree/bindings/usb/snps,dwc3.yaml
@@ -318,6 +318,12 @@ properties:
     items:
       enum: [1, 4, 8, 16, 32, 64, 128, 256]
 
+  connector:
+    type: object
+    $ref: /connector/usb-connector.yaml#
+    description:
+      Connector for dual role switch, especially for "eud-usb-c-connector"
+
 unevaluatedProperties: false
 
 required:
-- 
2.7.4

[PATCH V2 4/8] usb: dwc3: drd: Register the eud connector child node for dwc3

[Souradeep Chowdhury]

Register the child node for dwc3 which is the "eud_usb_connector".
The eud driver will be able to switch the usb role from device to
host and vice versa using the role switch property of dwc3 node.

Signed-off-by: Souradeep Chowdhury <quic_schowdhu@quicinc.com>
---
 drivers/usb/dwc3/drd.c | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/drivers/usb/dwc3/drd.c b/drivers/usb/dwc3/drd.c
index d7f7683..b4ea55c 100644
--- a/drivers/usb/dwc3/drd.c
+++ b/drivers/usb/dwc3/drd.c
@@ -8,6 +8,7 @@
  */
 
 #include <linux/extcon.h>
+#include <linux/of_platform.h>
 #include <linux/of_graph.h>
 #include <linux/platform_device.h>
 #include <linux/property.h>
@@ -164,6 +165,27 @@ static int dwc3_otg_get_irq(struct dwc3 *dwc)
 	return irq;
 }
 
+static int dwc3_register_eud(struct dwc3 *dwc)
+{
+	struct device		*dev = dwc->dev;
+	struct device_node	*np = dev->of_node;
+	int                     ret;
+
+	of_get_child_by_name(np, "eud_usb_connector");
+	if (!np) {
+		dev_dbg(dev, "no usb_connector child node specified\n");
+		return 0;
+	}
+
+	ret = of_platform_populate(np, NULL, NULL, dev);
+	if (ret) {
+		dev_err(dev, "failed to register usb_connector - %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
 void dwc3_otg_init(struct dwc3 *dwc)
 {
 	u32 reg;
@@ -580,6 +602,10 @@ int dwc3_drd_init(struct dwc3 *dwc)
 		ret = dwc3_setup_role_switch(dwc);
 		if (ret < 0)
 			return ret;
+
+		ret = dwc3_register_eud(dwc);
+		if (ret < 0)
+			return ret;
 	} else if (dwc->edev) {
 		dwc->edev_nb.notifier_call = dwc3_drd_notifier;
 		ret = extcon_register_notifier(dwc->edev, EXTCON_USB_HOST,
-- 
2.7.4

[PATCH V2 5/8] soc: qcom: eud: Add driver support for Embedded USB Debugger(EUD)

[Souradeep Chowdhury]

Add support for control peripheral of EUD (Embedded USB Debugger) to
listen to events such as USB attach/detach, pet EUD to indicate software
is functional.Reusing the platform device kobj, sysfs entry 'enable' is
created to enable or disable EUD.

To enable the eud the following needs to be done
echo 1 > /sys/bus/platform/.../enable

To disable eud, following is the command
echo 0 > /sys/bus/platform/.../enable

Signed-off-by: Souradeep Chowdhury <quic_schowdhu@quicinc.com>
---
 Documentation/ABI/testing/sysfs-driver-eud |   9 +
 drivers/soc/qcom/Kconfig                   |  10 ++
 drivers/soc/qcom/Makefile                  |   1 +
 drivers/soc/qcom/qcom_eud.c                | 268 +++++++++++++++++++++++++++++
 4 files changed, 288 insertions(+)
 create mode 100644 Documentation/ABI/testing/sysfs-driver-eud
 create mode 100644 drivers/soc/qcom/qcom_eud.c

diff --git a/Documentation/ABI/testing/sysfs-driver-eud b/Documentation/ABI/testing/sysfs-driver-eud
new file mode 100644
index 0000000..eaf2e82
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-driver-eud
@@ -0,0 +1,9 @@
+What:		/sys/bus/platform/drivers/eud/.../enable
+Date:           October 2021
+Contact:        Souradeep Chowdhury <quic_schowdhu@quicinc.com>
+Description:
+		The Enable/Disable sysfs interface for Embedded
+		USB Debugger(EUD). This enables and disables the
+		EUD based on a 1 or a 0 value. By enabling EUD,
+		the user is able to activate the mini-usb hub of
+		EUD for debug and trace capabilities.
diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig
index 79b568f..a4db41b 100644
--- a/drivers/soc/qcom/Kconfig
+++ b/drivers/soc/qcom/Kconfig
@@ -42,6 +42,16 @@ config QCOM_CPR
 	  To compile this driver as a module, choose M here: the module will
 	  be called qcom-cpr

+config QCOM_EUD
+	tristate "QCOM Embedded USB Debugger(EUD) Driver"
+	select USB_ROLE_SWITCH
+	help
+	  This module enables support for Qualcomm Technologies, Inc.
+	  Embedded USB Debugger (EUD). The EUD is a control peripheral
+	  which reports VBUS attach/detach events and has USB-based
+	  debug and trace capabilities. On selecting m, the module name
+	  that is built is qcom_eud.ko
+
 config QCOM_GENI_SE
 	tristate "QCOM GENI Serial Engine Driver"
 	depends on ARCH_QCOM || COMPILE_TEST
diff --git a/drivers/soc/qcom/Makefile b/drivers/soc/qcom/Makefile
index ad675a6..3331a40 100644
--- a/drivers/soc/qcom/Makefile
+++ b/drivers/soc/qcom/Makefile
@@ -4,6 +4,7 @@ obj-$(CONFIG_QCOM_AOSS_QMP) +=	qcom_aoss.o
 obj-$(CONFIG_QCOM_GENI_SE) +=	qcom-geni-se.o
 obj-$(CONFIG_QCOM_COMMAND_DB) += cmd-db.o
 obj-$(CONFIG_QCOM_CPR)		+= cpr.o
+obj-$(CONFIG_QCOM_EUD)          += qcom_eud.o
 obj-$(CONFIG_QCOM_GSBI)	+=	qcom_gsbi.o
 obj-$(CONFIG_QCOM_MDT_LOADER)	+= mdt_loader.o
 obj-$(CONFIG_QCOM_OCMEM)	+= ocmem.o
diff --git a/drivers/soc/qcom/qcom_eud.c b/drivers/soc/qcom/qcom_eud.c
new file mode 100644
index 0000000..613ac41
--- /dev/null
+++ b/drivers/soc/qcom/qcom_eud.c
@@ -0,0 +1,268 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2015-2021, The Linux Foundation. All rights reserved.
+ */
+
+#include <linux/bitops.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <linux/usb/role.h>
+
+#define EUD_REG_INT1_EN_MASK	0x0024
+#define EUD_REG_INT_STATUS_1	0x0044
+#define EUD_REG_CTL_OUT_1	0x0074
+#define EUD_REG_VBUS_INT_CLR	0x0080
+#define EUD_REG_CSR_EUD_EN	0x1014
+#define EUD_REG_SW_ATTACH_DET	0x1018
+#define EUD_REG_EUD_EN2         0x0000
+
+#define EUD_ENABLE		BIT(0)
+#define EUD_INT_PET_EUD		BIT(0)
+#define EUD_INT_VBUS		BIT(2)
+#define EUD_INT_SAFE_MODE	BIT(4)
+#define EUD_INT_ALL		(EUD_INT_VBUS|EUD_INT_SAFE_MODE)
+
+struct eud_chip {
+	struct device			*dev;
+	struct usb_role_switch		*role_sw;
+	void __iomem			*eud_reg_base;
+	void __iomem			*eud_mode_mgr2_phys_base;
+	unsigned int			int_status;
+	int				eud_irq;
+	bool				enable;
+	bool				usb_attach;
+
+};
+
+static int enable_eud(struct eud_chip *priv)
+{
+	writel(EUD_ENABLE, priv->eud_reg_base + EUD_REG_CSR_EUD_EN);
+	writel(EUD_INT_VBUS | EUD_INT_SAFE_MODE,
+			priv->eud_reg_base + EUD_REG_INT1_EN_MASK);
+	writel(1, priv->eud_mode_mgr2_phys_base + EUD_REG_EUD_EN2);
+
+	return usb_role_switch_set_role(priv->role_sw, USB_ROLE_DEVICE);
+}
+
+static void disable_eud(struct eud_chip *priv)
+{
+	writel(0, priv->eud_reg_base + EUD_REG_CSR_EUD_EN);
+	writel(0, priv->eud_mode_mgr2_phys_base + EUD_REG_EUD_EN2);
+}
+
+static ssize_t enable_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct eud_chip *chip = dev_get_drvdata(dev);
+
+	return sysfs_emit(buf, "%d\n", chip->enable);
+}
+
+static ssize_t enable_store(struct device *dev,
+		struct device_attribute *attr,
+		const char *buf, size_t count)
+{
+	struct eud_chip *chip = dev_get_drvdata(dev);
+	bool enable;
+	int ret;
+
+	if (kstrtobool(buf, &enable))
+		return -EINVAL;
+
+	if (enable) {
+		ret = enable_eud(chip);
+		if (!ret)
+			chip->enable = enable;
+	} else {
+		disable_eud(chip);
+	}
+
+	return count;
+}
+
+static DEVICE_ATTR_RW(enable);
+
+static struct attribute *eud_attrs[] = {
+	&dev_attr_enable.attr,
+	NULL,
+};
+
+static struct attribute_group attr_group = {
+	.attrs = eud_attrs,
+};
+
+static const struct attribute_group *attr_groups[] = {
+	&attr_group,
+	NULL
+};
+
+static void usb_attach_detach(struct eud_chip *chip)
+{
+	u32 reg;
+
+	/* read ctl_out_1[4] to find USB attach or detach event */
+	reg = readl(chip->eud_reg_base + EUD_REG_CTL_OUT_1);
+	if (reg & EUD_INT_SAFE_MODE)
+		chip->usb_attach = true;
+	else
+		chip->usb_attach = false;
+
+	/* set and clear vbus_int_clr[0] to clear interrupt */
+	writel(BIT(0), chip->eud_reg_base + EUD_REG_VBUS_INT_CLR);
+	writel(0, chip->eud_reg_base + EUD_REG_VBUS_INT_CLR);
+}
+
+static void pet_eud(struct eud_chip *chip)
+{
+	u32 reg;
+	int ret;
+
+	/* read sw_attach_det[0] to find attach/detach event */
+	reg = readl(chip->eud_reg_base +  EUD_REG_SW_ATTACH_DET);
+	if (reg & EUD_INT_PET_EUD) {
+		/* Detach & Attach pet for EUD */
+		writel(0, chip->eud_reg_base + EUD_REG_SW_ATTACH_DET);
+		/* Delay to make sure detach pet is done before attach pet */
+		ret = readl_poll_timeout(chip->eud_reg_base + EUD_REG_SW_ATTACH_DET,
+					reg, (reg == 0), 1, 100);
+		if (ret) {
+			dev_err(chip->dev, "Detach pet failed\n");
+			return;
+		}
+
+		writel(EUD_INT_PET_EUD, chip->eud_reg_base +
+				EUD_REG_SW_ATTACH_DET);
+	} else {
+		/* Attach pet for EUD */
+		writel(EUD_INT_PET_EUD, chip->eud_reg_base +
+				EUD_REG_SW_ATTACH_DET);
+	}
+}
+
+static irqreturn_t handle_eud_irq(int irq, void *data)
+{
+	struct eud_chip *chip = data;
+	u32 reg;
+
+	/* read status register and find out which interrupt triggered */
+	reg = readl(chip->eud_reg_base +  EUD_REG_INT_STATUS_1);
+	switch (reg & EUD_INT_ALL) {
+	case EUD_INT_VBUS:
+		chip->int_status = EUD_INT_VBUS;
+		usb_attach_detach(chip);
+		return IRQ_WAKE_THREAD;
+	case EUD_INT_SAFE_MODE:
+		pet_eud(chip);
+		break;
+	default:
+		return IRQ_NONE;
+	}
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t handle_eud_irq_thread(int irq, void *data)
+{
+	struct eud_chip *chip = data;
+	int ret;
+
+	if (chip->int_status == EUD_INT_VBUS) {
+		if (chip->usb_attach)
+			ret = usb_role_switch_set_role(chip->role_sw, USB_ROLE_DEVICE);
+		else
+			ret = usb_role_switch_set_role(chip->role_sw, USB_ROLE_HOST);
+		if (ret)
+			dev_err(chip->dev, "failed to set role switch\n");
+	}
+
+	return IRQ_HANDLED;
+}
+
+static int eud_probe(struct platform_device *pdev)
+{
+	struct eud_chip *chip;
+	struct fwnode_handle *fwnode = pdev->dev.fwnode, *ep, *connector;
+	int ret;
+
+	chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
+	if (!chip)
+		return -ENOMEM;
+
+	chip->dev = &pdev->dev;
+
+	ep = fwnode_graph_get_next_endpoint(fwnode, NULL);
+	if (!ep)
+		return -ENODEV;
+
+	connector = fwnode_graph_get_remote_port_parent(ep);
+	fwnode_handle_put(ep);
+	if (!connector)
+		return -ENODEV;
+
+	chip->role_sw = fwnode_usb_role_switch_get(connector);
+	if (IS_ERR(chip->role_sw)) {
+		return dev_err_probe(chip->dev, PTR_ERR(chip->role_sw),
+					"failed to get role switch\n");
+	}
+
+	chip->eud_reg_base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(chip->eud_reg_base))
+		return PTR_ERR(chip->eud_reg_base);
+
+	chip->eud_mode_mgr2_phys_base = devm_platform_ioremap_resource(pdev, 1);
+	if (IS_ERR(chip->eud_mode_mgr2_phys_base))
+		return PTR_ERR(chip->eud_mode_mgr2_phys_base);
+
+	chip->eud_irq = platform_get_irq(pdev, 0);
+	ret = devm_request_threaded_irq(&pdev->dev, chip->eud_irq, handle_eud_irq,
+			handle_eud_irq_thread, IRQF_ONESHOT, NULL, chip);
+	if (ret)
+		return dev_err_probe(chip->dev, ret, "failed to allocate irq\n");
+
+	enable_irq_wake(chip->eud_irq);
+
+	platform_set_drvdata(pdev, chip);
+
+	return 0;
+}
+
+static int eud_remove(struct platform_device *pdev)
+{
+	struct eud_chip *chip = platform_get_drvdata(pdev);
+
+	if (chip->enable)
+		disable_eud(chip);
+
+	device_init_wakeup(&pdev->dev, false);
+	disable_irq_wake(chip->eud_irq);
+
+	return 0;
+}
+
+static const struct of_device_id eud_dt_match[] = {
+	{ .compatible = "qcom,sc7280-eud" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, eud_dt_match);
+
+static struct platform_driver eud_driver = {
+	.probe		= eud_probe,
+	.remove		= eud_remove,
+	.driver		= {
+		.name		= "eud",
+		.dev_groups	= attr_groups,
+		.of_match_table = eud_dt_match,
+	},
+};
+module_platform_driver(eud_driver);
+
+MODULE_DESCRIPTION("QTI EUD driver");
+MODULE_LICENSE("GPL v2");
--
2.7.4

[PATCH V2 6/8] arm64: dts: qcom: sc7280: Add EUD dt node and dwc3 connector

[Souradeep Chowdhury]

Add the Embedded USB Debugger(EUD) device tree node. The
node contains EUD base register region and EUD mode
manager register regions along with the interrupt entry.
Also add the connector to EUD which is mapped as the child
of dwc3. The connector is attached to EUD via port. Also add
the role-switch property to dwc3 node.

Signed-off-by: Souradeep Chowdhury <quic_schowdhu@quicinc.com>
---
 arch/arm64/boot/dts/qcom/sc7280.dtsi | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/arch/arm64/boot/dts/qcom/sc7280.dtsi b/arch/arm64/boot/dts/qcom/sc7280.dtsi
index 53a21d0..2d14e5c 100644
--- a/arch/arm64/boot/dts/qcom/sc7280.dtsi
+++ b/arch/arm64/boot/dts/qcom/sc7280.dtsi
@@ -1315,6 +1315,18 @@
 				phys = <&usb_2_hsphy>;
 				phy-names = "usb2-phy";
 				maximum-speed = "high-speed";
+				usb-role-switch;
+				usb_con: eud_usb_connector {
+					compatible = "qcom,usb-connector-eud",
+						     "usb-c-connector";
+					ports {
+						port@0 {
+							usb2_role_switch: endpoint {
+								remote-endpoint = <&eud_ep>;
+							};
+						};
+					};
+				};
 			};
 		};
 
@@ -1339,6 +1351,19 @@
 			interrupts = <GIC_SPI 582 IRQ_TYPE_LEVEL_HIGH>;
 		};
 
+		eud:  eud@88e0000 {
+			compatible = "qcom,sc7280-eud","qcom,eud";
+			reg = <0 0x88e0000 0 0x2000>,
+			      <0 0x88e2000 0 0x1000>;
+			interrupt-parent = <&pdc>;
+			interrupts = <11 IRQ_TYPE_LEVEL_HIGH>;
+			port {
+				eud_ep: endpoint {
+					remote-endpoint = <&usb2_role_switch>;
+				};
+			};
+		};
+
 		nsp_noc: interconnect@a0c0000 {
 			reg = <0 0x0a0c0000 0 0x10000>;
 			compatible = "qcom,sc7280-nsp-noc";
-- 
2.7.4

[PATCH V2 7/8] arm64: dts: qcom: sc7280: Set the default dr_mode for usb2

[Souradeep Chowdhury]

Set the default dr_mode for usb2 node to "otg" to enable.
role-switch for EUD(Embedded USB Debugger) connector node.

Signed-off-by: Souradeep Chowdhury <quic_schowdhu@quicinc.com>
---
 arch/arm64/boot/dts/qcom/sc7280-idp.dts | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/arch/arm64/boot/dts/qcom/sc7280-idp.dts b/arch/arm64/boot/dts/qcom/sc7280-idp.dts
index 64fc22a..7c69c78 100644
--- a/arch/arm64/boot/dts/qcom/sc7280-idp.dts
+++ b/arch/arm64/boot/dts/qcom/sc7280-idp.dts
@@ -61,6 +61,10 @@
 	modem-init;
 };
 
+&usb_2_dwc3 {
+	dr_mode = "otg";
+};
+
 &pmk8350_vadc {
 	pmr735a_die_temp {
 		reg = <PMR735A_ADC7_DIE_TEMP>;
-- 
2.7.4

[PATCH V2 8/8] MAINTAINERS: Add maintainer entry for EUD

[Souradeep Chowdhury]

Add the entry for maintainer for EUD driver
and other associated files.

Signed-off-by: Souradeep Chowdhury <quic_schowdhu@quicinc.com>
---
 MAINTAINERS | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index 0227e15..54f616a 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -7018,6 +7018,14 @@ F:	include/trace/events/mdio.h
 F:	include/uapi/linux/mdio.h
 F:	include/uapi/linux/mii.h

+EUD-QCOM
+M:	Souradeep Chowdhury <quic_schowdhu@quicinc.com>
+L:	linux-arm-msm@vger.kernel.org
+S:	Maintained
+F:	Documentation/ABI/testing/sysfs-driver-eud
+F:	Documentation/devicetree/bindings/arm/msm/qcom,eud.yaml
+F:	drivers/usb/common/qcom_eud.c
+
 EXFAT FILE SYSTEM
 M:	Namjae Jeon <linkinjeon@kernel.org>
 M:	Sungjong Seo <sj1557.seo@samsung.com>
--
2.7.4

Re: [PATCH V2 5/8] soc: qcom: eud: Add driver support for Embedded USB Debugger(EUD)

[Greg KH]

On Thu, Dec 02, 2021 at 03:21:24PM +0530, Souradeep Chowdhury wrote:
> Add support for control peripheral of EUD (Embedded USB Debugger) to
> listen to events such as USB attach/detach, pet EUD to indicate software
> is functional.Reusing the platform device kobj, sysfs entry 'enable' is
> created to enable or disable EUD.
> 
> To enable the eud the following needs to be done
> echo 1 > /sys/bus/platform/.../enable
> 
> To disable eud, following is the command
> echo 0 > /sys/bus/platform/.../enable
> 
> Signed-off-by: Souradeep Chowdhury <quic_schowdhu@quicinc.com>
> ---
>  Documentation/ABI/testing/sysfs-driver-eud |   9 +
>  drivers/soc/qcom/Kconfig                   |  10 ++
>  drivers/soc/qcom/Makefile                  |   1 +
>  drivers/soc/qcom/qcom_eud.c                | 268 +++++++++++++++++++++++++++++
>  4 files changed, 288 insertions(+)
>  create mode 100644 Documentation/ABI/testing/sysfs-driver-eud
>  create mode 100644 drivers/soc/qcom/qcom_eud.c
> 
> diff --git a/Documentation/ABI/testing/sysfs-driver-eud b/Documentation/ABI/testing/sysfs-driver-eud
> new file mode 100644
> index 0000000..eaf2e82
> --- /dev/null
> +++ b/Documentation/ABI/testing/sysfs-driver-eud
> @@ -0,0 +1,9 @@
> +What:		/sys/bus/platform/drivers/eud/.../enable
> +Date:           October 2021

You sent this patch in December 2021 :(



> +Contact:        Souradeep Chowdhury <quic_schowdhu@quicinc.com>
> +Description:
> +		The Enable/Disable sysfs interface for Embedded
> +		USB Debugger(EUD). This enables and disables the
> +		EUD based on a 1 or a 0 value. By enabling EUD,
> +		the user is able to activate the mini-usb hub of
> +		EUD for debug and trace capabilities.
> diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig
> index 79b568f..a4db41b 100644
> --- a/drivers/soc/qcom/Kconfig
> +++ b/drivers/soc/qcom/Kconfig
> @@ -42,6 +42,16 @@ config QCOM_CPR
>  	  To compile this driver as a module, choose M here: the module will
>  	  be called qcom-cpr
> 
> +config QCOM_EUD
> +	tristate "QCOM Embedded USB Debugger(EUD) Driver"
> +	select USB_ROLE_SWITCH
> +	help
> +	  This module enables support for Qualcomm Technologies, Inc.
> +	  Embedded USB Debugger (EUD). The EUD is a control peripheral
> +	  which reports VBUS attach/detach events and has USB-based
> +	  debug and trace capabilities. On selecting m, the module name
> +	  that is built is qcom_eud.ko
> +
>  config QCOM_GENI_SE
>  	tristate "QCOM GENI Serial Engine Driver"
>  	depends on ARCH_QCOM || COMPILE_TEST
> diff --git a/drivers/soc/qcom/Makefile b/drivers/soc/qcom/Makefile
> index ad675a6..3331a40 100644
> --- a/drivers/soc/qcom/Makefile
> +++ b/drivers/soc/qcom/Makefile
> @@ -4,6 +4,7 @@ obj-$(CONFIG_QCOM_AOSS_QMP) +=	qcom_aoss.o
>  obj-$(CONFIG_QCOM_GENI_SE) +=	qcom-geni-se.o
>  obj-$(CONFIG_QCOM_COMMAND_DB) += cmd-db.o
>  obj-$(CONFIG_QCOM_CPR)		+= cpr.o
> +obj-$(CONFIG_QCOM_EUD)          += qcom_eud.o
>  obj-$(CONFIG_QCOM_GSBI)	+=	qcom_gsbi.o
>  obj-$(CONFIG_QCOM_MDT_LOADER)	+= mdt_loader.o
>  obj-$(CONFIG_QCOM_OCMEM)	+= ocmem.o
> diff --git a/drivers/soc/qcom/qcom_eud.c b/drivers/soc/qcom/qcom_eud.c
> new file mode 100644
> index 0000000..613ac41
> --- /dev/null
> +++ b/drivers/soc/qcom/qcom_eud.c
> @@ -0,0 +1,268 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (c) 2015-2021, The Linux Foundation. All rights reserved.
> + */
> +
> +#include <linux/bitops.h>
> +#include <linux/delay.h>
> +#include <linux/err.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/iopoll.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/platform_device.h>
> +#include <linux/slab.h>
> +#include <linux/sysfs.h>
> +#include <linux/usb/role.h>
> +
> +#define EUD_REG_INT1_EN_MASK	0x0024
> +#define EUD_REG_INT_STATUS_1	0x0044
> +#define EUD_REG_CTL_OUT_1	0x0074
> +#define EUD_REG_VBUS_INT_CLR	0x0080
> +#define EUD_REG_CSR_EUD_EN	0x1014
> +#define EUD_REG_SW_ATTACH_DET	0x1018
> +#define EUD_REG_EUD_EN2         0x0000
> +
> +#define EUD_ENABLE		BIT(0)
> +#define EUD_INT_PET_EUD		BIT(0)
> +#define EUD_INT_VBUS		BIT(2)
> +#define EUD_INT_SAFE_MODE	BIT(4)
> +#define EUD_INT_ALL		(EUD_INT_VBUS|EUD_INT_SAFE_MODE)
> +
> +struct eud_chip {
> +	struct device			*dev;
> +	struct usb_role_switch		*role_sw;
> +	void __iomem			*eud_reg_base;
> +	void __iomem			*eud_mode_mgr2_phys_base;
> +	unsigned int			int_status;
> +	int				eud_irq;
> +	bool				enable;
> +	bool				usb_attach;
> +
> +};
> +
> +static int enable_eud(struct eud_chip *priv)
> +{
> +	writel(EUD_ENABLE, priv->eud_reg_base + EUD_REG_CSR_EUD_EN);
> +	writel(EUD_INT_VBUS | EUD_INT_SAFE_MODE,
> +			priv->eud_reg_base + EUD_REG_INT1_EN_MASK);
> +	writel(1, priv->eud_mode_mgr2_phys_base + EUD_REG_EUD_EN2);
> +
> +	return usb_role_switch_set_role(priv->role_sw, USB_ROLE_DEVICE);
> +}
> +
> +static void disable_eud(struct eud_chip *priv)
> +{
> +	writel(0, priv->eud_reg_base + EUD_REG_CSR_EUD_EN);
> +	writel(0, priv->eud_mode_mgr2_phys_base + EUD_REG_EUD_EN2);
> +}
> +
> +static ssize_t enable_show(struct device *dev,
> +		struct device_attribute *attr, char *buf)
> +{
> +	struct eud_chip *chip = dev_get_drvdata(dev);
> +
> +	return sysfs_emit(buf, "%d\n", chip->enable);
> +}
> +
> +static ssize_t enable_store(struct device *dev,
> +		struct device_attribute *attr,
> +		const char *buf, size_t count)
> +{
> +	struct eud_chip *chip = dev_get_drvdata(dev);
> +	bool enable;
> +	int ret;
> +
> +	if (kstrtobool(buf, &enable))
> +		return -EINVAL;
> +
> +	if (enable) {
> +		ret = enable_eud(chip);
> +		if (!ret)
> +			chip->enable = enable;
> +	} else {
> +		disable_eud(chip);
> +	}
> +
> +	return count;
> +}
> +
> +static DEVICE_ATTR_RW(enable);
> +
> +static struct attribute *eud_attrs[] = {
> +	&dev_attr_enable.attr,
> +	NULL,
> +};
> +
> +static struct attribute_group attr_group = {
> +	.attrs = eud_attrs,
> +};
> +
> +static const struct attribute_group *attr_groups[] = {
> +	&attr_group,
> +	NULL
> +};

ATTRIBUTE_GROUPS()?

thanks,

greg k-h

Re: [PATCH V2 5/8] soc: qcom: eud: Add driver support for Embedded USB Debugger(EUD)

[Souradeep Chowdhury]

On 12/3/2021 4:34 PM, Greg KH wrote:
> On Thu, Dec 02, 2021 at 03:21:24PM +0530, Souradeep Chowdhury wrote:
>> Add support for control peripheral of EUD (Embedded USB Debugger) to
>> listen to events such as USB attach/detach, pet EUD to indicate software
>> is functional.Reusing the platform device kobj, sysfs entry 'enable' is
>> created to enable or disable EUD.
>>
>> To enable the eud the following needs to be done
>> echo 1 > /sys/bus/platform/.../enable
>>
>> To disable eud, following is the command
>> echo 0 > /sys/bus/platform/.../enable
>>
>> Signed-off-by: Souradeep Chowdhury <quic_schowdhu@quicinc.com>
>> ---
>>   Documentation/ABI/testing/sysfs-driver-eud |   9 +
>>   drivers/soc/qcom/Kconfig                   |  10 ++
>>   drivers/soc/qcom/Makefile                  |   1 +
>>   drivers/soc/qcom/qcom_eud.c                | 268 +++++++++++++++++++++++++++++
>>   4 files changed, 288 insertions(+)
>>   create mode 100644 Documentation/ABI/testing/sysfs-driver-eud
>>   create mode 100644 drivers/soc/qcom/qcom_eud.c
>>
>> diff --git a/Documentation/ABI/testing/sysfs-driver-eud b/Documentation/ABI/testing/sysfs-driver-eud
>> new file mode 100644
>> index 0000000..eaf2e82
>> --- /dev/null
>> +++ b/Documentation/ABI/testing/sysfs-driver-eud
>> @@ -0,0 +1,9 @@
>> +What:		/sys/bus/platform/drivers/eud/.../enable
>> +Date:           October 2021
> You sent this patch in December 2021 :(
>
Ack
>
>> +Contact:        Souradeep Chowdhury <quic_schowdhu@quicinc.com>
>> +Description:
>> +		The Enable/Disable sysfs interface for Embedded
>> +		USB Debugger(EUD). This enables and disables the
>> +		EUD based on a 1 or a 0 value. By enabling EUD,
>> +		the user is able to activate the mini-usb hub of
>> +		EUD for debug and trace capabilities.
>> diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig
>> index 79b568f..a4db41b 100644
>> --- a/drivers/soc/qcom/Kconfig
>> +++ b/drivers/soc/qcom/Kconfig
>> @@ -42,6 +42,16 @@ config QCOM_CPR
>>   	  To compile this driver as a module, choose M here: the module will
>>   	  be called qcom-cpr
>>
>> +config QCOM_EUD
>> +	tristate "QCOM Embedded USB Debugger(EUD) Driver"
>> +	select USB_ROLE_SWITCH
>> +	help
>> +	  This module enables support for Qualcomm Technologies, Inc.
>> +	  Embedded USB Debugger (EUD). The EUD is a control peripheral
>> +	  which reports VBUS attach/detach events and has USB-based
>> +	  debug and trace capabilities. On selecting m, the module name
>> +	  that is built is qcom_eud.ko
>> +
>>   config QCOM_GENI_SE
>>   	tristate "QCOM GENI Serial Engine Driver"
>>   	depends on ARCH_QCOM || COMPILE_TEST
>> diff --git a/drivers/soc/qcom/Makefile b/drivers/soc/qcom/Makefile
>> index ad675a6..3331a40 100644
>> --- a/drivers/soc/qcom/Makefile
>> +++ b/drivers/soc/qcom/Makefile
>> @@ -4,6 +4,7 @@ obj-$(CONFIG_QCOM_AOSS_QMP) +=	qcom_aoss.o
>>   obj-$(CONFIG_QCOM_GENI_SE) +=	qcom-geni-se.o
>>   obj-$(CONFIG_QCOM_COMMAND_DB) += cmd-db.o
>>   obj-$(CONFIG_QCOM_CPR)		+= cpr.o
>> +obj-$(CONFIG_QCOM_EUD)          += qcom_eud.o
>>   obj-$(CONFIG_QCOM_GSBI)	+=	qcom_gsbi.o
>>   obj-$(CONFIG_QCOM_MDT_LOADER)	+= mdt_loader.o
>>   obj-$(CONFIG_QCOM_OCMEM)	+= ocmem.o
>> diff --git a/drivers/soc/qcom/qcom_eud.c b/drivers/soc/qcom/qcom_eud.c
>> new file mode 100644
>> index 0000000..613ac41
>> --- /dev/null
>> +++ b/drivers/soc/qcom/qcom_eud.c
>> @@ -0,0 +1,268 @@
>> +// SPDX-License-Identifier: GPL-2.0-only
>> +/*
>> + * Copyright (c) 2015-2021, The Linux Foundation. All rights reserved.
>> + */
>> +
>> +#include <linux/bitops.h>
>> +#include <linux/delay.h>
>> +#include <linux/err.h>
>> +#include <linux/interrupt.h>
>> +#include <linux/io.h>
>> +#include <linux/iopoll.h>
>> +#include <linux/kernel.h>
>> +#include <linux/module.h>
>> +#include <linux/of.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/slab.h>
>> +#include <linux/sysfs.h>
>> +#include <linux/usb/role.h>
>> +
>> +#define EUD_REG_INT1_EN_MASK	0x0024
>> +#define EUD_REG_INT_STATUS_1	0x0044
>> +#define EUD_REG_CTL_OUT_1	0x0074
>> +#define EUD_REG_VBUS_INT_CLR	0x0080
>> +#define EUD_REG_CSR_EUD_EN	0x1014
>> +#define EUD_REG_SW_ATTACH_DET	0x1018
>> +#define EUD_REG_EUD_EN2         0x0000
>> +
>> +#define EUD_ENABLE		BIT(0)
>> +#define EUD_INT_PET_EUD		BIT(0)
>> +#define EUD_INT_VBUS		BIT(2)
>> +#define EUD_INT_SAFE_MODE	BIT(4)
>> +#define EUD_INT_ALL		(EUD_INT_VBUS|EUD_INT_SAFE_MODE)
>> +
>> +struct eud_chip {
>> +	struct device			*dev;
>> +	struct usb_role_switch		*role_sw;
>> +	void __iomem			*eud_reg_base;
>> +	void __iomem			*eud_mode_mgr2_phys_base;
>> +	unsigned int			int_status;
>> +	int				eud_irq;
>> +	bool				enable;
>> +	bool				usb_attach;
>> +
>> +};
>> +
>> +static int enable_eud(struct eud_chip *priv)
>> +{
>> +	writel(EUD_ENABLE, priv->eud_reg_base + EUD_REG_CSR_EUD_EN);
>> +	writel(EUD_INT_VBUS | EUD_INT_SAFE_MODE,
>> +			priv->eud_reg_base + EUD_REG_INT1_EN_MASK);
>> +	writel(1, priv->eud_mode_mgr2_phys_base + EUD_REG_EUD_EN2);
>> +
>> +	return usb_role_switch_set_role(priv->role_sw, USB_ROLE_DEVICE);
>> +}
>> +
>> +static void disable_eud(struct eud_chip *priv)
>> +{
>> +	writel(0, priv->eud_reg_base + EUD_REG_CSR_EUD_EN);
>> +	writel(0, priv->eud_mode_mgr2_phys_base + EUD_REG_EUD_EN2);
>> +}
>> +
>> +static ssize_t enable_show(struct device *dev,
>> +		struct device_attribute *attr, char *buf)
>> +{
>> +	struct eud_chip *chip = dev_get_drvdata(dev);
>> +
>> +	return sysfs_emit(buf, "%d\n", chip->enable);
>> +}
>> +
>> +static ssize_t enable_store(struct device *dev,
>> +		struct device_attribute *attr,
>> +		const char *buf, size_t count)
>> +{
>> +	struct eud_chip *chip = dev_get_drvdata(dev);
>> +	bool enable;
>> +	int ret;
>> +
>> +	if (kstrtobool(buf, &enable))
>> +		return -EINVAL;
>> +
>> +	if (enable) {
>> +		ret = enable_eud(chip);
>> +		if (!ret)
>> +			chip->enable = enable;
>> +	} else {
>> +		disable_eud(chip);
>> +	}
>> +
>> +	return count;
>> +}
>> +
>> +static DEVICE_ATTR_RW(enable);
>> +
>> +static struct attribute *eud_attrs[] = {
>> +	&dev_attr_enable.attr,
>> +	NULL,
>> +};
>> +
>> +static struct attribute_group attr_group = {
>> +	.attrs = eud_attrs,
>> +};
>> +
>> +static const struct attribute_group *attr_groups[] = {
>> +	&attr_group,
>> +	NULL
>> +};
> ATTRIBUTE_GROUPS()?
Ack
>
> thanks,
>
> greg k-h

Re: [PATCH V2 6/8] arm64: dts: qcom: sc7280: Add EUD dt node and dwc3 connector

[Rob Herring]

On Thu, Dec 02, 2021 at 03:21:25PM +0530, Souradeep Chowdhury wrote:
> Add the Embedded USB Debugger(EUD) device tree node. The
> node contains EUD base register region and EUD mode
> manager register regions along with the interrupt entry.
> Also add the connector to EUD which is mapped as the child
> of dwc3. The connector is attached to EUD via port. Also add
> the role-switch property to dwc3 node.
> 
> Signed-off-by: Souradeep Chowdhury <quic_schowdhu@quicinc.com>
> ---
>  arch/arm64/boot/dts/qcom/sc7280.dtsi | 25 +++++++++++++++++++++++++
>  1 file changed, 25 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/qcom/sc7280.dtsi b/arch/arm64/boot/dts/qcom/sc7280.dtsi
> index 53a21d0..2d14e5c 100644
> --- a/arch/arm64/boot/dts/qcom/sc7280.dtsi
> +++ b/arch/arm64/boot/dts/qcom/sc7280.dtsi
> @@ -1315,6 +1315,18 @@
>  				phys = <&usb_2_hsphy>;
>  				phy-names = "usb2-phy";
>  				maximum-speed = "high-speed";
> +				usb-role-switch;
> +				usb_con: eud_usb_connector {
> +					compatible = "qcom,usb-connector-eud",
> +						     "usb-c-connector";
> +					ports {
> +						port@0 {

It is already defined that port@0 of the connector is USB HS data. Is 
that the case here? What about the SS lines?

From the description, it sounds like the data path is DWC3 -> EUD -> 
connector. The DT structure doesn't match that.

> +							usb2_role_switch: endpoint {
> +								remote-endpoint = <&eud_ep>;
> +							};
> +						};
> +					};
> +				};
>  			};
>  		};
>  
> @@ -1339,6 +1351,19 @@
>  			interrupts = <GIC_SPI 582 IRQ_TYPE_LEVEL_HIGH>;
>  		};
>  
> +		eud:  eud@88e0000 {
> +			compatible = "qcom,sc7280-eud","qcom,eud";
> +			reg = <0 0x88e0000 0 0x2000>,
> +			      <0 0x88e2000 0 0x1000>;
> +			interrupt-parent = <&pdc>;
> +			interrupts = <11 IRQ_TYPE_LEVEL_HIGH>;
> +			port {
> +				eud_ep: endpoint {
> +					remote-endpoint = <&usb2_role_switch>;
> +				};
> +			};
> +		};
> +
>  		nsp_noc: interconnect@a0c0000 {
>  			reg = <0 0x0a0c0000 0 0x10000>;
>  			compatible = "qcom,sc7280-nsp-noc";
> -- 
> 2.7.4
> 
> 

Re: [PATCH V2 4/8] usb: dwc3: drd: Register the eud connector child node for dwc3

[Rob Herring]

On Thu, Dec 02, 2021 at 03:21:23PM +0530, Souradeep Chowdhury wrote:
> Register the child node for dwc3 which is the "eud_usb_connector".
> The eud driver will be able to switch the usb role from device to
> host and vice versa using the role switch property of dwc3 node.
> 
> Signed-off-by: Souradeep Chowdhury <quic_schowdhu@quicinc.com>
> ---
>  drivers/usb/dwc3/drd.c | 26 ++++++++++++++++++++++++++
>  1 file changed, 26 insertions(+)
> 
> diff --git a/drivers/usb/dwc3/drd.c b/drivers/usb/dwc3/drd.c
> index d7f7683..b4ea55c 100644
> --- a/drivers/usb/dwc3/drd.c
> +++ b/drivers/usb/dwc3/drd.c
> @@ -8,6 +8,7 @@
>   */
>  
>  #include <linux/extcon.h>
> +#include <linux/of_platform.h>
>  #include <linux/of_graph.h>
>  #include <linux/platform_device.h>
>  #include <linux/property.h>
> @@ -164,6 +165,27 @@ static int dwc3_otg_get_irq(struct dwc3 *dwc)
>  	return irq;
>  }
>  
> +static int dwc3_register_eud(struct dwc3 *dwc)
> +{
> +	struct device		*dev = dwc->dev;
> +	struct device_node	*np = dev->of_node;
> +	int                     ret;
> +
> +	of_get_child_by_name(np, "eud_usb_connector");

Connector nodes are named 'connector' or possibly 'usb-connector'. If 
you are creating an ABI with the node name, it should be documented. 
However, it's preferred to use 'compatible' for identifying nodes rather 
than a node name.

> +	if (!np) {
> +		dev_dbg(dev, "no usb_connector child node specified\n");
> +		return 0;
> +	}
> +
> +	ret = of_platform_populate(np, NULL, NULL, dev);

But why is any of this needed. The connector doesn't have a driver (I 
expect eventually we will) and the EUD device is not a child.

> +	if (ret) {
> +		dev_err(dev, "failed to register usb_connector - %d\n", ret);
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
>  void dwc3_otg_init(struct dwc3 *dwc)
>  {
>  	u32 reg;
> @@ -580,6 +602,10 @@ int dwc3_drd_init(struct dwc3 *dwc)
>  		ret = dwc3_setup_role_switch(dwc);
>  		if (ret < 0)
>  			return ret;
> +
> +		ret = dwc3_register_eud(dwc);
> +		if (ret < 0)
> +			return ret;
>  	} else if (dwc->edev) {
>  		dwc->edev_nb.notifier_call = dwc3_drd_notifier;
>  		ret = extcon_register_notifier(dwc->edev, EXTCON_USB_HOST,
> -- 
> 2.7.4
> 
> 

Re: [PATCH V2 4/8] usb: dwc3: drd: Register the eud connector child node for dwc3

[Souradeep Chowdhury]

On 12/14/2021 1:33 AM, Rob Herring wrote:
> On Thu, Dec 02, 2021 at 03:21:23PM +0530, Souradeep Chowdhury wrote:
>> Register the child node for dwc3 which is the "eud_usb_connector".
>> The eud driver will be able to switch the usb role from device to
>> host and vice versa using the role switch property of dwc3 node.
>>
>> Signed-off-by: Souradeep Chowdhury <quic_schowdhu@quicinc.com>
>> ---
>>   drivers/usb/dwc3/drd.c | 26 ++++++++++++++++++++++++++
>>   1 file changed, 26 insertions(+)
>>
>> diff --git a/drivers/usb/dwc3/drd.c b/drivers/usb/dwc3/drd.c
>> index d7f7683..b4ea55c 100644
>> --- a/drivers/usb/dwc3/drd.c
>> +++ b/drivers/usb/dwc3/drd.c
>> @@ -8,6 +8,7 @@
>>    */
>>   
>>   #include <linux/extcon.h>
>> +#include <linux/of_platform.h>
>>   #include <linux/of_graph.h>
>>   #include <linux/platform_device.h>
>>   #include <linux/property.h>
>> @@ -164,6 +165,27 @@ static int dwc3_otg_get_irq(struct dwc3 *dwc)
>>   	return irq;
>>   }
>>   
>> +static int dwc3_register_eud(struct dwc3 *dwc)
>> +{
>> +	struct device		*dev = dwc->dev;
>> +	struct device_node	*np = dev->of_node;
>> +	int                     ret;
>> +
>> +	of_get_child_by_name(np, "eud_usb_connector");
> Connector nodes are named 'connector' or possibly 'usb-connector'. If
> you are creating an ABI with the node name, it should be documented.
> However, it's preferred to use 'compatible' for identifying nodes rather
> than a node name.
Ack.
>> +	if (!np) {
>> +		dev_dbg(dev, "no usb_connector child node specified\n");
>> +		return 0;
>> +	}
>> +
>> +	ret = of_platform_populate(np, NULL, NULL, dev);
> But why is any of this needed. The connector doesn't have a driver (I
> expect eventually we will) and the EUD device is not a child.

Ack. This can be removed as we are no longer mapping EUD as a type C 
connector.


>> +	if (ret) {
>> +		dev_err(dev, "failed to register usb_connector - %d\n", ret);
>> +		return ret;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>>   void dwc3_otg_init(struct dwc3 *dwc)
>>   {
>>   	u32 reg;
>> @@ -580,6 +602,10 @@ int dwc3_drd_init(struct dwc3 *dwc)
>>   		ret = dwc3_setup_role_switch(dwc);
>>   		if (ret < 0)
>>   			return ret;
>> +
>> +		ret = dwc3_register_eud(dwc);
>> +		if (ret < 0)
>> +			return ret;
>>   	} else if (dwc->edev) {
>>   		dwc->edev_nb.notifier_call = dwc3_drd_notifier;
>>   		ret = extcon_register_notifier(dwc->edev, EXTCON_USB_HOST,
>> -- 
>> 2.7.4
>>
>>

Re: [PATCH V2 6/8] arm64: dts: qcom: sc7280: Add EUD dt node and dwc3 connector

[Souradeep Chowdhury]

On 12/14/2021 1:29 AM, Rob Herring wrote:
> On Thu, Dec 02, 2021 at 03:21:25PM +0530, Souradeep Chowdhury wrote:
>> Add the Embedded USB Debugger(EUD) device tree node. The
>> node contains EUD base register region and EUD mode
>> manager register regions along with the interrupt entry.
>> Also add the connector to EUD which is mapped as the child
>> of dwc3. The connector is attached to EUD via port. Also add
>> the role-switch property to dwc3 node.
>>
>> Signed-off-by: Souradeep Chowdhury <quic_schowdhu@quicinc.com>
>> ---
>>   arch/arm64/boot/dts/qcom/sc7280.dtsi | 25 +++++++++++++++++++++++++
>>   1 file changed, 25 insertions(+)
>>
>> diff --git a/arch/arm64/boot/dts/qcom/sc7280.dtsi b/arch/arm64/boot/dts/qcom/sc7280.dtsi
>> index 53a21d0..2d14e5c 100644
>> --- a/arch/arm64/boot/dts/qcom/sc7280.dtsi
>> +++ b/arch/arm64/boot/dts/qcom/sc7280.dtsi
>> @@ -1315,6 +1315,18 @@
>>   				phys = <&usb_2_hsphy>;
>>   				phy-names = "usb2-phy";
>>   				maximum-speed = "high-speed";
>> +				usb-role-switch;
>> +				usb_con: eud_usb_connector {
>> +					compatible = "qcom,usb-connector-eud",
>> +						     "usb-c-connector";
>> +					ports {
>> +						port@0 {
> It is already defined that port@0 of the connector is USB HS data. Is
> that the case here? What about the SS lines?

As per the yaml documentation this is to be used for USB HS lines but in 
this case I am using the port to get the connector fwnode from the eud 
driver and then perform the role switch from the connector parent which 
is the dwc3 controller.  Should I update the yaml file to include this 
description?

>  From the description, it sounds like the data path is DWC3 -> EUD ->
> connector. The DT structure doesn't match that.

EUD is an independent QCOM IP , it is a mini usb hub which can only 
function in device mode. That's why it has been mapped as a separate 
device tree node connected to the type c connector via port endpoint to 
perform a role switch when necessary. I have kept EUD and connector at 
the same level as there is no direct data path from EUD to the connector 
and both are at a level below the controller.

>
>> +							usb2_role_switch: endpoint {
>> +								remote-endpoint = <&eud_ep>;
>> +							};
>> +						};
>> +					};
>> +				};
>>   			};
>>   		};
>>   
>> @@ -1339,6 +1351,19 @@
>>   			interrupts = <GIC_SPI 582 IRQ_TYPE_LEVEL_HIGH>;
>>   		};
>>   
>> +		eud:  eud@88e0000 {
>> +			compatible = "qcom,sc7280-eud","qcom,eud";
>> +			reg = <0 0x88e0000 0 0x2000>,
>> +			      <0 0x88e2000 0 0x1000>;
>> +			interrupt-parent = <&pdc>;
>> +			interrupts = <11 IRQ_TYPE_LEVEL_HIGH>;
>> +			port {
>> +				eud_ep: endpoint {
>> +					remote-endpoint = <&usb2_role_switch>;
>> +				};
>> +			};
>> +		};
>> +
>>   		nsp_noc: interconnect@a0c0000 {
>>   			reg = <0 0x0a0c0000 0 0x10000>;
>>   			compatible = "qcom,sc7280-nsp-noc";
>> -- 
>> 2.7.4
>>
>>