[PATCH V5 0/9] Add USB3.0 and TI HD3SS3220 driver support

[PATCH V5 0/9] Add USB3.0 and TI HD3SS3220 driver support

[Biju Das]

This series adds USB 3.0 support for the CAT874 platform, including a
new driver for the TI HD3SS3220 USB Type-C DRP port controller.

This patch series supports:
1) Host hotplug operation
2) Device hot plug operation
3) USB type-C data_role switch
   (Tested with 2 RZ/G2E boards connected with a Type-C cable)

This patchset is based on linux_next next-20190423 branch.
V4-->V5
  * Incorporated Heikki's review comment.
    (https://patchwork.kernel.org/patch/10902531/)
  * Patch 1 is a dependency patch to make the compilation successful.
    (https://patchwork.kernel.org/patch/10909971/)
  * Patch 2 is also dependency patch to make the compilation successful.
    Rebased on top of Patch1 and fixed Heikki's review comments
    (https://patchwork.kernel.org/patch/10882555/)
  * Incorporated Shimoda-San's review comment.
    (https://patchwork.kernel.org/patch/10902535/)
V3-->V4
  * Incorporated Chunfeng Yun's review comment
    (https://patchwork.kernel.org/project/linux-usb/list/?submitter=133171)
  * Used fwnode API's to get roleswitch handle

V2-->V3
  * Used the new API to usb_role_switch by node to find the remote endpoint
    (https://patchwork.kernel.org/patch/10882555/)
  * Added renesas,usb-role-switch property
  * Incorporated shimoda-san's review comment
    (https://patchwork.kernel.org/patch/10852507/)

V1-->V2
  * Use USB role class instead of extcon to receive connect and disconnect
    events and also for the dual role switch.
  * Dropped patch 6
  * Squashed patch 8 and patch 9
  * https://patchwork.kernel.org/cover/10840641/


Biju Das (7):
  dt-bindings: usb: hd3ss3220 device tree binding document
  dt-bindings: usb: renesas_usb3: Add renesas,usb-role-switch property
  usb: typec: driver for TI HD3SS3220 USB Type-C DRP port controller
  usb: gadget: udc: renesas_usb3: Use usb_role_switch framework
  arm64: defconfig: enable TYPEC_HD3SS3220 config option
  arm64: dts: renesas: r8a774c0-cat874: Enable USB3.0 host/peripheral
    device node
  arm64: dts: renesas: r8a774c0-cat874: Enable usb role switch support

Chunfeng Yun (1):
  usb: roles: add API to get usb_role_switch by node

Yu Chen (1):
  usb: roles: Introduce stubs for the exiting functions in role.h.

 .../devicetree/bindings/usb/renesas_usb3.txt       |  22 ++
 .../devicetree/bindings/usb/ti,hd3ss3220.txt       |  37 +++
 arch/arm64/boot/dts/renesas/r8a774c0-cat874.dts    |  56 +++++
 arch/arm64/configs/defconfig                       |   2 +
 drivers/usb/gadget/udc/renesas_usb3.c              |  92 ++++++-
 drivers/usb/roles/class.c                          |  25 ++
 drivers/usb/typec/Kconfig                          |  10 +
 drivers/usb/typec/Makefile                         |   1 +
 drivers/usb/typec/hd3ss3220.c                      | 263 +++++++++++++++++++++
 include/linux/usb/role.h                           |  38 +++
 10 files changed, 539 insertions(+), 7 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/usb/ti,hd3ss3220.txt
 create mode 100644 drivers/usb/typec/hd3ss3220.c

-- 
2.7.4

[PATCH V5 1/9] usb: roles: Introduce stubs for the exiting functions in role.h.

[Biju Das]

From: Yu Chen <chenyu56@huawei.com>

This patch adds stubs for the exiting functions while
CONFIG_USB_ROLE_SWITCH does not enabled.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: John Stultz <john.stultz@linaro.org>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Yu Chen <chenyu56@huawei.com>
---
 * This is a dependency patch for the next patch in this series
   Ref:(https://patchwork.kernel.org/patch/10909971/)
 
 Note:- This patch is added to this series to avoid compilation issues.
---
 include/linux/usb/role.h | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/include/linux/usb/role.h b/include/linux/usb/role.h
index c05ffa6..da2b964 100644
--- a/include/linux/usb/role.h
+++ b/include/linux/usb/role.h
@@ -42,6 +42,8 @@ struct usb_role_switch_desc {
 	bool allow_userspace_control;
 };
 
+
+#if IS_ENABLED(CONFIG_USB_ROLE_SWITCH)
 int usb_role_switch_set_role(struct usb_role_switch *sw, enum usb_role role);
 enum usb_role usb_role_switch_get_role(struct usb_role_switch *sw);
 struct usb_role_switch *usb_role_switch_get(struct device *dev);
@@ -51,5 +53,33 @@ struct usb_role_switch *
 usb_role_switch_register(struct device *parent,
 			 const struct usb_role_switch_desc *desc);
 void usb_role_switch_unregister(struct usb_role_switch *sw);
+#else
+static inline int usb_role_switch_set_role(struct usb_role_switch *sw,
+		enum usb_role role)
+{
+	return 0;
+}
+
+static inline enum usb_role usb_role_switch_get_role(struct usb_role_switch *sw)
+{
+	return USB_ROLE_NONE;
+}
+
+static inline struct usb_role_switch *usb_role_switch_get(struct device *dev)
+{
+	return ERR_PTR(-ENODEV);
+}
+
+static inline void usb_role_switch_put(struct usb_role_switch *sw) { }
+
+static inline struct usb_role_switch *
+usb_role_switch_register(struct device *parent,
+			 const struct usb_role_switch_desc *desc)
+{
+	return ERR_PTR(-ENODEV);
+}
+
+static inline void usb_role_switch_unregister(struct usb_role_switch *sw) { }
+#endif
 
 #endif /* __LINUX_USB_ROLE_H */
-- 
2.7.4

[PATCH V5 2/9] usb: roles: add API to get usb_role_switch by node

[Biju Das]

From: Chunfeng Yun <chunfeng.yun@mediatek.com>

Add fwnode_usb_role_switch_get() to make easier to get
usb_role_switch by fwnode which register it.
It's useful when there is not device_connection registered
between two drivers and only knows the fwnode which register
usb_role_switch.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Biju Das <biju.das@bp.renesas.com>
---
 * Rebased on top of patch1 in this series. Incorporated Heikki's review comments
   (https://patchwork.kernel.org/patch/10882555/)

 Note:- This patch is added to this series to avoid compilation issues.
---
 drivers/usb/roles/class.c | 25 +++++++++++++++++++++++++
 include/linux/usb/role.h  |  8 ++++++++
 2 files changed, 33 insertions(+)

diff --git a/drivers/usb/roles/class.c b/drivers/usb/roles/class.c
index f45d8df..a0847a8 100644
--- a/drivers/usb/roles/class.c
+++ b/drivers/usb/roles/class.c
@@ -136,6 +136,31 @@ struct usb_role_switch *usb_role_switch_get(struct device *dev)
 EXPORT_SYMBOL_GPL(usb_role_switch_get);
 
 /**
+ * fwnode_usb_role_switch_get - Find USB role switch by it's parent fwnode
+ * @fwnode: The fwnode that register USB role switch
+ *
+ * Finds and returns role switch registered by @fwnode. The reference count
+ * for the found switch is incremented.
+ */
+struct usb_role_switch *
+fwnode_usb_role_switch_get(struct fwnode_handle *fwnode)
+{
+	struct usb_role_switch *sw;
+	struct device *dev;
+
+	dev = class_find_device(role_class, NULL, fwnode,
+				switch_fwnode_match);
+	if (!dev)
+		return ERR_PTR(-EPROBE_DEFER);
+
+	sw = to_role_switch(dev);
+	WARN_ON(!try_module_get(sw->dev.parent->driver->owner));
+
+	return sw;
+}
+EXPORT_SYMBOL_GPL(fwnode_usb_role_switch_get);
+
+/**
  * usb_role_switch_put - Release handle to a switch
  * @sw: USB Role Switch
  *
diff --git a/include/linux/usb/role.h b/include/linux/usb/role.h
index da2b964..0f6e2829 100644
--- a/include/linux/usb/role.h
+++ b/include/linux/usb/role.h
@@ -47,6 +47,8 @@ struct usb_role_switch_desc {
 int usb_role_switch_set_role(struct usb_role_switch *sw, enum usb_role role);
 enum usb_role usb_role_switch_get_role(struct usb_role_switch *sw);
 struct usb_role_switch *usb_role_switch_get(struct device *dev);
+struct usb_role_switch *
+fwnode_usb_role_switch_get(struct fwnode_handle *fwnode);
 void usb_role_switch_put(struct usb_role_switch *sw);
 
 struct usb_role_switch *
@@ -70,6 +72,12 @@ static inline struct usb_role_switch *usb_role_switch_get(struct device *dev)
 	return ERR_PTR(-ENODEV);
 }
 
+struct usb_role_switch *
+fwnode_usb_role_switch_get(struct fwnode_handle *fwnode)
+{
+	return ERR_PTR(-ENODEV);
+}
+
 static inline void usb_role_switch_put(struct usb_role_switch *sw) { }
 
 static inline struct usb_role_switch *
-- 
2.7.4

[PATCH V5 3/9] dt-bindings: usb: hd3ss3220 device tree binding document

[Biju Das]

Add device tree binding document for TI HD3SS3220 Type-C DRP port
controller driver.

Signed-off-by: Biju Das <biju.das@bp.renesas.com>
Reviewed-by: Rob Herring <robh@kernel.org>
---
V4-->V5
  * No Change.
V3-->V4
  * No Change.
V2-->V3
  * Added Rob's Reviewed by tag.
V1-->V2
  * Added connector node.
  * updated the example with connector node.
---
 .../devicetree/bindings/usb/ti,hd3ss3220.txt       | 37 ++++++++++++++++++++++
 1 file changed, 37 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/usb/ti,hd3ss3220.txt

diff --git a/Documentation/devicetree/bindings/usb/ti,hd3ss3220.txt b/Documentation/devicetree/bindings/usb/ti,hd3ss3220.txt
new file mode 100644
index 0000000..7f41400
--- /dev/null
+++ b/Documentation/devicetree/bindings/usb/ti,hd3ss3220.txt
@@ -0,0 +1,37 @@
+TI HD3SS3220 TypeC DRP Port Controller.
+
+Required properties:
+ - compatible: Must be "ti,hd3ss3220".
+ - reg: I2C slave address, must be 0x47 or 0x67 based on ADDR pin.
+ - interrupts: <a b> where a is the interrupt number and b represents an
+   encoding of the sense and level information for the interrupt.
+
+Required sub-node:
+ - connector : The "usb-c-connector" attached to the hd3ss3220 chip. The
+   bindings of the connector node are specified in:
+
+	Documentation/devicetree/bindings/connector/usb-connector.txt
+
+Example:
+hd3ss3220@47 {
+	compatible = "ti,hd3ss3220";
+	reg = <0x47>;
+	interrupt-parent = <&gpio6>;
+	interrupts = <3 IRQ_TYPE_LEVEL_LOW>;
+
+	usb_con: connector {
+		compatible = "usb-c-connector";
+		label = "USB-C";
+		data-role = "dual";
+	};
+
+	port {
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		hd3ss3220_ep: endpoint@0 {
+			reg = <0>;
+			remote-endpoint = <&usb3peri_role_switch>;
+		};
+	};
+};
-- 
2.7.4

[PATCH V5 4/9] dt-bindings: usb: renesas_usb3: Add renesas,usb-role-switch property

[Biju Das]

Add an optional property renesas,usb-role-switch to support
dual role switch for USB Type-C DRP port controller devices
using USB role switch class framework.

Signed-off-by: Biju Das <biju.das@bp.renesas.com>
---
 V4-->V5
  * No Change
 V3-->V4
  * No Change
 V2-->V3
  * Added optional renesas,usb-role-switch property.
 V1-->V2
  * Added usb-role-switch-property
  * Updated the example with usb-role-switch property.
---
 .../devicetree/bindings/usb/renesas_usb3.txt       | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/Documentation/devicetree/bindings/usb/renesas_usb3.txt b/Documentation/devicetree/bindings/usb/renesas_usb3.txt
index 35039e7..f1cb06a 100644
--- a/Documentation/devicetree/bindings/usb/renesas_usb3.txt
+++ b/Documentation/devicetree/bindings/usb/renesas_usb3.txt
@@ -22,6 +22,7 @@ Required properties:
 Optional properties:
   - phys: phandle + phy specifier pair
   - phy-names: must be "usb"
+  - renesas,usb-role-switch: use USB role switch to handle role switch events
 
 Example of R-Car H3 ES1.x:
 	usb3_peri0: usb@ee020000 {
@@ -39,3 +40,24 @@ Example of R-Car H3 ES1.x:
 		interrupts = <GIC_SPI 100 IRQ_TYPE_LEVEL_HIGH>;
 		clocks = <&cpg CPG_MOD 327>;
 	};
+
+Example of RZ/G2E:
+	usb3_peri0: usb@ee020000 {
+		compatible = "renesas,r8a774c0-usb3-peri",
+			     "renesas,rcar-gen3-usb3-peri";
+		reg = <0 0xee020000 0 0x400>;
+		interrupts = <GIC_SPI 104 IRQ_TYPE_LEVEL_HIGH>;
+		clocks = <&cpg CPG_MOD 328>;
+		companion = <&xhci0>;
+		renesas,usb-role-switch;
+
+		port {
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			usb3peri_role_switch: endpoint@0 {
+				reg = <0>;
+				remote-endpoint = <&hd3ss3220_ep>;
+			};
+		};
+	};
-- 
2.7.4

[PATCH V5 5/9] usb: typec: driver for TI HD3SS3220 USB Type-C DRP port controller

[Biju Das]

Driver for TI HD3SS3220 USB Type-C DRP port controller.

The driver currently registers the port and supports data role swapping.

Signed-off-by: Biju Das <biju.das@bp.renesas.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
---
 V4-->V5
   * Incorporated Heikki's review comment
     (https://patchwork.kernel.org/patch/10902531/)
   * Added Heikki's Reviewed-by tag
 V3-->V4
   * Incorporated Chunfeng Yun's review comment
   * Used fwnode API's to get usb role switch handle.
 
 V2-->V3
   * Used the new api "usb_role_switch by node" for getting
     remote endpoint associated with Type-C USB DRP port
     controller devices.
 V1-->V2
   * Driver uses usb role class instead of extcon for dual role switch
     and also handles connect/disconnect events.
---
 drivers/usb/typec/Kconfig     |  10 ++
 drivers/usb/typec/Makefile    |   1 +
 drivers/usb/typec/hd3ss3220.c | 263 ++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 274 insertions(+)
 create mode 100644 drivers/usb/typec/hd3ss3220.c

diff --git a/drivers/usb/typec/Kconfig b/drivers/usb/typec/Kconfig
index 89d9193..92a3717 100644
--- a/drivers/usb/typec/Kconfig
+++ b/drivers/usb/typec/Kconfig
@@ -50,6 +50,16 @@ source "drivers/usb/typec/tcpm/Kconfig"
 
 source "drivers/usb/typec/ucsi/Kconfig"
 
+config TYPEC_HD3SS3220
+	tristate "TI HD3SS3220 Type-C DRP Port controller driver"
+	depends on I2C
+	help
+	  Say Y or M here if your system has TI HD3SS3220 Type-C DRP Port
+	  controller driver.
+
+	  If you choose to build this driver as a dynamically linked module, the
+	  module will be called hd3ss3220.ko.
+
 config TYPEC_TPS6598X
 	tristate "TI TPS6598x USB Power Delivery controller driver"
 	depends on I2C
diff --git a/drivers/usb/typec/Makefile b/drivers/usb/typec/Makefile
index 6696b72..7753a5c3 100644
--- a/drivers/usb/typec/Makefile
+++ b/drivers/usb/typec/Makefile
@@ -4,5 +4,6 @@ typec-y				:= class.o mux.o bus.o
 obj-$(CONFIG_TYPEC)		+= altmodes/
 obj-$(CONFIG_TYPEC_TCPM)	+= tcpm/
 obj-$(CONFIG_TYPEC_UCSI)	+= ucsi/
+obj-$(CONFIG_TYPEC_HD3SS3220)	+= hd3ss3220.o
 obj-$(CONFIG_TYPEC_TPS6598X)	+= tps6598x.o
 obj-$(CONFIG_TYPEC)		+= mux/
diff --git a/drivers/usb/typec/hd3ss3220.c b/drivers/usb/typec/hd3ss3220.c
new file mode 100644
index 0000000..7ef7e85
--- /dev/null
+++ b/drivers/usb/typec/hd3ss3220.c
@@ -0,0 +1,263 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * TI HD3SS3220 Type-C DRP Port Controller Driver
+ *
+ * Copyright (C) 2019 Renesas Electronics Corp.
+ */
+
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/usb/role.h>
+#include <linux/irqreturn.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+#include <linux/usb/typec.h>
+#include <linux/delay.h>
+
+#define HD3SS3220_REG_CN_STAT_CTRL	0x09
+#define HD3SS3220_REG_GEN_CTRL		0x0A
+#define HD3SS3220_REG_DEV_REV		0xA0
+
+/* Register HD3SS3220_REG_CN_STAT_CTRL*/
+#define HD3SS3220_REG_CN_STAT_CTRL_ATTACHED_STATE_MASK	(BIT(7) | BIT(6))
+#define HD3SS3220_REG_CN_STAT_CTRL_AS_DFP		BIT(6)
+#define HD3SS3220_REG_CN_STAT_CTRL_AS_UFP		BIT(7)
+#define HD3SS3220_REG_CN_STAT_CTRL_TO_ACCESSORY		(BIT(7) | BIT(6))
+#define HD3SS3220_REG_CN_STAT_CTRL_INT_STATUS		BIT(4)
+
+/* Register HD3SS3220_REG_GEN_CTRL*/
+#define HD3SS3220_REG_GEN_CTRL_SRC_PREF_MASK		(BIT(2) | BIT(1))
+#define HD3SS3220_REG_GEN_CTRL_SRC_PREF_DRP_DEFAULT	0x00
+#define HD3SS3220_REG_GEN_CTRL_SRC_PREF_DRP_TRY_SNK	BIT(1)
+#define HD3SS3220_REG_GEN_CTRL_SRC_PREF_DRP_TRY_SRC	(BIT(2) | BIT(1))
+
+struct hd3ss3220 {
+	struct device *dev;
+	struct regmap *regmap;
+	struct usb_role_switch	*role_sw;
+	struct typec_port *port;
+	struct typec_capability typec_cap;
+};
+
+static int hd3ss3220_set_source_pref(struct hd3ss3220 *hd3ss3220, int src_pref)
+{
+	return regmap_update_bits(hd3ss3220->regmap, HD3SS3220_REG_GEN_CTRL,
+				  HD3SS3220_REG_GEN_CTRL_SRC_PREF_MASK,
+				  src_pref);
+}
+
+static enum usb_role hd3ss3220_get_attached_state(struct hd3ss3220 *hd3ss3220)
+{
+	unsigned int reg_val;
+	enum usb_role attached_state;
+	int ret;
+
+	ret = regmap_read(hd3ss3220->regmap, HD3SS3220_REG_CN_STAT_CTRL,
+			  &reg_val);
+	if (ret < 0)
+		return ret;
+
+	switch (reg_val & HD3SS3220_REG_CN_STAT_CTRL_ATTACHED_STATE_MASK) {
+	case HD3SS3220_REG_CN_STAT_CTRL_AS_DFP:
+		attached_state = USB_ROLE_HOST;
+		break;
+	case HD3SS3220_REG_CN_STAT_CTRL_AS_UFP:
+		attached_state = USB_ROLE_DEVICE;
+		break;
+	default:
+		attached_state = USB_ROLE_NONE;
+		break;
+	}
+
+	return attached_state;
+}
+
+static int hd3ss3220_dr_set(const struct typec_capability *cap,
+			    enum typec_data_role role)
+{
+	struct hd3ss3220 *hd3ss3220 = container_of(cap, struct hd3ss3220,
+						   typec_cap);
+	enum usb_role role_val;
+	int pref, ret = 0;
+
+	if (role == TYPEC_HOST) {
+		role_val = USB_ROLE_HOST;
+		pref = HD3SS3220_REG_GEN_CTRL_SRC_PREF_DRP_TRY_SRC;
+	} else {
+		role_val = USB_ROLE_DEVICE;
+		pref = HD3SS3220_REG_GEN_CTRL_SRC_PREF_DRP_TRY_SNK;
+	}
+
+	ret = hd3ss3220_set_source_pref(hd3ss3220, pref);
+	usleep_range(10, 100);
+
+	usb_role_switch_set_role(hd3ss3220->role_sw, role_val);
+	typec_set_data_role(hd3ss3220->port, role);
+
+	return ret;
+}
+
+static void hd3ss3220_set_role(struct hd3ss3220 *hd3ss3220)
+{
+	enum usb_role role_state = hd3ss3220_get_attached_state(hd3ss3220);
+
+	usb_role_switch_set_role(hd3ss3220->role_sw, role_state);
+	if (role_state == USB_ROLE_NONE)
+		hd3ss3220_set_source_pref(hd3ss3220,
+				HD3SS3220_REG_GEN_CTRL_SRC_PREF_DRP_DEFAULT);
+
+	switch (role_state) {
+	case USB_ROLE_HOST:
+		typec_set_data_role(hd3ss3220->port, TYPEC_HOST);
+		break;
+	case USB_ROLE_DEVICE:
+		typec_set_data_role(hd3ss3220->port, TYPEC_DEVICE);
+		break;
+	default:
+		break;
+	}
+}
+
+irqreturn_t hd3ss3220_irq(struct hd3ss3220 *hd3ss3220)
+{
+	int err;
+
+	hd3ss3220_set_role(hd3ss3220);
+	err = regmap_update_bits_base(hd3ss3220->regmap,
+				      HD3SS3220_REG_CN_STAT_CTRL,
+				      HD3SS3220_REG_CN_STAT_CTRL_INT_STATUS,
+				      HD3SS3220_REG_CN_STAT_CTRL_INT_STATUS,
+				      NULL, false, true);
+	if (err < 0)
+		return IRQ_NONE;
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t hd3ss3220_irq_handler(int irq, void *data)
+{
+	struct i2c_client *client = to_i2c_client(data);
+	struct hd3ss3220 *hd3ss3220 = i2c_get_clientdata(client);
+
+	return hd3ss3220_irq(hd3ss3220);
+}
+
+static const struct regmap_config config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.max_register = 0x0A,
+};
+
+static int hd3ss3220_probe(struct i2c_client *client,
+		const struct i2c_device_id *id)
+{
+	struct hd3ss3220 *hd3ss3220;
+	struct fwnode_handle *parent, *child;
+	int ret;
+	unsigned int data;
+
+	hd3ss3220 = devm_kzalloc(&client->dev, sizeof(struct hd3ss3220),
+				 GFP_KERNEL);
+	if (!hd3ss3220)
+		return -ENOMEM;
+
+	i2c_set_clientdata(client, hd3ss3220);
+
+	hd3ss3220->dev = &client->dev;
+	hd3ss3220->regmap = devm_regmap_init_i2c(client, &config);
+	if (IS_ERR(hd3ss3220->regmap))
+		return PTR_ERR(hd3ss3220->regmap);
+
+	hd3ss3220_set_source_pref(hd3ss3220,
+				  HD3SS3220_REG_GEN_CTRL_SRC_PREF_DRP_DEFAULT);
+	child = fwnode_graph_get_next_endpoint(dev_fwnode(hd3ss3220->dev),
+					       NULL);
+	parent = fwnode_graph_get_remote_port_parent(child);
+	hd3ss3220->role_sw = fwnode_usb_role_switch_get(parent);
+	if (IS_ERR_OR_NULL(hd3ss3220->role_sw)) {
+		fwnode_handle_put(child);
+		fwnode_handle_put(parent);
+		return PTR_ERR(hd3ss3220->role_sw);
+	}
+
+	fwnode_handle_put(child);
+	fwnode_handle_put(parent);
+
+	hd3ss3220->typec_cap.prefer_role = TYPEC_NO_PREFERRED_ROLE;
+	hd3ss3220->typec_cap.dr_set = hd3ss3220_dr_set;
+	hd3ss3220->typec_cap.type = TYPEC_PORT_DRP;
+	hd3ss3220->typec_cap.data = TYPEC_PORT_DRD;
+
+	hd3ss3220->port = typec_register_port(&client->dev,
+					      &hd3ss3220->typec_cap);
+	if (IS_ERR(hd3ss3220->port))
+		return PTR_ERR(hd3ss3220->port);
+
+	hd3ss3220_set_role(hd3ss3220);
+	ret = regmap_read(hd3ss3220->regmap, HD3SS3220_REG_CN_STAT_CTRL, &data);
+	if (ret < 0)
+		goto error;
+
+	if (data & HD3SS3220_REG_CN_STAT_CTRL_INT_STATUS) {
+		ret = regmap_write(hd3ss3220->regmap,
+				HD3SS3220_REG_CN_STAT_CTRL,
+				data | HD3SS3220_REG_CN_STAT_CTRL_INT_STATUS);
+		if (ret < 0)
+			goto error;
+	}
+
+	if (client->irq > 0) {
+		ret = devm_request_threaded_irq(&client->dev, client->irq, NULL,
+					hd3ss3220_irq_handler,
+					IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+					"hd3ss3220", &client->dev);
+		if (ret)
+			goto error;
+	}
+
+	ret = i2c_smbus_read_byte_data(client, HD3SS3220_REG_DEV_REV);
+	if (ret < 0)
+		goto error;
+
+	dev_info(&client->dev, "probed revision=0x%x\n", ret);
+
+	return 0;
+error:
+	typec_unregister_port(hd3ss3220->port);
+	usb_role_switch_put(hd3ss3220->role_sw);
+
+	return ret;
+}
+
+static int hd3ss3220_remove(struct i2c_client *client)
+{
+	struct hd3ss3220 *hd3ss3220 = i2c_get_clientdata(client);
+
+	typec_unregister_port(hd3ss3220->port);
+	usb_role_switch_put(hd3ss3220->role_sw);
+
+	return 0;
+}
+
+static const struct of_device_id dev_ids[] = {
+	{ .compatible = "ti,hd3ss3220"},
+	{}
+};
+MODULE_DEVICE_TABLE(of, dev_ids);
+
+static struct i2c_driver hd3ss3220_driver = {
+	.driver = {
+		.name = "hd3ss3220",
+		.of_match_table = of_match_ptr(dev_ids),
+	},
+	.probe = hd3ss3220_probe,
+	.remove =  hd3ss3220_remove,
+};
+
+module_i2c_driver(hd3ss3220_driver);
+
+MODULE_AUTHOR("Biju Das <biju.das@bp.renesas.com>");
+MODULE_DESCRIPTION("TI HD3SS3220 DRP Port Controller Driver");
+MODULE_LICENSE("GPL");
-- 
2.7.4

[PATCH V5 6/9] usb: gadget: udc: renesas_usb3: Use usb_role_switch framework

[Biju Das]

RZ/G2E cat874 board is capable of detecting cable connect and disconnect
events. Add support for renesas_usb3 to receive connect and disconnect
events and support dual-role switch using usb-role-switch framework.

Signed-off-by: Biju Das <biju.das@bp.renesas.com>
---
 V4-->V5
   * Incorporated Shimoda-san's review comment
    (https://patchwork.kernel.org/patch/10902537/)
 V3-->V4
   * No Change
 V2-->V3
   * Incorporated Shimoda-san's review comment
     (https://patchwork.kernel.org/patch/10852507/)
   * Used renesas,usb-role-switch property for differentiating USB
     role switch associated with Type-C port controller driver.
 V1-->V2
   * Driver uses usb role clas for handling dual role switch and handling
     connect/disconnect events instead of extcon.
---
 drivers/usb/gadget/udc/renesas_usb3.c | 92 ++++++++++++++++++++++++++++++++---
 1 file changed, 85 insertions(+), 7 deletions(-)

diff --git a/drivers/usb/gadget/udc/renesas_usb3.c b/drivers/usb/gadget/udc/renesas_usb3.c
index 7dc2485..230f5a5 100644
--- a/drivers/usb/gadget/udc/renesas_usb3.c
+++ b/drivers/usb/gadget/udc/renesas_usb3.c
@@ -351,6 +351,8 @@ struct renesas_usb3 {
 	int disabled_count;
 
 	struct usb_request *ep0_req;
+
+	enum usb_role connection_state;
 	u16 test_mode;
 	u8 ep0_buf[USB3_EP0_BUF_SIZE];
 	bool softconnect;
@@ -359,6 +361,7 @@ struct renesas_usb3 {
 	bool extcon_usb;		/* check vbus and set EXTCON_USB */
 	bool forced_b_device;
 	bool start_to_connect;
+	bool usb_role_switch_property;
 };
 
 #define gadget_to_renesas_usb3(_gadget)	\
@@ -699,8 +702,11 @@ static void usb3_mode_config(struct renesas_usb3 *usb3, bool host, bool a_dev)
 	unsigned long flags;
 
 	spin_lock_irqsave(&usb3->lock, flags);
-	usb3_set_mode_by_role_sw(usb3, host);
-	usb3_vbus_out(usb3, a_dev);
+	if (!usb3->usb_role_switch_property ||
+	    usb3->connection_state != USB_ROLE_NONE) {
+		usb3_set_mode_by_role_sw(usb3, host);
+		usb3_vbus_out(usb3, a_dev);
+	}
 	/* for A-Peripheral or forced B-device mode */
 	if ((!host && a_dev) || usb3->start_to_connect)
 		usb3_connect(usb3);
@@ -716,7 +722,9 @@ static void usb3_check_id(struct renesas_usb3 *usb3)
 {
 	usb3->extcon_host = usb3_is_a_device(usb3);
 
-	if (usb3->extcon_host && !usb3->forced_b_device)
+	if ((!usb3->usb_role_switch_property &&
+	     usb3->extcon_host && !usb3->forced_b_device) ||
+	     usb3->connection_state == USB_ROLE_HOST)
 		usb3_mode_config(usb3, true, true);
 	else
 		usb3_mode_config(usb3, false, false);
@@ -2343,14 +2351,65 @@ static enum usb_role renesas_usb3_role_switch_get(struct device *dev)
 	return cur_role;
 }
 
-static int renesas_usb3_role_switch_set(struct device *dev,
-					enum usb_role role)
+static void handle_ext_role_switch_states(struct device *dev,
+					    enum usb_role role)
+{
+	struct renesas_usb3 *usb3 = dev_get_drvdata(dev);
+	struct device *host = usb3->host_dev;
+	enum usb_role cur_role = renesas_usb3_role_switch_get(dev);
+
+	switch (role) {
+	case USB_ROLE_NONE:
+		usb3->connection_state = USB_ROLE_NONE;
+		if (usb3->driver)
+			usb3_disconnect(usb3);
+		usb3_vbus_out(usb3, false);
+		break;
+	case USB_ROLE_DEVICE:
+		if (usb3->connection_state == USB_ROLE_NONE) {
+			usb3->connection_state = USB_ROLE_DEVICE;
+			usb3_set_mode(usb3, false);
+			if (usb3->driver)
+				usb3_connect(usb3);
+		} else if (cur_role == USB_ROLE_HOST)  {
+			device_release_driver(host);
+			usb3_set_mode(usb3, false);
+			if (usb3->driver)
+				usb3_connect(usb3);
+		}
+		usb3_vbus_out(usb3, false);
+		break;
+	case USB_ROLE_HOST:
+		if (usb3->connection_state == USB_ROLE_NONE) {
+			if (usb3->driver)
+				usb3_disconnect(usb3);
+
+			usb3->connection_state = USB_ROLE_HOST;
+			usb3_set_mode(usb3, true);
+			usb3_vbus_out(usb3, true);
+			if (device_attach(host) < 0)
+				dev_err(dev, "device_attach(host) failed\n");
+		} else if (cur_role == USB_ROLE_DEVICE) {
+			usb3_disconnect(usb3);
+			/* Must set the mode before device_attach of the host */
+			usb3_set_mode(usb3, true);
+			/* This device_attach() might sleep */
+			if (device_attach(host) < 0)
+				dev_err(dev, "device_attach(host) failed\n");
+		}
+		break;
+	default:
+		break;
+	}
+}
+
+static void handle_role_switch_states(struct device *dev,
+					    enum usb_role role)
 {
 	struct renesas_usb3 *usb3 = dev_get_drvdata(dev);
 	struct device *host = usb3->host_dev;
 	enum usb_role cur_role = renesas_usb3_role_switch_get(dev);
 
-	pm_runtime_get_sync(dev);
 	if (cur_role == USB_ROLE_HOST && role == USB_ROLE_DEVICE) {
 		device_release_driver(host);
 		usb3_set_mode(usb3, false);
@@ -2361,6 +2420,20 @@ static int renesas_usb3_role_switch_set(struct device *dev,
 		if (device_attach(host) < 0)
 			dev_err(dev, "device_attach(host) failed\n");
 	}
+}
+
+static int renesas_usb3_role_switch_set(struct device *dev,
+					enum usb_role role)
+{
+	struct renesas_usb3 *usb3 = dev_get_drvdata(dev);
+
+	pm_runtime_get_sync(dev);
+
+	if (usb3->usb_role_switch_property)
+		handle_ext_role_switch_states(dev, role);
+	else
+		handle_role_switch_states(dev, role);
+
 	pm_runtime_put(dev);
 
 	return 0;
@@ -2650,7 +2723,7 @@ static const unsigned int renesas_usb3_cable[] = {
 	EXTCON_NONE,
 };
 
-static const struct usb_role_switch_desc renesas_usb3_role_switch_desc = {
+static struct usb_role_switch_desc renesas_usb3_role_switch_desc = {
 	.set = renesas_usb3_role_switch_set,
 	.get = renesas_usb3_role_switch_get,
 	.allow_userspace_control = true,
@@ -2741,6 +2814,11 @@ static int renesas_usb3_probe(struct platform_device *pdev)
 	if (ret < 0)
 		goto err_dev_create;
 
+	if (device_property_read_bool(&pdev->dev, "renesas,usb-role-switch")) {
+		usb3->usb_role_switch_property = true;
+		renesas_usb3_role_switch_desc.fwnode = dev_fwnode(&pdev->dev);
+	}
+
 	INIT_WORK(&usb3->role_work, renesas_usb3_role_work);
 	usb3->role_sw = usb_role_switch_register(&pdev->dev,
 					&renesas_usb3_role_switch_desc);
-- 
2.7.4

[PATCH V5 7/9] arm64: defconfig: enable TYPEC_HD3SS3220 config option

[Biju Das]

Enable support for the TI HD3SS320 USB Type-C DRP Port controller driver
by turning on CONFIG_TYPEC and CONFIG_TYPEC_HD3SS3220 as modules.

Signed-off-by: Biju Das <biju.das@bp.renesas.com>
---
V4-->V5
  * No change
V3-->V4
  * No change
V2-->V3
  * No change
V1-->V2
  * No change
---
 arch/arm64/configs/defconfig | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/arm64/configs/defconfig b/arch/arm64/configs/defconfig
index 04cc2a2..bc4f535 100644
--- a/arch/arm64/configs/defconfig
+++ b/arch/arm64/configs/defconfig
@@ -584,6 +584,8 @@ CONFIG_USB_ULPI=y
 CONFIG_USB_GADGET=y
 CONFIG_USB_RENESAS_USBHS_UDC=m
 CONFIG_USB_RENESAS_USB3=m
+CONFIG_TYPEC=m
+CONFIG_TYPEC_HD3SS3220=m
 CONFIG_MMC=y
 CONFIG_MMC_BLOCK_MINORS=32
 CONFIG_MMC_ARMMMCI=y
-- 
2.7.4

[PATCH V5 8/9] arm64: dts: renesas: r8a774c0-cat874: Enable USB3.0 host/peripheral device node

[Biju Das]

This patch enables USB3.0 host/peripheral device node for r8a774c0
cat874 board.

Signed-off-by: Biju Das <biju.das@bp.renesas.com>
---
V4-->V5
  * No change
V3-->V4
  * No change
V2-->V3
  * No change
V1-->V2
  * No change
---
 arch/arm64/boot/dts/renesas/r8a774c0-cat874.dts | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/arch/arm64/boot/dts/renesas/r8a774c0-cat874.dts b/arch/arm64/boot/dts/renesas/r8a774c0-cat874.dts
index 013a48c..b9ae7db 100644
--- a/arch/arm64/boot/dts/renesas/r8a774c0-cat874.dts
+++ b/arch/arm64/boot/dts/renesas/r8a774c0-cat874.dts
@@ -134,6 +134,11 @@
 		function = "sdhi0";
 		power-source = <1800>;
 	};
+
+	usb30_pins: usb30 {
+		groups = "usb30", "usb30_id";
+		function = "usb30";
+	};
 };
 
 &rwdt {
@@ -166,3 +171,15 @@
 	renesas,no-otg-pins;
 	status = "okay";
 };
+
+&usb3_peri0 {
+	companion = <&xhci0>;
+	status = "okay";
+};
+
+&xhci0 {
+	pinctrl-0 = <&usb30_pins>;
+	pinctrl-names = "default";
+
+	status = "okay";
+};
-- 
2.7.4

[PATCH V5 9/9] arm64: dts: renesas: r8a774c0-cat874: Enable usb role switch support

[Biju Das]

This patch enables TI HD3SS3220 device and support usb role switch
for the CAT 874 platform.

Signed-off-by: Biju Das <biju.das@bp.renesas.com>
---
V4-->V5
  * No change
V3-->V4
  * No change
V2-->V3
  * Used "renesas,usb-role-switch" instead of generic "usb-role-switch"
    property
V1-->V2
  * New patch
---
 arch/arm64/boot/dts/renesas/r8a774c0-cat874.dts | 39 +++++++++++++++++++++++++
 1 file changed, 39 insertions(+)

diff --git a/arch/arm64/boot/dts/renesas/r8a774c0-cat874.dts b/arch/arm64/boot/dts/renesas/r8a774c0-cat874.dts
index b9ae7db..746826c 100644
--- a/arch/arm64/boot/dts/renesas/r8a774c0-cat874.dts
+++ b/arch/arm64/boot/dts/renesas/r8a774c0-cat874.dts
@@ -85,6 +85,34 @@
 	clock-frequency = <48000000>;
 };
 
+&i2c0 {
+	status = "okay";
+	clock-frequency = <100000>;
+
+	hd3ss3220@47 {
+		compatible = "ti,hd3ss3220";
+		reg = <0x47>;
+		interrupt-parent = <&gpio6>;
+		interrupts = <3 IRQ_TYPE_LEVEL_LOW>;
+
+		usb_con: connector {
+			compatible = "usb-c-connector";
+			label = "USB-C";
+			data-role = "dual";
+		};
+
+		port {
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			hd3ss3220_ep: endpoint@0 {
+				reg = <0>;
+				remote-endpoint = <&usb3peri_role_switch>;
+			};
+		};
+	};
+};
+
 &i2c1 {
 	pinctrl-0 = <&i2c1_pins>;
 	pinctrl-names = "default";
@@ -175,6 +203,17 @@
 &usb3_peri0 {
 	companion = <&xhci0>;
 	status = "okay";
+	renesas,usb-role-switch;
+
+	port {
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		usb3peri_role_switch: endpoint@0 {
+			reg = <0>;
+			remote-endpoint = <&hd3ss3220_ep>;
+		};
+	};
 };
 
 &xhci0 {
-- 
2.7.4

Re: [PATCH V5 4/9] dt-bindings: usb: renesas_usb3: Add renesas,usb-role-switch property

[Rob Herring]

On Wed, Apr 24, 2019 at 10:22:18AM +0100, Biju Das wrote:
> Add an optional property renesas,usb-role-switch to support
> dual role switch for USB Type-C DRP port controller devices
> using USB role switch class framework.
> 
> Signed-off-by: Biju Das <biju.das@bp.renesas.com>
> ---
>  V4-->V5
>   * No Change
>  V3-->V4
>   * No Change
>  V2-->V3
>   * Added optional renesas,usb-role-switch property.
>  V1-->V2
>   * Added usb-role-switch-property
>   * Updated the example with usb-role-switch property.
> ---
>  .../devicetree/bindings/usb/renesas_usb3.txt       | 22 ++++++++++++++++++++++
>  1 file changed, 22 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/usb/renesas_usb3.txt b/Documentation/devicetree/bindings/usb/renesas_usb3.txt
> index 35039e7..f1cb06a 100644
> --- a/Documentation/devicetree/bindings/usb/renesas_usb3.txt
> +++ b/Documentation/devicetree/bindings/usb/renesas_usb3.txt
> @@ -22,6 +22,7 @@ Required properties:
>  Optional properties:
>    - phys: phandle + phy specifier pair
>    - phy-names: must be "usb"
> +  - renesas,usb-role-switch: use USB role switch to handle role switch events

Mediatek and HiSilicon both have same or similar properties in patches 
under review. Please coordinate and document a common property.

Really, I'm wondering why this is needed. Can't you walk the graph to 
the connector and determine if dual role is supported by the connector 
type?

Rob

RE: [PATCH V5 4/9] dt-bindings: usb: renesas_usb3: Add renesas,usb-role-switch property

[Biju Das]

Hi Rob,

Thanks for the feedback.

> Subject: Re: [PATCH V5 4/9] dt-bindings: usb: renesas_usb3: Add
> renesas,usb-role-switch property
> 
> On Wed, Apr 24, 2019 at 10:22:18AM +0100, Biju Das wrote:
> > Add an optional property renesas,usb-role-switch to support dual role
> > switch for USB Type-C DRP port controller devices using USB role
> > switch class framework.
> >
> > Signed-off-by: Biju Das <biju.das@bp.renesas.com>
> > ---
> >  V4-->V5
> >   * No Change
> >  V3-->V4
> >   * No Change
> >  V2-->V3
> >   * Added optional renesas,usb-role-switch property.
> >  V1-->V2
> >   * Added usb-role-switch-property
> >   * Updated the example with usb-role-switch property.
> > ---
> >  .../devicetree/bindings/usb/renesas_usb3.txt       | 22
> ++++++++++++++++++++++
> >  1 file changed, 22 insertions(+)
> >
> > diff --git a/Documentation/devicetree/bindings/usb/renesas_usb3.txt
> > b/Documentation/devicetree/bindings/usb/renesas_usb3.txt
> > index 35039e7..f1cb06a 100644
> > --- a/Documentation/devicetree/bindings/usb/renesas_usb3.txt
> > +++ b/Documentation/devicetree/bindings/usb/renesas_usb3.txt
> > @@ -22,6 +22,7 @@ Required properties:
> >  Optional properties:
> >    - phys: phandle + phy specifier pair
> >    - phy-names: must be "usb"
> > +  - renesas,usb-role-switch: use USB role switch to handle role
> > + switch events
> 
> Mediatek and HiSilicon both have same or similar properties in patches under
> review. Please coordinate and document a common property.

As per R-Car Gen3 boards design. The USB3.0 port  on the boards (Salvator-xs and Ebisu) has a USB3.0 Type-A receptor.
For debug purpose , the same port can be used as peripheral  using force_b_device mode on debugfs.
Ie, we can use force_b_device to switch the role on this boards.

Where as RZ/G2E board is having USB 3.0 type-C connector.  So the driver needs to know whether to use debugfs based
dual role switch or non-debugfs based dual role switch(type-C). That is the reason I have added this property.

> Really, I'm wondering why this is needed. Can't you walk the graph to the
> connector and determine if dual role is supported by the connector type?

Yes, Basically we don't need this property. I could walk through the graph and determine 
the role supported by connector type

Please find the example code which will be used in the driver.

+static bool is_ext_dual_role_usb_connector_available(struct device *dev)
+{
+       struct device_node *np = dev->of_node;
+       struct device_node *parent;
+       struct device_node *child;
+       bool ret = false;
+       const char *role_type = NULL;
+
+       child = of_graph_get_endpoint_by_regs(np, -1, -1);
+       if (!child)
+               return ret;
+
+       parent = of_graph_get_remote_port_parent(child);
+       of_node_put(child);
+       child = of_get_child_by_name(parent, "connector");
+       of_node_put(parent);
+       if (!child)
+               return ret;
+
+       if (of_device_is_compatible(child, "usb-c-connector")) {
+               of_property_read_string(child, "data-role", &role_type);
+               if (role_type && (!strncmp(role_type, "dual", strlen("dual"))))
+                       ret = true;
+       }
+
+       of_node_put(child);
+       return ret;
+}

Regards,
Biju

RE: [PATCH V5 4/9] dt-bindings: usb: renesas_usb3: Add renesas,usb-role-switch property

[Biju Das]

Hi Rob,


> Subject: RE: [PATCH V5 4/9] dt-bindings: usb: renesas_usb3: Add
> renesas,usb-role-switch property
> > On Wed, Apr 24, 2019 at 10:22:18AM +0100, Biju Das wrote:
> > > Add an optional property renesas,usb-role-switch to support dual
> > > role switch for USB Type-C DRP port controller devices using USB
> > > role switch class framework.
> > >
> > > Signed-off-by: Biju Das <biju.das@bp.renesas.com>
> > > ---
> > >  V4-->V5
> > >   * No Change
> > >  V3-->V4
> > >   * No Change
> > >  V2-->V3
> > >   * Added optional renesas,usb-role-switch property.
> > >  V1-->V2
> > >   * Added usb-role-switch-property
> > >   * Updated the example with usb-role-switch property.
> > > ---
> > >  .../devicetree/bindings/usb/renesas_usb3.txt       | 22
> > ++++++++++++++++++++++
> > >  1 file changed, 22 insertions(+)
> > >
> > > diff --git a/Documentation/devicetree/bindings/usb/renesas_usb3.txt
> > > b/Documentation/devicetree/bindings/usb/renesas_usb3.txt
> > > index 35039e7..f1cb06a 100644
> > > --- a/Documentation/devicetree/bindings/usb/renesas_usb3.txt
> > > +++ b/Documentation/devicetree/bindings/usb/renesas_usb3.txt
> > > @@ -22,6 +22,7 @@ Required properties:
> > >  Optional properties:
> > >    - phys: phandle + phy specifier pair
> > >    - phy-names: must be "usb"
> > > +  - renesas,usb-role-switch: use USB role switch to handle role
> > > + switch events
> >
> > Mediatek and HiSilicon both have same or similar properties in patches
> > under review. Please coordinate and document a common property.
> 
> As per R-Car Gen3 boards design. The USB3.0 port  on the boards (Salvator-xs
> and Ebisu) has a USB3.0 Type-A receptor.
> For debug purpose , the same port can be used as peripheral  using
> force_b_device mode on debugfs.
> Ie, we can use force_b_device to switch the role on this boards.
> 
> Where as RZ/G2E board is having USB 3.0 type-C connector.  So the driver
> needs to know whether to use debugfs based dual role switch or non-
> debugfs based dual role switch(type-C). That is the reason I have added this
> property.
> 
> > Really, I'm wondering why this is needed. Can't you walk the graph to
> > the connector and determine if dual role is supported by the connector
> type?
> 
> Yes, Basically we don't need this property. I could walk through the graph and
> determine the role supported by connector type
> 
> Please find the example code which will be used in the driver.
> 
> +static bool is_ext_dual_role_usb_connector_available(struct device
> +*dev) {
> +       struct device_node *np = dev->of_node;
> +       struct device_node *parent;
> +       struct device_node *child;
> +       bool ret = false;
> +       const char *role_type = NULL;
> +
> +       child = of_graph_get_endpoint_by_regs(np, -1, -1);
> +       if (!child)
> +               return ret;
> +
> +       parent = of_graph_get_remote_port_parent(child);
> +       of_node_put(child);
> +       child = of_get_child_by_name(parent, "connector");
> +       of_node_put(parent);
> +       if (!child)
> +               return ret;
> +
> +       if (of_device_is_compatible(child, "usb-c-connector")) {
> +               of_property_read_string(child, "data-role", &role_type);
> +               if (role_type && (!strncmp(role_type, "dual", strlen("dual"))))
> +                       ret = true;
> +       }
> +
> +       of_node_put(child);
> +       return ret;
> +}

Since we are introducing "usb-role-switch " common property[1],
I feel using the common-property make things simpler compared to walking through the graph. 

Are you happy with using the  common property?  Or  still prefer walk through the graph solution?
Please let me  know.

[1] https://patchwork.kernel.org/patch/10920909/

Regards,
Biju