[PATCH v2 0/4] Add ext. port vbus handling for onboard-dev

[PATCH v2 0/4] Add ext. port vbus handling for onboard-dev

[Marco Felsch]

Hi,

this small series is the successor of [1]. The intend of this series is
to make it possible to switch the vbus of the downstream ports of an
onboard-dev hub via ext. regulators controlled via the host.

The approach from v1 was not sufficient since it caused compile errors.
We indentified the issue and went with idea-3 [2] to fix this.

Regards,
  Marco

[1] https://lore.kernel.org/all/20240807-b4-v6-10-topic-usb-onboard-dev-v1-0-f33ce21353c9@pengutronix.de/
[2] https://lore.kernel.org/all/wtvhsdo2zefehkgfcp2cfdl2uht4lcrytyjyhwjhnpcyvx4kd2@iurrw554aegh/

Marco Felsch (4):
  usb: port: track the disabled state
  usb: hub: add infrastructure to pass onboard_dev port features
  dt-bindings: usb: microchip,usb2514: add support for port vbus-supply
  usb: misc: onboard_dev: add ext-vbus-supply handling

 .../bindings/usb/microchip,usb2514.yaml       |  6 ++
 drivers/usb/core/hub.c                        | 55 ++++++++++-
 drivers/usb/core/hub.h                        |  4 +
 drivers/usb/core/port.c                       |  6 ++
 drivers/usb/misc/onboard_usb_dev.c            | 95 +++++++++++++++++++
 drivers/usb/misc/onboard_usb_dev.h            |  3 +
 include/linux/usb.h                           |  3 +
 7 files changed, 170 insertions(+), 2 deletions(-)

-- 
2.39.5

[PATCH v2 1/4] usb: port: track the disabled state

[Marco Felsch]

The disable state isn't tracked at the moment, instead the state is
directly passed to the hub driver. Change this behavior to only trigger
the hub if a state change happened. Exit early in case of no state
changes but don't return an error.

Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
---
 drivers/usb/core/hub.h  | 2 ++
 drivers/usb/core/port.c | 6 ++++++
 2 files changed, 8 insertions(+)

diff --git a/drivers/usb/core/hub.h b/drivers/usb/core/hub.h
index e6ae73f8a95d..9e91add60b1c 100644
--- a/drivers/usb/core/hub.h
+++ b/drivers/usb/core/hub.h
@@ -96,6 +96,7 @@ struct usb_hub {
  * @usb3_lpm_u2_permit: whether USB3 U2 LPM is permitted.
  * @early_stop: whether port initialization will be stopped earlier.
  * @ignore_event: whether events of the port are ignored.
+ * @disabled: whether the port is disabled
  */
 struct usb_port {
 	struct usb_device *child;
@@ -117,6 +118,7 @@ struct usb_port {
 	unsigned int is_superspeed:1;
 	unsigned int usb3_lpm_u1_permit:1;
 	unsigned int usb3_lpm_u2_permit:1;
+	unsigned int disabled:1;
 };
 
 #define to_usb_port(_dev) \
diff --git a/drivers/usb/core/port.c b/drivers/usb/core/port.c
index f54198171b6a..cae08a9a71e6 100644
--- a/drivers/usb/core/port.c
+++ b/drivers/usb/core/port.c
@@ -117,6 +117,10 @@ static ssize_t disable_store(struct device *dev, struct device_attribute *attr,
 	if (rc)
 		return rc;
 
+	/* Early quit if no change was detected */
+	if (port_dev->disabled == disabled)
+		return count;
+
 	hub_get(hub);
 	rc = usb_autopm_get_interface(intf);
 	if (rc < 0)
@@ -148,6 +152,8 @@ static ssize_t disable_store(struct device *dev, struct device_attribute *attr,
 			usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_ENABLE);
 	}
 
+	port_dev->disabled = disabled;
+
 	if (!rc)
 		rc = count;
 
-- 
2.39.5

[PATCH v2 2/4] usb: hub: add infrastructure to pass onboard_dev port features

[Marco Felsch]

On board devices may require special handling for en-/disable port
features due to PCB design decisions e.g. enable/disable the VBUS power
on the port via a host controlled regulator or GPIO.

This commit adds the necessary infrastructure to prepare the common code
base for such use-cases.

Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
---
 drivers/usb/core/hub.c | 55 ++++++++++++++++++++++++++++++++++++++++--
 drivers/usb/core/hub.h |  2 ++
 include/linux/usb.h    |  3 +++
 3 files changed, 58 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index c3f839637cb5..a1b6040bb2e4 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -451,9 +451,19 @@ static int clear_hub_feature(struct usb_device *hdev, int feature)
  */
 int usb_clear_port_feature(struct usb_device *hdev, int port1, int feature)
 {
-	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
+	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
+	int ret;
+
+	ret = usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 		USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
 		NULL, 0, 1000);
+	if (ret)
+		return ret;
+
+	if (hub->onboard_hub_clear_port_feature)
+		ret = hub->onboard_hub_clear_port_feature(hdev, feature, port1);
+
+	return ret;
 }
 
 /*
@@ -461,9 +471,19 @@ int usb_clear_port_feature(struct usb_device *hdev, int port1, int feature)
  */
 static int set_port_feature(struct usb_device *hdev, int port1, int feature)
 {
-	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
+	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
+	int ret;
+
+	ret = usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 		USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
 		NULL, 0, 1000);
+	if (ret)
+		return ret;
+
+	if (hub->onboard_hub_set_port_feature)
+		ret = hub->onboard_hub_set_port_feature(hdev, feature, port1);
+
+	return ret;
 }
 
 static char *to_led_name(int selector)
@@ -6452,6 +6472,37 @@ void usb_hub_adjust_deviceremovable(struct usb_device *hdev,
 	}
 }
 
+/**
+ * usb_hub_register_port_feature_hooks - Register port set/get feature hooks
+ * @hdev: USB device belonging to the usb hub
+ * @set_port_feature: set_feature hook which gets called by the hub core
+ * @clear_port_feature: clear_feature hook which gets called by the hub core
+ *
+ * Register set/get_port_feature hooks for a onboard_dev hub.
+ */
+void usb_hub_register_port_feature_hooks(struct usb_device *hdev,
+		int (*set_port_feature)(struct usb_device *, int, int),
+		int (*clear_port_feature)(struct usb_device *, int, int))
+{
+	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
+
+	if (WARN_ON_ONCE(is_root_hub(hdev) || !hub))
+		return;
+
+	if (set_port_feature)
+		hub->onboard_hub_set_port_feature = set_port_feature;
+	if (clear_port_feature)
+		hub->onboard_hub_clear_port_feature = clear_port_feature;
+
+	/*
+	 * Keep it simple for now. Just check the power state and re-sync it
+	 * after adding the hooks since the onboard-dev may do some additional
+	 * logic e.g. controlling regulators.
+	 */
+	hub_power_on(hub, false);
+}
+EXPORT_SYMBOL_GPL(usb_hub_register_port_feature_hooks);
+
 #ifdef CONFIG_ACPI
 /**
  * usb_get_hub_port_acpi_handle - Get the usb port's acpi handle
diff --git a/drivers/usb/core/hub.h b/drivers/usb/core/hub.h
index 9e91add60b1c..536894092db4 100644
--- a/drivers/usb/core/hub.h
+++ b/drivers/usb/core/hub.h
@@ -75,6 +75,8 @@ struct usb_hub {
 	struct timer_list	irq_urb_retry;
 	struct usb_port		**ports;
 	struct list_head        onboard_devs;
+	int (*onboard_hub_set_port_feature)(struct usb_device *udev, int feature, int port1);
+	int (*onboard_hub_clear_port_feature)(struct usb_device *udev, int feature, int port1);
 };
 
 /**
diff --git a/include/linux/usb.h b/include/linux/usb.h
index cfa8005e24f9..bec98f2b7735 100644
--- a/include/linux/usb.h
+++ b/include/linux/usb.h
@@ -924,6 +924,9 @@ int usb_hub_claim_port(struct usb_device *hdev, unsigned port1,
 		struct usb_dev_state *owner);
 int usb_hub_release_port(struct usb_device *hdev, unsigned port1,
 		struct usb_dev_state *owner);
+void usb_hub_register_port_feature_hooks(struct usb_device *hdev,
+		int (*set_port_feature)(struct usb_device *, int, int),
+		int (*clear_port_feature)(struct usb_device *, int, int));
 
 /**
  * usb_make_path - returns stable device path in the usb tree
-- 
2.39.5

[PATCH v2 3/4] dt-bindings: usb: microchip,usb2514: add support for port vbus-supply

[Marco Felsch]

Some PCB designs don't connect the USB hub port power control GPIO and
instead make use of a host controllable regulator. Add support for this
use-case by introducing portX-vbus-supply property.

Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
---
 .../devicetree/bindings/usb/microchip,usb2514.yaml          | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/Documentation/devicetree/bindings/usb/microchip,usb2514.yaml b/Documentation/devicetree/bindings/usb/microchip,usb2514.yaml
index 4e3901efed3f..ae6a9fb4f3d0 100644
--- a/Documentation/devicetree/bindings/usb/microchip,usb2514.yaml
+++ b/Documentation/devicetree/bindings/usb/microchip,usb2514.yaml
@@ -49,6 +49,12 @@ patternProperties:
     $ref: /schemas/usb/usb-device.yaml
     additionalProperties: true
 
+  "^port[1-7]-vbus-supply$"
+    type: object
+    description:
+      Regulator controlling the USB VBUS on portX. Only required if the host
+      controls the portX VBUS.
+
 allOf:
   - $ref: usb-device.yaml#
   - if:
-- 
2.39.5

[PATCH v2 4/4] usb: misc: onboard_dev: add ext-vbus-supply handling

[Marco Felsch]

Add support to power the port VBUS via host controlled regulators since
some embedded hub PCB designs don't connect the dedicated USB hub port
power GPIOs accordingly.

To support the above use-case this commits adds support to parse the OF
information and setup the regulators accordingly within the platform
driver part. Furthermore the usb driver registers the set/clear features
hooks via the new usb_hub_register_port_feature_hooks() if the
onboard_dev is a hub. Afterwards all generic hub handling is passed to
the onboard_dev driver too which allows us to control the regulators.

At the moment this feature is limited to the following hubs:
  - usb424,2412
  - usb424,2414
  - usb424,2417

Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
---
 drivers/usb/misc/onboard_usb_dev.c | 95 ++++++++++++++++++++++++++++++
 drivers/usb/misc/onboard_usb_dev.h |  3 +
 2 files changed, 98 insertions(+)

diff --git a/drivers/usb/misc/onboard_usb_dev.c b/drivers/usb/misc/onboard_usb_dev.c
index 75ac3c6aa92d..7ec47509937c 100644
--- a/drivers/usb/misc/onboard_usb_dev.c
+++ b/drivers/usb/misc/onboard_usb_dev.c
@@ -48,6 +48,8 @@ static DECLARE_WORK(attach_usb_driver_work, onboard_dev_attach_usb_driver);
 
 /************************** Platform driver **************************/
 
+#define MAX_DOWNSTREAM_PORTS	7
+
 struct usbdev_node {
 	struct usb_device *udev;
 	struct list_head list;
@@ -64,6 +66,7 @@ struct onboard_dev {
 	struct list_head udev_list;
 	struct mutex lock;
 	struct clk *clk;
+	struct regulator *ext_vbus_supplies[MAX_DOWNSTREAM_PORTS];
 };
 
 static int onboard_dev_get_regulators(struct onboard_dev *onboard_dev)
@@ -225,6 +228,53 @@ static int onboard_dev_add_usbdev(struct onboard_dev *onboard_dev,
 	return err;
 }
 
+static int onboard_dev_port_power(struct onboard_dev *onboard_dev, int port1,
+				  bool enable)
+{
+	struct regulator *vbus_supply;
+	unsigned int port = port1 - 1;
+
+	if (WARN_ON(port >= MAX_DOWNSTREAM_PORTS))
+		return -EINVAL;
+
+	vbus_supply = onboard_dev->ext_vbus_supplies[port];
+
+	/* External supplies are optional */
+	if (!vbus_supply)
+		return 0;
+
+	if (enable)
+		return regulator_enable(vbus_supply);
+
+	return regulator_disable(vbus_supply);
+}
+
+static int onboard_dev_add_ext_vbus_supplies(struct onboard_dev *onboard_dev)
+{
+	struct device *dev = onboard_dev->dev;
+	unsigned int i;
+
+	if (!onboard_dev->pdata->support_ext_vbus_supplies)
+		return 0;
+
+	for (i = 0; i < MAX_DOWNSTREAM_PORTS; i++) {
+		char supply_name[] = "portX-vbus";
+		struct regulator *reg;
+
+		sprintf(supply_name, "port%u-vbus", i + 1);
+		reg = devm_regulator_get_optional(dev, supply_name);
+		if (!IS_ERR(reg)) {
+			onboard_dev->ext_vbus_supplies[i] = reg;
+		} else {
+			if (PTR_ERR(reg) != -ENODEV)
+				return dev_err_probe(dev, PTR_ERR(reg),
+						     "failed to get %s-supply\n", supply_name);
+		}
+	}
+
+	return 0;
+}
+
 static void onboard_dev_remove_usbdev(struct onboard_dev *onboard_dev,
 				      const struct usb_device *udev)
 {
@@ -383,6 +433,10 @@ static int onboard_dev_probe(struct platform_device *pdev)
 		return dev_err_probe(dev, PTR_ERR(onboard_dev->reset_gpio),
 				     "failed to get reset GPIO\n");
 
+	err = onboard_dev_add_ext_vbus_supplies(onboard_dev);
+	if (err)
+		return err;
+
 	mutex_init(&onboard_dev->lock);
 	INIT_LIST_HEAD(&onboard_dev->udev_list);
 
@@ -495,6 +549,44 @@ static struct platform_driver onboard_dev_driver = {
 #define VENDOR_ID_VIA		0x2109
 #define VENDOR_ID_XMOS		0x20B1
 
+static int onboard_dev_port_feature(struct usb_device *udev, bool set,
+				    int feature, int port1)
+{
+	struct device *dev = &udev->dev;
+	struct onboard_dev *onboard_dev = dev_get_drvdata(dev);
+
+	/*
+	 * Check usb_hub_register_port_feature_hooks() if you want to extent
+	 * the list of handled features. At the moment only power is synced
+	 * after adding the hook.
+	 */
+	switch (feature) {
+	case USB_PORT_FEAT_POWER:
+		return onboard_dev_port_power(onboard_dev, port1, set);
+	default:
+		return 0;
+	}
+}
+
+static int
+onboard_dev_set_port_feature(struct usb_device *udev, int feature, int port1)
+{
+	return onboard_dev_port_feature(udev, true, feature, port1);
+}
+
+static int
+onboard_dev_clear_port_feature(struct usb_device *udev, int feature, int port1)
+{
+	return onboard_dev_port_feature(udev, false, feature, port1);
+}
+
+static void
+onboard_dev_register_hub_hooks(struct usb_device *udev)
+{
+	usb_hub_register_port_feature_hooks(udev, onboard_dev_set_port_feature,
+					    onboard_dev_clear_port_feature);
+}
+
 /*
  * Returns the onboard_dev platform device that is associated with the USB
  * device passed as parameter.
@@ -554,6 +646,9 @@ static int onboard_dev_usbdev_probe(struct usb_device *udev)
 
 	dev_set_drvdata(dev, onboard_dev);
 
+	if (onboard_dev->pdata->is_hub)
+		onboard_dev_register_hub_hooks(udev);
+
 	err = onboard_dev_add_usbdev(onboard_dev, udev);
 	if (err)
 		return err;
diff --git a/drivers/usb/misc/onboard_usb_dev.h b/drivers/usb/misc/onboard_usb_dev.h
index 933797a7e084..d15e501f5fc9 100644
--- a/drivers/usb/misc/onboard_usb_dev.h
+++ b/drivers/usb/misc/onboard_usb_dev.h
@@ -14,6 +14,7 @@ struct onboard_dev_pdata {
 	unsigned int num_supplies;	/* number of supplies */
 	const char * const supply_names[MAX_SUPPLIES];
 	bool is_hub;
+	bool support_ext_vbus_supplies;
 };
 
 static const struct onboard_dev_pdata microchip_usb424_data = {
@@ -21,6 +22,7 @@ static const struct onboard_dev_pdata microchip_usb424_data = {
 	.num_supplies = 1,
 	.supply_names = { "vdd" },
 	.is_hub = true,
+	.support_ext_vbus_supplies = true,
 };
 
 static const struct onboard_dev_pdata microchip_usb2514_data = {
@@ -28,6 +30,7 @@ static const struct onboard_dev_pdata microchip_usb2514_data = {
 	.num_supplies = 2,
 	.supply_names = { "vdd", "vdda" },
 	.is_hub = true,
+	.support_ext_vbus_supplies = true,
 };
 
 static const struct onboard_dev_pdata microchip_usb5744_data = {
-- 
2.39.5

Re: [PATCH v2 3/4] dt-bindings: usb: microchip,usb2514: add support for port vbus-supply

[Rob Herring (Arm)]

On Thu, 27 Mar 2025 18:28:02 +0100, Marco Felsch wrote:
> Some PCB designs don't connect the USB hub port power control GPIO and
> instead make use of a host controllable regulator. Add support for this
> use-case by introducing portX-vbus-supply property.
> 
> Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
> ---
>  .../devicetree/bindings/usb/microchip,usb2514.yaml          | 6 ++++++
>  1 file changed, 6 insertions(+)
> 

My bot found errors running 'make dt_binding_check' on your patch:

yamllint warnings/errors:
./Documentation/devicetree/bindings/usb/microchip,usb2514.yaml:53:5: [error] syntax error: could not find expected ':' (syntax)

dtschema/dtc warnings/errors:
/builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/usb/microchip,usb2514.yaml: ignoring, error parsing file
./Documentation/devicetree/bindings/usb/microchip,usb2514.yaml:53:5: could not find expected ':'
make[2]: *** Deleting file 'Documentation/devicetree/bindings/usb/microchip,usb2514.example.dts'
Documentation/devicetree/bindings/usb/microchip,usb2514.yaml:53:5: could not find expected ':'
make[2]: *** [Documentation/devicetree/bindings/Makefile:26: Documentation/devicetree/bindings/usb/microchip,usb2514.example.dts] Error 1
make[2]: *** Waiting for unfinished jobs....
make[1]: *** [/builds/robherring/dt-review-ci/linux/Makefile:1522: dt_binding_check] Error 2
make: *** [Makefile:248: __sub-make] Error 2

doc reference errors (make refcheckdocs):

See https://patchwork.ozlabs.org/project/devicetree-bindings/patch/20250327172803.3404615-4-m.felsch@pengutronix.de

The base for the series is generally the latest rc1. A different dependency
should be noted in *this* patch.

If you already ran 'make dt_binding_check' and didn't see the above
error(s), then make sure 'yamllint' is installed and dt-schema is up to
date:

pip3 install dtschema --upgrade

Please check and re-submit after running the above command yourself. Note
that DT_SCHEMA_FILES can be set to your schema file to speed up checking
your schema. However, it must be unset to test all examples with your schema.