This new field in the port properties dictates whether the Platform Policy
Manager (PPM) allows the OS Policy Manager (OPM) to change the currently
active, negotiated alternate mode.

Signed-off-by: Andrei Kuchynski <akuchynski@chromium.org>
---
 drivers/usb/typec/class.c | 9 ++++++---
 drivers/usb/typec/class.h | 2 ++
 include/linux/usb/typec.h | 2 ++
 3 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/drivers/usb/typec/class.c b/drivers/usb/typec/class.c
index 67a533e35150..9f86605ce125 100644
--- a/drivers/usb/typec/class.c
+++ b/drivers/usb/typec/class.c
@@ -457,11 +457,13 @@ static umode_t typec_altmode_attr_is_visible(struct kobject *kobj,
 					     struct attribute *attr, int n)
 {
 	struct typec_altmode *adev = to_typec_altmode(kobj_to_dev(kobj));
+	struct typec_port *port = typec_altmode2port(adev);
 
 	if (attr == &dev_attr_active.attr)
-		if (!is_typec_port(adev->dev.parent) &&
-		    (!adev->ops || !adev->ops->activate))
-			return 0444;
+		if (!is_typec_port(adev->dev.parent)) {
+			if (!port->mode_control || !adev->ops || !adev->ops->activate)
+				return 0444;
+		}
 
 	return attr->mode;
 }
@@ -2681,6 +2683,7 @@ struct typec_port *typec_register_port(struct device *parent,
 	}
 
 	port->pd = cap->pd;
+	port->mode_control = !cap->no_mode_control;
 
 	ret = device_add(&port->dev);
 	if (ret) {
diff --git a/drivers/usb/typec/class.h b/drivers/usb/typec/class.h
index db2fe96c48ff..c53a04b9dc75 100644
--- a/drivers/usb/typec/class.h
+++ b/drivers/usb/typec/class.h
@@ -80,6 +80,8 @@ struct typec_port {
 	 */
 	struct device			*usb2_dev;
 	struct device			*usb3_dev;
+
+	bool				mode_control;
 };
 
 #define to_typec_port(_dev_) container_of(_dev_, struct typec_port, dev)
diff --git a/include/linux/usb/typec.h b/include/linux/usb/typec.h
index 252af3f77039..8f51665d44ec 100644
--- a/include/linux/usb/typec.h
+++ b/include/linux/usb/typec.h
@@ -287,6 +287,7 @@ enum usb_pd_svdm_ver {
  * @prefer_role: Initial role preference (DRP ports).
  * @accessory: Supported Accessory Modes
  * @usb_capability: Supported USB Modes
+ * @no_mode_control: Ability to manage Alternate Modes
  * @fwnode: Optional fwnode of the port
  * @driver_data: Private pointer for driver specific info
  * @pd: Optional USB Power Delivery Support
@@ -304,6 +305,7 @@ struct typec_capability {
 	enum typec_accessory	accessory[TYPEC_MAX_ACCESSORY];
 	unsigned int		orientation_aware:1;
 	u8			usb_capability;
+	bool			no_mode_control;
 
 	struct fwnode_handle	*fwnode;
 	void			*driver_data;
-- 
2.51.0.355.g5224444f11-goog

On Fri, Sep 05, 2025 at 02:22:02PM +0000, Andrei Kuchynski wrote:
> This new field in the port properties dictates whether the Platform Policy
> Manager (PPM) allows the OS Policy Manager (OPM) to change the currently
> active, negotiated alternate mode.
> 
> Signed-off-by: Andrei Kuchynski <akuchynski@chromium.org>

Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>

> ---
>  drivers/usb/typec/class.c | 9 ++++++---
>  drivers/usb/typec/class.h | 2 ++
>  include/linux/usb/typec.h | 2 ++
>  3 files changed, 10 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/usb/typec/class.c b/drivers/usb/typec/class.c
> index 67a533e35150..9f86605ce125 100644
> --- a/drivers/usb/typec/class.c
> +++ b/drivers/usb/typec/class.c
> @@ -457,11 +457,13 @@ static umode_t typec_altmode_attr_is_visible(struct kobject *kobj,
>  					     struct attribute *attr, int n)
>  {
>  	struct typec_altmode *adev = to_typec_altmode(kobj_to_dev(kobj));
> +	struct typec_port *port = typec_altmode2port(adev);
>  
>  	if (attr == &dev_attr_active.attr)
> -		if (!is_typec_port(adev->dev.parent) &&
> -		    (!adev->ops || !adev->ops->activate))
> -			return 0444;
> +		if (!is_typec_port(adev->dev.parent)) {
> +			if (!port->mode_control || !adev->ops || !adev->ops->activate)
> +				return 0444;
> +		}
>  
>  	return attr->mode;
>  }
> @@ -2681,6 +2683,7 @@ struct typec_port *typec_register_port(struct device *parent,
>  	}
>  
>  	port->pd = cap->pd;
> +	port->mode_control = !cap->no_mode_control;
>  
>  	ret = device_add(&port->dev);
>  	if (ret) {
> diff --git a/drivers/usb/typec/class.h b/drivers/usb/typec/class.h
> index db2fe96c48ff..c53a04b9dc75 100644
> --- a/drivers/usb/typec/class.h
> +++ b/drivers/usb/typec/class.h
> @@ -80,6 +80,8 @@ struct typec_port {
>  	 */
>  	struct device			*usb2_dev;
>  	struct device			*usb3_dev;
> +
> +	bool				mode_control;
>  };
>  
>  #define to_typec_port(_dev_) container_of(_dev_, struct typec_port, dev)
> diff --git a/include/linux/usb/typec.h b/include/linux/usb/typec.h
> index 252af3f77039..8f51665d44ec 100644
> --- a/include/linux/usb/typec.h
> +++ b/include/linux/usb/typec.h
> @@ -287,6 +287,7 @@ enum usb_pd_svdm_ver {
>   * @prefer_role: Initial role preference (DRP ports).
>   * @accessory: Supported Accessory Modes
>   * @usb_capability: Supported USB Modes
> + * @no_mode_control: Ability to manage Alternate Modes
>   * @fwnode: Optional fwnode of the port
>   * @driver_data: Private pointer for driver specific info
>   * @pd: Optional USB Power Delivery Support
> @@ -304,6 +305,7 @@ struct typec_capability {
>  	enum typec_accessory	accessory[TYPEC_MAX_ACCESSORY];
>  	unsigned int		orientation_aware:1;
>  	u8			usb_capability;
> +	bool			no_mode_control;
>  
>  	struct fwnode_handle	*fwnode;
>  	void			*driver_data;
> -- 
> 2.51.0.355.g5224444f11-goog

-- 
heikki