Re: [PATCH v3 1/5] usb: typec: Add mode_control field to port property

From: Heikki Krogerus

Date: Tue Sep 09 2025 - 04:47:48 EST


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@xxxxxxxxxxxx>

Reviewed-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>

> ---
> 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