Re: [PATCH v3] usb: typec: class: fix typec_altmode_put_partner to put plugs

[Heikki Krogerus <heikki.krogerus@linux.intel.com>]

On Wed, Nov 29, 2023 at 07:23:50PM +0000, RD Babiera wrote:
> When typec_altmode_put_partner is called by a plug altmode upon release,
> the port altmode the plug belongs to will not remove its reference to the
> plug. The check to see if the altmode being released evaluates against the
> released altmode's partner instead of the calling altmode itself, so change
> adev in typec_altmode_put_partner to properly refer to the altmode being
> released.
> 
> typec_altmode_set_partner is not run for port altmodes, so also add a check
> in typec_altmode_release to prevent typec_altmode_put_partner() calls on
> port altmode release.
> 
> Fixes: 8a37d87d72f0 ("usb: typec: Bus type for alternate modes")
> Cc: stable@vger.kernel.org
> Signed-off-by: RD Babiera <rdbabiera@google.com>

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

> ---
> Changes since v2:
> * Moved changelog under "Signed-off-by" tag
> 
> Changes since v1:
> * Changed commit message for clarity
> * Added check to typec_altmode_release to only call put_partner if altmode
> belongs to port partner or plug
> ---
>  drivers/usb/typec/class.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/usb/typec/class.c b/drivers/usb/typec/class.c
> index 2e0451bd336e..16a670828dde 100644
> --- a/drivers/usb/typec/class.c
> +++ b/drivers/usb/typec/class.c
> @@ -267,7 +267,7 @@ static void typec_altmode_put_partner(struct altmode *altmode)
>  	if (!partner)
>  		return;
>  
> -	adev = &partner->adev;
> +	adev = &altmode->adev;
>  
>  	if (is_typec_plug(adev->dev.parent)) {
>  		struct typec_plug *plug = to_typec_plug(adev->dev.parent);
> @@ -497,7 +497,8 @@ static void typec_altmode_release(struct device *dev)
>  {
>  	struct altmode *alt = to_altmode(to_typec_altmode(dev));
>  
> -	typec_altmode_put_partner(alt);
> +	if (!is_typec_port(dev->parent))
> +		typec_altmode_put_partner(alt);
>  
>  	altmode_id_remove(alt->adev.dev.parent, alt->id);
>  	kfree(alt);
> 
> base-commit: 24af68a0ed53629bdde7b53ef8c2be72580d293b
> -- 
> 2.43.0.rc1.413.gea7ed67945-goog

-- 
heikki