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.

---
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
---

Fixes: 8a37d87d72f0 ("usb: typec: Bus type for alternate modes")
Cc: stable@vger.kernel.org
Signed-off-by: RD Babiera <rdbabiera@google.com>
---
 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: b85ea95d086471afb4ad062012a4d73cd328fa86
-- 
2.43.0.rc1.413.gea7ed67945-goog

On Mon, Nov 27, 2023 at 09:09:52PM +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.
> 
> ---
> 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
> ---

This info all goes below the following lines:

> 
> Fixes: 8a37d87d72f0 ("usb: typec: Bus type for alternate modes")
> Cc: stable@vger.kernel.org
> Signed-off-by: RD Babiera <rdbabiera@google.com>
> ---

Down here, otherwise if you try to apply this patch, your signed-off-by
lines are removed from the patch, right?

As-is, this can not be applied at all :(

Please fix up, thanks.

greg k-h