patch "usb: typec: class: fix typec_altmode_put_partner to put plugs" added to usb-next

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    usb: typec: class: fix typec_altmode_put_partner to put plugs

to my usb git tree which can be found at
    git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git
in the usb-next branch.

The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)

The patch will also be merged in the next major kernel release
during the merge window.

If you have any questions about this process, please let me know.


From 5962ded777d689cd8bf04454273e32228d7fb71f Mon Sep 17 00:00:00 2001
From: RD Babiera <rdbabiera@google.com>
Date: Wed, 3 Jan 2024 18:17:55 +0000
Subject: usb: typec: class: fix typec_altmode_put_partner to put plugs

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 is a plug evaluates
against the released altmode's partner instead of the calling altmode, so
change adev in typec_altmode_put_partner to properly refer to the altmode
being released.

Because typec_altmode_set_partner calls get_device() on the port altmode,
add partner_adev that points to the port altmode in typec_put_partner to
call put_device() on. typec_altmode_set_partner is not called for port
altmodes, so 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>
Co-developed-by: Christian A. Ehrhardt <lk@c--e.de>
Signed-off-by: Christian A. Ehrhardt <lk@c--e.de>
Signed-off-by: RD Babiera <rdbabiera@google.com>
Tested-by: Christian A. Ehrhardt <lk@c--e.de>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20240103181754.2492492-2-rdbabiera@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/usb/typec/class.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/usb/typec/class.c b/drivers/usb/typec/class.c
index 4d11f2b536fa..015aa9253353 100644
--- a/drivers/usb/typec/class.c
+++ b/drivers/usb/typec/class.c
@@ -263,11 +263,13 @@ static void typec_altmode_put_partner(struct altmode *altmode)
 {
 	struct altmode *partner = altmode->partner;
 	struct typec_altmode *adev;
+	struct typec_altmode *partner_adev;
 
 	if (!partner)
 		return;
 
-	adev = &partner->adev;
+	adev = &altmode->adev;
+	partner_adev = &partner->adev;
 
 	if (is_typec_plug(adev->dev.parent)) {
 		struct typec_plug *plug = to_typec_plug(adev->dev.parent);
@@ -276,7 +278,7 @@ static void typec_altmode_put_partner(struct altmode *altmode)
 	} else {
 		partner->partner = NULL;
 	}
-	put_device(&adev->dev);
+	put_device(&partner_adev->dev);
 }
 
 /**
@@ -497,7 +499,8 @@ 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);
-- 
2.43.0