This is a note to let you know that I've just added the patch titled
usb: typec: altmodes/displayport: Signal hpd low when exiting mode
to the 5.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
usb-typec-altmodes-displayport-signal-hpd-low-when-e.patch
and it can be found in the queue-5.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 5823fc58db79f5156f75ac75d6880fddebb0cab8
Author: RD Babiera <rdbabiera@xxxxxxxxxx>
Date: Mon Oct 9 21:00:58 2023 +0000
usb: typec: altmodes/displayport: Signal hpd low when exiting mode
[ Upstream commit 89434b069e460967624903b049e5cf5c9e6b99b9 ]
Upon receiving an ACK for a sent EXIT_MODE message, the DisplayPort
driver currently resets the status and configuration of the port partner.
The hpd signal is not updated despite being part of the status, so the
Display stack can still transmit video despite typec_altmode_exit placing
the lanes in a Safe State.
Set hpd to low when a sent EXIT_MODE message is ACK'ed.
Fixes: 0e3bb7d6894d ("usb: typec: Add driver for DisplayPort alternate mode")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: RD Babiera <rdbabiera@xxxxxxxxxx>
Acked-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20231009210057.3773877-2-rdbabiera@xxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/usb/typec/altmodes/displayport.c b/drivers/usb/typec/altmodes/displayport.c
index 8083d5faf0c98..def903e9d2ab4 100644
--- a/drivers/usb/typec/altmodes/displayport.c
+++ b/drivers/usb/typec/altmodes/displayport.c
@@ -285,6 +285,11 @@ static int dp_altmode_vdm(struct typec_altmode *alt,
case CMD_EXIT_MODE:
dp->data.status = 0;
dp->data.conf = 0;
+ if (dp->hpd) {
+ drm_connector_oob_hotplug_event(dp->connector_fwnode);
+ dp->hpd = false;
+ sysfs_notify(&dp->alt->dev.kobj, "displayport", "hpd");
+ }
break;
case DP_CMD_STATUS_UPDATE:
dp->data.status = *vdo;
