usb: typec: altmodes/displayport: Signal hpd low when exiting mode
authorRD Babiera <rdbabiera@google.com>
Mon, 9 Oct 2023 21:00:58 +0000 (21:00 +0000)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 19 Oct 2023 21:08:58 +0000 (23:08 +0200)
commit4d85f1ce6ca46f0af5964802ed5fa374459c6770
treed5c66817110c3ca206a88f3a41857da0d39162ce
parentbc672508592502b274e1c65038c2459654185f12
usb: typec: altmodes/displayport: Signal hpd low when exiting mode

commit 89434b069e460967624903b049e5cf5c9e6b99b9 upstream.

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@vger.kernel.org
Signed-off-by: RD Babiera <rdbabiera@google.com>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20231009210057.3773877-2-rdbabiera@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/typec/altmodes/displayport.c