On Mon, Oct 09, 2023 at 09:00:58PM +0000, RD Babiera wrote:
> 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>
> ---
> drivers/usb/typec/altmodes/displayport.c | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/drivers/usb/typec/altmodes/displayport.c b/drivers/usb/typec/altmodes/displayport.c
> index f503cb4cd721..718da02036d8 100644
> --- a/drivers/usb/typec/altmodes/displayport.c
> +++ b/drivers/usb/typec/altmodes/displayport.c
> @@ -307,6 +307,11 @@ static int dp_altmode_vdm(struct typec_altmode *alt,
> typec_altmode_update_active(alt, false);
> 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;
>
> base-commit: 1053c4a4b8fcbd28386e80347e7c82d4d617e352
> --
> 2.42.0.609.gbb76f46606-goog
--
heikki
