4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sean Paul <seanpaul@xxxxxxxxxxxx> [ Upstream commit 5f3417569165a8ee57654217f73e0160312f409c ] The bridge loses its hw state when the cable is unplugged. If we detect this case in the hpd handler, reset its state. Reported-by: Rob Clark <robdclark@xxxxxxxxx> Tested-by: Rob Clark <robdclark@xxxxxxxxx> Reviewed-by: Archit Taneja <architt@xxxxxxxxxxxxxx> Signed-off-by: Sean Paul <seanpaul@xxxxxxxxxxxx> Link: https://patchwork.freedesktop.org/patch/msgid/20180703165648.120401-1-seanpaul@xxxxxxxxxxxx Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) --- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c +++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c @@ -424,6 +424,18 @@ static void adv7511_hpd_work(struct work else status = connector_status_disconnected; + /* + * The bridge resets its registers on unplug. So when we get a plug + * event and we're already supposed to be powered, cycle the bridge to + * restore its state. + */ + if (status == connector_status_connected && + adv7511->connector.status == connector_status_disconnected && + adv7511->powered) { + regcache_mark_dirty(adv7511->regmap); + adv7511_power_on(adv7511); + } + if (adv7511->connector.status != status) { adv7511->connector.status = status; drm_kms_helper_hotplug_event(adv7511->connector.dev);
