[PATCH] drm/bridge: analogix_dp: Make PSR-disable non-blocking

[Brian Norris]

Prior to commit 6c836d965bad ("drm/rockchip: Use the helpers for PSR"),
"PSR disable" used non-blocking analogix_dp_send_psr_spd(). The refactor
accidentally (?) set blocking=true.

This can cause upwards of 60-100ms of unneeded latency when exiting
self-refresh, which can cause very noticeable lag when, say, moving a
cursor.

Presumbaly it's OK to let the display finish exiting refresh in parallel
with clocking out the next video frames, so we shouldn't hold up the
atomic_enable() step. This also brings behavior in line with the
downstream ("mainline-derived") variant of the driver currently deployed
to Chrome OS Rockchip systems.

Tested on a Samsung Chromebook Plus (i.e., Rockchip RK3399 Gru Kevin).

Fixes: 6c836d965bad ("drm/rockchip: Use the helpers for PSR")
Cc: <stable at vger.kernel.org>
Cc: Zain Wang <wzz at rock-chips.com>
Cc: Tomasz Figa <tfiga at chromium.org>
Cc: Heiko Stuebner <heiko at sntech.de>
Cc: Sean Paul <seanpaul at chromium.org>
Signed-off-by: Brian Norris <briannorris at chromium.org>
---
CC list is partially constructed from the commit message of the Fixed
commit

 drivers/gpu/drm/bridge/analogix/analogix_dp_core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
index b7d2e4449cfa..fbe6eb9df310 100644
--- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
+++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
@@ -1055,7 +1055,7 @@ static int analogix_dp_disable_psr(struct analogix_dp_device *dp)
 	psr_vsc.db[0] = 0;
 	psr_vsc.db[1] = 0;
 
-	return analogix_dp_send_psr_spd(dp, &psr_vsc, true);
+	return analogix_dp_send_psr_spd(dp, &psr_vsc, false);
 }
 
 /*
-- 
2.33.0.1079.g6e70778dc9-goog