From 7ea66d702e07eea323922891abadd8e646f4085d Mon Sep 17 00:00:00 2001
From: AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org>
Date: Sat, 11 Sep 2021 18:39:19 +0200
Subject: drm/msm/dpu: Fix timeout issues on command mode panels
Git-commit: 050770cbbd26d1cc2d5f4718a4595e19cb3403d8
Patch-mainline: v5.18-rc1
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225

In function dpu_encoder_phys_cmd_wait_for_commit_done we are always
checking if the relative CTL is started by waiting for an interrupt
to fire: it is fine to do that, but then sometimes we call this
function while the CTL is up and has never been put down, but that
interrupt gets raised only when the CTL gets a state change from
0 to 1 (disabled to enabled), so we're going to wait for something
that will never happen on its own.

Solving this while avoiding to restart the CTL is actually possible
and can be done by just checking if it is already up and running
when the wait_for_commit_done function is called: in this case, so,
if the CTL was already running, we can say that the commit is done
if the command transmission is complete (in other terms, if the
interface has been flushed).

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org>
Reviewed-by: Marijn Suijten <marijn.suijten@somainline.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20210911163919.47173-2-angelogioacchino.delregno@somainline.org
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_cmd.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_cmd.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_cmd.c
index 56c1bd220110..d59802b67d15 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_cmd.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_cmd.c
@@ -656,6 +656,9 @@ static int dpu_encoder_phys_cmd_wait_for_commit_done(
 	if (!dpu_encoder_phys_cmd_is_master(phys_enc))
 		return 0;
 
+	if (phys_enc->hw_ctl->ops.is_started(phys_enc->hw_ctl))
+		return dpu_encoder_phys_cmd_wait_for_tx_complete(phys_enc);
+
 	return _dpu_encoder_phys_cmd_wait_for_ctl_start(phys_enc);
 }
 
-- 
2.38.1