[ Upstream commit c7990daebe71d11a9e360b5c3b0ecd1846a3a4bb ] [WHY] Currently we don't wait for blacklight programming completion in DMCU when setting backlight level. Some sequences such as PSR static screen event trigger reprogramming requires it to be complete. [How] Add generic wait for dmcu command completion in set backlight level. Signed-off-by: SivapiriyanKumarasamy <sivapiriyan.kumarasamy@xxxxxxx> Reviewed-by: Anthony Koo <Anthony.Koo@xxxxxxx> Acked-by: Leo Li <sunpeng.li@xxxxxxx> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/gpu/drm/amd/display/dc/dce/dce_abm.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/gpu/drm/amd/display/dc/dce/dce_abm.c b/drivers/gpu/drm/amd/display/dc/dce/dce_abm.c index 2959c3c9390b9..da30ae04e82bb 100644 --- a/drivers/gpu/drm/amd/display/dc/dce/dce_abm.c +++ b/drivers/gpu/drm/amd/display/dc/dce/dce_abm.c @@ -234,6 +234,10 @@ static void dmcu_set_backlight_level( s2 |= (backlight_8_bit << ATOM_S2_CURRENT_BL_LEVEL_SHIFT); REG_WRITE(BIOS_SCRATCH_2, s2); + + /* waitDMCUReadyForCmd */ + REG_WAIT(MASTER_COMM_CNTL_REG, MASTER_COMM_INTERRUPT, + 0, 1, 80000); } static void dce_abm_init(struct abm *abm) -- 2.20.1