[PATCH 27/28] drm/amd/display: Fixed dim around 1sec when resume from S3

[Harry Wentland]

From: Yongqiang Sun <yongqiang.sun at amd.com>

root cause:
DMCU try to perform a smoothness brightness change.Incorrect initial
brightness level causes the 1 sec dim.
Change:
Cache brightness level in stream, and clear it when edp backlight on.
If brightness level in stream is 0, set brightness with ramp value is 0.
DMCU will set the brightness without smoothness transition.

Signed-off-by: Yongqiang Sun <yongqiang.sun at amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng at amd.com>
Acked-by: Harry Wentland <harry.wentland at amd.com>
---
 drivers/gpu/drm/amd/display/dc/core/dc_link.c               | 5 +++++
 drivers/gpu/drm/amd/display/dc/dc_stream.h                  | 1 +
 drivers/gpu/drm/amd/display/dc/dce110/dce110_hw_sequencer.c | 4 +++-
 3 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link.c b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
index f8c09273e0f1..e6d5dcb35e96 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
@@ -1960,6 +1960,11 @@ bool dc_link_set_backlight_level(const struct dc_link *link, uint32_t level,
 		(abm->funcs->set_backlight_level == NULL))
 		return false;
 
+	if (stream->bl_pwm_level == 0)
+		frame_ramp = 0;
+
+	((struct dc_stream_state *)stream)->bl_pwm_level = level;
+
 	use_smooth_brightness = dmcu->funcs->is_dmcu_initialized(dmcu);
 
 	DC_LOG_BACKLIGHT("New Backlight level: %d (0x%X)\n", level, level);
diff --git a/drivers/gpu/drm/amd/display/dc/dc_stream.h b/drivers/gpu/drm/amd/display/dc/dc_stream.h
index 13e5ac9cfe13..d017df56b2ba 100644
--- a/drivers/gpu/drm/amd/display/dc/dc_stream.h
+++ b/drivers/gpu/drm/amd/display/dc/dc_stream.h
@@ -78,6 +78,7 @@ struct dc_stream_state {
 
 	/* DMCU info */
 	unsigned int abm_level;
+	unsigned int bl_pwm_level;
 
 	/* from core_stream struct */
 	struct dc_context *ctx;
diff --git a/drivers/gpu/drm/amd/display/dc/dce110/dce110_hw_sequencer.c b/drivers/gpu/drm/amd/display/dc/dce110/dce110_hw_sequencer.c
index 3e9cd1b7f32c..30dd62f0f5fa 100644
--- a/drivers/gpu/drm/amd/display/dc/dce110/dce110_hw_sequencer.c
+++ b/drivers/gpu/drm/amd/display/dc/dce110/dce110_hw_sequencer.c
@@ -1006,8 +1006,10 @@ void dce110_unblank_stream(struct pipe_ctx *pipe_ctx,
 	if (dc_is_dp_signal(pipe_ctx->stream->signal))
 		pipe_ctx->stream_res.stream_enc->funcs->dp_unblank(pipe_ctx->stream_res.stream_enc, &params);
 
-	if (link->local_sink && link->local_sink->sink_signal == SIGNAL_TYPE_EDP)
+	if (link->local_sink && link->local_sink->sink_signal == SIGNAL_TYPE_EDP) {
 		link->dc->hwss.edp_backlight_control(link, true);
+		stream->bl_pwm_level = 0;
+	}
 }
 void dce110_blank_stream(struct pipe_ctx *pipe_ctx)
 {
-- 
2.14.1