drm/amd/display: Detach backlight from stream

[Why]
Backlight is conceptually a property of links, not streams.
All backlight programming is done on links, but there is a
stream property bl_pwm_level that is used to restore backlight
on dpms on and s3 resume.  This is unnecessary, as backlight
is already restored by hardware with no driver intervention.

[How]
Remove bl_pwm_level, and the stream argument to set_backlight

Bug: https://bugs.freedesktop.org/show_bug.cgi?id=109375
Signed-off-by: David Francis <David.Francis@amd.com>
Reviewed-by: Harry Wentland <Harry.Wentland@amd.com>
Acked-by: Anthony Koo <Anthony.Koo@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 923fe4951282cbdfce05186c10380bbc45b5e03b)

4 files changed, 3 insertions, 15 deletions

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 903dbafc144d..f4fa40c387d3 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -1772,7 +1772,7 @@ static int amdgpu_dm_backlight_update_status(struct backlight_device *bd)
                 + caps.min_input_signal * 0x101;
 
         if (dc_link_set_backlight_level(dm->backlight_link,
-                        brightness, 0, 0))
+                        brightness, 0))
                 return 0;
         else
                 return 1;
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 52deacf39841..b0265dbebd4c 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
@@ -2190,8 +2190,7 @@ int dc_link_get_backlight_level(const struct dc_link *link)
 
 bool dc_link_set_backlight_level(const struct dc_link *link,
                 uint32_t backlight_pwm_u16_16,
-                uint32_t frame_ramp,
-                const struct dc_stream_state *stream)
+                uint32_t frame_ramp)
 {
         struct dc  *core_dc = link->ctx->dc;
         struct abm *abm = core_dc->res_pool->abm;
@@ -2206,10 +2205,6 @@ bool dc_link_set_backlight_level(const struct dc_link *link,
                 (abm->funcs->set_backlight_level_pwm == NULL))
                 return false;
 
-        if (stream)
-                ((struct dc_stream_state *)stream)->bl_pwm_level =
-                                backlight_pwm_u16_16;
-
         use_smooth_brightness = dmcu->funcs->is_dmcu_initialized(dmcu);
 
         DC_LOG_BACKLIGHT("New Backlight level: %d (0x%X)\n",
@@ -2637,11 +2632,6 @@ void core_link_enable_stream(
 
                 if (dc_is_dp_signal(pipe_ctx->stream->signal))
                         enable_stream_features(pipe_ctx);
-
-                dc_link_set_backlight_level(pipe_ctx->stream->sink->link,
-                                pipe_ctx->stream->bl_pwm_level,
-                                0,
-                                pipe_ctx->stream);
         }
 
 }
diff --git a/drivers/gpu/drm/amd/display/dc/dc_link.h b/drivers/gpu/drm/amd/display/dc/dc_link.h
index 29f19d57ff7a..b2243e0dad1f 100644
--- a/drivers/gpu/drm/amd/display/dc/dc_link.h
+++ b/drivers/gpu/drm/amd/display/dc/dc_link.h
@@ -146,8 +146,7 @@ static inline struct dc_link *dc_get_link_at_index(struct dc *dc, uint32_t link_
  */
 bool dc_link_set_backlight_level(const struct dc_link *dc_link,
                 uint32_t backlight_pwm_u16_16,
-                uint32_t frame_ramp,
-                const struct dc_stream_state *stream);
+                uint32_t frame_ramp);
 
 int dc_link_get_backlight_level(const struct dc_link *dc_link);
 
diff --git a/drivers/gpu/drm/amd/display/dc/dc_stream.h b/drivers/gpu/drm/amd/display/dc/dc_stream.h
index be34d638e15d..d70c9e1cda3d 100644
--- a/drivers/gpu/drm/amd/display/dc/dc_stream.h
+++ b/drivers/gpu/drm/amd/display/dc/dc_stream.h
@@ -91,7 +91,6 @@ struct dc_stream_state {
 
         /* DMCU info */
         unsigned int abm_level;
-        unsigned int bl_pwm_level;
 
         /* from core_stream struct */
         struct dc_context *ctx;