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| author | Harry Wentland <harry.wentland@amd.com> | 2021-08-16 15:57:12 -0400 |
|---|---|---|
| committer | Alex Deucher <alexander.deucher@amd.com> | 2021-09-14 15:57:10 -0400 |
| commit | 9e0d55ae545f4a8f4c00339ad97ee2ef9e8e06ff (patch) | |
| tree | 64d28d8ac508b6b5caef1d6cc32fb22b2e254896 /drivers/gpu/drm/amd/display/dc/core/dc_link.c | |
| parent | 7b89bf83181363a84f86da787159ddbbef505b8c (diff) | |
| download | linux-9e0d55ae545f4a8f4c00339ad97ee2ef9e8e06ff.tar.bz2 | |
drm/amd/display: Get backlight from PWM if DMCU is not initialized
On Carrizo/Stoney systems we set backlight through panel_cntl, i.e.
directly via the PWM registers, if DMCU is not initialized. We
always read it back through ABM registers which leads to a
mismatch and forces atomic_commit to program the backlight
each time.
Instead make sure we use the same logic for backlight readback,
i.e. read it from panel_cntl if DMCU is not initialized.
We also need to remove some extraneous and incorrect calculations
at the end of dce_get_16_bit_backlight_from_pwm.
Bug: https://gitlab.freedesktop.org/drm/amd/-/issues/1666
Cc: stable@vger.kernel.org
Reviewed-by: Josip Pavic <josip.pavic@amd.com>
Acked-by: Mikita Lipski <mikita.lipski@amd.com>
Signed-off-by: Harry Wentland <harry.wentland@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Diffstat (limited to 'drivers/gpu/drm/amd/display/dc/core/dc_link.c')
| -rw-r--r-- | drivers/gpu/drm/amd/display/dc/core/dc_link.c | 16 |
1 files changed, 12 insertions, 4 deletions
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 3c8eb3e659af..61e49671fed5 100644 --- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c @@ -2752,13 +2752,21 @@ static struct abm *get_abm_from_stream_res(const struct dc_link *link) int dc_link_get_backlight_level(const struct dc_link *link) { - struct abm *abm = get_abm_from_stream_res(link); + struct panel_cntl *panel_cntl = link->panel_cntl; + struct dc *dc = link->ctx->dc; + struct dmcu *dmcu = dc->res_pool->dmcu; + bool fw_set_brightness = true; - if (abm == NULL || abm->funcs->get_current_backlight == NULL) - return DC_ERROR_UNEXPECTED; + if (dmcu) + fw_set_brightness = dmcu->funcs->is_dmcu_initialized(dmcu); - return (int) abm->funcs->get_current_backlight(abm); + if (!fw_set_brightness && panel_cntl->funcs->get_current_backlight) + return panel_cntl->funcs->get_current_backlight(panel_cntl); + else if (abm != NULL && abm->funcs->get_current_backlight != NULL) + return (int) abm->funcs->get_current_backlight(abm); + else + return DC_ERROR_UNEXPECTED; } int dc_link_get_target_backlight_pwm(const struct dc_link *link) |