[PATCH 07/17] drm/amd/display: Fix brightness level not retained over reboot

[Mario Limonciello]

On 11/1/2024 14:48, Mohamed, Zaeem wrote:
> [AMD Official Use Only - AMD Internal Distribution Only]
> 
> Hi Mario,
> 
> Do I need to re-send the patch to amd-gfx after the tags have been added or is sending upstream enough?
> 
> Zaeem

Zaeem,

No need to resend to amd-gfx, they can be added when they're committed.

If you use "b4" [1] to apply them it will automatically pick them up. 
If they're applied manually then the person applying them can manually 
apply the tags too.

[1] https://b4.docs.kernel.org/en/latest/
> 
> -----Original Message-----
> From: Limonciello, Mario <Mario.Limonciello at amd.com>
> Sent: Friday, November 1, 2024 11:43 AM
> To: Mohamed, Zaeem <Zaeem.Mohamed at amd.com>; amd-gfx at lists.freedesktop.org
> Cc: Wentland, Harry <Harry.Wentland at amd.com>; Li, Sun peng (Leo) <Sunpeng.Li at amd.com>; Siqueira, Rodrigo <Rodrigo.Siqueira at amd.com>; Mahfooz, Hamza <Hamza.Mahfooz at amd.com>; Pillai, Aurabindo <Aurabindo.Pillai at amd.com>; Li, Roman <Roman.Li at amd.com>; Lin, Wayne <Wayne.Lin at amd.com>; Chung, ChiaHsuan (Tom) <ChiaHsuan.Chung at amd.com>; Zuo, Jerry <Jerry.Zuo at amd.com>; Chiu, Solomon <Solomon.Chiu at amd.com>; Wheeler, Daniel <Daniel.Wheeler at amd.com>; mark.herbert42 at gmail.com
> Subject: Re: [PATCH 07/17] drm/amd/display: Fix brightness level not retained over reboot
> 
> On 11/1/2024 08:49, Zaeem Mohamed wrote:
>> From: Tom Chung <chiahsuan.chung at amd.com>
>>
>> [Why]
>> During boot up and resume the DC layer will reset the panel brightness
>> to fix a flicker issue.
>>
>> It will cause the dm->actual_brightness is not the current panel
>> brightness level. (the dm->brightness is the correct panel level)
>>
>> [How]
>> Set the backlight level after do the set mode.
>>
>> Reviewed-by: Sun peng Li <sunpeng.li at amd.com>
>> Signed-off-by: Tom Chung <chiahsuan.chung at amd.com>
>> Signed-off-by: Zaeem Mohamed <zaeem.mohamed at amd.com>
> 
> Some more tags, please explicitly add these while merging.
> 
> Cc: stable at vger.kernel.org
> Fixes: d9e865826c20 ("drm/amd/display: Simplify brightness initialization")
> Reported-by: Mark Herbert <mark.herbert42 at gmail.com>
> Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3655
> 
>> ---
>>    drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 15 +++++++++++++++
>>    1 file changed, 15 insertions(+)
>>
>> 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 bbfc47f6595f..2599a99509de 100644
>> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
>> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
>> @@ -9411,6 +9411,7 @@ static void amdgpu_dm_commit_streams(struct drm_atomic_state *state,
>>        bool mode_set_reset_required = false;
>>        u32 i;
>>        struct dc_commit_streams_params params = {dc_state->streams,
>> dc_state->stream_count};
>> +     bool set_backlight_level = false;
>>
>>        /* Disable writeback */
>>        for_each_old_connector_in_state(state, connector, old_con_state, i)
>> { @@ -9530,6 +9531,7 @@ static void amdgpu_dm_commit_streams(struct drm_atomic_state *state,
>>                        acrtc->hw_mode = new_crtc_state->mode;
>>                        crtc->hwmode = new_crtc_state->mode;
>>                        mode_set_reset_required = true;
>> +                     set_backlight_level = true;
>>                } else if (modereset_required(new_crtc_state)) {
>>                        drm_dbg_atomic(dev,
>>                                       "Atomic commit: RESET. crtc id %d:[%p]\n", @@ -9581,6
>> +9583,19 @@ static void amdgpu_dm_commit_streams(struct drm_atomic_state *state,
>>                                acrtc->otg_inst = status->primary_otg_inst;
>>                }
>>        }
>> +
>> +     /* During boot up and resume the DC layer will reset the panel brightness
>> +      * to fix a flicker issue.
>> +      * It will cause the dm->actual_brightness is not the current panel brightness
>> +      * level. (the dm->brightness is the correct panel level)
>> +      * So we set the backlight level with dm->brightness value after set mode
>> +      */
>> +     if (set_backlight_level) {
>> +             for (i = 0; i < dm->num_of_edps; i++) {
>> +                     if (dm->backlight_dev[i])
>> +                             amdgpu_dm_backlight_set_level(dm, i, dm->brightness[i]);
>> +             }
>> +     }
>>    }
>>
>>    static void dm_set_writeback(struct amdgpu_display_manager *dm,
>