[PATCH] drm/amd/display: fix ABM disablement

[Hamza Mahfooz]

On 11/22/23 17:45, Pillai, Aurabindo wrote:
> [AMD Official Use Only - General]
> 
> 
> Does amdgpu_dm_connector_funcs_reset() get called on wakeup from suspend

According to my research/testing drm_connector's rest() callback only
gets called when the connector gets created.

> ?  Users would want the system to have the same brightness level before 
> suspending.
> 
> 
> --
> 
> Regards,
> Jay
> ------------------------------------------------------------------------
> *From:* Mahfooz, Hamza <Hamza.Mahfooz at amd.com>
> *Sent:* Wednesday, November 22, 2023 5:24 PM
> *To:* amd-gfx at lists.freedesktop.org <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>; 
> Koenig, Christian <Christian.Koenig at amd.com>; Hung, Alex 
> <Alex.Hung at amd.com>; Pillai, Aurabindo <Aurabindo.Pillai at amd.com>; Wu, 
> Hersen <hersenxs.wu at amd.com>; Lin, Wayne <Wayne.Lin at amd.com>; Mahfooz, 
> Hamza <Hamza.Mahfooz at amd.com>
> *Subject:* [PATCH] drm/amd/display: fix ABM disablement
> On recent versions of DMUB firmware, if we want to completely disable
> ABM we have to pass ABM_LEVEL_IMMEDIATE_DISABLE as the requested ABM
> level to DMUB. Otherwise, LCD eDP displays are unable to reach their
> maximum brightness levels. So, to fix this whenever the user requests an
> ABM level of 0 pass ABM_LEVEL_IMMEDIATE_DISABLE to DMUB instead. Also,
> to keep the user's experience consistent map ABM_LEVEL_IMMEDIATE_DISABLE
> to 0 when a user tries to read the requested ABM level.
> 
> Signed-off-by: Hamza Mahfooz <hamza.mahfooz at amd.com>
> ---
>   drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 8 +++++---
>   1 file changed, 5 insertions(+), 3 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 5d9496db0ecb..8cb92d941cd9 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> @@ -6230,7 +6230,7 @@ int amdgpu_dm_connector_atomic_set_property(struct 
> drm_connector *connector,
>                   dm_new_state->underscan_enable = val;
>                   ret = 0;
>           } else if (property == adev->mode_info.abm_level_property) {
> -               dm_new_state->abm_level = val;
> +               dm_new_state->abm_level = val ?: 
> ABM_LEVEL_IMMEDIATE_DISABLE;
>                   ret = 0;
>           }
> 
> @@ -6275,7 +6275,8 @@ int amdgpu_dm_connector_atomic_get_property(struct 
> drm_connector *connector,
>                   *val = dm_state->underscan_enable;
>                   ret = 0;
>           } else if (property == adev->mode_info.abm_level_property) {
> -               *val = dm_state->abm_level;
> +               *val = (dm_state->abm_level != 
> ABM_LEVEL_IMMEDIATE_DISABLE) ?
> +                       dm_state->abm_level : 0;
>                   ret = 0;
>           }
> 
> @@ -6348,7 +6349,8 @@ void amdgpu_dm_connector_funcs_reset(struct 
> drm_connector *connector)
>                   state->pbn = 0;
> 
>                   if (connector->connector_type == DRM_MODE_CONNECTOR_eDP)
> -                       state->abm_level = amdgpu_dm_abm_level;
> +                       state->abm_level = amdgpu_dm_abm_level ?:
> +                               ABM_LEVEL_IMMEDIATE_DISABLE;
> 
>                   __drm_atomic_helper_connector_reset(connector, 
> &state->base);
>           }
> -- 
> 2.42.1
> 
-- 
Hamza