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| author | Iswara Nagulendran <Iswara.Nagulendran@amd.com> | 2023-03-16 16:29:06 -0400 |
|---|---|---|
| committer | Alex Deucher <alexander.deucher@amd.com> | 2023-04-18 16:28:52 -0400 |
| commit | 4d5f872dbc755114628c236e17421629ec522203 (patch) | |
| tree | 4bf888b79880667294ffba16e1c976f0da09b11c /drivers/gpu/drm/amd/display/dc/link/protocols | |
| parent | e3416e872f84086667df21daf166506fab97358d (diff) | |
| download | linux-stable-4d5f872dbc755114628c236e17421629ec522203.tar.gz linux-stable-4d5f872dbc755114628c236e17421629ec522203.tar.bz2 linux-stable-4d5f872dbc755114628c236e17421629ec522203.zip | |
drm/amd/display: Adding support for VESA SCR
[HOW&WHY]
Write DPCD 721 bit 7 to high, and
the appropriate luminance level
to DPCD 734-736 if bit 4 from DPCD register
734 is high, indicating that the panel
luminance control is enabled from the panel side.
Reviewed-by: Anthony Koo <Anthony.Koo@amd.com>
Acked-by: Qingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: Iswara Nagulendran <Iswara.Nagulendran@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/link/protocols')
| -rw-r--r-- | drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c | 9 | ||||
| -rw-r--r-- | drivers/gpu/drm/amd/display/dc/link/protocols/link_edp_panel_control.c | 29 |
2 files changed, 33 insertions, 5 deletions
diff --git a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c index 5ff5d4e64902..84265dc66bba 100644 --- a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c +++ b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c @@ -1450,7 +1450,8 @@ bool read_is_mst_supported(struct dc_link *link) */ static bool dpcd_read_sink_ext_caps(struct dc_link *link) { - uint8_t dpcd_data; + uint8_t dpcd_data = 0; + uint8_t edp_general_cap2 = 0; if (!link) return false; @@ -1459,6 +1460,12 @@ static bool dpcd_read_sink_ext_caps(struct dc_link *link) return false; link->dpcd_sink_ext_caps.raw = dpcd_data; + + if (core_link_read_dpcd(link, DP_EDP_GENERAL_CAP_2, &edp_general_cap2, 1) != DC_OK) + return false; + + link->dpcd_caps.panel_luminance_control = (edp_general_cap2 & DP_EDP_PANEL_LUMINANCE_CONTROL_CAPABLE) != 0; + return true; } diff --git a/drivers/gpu/drm/amd/display/dc/link/protocols/link_edp_panel_control.c b/drivers/gpu/drm/amd/display/dc/link/protocols/link_edp_panel_control.c index d895046787bc..5ab2de12ccf8 100644 --- a/drivers/gpu/drm/amd/display/dc/link/protocols/link_edp_panel_control.c +++ b/drivers/gpu/drm/amd/display/dc/link/protocols/link_edp_panel_control.c @@ -164,14 +164,35 @@ bool edp_set_backlight_level_nits(struct dc_link *link, *(uint16_t *)&dpcd_backlight_set.backlight_transition_time_ms = (uint16_t)transition_time_in_ms; - if (core_link_write_dpcd(link, DP_SOURCE_BACKLIGHT_LEVEL, + if (!link->dpcd_caps.panel_luminance_control) { + if (core_link_write_dpcd(link, DP_SOURCE_BACKLIGHT_LEVEL, (uint8_t *)(&dpcd_backlight_set), sizeof(dpcd_backlight_set)) != DC_OK) - return false; + return false; - if (core_link_write_dpcd(link, DP_SOURCE_BACKLIGHT_CONTROL, + if (core_link_write_dpcd(link, DP_SOURCE_BACKLIGHT_CONTROL, &backlight_control, 1) != DC_OK) - return false; + return false; + } else { + const uint8_t backlight_enable = DP_EDP_PANEL_LUMINANCE_CONTROL_ENABLE; + struct target_luminance_value *target_luminance = NULL; + + //if target luminance value is greater than 24 bits, clip the value to 24 bits + if (backlight_millinits > 0xFFFFFF) + backlight_millinits = 0xFFFFFF; + + target_luminance = (struct target_luminance_value *)&backlight_millinits; + + if (core_link_write_dpcd(link, DP_EDP_BACKLIGHT_MODE_SET_REGISTER, + &backlight_enable, + sizeof(backlight_enable)) != DC_OK) + return false; + + if (core_link_write_dpcd(link, DP_EDP_PANEL_TARGET_LUMINANCE_VALUE, + (uint8_t *)(target_luminance), + sizeof(struct target_luminance_value)) != DC_OK) + return false; + } return true; } |