drm/i915/backlight: Check Luminance based brightness control for VESA

Check if we are capable of controlling brightness via luminance
which is dependent on PANEL_LUMINANCE_CONTROL_CAPABLE bit being set
on EDP_GENERAL_CAPABILITY_2 register.

--v2
-Prefer using luminance rather than nits [Jani]
-Fix commit message

--v3
-Fix the bit name used in commit message [Arun]
-Use correct edp_dpcd[] to check the capability [Arun]

Signed-off-by: Suraj Kandpal <suraj.kandpal@intel.com>
Tested-by: Ben Kao <ben.kao@intel.com>
Reviewed-by: Arun R Murthy <arun.r.murthy@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250206063253.2827017-5-suraj.kandpal@intel.com
This commit is contained in:
Suraj Kandpal 2025-02-06 12:02:49 +05:30
parent 9535c6a4c6
commit 6448149792
2 changed files with 10 additions and 0 deletions

View File

@ -413,6 +413,7 @@ struct intel_panel {
union {
struct {
struct drm_edp_backlight_info info;
bool luminance_control_support;
} vesa;
struct {
bool sdr_uses_aux;

View File

@ -575,6 +575,15 @@ intel_dp_aux_supports_vesa_backlight(struct intel_connector *connector)
{
struct intel_display *display = to_intel_display(connector);
struct intel_dp *intel_dp = intel_attached_dp(connector);
struct intel_panel *panel = &connector->panel;
if ((intel_dp->edp_dpcd[3] & DP_EDP_PANEL_LUMINANCE_CONTROL_CAPABLE)) {
drm_dbg_kms(display->drm,
"[CONNECTOR:%d:%s] AUX Luminance Based Backlight Control Supported!\n",
connector->base.base.id, connector->base.name);
panel->backlight.edp.vesa.luminance_control_support = true;
return true;
}
if (drm_edp_backlight_supported(intel_dp->edp_dpcd)) {
drm_dbg_kms(display->drm,