From: Suraj Kandpal Date: Fri, 20 Jun 2025 06:34:33 +0000 (+0530) Subject: drm/dp: Introduce new member in drm_backlight_info X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=2af612ad42903637b11f9ddf4101f231f1ec5d1d;p=thirdparty%2Flinux.git drm/dp: Introduce new member in drm_backlight_info Introduce luminance_set flag which indicates if we can manipulate backlight using luminance value or not which is only possible after eDP v1.5. Signed-off-by: Suraj Kandpal Reviewed-by: Arun R Murthy Link: https://lore.kernel.org/r/20250620063445.3603086-2-suraj.kandpal@intel.com --- diff --git a/drivers/gpu/drm/display/drm_dp_helper.c b/drivers/gpu/drm/display/drm_dp_helper.c index 896bba2adb3ba..c63f482cdba7e 100644 --- a/drivers/gpu/drm/display/drm_dp_helper.c +++ b/drivers/gpu/drm/display/drm_dp_helper.c @@ -4261,11 +4261,15 @@ drm_edp_backlight_init(struct drm_dp_aux *aux, struct drm_edp_backlight_info *bl bl->aux_set = true; if (edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_BYTE_COUNT) bl->lsb_reg_used = true; + if ((edp_dpcd[0] & DP_EDP_15) && edp_dpcd[3] & + (DP_EDP_PANEL_LUMINANCE_CONTROL_CAPABLE)) + bl->luminance_set = true; /* Sanity check caps */ - if (!bl->aux_set && !(edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_PWM_PIN_CAP)) { + if (!bl->aux_set && !(edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_PWM_PIN_CAP) && + !bl->luminance_set) { drm_dbg_kms(aux->drm_dev, - "%s: Panel supports neither AUX or PWM brightness control? Aborting\n", + "%s: Panel does not support AUX, PWM or luminance-based brightness control. Aborting\n", aux->name); return -EINVAL; } diff --git a/include/drm/display/drm_dp_helper.h b/include/drm/display/drm_dp_helper.h index e4ca35143ff96..beafbc31f9d95 100644 --- a/include/drm/display/drm_dp_helper.h +++ b/include/drm/display/drm_dp_helper.h @@ -849,6 +849,7 @@ struct drm_edp_backlight_info { bool lsb_reg_used : 1; bool aux_enable : 1; bool aux_set : 1; + bool luminance_set : 1; }; int