From 2af612ad42903637b11f9ddf4101f231f1ec5d1d Mon Sep 17 00:00:00 2001 From: Suraj Kandpal Date: Fri, 20 Jun 2025 12:04:33 +0530 Subject: [PATCH 4232/5403] 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 --- drivers/gpu/drm/display/drm_dp_helper.c | 8 ++++++-- include/drm/display/drm_dp_helper.h | 1 + 2 files changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/display/drm_dp_helper.c b/drivers/gpu/drm/display/drm_dp_helper.c index 896bba2adb3b..c63f482cdba7 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 e4ca35143ff9..beafbc31f9d9 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 -- 2.54.0