Add option to allow choosing how to adjust brightness if panel supports both PWM pin and AUX channel. Signed-off-by: Puthikorn Voravootivat <puthik@xxxxxxxxxxxx> --- drivers/gpu/drm/i915/i915_params.c | 6 ++++-- drivers/gpu/drm/i915/i915_params.h | 2 +- drivers/gpu/drm/i915/intel_dp_aux_backlight.c | 17 ++++++++++++++++- 3 files changed, 21 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_params.c b/drivers/gpu/drm/i915/i915_params.c index b6a7e363d076..323d12badace 100644 --- a/drivers/gpu/drm/i915/i915_params.c +++ b/drivers/gpu/drm/i915/i915_params.c @@ -63,7 +63,7 @@ struct i915_params i915 __read_mostly = { .huc_firmware_path = NULL, .enable_dp_mst = true, .inject_load_failure = 0, - .enable_dpcd_backlight = false, + .enable_dpcd_backlight = -1, .enable_gvt = false, }; @@ -248,7 +248,9 @@ MODULE_PARM_DESC(inject_load_failure, "Force an error after a number of failure check points (0:disabled (default), N:force failure at the Nth failure check point)"); module_param_named(enable_dpcd_backlight, i915.enable_dpcd_backlight, bool, 0600); MODULE_PARM_DESC(enable_dpcd_backlight, - "Enable support for DPCD backlight control (default:false)"); + "Enable support for DPCD backlight control " + "(-1:disable (default), 0:Use PWM pin if both supported, " + "1:Use DPCD if both supported"); module_param_named(enable_gvt, i915.enable_gvt, bool, 0400); MODULE_PARM_DESC(enable_gvt, diff --git a/drivers/gpu/drm/i915/i915_params.h b/drivers/gpu/drm/i915/i915_params.h index 34148cc8637c..ac02efce6e22 100644 --- a/drivers/gpu/drm/i915/i915_params.h +++ b/drivers/gpu/drm/i915/i915_params.h @@ -66,7 +66,7 @@ func(bool, verbose_state_checks); \ func(bool, nuclear_pageflip); \ func(bool, enable_dp_mst); \ - func(bool, enable_dpcd_backlight); \ + func(int, enable_dpcd_backlight); \ func(bool, enable_gvt) #define MEMBER(T, member) T member diff --git a/drivers/gpu/drm/i915/intel_dp_aux_backlight.c b/drivers/gpu/drm/i915/intel_dp_aux_backlight.c index 5b83c9737644..e82f7cb9a7af 100644 --- a/drivers/gpu/drm/i915/intel_dp_aux_backlight.c +++ b/drivers/gpu/drm/i915/intel_dp_aux_backlight.c @@ -175,11 +175,26 @@ intel_dp_aux_display_control_capable(struct intel_connector *connector) return false; } +static bool +intel_dp_pwm_pin_display_control_capable(struct intel_connector *connector) +{ + struct intel_dp *intel_dp = enc_to_intel_dp(&connector->encoder->base); + + /* Check the eDP Display control capabilities registers to determine if + * the panel can support backlight control via BL_PWM_DIM eDP pin + */ + return intel_dp->edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_PWM_PIN_CAP; +} + int intel_dp_aux_init_backlight_funcs(struct intel_connector *intel_connector) { struct intel_panel *panel = &intel_connector->panel; - if (!i915.enable_dpcd_backlight) + if (i915.enable_dpcd_backlight == -1) + return -ENODEV; + + if (i915.enable_dpcd_backlight == 0 && + intel_dp_pwm_pin_display_control_capable(intel_connector)) return -ENODEV; if (!intel_dp_aux_display_control_capable(intel_connector)) -- 2.13.0.rc1.294.g07d810a77f-goog _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel