Add option to allow choosing how to adjust brightness if panel supports both PWM pin and AUX channel.
Signed-off-by: Puthikorn Voravootivat puthik@chromium.org --- drivers/gpu/drm/i915/i915_params.c | 8 +++++--- drivers/gpu/drm/i915/i915_params.h | 2 +- drivers/gpu/drm/i915/intel_dp_aux_backlight.c | 26 ++++++++++++++++++++++---- 3 files changed, 28 insertions(+), 8 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_params.c b/drivers/gpu/drm/i915/i915_params.c index b6a7e363d076..13cf3f1572ab 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, };
@@ -246,9 +246,11 @@ MODULE_PARM_DESC(enable_dp_mst, module_param_named_unsafe(inject_load_failure, i915.inject_load_failure, uint, 0400); 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_param_named(enable_dpcd_backlight, i915.enable_dpcd_backlight, int, 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 a0995c00fc84..16ba1924308d 100644 --- a/drivers/gpu/drm/i915/intel_dp_aux_backlight.c +++ b/drivers/gpu/drm/i915/intel_dp_aux_backlight.c @@ -43,6 +43,9 @@ static void set_aux_backlight_enable(struct intel_dp *intel_dp, bool enable) else reg_val &= ~(DP_EDP_BACKLIGHT_ENABLE);
+ /* TODO: If the panel also support enabling backlight via BL_ENABLE pin, + * the backlight will be enabled again in _intel_edp_backlight_on() + */ if (drm_dp_dpcd_writeb(&intel_dp->aux, DP_EDP_DISPLAY_CONTROL_REGISTER, reg_val) != 1) { DRM_DEBUG_KMS("Failed to %s aux backlight\n", @@ -168,20 +171,35 @@ intel_dp_aux_display_control_capable(struct intel_connector *connector) /* Check the eDP Display control capabilities registers to determine if * the panel can support backlight control over the aux channel */ - if (intel_dp->edp_dpcd[1] & DP_EDP_TCON_BACKLIGHT_ADJUSTMENT_CAP && - (intel_dp->edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_AUX_SET_CAP) && - !(intel_dp->edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_PWM_PIN_CAP)) { + if ((intel_dp->edp_dpcd[1] & DP_EDP_TCON_BACKLIGHT_ADJUSTMENT_CAP) && + (intel_dp->edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_AUX_SET_CAP)) { DRM_DEBUG_KMS("AUX Backlight Control Supported!\n"); return true; } 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[1] & DP_EDP_TCON_BACKLIGHT_ADJUSTMENT_CAP) && + (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))