diff options
Diffstat (limited to 'drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c')
| -rw-r--r-- | drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c | 31 |
1 files changed, 20 insertions, 11 deletions
diff --git a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c index acbd7eb66cbe..036f504ac7db 100644 --- a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c +++ b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c @@ -52,17 +52,11 @@ static void set_aux_backlight_enable(struct intel_dp *intel_dp, bool enable) } } -/* - * Read the current backlight value from DPCD register(s) based - * on if 8-bit(MSB) or 16-bit(MSB and LSB) values are supported - */ -static u32 intel_dp_aux_get_backlight(struct intel_connector *connector) +static bool intel_dp_aux_backlight_dpcd_mode(struct intel_connector *connector) { struct intel_dp *intel_dp = intel_attached_dp(connector); struct drm_i915_private *i915 = dp_to_i915(intel_dp); - u8 read_val[2] = { 0x0 }; u8 mode_reg; - u16 level = 0; if (drm_dp_dpcd_readb(&intel_dp->aux, DP_EDP_BACKLIGHT_MODE_SET_REGISTER, @@ -70,15 +64,29 @@ static u32 intel_dp_aux_get_backlight(struct intel_connector *connector) drm_dbg_kms(&i915->drm, "Failed to read the DPCD register 0x%x\n", DP_EDP_BACKLIGHT_MODE_SET_REGISTER); - return 0; + return false; } + return (mode_reg & DP_EDP_BACKLIGHT_CONTROL_MODE_MASK) == + DP_EDP_BACKLIGHT_CONTROL_MODE_DPCD; +} + +/* + * Read the current backlight value from DPCD register(s) based + * on if 8-bit(MSB) or 16-bit(MSB and LSB) values are supported + */ +static u32 intel_dp_aux_get_backlight(struct intel_connector *connector) +{ + struct intel_dp *intel_dp = intel_attached_dp(connector); + struct drm_i915_private *i915 = dp_to_i915(intel_dp); + u8 read_val[2] = { 0x0 }; + u16 level = 0; + /* * If we're not in DPCD control mode yet, the programmed brightness * value is meaningless and we should assume max brightness */ - if ((mode_reg & DP_EDP_BACKLIGHT_CONTROL_MODE_MASK) != - DP_EDP_BACKLIGHT_CONTROL_MODE_DPCD) + if (!intel_dp_aux_backlight_dpcd_mode(connector)) return connector->panel.backlight.max; if (drm_dp_dpcd_read(&intel_dp->aux, DP_EDP_BACKLIGHT_BRIGHTNESS_MSB, @@ -319,7 +327,8 @@ static int intel_dp_aux_setup_backlight(struct intel_connector *connector, panel->backlight.min = 0; panel->backlight.level = intel_dp_aux_get_backlight(connector); - panel->backlight.enabled = panel->backlight.level != 0; + panel->backlight.enabled = intel_dp_aux_backlight_dpcd_mode(connector) && + panel->backlight.level != 0; return 0; } |