drm/i915: make backlight functions take a connector

On VLV/BYT, backlight controls a per-pipe, so when adjusting the
backlight we need to pass the correct info.  So make the externally
visible backlight functions take a connector argument, which can be used
internally to figure out the pipe backlight to adjust.

v2: make connector pipe lookup check for NULL crtc (Jani)
    fixup connector check in ASLE code (Jani)
v3: make sure we take the mode config lock around lookups (Daniel)
v4: fix double unlock in panel_get_brightness (Daniel)
v5: push ASLE work into a work queue (Daniel)
v6: separate ASLE work to a prep patch, rebase (Jani)

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/i915_drv.h

@@ -54,6 +54,7 @@
 #define DRIVER_DATE		"20080730"
 
 enum pipe {
+	INVALID_PIPE = -1,
 	PIPE_A = 0,
 	PIPE_B,
 	PIPE_C,

drivers/gpu/drm/i915/intel_display.c

@@ -9874,6 +9874,18 @@ static void intel_crtc_init(struct drm_device *dev, int pipe)
 	drm_crtc_helper_add(&intel_crtc->base, &intel_helper_funcs);
 }
 
+enum pipe intel_get_pipe_from_connector(struct intel_connector *connector)
+{
+	struct drm_encoder *encoder = connector->base.encoder;
+
+	WARN_ON(!mutex_is_locked(&connector->base.dev->mode_config.mutex));
+
+	if (!encoder)
+		return INVALID_PIPE;
+
+	return to_intel_crtc(encoder->crtc)->pipe;
+}
+
 int intel_get_pipe_from_crtc_id(struct drm_device *dev, void *data,
 				struct drm_file *file)
 {

drivers/gpu/drm/i915/intel_dp.c

@@ -1249,7 +1249,6 @@ void ironlake_edp_backlight_on(struct intel_dp *intel_dp)
 	struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
 	struct drm_device *dev = intel_dig_port->base.base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
-	int pipe = to_intel_crtc(intel_dig_port->base.base.crtc)->pipe;
 	u32 pp;
 	u32 pp_ctrl_reg;
 
@@ -1272,7 +1271,7 @@ void ironlake_edp_backlight_on(struct intel_dp *intel_dp)
 	I915_WRITE(pp_ctrl_reg, pp);
 	POSTING_READ(pp_ctrl_reg);
 
-	intel_panel_enable_backlight(dev, pipe);
+	intel_panel_enable_backlight(intel_dp->attached_connector);
 }
 
 void ironlake_edp_backlight_off(struct intel_dp *intel_dp)
@@ -1285,7 +1284,7 @@ void ironlake_edp_backlight_off(struct intel_dp *intel_dp)
 	if (!is_edp(intel_dp))
 		return;
 
-	intel_panel_disable_backlight(dev);
+	intel_panel_disable_backlight(intel_dp->attached_connector);
 
 	DRM_DEBUG_KMS("\n");
 	pp = ironlake_get_pp_control(intel_dp);

drivers/gpu/drm/i915/intel_drv.h

@@ -630,6 +630,7 @@ void intel_connector_attach_encoder(struct intel_connector *connector,
 struct drm_encoder *intel_best_encoder(struct drm_connector *connector);
 struct drm_display_mode *intel_crtc_mode_get(struct drm_device *dev,
 					     struct drm_crtc *crtc);
+enum pipe intel_get_pipe_from_connector(struct intel_connector *connector);
 int intel_get_pipe_from_crtc_id(struct drm_device *dev, void *data,
 				struct drm_file *file_priv);
 enum transcoder intel_pipe_to_cpu_transcoder(struct drm_i915_private *dev_priv,
@@ -802,10 +803,11 @@ void intel_pch_panel_fitting(struct intel_crtc *crtc,
 void intel_gmch_panel_fitting(struct intel_crtc *crtc,
 			      struct intel_crtc_config *pipe_config,
 			      int fitting_mode);
-void intel_panel_set_backlight(struct drm_device *dev, u32 level, u32 max);
+void intel_panel_set_backlight(struct intel_connector *connector, u32 level,
+			       u32 max);
 int intel_panel_setup_backlight(struct drm_connector *connector);
-void intel_panel_enable_backlight(struct drm_device *dev, enum pipe pipe);
-void intel_panel_disable_backlight(struct drm_device *dev);
+void intel_panel_enable_backlight(struct intel_connector *connector);
+void intel_panel_disable_backlight(struct intel_connector *connector);
 void intel_panel_destroy_backlight(struct drm_device *dev);
 enum drm_connector_status intel_panel_detect(struct drm_device *dev);
 

drivers/gpu/drm/i915/intel_lvds.c

@@ -206,7 +206,8 @@ static void intel_enable_lvds(struct intel_encoder *encoder)
 {
 	struct drm_device *dev = encoder->base.dev;
 	struct intel_lvds_encoder *lvds_encoder = to_lvds_encoder(&encoder->base);
-	struct intel_crtc *intel_crtc = to_intel_crtc(encoder->base.crtc);
+	struct intel_connector *intel_connector =
+		&lvds_encoder->attached_connector->base;
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	u32 ctl_reg, stat_reg;
 
@@ -225,13 +226,15 @@ static void intel_enable_lvds(struct intel_encoder *encoder)
 	if (wait_for((I915_READ(stat_reg) & PP_ON) != 0, 1000))
 		DRM_ERROR("timed out waiting for panel to power on\n");
 
-	intel_panel_enable_backlight(dev, intel_crtc->pipe);
+	intel_panel_enable_backlight(intel_connector);
 }
 
 static void intel_disable_lvds(struct intel_encoder *encoder)
 {
 	struct drm_device *dev = encoder->base.dev;
 	struct intel_lvds_encoder *lvds_encoder = to_lvds_encoder(&encoder->base);
+	struct intel_connector *intel_connector =
+		&lvds_encoder->attached_connector->base;
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	u32 ctl_reg, stat_reg;
 
@@ -243,7 +246,7 @@ static void intel_disable_lvds(struct intel_encoder *encoder)
 		stat_reg = PP_STATUS;
 	}
 
-	intel_panel_disable_backlight(dev);
+	intel_panel_disable_backlight(intel_connector);
 
 	I915_WRITE(ctl_reg, I915_READ(ctl_reg) & ~POWER_TARGET_ON);
 	if (wait_for((I915_READ(stat_reg) & PP_ON) == 0, 1000))

drivers/gpu/drm/i915/intel_opregion.c

@@ -396,7 +396,13 @@ int intel_opregion_notify_adapter(struct drm_device *dev, pci_power_t state)
 static u32 asle_set_backlight(struct drm_device *dev, u32 bclp)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
+	struct drm_encoder *encoder;
+	struct drm_connector *connector;
+	struct intel_connector *intel_connector = NULL;
+	struct drm_crtc *crtc = dev_priv->pipe_to_crtc_mapping[0];
 	struct opregion_asle __iomem *asle = dev_priv->opregion.asle;
+	u32 ret = 0;
+	bool found = false;
 
 	DRM_DEBUG_DRIVER("bclp = 0x%08x\n", bclp);
 
@@ -407,11 +413,39 @@ static u32 asle_set_backlight(struct drm_device *dev, u32 bclp)
 	if (bclp > 255)
 		return ASLC_BACKLIGHT_FAILED;
 
+	mutex_lock(&dev->mode_config.mutex);
+	/*
+	 * Could match the OpRegion connector here instead, but we'd also need
+	 * to verify the connector could handle a backlight call.
+	 */
+	list_for_each_entry(encoder, &dev->mode_config.encoder_list, head)
+		if (encoder->crtc == crtc) {
+			found = true;
+			break;
+		}
+
+	if (!found) {
+		ret = ASLC_BACKLIGHT_FAILED;
+		goto out;
+	}
+
+	list_for_each_entry(connector, &dev->mode_config.connector_list, head)
+		if (connector->encoder == encoder)
+			intel_connector = to_intel_connector(connector);
+
+	if (!intel_connector) {
+		ret = ASLC_BACKLIGHT_FAILED;
+		goto out;
+	}
+
 	DRM_DEBUG_KMS("updating opregion backlight %d/255\n", bclp);
-	intel_panel_set_backlight(dev, bclp, 255);
+	intel_panel_set_backlight(intel_connector, bclp, 255);
 	iowrite32(DIV_ROUND_UP(bclp * 100, 255) | ASLE_CBLV_VALID, &asle->cblv);
 
-	return 0;
+out:
+	mutex_unlock(&dev->mode_config.mutex);
+
+	return ret;
 }
 
 static u32 asle_set_als_illum(struct drm_device *dev, u32 alsi)