[PATCH 1/2] drm/i915: make backlight functions take a connector v3

[PATCH 1/2] drm/i915: make backlight functions take a connector v3

[Jesse Barnes]

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)

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
---
 drivers/gpu/drm/i915/i915_drv.h       |  1 +
 drivers/gpu/drm/i915/intel_display.c  | 12 +++++
 drivers/gpu/drm/i915/intel_dp.c       |  5 +-
 drivers/gpu/drm/i915/intel_drv.h      |  8 +--
 drivers/gpu/drm/i915/intel_lvds.c     |  9 ++--
 drivers/gpu/drm/i915/intel_opregion.c | 38 +++++++++++++-
 drivers/gpu/drm/i915/intel_panel.c    | 93 +++++++++++++++++++++++++----------
 7 files changed, 129 insertions(+), 37 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index ed8653f..53a555c 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/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,
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 0ba0af4..53c4ea8 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -9729,6 +9729,18 @@ 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)
 {
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 0ed7717..6391c7d 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -1257,7 +1257,6 @@ 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;
 
@@ -1280,7 +1279,7 @@ 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)
@@ -1293,7 +1292,7 @@ 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);
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 922c5d7..476d98b 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -619,6 +619,7 @@ 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,
@@ -767,10 +768,11 @@ 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);
 
diff --git a/drivers/gpu/drm/i915/intel_lvds.c b/drivers/gpu/drm/i915/intel_lvds.c
index ae0c843..30933ab 100644
--- a/drivers/gpu/drm/i915/intel_lvds.c
+++ b/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))
diff --git a/drivers/gpu/drm/i915/intel_opregion.c b/drivers/gpu/drm/i915/intel_opregion.c
index 2acf5ca..0afaa72 100644
--- a/drivers/gpu/drm/i915/intel_opregion.c
+++ b/drivers/gpu/drm/i915/intel_opregion.c
@@ -395,6 +395,12 @@ static u32 asle_set_backlight(struct drm_device *dev, u32 bclp)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	struct opregion_asle __iomem *asle = dev_priv->opregion.asle;
+	struct drm_crtc *crtc = dev_priv->pipe_to_crtc_mapping[0];
+	struct drm_encoder *encoder;
+	struct drm_connector *connector;
+	struct intel_connector *intel_connector = NULL;
+	bool found = false;
+	int ret = 0;
 
 	DRM_DEBUG_DRIVER("bclp = 0x%08x\n", bclp);
 
@@ -405,10 +411,38 @@ static u32 asle_set_backlight(struct drm_device *dev, u32 bclp)
 	if (bclp > 255)
 		return ASLC_BACKLIGHT_FAILED;
 
-	intel_panel_set_backlight(dev, bclp, 255);
+	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_unlock;
+	}
+
+	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_unlock;
+	}
+
+	intel_panel_set_backlight(intel_connector, bclp, 255);
 	iowrite32(DIV_ROUND_UP(bclp * 100, 255) | ASLE_CBLV_VALID, &asle->cblv);
 
-	return 0;
+out_unlock:
+	mutex_unlock(&dev->mode_config.mutex);
+	return ret;
 }
 
 static u32 asle_set_als_illum(struct drm_device *dev, u32 alsi)
diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c
index 5468416..0026060 100644
--- a/drivers/gpu/drm/i915/intel_panel.c
+++ b/drivers/gpu/drm/i915/intel_panel.c
@@ -341,7 +341,7 @@ static int is_backlight_combination_mode(struct drm_device *dev)
 /* XXX: query mode clock or hardware clock and program max PWM appropriately
  * when it's 0.
  */
-static u32 i915_read_blc_pwm_ctl(struct drm_device *dev)
+static u32 i915_read_blc_pwm_ctl(struct drm_device *dev, enum pipe pipe)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	u32 val;
@@ -380,11 +380,12 @@ static u32 i915_read_blc_pwm_ctl(struct drm_device *dev)
 	return val;
 }
 
-static u32 intel_panel_get_max_backlight(struct drm_device *dev)
+static u32 intel_panel_get_max_backlight(struct drm_device *dev,
+					 enum pipe pipe)
 {
 	u32 max;
 
-	max = i915_read_blc_pwm_ctl(dev);
+	max = i915_read_blc_pwm_ctl(dev, pipe);
 
 	if (HAS_PCH_SPLIT(dev)) {
 		max >>= 16;
@@ -410,7 +411,8 @@ MODULE_PARM_DESC(invert_brightness, "Invert backlight brightness "
 	"to dri-devel@lists.freedesktop.org, if your machine needs it. "
 	"It will then be included in an upcoming module version.");
 module_param_named(invert_brightness, i915_panel_invert_brightness, int, 0600);
-static u32 intel_panel_compute_brightness(struct drm_device *dev, u32 val)
+static u32 intel_panel_compute_brightness(struct drm_device *dev,
+					  enum pipe pipe, u32 val)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 
@@ -419,7 +421,7 @@ static u32 intel_panel_compute_brightness(struct drm_device *dev, u32 val)
 
 	if (i915_panel_invert_brightness > 0 ||
 	    dev_priv->quirks & QUIRK_INVERT_BRIGHTNESS) {
-		u32 max = intel_panel_get_max_backlight(dev);
+		u32 max = intel_panel_get_max_backlight(dev, pipe);
 		if (max)
 			return max - val;
 	}
@@ -427,7 +429,8 @@ static u32 intel_panel_compute_brightness(struct drm_device *dev, u32 val)
 	return val;
 }
 
-static u32 intel_panel_get_backlight(struct drm_device *dev)
+static u32 intel_panel_get_backlight(struct drm_device *dev,
+				     enum pipe pipe)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	u32 val;
@@ -450,7 +453,7 @@ static u32 intel_panel_get_backlight(struct drm_device *dev)
 		}
 	}
 
-	val = intel_panel_compute_brightness(dev, val);
+	val = intel_panel_compute_brightness(dev, pipe, val);
 
 	spin_unlock_irqrestore(&dev_priv->backlight.lock, flags);
 
@@ -466,19 +469,19 @@ static void intel_pch_panel_set_backlight(struct drm_device *dev, u32 level)
 }
 
 static void intel_panel_actually_set_backlight(struct drm_device *dev,
-					       u32 level)
+					       enum pipe pipe, u32 level)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	u32 tmp;
 
 	DRM_DEBUG_DRIVER("set backlight PWM = %d\n", level);
-	level = intel_panel_compute_brightness(dev, level);
+	level = intel_panel_compute_brightness(dev, pipe, level);
 
 	if (HAS_PCH_SPLIT(dev))
 		return intel_pch_panel_set_backlight(dev, level);
 
 	if (is_backlight_combination_mode(dev)) {
-		u32 max = intel_panel_get_max_backlight(dev);
+		u32 max = intel_panel_get_max_backlight(dev, pipe);
 		u8 lbpc;
 
 		/* we're screwed, but keep behaviour backwards compatible */
@@ -498,15 +501,21 @@ static void intel_panel_actually_set_backlight(struct drm_device *dev,
 }
 
 /* set backlight brightness to level in range [0..max] */
-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)
 {
+	struct drm_device *dev = connector->base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
+	enum pipe pipe = intel_get_pipe_from_connector(connector);
 	u32 freq;
 	unsigned long flags;
 
+	if (pipe == INVALID_PIPE)
+		return;
+
 	spin_lock_irqsave(&dev_priv->backlight.lock, flags);
 
-	freq = intel_panel_get_max_backlight(dev);
+	freq = intel_panel_get_max_backlight(dev, pipe);
 	if (!freq) {
 		/* we are screwed, bail out */
 		goto out;
@@ -523,16 +532,21 @@ void intel_panel_set_backlight(struct drm_device *dev, u32 level, u32 max)
 		dev_priv->backlight.device->props.brightness = level;
 
 	if (dev_priv->backlight.enabled)
-		intel_panel_actually_set_backlight(dev, level);
+		intel_panel_actually_set_backlight(dev, pipe, level);
 out:
 	spin_unlock_irqrestore(&dev_priv->backlight.lock, flags);
 }
 
-void intel_panel_disable_backlight(struct drm_device *dev)
+void intel_panel_disable_backlight(struct intel_connector *connector)
 {
+	struct drm_device *dev = connector->base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
+	enum pipe pipe = intel_get_pipe_from_connector(connector);
 	unsigned long flags;
 
+	if (pipe == INVALID_PIPE)
+		return;
+
 	/*
 	 * Do not disable backlight on the vgaswitcheroo path. When switching
 	 * away from i915, the other client may depend on i915 to handle the
@@ -547,7 +561,7 @@ void intel_panel_disable_backlight(struct drm_device *dev)
 	spin_lock_irqsave(&dev_priv->backlight.lock, flags);
 
 	dev_priv->backlight.enabled = false;
-	intel_panel_actually_set_backlight(dev, 0);
+	intel_panel_actually_set_backlight(dev, pipe, 0);
 
 	if (INTEL_INFO(dev)->gen >= 4) {
 		uint32_t reg, tmp;
@@ -566,18 +580,23 @@ void intel_panel_disable_backlight(struct drm_device *dev)
 	spin_unlock_irqrestore(&dev_priv->backlight.lock, flags);
 }
 
-void intel_panel_enable_backlight(struct drm_device *dev,
-				  enum pipe pipe)
+void intel_panel_enable_backlight(struct intel_connector *connector)
 {
+	struct drm_device *dev = connector->base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
+	enum pipe pipe = intel_get_pipe_from_connector(connector);
 	enum transcoder cpu_transcoder =
 		intel_pipe_to_cpu_transcoder(dev_priv, pipe);
 	unsigned long flags;
 
+	if (pipe == INVALID_PIPE)
+		return;
+
 	spin_lock_irqsave(&dev_priv->backlight.lock, flags);
 
 	if (dev_priv->backlight.level == 0) {
-		dev_priv->backlight.level = intel_panel_get_max_backlight(dev);
+		dev_priv->backlight.level = intel_panel_get_max_backlight(dev,
+									  pipe);
 		if (dev_priv->backlight.device)
 			dev_priv->backlight.device->props.brightness =
 				dev_priv->backlight.level;
@@ -627,7 +646,8 @@ set_level:
 	 * registers are set.
 	 */
 	dev_priv->backlight.enabled = true;
-	intel_panel_actually_set_backlight(dev, dev_priv->backlight.level);
+	intel_panel_actually_set_backlight(dev, pipe,
+					   dev_priv->backlight.level);
 
 	spin_unlock_irqrestore(&dev_priv->backlight.lock, flags);
 }
@@ -650,7 +670,7 @@ static void intel_panel_init_backlight(struct drm_device *dev)
 
 	intel_panel_init_backlight_regs(dev);
 
-	dev_priv->backlight.level = intel_panel_get_backlight(dev);
+	dev_priv->backlight.level = intel_panel_get_backlight(dev, 0);
 	dev_priv->backlight.enabled = dev_priv->backlight.level != 0;
 }
 
@@ -679,16 +699,35 @@ intel_panel_detect(struct drm_device *dev)
 #if IS_ENABLED(CONFIG_BACKLIGHT_CLASS_DEVICE)
 static int intel_panel_update_status(struct backlight_device *bd)
 {
-	struct drm_device *dev = bl_get_data(bd);
-	intel_panel_set_backlight(dev, bd->props.brightness,
+	struct intel_connector *connector = bl_get_data(bd);
+	struct drm_device *dev = connector->base.dev;
+
+	mutex_lock(&dev->mode_config.mutex);
+	intel_panel_set_backlight(connector, bd->props.brightness,
 				  bd->props.max_brightness);
+	mutex_unlock(&dev->mode_config.mutex);
 	return 0;
 }
 
 static int intel_panel_get_brightness(struct backlight_device *bd)
 {
-	struct drm_device *dev = bl_get_data(bd);
-	return intel_panel_get_backlight(dev);
+	struct intel_connector *connector = bl_get_data(bd);
+	struct drm_device *dev = connector->base.dev;
+	enum pipe pipe;
+	int ret = 0;
+
+	mutex_lock(&dev->mode_config.mutex);
+	pipe = intel_get_pipe_from_connector(connector);
+	mutex_unlock(&dev->mode_config.mutex);
+	if (pipe == INVALID_PIPE) {
+		ret = 0;
+		goto out_unlock;
+	}
+
+	ret = intel_panel_get_backlight(connector->base.dev, pipe);
+out_unlock:
+	mutex_unlock(&dev->mode_config.mutex);
+	return ret;
 }
 
 static const struct backlight_ops intel_panel_bl_ops = {
@@ -708,12 +747,13 @@ int intel_panel_setup_backlight(struct drm_connector *connector)
 	if (WARN_ON(dev_priv->backlight.device))
 		return -ENODEV;
 
+	/* Just create a device for pipe 0 */
 	memset(&props, 0, sizeof(props));
 	props.type = BACKLIGHT_RAW;
 	props.brightness = dev_priv->backlight.level;
 
 	spin_lock_irqsave(&dev_priv->backlight.lock, flags);
-	props.max_brightness = intel_panel_get_max_backlight(dev);
+	props.max_brightness = intel_panel_get_max_backlight(dev, 0);
 	spin_unlock_irqrestore(&dev_priv->backlight.lock, flags);
 
 	if (props.max_brightness == 0) {
@@ -722,7 +762,8 @@ int intel_panel_setup_backlight(struct drm_connector *connector)
 	}
 	dev_priv->backlight.device =
 		backlight_device_register("intel_backlight",
-					  &connector->kdev, dev,
+					  &connector->kdev,
+					  to_intel_connector(connector),
 					  &intel_panel_bl_ops, &props);
 
 	if (IS_ERR(dev_priv->backlight.device)) {
-- 
1.8.3.1

[PATCH 2/2] drm/i915/vlv: use per-pipe backlight controls v2

[Jesse Barnes]

With the connector and pipe passed around, we can now set the backlight
on the right pipe on VLV/BYT.

v2: drop combination mode check for VLV (Jani)
    add save/restore code for VLV backlight regs (Jani)
    check for existing modulation freq when initializing backlight regs (Jani)

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
---
 drivers/gpu/drm/i915/i915_drv.h     |  3 ++
 drivers/gpu/drm/i915/i915_reg.h     | 15 +++++++++
 drivers/gpu/drm/i915/i915_suspend.c | 29 ++++++++++++++++
 drivers/gpu/drm/i915/intel_panel.c  | 67 ++++++++++++++++++++++++++++++-------
 4 files changed, 102 insertions(+), 12 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 53a555c..e7d211f 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -718,6 +718,9 @@ struct i915_suspend_saved_registers {
 	u32 saveBLC_HIST_CTL;
 	u32 saveBLC_PWM_CTL;
 	u32 saveBLC_PWM_CTL2;
+	u32 saveBLC_HIST_CTL_B;
+	u32 saveBLC_PWM_CTL_B;
+	u32 saveBLC_PWM_CTL2_B;
 	u32 saveBLC_CPU_PWM_CTL;
 	u32 saveBLC_CPU_PWM_CTL2;
 	u32 saveFPB0;
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 4be72b2..b64b1a6 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -2304,6 +2304,21 @@
 
 #define PFIT_AUTO_RATIOS (dev_priv->info->display_mmio_offset + 0x61238)
 
+#define _VLV_BLC_PWM_CTL2_A (dev_priv->info->display_mmio_offset + 0x61250)
+#define _VLV_BLC_PWM_CTL2_B (dev_priv->info->display_mmio_offset + 0x61350)
+#define VLV_BLC_PWM_CTL2(pipe) _PIPE(pipe, _VLV_BLC_PWM_CTL2_A, \
+				     _VLV_BLC_PWM_CTL2_B)
+
+#define _VLV_BLC_PWM_CTL_A (dev_priv->info->display_mmio_offset + 0x61254)
+#define _VLV_BLC_PWM_CTL_B (dev_priv->info->display_mmio_offset + 0x61354)
+#define VLV_BLC_PWM_CTL(pipe) _PIPE(pipe, _VLV_BLC_PWM_CTL_A, \
+				    _VLV_BLC_PWM_CTL_B)
+
+#define _VLV_BLC_HIST_CTL_A (dev_priv->info->display_mmio_offset + 0x61260)
+#define _VLV_BLC_HIST_CTL_B (dev_priv->info->display_mmio_offset + 0x61360)
+#define VLV_BLC_HIST_CTL(pipe) _PIPE(pipe, _VLV_BLC_HIST_CTL_A, \
+				     _VLV_BLC_HIST_CTL_B)
+
 /* Backlight control */
 #define BLC_PWM_CTL2	(dev_priv->info->display_mmio_offset + 0x61250) /* 965+ only */
 #define   BLM_PWM_ENABLE		(1 << 31)
diff --git a/drivers/gpu/drm/i915/i915_suspend.c b/drivers/gpu/drm/i915/i915_suspend.c
index 3538370..97ca8f1 100644
--- a/drivers/gpu/drm/i915/i915_suspend.c
+++ b/drivers/gpu/drm/i915/i915_suspend.c
@@ -214,6 +214,22 @@ static void i915_save_display(struct drm_device *dev)
 		dev_priv->regfile.saveBLC_CPU_PWM_CTL2 = I915_READ(BLC_PWM_CPU_CTL2);
 		if (HAS_PCH_IBX(dev) || HAS_PCH_CPT(dev))
 			dev_priv->regfile.saveLVDS = I915_READ(PCH_LVDS);
+	} else if (IS_VALLEYVIEW(dev)) {
+		dev_priv->regfile.savePP_CONTROL = I915_READ(PP_CONTROL);
+		dev_priv->regfile.savePFIT_PGM_RATIOS = I915_READ(PFIT_PGM_RATIOS);
+
+		dev_priv->regfile.saveBLC_PWM_CTL =
+			I915_READ(VLV_BLC_PWM_CTL(PIPE_A));
+		dev_priv->regfile.saveBLC_HIST_CTL =
+			I915_READ(VLV_BLC_HIST_CTL(PIPE_A));
+		dev_priv->regfile.saveBLC_PWM_CTL2 =
+			I915_READ(VLV_BLC_PWM_CTL2(PIPE_A));
+		dev_priv->regfile.saveBLC_PWM_CTL_B =
+			I915_READ(VLV_BLC_PWM_CTL(PIPE_B));
+		dev_priv->regfile.saveBLC_HIST_CTL_B =
+			I915_READ(VLV_BLC_HIST_CTL(PIPE_B));
+		dev_priv->regfile.saveBLC_PWM_CTL2_B =
+			I915_READ(VLV_BLC_PWM_CTL2(PIPE_B));
 	} else {
 		dev_priv->regfile.savePP_CONTROL = I915_READ(PP_CONTROL);
 		dev_priv->regfile.savePFIT_PGM_RATIOS = I915_READ(PFIT_PGM_RATIOS);
@@ -302,6 +318,19 @@ static void i915_restore_display(struct drm_device *dev)
 		I915_WRITE(PCH_PP_CONTROL, dev_priv->regfile.savePP_CONTROL);
 		I915_WRITE(RSTDBYCTL,
 			   dev_priv->regfile.saveMCHBAR_RENDER_STANDBY);
+	} else if (IS_VALLEYVIEW(dev)) {
+		I915_WRITE(VLV_BLC_PWM_CTL(PIPE_A),
+			   dev_priv->regfile.saveBLC_PWM_CTL);
+		I915_WRITE(VLV_BLC_HIST_CTL(PIPE_A),
+			   dev_priv->regfile.saveBLC_HIST_CTL);
+		I915_WRITE(VLV_BLC_PWM_CTL2(PIPE_A),
+			   dev_priv->regfile.saveBLC_PWM_CTL2);
+		I915_WRITE(VLV_BLC_PWM_CTL(PIPE_B),
+			   dev_priv->regfile.saveBLC_PWM_CTL);
+		I915_WRITE(VLV_BLC_HIST_CTL(PIPE_B),
+			   dev_priv->regfile.saveBLC_HIST_CTL);
+		I915_WRITE(VLV_BLC_PWM_CTL2(PIPE_B),
+			   dev_priv->regfile.saveBLC_PWM_CTL2);
 	} else {
 		I915_WRITE(PFIT_PGM_RATIOS, dev_priv->regfile.savePFIT_PGM_RATIOS);
 		I915_WRITE(BLC_PWM_CTL, dev_priv->regfile.saveBLC_PWM_CTL);
diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c
index 0026060..153c406 100644
--- a/drivers/gpu/drm/i915/intel_panel.c
+++ b/drivers/gpu/drm/i915/intel_panel.c
@@ -358,6 +358,21 @@ static u32 i915_read_blc_pwm_ctl(struct drm_device *dev, enum pipe pipe)
 			val = dev_priv->regfile.saveBLC_PWM_CTL2;
 			I915_WRITE(BLC_PWM_PCH_CTL2, val);
 		}
+	} else if (IS_VALLEYVIEW(dev)) {
+		val = I915_READ(VLV_BLC_PWM_CTL(pipe));
+		if (dev_priv->regfile.saveBLC_PWM_CTL == 0) {
+			dev_priv->regfile.saveBLC_PWM_CTL = val;
+			dev_priv->regfile.saveBLC_PWM_CTL2 =
+				I915_READ(VLV_BLC_PWM_CTL2(pipe));
+		} else if (val == 0) {
+			val = dev_priv->regfile.saveBLC_PWM_CTL;
+			I915_WRITE(VLV_BLC_PWM_CTL(pipe), val);
+			I915_WRITE(VLV_BLC_PWM_CTL2(pipe),
+				   dev_priv->regfile.saveBLC_PWM_CTL2);
+		}
+
+		if (!val)
+			val = 0x0f42ffff;
 	} else {
 		val = I915_READ(BLC_PWM_CTL);
 		if (dev_priv->regfile.saveBLC_PWM_CTL == 0) {
@@ -372,9 +387,6 @@ static u32 i915_read_blc_pwm_ctl(struct drm_device *dev, enum pipe pipe)
 				I915_WRITE(BLC_PWM_CTL2,
 					   dev_priv->regfile.saveBLC_PWM_CTL2);
 		}
-
-		if (IS_VALLEYVIEW(dev) && !val)
-			val = 0x0f42ffff;
 	}
 
 	return val;
@@ -435,13 +447,19 @@ static u32 intel_panel_get_backlight(struct drm_device *dev,
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	u32 val;
 	unsigned long flags;
+	int reg;
 
 	spin_lock_irqsave(&dev_priv->backlight.lock, flags);
 
 	if (HAS_PCH_SPLIT(dev)) {
 		val = I915_READ(BLC_PWM_CPU_CTL) & BACKLIGHT_DUTY_CYCLE_MASK;
 	} else {
-		val = I915_READ(BLC_PWM_CTL) & BACKLIGHT_DUTY_CYCLE_MASK;
+		if (IS_VALLEYVIEW(dev))
+			reg = VLV_BLC_PWM_CTL(pipe);
+		else
+			reg = BLC_PWM_CTL;
+
+		val = I915_READ(reg) & BACKLIGHT_DUTY_CYCLE_MASK;
 		if (INTEL_INFO(dev)->gen < 4)
 			val >>= 1;
 
@@ -473,6 +491,7 @@ static void intel_panel_actually_set_backlight(struct drm_device *dev,
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	u32 tmp;
+	int reg;
 
 	DRM_DEBUG_DRIVER("set backlight PWM = %d\n", level);
 	level = intel_panel_compute_brightness(dev, pipe, level);
@@ -493,11 +512,16 @@ static void intel_panel_actually_set_backlight(struct drm_device *dev,
 		pci_write_config_byte(dev->pdev, PCI_LBPC, lbpc);
 	}
 
-	tmp = I915_READ(BLC_PWM_CTL);
+	if (IS_VALLEYVIEW(dev))
+		reg = VLV_BLC_PWM_CTL(pipe);
+	else
+		reg = BLC_PWM_CTL;
+
+	tmp = I915_READ(reg);
 	if (INTEL_INFO(dev)->gen < 4)
 		level <<= 1;
 	tmp &= ~BACKLIGHT_DUTY_CYCLE_MASK;
-	I915_WRITE(BLC_PWM_CTL, tmp | level);
+	I915_WRITE(reg, tmp | level);
 }
 
 /* set backlight brightness to level in range [0..max] */
@@ -566,7 +590,12 @@ void intel_panel_disable_backlight(struct intel_connector *connector)
 	if (INTEL_INFO(dev)->gen >= 4) {
 		uint32_t reg, tmp;
 
-		reg = HAS_PCH_SPLIT(dev) ? BLC_PWM_CPU_CTL2 : BLC_PWM_CTL2;
+		if (HAS_PCH_SPLIT(dev))
+			reg = BLC_PWM_CPU_CTL2;
+		else if (IS_VALLEYVIEW(dev))
+			reg = VLV_BLC_PWM_CTL2(pipe);
+		else
+			reg = BLC_PWM_CTL2;
 
 		I915_WRITE(reg, I915_READ(reg) & ~BLM_PWM_ENABLE);
 
@@ -605,8 +634,12 @@ void intel_panel_enable_backlight(struct intel_connector *connector)
 	if (INTEL_INFO(dev)->gen >= 4) {
 		uint32_t reg, tmp;
 
-		reg = HAS_PCH_SPLIT(dev) ? BLC_PWM_CPU_CTL2 : BLC_PWM_CTL2;
-
+		if (HAS_PCH_SPLIT(dev))
+			reg = BLC_PWM_CPU_CTL2;
+		else if (IS_VALLEYVIEW(dev))
+			reg = VLV_BLC_PWM_CTL2(pipe);
+		else
+			reg = BLC_PWM_CTL2;
 
 		tmp = I915_READ(reg);
 
@@ -658,9 +691,19 @@ static void intel_panel_init_backlight_regs(struct drm_device *dev)
 	struct drm_i915_private *dev_priv = dev->dev_private;
 
 	if (IS_VALLEYVIEW(dev)) {
-		u32 cur_val = I915_READ(BLC_PWM_CTL) &
-			BACKLIGHT_DUTY_CYCLE_MASK;
-		I915_WRITE(BLC_PWM_CTL, (0xf42 << 16) | cur_val);
+		enum pipe pipe;
+
+		for_each_pipe(pipe) {
+			u32 cur_val = I915_READ(VLV_BLC_PWM_CTL(pipe));
+
+			/* Skip if the modulation freq is already set */
+			if (cur_val & ~BACKLIGHT_DUTY_CYCLE_MASK)
+				continue;
+
+			cur_val &= BACKLIGHT_DUTY_CYCLE_MASK;
+			I915_WRITE(VLV_BLC_PWM_CTL(pipe), (0xf42 << 16) |
+				   cur_val);
+		}
 	}
 }
 
-- 
1.8.3.1

Re: [PATCH 1/2] drm/i915: make backlight functions take a connector v3

[Daniel Vetter]

On Fri, Oct 11, 2013 at 11:31:53AM -0700, Jesse Barnes wrote:

[snip]

>  static int intel_panel_get_brightness(struct backlight_device *bd)
>  {
> -	struct drm_device *dev = bl_get_data(bd);
> -	return intel_panel_get_backlight(dev);
> +	struct intel_connector *connector = bl_get_data(bd);
> +	struct drm_device *dev = connector->base.dev;
> +	enum pipe pipe;
> +	int ret = 0;
> +
> +	mutex_lock(&dev->mode_config.mutex);
> +	pipe = intel_get_pipe_from_connector(connector);
> +	mutex_unlock(&dev->mode_config.mutex);
> +	if (pipe == INVALID_PIPE) {
> +		ret = 0;
> +		goto out_unlock;
> +	}
> +
> +	ret = intel_panel_get_backlight(connector->base.dev, pipe);
> +out_unlock:
> +	mutex_unlock(&dev->mode_config.mutex);

I see mutex_unlock(&dev->mode_config.mutex) twice here. I think you've
just volunteered yourselve for some testcases ;-)

Ideas:
- Make sure all lvds/edp connectors are enabled and bash on all backlight
  interfaces (with igt_fork it's easy to do that concurrently).
- Race the above with output changes: dpms on/off and changing the crtc
  around.
- Race the above with system suspend for bonus points (can be completely
  stitched together from igt helpers).

Cheers, Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch

Re: [PATCH 1/2] drm/i915: make backlight functions take a connector v3

[Jesse Barnes]

On Fri, 11 Oct 2013 23:31:10 +0200
Daniel Vetter <daniel@ffwll.ch> wrote:

> On Fri, Oct 11, 2013 at 11:31:53AM -0700, Jesse Barnes wrote:
> 
> [snip]
> 
> >  static int intel_panel_get_brightness(struct backlight_device *bd)
> >  {
> > -	struct drm_device *dev = bl_get_data(bd);
> > -	return intel_panel_get_backlight(dev);
> > +	struct intel_connector *connector = bl_get_data(bd);
> > +	struct drm_device *dev = connector->base.dev;
> > +	enum pipe pipe;
> > +	int ret = 0;
> > +
> > +	mutex_lock(&dev->mode_config.mutex);
> > +	pipe = intel_get_pipe_from_connector(connector);
> > +	mutex_unlock(&dev->mode_config.mutex);
> > +	if (pipe == INVALID_PIPE) {
> > +		ret = 0;
> > +		goto out_unlock;
> > +	}
> > +
> > +	ret = intel_panel_get_backlight(connector->base.dev, pipe);
> > +out_unlock:
> > +	mutex_unlock(&dev->mode_config.mutex);
> 
> I see mutex_unlock(&dev->mode_config.mutex) twice here. I think you've
> just volunteered yourselve for some testcases ;-)
> 
> Ideas:
> - Make sure all lvds/edp connectors are enabled and bash on all backlight
>   interfaces (with igt_fork it's easy to do that concurrently).
> - Race the above with output changes: dpms on/off and changing the crtc
>   around.
> - Race the above with system suspend for bonus points (can be completely
>   stitched together from igt helpers).

Sorry can't volunteer for that now, but those sound like good tests to
write.

I'll fix up the patch, we don't need to make double sure the lock is
unlocked do we? and test locally and re-send.

-- 
Jesse Barnes, Intel Open Source Technology Center

[PATCH] drm/i915: make backlight functions take a connector v4

[Jesse Barnes]

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)

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
---
 drivers/gpu/drm/i915/i915_drv.h       |  1 +
 drivers/gpu/drm/i915/intel_display.c  | 12 +++++
 drivers/gpu/drm/i915/intel_dp.c       |  5 +-
 drivers/gpu/drm/i915/intel_drv.h      |  8 +--
 drivers/gpu/drm/i915/intel_lvds.c     |  9 ++--
 drivers/gpu/drm/i915/intel_opregion.c | 38 ++++++++++++++-
 drivers/gpu/drm/i915/intel_panel.c    | 92 +++++++++++++++++++++++++----------
 7 files changed, 128 insertions(+), 37 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index ed8653f..53a555c 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/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,
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 0ba0af4..53c4ea8 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -9729,6 +9729,18 @@ 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)
 {
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 0ed7717..6391c7d 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -1257,7 +1257,6 @@ 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;
 
@@ -1280,7 +1279,7 @@ 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)
@@ -1293,7 +1292,7 @@ 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);
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 922c5d7..476d98b 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -619,6 +619,7 @@ 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,
@@ -767,10 +768,11 @@ 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);
 
diff --git a/drivers/gpu/drm/i915/intel_lvds.c b/drivers/gpu/drm/i915/intel_lvds.c
index ae0c843..30933ab 100644
--- a/drivers/gpu/drm/i915/intel_lvds.c
+++ b/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))
diff --git a/drivers/gpu/drm/i915/intel_opregion.c b/drivers/gpu/drm/i915/intel_opregion.c
index 2acf5ca..0afaa72 100644
--- a/drivers/gpu/drm/i915/intel_opregion.c
+++ b/drivers/gpu/drm/i915/intel_opregion.c
@@ -395,6 +395,12 @@ static u32 asle_set_backlight(struct drm_device *dev, u32 bclp)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	struct opregion_asle __iomem *asle = dev_priv->opregion.asle;
+	struct drm_crtc *crtc = dev_priv->pipe_to_crtc_mapping[0];
+	struct drm_encoder *encoder;
+	struct drm_connector *connector;
+	struct intel_connector *intel_connector = NULL;
+	bool found = false;
+	int ret = 0;
 
 	DRM_DEBUG_DRIVER("bclp = 0x%08x\n", bclp);
 
@@ -405,10 +411,38 @@ static u32 asle_set_backlight(struct drm_device *dev, u32 bclp)
 	if (bclp > 255)
 		return ASLC_BACKLIGHT_FAILED;
 
-	intel_panel_set_backlight(dev, bclp, 255);
+	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_unlock;
+	}
+
+	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_unlock;
+	}
+
+	intel_panel_set_backlight(intel_connector, bclp, 255);
 	iowrite32(DIV_ROUND_UP(bclp * 100, 255) | ASLE_CBLV_VALID, &asle->cblv);
 
-	return 0;
+out_unlock:
+	mutex_unlock(&dev->mode_config.mutex);
+	return ret;
 }
 
 static u32 asle_set_als_illum(struct drm_device *dev, u32 alsi)
diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c
index 5468416..86d1ee9 100644
--- a/drivers/gpu/drm/i915/intel_panel.c
+++ b/drivers/gpu/drm/i915/intel_panel.c
@@ -341,7 +341,7 @@ static int is_backlight_combination_mode(struct drm_device *dev)
 /* XXX: query mode clock or hardware clock and program max PWM appropriately
  * when it's 0.
  */
-static u32 i915_read_blc_pwm_ctl(struct drm_device *dev)
+static u32 i915_read_blc_pwm_ctl(struct drm_device *dev, enum pipe pipe)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	u32 val;
@@ -380,11 +380,12 @@ static u32 i915_read_blc_pwm_ctl(struct drm_device *dev)
 	return val;
 }
 
-static u32 intel_panel_get_max_backlight(struct drm_device *dev)
+static u32 intel_panel_get_max_backlight(struct drm_device *dev,
+					 enum pipe pipe)
 {
 	u32 max;
 
-	max = i915_read_blc_pwm_ctl(dev);
+	max = i915_read_blc_pwm_ctl(dev, pipe);
 
 	if (HAS_PCH_SPLIT(dev)) {
 		max >>= 16;
@@ -410,7 +411,8 @@ MODULE_PARM_DESC(invert_brightness, "Invert backlight brightness "
 	"to dri-devel@lists.freedesktop.org, if your machine needs it. "
 	"It will then be included in an upcoming module version.");
 module_param_named(invert_brightness, i915_panel_invert_brightness, int, 0600);
-static u32 intel_panel_compute_brightness(struct drm_device *dev, u32 val)
+static u32 intel_panel_compute_brightness(struct drm_device *dev,
+					  enum pipe pipe, u32 val)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 
@@ -419,7 +421,7 @@ static u32 intel_panel_compute_brightness(struct drm_device *dev, u32 val)
 
 	if (i915_panel_invert_brightness > 0 ||
 	    dev_priv->quirks & QUIRK_INVERT_BRIGHTNESS) {
-		u32 max = intel_panel_get_max_backlight(dev);
+		u32 max = intel_panel_get_max_backlight(dev, pipe);
 		if (max)
 			return max - val;
 	}
@@ -427,7 +429,8 @@ static u32 intel_panel_compute_brightness(struct drm_device *dev, u32 val)
 	return val;
 }
 
-static u32 intel_panel_get_backlight(struct drm_device *dev)
+static u32 intel_panel_get_backlight(struct drm_device *dev,
+				     enum pipe pipe)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	u32 val;
@@ -450,7 +453,7 @@ static u32 intel_panel_get_backlight(struct drm_device *dev)
 		}
 	}
 
-	val = intel_panel_compute_brightness(dev, val);
+	val = intel_panel_compute_brightness(dev, pipe, val);
 
 	spin_unlock_irqrestore(&dev_priv->backlight.lock, flags);
 
@@ -466,19 +469,19 @@ static void intel_pch_panel_set_backlight(struct drm_device *dev, u32 level)
 }
 
 static void intel_panel_actually_set_backlight(struct drm_device *dev,
-					       u32 level)
+					       enum pipe pipe, u32 level)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	u32 tmp;
 
 	DRM_DEBUG_DRIVER("set backlight PWM = %d\n", level);
-	level = intel_panel_compute_brightness(dev, level);
+	level = intel_panel_compute_brightness(dev, pipe, level);
 
 	if (HAS_PCH_SPLIT(dev))
 		return intel_pch_panel_set_backlight(dev, level);
 
 	if (is_backlight_combination_mode(dev)) {
-		u32 max = intel_panel_get_max_backlight(dev);
+		u32 max = intel_panel_get_max_backlight(dev, pipe);
 		u8 lbpc;
 
 		/* we're screwed, but keep behaviour backwards compatible */
@@ -498,15 +501,21 @@ static void intel_panel_actually_set_backlight(struct drm_device *dev,
 }
 
 /* set backlight brightness to level in range [0..max] */
-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)
 {
+	struct drm_device *dev = connector->base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
+	enum pipe pipe = intel_get_pipe_from_connector(connector);
 	u32 freq;
 	unsigned long flags;
 
+	if (pipe == INVALID_PIPE)
+		return;
+
 	spin_lock_irqsave(&dev_priv->backlight.lock, flags);
 
-	freq = intel_panel_get_max_backlight(dev);
+	freq = intel_panel_get_max_backlight(dev, pipe);
 	if (!freq) {
 		/* we are screwed, bail out */
 		goto out;
@@ -523,16 +532,21 @@ void intel_panel_set_backlight(struct drm_device *dev, u32 level, u32 max)
 		dev_priv->backlight.device->props.brightness = level;
 
 	if (dev_priv->backlight.enabled)
-		intel_panel_actually_set_backlight(dev, level);
+		intel_panel_actually_set_backlight(dev, pipe, level);
 out:
 	spin_unlock_irqrestore(&dev_priv->backlight.lock, flags);
 }
 
-void intel_panel_disable_backlight(struct drm_device *dev)
+void intel_panel_disable_backlight(struct intel_connector *connector)
 {
+	struct drm_device *dev = connector->base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
+	enum pipe pipe = intel_get_pipe_from_connector(connector);
 	unsigned long flags;
 
+	if (pipe == INVALID_PIPE)
+		return;
+
 	/*
 	 * Do not disable backlight on the vgaswitcheroo path. When switching
 	 * away from i915, the other client may depend on i915 to handle the
@@ -547,7 +561,7 @@ void intel_panel_disable_backlight(struct drm_device *dev)
 	spin_lock_irqsave(&dev_priv->backlight.lock, flags);
 
 	dev_priv->backlight.enabled = false;
-	intel_panel_actually_set_backlight(dev, 0);
+	intel_panel_actually_set_backlight(dev, pipe, 0);
 
 	if (INTEL_INFO(dev)->gen >= 4) {
 		uint32_t reg, tmp;
@@ -566,18 +580,23 @@ void intel_panel_disable_backlight(struct drm_device *dev)
 	spin_unlock_irqrestore(&dev_priv->backlight.lock, flags);
 }
 
-void intel_panel_enable_backlight(struct drm_device *dev,
-				  enum pipe pipe)
+void intel_panel_enable_backlight(struct intel_connector *connector)
 {
+	struct drm_device *dev = connector->base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
+	enum pipe pipe = intel_get_pipe_from_connector(connector);
 	enum transcoder cpu_transcoder =
 		intel_pipe_to_cpu_transcoder(dev_priv, pipe);
 	unsigned long flags;
 
+	if (pipe == INVALID_PIPE)
+		return;
+
 	spin_lock_irqsave(&dev_priv->backlight.lock, flags);
 
 	if (dev_priv->backlight.level == 0) {
-		dev_priv->backlight.level = intel_panel_get_max_backlight(dev);
+		dev_priv->backlight.level = intel_panel_get_max_backlight(dev,
+									  pipe);
 		if (dev_priv->backlight.device)
 			dev_priv->backlight.device->props.brightness =
 				dev_priv->backlight.level;
@@ -627,7 +646,8 @@ set_level:
 	 * registers are set.
 	 */
 	dev_priv->backlight.enabled = true;
-	intel_panel_actually_set_backlight(dev, dev_priv->backlight.level);
+	intel_panel_actually_set_backlight(dev, pipe,
+					   dev_priv->backlight.level);
 
 	spin_unlock_irqrestore(&dev_priv->backlight.lock, flags);
 }
@@ -650,7 +670,7 @@ static void intel_panel_init_backlight(struct drm_device *dev)
 
 	intel_panel_init_backlight_regs(dev);
 
-	dev_priv->backlight.level = intel_panel_get_backlight(dev);
+	dev_priv->backlight.level = intel_panel_get_backlight(dev, 0);
 	dev_priv->backlight.enabled = dev_priv->backlight.level != 0;
 }
 
@@ -679,16 +699,34 @@ intel_panel_detect(struct drm_device *dev)
 #if IS_ENABLED(CONFIG_BACKLIGHT_CLASS_DEVICE)
 static int intel_panel_update_status(struct backlight_device *bd)
 {
-	struct drm_device *dev = bl_get_data(bd);
-	intel_panel_set_backlight(dev, bd->props.brightness,
+	struct intel_connector *connector = bl_get_data(bd);
+	struct drm_device *dev = connector->base.dev;
+
+	mutex_lock(&dev->mode_config.mutex);
+	intel_panel_set_backlight(connector, bd->props.brightness,
 				  bd->props.max_brightness);
+	mutex_unlock(&dev->mode_config.mutex);
 	return 0;
 }
 
 static int intel_panel_get_brightness(struct backlight_device *bd)
 {
-	struct drm_device *dev = bl_get_data(bd);
-	return intel_panel_get_backlight(dev);
+	struct intel_connector *connector = bl_get_data(bd);
+	struct drm_device *dev = connector->base.dev;
+	enum pipe pipe;
+	int ret = 0;
+
+	mutex_lock(&dev->mode_config.mutex);
+	pipe = intel_get_pipe_from_connector(connector);
+	mutex_unlock(&dev->mode_config.mutex);
+	if (pipe == INVALID_PIPE) {
+		ret = 0;
+		goto out;
+	}
+
+	ret = intel_panel_get_backlight(connector->base.dev, pipe);
+out:
+	return ret;
 }
 
 static const struct backlight_ops intel_panel_bl_ops = {
@@ -708,12 +746,13 @@ int intel_panel_setup_backlight(struct drm_connector *connector)
 	if (WARN_ON(dev_priv->backlight.device))
 		return -ENODEV;
 
+	/* Just create a device for pipe 0 */
 	memset(&props, 0, sizeof(props));
 	props.type = BACKLIGHT_RAW;
 	props.brightness = dev_priv->backlight.level;
 
 	spin_lock_irqsave(&dev_priv->backlight.lock, flags);
-	props.max_brightness = intel_panel_get_max_backlight(dev);
+	props.max_brightness = intel_panel_get_max_backlight(dev, 0);
 	spin_unlock_irqrestore(&dev_priv->backlight.lock, flags);
 
 	if (props.max_brightness == 0) {
@@ -722,7 +761,8 @@ int intel_panel_setup_backlight(struct drm_connector *connector)
 	}
 	dev_priv->backlight.device =
 		backlight_device_register("intel_backlight",
-					  &connector->kdev, dev,
+					  &connector->kdev,
+					  to_intel_connector(connector),
 					  &intel_panel_bl_ops, &props);
 
 	if (IS_ERR(dev_priv->backlight.device)) {
-- 
1.8.3.1

Re: [PATCH] drm/i915: make backlight functions take a connector v4

[Jesse Barnes]

On Fri, 11 Oct 2013 14:46:36 -0700
Jesse Barnes <jbarnes@virtuousgeek.org> wrote:

> 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)

Ok ok you caught me.  I didn't test v3...  I did test this version but
w/o lockdep and apparently w/o any ASLE events or I would have seen the
sleeping while atomic messages.

Guess we'll have to factor out the ASLE callback into a work queue (I
don't *think* the BIOS will care, we'll have to see).

-- 
Jesse Barnes, Intel Open Source Technology Center

Re: [PATCH 1/2] drm/i915: make backlight functions take a connector v3

[Jesse Barnes]

On Fri, 11 Oct 2013 14:34:35 -0700
Jesse Barnes <jbarnes@virtuousgeek.org> wrote:

> > Ideas:
> > - Make sure all lvds/edp connectors are enabled and bash on all backlight
> >   interfaces (with igt_fork it's easy to do that concurrently).
> > - Race the above with output changes: dpms on/off and changing the crtc
> >   around.
> > - Race the above with system suspend for bonus points (can be completely
> >   stitched together from igt helpers).  
> 
> Sorry can't volunteer for that now, but those sound like good tests to
> write.

To clarify per our discussion on IRC.  I'll try to make some time next
week to add some tests for this.  We'll need them for the further
intel_panel.c work (getting rid of all the bogus save/restore of the
bits sprinkled about now that we don't do display reset).

But I don't want this fix (once I fix the locking) blocked on
those tests, since they'll probably take me a few days and people are
already using the original version, which is missing the locks for the
backlight class and ASLE call sites.

Thanks,
-- 
Jesse Barnes, Intel Open Source Technology Center

Re: [PATCH 1/2] drm/i915: make backlight functions take a connector v3

[Daniel Vetter]

On Sat, Oct 12, 2013 at 1:19 AM, Jesse Barnes <jbarnes@virtuousgeek.org> wrote:
> On Fri, 11 Oct 2013 14:34:35 -0700
> Jesse Barnes <jbarnes@virtuousgeek.org> wrote:
>
>> > Ideas:
>> > - Make sure all lvds/edp connectors are enabled and bash on all backlight
>> >   interfaces (with igt_fork it's easy to do that concurrently).
>> > - Race the above with output changes: dpms on/off and changing the crtc
>> >   around.
>> > - Race the above with system suspend for bonus points (can be completely
>> >   stitched together from igt helpers).
>>
>> Sorry can't volunteer for that now, but those sound like good tests to
>> write.
>
> To clarify per our discussion on IRC.  I'll try to make some time next
> week to add some tests for this.  We'll need them for the further
> intel_panel.c work (getting rid of all the bogus save/restore of the
> bits sprinkled about now that we don't do display reset).
>
> But I don't want this fix (once I fix the locking) blocked on
> those tests, since they'll probably take me a few days and people are
> already using the original version, which is missing the locks for the
> backlight class and ASLE call sites.

Yeah, I'm happy with this plan. Unfortunately it looks like this is
another hornet's nest. So having a bit (and even if it's just a tiny
little bit) of automated sanity checking and stress-testing of the
locking should help to avoid the "two steps left, one back" dance we
so often fall into. So if you have ideas for more effective tests than
my quick list just do those, after all you'll know better how to blow
this up after a few days of banging your head against the problem than
me ;-)
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch

Re: [PATCH 1/2] drm/i915: make backlight functions take a connector v3

[Daniel Vetter]

On Sat, Oct 12, 2013 at 1:55 AM, Daniel Vetter <daniel@ffwll.ch> wrote:
> On Sat, Oct 12, 2013 at 1:19 AM, Jesse Barnes <jbarnes@virtuousgeek.org> wrote:
>> On Fri, 11 Oct 2013 14:34:35 -0700
>> Jesse Barnes <jbarnes@virtuousgeek.org> wrote:
>>
>>> > Ideas:
>>> > - Make sure all lvds/edp connectors are enabled and bash on all backlight
>>> >   interfaces (with igt_fork it's easy to do that concurrently).
>>> > - Race the above with output changes: dpms on/off and changing the crtc
>>> >   around.
>>> > - Race the above with system suspend for bonus points (can be completely
>>> >   stitched together from igt helpers).
>>>
>>> Sorry can't volunteer for that now, but those sound like good tests to
>>> write.
>>
>> To clarify per our discussion on IRC.  I'll try to make some time next
>> week to add some tests for this.  We'll need them for the further
>> intel_panel.c work (getting rid of all the bogus save/restore of the
>> bits sprinkled about now that we don't do display reset).
>>
>> But I don't want this fix (once I fix the locking) blocked on
>> those tests, since they'll probably take me a few days and people are
>> already using the original version, which is missing the locks for the
>> backlight class and ASLE call sites.
>
> Yeah, I'm happy with this plan. Unfortunately it looks like this is
> another hornet's nest. So having a bit (and even if it's just a tiny
> little bit) of automated sanity checking and stress-testing of the
> locking should help to avoid the "two steps left, one back" dance we
> so often fall into. So if you have ideas for more effective tests than
> my quick list just do those, after all you'll know better how to blow
> this up after a few days of banging your head against the problem than
> me ;-)

Aside: For patch that fix existing bugs where we can directly
reproduce the issue in upstream with a test (e.g. tiling after resume
broken) I prefer to first commit the testcase to igt and then wait 2-3
days. If the testcase is ready with the patch this can nicely overlap
with the patch review and allows us to check the robustness of the
testcase: If QA doesn't file a new bug, something isn't quite working
(either in the test or with QA), and we need to figure out what's
wrong.

At least for gem issues this has been SOP.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch

intel-drm-nightly broken on 835GM

[Thomas Richter]

Hi Daniel,

finally had access again to the Fujitsu laptop with the 835GM chipset. 
This time, I checked up the nightly-built branch based on the 3.12.rc4 
kernel. Similar to the 3.11 kernel, I get a blank screen during login, 
i.e. gdm does not render its graphics. The boot console, even after 
loading the i915 module, does appear, is however vertically misaligned. 
The first line(s) of the console do not show.

When booting with an external monitor connected, the internal DVO locks 
up, and the signal on the external monitor is flickering left and right, 
as already described. gdm does not render on the internal panel, and the 
external panel remains black.

Thus, 3.12rc4 drm-nightly works (unfortunately) as bad as the 3.11 and 
is not usable.

Greetings,
	Thomas

Re: [PATCH 1/2] drm/i915: make backlight functions take a connector v3

[Daniel Vetter]

On Sat, Oct 12, 2013 at 1:19 AM, Jesse Barnes <jbarnes@virtuousgeek.org> wrote:
> But I don't want this fix (once I fix the locking) blocked on
> those tests, since they'll probably take me a few days and people are
> already using the original version, which is missing the locks for the
> backlight class and ASLE call sites.

btw for fixing the asle mutex_lock-in-irq-context issue we might want
to simply use a trylock - Iirc the opregion spec explicitly allows us
to abort the request as "driver busy with modeset ops". Imo both
approaches of either delaying the request to a workqueue or using the
asle return value feel equally risky wrt funky bioses doing stupid
things. In both cases we need to get real-world testing, but using the
trylock + abort is simpler in our own code ;-)
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch

[PATCH] drm/i915: make backlight functions take a connector v5

[Jesse Barnes]

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)

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
---
 drivers/gpu/drm/i915/i915_drv.h       |  2 +
 drivers/gpu/drm/i915/intel_display.c  | 12 +++++
 drivers/gpu/drm/i915/intel_dp.c       |  5 +-
 drivers/gpu/drm/i915/intel_drv.h      |  8 +--
 drivers/gpu/drm/i915/intel_lvds.c     |  9 ++--
 drivers/gpu/drm/i915/intel_opregion.c | 67 +++++++++++++++++++++----
 drivers/gpu/drm/i915/intel_panel.c    | 92 +++++++++++++++++++++++++----------
 7 files changed, 151 insertions(+), 44 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index ed8653f..82eb027 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/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,
@@ -231,6 +232,7 @@ struct intel_opregion {
 	struct opregion_asle __iomem *asle;
 	void __iomem *vbt;
 	u32 __iomem *lid_state;
+	struct work_struct asle_work;
 };
 #define OPREGION_SIZE            (8*1024)
 
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 0ba0af4..53c4ea8 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -9729,6 +9729,18 @@ 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)
 {
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 0ed7717..6391c7d 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -1257,7 +1257,6 @@ 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;
 
@@ -1280,7 +1279,7 @@ 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)
@@ -1293,7 +1292,7 @@ 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);
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 922c5d7..476d98b 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -619,6 +619,7 @@ 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,
@@ -767,10 +768,11 @@ 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);
 
diff --git a/drivers/gpu/drm/i915/intel_lvds.c b/drivers/gpu/drm/i915/intel_lvds.c
index ae0c843..30933ab 100644
--- a/drivers/gpu/drm/i915/intel_lvds.c
+++ b/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))
diff --git a/drivers/gpu/drm/i915/intel_opregion.c b/drivers/gpu/drm/i915/intel_opregion.c
index 2acf5ca..85bc3b1 100644
--- a/drivers/gpu/drm/i915/intel_opregion.c
+++ b/drivers/gpu/drm/i915/intel_opregion.c
@@ -391,24 +391,71 @@ int intel_opregion_notify_adapter(struct drm_device *dev, pci_power_t state)
 	return -EINVAL;
 }
 
-static u32 asle_set_backlight(struct drm_device *dev, u32 bclp)
+static void asle_backlight_work(struct work_struct *work)
 {
-	struct drm_i915_private *dev_priv = dev->dev_private;
+	struct intel_opregion *opregion = container_of(work,
+						       struct intel_opregion,
+						       asle_work);
+	struct drm_i915_private *dev_priv = container_of(opregion,
+							 struct drm_i915_private,
+							 opregion);
+	struct drm_device *dev = dev_priv->dev;
+	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 bclp, ret = 0;
+	bool found = false;
+
+	bclp = ioread32(&asle->bclp);
 
 	DRM_DEBUG_DRIVER("bclp = 0x%08x\n", bclp);
 
-	if (!(bclp & ASLE_BCLP_VALID))
-		return ASLC_BACKLIGHT_FAILED;
+	if (!(bclp & ASLE_BCLP_VALID)) {
+		ret = ASLC_BACKLIGHT_FAILED;
+		goto out;
+	}
 
 	bclp &= ASLE_BCLP_MSK;
-	if (bclp > 255)
-		return ASLC_BACKLIGHT_FAILED;
+	if (bclp > 255) {
+		ret = ASLC_BACKLIGHT_FAILED;
+		goto out;
+	}
 
-	intel_panel_set_backlight(dev, bclp, 255);
+	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_unlock;
+	}
+
+	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_unlock;
+	}
+
+	intel_panel_set_backlight(intel_connector, bclp, 255);
 	iowrite32(DIV_ROUND_UP(bclp * 100, 255) | ASLE_CBLV_VALID, &asle->cblv);
 
-	return 0;
+out_unlock:
+	mutex_unlock(&dev->mode_config.mutex);
+out:
+	iowrite32(ret, &asle->aslc);
 }
 
 static u32 asle_set_als_illum(struct drm_device *dev, u32 alsi)
@@ -505,7 +552,7 @@ void intel_opregion_asle_intr(struct drm_device *dev)
 		aslc_stat |= asle_set_als_illum(dev, ioread32(&asle->alsi));
 
 	if (aslc_req & ASLC_SET_BACKLIGHT)
-		aslc_stat |= asle_set_backlight(dev, ioread32(&asle->bclp));
+		schedule_work(&dev_priv->opregion.asle_work);
 
 	if (aslc_req & ASLC_SET_PFIT)
 		aslc_stat |= asle_set_pfit(dev, ioread32(&asle->pfit));
@@ -825,6 +872,8 @@ int intel_opregion_setup(struct drm_device *dev)
 		return -ENOTSUPP;
 	}
 
+	INIT_WORK(&opregion->asle_work, asle_backlight_work);
+
 	base = acpi_os_ioremap(asls, OPREGION_SIZE);
 	if (!base)
 		return -ENOMEM;
diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c
index 5468416..86d1ee9 100644
--- a/drivers/gpu/drm/i915/intel_panel.c
+++ b/drivers/gpu/drm/i915/intel_panel.c
@@ -341,7 +341,7 @@ static int is_backlight_combination_mode(struct drm_device *dev)
 /* XXX: query mode clock or hardware clock and program max PWM appropriately
  * when it's 0.
  */
-static u32 i915_read_blc_pwm_ctl(struct drm_device *dev)
+static u32 i915_read_blc_pwm_ctl(struct drm_device *dev, enum pipe pipe)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	u32 val;
@@ -380,11 +380,12 @@ static u32 i915_read_blc_pwm_ctl(struct drm_device *dev)
 	return val;
 }
 
-static u32 intel_panel_get_max_backlight(struct drm_device *dev)
+static u32 intel_panel_get_max_backlight(struct drm_device *dev,
+					 enum pipe pipe)
 {
 	u32 max;
 
-	max = i915_read_blc_pwm_ctl(dev);
+	max = i915_read_blc_pwm_ctl(dev, pipe);
 
 	if (HAS_PCH_SPLIT(dev)) {
 		max >>= 16;
@@ -410,7 +411,8 @@ MODULE_PARM_DESC(invert_brightness, "Invert backlight brightness "
 	"to dri-devel@lists.freedesktop.org, if your machine needs it. "
 	"It will then be included in an upcoming module version.");
 module_param_named(invert_brightness, i915_panel_invert_brightness, int, 0600);
-static u32 intel_panel_compute_brightness(struct drm_device *dev, u32 val)
+static u32 intel_panel_compute_brightness(struct drm_device *dev,
+					  enum pipe pipe, u32 val)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 
@@ -419,7 +421,7 @@ static u32 intel_panel_compute_brightness(struct drm_device *dev, u32 val)
 
 	if (i915_panel_invert_brightness > 0 ||
 	    dev_priv->quirks & QUIRK_INVERT_BRIGHTNESS) {
-		u32 max = intel_panel_get_max_backlight(dev);
+		u32 max = intel_panel_get_max_backlight(dev, pipe);
 		if (max)
 			return max - val;
 	}
@@ -427,7 +429,8 @@ static u32 intel_panel_compute_brightness(struct drm_device *dev, u32 val)
 	return val;
 }
 
-static u32 intel_panel_get_backlight(struct drm_device *dev)
+static u32 intel_panel_get_backlight(struct drm_device *dev,
+				     enum pipe pipe)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	u32 val;
@@ -450,7 +453,7 @@ static u32 intel_panel_get_backlight(struct drm_device *dev)
 		}
 	}
 
-	val = intel_panel_compute_brightness(dev, val);
+	val = intel_panel_compute_brightness(dev, pipe, val);
 
 	spin_unlock_irqrestore(&dev_priv->backlight.lock, flags);
 
@@ -466,19 +469,19 @@ static void intel_pch_panel_set_backlight(struct drm_device *dev, u32 level)
 }
 
 static void intel_panel_actually_set_backlight(struct drm_device *dev,
-					       u32 level)
+					       enum pipe pipe, u32 level)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	u32 tmp;
 
 	DRM_DEBUG_DRIVER("set backlight PWM = %d\n", level);
-	level = intel_panel_compute_brightness(dev, level);
+	level = intel_panel_compute_brightness(dev, pipe, level);
 
 	if (HAS_PCH_SPLIT(dev))
 		return intel_pch_panel_set_backlight(dev, level);
 
 	if (is_backlight_combination_mode(dev)) {
-		u32 max = intel_panel_get_max_backlight(dev);
+		u32 max = intel_panel_get_max_backlight(dev, pipe);
 		u8 lbpc;
 
 		/* we're screwed, but keep behaviour backwards compatible */
@@ -498,15 +501,21 @@ static void intel_panel_actually_set_backlight(struct drm_device *dev,
 }
 
 /* set backlight brightness to level in range [0..max] */
-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)
 {
+	struct drm_device *dev = connector->base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
+	enum pipe pipe = intel_get_pipe_from_connector(connector);
 	u32 freq;
 	unsigned long flags;
 
+	if (pipe == INVALID_PIPE)
+		return;
+
 	spin_lock_irqsave(&dev_priv->backlight.lock, flags);
 
-	freq = intel_panel_get_max_backlight(dev);
+	freq = intel_panel_get_max_backlight(dev, pipe);
 	if (!freq) {
 		/* we are screwed, bail out */
 		goto out;
@@ -523,16 +532,21 @@ void intel_panel_set_backlight(struct drm_device *dev, u32 level, u32 max)
 		dev_priv->backlight.device->props.brightness = level;
 
 	if (dev_priv->backlight.enabled)
-		intel_panel_actually_set_backlight(dev, level);
+		intel_panel_actually_set_backlight(dev, pipe, level);
 out:
 	spin_unlock_irqrestore(&dev_priv->backlight.lock, flags);
 }
 
-void intel_panel_disable_backlight(struct drm_device *dev)
+void intel_panel_disable_backlight(struct intel_connector *connector)
 {
+	struct drm_device *dev = connector->base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
+	enum pipe pipe = intel_get_pipe_from_connector(connector);
 	unsigned long flags;
 
+	if (pipe == INVALID_PIPE)
+		return;
+
 	/*
 	 * Do not disable backlight on the vgaswitcheroo path. When switching
 	 * away from i915, the other client may depend on i915 to handle the
@@ -547,7 +561,7 @@ void intel_panel_disable_backlight(struct drm_device *dev)
 	spin_lock_irqsave(&dev_priv->backlight.lock, flags);
 
 	dev_priv->backlight.enabled = false;
-	intel_panel_actually_set_backlight(dev, 0);
+	intel_panel_actually_set_backlight(dev, pipe, 0);
 
 	if (INTEL_INFO(dev)->gen >= 4) {
 		uint32_t reg, tmp;
@@ -566,18 +580,23 @@ void intel_panel_disable_backlight(struct drm_device *dev)
 	spin_unlock_irqrestore(&dev_priv->backlight.lock, flags);
 }
 
-void intel_panel_enable_backlight(struct drm_device *dev,
-				  enum pipe pipe)
+void intel_panel_enable_backlight(struct intel_connector *connector)
 {
+	struct drm_device *dev = connector->base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
+	enum pipe pipe = intel_get_pipe_from_connector(connector);
 	enum transcoder cpu_transcoder =
 		intel_pipe_to_cpu_transcoder(dev_priv, pipe);
 	unsigned long flags;
 
+	if (pipe == INVALID_PIPE)
+		return;
+
 	spin_lock_irqsave(&dev_priv->backlight.lock, flags);
 
 	if (dev_priv->backlight.level == 0) {
-		dev_priv->backlight.level = intel_panel_get_max_backlight(dev);
+		dev_priv->backlight.level = intel_panel_get_max_backlight(dev,
+									  pipe);
 		if (dev_priv->backlight.device)
 			dev_priv->backlight.device->props.brightness =
 				dev_priv->backlight.level;
@@ -627,7 +646,8 @@ set_level:
 	 * registers are set.
 	 */
 	dev_priv->backlight.enabled = true;
-	intel_panel_actually_set_backlight(dev, dev_priv->backlight.level);
+	intel_panel_actually_set_backlight(dev, pipe,
+					   dev_priv->backlight.level);
 
 	spin_unlock_irqrestore(&dev_priv->backlight.lock, flags);
 }
@@ -650,7 +670,7 @@ static void intel_panel_init_backlight(struct drm_device *dev)
 
 	intel_panel_init_backlight_regs(dev);
 
-	dev_priv->backlight.level = intel_panel_get_backlight(dev);
+	dev_priv->backlight.level = intel_panel_get_backlight(dev, 0);
 	dev_priv->backlight.enabled = dev_priv->backlight.level != 0;
 }
 
@@ -679,16 +699,34 @@ intel_panel_detect(struct drm_device *dev)
 #if IS_ENABLED(CONFIG_BACKLIGHT_CLASS_DEVICE)
 static int intel_panel_update_status(struct backlight_device *bd)
 {
-	struct drm_device *dev = bl_get_data(bd);
-	intel_panel_set_backlight(dev, bd->props.brightness,
+	struct intel_connector *connector = bl_get_data(bd);
+	struct drm_device *dev = connector->base.dev;
+
+	mutex_lock(&dev->mode_config.mutex);
+	intel_panel_set_backlight(connector, bd->props.brightness,
 				  bd->props.max_brightness);
+	mutex_unlock(&dev->mode_config.mutex);
 	return 0;
 }
 
 static int intel_panel_get_brightness(struct backlight_device *bd)
 {
-	struct drm_device *dev = bl_get_data(bd);
-	return intel_panel_get_backlight(dev);
+	struct intel_connector *connector = bl_get_data(bd);
+	struct drm_device *dev = connector->base.dev;
+	enum pipe pipe;
+	int ret = 0;
+
+	mutex_lock(&dev->mode_config.mutex);
+	pipe = intel_get_pipe_from_connector(connector);
+	mutex_unlock(&dev->mode_config.mutex);
+	if (pipe == INVALID_PIPE) {
+		ret = 0;
+		goto out;
+	}
+
+	ret = intel_panel_get_backlight(connector->base.dev, pipe);
+out:
+	return ret;
 }
 
 static const struct backlight_ops intel_panel_bl_ops = {
@@ -708,12 +746,13 @@ int intel_panel_setup_backlight(struct drm_connector *connector)
 	if (WARN_ON(dev_priv->backlight.device))
 		return -ENODEV;
 
+	/* Just create a device for pipe 0 */
 	memset(&props, 0, sizeof(props));
 	props.type = BACKLIGHT_RAW;
 	props.brightness = dev_priv->backlight.level;
 
 	spin_lock_irqsave(&dev_priv->backlight.lock, flags);
-	props.max_brightness = intel_panel_get_max_backlight(dev);
+	props.max_brightness = intel_panel_get_max_backlight(dev, 0);
 	spin_unlock_irqrestore(&dev_priv->backlight.lock, flags);
 
 	if (props.max_brightness == 0) {
@@ -722,7 +761,8 @@ int intel_panel_setup_backlight(struct drm_connector *connector)
 	}
 	dev_priv->backlight.device =
 		backlight_device_register("intel_backlight",
-					  &connector->kdev, dev,
+					  &connector->kdev,
+					  to_intel_connector(connector),
 					  &intel_panel_bl_ops, &props);
 
 	if (IS_ERR(dev_priv->backlight.device)) {
-- 
1.8.3.1