1 files changed, 86 insertions, 50 deletions

diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c
index 41b3be217493..4d63839bd9b4 100644
--- a/drivers/gpu/drm/i915/intel_panel.c
+++ b/drivers/gpu/drm/i915/intel_panel.c
@@ -521,6 +521,9 @@ static u32 _vlv_get_backlight(struct drm_device *dev, enum pipe pipe)
 {
         struct drm_i915_private *dev_priv = dev->dev_private;
 
+        if (WARN_ON(pipe != PIPE_A && pipe != PIPE_B))
+                return 0;
+
         return I915_READ(VLV_BLC_PWM_CTL(pipe)) & BACKLIGHT_DUTY_CYCLE_MASK;
 }
 
@@ -536,15 +539,17 @@ static u32 intel_panel_get_backlight(struct intel_connector *connector)
 {
         struct drm_device *dev = connector->base.dev;
         struct drm_i915_private *dev_priv = dev->dev_private;
-        u32 val;
-        unsigned long flags;
+        struct intel_panel *panel = &connector->panel;
+        u32 val = 0;
 
-        spin_lock_irqsave(&dev_priv->backlight_lock, flags);
+        mutex_lock(&dev_priv->backlight_lock);
 
-        val = dev_priv->display.get_backlight(connector);
-        val = intel_panel_compute_brightness(connector, val);
+        if (panel->backlight.enabled) {
+                val = dev_priv->display.get_backlight(connector);
+                val = intel_panel_compute_brightness(connector, val);
+        }
 
-        spin_unlock_irqrestore(&dev_priv->backlight_lock, flags);
+        mutex_unlock(&dev_priv->backlight_lock);
 
         DRM_DEBUG_DRIVER("get backlight PWM = %d\n", val);
         return val;
@@ -603,6 +608,9 @@ static void vlv_set_backlight(struct intel_connector *connector, u32 level)
         enum pipe pipe = intel_get_pipe_from_connector(connector);
         u32 tmp;
 
+        if (WARN_ON(pipe != PIPE_A && pipe != PIPE_B))
+                return;
+
         tmp = I915_READ(VLV_BLC_PWM_CTL(pipe)) & ~BACKLIGHT_DUTY_CYCLE_MASK;
         I915_WRITE(VLV_BLC_PWM_CTL(pipe), tmp | level);
 }
@@ -626,14 +634,12 @@ static void intel_panel_set_backlight(struct intel_connector *connector,
         struct drm_device *dev = connector->base.dev;
         struct drm_i915_private *dev_priv = dev->dev_private;
         struct intel_panel *panel = &connector->panel;
-        enum pipe pipe = intel_get_pipe_from_connector(connector);
         u32 hw_level;
-        unsigned long flags;
 
-        if (!panel->backlight.present || pipe == INVALID_PIPE)
+        if (!panel->backlight.present)
                 return;
 
-        spin_lock_irqsave(&dev_priv->backlight_lock, flags);
+        mutex_lock(&dev_priv->backlight_lock);
 
         WARN_ON(panel->backlight.max == 0);
 
@@ -643,7 +649,7 @@ static void intel_panel_set_backlight(struct intel_connector *connector,
         if (panel->backlight.enabled)
                 intel_panel_actually_set_backlight(connector, hw_level);
 
-        spin_unlock_irqrestore(&dev_priv->backlight_lock, flags);
+        mutex_unlock(&dev_priv->backlight_lock);
 }
 
 /* set backlight brightness to level in range [0..max], assuming hw min is
@@ -657,12 +663,17 @@ void intel_panel_set_backlight_acpi(struct intel_connector *connector,
         struct intel_panel *panel = &connector->panel;
         enum pipe pipe = intel_get_pipe_from_connector(connector);
         u32 hw_level;
-        unsigned long flags;
 
+        /*
+         * INVALID_PIPE may occur during driver init because
+         * connection_mutex isn't held across the entire backlight
+         * setup + modeset readout, and the BIOS can issue the
+         * requests at any time.
+         */
         if (!panel->backlight.present || pipe == INVALID_PIPE)
                 return;
 
-        spin_lock_irqsave(&dev_priv->backlight_lock, flags);
+        mutex_lock(&dev_priv->backlight_lock);
 
         WARN_ON(panel->backlight.max == 0);
 
@@ -678,7 +689,7 @@ void intel_panel_set_backlight_acpi(struct intel_connector *connector,
         if (panel->backlight.enabled)
                 intel_panel_actually_set_backlight(connector, hw_level);
 
-        spin_unlock_irqrestore(&dev_priv->backlight_lock, flags);
+        mutex_unlock(&dev_priv->backlight_lock);
 }
 
 static void pch_disable_backlight(struct intel_connector *connector)
@@ -720,6 +731,9 @@ static void vlv_disable_backlight(struct intel_connector *connector)
         enum pipe pipe = intel_get_pipe_from_connector(connector);
         u32 tmp;
 
+        if (WARN_ON(pipe != PIPE_A && pipe != PIPE_B))
+                return;
+
         intel_panel_actually_set_backlight(connector, 0);
 
         tmp = I915_READ(VLV_BLC_PWM_CTL2(pipe));
@@ -731,10 +745,8 @@ 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;
         struct intel_panel *panel = &connector->panel;
-        enum pipe pipe = intel_get_pipe_from_connector(connector);
-        unsigned long flags;
 
-        if (!panel->backlight.present || pipe == INVALID_PIPE)
+        if (!panel->backlight.present)
                 return;
 
         /*
@@ -748,14 +760,14 @@ void intel_panel_disable_backlight(struct intel_connector *connector)
                 return;
         }
 
-        spin_lock_irqsave(&dev_priv->backlight_lock, flags);
+        mutex_lock(&dev_priv->backlight_lock);
 
         if (panel->backlight.device)
                 panel->backlight.device->props.power = FB_BLANK_POWERDOWN;
         panel->backlight.enabled = false;
         dev_priv->display.disable_backlight(connector);
 
-        spin_unlock_irqrestore(&dev_priv->backlight_lock, flags);
+        mutex_unlock(&dev_priv->backlight_lock);
 }
 
 static void bdw_enable_backlight(struct intel_connector *connector)
@@ -779,8 +791,9 @@ static void bdw_enable_backlight(struct intel_connector *connector)
         if (panel->backlight.active_low_pwm)
                 pch_ctl1 |= BLM_PCH_POLARITY;
 
-        /* BDW always uses the pch pwm controls. */
-        pch_ctl1 |= BLM_PCH_OVERRIDE_ENABLE;
+        /* After LPT, override is the default. */
+        if (HAS_PCH_LPT(dev_priv))
+                pch_ctl1 |= BLM_PCH_OVERRIDE_ENABLE;
 
         I915_WRITE(BLC_PWM_PCH_CTL1, pch_ctl1);
         POSTING_READ(BLC_PWM_PCH_CTL1);
@@ -909,6 +922,9 @@ static void vlv_enable_backlight(struct intel_connector *connector)
         enum pipe pipe = intel_get_pipe_from_connector(connector);
         u32 ctl, ctl2;
 
+        if (WARN_ON(pipe != PIPE_A && pipe != PIPE_B))
+                return;
+
         ctl2 = I915_READ(VLV_BLC_PWM_CTL2(pipe));
         if (ctl2 & BLM_PWM_ENABLE) {
                 DRM_DEBUG_KMS("backlight already enabled\n");
@@ -936,14 +952,13 @@ void intel_panel_enable_backlight(struct intel_connector *connector)
         struct drm_i915_private *dev_priv = dev->dev_private;
         struct intel_panel *panel = &connector->panel;
         enum pipe pipe = intel_get_pipe_from_connector(connector);
-        unsigned long flags;
 
-        if (!panel->backlight.present || pipe == INVALID_PIPE)
+        if (!panel->backlight.present)
                 return;
 
         DRM_DEBUG_KMS("pipe %c\n", pipe_name(pipe));
 
-        spin_lock_irqsave(&dev_priv->backlight_lock, flags);
+        mutex_lock(&dev_priv->backlight_lock);
 
         WARN_ON(panel->backlight.max == 0);
 
@@ -961,7 +976,7 @@ void intel_panel_enable_backlight(struct intel_connector *connector)
         if (panel->backlight.device)
                 panel->backlight.device->props.power = FB_BLANK_UNBLANK;
 
-        spin_unlock_irqrestore(&dev_priv->backlight_lock, flags);
+        mutex_unlock(&dev_priv->backlight_lock);
 }
 
 #if IS_ENABLED(CONFIG_BACKLIGHT_CLASS_DEVICE)
@@ -1030,6 +1045,9 @@ static int intel_backlight_device_register(struct intel_connector *connector)
         if (WARN_ON(panel->backlight.device))
                 return -ENODEV;
 
+        if (!panel->backlight.present)
+                return 0;
+
         WARN_ON(panel->backlight.max == 0);
 
         memset(&props, 0, sizeof(props));
@@ -1065,6 +1083,10 @@ static int intel_backlight_device_register(struct intel_connector *connector)
                 panel->backlight.device = NULL;
                 return -ENODEV;
         }
+
+        DRM_DEBUG_KMS("Connector %s backlight sysfs interface registered\n",
+                      connector->base.name);
+
         return 0;
 }
 
@@ -1119,7 +1141,7 @@ static u32 get_backlight_min_vbt(struct intel_connector *connector)
         return scale(min, 0, 255, 0, panel->backlight.max);
 }
 
-static int bdw_setup_backlight(struct intel_connector *connector)
+static int bdw_setup_backlight(struct intel_connector *connector, enum pipe unused)
 {
         struct drm_device *dev = connector->base.dev;
         struct drm_i915_private *dev_priv = dev->dev_private;
@@ -1145,7 +1167,7 @@ static int bdw_setup_backlight(struct intel_connector *connector)
         return 0;
 }
 
-static int pch_setup_backlight(struct intel_connector *connector)
+static int pch_setup_backlight(struct intel_connector *connector, enum pipe unused)
 {
         struct drm_device *dev = connector->base.dev;
         struct drm_i915_private *dev_priv = dev->dev_private;
@@ -1172,7 +1194,7 @@ static int pch_setup_backlight(struct intel_connector *connector)
         return 0;
 }
 
-static int i9xx_setup_backlight(struct intel_connector *connector)
+static int i9xx_setup_backlight(struct intel_connector *connector, enum pipe unused)
 {
         struct drm_device *dev = connector->base.dev;
         struct drm_i915_private *dev_priv = dev->dev_private;
@@ -1204,7 +1226,7 @@ static int i9xx_setup_backlight(struct intel_connector *connector)
         return 0;
 }
 
-static int i965_setup_backlight(struct intel_connector *connector)
+static int i965_setup_backlight(struct intel_connector *connector, enum pipe unused)
 {
         struct drm_device *dev = connector->base.dev;
         struct drm_i915_private *dev_priv = dev->dev_private;
@@ -1234,37 +1256,40 @@ static int i965_setup_backlight(struct intel_connector *connector)
         return 0;
 }
 
-static int vlv_setup_backlight(struct intel_connector *connector)
+static int vlv_setup_backlight(struct intel_connector *connector, enum pipe pipe)
 {
         struct drm_device *dev = connector->base.dev;
         struct drm_i915_private *dev_priv = dev->dev_private;
         struct intel_panel *panel = &connector->panel;
-        enum pipe pipe;
+        enum pipe p;
         u32 ctl, ctl2, val;
 
-        for_each_pipe(dev_priv, pipe) {
-                u32 cur_val = I915_READ(VLV_BLC_PWM_CTL(pipe));
+        for_each_pipe(dev_priv, p) {
+                u32 cur_val = I915_READ(VLV_BLC_PWM_CTL(p));
 
                 /* 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) |
+                I915_WRITE(VLV_BLC_PWM_CTL(p), (0xf42 << 16) |
                            cur_val);
         }
 
-        ctl2 = I915_READ(VLV_BLC_PWM_CTL2(PIPE_A));
+        if (WARN_ON(pipe != PIPE_A && pipe != PIPE_B))
+                return -ENODEV;
+
+        ctl2 = I915_READ(VLV_BLC_PWM_CTL2(pipe));
         panel->backlight.active_low_pwm = ctl2 & BLM_POLARITY_I965;
 
-        ctl = I915_READ(VLV_BLC_PWM_CTL(PIPE_A));
+        ctl = I915_READ(VLV_BLC_PWM_CTL(pipe));
         panel->backlight.max = ctl >> 16;
         if (!panel->backlight.max)
                 return -ENODEV;
 
         panel->backlight.min = get_backlight_min_vbt(connector);
 
-        val = _vlv_get_backlight(dev, PIPE_A);
+        val = _vlv_get_backlight(dev, pipe);
         panel->backlight.level = intel_panel_compute_brightness(connector, val);
 
         panel->backlight.enabled = (ctl2 & BLM_PWM_ENABLE) &&
@@ -1273,13 +1298,12 @@ static int vlv_setup_backlight(struct intel_connector *connector)
         return 0;
 }
 
-int intel_panel_setup_backlight(struct drm_connector *connector)
+int intel_panel_setup_backlight(struct drm_connector *connector, enum pipe pipe)
 {
         struct drm_device *dev = connector->dev;
         struct drm_i915_private *dev_priv = dev->dev_private;
         struct intel_connector *intel_connector = to_intel_connector(connector);
         struct intel_panel *panel = &intel_connector->panel;
-        unsigned long flags;
         int ret;
 
         if (!dev_priv->vbt.backlight.present) {
@@ -1292,9 +1316,9 @@ int intel_panel_setup_backlight(struct drm_connector *connector)
         }
 
         /* set level and max in panel struct */
-        spin_lock_irqsave(&dev_priv->backlight_lock, flags);
-        ret = dev_priv->display.setup_backlight(intel_connector);
-        spin_unlock_irqrestore(&dev_priv->backlight_lock, flags);
+        mutex_lock(&dev_priv->backlight_lock);
+        ret = dev_priv->display.setup_backlight(intel_connector, pipe);
+        mutex_unlock(&dev_priv->backlight_lock);
 
         if (ret) {
                 DRM_DEBUG_KMS("failed to setup backlight for connector %s\n",
@@ -1302,15 +1326,12 @@ int intel_panel_setup_backlight(struct drm_connector *connector)
                 return ret;
         }
 
-        intel_backlight_device_register(intel_connector);
-
         panel->backlight.present = true;
 
-        DRM_DEBUG_KMS("backlight initialized, %s, brightness %u/%u, "
-                      "sysfs interface %sregistered\n",
+        DRM_DEBUG_KMS("Connector %s backlight initialized, %s, brightness %u/%u\n",
+                      connector->name,
                       panel->backlight.enabled ? "enabled" : "disabled",
-                      panel->backlight.level, panel->backlight.max,
-                      panel->backlight.device ? "" : "not ");
+                      panel->backlight.level, panel->backlight.max);
 
         return 0;
 }
@@ -1321,7 +1342,6 @@ void intel_panel_destroy_backlight(struct drm_connector *connector)
         struct intel_panel *panel = &intel_connector->panel;
 
         panel->backlight.present = false;
-        intel_backlight_device_unregister(intel_connector);
 }
 
 /* Set up chip specific backlight functions */
@@ -1329,7 +1349,7 @@ void intel_panel_init_backlight_funcs(struct drm_device *dev)
 {
         struct drm_i915_private *dev_priv = dev->dev_private;
 
-        if (IS_BROADWELL(dev)) {
+        if (IS_BROADWELL(dev) || (INTEL_INFO(dev)->gen >= 9)) {
                 dev_priv->display.setup_backlight = bdw_setup_backlight;
                 dev_priv->display.enable_backlight = bdw_enable_backlight;
                 dev_priv->display.disable_backlight = pch_disable_backlight;
@@ -1384,3 +1404,19 @@ void intel_panel_fini(struct intel_panel *panel)
                 drm_mode_destroy(intel_connector->base.dev,
                                 panel->downclock_mode);
 }
+
+void intel_backlight_register(struct drm_device *dev)
+{
+        struct intel_connector *connector;
+
+        list_for_each_entry(connector, &dev->mode_config.connector_list, base.head)
+                intel_backlight_device_register(connector);
+}
+
+void intel_backlight_unregister(struct drm_device *dev)
+{
+        struct intel_connector *connector;
+
+        list_for_each_entry(connector, &dev->mode_config.connector_list, base.head)
+                intel_backlight_device_unregister(connector);
+}