drm/i915: use the initialized backlight max value instead of reading it

We now have the max backlight value cached. Use it.

Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

1 files changed, 24 insertions, 21 deletions

diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c
index ed6b1eccb7dd..9a55b36370b3 100644
--- a/drivers/gpu/drm/i915/intel_panel.c
+++ b/drivers/gpu/drm/i915/intel_panel.c
@@ -436,9 +436,6 @@ static u32 vlv_get_max_backlight(struct intel_connector *connector)
         return _vlv_get_max_backlight(dev, pipe);
 }
 
-/* XXX: query mode clock or hardware clock and program max PWM appropriately
- * when it's 0.
- */
 static u32 intel_panel_get_max_backlight(struct intel_connector *connector)
 {
         struct drm_device *dev = connector->base.dev;
@@ -466,15 +463,16 @@ static u32 intel_panel_compute_brightness(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;
+
+        WARN_ON(panel->backlight.max == 0);
 
         if (i915_panel_invert_brightness < 0)
                 return val;
 
         if (i915_panel_invert_brightness > 0 ||
             dev_priv->quirks & QUIRK_INVERT_BRIGHTNESS) {
-                u32 max = intel_panel_get_max_backlight(connector);
-                if (max)
-                        return max - val;
+                return panel->backlight.max - val;
         }
 
         return val;
@@ -555,17 +553,15 @@ static void i9xx_set_backlight(struct intel_connector *connector, u32 level)
 {
         struct drm_device *dev = connector->base.dev;
         struct drm_i915_private *dev_priv = dev->dev_private;
+        struct intel_panel *panel = &connector->panel;
         u32 tmp, mask;
 
+        WARN_ON(panel->backlight.max == 0);
+
         if (is_backlight_combination_mode(dev)) {
-                u32 max = intel_panel_get_max_backlight(connector);
                 u8 lbpc;
 
-                /* we're screwed, but keep behaviour backwards compatible */
-                if (!max)
-                        max = 1;
-
-                lbpc = level * 0xfe / max + 1;
+                lbpc = level * 0xfe / panel->backlight.max + 1;
                 level /= lbpc;
                 pci_write_config_byte(dev->pdev, PCI_LBPC, lbpc);
         }
@@ -620,13 +616,10 @@ void intel_panel_set_backlight(struct intel_connector *connector, u32 level,
 
         spin_lock_irqsave(&dev_priv->backlight_lock, flags);
 
-        freq = intel_panel_get_max_backlight(connector);
-        if (!freq) {
-                /* we are screwed, bail out */
-                goto out;
-        }
+        WARN_ON(panel->backlight.max == 0);
 
-        /* scale to hardware, but be careful to not overflow */
+        /* scale to hardware max, but be careful to not overflow */
+        freq = panel->backlight.max;
         if (freq < max)
                 level = level * freq / max;
         else
@@ -638,7 +631,7 @@ void intel_panel_set_backlight(struct intel_connector *connector, u32 level,
 
         if (panel->backlight.enabled)
                 intel_panel_actually_set_backlight(connector, level);
-out:
+
         spin_unlock_irqrestore(&dev_priv->backlight_lock, flags);
 }
 
@@ -839,8 +832,13 @@ void intel_panel_enable_backlight(struct intel_connector *connector)
 
         spin_lock_irqsave(&dev_priv->backlight_lock, flags);
 
+        /* XXX: transitional, call to make sure freq is set */
+        intel_panel_get_max_backlight(connector);
+
+        WARN_ON(panel->backlight.max == 0);
+
         if (panel->backlight.level == 0) {
-                panel->backlight.level = intel_panel_get_max_backlight(connector);
+                panel->backlight.level = panel->backlight.max;
                 if (panel->backlight.device)
                         panel->backlight.device->props.brightness =
                                 panel->backlight.level;
@@ -960,7 +958,12 @@ static void intel_backlight_device_unregister(struct intel_connector *connector)
 }
 #endif /* CONFIG_BACKLIGHT_CLASS_DEVICE */
 
-/* Note: The setup hooks can't assume pipe is set! */
+/*
+ * Note: The setup hooks can't assume pipe is set!
+ *
+ * XXX: Query mode clock or hardware clock and program PWM modulation frequency
+ * appropriately when it's 0. Use VBT and/or sane defaults.
+ */
 static int pch_setup_backlight(struct intel_connector *connector)
 {
         struct intel_panel *panel = &connector->panel;