@@ -30,6 +30,10 @@
#include "intel_drv.h"
+#define PCI_LBPC 0xf4 /* legacy/combination backlight modes */
+#define BLM_COMBINATION_MODE (1 << 30)
+#define BLM_LEGACY_MODE (1 << 16)
+
void
intel_fixed_panel_mode(struct drm_display_mode *fixed_mode,
struct drm_display_mode *adjusted_mode)
@@ -110,6 +114,22 @@ done:
dev_priv->pch_pf_size = (width << 16) | height;
}
+/*
+ * What about gen 3? If there are no gen 3 systems with ASLE,
+ * then it doesn't matter, as we don't need to change the
+ * brightness. But then the gen 2 check can be removed too.
+ */
+static int is_backlight_combination_mode(struct drm_device *dev)
+{
+ struct drm_i915_private *dev_priv = dev->dev_private;
+
+ if (INTEL_INFO(dev)->gen >= 4)
+ return I915_READ(BLC_PWM_CTL2) & BLM_COMBINATION_MODE;
+ if (IS_GEN2(dev))
+ return I915_READ(BLC_PWM_CTL) & BLM_LEGACY_MODE;
+ return 0;
+}
+
static u32 i915_read_blc_pwm_ctl(struct drm_i915_private *dev_priv)
{
u32 val;
@@ -163,9 +183,12 @@ u32 intel_panel_get_max_backlight(struct drm_device *dev)
max >>= 17;
} else {
max >>= 16;
+ /* Ignore BLM_LEGACY_MODE bit */
if (INTEL_INFO(dev)->gen < 4)
max &= ~1;
}
+ if (is_backlight_combination_mode(dev))
+ max *= 0xff;
}
DRM_DEBUG_DRIVER("max backlight PWM = %d\n", max);
@@ -183,6 +206,12 @@ u32 intel_panel_get_backlight(struct drm_device *dev)
val = I915_READ(BLC_PWM_CTL) & BACKLIGHT_DUTY_CYCLE_MASK;
if (IS_PINEVIEW(dev))
val >>= 1;
+ if (is_backlight_combination_mode(dev)){
+ u8 lbpc;
+
+ pci_read_config_byte(dev->pdev, PCI_LBPC, &lbpc);
+ val *= lbpc;
+ }
}
DRM_DEBUG_DRIVER("get backlight PWM = %d\n", val);
@@ -205,6 +234,15 @@ void intel_panel_set_backlight(struct drm_device *dev, u32 level)
if (HAS_PCH_SPLIT(dev))
return intel_pch_panel_set_backlight(dev, level);
+
+ if (level && is_backlight_combination_mode(dev)){
+ u32 max = intel_panel_get_max_backlight(dev);
+ u8 lpbc;
+
+ lpbc = level * 0xff / max;
+ level /= lpbc;
+ pci_write_config_byte(dev->pdev, PCI_LBPC, lpbc);
+ }
tmp = I915_READ(BLC_PWM_CTL);
if (IS_PINEVIEW(dev)) {
tmp &= ~(BACKLIGHT_DUTY_CYCLE_MASK - 1);