* Takashi Iwai -- Thursday 05 May 2011: > Try the fixed patch below. > --- > diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h > index 456f404..4c6e187 100644 > --- a/drivers/gpu/drm/i915/i915_drv.h > +++ b/drivers/gpu/drm/i915/i915_drv.h > @@ -332,6 +332,7 @@ typedef struct drm_i915_private { > struct intel_overlay *overlay; > > /* LVDS info */ > + int backlight_combination_mode; /* 0=unknown, -1=no, 1=yes */ > int backlight_level; /* restore backlight to this value */ > bool backlight_enabled; > struct drm_display_mode *panel_fixed_mode; > diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c > index f8f86e5..5a6be04 100644 > --- a/drivers/gpu/drm/i915/intel_panel.c > +++ b/drivers/gpu/drm/i915/intel_panel.c > @@ -115,14 +115,24 @@ done: > 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; > + int combo_mode; > + u8 lbpc; > + > + if (dev_priv->backlight_combination_mode) > + return dev_priv->backlight_combination_mode > 0; > + > + pci_read_config_byte(dev->pdev, PCI_LBPC, &lbpc); > + if (!lbpc) > + combo_mode = 0; > + else if (INTEL_INFO(dev)->gen >= 4) > + combo_mode = I915_READ(BLC_PWM_CTL2) & BLM_COMBINATION_MODE; > + else if (IS_GEN2(dev)) > + combo_mode = I915_READ(BLC_PWM_CTL) & BLM_LEGACY_MODE; > + else > + combo_mode = 0; > + > + dev_priv->backlight_combination_mode = combo_mode ? 1 : -1; > + return combo_mode; > } > > static u32 i915_read_blc_pwm_ctl(struct drm_i915_private *dev_priv) The first patch had a problem. Without the lbpc check for zero the backlight still stayed off and could only be activated with the brightness-down key. This revised patch works correctly for me. Thanks! m. _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel