Bit #28 of the backlight control BLC_PWM_CTL2 is normally used to indicate whether the brightness of the panel backlight is inverted. Sometimes, however, bit #29 is used for this purpose. Add a quirk to mark machines that do so.
Signed-off-by: Carsten Emde <[email protected]> --- drivers/gpu/drm/i915/i915_drv.h | 1 + drivers/gpu/drm/i915/i915_reg.h | 1 + drivers/gpu/drm/i915/intel_display.c | 10 ++++++++++ drivers/gpu/drm/i915/intel_panel.c | 12 ++++++++++-- 4 files changed, 22 insertions(+), 2 deletions(-) Index: linux-tip/drivers/gpu/drm/i915/i915_drv.h =================================================================== --- linux-tip.orig/drivers/gpu/drm/i915/i915_drv.h +++ linux-tip/drivers/gpu/drm/i915/i915_drv.h @@ -295,6 +295,7 @@ enum intel_pch { #define QUIRK_PIPEA_FORCE (1<<0) #define QUIRK_LVDS_SSC_DISABLE (1<<1) +#define QUIRK_ALT_BIT_FOR_BRIGHTNESS_INVERSION (2<<1) struct intel_fbdev; struct intel_fbc_work; Index: linux-tip/drivers/gpu/drm/i915/i915_reg.h =================================================================== --- linux-tip.orig/drivers/gpu/drm/i915/i915_reg.h +++ linux-tip/drivers/gpu/drm/i915/i915_reg.h @@ -1685,6 +1685,7 @@ /* Backlight control */ #define BLC_PWM_CTL2 0x61250 /* 965+ only */ #define BLM_COMBINATION_MODE (1 << 30) +#define BLM_ALT_POLARITY_I965 (1 << 29) /* quirk only */ #define BLM_POLARITY_I965 (1 << 28) /* gen4 only */ #define BLC_PWM_CTL 0x61254 /* Index: linux-tip/drivers/gpu/drm/i915/intel_display.c =================================================================== --- linux-tip.orig/drivers/gpu/drm/i915/intel_display.c +++ linux-tip/drivers/gpu/drm/i915/intel_display.c @@ -9101,6 +9101,16 @@ static void quirk_ssc_force_disable(stru dev_priv->quirks |= QUIRK_LVDS_SSC_DISABLE; } +/* + * A machine may use an alternate bit to indicate panel backlight brightness + * inversion + */ +static void quirk_alt_bit_for_brightness_inversion(struct drm_device *dev) +{ + struct drm_i915_private *dev_priv = dev->dev_private; + dev_priv->quirks |= QUIRK_ALT_BIT_FOR_BRIGHTNESS_INVERSION; +} + struct intel_quirk { int device; int subsystem_vendor; Index: linux-tip/drivers/gpu/drm/i915/intel_panel.c =================================================================== --- linux-tip.orig/drivers/gpu/drm/i915/intel_panel.c +++ linux-tip/drivers/gpu/drm/i915/intel_panel.c @@ -208,9 +208,17 @@ static u32 intel_panel_compute_brightnes dev_priv->quirks & QUIRK_INVERT_BRIGHTNESS) return intel_panel_get_max_backlight(dev) - val; - /* gen4 has a polarity bit */ - if (IS_GEN4(dev) && (I915_READ(BLC_PWM_CTL2) & BLM_POLARITY_I965)) + if (IS_GEN4(dev)) { + /* gen4 has a - possibly quirked - polarity bit */ + int mask; + + if (dev_priv->quirks & QUIRK_ALT_BIT_FOR_BRIGHTNESS_INVERSION) + mask = BLM_ALT_POLARITY_I965; + else + mask = BLM_POLARITY_I965; + if (I915_READ(BLC_PWM_CTL2) & mask) return intel_panel_get_max_backlight(dev) - val; + } return val; } _______________________________________________ Intel-gfx mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/intel-gfx
