drm/i915: do not access BLC_PWM_CTL2 on pre-gen4 hardware

The BLC_PWM_CTL2 register does not exist before gen4. While at it, do a
slight drive by cleanup of the code.

Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This commit is contained in:
Jani Nikula 2012-12-04 16:36:28 +02:00 committed by Daniel Vetter
parent 633cf8f505
commit bfd7590d3e

View File

@ -130,8 +130,9 @@ static int is_backlight_combination_mode(struct drm_device *dev)
return 0;
}
static u32 i915_read_blc_pwm_ctl(struct drm_i915_private *dev_priv)
static u32 i915_read_blc_pwm_ctl(struct drm_device *dev)
{
struct drm_i915_private *dev_priv = dev->dev_private;
u32 val;
/* Restore the CTL value if it lost, e.g. GPU reset */
@ -141,21 +142,22 @@ static u32 i915_read_blc_pwm_ctl(struct drm_i915_private *dev_priv)
if (dev_priv->regfile.saveBLC_PWM_CTL2 == 0) {
dev_priv->regfile.saveBLC_PWM_CTL2 = val;
} else if (val == 0) {
I915_WRITE(BLC_PWM_PCH_CTL2,
dev_priv->regfile.saveBLC_PWM_CTL2);
val = dev_priv->regfile.saveBLC_PWM_CTL2;
I915_WRITE(BLC_PWM_PCH_CTL2, val);
}
} else {
val = I915_READ(BLC_PWM_CTL);
if (dev_priv->regfile.saveBLC_PWM_CTL == 0) {
dev_priv->regfile.saveBLC_PWM_CTL = val;
dev_priv->regfile.saveBLC_PWM_CTL2 = I915_READ(BLC_PWM_CTL2);
if (INTEL_INFO(dev)->gen >= 4)
dev_priv->regfile.saveBLC_PWM_CTL2 =
I915_READ(BLC_PWM_CTL2);
} else if (val == 0) {
I915_WRITE(BLC_PWM_CTL,
dev_priv->regfile.saveBLC_PWM_CTL);
I915_WRITE(BLC_PWM_CTL2,
dev_priv->regfile.saveBLC_PWM_CTL2);
val = dev_priv->regfile.saveBLC_PWM_CTL;
I915_WRITE(BLC_PWM_CTL, val);
if (INTEL_INFO(dev)->gen >= 4)
I915_WRITE(BLC_PWM_CTL2,
dev_priv->regfile.saveBLC_PWM_CTL2);
}
}
@ -164,10 +166,9 @@ static u32 i915_read_blc_pwm_ctl(struct drm_i915_private *dev_priv)
static u32 _intel_panel_get_max_backlight(struct drm_device *dev)
{
struct drm_i915_private *dev_priv = dev->dev_private;
u32 max;
max = i915_read_blc_pwm_ctl(dev_priv);
max = i915_read_blc_pwm_ctl(dev);
if (HAS_PCH_SPLIT(dev)) {
max >>= 16;