forked from Minki/linux
drm/i915: fix opregion backlight chip detect and range
BLC_PWM_CTL2 is for 965+ only, so add device model check for legacy backlight control. For native backlight control, it maps the backlight value (0~255) in opregion ASLE[BCLP] to backlight duty cycle (0~max_backlight) and set into control register. It also add support for IGD device, which follows opregion spec. Signed-off-by: Li Peng <peng.li@intel.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This commit is contained in:
parent
8dd81a381e
commit
078a033f45
@ -148,6 +148,7 @@ static u32 asle_set_backlight(struct drm_device *dev, u32 bclp)
|
||||
struct drm_i915_private *dev_priv = dev->dev_private;
|
||||
struct opregion_asle *asle = dev_priv->opregion.asle;
|
||||
u32 blc_pwm_ctl, blc_pwm_ctl2;
|
||||
u32 max_backlight, level, shift;
|
||||
|
||||
if (!(bclp & ASLE_BCLP_VALID))
|
||||
return ASLE_BACKLIGHT_FAIL;
|
||||
@ -157,14 +158,25 @@ static u32 asle_set_backlight(struct drm_device *dev, u32 bclp)
|
||||
return ASLE_BACKLIGHT_FAIL;
|
||||
|
||||
blc_pwm_ctl = I915_READ(BLC_PWM_CTL);
|
||||
blc_pwm_ctl &= ~BACKLIGHT_DUTY_CYCLE_MASK;
|
||||
blc_pwm_ctl2 = I915_READ(BLC_PWM_CTL2);
|
||||
|
||||
if (blc_pwm_ctl2 & BLM_COMBINATION_MODE)
|
||||
if (IS_I965G(dev) && (blc_pwm_ctl2 & BLM_COMBINATION_MODE))
|
||||
pci_write_config_dword(dev->pdev, PCI_LBPC, bclp);
|
||||
else
|
||||
I915_WRITE(BLC_PWM_CTL, blc_pwm_ctl | ((bclp * 0x101)-1));
|
||||
|
||||
else {
|
||||
if (IS_IGD(dev)) {
|
||||
blc_pwm_ctl &= ~(BACKLIGHT_DUTY_CYCLE_MASK - 1);
|
||||
max_backlight = (blc_pwm_ctl & BACKLIGHT_MODULATION_FREQ_MASK) >>
|
||||
BACKLIGHT_MODULATION_FREQ_SHIFT;
|
||||
shift = BACKLIGHT_DUTY_CYCLE_SHIFT + 1;
|
||||
} else {
|
||||
blc_pwm_ctl &= ~BACKLIGHT_DUTY_CYCLE_MASK;
|
||||
max_backlight = ((blc_pwm_ctl & BACKLIGHT_MODULATION_FREQ_MASK) >>
|
||||
BACKLIGHT_MODULATION_FREQ_SHIFT) * 2;
|
||||
shift = BACKLIGHT_DUTY_CYCLE_SHIFT;
|
||||
}
|
||||
level = (bclp * max_backlight) / 255;
|
||||
I915_WRITE(BLC_PWM_CTL, blc_pwm_ctl | (level << shift));
|
||||
}
|
||||
asle->cblv = (bclp*0x64)/0xff | ASLE_CBLV_VALID;
|
||||
|
||||
return 0;
|
||||
|
Loading…
Reference in New Issue
Block a user