BLC_PWM_CTL
ctl = I915_READ(BLC_PWM_CTL);
ctl = I915_READ(BLC_PWM_CTL);
val = I915_READ(BLC_PWM_CTL) & BACKLIGHT_DUTY_CYCLE_MASK;
tmp = I915_READ(BLC_PWM_CTL) & ~mask;
I915_WRITE(BLC_PWM_CTL, tmp | level);
ctl = I915_READ(BLC_PWM_CTL);
I915_WRITE(BLC_PWM_CTL, 0);
I915_WRITE(BLC_PWM_CTL, ctl);
POSTING_READ(BLC_PWM_CTL);
I915_WRITE(BLC_PWM_CTL, ctl);