TV_DAC
I915_WRITE(TV_DAC, I915_READ(TV_DAC) & TV_DAC_SAVE);
save_tv_dac = tv_dac = I915_READ(TV_DAC);
I915_WRITE(TV_DAC, tv_dac);
POSTING_READ(TV_DAC);
tv_dac = I915_READ(TV_DAC);
I915_WRITE(TV_DAC, save_tv_dac & ~TVDAC_STATE_CHG_EN);
save_tv_dac = I915_READ(TV_DAC);
I915_WRITE(TV_DAC, save_tv_dac | TVDAC_STATE_CHG_EN);
tv_dac_on = I915_READ(TV_DAC);
I915_WRITE(TV_DAC, save_tv_dac & ~TVDAC_STATE_CHG_EN);
tv_dac_off = I915_READ(TV_DAC);
I915_WRITE(TV_DAC, save_tv_dac);