drm/i915: Disable VGA output when doing DRM_MODE_DPMS_OFF.

Signed-off-by: Ma Ling <ling.ma@intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
diff --git a/drivers/gpu/drm/i915/intel_crt.c b/drivers/gpu/drm/i915/intel_crt.c
index af26028..954b859 100644
--- a/drivers/gpu/drm/i915/intel_crt.c
+++ b/drivers/gpu/drm/i915/intel_crt.c
@@ -46,7 +46,7 @@
 
 	temp = I915_READ(reg);
 	temp &= ~(ADPA_HSYNC_CNTL_DISABLE | ADPA_VSYNC_CNTL_DISABLE);
-	temp |= ADPA_DAC_ENABLE;
+	temp &= ~ADPA_DAC_ENABLE;
 
 	switch(mode) {
 	case DRM_MODE_DPMS_ON: