drm/i915/tv: Preserve reserved DAC bits during mode-setting
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
diff --git a/drivers/gpu/drm/i915/intel_tv.c b/drivers/gpu/drm/i915/intel_tv.c
index c671f60..fc5c6f2 100644
--- a/drivers/gpu/drm/i915/intel_tv.c
+++ b/drivers/gpu/drm/i915/intel_tv.c
@@ -1196,7 +1196,7 @@
I915_WRITE(TV_V_LUMA_0 + (i<<2), tv_mode->filter_table[j++]);
for (i = 0; i < 43; i++)
I915_WRITE(TV_V_CHROMA_0 + (i<<2), tv_mode->filter_table[j++]);
- I915_WRITE(TV_DAC, 0);
+ I915_WRITE(TV_DAC, I915_READ(TV_DAC) & TV_DAC_SAVE);
I915_WRITE(TV_CTL, tv_ctl);
}