---

yaml
---
r: 178855
b: refs/heads/master
c: e5a95eb
h: refs/heads/master
i:
  178853: 6d3eacd
  178851: c6d87b7
  178847: 996f3a2
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 8faf3b317471179c02db339aa80955a2e88c036d
+refs/heads/master: e5a95eb778690bc864eb330202d2c1b974caaeb4

trunk/drivers/gpu/drm/i915/intel_display.c

@@ -2993,6 +2993,18 @@ static int intel_crtc_mode_set(struct drm_crtc *crtc,
 
 		/* determine panel color depth */
 		temp = I915_READ(pipeconf_reg);
+		temp &= ~PIPE_BPC_MASK;
+		if (is_lvds) {
+			int lvds_reg = I915_READ(PCH_LVDS);
+			/* the BPC will be 6 if it is 18-bit LVDS panel */
+			if ((lvds_reg & LVDS_A3_POWER_MASK) == LVDS_A3_POWER_UP)
+				temp |= PIPE_8BPC;
+			else
+				temp |= PIPE_6BPC;
+		} else
+			temp |= PIPE_8BPC;
+		I915_WRITE(pipeconf_reg, temp);
+		I915_READ(pipeconf_reg);
 
 		switch (temp & PIPE_BPC_MASK) {
 		case PIPE_8BPC: