[PATCH] drm/i915: ignore LVDS_PIPEB_SELECT when checking for LVDS register initialization

[Seth Forshee]

The Lenovo Thinkpad T410 has this bit set in the LVDS register when
booted with the lid closed, even though the LVDS hasn't really been
initialized. Ignore this bit so that the VBT value will be used instead.

Signed-off-by: Seth Forshee <seth.forshee at canonical.com>
---
 drivers/gpu/drm/i915/intel_display.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index e0aa064..f81f249 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -434,7 +434,7 @@ static bool is_dual_link_lvds(struct drm_i915_private *dev_priv,
 		 * register is uninitialized.
 		 */
 		val = I915_READ(reg);
-		if (!(val & ~LVDS_DETECTED))
+		if (!(val & ~(LVDS_PIPEB_SELECT | LVDS_DETECTED)))
 			val = dev_priv->bios_lvds_val;
 		dev_priv->lvds_val = val;
 	}