[PATCH v2] drm/i915: ignore pipe select bit when checking for LVDS register initialization

[Seth Forshee]

The Lenovo Thinkpad T410 has the LVDS_PIPEB_SELECT 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..ae17526 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_PIPE_MASK | LVDS_DETECTED)))
                        val = dev_priv->bios_lvds_val;
                dev_priv->lvds_val = val;
        }
-- 
1.7.9.5