drm/i915: enable LVDS on Cougarpoint

Fix the transcoder select bit for LVDS on CPT.

Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>

1 files changed, 11 insertions, 4 deletions

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 716ab9ea19b0..606924ef65a6 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -3492,10 +3492,17 @@ static int intel_crtc_mode_set(struct drm_crtc *crtc,
 
                 lvds = I915_READ(lvds_reg);
                 lvds |= LVDS_PORT_EN | LVDS_A0A2_CLKA_POWER_UP;
-                if (pipe == 1)
-                        lvds |= LVDS_PIPEB_SELECT;
-                else
-                        lvds &= ~LVDS_PIPEB_SELECT;
+                if (pipe == 1) {
+                        if (HAS_PCH_CPT(dev))
+                                lvds |= PORT_TRANS_B_SEL_CPT;
+                        else
+                                lvds |= LVDS_PIPEB_SELECT;
+                } else {
+                        if (HAS_PCH_CPT(dev))
+                                lvds &= ~PORT_TRANS_SEL_MASK;
+                        else
+                                lvds &= ~LVDS_PIPEB_SELECT;
+                }
                 /* set the corresponsding LVDS_BORDER bit */
                 lvds |= dev_priv->lvds_border_bits;
                 /* Set the B0-B3 data pairs corresponding to whether we're going to