drm/i915: set dither bits on eDP panels too

We really need a macro to test whether a given connector has a panel
attached rather than sprinkling HAS_PCH_SPLIT/IS_eDP/has_edp_encoder
etc all over. In the meantime, fix the bug...

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
[ickle: tidy up the duplicity in the conditionals]
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 948a360..4b23646 100644 (file)
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -3909,11 +3909,6 @@ static int intel_crtc_mode_set(struct drm_crtc *crtc,
                udelay(150);
        }
 
-       if (HAS_PCH_SPLIT(dev)) {
-               pipeconf &= ~PIPECONF_DITHER_EN;
-               pipeconf &= ~PIPECONF_DITHER_TYPE_MASK;
-       }
-
        /* The LVDS pin pair needs to be on before the DPLLs are enabled.
         * This is an exception to the general rule that mode_set doesn't turn
         * things on.
@@ -3951,23 +3946,27 @@ static int intel_crtc_mode_set(struct drm_crtc *crtc,
                 * appropriately here, but we need to look more thoroughly into how
                 * panels behave in the two modes.
                 */
-               /* set the dithering flag */
-               if (IS_I965G(dev)) {
-                       if (dev_priv->lvds_dither) {
-                               if (HAS_PCH_SPLIT(dev)) {
-                                       pipeconf |= PIPECONF_DITHER_EN;
-                                       pipeconf |= PIPECONF_DITHER_TYPE_ST1;
-                               } else
-                                       lvds |= LVDS_ENABLE_DITHER;
-                       } else {
-                               if (!HAS_PCH_SPLIT(dev)) {
-                                       lvds &= ~LVDS_ENABLE_DITHER;
-                               }
-                       }
+               /* set the dithering flag on non-PCH LVDS as needed */
+               if (IS_I965G(dev) && !HAS_PCH_SPLIT(dev)) {
+                       if (dev_priv->lvds_dither)
+                               lvds |= LVDS_ENABLE_DITHER;
+                       else
+                               lvds &= ~LVDS_ENABLE_DITHER;
                }
                I915_WRITE(lvds_reg, lvds);
                I915_READ(lvds_reg);
        }
+
+       /* set the dithering flag and clear for anything other than a panel. */
+       if (HAS_PCH_SPLIT(dev)) {
+               pipeconf &= ~PIPECONF_DITHER_EN;
+               pipeconf &= ~PIPECONF_DITHER_TYPE_MASK;
+               if (dev_priv->lvds_dither && (is_lvds || has_edp_encoder)) {
+                       pipeconf |= PIPECONF_DITHER_EN;
+                       pipeconf |= PIPECONF_DITHER_TYPE_ST1;
+               }
+       }
+
        if (is_dp)
                intel_dp_set_m_n(crtc, mode, adjusted_mode);
        else if (HAS_PCH_SPLIT(dev)) {