drm/i915/lvds: Restore dithering on native modes for gen2/3
A regression introduced in bee17e5 cleared the dithering bit for native
modes on gen2/3.
Bugzilla: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/711568
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
diff --git a/drivers/gpu/drm/i915/intel_lvds.c b/drivers/gpu/drm/i915/intel_lvds.c
index ace8d5d..bcdba7b 100644
--- a/drivers/gpu/drm/i915/intel_lvds.c
+++ b/drivers/gpu/drm/i915/intel_lvds.c
@@ -261,12 +261,6 @@
return true;
}
- /* Make sure pre-965s set dither correctly */
- if (INTEL_INFO(dev)->gen < 4) {
- if (dev_priv->lvds_dither)
- pfit_control |= PANEL_8TO6_DITHER_ENABLE;
- }
-
/* Native modes don't need fitting */
if (adjusted_mode->hdisplay == mode->hdisplay &&
adjusted_mode->vdisplay == mode->vdisplay)
@@ -374,10 +368,16 @@
}
out:
+ /* If not enabling scaling, be consistent and always use 0. */
if ((pfit_control & PFIT_ENABLE) == 0) {
pfit_control = 0;
pfit_pgm_ratios = 0;
}
+
+ /* Make sure pre-965 set dither correctly */
+ if (INTEL_INFO(dev)->gen < 4 && dev_priv->lvds_dither)
+ pfit_control |= PANEL_8TO6_DITHER_ENABLE;
+
if (pfit_control != intel_lvds->pfit_control ||
pfit_pgm_ratios != intel_lvds->pfit_pgm_ratios) {
intel_lvds->pfit_control = pfit_control;