drm: Add drm_mode_config->normalize_zpos boolean
Instead of drivers duplicating the drm_atomic_helper_check() code to be
able to normalize the zpos they can use the normalize_zpos flag to let the
drm core to do it.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180321102029.15248-2-peter.ujfalusi@ti.com
diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index c356545..d63c806 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -875,6 +875,11 @@ EXPORT_SYMBOL(drm_atomic_helper_check_planes);
* functions depend upon an updated adjusted_mode.clock to e.g. properly compute
* watermarks.
*
+ * Note that zpos normalization will add all enable planes to the state which
+ * might not desired for some drivers.
+ * For example enable/disable of a cursor plane which have fixed zpos value
+ * would trigger all other enabled planes to be forced to the state change.
+ *
* RETURNS:
* Zero for success or -errno
*/
@@ -887,6 +892,12 @@ int drm_atomic_helper_check(struct drm_device *dev,
if (ret)
return ret;
+ if (dev->mode_config.normalize_zpos) {
+ ret = drm_atomic_normalize_zpos(dev, state);
+ if (ret)
+ return ret;
+ }
+
ret = drm_atomic_helper_check_planes(dev, state);
if (ret)
return ret;