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 (file)
--- 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;

diff --git a/include/drm/drm_mode_config.h b/include/drm/drm_mode_config.h
index 7569f22..33b3a96 100644 (file)
--- a/include/drm/drm_mode_config.h
+++ b/include/drm/drm_mode_config.h
@@ -796,6 +796,14 @@ struct drm_mode_config {
        bool allow_fb_modifiers;
 
        /**
+        * @normalize_zpos:
+        *
+        * If true the drm core will call drm_atomic_normalize_zpos() as part of
+        * atomic mode checking from drm_atomic_helper_check()
+        */
+       bool normalize_zpos;
+
+       /**
         * @modifiers_property: Plane property to list support modifier/format
         * combination.
         */

diff --git a/include/drm/drm_plane.h b/include/drm/drm_plane.h
index f7bf4a4..d6da26d 100644 (file)
--- a/include/drm/drm_plane.h
+++ b/include/drm/drm_plane.h
@@ -51,8 +51,8 @@ struct drm_modeset_acquire_ctx;
  *     plane with a lower ID.
  * @normalized_zpos: normalized value of zpos: unique, range from 0 to N-1
  *     where N is the number of active planes for given crtc. Note that
- *     the driver must call drm_atomic_normalize_zpos() to update this before
- *     it can be trusted.
+ *     the driver must set drm_mode_config.normalize_zpos or call
+ *     drm_atomic_normalize_zpos() to update this before it can be trusted.
  * @src: clipped source coordinates of the plane (in 16.16)
  * @dst: clipped destination coordinates of the plane
  * @state: backpointer to global drm_atomic_state