drm/msm/mdp5: Remove redundant zpos initialisation

The mdp KMS driver will call drm_plane_create_zpos_property() with an
init value depending on the plane purpose.

Since the initial value wasn't carried over in the state, the driver had
to set it again in mdp5_plane_reset(). However, the helpers have been
adjusted to set it properly at reset, so this is not needed anymore.

Cc: freedreno@lists.freedesktop.org
Cc: linux-arm-msm@vger.kernel.org
Cc: Abhinav Kumar <quic_abhinavk@quicinc.com>
Cc: Rob Clark <robdclark@gmail.com>
Cc: Sean Paul <sean@poorly.run>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20220221095918.18763-13-maxime@cerno.tech

drivers/gpu/drm/msm/disp/mdp5/mdp5_plane.c

@@ -48,6 +48,8 @@ static void mdp5_plane_destroy(struct drm_plane *plane)
 static void mdp5_plane_install_properties(struct drm_plane *plane,
 		struct drm_mode_object *obj)
 {
+	unsigned int zpos;
+
 	drm_plane_create_rotation_property(plane,
 					   DRM_MODE_ROTATE_0,
 					   DRM_MODE_ROTATE_0 |
@@ -59,7 +61,12 @@ static void mdp5_plane_install_properties(struct drm_plane *plane,
 			BIT(DRM_MODE_BLEND_PIXEL_NONE) |
 			BIT(DRM_MODE_BLEND_PREMULTI) |
 			BIT(DRM_MODE_BLEND_COVERAGE));
-	drm_plane_create_zpos_property(plane, 1, 1, 255);
+
+	if (plane->type == DRM_PLANE_TYPE_PRIMARY)
+		zpos = STAGE_BASE;
+	else
+		zpos = STAGE0 + drm_plane_index(plane);
+	drm_plane_create_zpos_property(plane, zpos, 1, 255);
 }
 
 static void
@@ -91,13 +98,6 @@ static void mdp5_plane_reset(struct drm_plane *plane)
 
 	kfree(to_mdp5_plane_state(plane->state));
 	mdp5_state = kzalloc(sizeof(*mdp5_state), GFP_KERNEL);
-
-	if (plane->type == DRM_PLANE_TYPE_PRIMARY)
-		mdp5_state->base.zpos = STAGE_BASE;
-	else
-		mdp5_state->base.zpos = STAGE0 + drm_plane_index(plane);
-	mdp5_state->base.normalized_zpos = mdp5_state->base.zpos;
-
 	__drm_atomic_helper_plane_reset(plane, &mdp5_state->base);
 }