drm: rcar: use generic code for managing zpos plane property

version 6:
rebased patch on top rcar-du changes for zpos

version 4:
fix null pointer issue while setting zpos in plane reset function

This patch replaces zpos property handling custom code in rcar DRM
driver with calls to generic DRM code.

Signed-off-by: Benjamin Gaignard <[e-mail]>
Reviewed-by: Laurent Pinchart <[e-mail]>
Tested-by: Laurent Pinchart <[e-mail]>

Cc: Daniel Vetter <[e-mail]>
Cc: Ville Syrjala <[e-mail]>
Cc: Marek Szyprowski <[e-mail]>

drivers/gpu/drm/rcar-du/rcar_du_crtc.c

···
 
 static unsigned int plane_zpos(struct rcar_du_plane *plane)
 {
-	return to_rcar_plane_state(plane->plane.state)->zpos;
+	return plane->plane.state->normalized_zpos;
 }
 
 static const struct rcar_du_format_info *

drivers/gpu/drm/rcar-du/rcar_du_drv.h

···
 	struct {
 		struct drm_property *alpha;
 		struct drm_property *colorkey;
-		struct drm_property *zpos;
 	} props;
 
 	unsigned int dpad0_source;

drivers/gpu/drm/rcar-du/rcar_du_kms.c

···
 	if (rcdu->props.colorkey == NULL)
 		return -ENOMEM;
 
-	rcdu->props.zpos =
-		drm_property_create_range(rcdu->ddev, 0, "zpos", 1, 7);
-	if (rcdu->props.zpos == NULL)
-		return -ENOMEM;
-
 	return 0;
 }
 

drivers/gpu/drm/rcar-du/rcar_du_plane.c

···
 	state->source = RCAR_DU_PLANE_MEMORY;
 	state->alpha = 255;
 	state->colorkey = RCAR_DU_COLORKEY_NONE;
-	state->zpos = plane->type == DRM_PLANE_TYPE_PRIMARY ? 0 : 1;
+	state->state.zpos = plane->type == DRM_PLANE_TYPE_PRIMARY ? 0 : 1;
 
 	plane->state = &state->state;
 	plane->state->plane = plane;
···
 		rstate->alpha = val;
 	else if (property == rcdu->props.colorkey)
 		rstate->colorkey = val;
-	else if (property == rcdu->props.zpos)
-		rstate->zpos = val;
 	else
 		return -EINVAL;
 
···
 		*val = rstate->alpha;
 	else if (property == rcdu->props.colorkey)
 		*val = rstate->colorkey;
-	else if (property == rcdu->props.zpos)
-		*val = rstate->zpos;
 	else
 		return -EINVAL;
 
···
 		drm_object_attach_property(&plane->plane.base,
 					   rcdu->props.colorkey,
 					   RCAR_DU_COLORKEY_NONE);
-		drm_object_attach_property(&plane->plane.base,
-					   rcdu->props.zpos, 1);
+		drm_plane_create_zpos_property(&plane->plane, 1, 1, 7);
 	}
 
 	return 0;

drivers/gpu/drm/rcar-du/rcar_du_plane.h

···
  * @hwindex: 0-based hardware plane index, -1 means unused
  * @alpha: value of the plane alpha property
  * @colorkey: value of the plane colorkey property
- * @zpos: value of the plane zpos property
  */
 struct rcar_du_plane_state {
 	struct drm_plane_state state;
···
 
 	unsigned int alpha;
 	unsigned int colorkey;
-	unsigned int zpos;
 };
 
 static inline struct rcar_du_plane_state *

drivers/gpu/drm/rcar-du/rcar_du_vsp.c

···
 			.src_y = 0,
 			.src_w = mode->hdisplay << 16,
 			.src_h = mode->vdisplay << 16,
+			.zpos = 0,
 		},
 		.format = rcar_du_format_info(DRM_FORMAT_ARGB8888),
 		.source = RCAR_DU_PLANE_VSPD1,
 		.alpha = 255,
 		.colorkey = 0,
-		.zpos = 0,
 	};
 
 	if (rcdu->info->gen >= 3)
···
 		.pixelformat = 0,
 		.pitch = fb->pitches[0],
 		.alpha = state->alpha,
-		.zpos = state->zpos,
+		.zpos = state->state.zpos,
 	};
 	unsigned int i;
 
···
 		return;
 
 	state->alpha = 255;
-	state->zpos = plane->type == DRM_PLANE_TYPE_PRIMARY ? 0 : 1;
+	state->state.zpos = plane->type == DRM_PLANE_TYPE_PRIMARY ? 0 : 1;
 
 	plane->state = &state->state;
 	plane->state->plane = plane;
···
 
 	if (property == rcdu->props.alpha)
 		rstate->alpha = val;
-	else if (property == rcdu->props.zpos)
-		rstate->zpos = val;
 	else
 		return -EINVAL;
 
···
 
 	if (property == rcdu->props.alpha)
 		*val = rstate->alpha;
-	else if (property == rcdu->props.zpos)
-		*val = rstate->zpos;
 	else
 		return -EINVAL;
 
···
 
 		drm_object_attach_property(&plane->plane.base,
 					   rcdu->props.alpha, 255);
-		drm_object_attach_property(&plane->plane.base,
-					   rcdu->props.zpos, 1);
+		drm_plane_create_zpos_property(&plane->plane, 1, 1,
+					       vsp->num_planes - 1);
 	}
 
 	return 0;