drm/omap: check if rotation is supported before commit

omapdrm is missing a check on the validity of the rotation property.
This leads to omapdrm possibly trying to use rotation on non-rotateable
framebuffer, which causes the overlay setup to fail.

This patch adds the necessary check to omap_plane_atomic_check().
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

drivers/gpu/drm/omapdrm/omap_drv.h

@@ -189,6 +189,7 @@ void omap_framebuffer_update_scanout(struct drm_framebuffer *fb,
 		struct omap_drm_window *win, struct omap_overlay_info *info);
 struct drm_connector *omap_framebuffer_get_next_connector(
 		struct drm_framebuffer *fb, struct drm_connector *from);
+bool omap_framebuffer_supports_rotation(struct drm_framebuffer *fb);
 
 void omap_gem_init(struct drm_device *dev);
 void omap_gem_deinit(struct drm_device *dev);

drivers/gpu/drm/omapdrm/omap_fb.c

@@ -145,6 +145,14 @@ static uint32_t get_linear_addr(struct plane *plane,
 	return plane->paddr + offset;
 }
 
+bool omap_framebuffer_supports_rotation(struct drm_framebuffer *fb)
+{
+	struct omap_framebuffer *omap_fb = to_omap_framebuffer(fb);
+	struct plane *plane = &omap_fb->planes[0];
+
+	return omap_gem_flags(plane->bo) & OMAP_BO_TILED;
+}
+
 /* update ovl info for scanout, handles cases of multi-planar fb's, etc.
  */
 void omap_framebuffer_update_scanout(struct drm_framebuffer *fb,

drivers/gpu/drm/omapdrm/omap_plane.c

@@ -177,6 +177,12 @@ static int omap_plane_atomic_check(struct drm_plane *plane,
 	if (state->crtc_y + state->crtc_h > crtc_state->adjusted_mode.vdisplay)
 		return -EINVAL;
 
+	if (state->fb) {
+		if (state->rotation != BIT(DRM_ROTATE_0) &&
+		    !omap_framebuffer_supports_rotation(state->fb))
+			return -EINVAL;
+	}
+
 	return 0;
 }