OMAPDSS: APPLY: add dss_ovl_simple_check()

Add dss_ovl_simple_check() which is used to check the validity of
certain overlay attributes. Only attributes that can be checked
independently, without knowing the display being used, is done here
(thus "simple").

We can use this function in dss_ovl_set_info().
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drivers/video/omap2/dss/apply.c

@@ -928,12 +928,52 @@ int dss_mgr_unset_device(struct omap_overlay_manager *mgr)
 }
 
 
+static int dss_ovl_simple_check(struct omap_overlay *ovl,
+		const struct omap_overlay_info *info)
+{
+	if (info->paddr == 0) {
+		DSSERR("check_overlay: paddr cannot be 0\n");
+		return -EINVAL;
+	}
+
+	if ((ovl->caps & OMAP_DSS_OVL_CAP_SCALE) == 0) {
+		if (info->out_width != 0 && info->width != info->out_width) {
+			DSSERR("check_overlay: overlay %d doesn't support "
+					"scaling\n", ovl->id);
+			return -EINVAL;
+		}
+
+		if (info->out_height != 0 && info->height != info->out_height) {
+			DSSERR("check_overlay: overlay %d doesn't support "
+					"scaling\n", ovl->id);
+			return -EINVAL;
+		}
+	}
+
+	if ((ovl->supported_modes & info->color_mode) == 0) {
+		DSSERR("check_overlay: overlay %d doesn't support mode %d\n",
+				ovl->id, info->color_mode);
+		return -EINVAL;
+	}
+
+	if (info->zorder >= omap_dss_get_num_overlays()) {
+		DSSERR("check_overlay: zorder %d too high\n", info->zorder);
+		return -EINVAL;
+	}
+
+	return 0;
+}
 
 int dss_ovl_set_info(struct omap_overlay *ovl,
 		struct omap_overlay_info *info)
 {
 	struct ovl_priv_data *op = get_ovl_priv(ovl);
 	unsigned long flags;
+	int r;
+
+	r = dss_ovl_simple_check(ovl, info);
+	if (r)
+		return r;
 
 	spin_lock_irqsave(&data_lock, flags);