Revert "of/irq: Support #msi-cells=<0> in of_msi_get_domain"

This reverts commit 46f24a5.

drivers/of/irq.c

@@ -781,22 +781,42 @@ struct irq_domain *of_msi_map_get_device_domain(struct device *dev, u32 rid)
  * @np: device node for @dev
  * @token: bus type for this domain
  *
- * Parse the msi-parent property and returns the corresponding MSI domain.
+ * Parse the msi-parent property (both the simple and the complex
+ * versions), and returns the corresponding MSI domain.
  *
  * Returns: the MSI domain for this device (or NULL on failure).
  */
 struct irq_domain *of_msi_get_domain(struct device *dev,
 				     struct device_node *np,
 				     enum irq_domain_bus_token token)
 {
-	struct of_phandle_iterator it;
+	struct device_node *msi_np;
 	struct irq_domain *d;
-	int err;
 
-	of_for_each_phandle(&it, err, np, "msi-parent", "#msi-cells", 0) {
-		d = irq_find_matching_host(it.node, token);
-		if (d)
-			return d;
+	/* Check for a single msi-parent property */
+	msi_np = of_parse_phandle(np, "msi-parent", 0);
+	if (msi_np && !of_property_read_bool(msi_np, "#msi-cells")) {
+		d = irq_find_matching_host(msi_np, token);
+		if (!d)
+			of_node_put(msi_np);
+		return d;
+	}
+
+	if (token == DOMAIN_BUS_PLATFORM_MSI) {
+		/* Check for the complex msi-parent version */
+		struct of_phandle_args args;
+		int index = 0;
+
+		while (!of_parse_phandle_with_args(np, "msi-parent",
+						   "#msi-cells",
+						   index, &args)) {
+			d = irq_find_matching_host(args.np, token);
+			if (d)
+				return d;
+
+			of_node_put(args.np);
+			index++;
+		}
 	}
 
 	return NULL;