powerpc: use for_each_child_of_node() macro

Use for_each_child_of_node() macro instead of open coding it.
Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200728022807.87815-1-miaoqinglang@huawei.com

arch/powerpc/platforms/pasemi/misc.c

@@ -56,8 +56,7 @@ static int __init pasemi_register_i2c_devices(void)
 		if (!adap_node)
 			continue;
 
-		node = NULL;
-		while ((node = of_get_next_child(adap_node, node))) {
+		for_each_child_of_node(adap_node, node) {
 			struct i2c_board_info info = {};
 			const u32 *addr;
 			int len;

arch/powerpc/platforms/powermac/low_i2c.c

@@ -629,8 +629,7 @@ static void __init kw_i2c_probe(void)
 			for (i = 0; i < chans; i++)
 				kw_i2c_add(host, np, np, i);
 		} else {
-			for (child = NULL;
-			     (child = of_get_next_child(np, child)) != NULL;) {
+			for_each_child_of_node(np, child) {
 				const u32 *reg = of_get_property(child,
 						"reg", NULL);
 				if (reg == NULL)
@@ -1193,8 +1192,7 @@ static void pmac_i2c_devscan(void (*callback)(struct device_node *dev,
 	 * platform function instance
 	 */
 	list_for_each_entry(bus, &pmac_i2c_busses, link) {
-		for (np = NULL;
-		     (np = of_get_next_child(bus->busnode, np)) != NULL;) {
+		for_each_child_of_node(bus->busnode, np) {
 			struct whitelist_ent *p;
 			/* If multibus, check if device is on that bus */
 			if (bus->flags & pmac_i2c_multibus)

arch/powerpc/platforms/powermac/pfunc_base.c

@@ -114,7 +114,7 @@ static void macio_gpio_init_one(struct macio_chip *macio)
 	 * Ok, got one, we dont need anything special to track them down, so
 	 * we just create them all
 	 */
-	for (gp = NULL; (gp = of_get_next_child(gparent, gp)) != NULL;) {
+	for_each_child_of_node(gparent, gp) {
 		const u32 *reg = of_get_property(gp, "reg", NULL);
 		unsigned long offset;
 		if (reg == NULL)
@@ -133,7 +133,7 @@ static void macio_gpio_init_one(struct macio_chip *macio)
 	    macio->of_node);
 
 	/* And now we run all the init ones */
-	for (gp = NULL; (gp = of_get_next_child(gparent, gp)) != NULL;)
+	for_each_child_of_node(gparent, gp)
 		pmf_do_functions(gp, NULL, 0, PMF_FLAGS_ON_INIT, NULL);
 
 	/* Note: We do not at this point implement the "at sleep" or "at wake"

arch/powerpc/platforms/powermac/udbg_scc.c

@@ -80,7 +80,7 @@ void udbg_scc_init(int force_scc)
 	path = of_get_property(of_chosen, "linux,stdout-path", NULL);
 	if (path != NULL)
 		stdout = of_find_node_by_path(path);
-	for (ch = NULL; (ch = of_get_next_child(escc, ch)) != NULL;) {
+	for_each_child_of_node(escc, ch) {
 		if (ch == stdout)
 			ch_def = of_node_get(ch);
 		if (of_node_name_eq(ch, "ch-a"))