gpiolib: Split out for_each_gpio_desc() macro

In some cases we want to traverse all GPIO descriptors for given
chip, let's split out for_each_gpio_desc() macro for such cases.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>

drivers/gpio/gpiolib.c

@@ -308,15 +308,10 @@ static struct gpio_desc *gpio_name_to_desc(const char * const name)
 	spin_lock_irqsave(&gpio_lock, flags);
 
 	list_for_each_entry(gdev, &gpio_devices, list) {
-		int i;
-
-		for (i = 0; i != gdev->ngpio; ++i) {
-			struct gpio_desc *desc = &gdev->descs[i];
-
-			if (!desc->name)
-				continue;
+		struct gpio_desc *desc;
 
-			if (!strcmp(desc->name, name)) {
+		for_each_gpio_desc(gdev->chip, desc) {
+			if (desc->name && !strcmp(desc->name, name)) {
 				spin_unlock_irqrestore(&gpio_lock, flags);
 				return desc;
 			}

drivers/gpio/gpiolib.h

@@ -100,10 +100,13 @@ struct gpio_array {
 
 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *gc, unsigned int hwnum);
 
-#define for_each_gpio_desc_with_flag(gc, desc, flag)			\
+#define for_each_gpio_desc(gc, desc)					\
 	for (unsigned int __i = 0;					\
 	     __i < gc->ngpio && (desc = gpiochip_get_desc(gc, __i));	\
 	     __i++)							\
+
+#define for_each_gpio_desc_with_flag(gc, desc, flag)			\
+	for_each_gpio_desc(gc, desc)					\
 		if (!test_bit(flag, &desc->flags)) {} else
 
 int gpiod_get_array_value_complex(bool raw, bool can_sleep,