of/gpio: Add new method for getting gpios under different property names

This patch adds a new routine, of_get_named_gpio_flags(), which takes the
property name as a parameter rather than assuming "gpios".

of_get_gpio_flags() is modified to call of_get_named_gpio_flags() with "gpios"
as the property parameter.
Signed-off-by: NJohn Bonesio <bones@secretlab.ca>
[grant.likely: Tidied up whitespace and tweaked kerneldoc comments.]
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

drivers/of/gpio.c

@@ -21,8 +21,9 @@
 #include <linux/slab.h>
 
 /**
- * of_get_gpio_flags - Get a GPIO number and flags to use with GPIO API
+ * of_get_named_gpio_flags() - Get a GPIO number and flags to use with GPIO API
  * @np:		device node to get GPIO from
+ * @propname:	property name containing gpio specifier(s)
  * @index:	index of the GPIO
  * @flags:	a flags pointer to fill in
  *
@@ -30,8 +31,8 @@
  * value on the error condition. If @flags is not NULL the function also fills
  * in flags for the GPIO.
  */
-int of_get_gpio_flags(struct device_node *np, int index,
-		      enum of_gpio_flags *flags)
+int of_get_named_gpio_flags(struct device_node *np, const char *propname,
+                           int index, enum of_gpio_flags *flags)
 {
 	int ret;
 	struct device_node *gpio_np;
@@ -40,7 +41,7 @@ int of_get_gpio_flags(struct device_node *np, int index,
 	const void *gpio_spec;
 	const __be32 *gpio_cells;
 
-	ret = of_parse_phandles_with_args(np, "gpios", "#gpio-cells", index,
+	ret = of_parse_phandles_with_args(np, propname, "#gpio-cells", index,
 					  &gpio_np, &gpio_spec);
 	if (ret) {
 		pr_debug("%s: can't parse gpios property\n", __func__);
@@ -79,7 +80,7 @@ int of_get_gpio_flags(struct device_node *np, int index,
 	pr_debug("%s exited with status %d\n", __func__, ret);
 	return ret;
 }
-EXPORT_SYMBOL(of_get_gpio_flags);
+EXPORT_SYMBOL(of_get_named_gpio_flags);
 
 /**
  * of_gpio_count - Count GPIOs for a device

include/linux/of_gpio.h

@@ -46,8 +46,9 @@ static inline struct of_mm_gpio_chip *to_of_mm_gpio_chip(struct gpio_chip *gc)
 	return container_of(gc, struct of_mm_gpio_chip, gc);
 }
 
-extern int of_get_gpio_flags(struct device_node *np, int index,
-			     enum of_gpio_flags *flags);
+extern int of_get_named_gpio_flags(struct device_node *np,
+		const char *list_name, int index, enum of_gpio_flags *flags);
+
 extern unsigned int of_gpio_count(struct device_node *np);
 
 extern int of_mm_gpiochip_add(struct device_node *np,
@@ -60,8 +61,8 @@ extern struct gpio_chip *of_node_to_gpiochip(struct device_node *np);
 #else /* CONFIG_OF_GPIO */
 
 /* Drivers may not strictly depend on the GPIO support, so let them link. */
-static inline int of_get_gpio_flags(struct device_node *np, int index,
-				    enum of_gpio_flags *flags)
+static inline int of_get_named_gpio_flags(struct device_node *np,
+		const char *list_name, int index, enum of_gpio_flags *flags)
 {
 	return -ENOSYS;
 }
@@ -77,7 +78,38 @@ static inline void of_gpiochip_remove(struct gpio_chip *gc) { }
 #endif /* CONFIG_OF_GPIO */
 
 /**
- * of_get_gpio - Get a GPIO number to use with GPIO API
+ * of_get_gpio_flags() - Get a GPIO number and flags to use with GPIO API
+ * @np:		device node to get GPIO from
+ * @index:	index of the GPIO
+ * @flags:	a flags pointer to fill in
+ *
+ * Returns GPIO number to use with Linux generic GPIO API, or one of the errno
+ * value on the error condition. If @flags is not NULL the function also fills
+ * in flags for the GPIO.
+ */
+static inline int of_get_gpio_flags(struct device_node *np, int index,
+		      enum of_gpio_flags *flags)
+{
+	return of_get_named_gpio_flags(np, "gpios", index, flags);
+}
+
+/**
+ * of_get_named_gpio() - Get a GPIO number to use with GPIO API
+ * @np:		device node to get GPIO from
+ * @propname:	Name of property containing gpio specifier(s)
+ * @index:	index of the GPIO
+ *
+ * Returns GPIO number to use with Linux generic GPIO API, or one of the errno
+ * value on the error condition.
+ */
+static inline int of_get_named_gpio(struct device_node *np,
+                                   const char *propname, int index)
+{
+	return of_get_named_gpio_flags(np, propname, index, NULL);
+}
+
+/**
+ * of_get_gpio() - Get a GPIO number to use with GPIO API
  * @np:		device node to get GPIO from
  * @index:	index of the GPIO
  *