gpio: make gpiochip_get_desc() gpiolib-private

As GPIO descriptors are not going to remain unique anymore, having this
function public is not safe. Restrain its use to gpiolib since we have
no user outside of it.
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpiolib-of.c

@@ -23,7 +23,7 @@
 #include <linux/pinctrl/pinctrl.h>
 #include <linux/slab.h>
 
-struct gpio_desc;
+#include "gpiolib.h"
 
 /* Private data structure for of_gpiochip_find_and_xlate */
 struct gg_data {

drivers/gpio/gpiolib.c

@@ -82,7 +82,6 @@ struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip,
 
 	return &chip->desc[hwnum];
 }
-EXPORT_SYMBOL_GPL(gpiochip_get_desc);
 
 /**
  * Convert a GPIO descriptor to the integer namespace.

drivers/gpio/gpiolib.h

@@ -51,6 +51,8 @@ void gpiochip_free_own_desc(struct gpio_desc *desc);
 struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
 		   const char *list_name, int index, enum of_gpio_flags *flags);
 
+struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, u16 hwnum);
+
 extern struct spinlock gpio_lock;
 extern struct list_head gpio_chips;
 

include/linux/gpio/driver.h

@@ -151,9 +151,6 @@ void gpiod_unlock_as_irq(struct gpio_desc *desc);
 
 struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc);
 
-struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip,
-				    u16 hwnum);
-
 enum gpio_lookup_flags {
 	GPIO_ACTIVE_HIGH = (0 << 0),
 	GPIO_ACTIVE_LOW = (1 << 0),