1 files changed, 32 insertions, 0 deletions

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 713ca0e37f23..73fd328f6fe4 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -1153,6 +1153,38 @@ int gpiochip_remove(struct gpio_chip *chip)
 }
 EXPORT_SYMBOL_GPL(gpiochip_remove);
 
+/**
+ * gpiochip_find() - iterator for locating a specific gpio_chip
+ * @data: data to pass to match function
+ * @callback: Callback function to check gpio_chip
+ *
+ * Similar to bus_find_device.  It returns a reference to a gpio_chip as
+ * determined by a user supplied @match callback.  The callback should return
+ * 0 if the device doesn't match and non-zero if it does.  If the callback is
+ * non-zero, this function will return to the caller and not iterate over any
+ * more gpio_chips.
+ */
+struct gpio_chip *gpiochip_find(void *data,
+                                int (*match)(struct gpio_chip *chip, void *data))
+{
+        struct gpio_chip *chip = NULL;
+        unsigned long flags;
+        int i;
+
+        spin_lock_irqsave(&gpio_lock, flags);
+        for (i = 0; i < ARCH_NR_GPIOS; i++) {
+                if (!gpio_desc[i].chip)
+                        continue;
+
+                if (match(gpio_desc[i].chip, data)) {
+                        chip = gpio_desc[i].chip;
+                        break;
+                }
+        }
+        spin_unlock_irqrestore(&gpio_lock, flags);
+
+        return chip;
+}
 
 /* These "optional" allocation calls help prevent drivers from stomping
  * on each other, and help provide better diagnostics in debugfs.