1 files changed, 18 insertions, 0 deletions

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 317004fd94fb..29a7e6b1be5d 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -1010,6 +1010,24 @@ int __gpio_cansleep(unsigned gpio)
 }
 EXPORT_SYMBOL_GPL(__gpio_cansleep);
 
+/**
+ * __gpio_to_irq() - return the IRQ corresponding to a GPIO
+ * @gpio: gpio whose IRQ will be returned (already requested)
+ * Context: any
+ *
+ * This is used directly or indirectly to implement gpio_to_irq().
+ * It returns the number of the IRQ signaled by this (input) GPIO,
+ * or a negative errno.
+ */
+int __gpio_to_irq(unsigned gpio)
+{
+        struct gpio_chip        *chip;
+
+        chip = gpio_to_chip(gpio);
+        return chip->to_irq ? chip->to_irq(chip, gpio - chip->base) : -ENXIO;
+}
+EXPORT_SYMBOL_GPL(__gpio_to_irq);
+
 
 
 /* There's no value in making it easy to inline GPIO calls that may sleep.