[PATCH] gpiolib: add GPIO_SET_DEBOUNCE_IOCTL

[Hector Bujanda <hector.bujanda@xxxxxxxx>]

This allows calling gpiod_set_debounce function through char device ioctl.

Signed-off-by: Hector Bujanda <hector.bujanda@xxxxxxxx>
---
 drivers/gpio/gpiolib.c    | 12 ++++++++++++
 include/uapi/linux/gpio.h | 12 ++++++++++++
 2 files changed, 24 insertions(+)

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 70f0dedca59f..c959c2962f15 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -1073,6 +1073,18 @@ static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 		if (copy_to_user(ip, &lineinfo, sizeof(lineinfo)))
 			return -EFAULT;
 		return 0;
+	} else if (cmd == GPIO_SET_DEBOUNCE_IOCTL) {
+		struct gpioline_debounce linedebounce;
+		struct gpio_desc *desc;
+
+		if (copy_from_user(&linedebounce, ip, sizeof(linedebounce)))
+			return -EFAULT;
+		if (linedebounce.line_offset >= gdev->ngpio)
+			return -EINVAL;
+
+		desc = &gdev->descs[linedebounce.line_offset];
+
+		return gpiod_set_debounce(desc, linedebounce.debounce_usec);
 	} else if (cmd == GPIO_GET_LINEHANDLE_IOCTL) {
 		return linehandle_create(gdev, ip);
 	} else if (cmd == GPIO_GET_LINEEVENT_IOCTL) {
diff --git a/include/uapi/linux/gpio.h b/include/uapi/linux/gpio.h
index 1bf6e6df084b..4b092990d4c8 100644
--- a/include/uapi/linux/gpio.h
+++ b/include/uapi/linux/gpio.h
@@ -53,6 +53,17 @@ struct gpioline_info {
 	char consumer[32];
 };
 
+/**
+ * struct gpioline_debounce - GPIO line debounce
+ * @line_offset: the local offset on this GPIO device, fill this in when
+ * requesting the line information from the kernel
+ * @debounce_usec: debounce in uSeconds to set for this line
+ */
+struct gpioline_debounce {
+	__u32 line_offset;
+	__u32 debounce_usec;
+};
+
 /* Maximum number of requested handles */
 #define GPIOHANDLES_MAX 64
 
@@ -154,5 +165,6 @@ struct gpioevent_data {
 #define GPIO_GET_LINEINFO_IOCTL _IOWR(0xB4, 0x02, struct gpioline_info)
 #define GPIO_GET_LINEHANDLE_IOCTL _IOWR(0xB4, 0x03, struct gpiohandle_request)
 #define GPIO_GET_LINEEVENT_IOCTL _IOWR(0xB4, 0x04, struct gpioevent_request)
+#define GPIO_SET_DEBOUNCE_IOCTL _IOW(0xB4, 0x05, struct gpioline_debounce)
 
 #endif /* _UAPI_GPIO_H_ */
-- 
2.17.1