File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/include/linux/gpio_keys.h b/include/linux/gpio_keys.h
new file mode 100644
index 0000000..ee2d8c6
--- /dev/null
+++ b/include/linux/gpio_keys.h
@@ -0,0 +1,58 @@
+#ifndef _GPIO_KEYS_H
+#define _GPIO_KEYS_H
+
+struct device;
+struct gpio_desc;
+
+/**
+ * struct gpio_keys_button - configuration parameters
+ * @code:		input event code (KEY_*, SW_*)
+ * @gpio:		%-1 if this key does not support gpio
+ * @active_low:		%true indicates that button is considered
+ *			depressed when gpio is low
+ * @desc:		label that will be attached to button's gpio
+ * @type:		input event type (%EV_KEY, %EV_SW, %EV_ABS)
+ * @wakeup:		configure the button as a wake-up source
+ * @debounce_interval:	debounce ticks interval in msecs
+ * @can_disable:	%true indicates that userspace is allowed to
+ *			disable button via sysfs
+ * @value:		axis value for %EV_ABS
+ * @irq:		Irq number in case of interrupt keys
+ * @gpiod:		GPIO descriptor
+ */
+struct gpio_keys_button {
+	unsigned int code;
+	int gpio;
+	int active_low;
+	const char *desc;
+	unsigned int type;
+	int wakeup;
+	int debounce_interval;
+	bool can_disable;
+	int value;
+	unsigned int irq;
+	struct gpio_desc *gpiod;
+};
+
+/**
+ * struct gpio_keys_platform_data - platform data for gpio_keys driver
+ * @buttons:		pointer to array of &gpio_keys_button structures
+ *			describing buttons attached to the device
+ * @nbuttons:		number of elements in @buttons array
+ * @poll_interval:	polling interval in msecs - for polling driver only
+ * @rep:		enable input subsystem auto repeat
+ * @enable:		platform hook for enabling the device
+ * @disable:		platform hook for disabling the device
+ * @name:		input device name
+ */
+struct gpio_keys_platform_data {
+	struct gpio_keys_button *buttons;
+	int nbuttons;
+	unsigned int poll_interval;
+	unsigned int rep:1;
+	int (*enable)(struct device *dev);
+	void (*disable)(struct device *dev);
+	const char *name;
+};
+
+#endif