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#ifndef _GPIO_DEV_H__
#define _GPIO_DEV_H__
/*********************************************************************
*
* This Linux kernel header is expanded from the original driver
* (gpio_dev) by John Crispin. It provides an ioctl based interface to
* GPIO pins via the /dev/gpio char device and gpiolib within the kernel.
* The third argument to each ioctl is the GPIO pin number.
*
* This driver has been tested with lk 2.6.31 and works. The original
* driver fails quietly with this version. The protocol is now a bit
* different: the ioctl(fd, GPIO_REQUEST, <pin>) should be called
* after the open("/dev/gpio", O_RDWR) to determine if the <pin> is
* already in use. If the ioctl is successful (i.e. returns 0 for not
* in use) then the <pin> is claimed by this driver and
* ioctl(fd, GPIO_FREE, <pin>) should be called prior to close(fd) .
*
* See <kernel_source>/Documentation/gpio.txt
* Note that kernel designers prefer the use of the sysfs gpio interface.
* This char driver is easier to use from code and faster.
********************************************************************/
/* This header can be included in both the user and kernel spaces */
/* The _IO macro is defined in sys/ioctl.h */
#define IOC_GPIODEV_MAGIC 'B'
#define GPIO_GET _IO(IOC_GPIODEV_MAGIC, 10)
#define GPIO_SET _IO(IOC_GPIODEV_MAGIC, 11)
#define GPIO_CLEAR _IO(IOC_GPIODEV_MAGIC, 12)
#define GPIO_DIR_IN _IO(IOC_GPIODEV_MAGIC, 13)
#define GPIO_DIR_OUT _IO(IOC_GPIODEV_MAGIC, 14)
/* Sets the direction out and clears the <pin> (low) */
#define GPIO_DIR_HIGH _IO(IOC_GPIODEV_MAGIC, 15)
/* Sets the direction out and sets the <pin> (high) */
#define GPIO_REQUEST _IO(IOC_GPIODEV_MAGIC, 16)
#define GPIO_FREE _IO(IOC_GPIODEV_MAGIC, 17)
#define GPIO_CAN_SLEEP _IO(IOC_GPIODEV_MAGIC, 18)
#endif
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