| #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 |
