/*
* <linux/gpio.h> - userspace ABI for the GPIO character devices
*
* Copyright (C) 2016 Linus Walleij
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published by
* the Free Software Foundation.
*/
#ifndef _UAPI_GPIO_H_
#define _UAPI_GPIO_H_
#include <linux/ioctl.h>
#include <linux/types.h>
/**
* struct gpiochip_info - Information about a certain GPIO chip
* @name: the Linux kernel name of this GPIO chip
* @label: a functional name for this GPIO chip, such as a product
* number, may be NULL
* @lines: number of GPIO lines on this chip
*/
struct gpiochip_info {
char name[32];
char label[32];
__u32 lines;
};
/* Informational flags */
#define GPIOLINE_FLAG_KERNEL (1UL << 0) /* Line used by the kernel */
#define GPIOLINE_FLAG_IS_OUT (1UL << 1)
#define GPIOLINE_FLAG_ACTIVE_LOW (1UL << 2)
#define GPIOLINE_FLAG_OPEN_DRAIN (1UL << 3)
#define GPIOLINE_FLAG_OPEN_SOURCE (1UL << 4)
/**
* struct gpioline_info - Information about a certain GPIO line
* @line_offset: the local offset on this GPIO device, fill this in when
* requesting the line information from the kernel
* @flags: various flags for this line
* @name: the name of this GPIO line, such as the output pin of the line on the
* chip, a rail or a pin header name on a board, as specified by the gpio
* chip, may be NULL
* @consumer: a functional name for the consumer of this GPIO line as set by
* whatever is using it, will be NULL if there is no current user but may
* also be NULL if the consumer doesn't set this up
*/
struct gpioline_info {
__u32 line_offset;
__u32 flags;
char name[32];
char consumer[32];
};
/* Maximum number of requested handles */
#define GPIOHANDLES_MAX 64
/* Linerequest flags */
#define GPIOHANDLE_REQUEST_INPUT (1UL << 0)
#define GPIOHANDLE_REQUEST_OUTPUT (1UL << 1)
#define GPIOHANDLE_REQUEST_ACTIVE_LOW (1UL << 2)
#define GPIOHANDLE_REQUEST_OPEN_DRAIN (1UL << 3)
#define GPIOHANDLE_REQUEST_OPEN_SOURCE (1UL << 4)
/**
* struct gpiohandle_request - Information about a GPIO handle request
* @lineoffsets: an array desired lines, specified by offset index for the
* associated GPIO device
* @flags: desired flags for the desired GPIO lines, such as
* GPIOHANDLE_REQUEST_OUTPUT, GPIOHANDLE_REQUEST_ACTIVE_LOW etc, OR:ed
* together. Note that even if multiple lines are requested, the same flags
* must be applicable to all of them, if you want lines with individual
* flags set, request them one by one. It is possible to select
* a batch of input or output lines, but they must all have the same
* characteristics, i.e. all inputs or all outputs, all active low etc
* @default_values: if the GPIOHANDLE_REQUEST_OUTPUT is set for a requested
* line, this specifies the default output value, should be 0 (low) or
* 1 (high), anything else than 0 or 1 will be interpreted as 1 (high)
* @consumer_label: a desired consumer label for the selected GPIO line(s)
* such as "my-bitbanged-relay"
* @lines: number of lines requested in this request, i.e. the number of
* valid fields in the above arrays, set to 1 to request a single line
* @fd: if successful this field will contain a valid anonymous file handle
* after a GPIO_GET_LINEHANDLE_IOCTL operation, zero or negative value
* means error
*/
struct gpiohandle_request {
__u32 lineoffsets[GPIOHANDLES_MAX];
__u32 flags;
__u8 default_values[GPIOHANDLES_MAX];
char consumer_label[32];
__u32 lines;
int fd;
};
/**
* struct gpiohandle_data - Information of values on a GPIO handle
* @values: when getting the state of lines this contains the current
* state of a line, when setting the state of lines these should contain
* the desired target state
*/
struct gpiohandle_data {
__u8 values[GPIOHANDLES_MAX];
};
#define GPIOHANDLE_GET_LINE_VALUES_IOCTL _IOWR(0xB4, 0x08, struct gpiohandle_data)
#define GPIOHANDLE_SET_LINE_VALUES_IOCTL _IOWR(0xB4, 0x09, struct gpiohandle_data)
/* Eventrequest flags */
#define GPIOEVENT_REQUEST_RISING_EDGE (1UL << 0)
#define GPIOEVENT_REQUEST_FALLING_EDGE (1UL << 1)
#define GPIOEVENT_REQUEST_BOTH_EDGES ((1UL << 0) | (1UL << 1))
/**
* struct gpioevent_request - Information about a GPIO event request
* @lineoffset: the desired line to subscribe to events from, specified by
* offset index for the associated GPIO device
* @handleflags: desired handle flags for the desired GPIO line, such as
* GPIOHANDLE_REQUEST_ACTIVE_LOW or GPIOHANDLE_REQUEST_OPEN_DRAIN
* @eventflags: desired flags for the desired GPIO event line, such as
* GPIOEVENT_REQUEST_RISING_EDGE or GPIOEVENT_REQUEST_FALLING_EDGE
* @consumer_label: a desired consumer label for the selected GPIO line(s)
* such as "my-listener"
* @fd: if successful this field will contain a valid anonymous file handle
* after a GPIO_GET_LINEEVENT_IOCTL operation, zero or negative value
* means error
*/
struct gpioevent_request {
__u32 lineoffset;
__u32 handleflags;
__u32 eventflags;
char consumer_label[32];
int fd;
};
/**
* GPIO event types
*/
#define GPIOEVENT_EVENT_RISING_EDGE 0x01
#define GPIOEVENT_EVENT_FALLING_EDGE 0x02
/**
* struct gpioevent_data - The actual event being pushed to userspace
* @timestamp: best estimate of time of event occurrence, in nanoseconds
* @id: event identifier
*/
struct gpioevent_data {
__u64 timestamp;
__u32 id;
};
#define GPIO_GET_CHIPINFO_IOCTL _IOR(0xB4, 0x01, struct gpiochip_info)
#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)
#endif /* _UAPI_GPIO_H_ */
