/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ /* * <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 _GPIO_H_ #define _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 /* _GPIO_H_ */

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