/* SPDX-License-Identifier: GPL-2.0-only WITH Linux-syscall-note */ /* * - 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 #include #include /* * The maximum size of name and label arrays. * * Must be a multiple of 8 to ensure 32/64-bit alignment of structs. */ #define GPIO_MAX_NAME_SIZE 32 /** * 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 empty (i.e. label[0] == '\0') * @lines: number of GPIO lines on this chip */ struct gpiochip_info { char name[GPIO_MAX_NAME_SIZE]; char label[GPIO_MAX_NAME_SIZE]; __u32 lines; }; /* * Maximum number of requested lines. * * Must be no greater than 64, as bitmaps are restricted here to 64-bits * for simplicity, and a multiple of 2 to ensure 32/64-bit alignment of * structs. */ #define GPIO_V2_LINES_MAX 64 /* * The maximum number of configuration attributes associated with a line * request. */ #define GPIO_V2_LINE_NUM_ATTRS_MAX 10 /** * enum gpio_v2_line_flag - &struct gpio_v2_line_attribute.flags values * @GPIO_V2_LINE_FLAG_USED: line is not available for request * @GPIO_V2_LINE_FLAG_ACTIVE_LOW: line active state is physical low * @GPIO_V2_LINE_FLAG_INPUT: line is an input * @GPIO_V2_LINE_FLAG_OUTPUT: line is an output * @GPIO_V2_LINE_FLAG_EDGE_RISING: line detects rising (inactive to active) * edges * @GPIO_V2_LINE_FLAG_EDGE_FALLING: line detects falling (active to * inactive) edges * @GPIO_V2_LINE_FLAG_OPEN_DRAIN: line is an open drain output * @GPIO_V2_LINE_FLAG_OPEN_SOURCE: line is an open source output * @GPIO_V2_LINE_FLAG_BIAS_PULL_UP: line has pull-up bias enabled * @GPIO_V2_LINE_FLAG_BIAS_PULL_DOWN: line has pull-down bias enabled * @GPIO_V2_LINE_FLAG_BIAS_DISABLED: line has bias disabled * @GPIO_V2_LINE_FLAG_EVENT_CLOCK_REALTIME: line events contain REALTIME timestamps */ enum gpio_v2_line_flag { GPIO_V2_LINE_FLAG_USED = _BITULL(0), GPIO_V2_LINE_FLAG_ACTIVE_LOW = _BITULL(1), GPIO_V2_LINE_FLAG_INPUT = _BITULL(2), GPIO_V2_LINE_FLAG_OUTPUT = _BITULL(3), GPIO_V2_LINE_FLAG_EDGE_RISING = _BITULL(4), GPIO_V2_LINE_FLAG_EDGE_FALLING = _BITULL(5), GPIO_V2_LINE_FLAG_OPEN_DRAIN = _BITULL(6), GPIO_V2_LINE_FLAG_OPEN_SOURCE = _BITULL(7), GPIO_V2_LINE_FLAG_BIAS_PULL_UP = _BITULL(8), GPIO_V2_LINE_FLAG_BIAS_PULL_DOWN = _BITULL(9), GPIO_V2_LINE_FLAG_BIAS_DISABLED = _BITULL(10), GPIO_V2_LINE_FLAG_EVENT_CLOCK_REALTIME = _BITULL(11), }; /** * struct gpio_v2_line_values - Values of GPIO lines * @bits: a bitmap containing the value of the lines, set to 1 for active * and 0 for inactive. * @mask: a bitmap identifying the lines to get or set, with each bit * number corresponding to the index into &struct * gpio_v2_line_request.offsets. */ struct gpio_v2_line_values { __aligned_u64 bits; __aligned_u64 mask; }; /** * enum gpio_v2_line_attr_id - &struct gpio_v2_line_attribute.id values * identifying which field of the attribute union is in use. * @GPIO_V2_LINE_ATTR_ID_FLAGS: flags field is in use * @GPIO_V2_LINE_ATTR_ID_OUTPUT_VALUES: values field is in use * @GPIO_V2_LINE_ATTR_ID_DEBOUNCE: debounce_period_us field is in use */ enum gpio_v2_line_attr_id { GPIO_V2_LINE_ATTR_ID_FLAGS = 1, GPIO_V2_LINE_ATTR_ID_OUTPUT_VALUES = 2, GPIO_V2_LINE_ATTR_ID_DEBOUNCE = 3, }; /** * struct gpio_v2_line_attribute - a configurable attribute of a line * @id: attribute identifier with value from &enum gpio_v2_line_attr_id * @padding: reserved for future use and must be zero filled * @flags: if id is %GPIO_V2_LINE_ATTR_ID_FLAGS, the flags for the GPIO * line, with values from &enum gpio_v2_line_flag, such as * %GPIO_V2_LINE_FLAG_ACTIVE_LOW, %GPIO_V2_LINE_FLAG_OUTPUT etc, added * together. This overrides the default flags contained in the &struct * gpio_v2_line_config for the associated line. * @values: if id is %GPIO_V2_LINE_ATTR_ID_OUTPUT_VALUES, a bitmap * containing the values to which the lines will be set, with each bit * number corresponding to the index into &struct * gpio_v2_line_request.offsets. * @debounce_period_us: if id is %GPIO_V2_LINE_ATTR_ID_DEBOUNCE, the * desired debounce period, in microseconds */ struct gpio_v2_line_attribute { __u32 id; __u32 padding; union { __aligned_u64 flags; __aligned_u64 values; __u32 debounce_period_us; }; }; /** * struct gpio_v2_line_config_attribute - a configuration attribute * associated with one or more of the requested lines. * @attr: the configurable attribute * @mask: a bitmap identifying the lines to which the attribute applies, * with each bit number corresponding to the index into &struct * gpio_v2_line_request.offsets. */ struct gpio_v2_line_config_attribute { struct gpio_v2_line_attribute attr; __aligned_u64 mask; }; /** * struct gpio_v2_line_config - Configuration for GPIO lines * @flags: flags for the GPIO lines, with values from &enum * gpio_v2_line_flag, such as %GPIO_V2_LINE_FLAG_ACTIVE_LOW, * %GPIO_V2_LINE_FLAG_OUTPUT etc, added together. This is the default for * all requested lines but may be overridden for particular lines using * @attrs. * @num_attrs: the number of attributes in @attrs * @padding: reserved for future use and must be zero filled * @attrs: the configuration attributes associated with the requested * lines. Any attribute should only be associated with a particular line * once. If an attribute is associated with a line multiple times then the * first occurrence (i.e. lowest index) has precedence. */ struct gpio_v2_line_config { __aligned_u64 flags; __u32 num_attrs; /* Pad to fill implicit padding and reserve space for future use. */ __u32 padding[5]; struct gpio_v2_line_config_attribute attrs[GPIO_V2_LINE_NUM_ATTRS_MAX]; }; /** * struct gpio_v2_line_request - Information about a request for GPIO lines * @offsets: an array of desired lines, specified by offset index for the * associated GPIO chip * @consumer: a desired consumer label for the selected GPIO lines such as * "my-bitbanged-relay" * @config: requested configuration for the lines. * @num_lines: number of lines requested in this request, i.e. the number * of valid fields in the %GPIO_V2_LINES_MAX sized arrays, set to 1 to * request a single line * @event_buffer_size: a suggested minimum number of line events that the * kernel should buffer. This is only relevant if edge detection is * enabled in the configuration. Note that this is only a suggested value * and the kernel may allocate a larger buffer or cap the size of the * buffer. If this field is zero then the buffer size defaults to a minimum * of @num_lines * 16. * @padding: reserved for future use and must be zero filled * @fd: if successful this field will contain a valid anonymous file handle * after a %GPIO_GET_LINE_IOCTL operation, zero or negative value means * error */ struct gpio_v2_line_request { __u32 offsets[GPIO_V2_LINES_MAX]; char consumer[GPIO_MAX_NAME_SIZE]; struct gpio_v2_line_config config; __u32 num_lines; __u32 event_buffer_size; /* Pad to fill implicit padding and reserve space for future use. */ __u32 padding[5]; __s32 fd; }; /** * struct gpio_v2_line_info - Information about a certain GPIO 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 empty (i.e. name[0] == '\0') * @consumer: a functional name for the consumer of this GPIO line as set * by whatever is using it, will be empty if there is no current user but * may also be empty if the consumer doesn't set this up * @offset: the local offset on this GPIO chip, fill this in when * requesting the line information from the kernel * @num_attrs: the number of attributes in @attrs * @flags: flags for this GPIO line, with values from &enum * gpio_v2_line_flag, such as %GPIO_V2_LINE_FLAG_ACTIVE_LOW, * %GPIO_V2_LINE_FLAG_OUTPUT etc, added together. * @attrs: the configuration attributes associated with the line * @padding: reserved for future use */ struct gpio_v2_line_info { char name[GPIO_MAX_NAME_SIZE]; char consumer[GPIO_MAX_NAME_SIZE]; __u32 offset; __u32 num_attrs; __aligned_u64 flags; struct gpio_v2_line_attribute attrs[GPIO_V2_LINE_NUM_ATTRS_MAX]; /* Space reserved for future use. */ __u32 padding[4]; }; /** * enum gpio_v2_line_changed_type - &struct gpio_v2_line_changed.event_type * values * @GPIO_V2_LINE_CHANGED_REQUESTED: line has been requested * @GPIO_V2_LINE_CHANGED_RELEASED: line has been released * @GPIO_V2_LINE_CHANGED_CONFIG: line has been reconfigured */ enum gpio_v2_line_changed_type { GPIO_V2_LINE_CHANGED_REQUESTED = 1, GPIO_V2_LINE_CHANGED_RELEASED = 2, GPIO_V2_LINE_CHANGED_CONFIG = 3, }; /** * struct gpio_v2_line_info_changed - Information about a change in status * of a GPIO line * @info: updated line information * @timestamp_ns: estimate of time of status change occurrence, in nanoseconds * @event_type: the type of change with a value from &enum * gpio_v2_line_changed_type * @padding: reserved for future use */ struct gpio_v2_line_info_changed { struct gpio_v2_line_info info; __aligned_u64 timestamp_ns; __u32 event_type; /* Pad struct to 64-bit boundary and reserve space for future use. */ __u32 padding[5]; }; /** * enum gpio_v2_line_event_id - &struct gpio_v2_line_event.id values * @GPIO_V2_LINE_EVENT_RISING_EDGE: event triggered by a rising edge * @GPIO_V2_LINE_EVENT_FALLING_EDGE: event triggered by a falling edge */ enum gpio_v2_line_event_id { GPIO_V2_LINE_EVENT_RISING_EDGE = 1, GPIO_V2_LINE_EVENT_FALLING_EDGE = 2, }; /** * struct gpio_v2_line_event - The actual event being pushed to userspace * @timestamp_ns: best estimate of time of event occurrence, in nanoseconds. * @id: event identifier with value from &enum gpio_v2_line_event_id * @offset: the offset of the line that triggered the event * @seqno: the sequence number for this event in the sequence of events for * all the lines in this line request * @line_seqno: the sequence number for this event in the sequence of * events on this particular line * @padding: reserved for future use * * By default the @timestamp_ns is read from %CLOCK_MONOTONIC and is * intended to allow the accurate measurement of the time between events. * It does not provide the wall-clock time. * * If the %GPIO_V2_LINE_FLAG_EVENT_CLOCK_REALTIME flag is set then the * @timestamp_ns is read from %CLOCK_REALTIME. */ struct gpio_v2_line_event { __aligned_u64 timestamp_ns; __u32 id; __u32 offset; __u32 seqno; __u32 line_seqno; /* Space reserved for future use. */ __u32 padding[6]; }; /* * ABI v1 * * This version of the ABI is deprecated. * Use the latest version of the ABI, defined above, instead. */ /* 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) #define GPIOLINE_FLAG_BIAS_PULL_UP (1UL << 5) #define GPIOLINE_FLAG_BIAS_PULL_DOWN (1UL << 6) #define GPIOLINE_FLAG_BIAS_DISABLE (1UL << 7) /** * 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 empty (i.e. name[0] == '\0') * @consumer: a functional name for the consumer of this GPIO line as set by * whatever is using it, will be empty if there is no current user but may * also be empty if the consumer doesn't set this up * * Note: This struct is part of ABI v1 and is deprecated. * Use &struct gpio_v2_line_info instead. */ struct gpioline_info { __u32 line_offset; __u32 flags; char name[GPIO_MAX_NAME_SIZE]; char consumer[GPIO_MAX_NAME_SIZE]; }; /* Maximum number of requested handles */ #define GPIOHANDLES_MAX 64 /* Possible line status change events */ enum { GPIOLINE_CHANGED_REQUESTED = 1, GPIOLINE_CHANGED_RELEASED, GPIOLINE_CHANGED_CONFIG, }; /** * struct gpioline_info_changed - Information about a change in status * of a GPIO line * @info: updated line information * @timestamp: estimate of time of status change occurrence, in nanoseconds * @event_type: one of %GPIOLINE_CHANGED_REQUESTED, * %GPIOLINE_CHANGED_RELEASED and %GPIOLINE_CHANGED_CONFIG * @padding: reserved for future use * * The &struct gpioline_info embedded here has 32-bit alignment on its own, * but it works fine with 64-bit alignment too. With its 72 byte size, we can * guarantee there are no implicit holes between it and subsequent members. * The 20-byte padding at the end makes sure we don't add any implicit padding * at the end of the structure on 64-bit architectures. * * Note: This struct is part of ABI v1 and is deprecated. * Use &struct gpio_v2_line_info_changed instead. */ struct gpioline_info_changed { struct gpioline_info info; __u64 timestamp; __u32 event_type; __u32 padding[5]; /* for future use */ }; /* 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) #define GPIOHANDLE_REQUEST_BIAS_PULL_UP (1UL << 5) #define GPIOHANDLE_REQUEST_BIAS_PULL_DOWN (1UL << 6) #define GPIOHANDLE_REQUEST_BIAS_DISABLE (1UL << 7) /** * struct gpiohandle_request - Information about a GPIO handle request * @lineoffsets: an array of 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, added * 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 * * Note: This struct is part of ABI v1 and is deprecated. * Use &struct gpio_v2_line_request instead. */ struct gpiohandle_request { __u32 lineoffsets[GPIOHANDLES_MAX]; __u32 flags; __u8 default_values[GPIOHANDLES_MAX]; char consumer_label[GPIO_MAX_NAME_SIZE]; __u32 lines; int fd; }; /** * struct gpiohandle_config - Configuration for a GPIO handle request * @flags: updated flags for the requested GPIO lines, such as * %GPIOHANDLE_REQUEST_OUTPUT, %GPIOHANDLE_REQUEST_ACTIVE_LOW etc, added * together * @default_values: if the %GPIOHANDLE_REQUEST_OUTPUT is set in flags, * 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) * @padding: reserved for future use and should be zero filled * * Note: This struct is part of ABI v1 and is deprecated. * Use &struct gpio_v2_line_config instead. */ struct gpiohandle_config { __u32 flags; __u8 default_values[GPIOHANDLES_MAX]; __u32 padding[4]; /* padding for future use */ }; /** * 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 * * Note: This struct is part of ABI v1 and is deprecated. * Use &struct gpio_v2_line_values instead. */ struct gpiohandle_data { __u8 values[GPIOHANDLES_MAX]; }; /* 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 * * Note: This struct is part of ABI v1 and is deprecated. * Use &struct gpio_v2_line_request instead. */ struct gpioevent_request { __u32 lineoffset; __u32 handleflags; __u32 eventflags; char consumer_label[GPIO_MAX_NAME_SIZE]; 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 * * Note: This struct is part of ABI v1 and is deprecated. * Use &struct gpio_v2_line_event instead. */ struct gpioevent_data { __u64 timestamp; __u32 id; }; /* * v1 and v2 ioctl()s */ #define GPIO_GET_CHIPINFO_IOCTL _IOR(0xB4, 0x01, struct gpiochip_info) #define GPIO_GET_LINEINFO_UNWATCH_IOCTL _IOWR(0xB4, 0x0C, __u32) /* * v2 ioctl()s */ #define GPIO_V2_GET_LINEINFO_IOCTL _IOWR(0xB4, 0x05, struct gpio_v2_line_info) #define GPIO_V2_GET_LINEINFO_WATCH_IOCTL _IOWR(0xB4, 0x06, struct gpio_v2_line_info) #define GPIO_V2_GET_LINE_IOCTL _IOWR(0xB4, 0x07, struct gpio_v2_line_request) #define GPIO_V2_LINE_SET_CONFIG_IOCTL _IOWR(0xB4, 0x0D, struct gpio_v2_line_config) #define GPIO_V2_LINE_GET_VALUES_IOCTL _IOWR(0xB4, 0x0E, struct gpio_v2_line_values) #define GPIO_V2_LINE_SET_VALUES_IOCTL _IOWR(0xB4, 0x0F, struct gpio_v2_line_values) /* * v1 ioctl()s * * These ioctl()s are deprecated. Use the v2 equivalent instead. */ #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) #define GPIOHANDLE_GET_LINE_VALUES_IOCTL _IOWR(0xB4, 0x08, struct gpiohandle_data) #define GPIOHANDLE_SET_LINE_VALUES_IOCTL _IOWR(0xB4, 0x09, struct gpiohandle_data) #define GPIOHANDLE_SET_CONFIG_IOCTL _IOWR(0xB4, 0x0A, struct gpiohandle_config) #define GPIO_GET_LINEINFO_WATCH_IOCTL _IOWR(0xB4, 0x0B, struct gpioline_info) #endif /* _GPIO_H_ */