1 /* SPDX-License-Identifier: GPL-2.0-only WITH Linux-syscall-note */
3 * <linux/gpio.h> - userspace ABI for the GPIO character devices
5 * Copyright (C) 2016 Linus Walleij
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License version 2 as published by
9 * the Free Software Foundation.
14 #include <linux/const.h>
15 #include <linux/ioctl.h>
16 #include <linux/types.h>
19 * The maximum size of name and label arrays.
21 * Must be a multiple of 8 to ensure 32/64-bit alignment of structs.
23 #define GPIO_MAX_NAME_SIZE 32
26 * struct gpiochip_info - Information about a certain GPIO chip
27 * @name: the Linux kernel name of this GPIO chip
28 * @label: a functional name for this GPIO chip, such as a product
29 * number, may be empty (i.e. label[0] == '\0')
30 * @lines: number of GPIO lines on this chip
32 struct gpiochip_info {
33 char name[GPIO_MAX_NAME_SIZE];
34 char label[GPIO_MAX_NAME_SIZE];
39 * Maximum number of requested lines.
41 * Must be no greater than 64, as bitmaps are restricted here to 64-bits
42 * for simplicity, and a multiple of 2 to ensure 32/64-bit alignment of
45 #define GPIO_V2_LINES_MAX 64
48 * The maximum number of configuration attributes associated with a line
51 #define GPIO_V2_LINE_NUM_ATTRS_MAX 10
54 * enum gpio_v2_line_flag - &struct gpio_v2_line_attribute.flags values
55 * @GPIO_V2_LINE_FLAG_USED: line is not available for request
56 * @GPIO_V2_LINE_FLAG_ACTIVE_LOW: line active state is physical low
57 * @GPIO_V2_LINE_FLAG_INPUT: line is an input
58 * @GPIO_V2_LINE_FLAG_OUTPUT: line is an output
59 * @GPIO_V2_LINE_FLAG_EDGE_RISING: line detects rising (inactive to active)
61 * @GPIO_V2_LINE_FLAG_EDGE_FALLING: line detects falling (active to
63 * @GPIO_V2_LINE_FLAG_OPEN_DRAIN: line is an open drain output
64 * @GPIO_V2_LINE_FLAG_OPEN_SOURCE: line is an open source output
65 * @GPIO_V2_LINE_FLAG_BIAS_PULL_UP: line has pull-up bias enabled
66 * @GPIO_V2_LINE_FLAG_BIAS_PULL_DOWN: line has pull-down bias enabled
67 * @GPIO_V2_LINE_FLAG_BIAS_DISABLED: line has bias disabled
68 * @GPIO_V2_LINE_FLAG_EVENT_CLOCK_REALTIME: line events contain REALTIME timestamps
69 * @GPIO_V2_LINE_FLAG_EVENT_CLOCK_HTE: line events contain timestamps from
70 * the hardware timestamping engine (HTE) subsystem
72 enum gpio_v2_line_flag {
73 GPIO_V2_LINE_FLAG_USED = _BITULL(0),
74 GPIO_V2_LINE_FLAG_ACTIVE_LOW = _BITULL(1),
75 GPIO_V2_LINE_FLAG_INPUT = _BITULL(2),
76 GPIO_V2_LINE_FLAG_OUTPUT = _BITULL(3),
77 GPIO_V2_LINE_FLAG_EDGE_RISING = _BITULL(4),
78 GPIO_V2_LINE_FLAG_EDGE_FALLING = _BITULL(5),
79 GPIO_V2_LINE_FLAG_OPEN_DRAIN = _BITULL(6),
80 GPIO_V2_LINE_FLAG_OPEN_SOURCE = _BITULL(7),
81 GPIO_V2_LINE_FLAG_BIAS_PULL_UP = _BITULL(8),
82 GPIO_V2_LINE_FLAG_BIAS_PULL_DOWN = _BITULL(9),
83 GPIO_V2_LINE_FLAG_BIAS_DISABLED = _BITULL(10),
84 GPIO_V2_LINE_FLAG_EVENT_CLOCK_REALTIME = _BITULL(11),
85 GPIO_V2_LINE_FLAG_EVENT_CLOCK_HTE = _BITULL(12),
89 * struct gpio_v2_line_values - Values of GPIO lines
90 * @bits: a bitmap containing the value of the lines, set to 1 for active
92 * @mask: a bitmap identifying the lines to get or set, with each bit
93 * number corresponding to the index into &struct
94 * gpio_v2_line_request.offsets
96 struct gpio_v2_line_values {
102 * enum gpio_v2_line_attr_id - &struct gpio_v2_line_attribute.id values
103 * identifying which field of the attribute union is in use.
104 * @GPIO_V2_LINE_ATTR_ID_FLAGS: flags field is in use
105 * @GPIO_V2_LINE_ATTR_ID_OUTPUT_VALUES: values field is in use
106 * @GPIO_V2_LINE_ATTR_ID_DEBOUNCE: debounce_period_us field is in use
108 enum gpio_v2_line_attr_id {
109 GPIO_V2_LINE_ATTR_ID_FLAGS = 1,
110 GPIO_V2_LINE_ATTR_ID_OUTPUT_VALUES = 2,
111 GPIO_V2_LINE_ATTR_ID_DEBOUNCE = 3,
115 * struct gpio_v2_line_attribute - a configurable attribute of a line
116 * @id: attribute identifier with value from &enum gpio_v2_line_attr_id
117 * @padding: reserved for future use and must be zero filled
118 * @flags: if id is %GPIO_V2_LINE_ATTR_ID_FLAGS, the flags for the GPIO
119 * line, with values from &enum gpio_v2_line_flag, such as
120 * %GPIO_V2_LINE_FLAG_ACTIVE_LOW, %GPIO_V2_LINE_FLAG_OUTPUT etc, added
121 * together. This overrides the default flags contained in the &struct
122 * gpio_v2_line_config for the associated line.
123 * @values: if id is %GPIO_V2_LINE_ATTR_ID_OUTPUT_VALUES, a bitmap
124 * containing the values to which the lines will be set, with each bit
125 * number corresponding to the index into &struct
126 * gpio_v2_line_request.offsets
127 * @debounce_period_us: if id is %GPIO_V2_LINE_ATTR_ID_DEBOUNCE, the
128 * desired debounce period, in microseconds
130 struct gpio_v2_line_attribute {
135 __aligned_u64 values;
136 __u32 debounce_period_us;
141 * struct gpio_v2_line_config_attribute - a configuration attribute
142 * associated with one or more of the requested lines.
143 * @attr: the configurable attribute
144 * @mask: a bitmap identifying the lines to which the attribute applies,
145 * with each bit number corresponding to the index into &struct
146 * gpio_v2_line_request.offsets
148 struct gpio_v2_line_config_attribute {
149 struct gpio_v2_line_attribute attr;
154 * struct gpio_v2_line_config - Configuration for GPIO lines
155 * @flags: flags for the GPIO lines, with values from &enum
156 * gpio_v2_line_flag, such as %GPIO_V2_LINE_FLAG_ACTIVE_LOW,
157 * %GPIO_V2_LINE_FLAG_OUTPUT etc, added together. This is the default for
158 * all requested lines but may be overridden for particular lines using
160 * @num_attrs: the number of attributes in @attrs
161 * @padding: reserved for future use and must be zero filled
162 * @attrs: the configuration attributes associated with the requested
163 * lines. Any attribute should only be associated with a particular line
164 * once. If an attribute is associated with a line multiple times then the
165 * first occurrence (i.e. lowest index) has precedence.
167 struct gpio_v2_line_config {
170 /* Pad to fill implicit padding and reserve space for future use. */
172 struct gpio_v2_line_config_attribute attrs[GPIO_V2_LINE_NUM_ATTRS_MAX];
176 * struct gpio_v2_line_request - Information about a request for GPIO lines
177 * @offsets: an array of desired lines, specified by offset index for the
178 * associated GPIO chip
179 * @consumer: a desired consumer label for the selected GPIO lines such as
180 * "my-bitbanged-relay"
181 * @config: requested configuration for the lines
182 * @num_lines: number of lines requested in this request, i.e. the number
183 * of valid fields in the %GPIO_V2_LINES_MAX sized arrays, set to 1 to
184 * request a single line
185 * @event_buffer_size: a suggested minimum number of line events that the
186 * kernel should buffer. This is only relevant if edge detection is
187 * enabled in the configuration. Note that this is only a suggested value
188 * and the kernel may allocate a larger buffer or cap the size of the
189 * buffer. If this field is zero then the buffer size defaults to a minimum
190 * of @num_lines * 16.
191 * @padding: reserved for future use and must be zero filled
192 * @fd: after a successful %GPIO_V2_GET_LINE_IOCTL operation, contains
193 * a valid anonymous file descriptor representing the request
195 struct gpio_v2_line_request {
196 __u32 offsets[GPIO_V2_LINES_MAX];
197 char consumer[GPIO_MAX_NAME_SIZE];
198 struct gpio_v2_line_config config;
200 __u32 event_buffer_size;
201 /* Pad to fill implicit padding and reserve space for future use. */
207 * struct gpio_v2_line_info - Information about a certain GPIO line
208 * @name: the name of this GPIO line, such as the output pin of the line on
209 * the chip, a rail or a pin header name on a board, as specified by the
210 * GPIO chip, may be empty (i.e. name[0] == '\0')
211 * @consumer: a functional name for the consumer of this GPIO line as set
212 * by whatever is using it, will be empty if there is no current user but
213 * may also be empty if the consumer doesn't set this up
214 * @offset: the local offset on this GPIO chip, fill this in when
215 * requesting the line information from the kernel
216 * @num_attrs: the number of attributes in @attrs
217 * @flags: flags for this GPIO line, with values from &enum
218 * gpio_v2_line_flag, such as %GPIO_V2_LINE_FLAG_ACTIVE_LOW,
219 * %GPIO_V2_LINE_FLAG_OUTPUT etc, added together
220 * @attrs: the configuration attributes associated with the line
221 * @padding: reserved for future use
223 struct gpio_v2_line_info {
224 char name[GPIO_MAX_NAME_SIZE];
225 char consumer[GPIO_MAX_NAME_SIZE];
229 struct gpio_v2_line_attribute attrs[GPIO_V2_LINE_NUM_ATTRS_MAX];
230 /* Space reserved for future use. */
235 * enum gpio_v2_line_changed_type - &struct gpio_v2_line_changed.event_type
237 * @GPIO_V2_LINE_CHANGED_REQUESTED: line has been requested
238 * @GPIO_V2_LINE_CHANGED_RELEASED: line has been released
239 * @GPIO_V2_LINE_CHANGED_CONFIG: line has been reconfigured
241 enum gpio_v2_line_changed_type {
242 GPIO_V2_LINE_CHANGED_REQUESTED = 1,
243 GPIO_V2_LINE_CHANGED_RELEASED = 2,
244 GPIO_V2_LINE_CHANGED_CONFIG = 3,
248 * struct gpio_v2_line_info_changed - Information about a change in status
250 * @info: updated line information
251 * @timestamp_ns: estimate of time of status change occurrence, in nanoseconds
252 * @event_type: the type of change with a value from &enum
253 * gpio_v2_line_changed_type
254 * @padding: reserved for future use
256 struct gpio_v2_line_info_changed {
257 struct gpio_v2_line_info info;
258 __aligned_u64 timestamp_ns;
260 /* Pad struct to 64-bit boundary and reserve space for future use. */
265 * enum gpio_v2_line_event_id - &struct gpio_v2_line_event.id values
266 * @GPIO_V2_LINE_EVENT_RISING_EDGE: event triggered by a rising edge
267 * @GPIO_V2_LINE_EVENT_FALLING_EDGE: event triggered by a falling edge
269 enum gpio_v2_line_event_id {
270 GPIO_V2_LINE_EVENT_RISING_EDGE = 1,
271 GPIO_V2_LINE_EVENT_FALLING_EDGE = 2,
275 * struct gpio_v2_line_event - The actual event being pushed to userspace
276 * @timestamp_ns: best estimate of time of event occurrence, in nanoseconds
277 * @id: event identifier with value from &enum gpio_v2_line_event_id
278 * @offset: the offset of the line that triggered the event
279 * @seqno: the sequence number for this event in the sequence of events for
280 * all the lines in this line request
281 * @line_seqno: the sequence number for this event in the sequence of
282 * events on this particular line
283 * @padding: reserved for future use
285 * By default the @timestamp_ns is read from %CLOCK_MONOTONIC and is
286 * intended to allow the accurate measurement of the time between events.
287 * It does not provide the wall-clock time.
289 * If the %GPIO_V2_LINE_FLAG_EVENT_CLOCK_REALTIME flag is set then the
290 * @timestamp_ns is read from %CLOCK_REALTIME.
292 * If the %GPIO_V2_LINE_FLAG_EVENT_CLOCK_HTE flag is set then the
293 * @timestamp_ns is provided by the hardware timestamping engine (HTE)
296 struct gpio_v2_line_event {
297 __aligned_u64 timestamp_ns;
302 /* Space reserved for future use. */
309 * This version of the ABI is deprecated.
310 * Use the latest version of the ABI, defined above, instead.
313 /* Informational flags */
314 #define GPIOLINE_FLAG_KERNEL (1UL << 0) /* Line used by the kernel */
315 #define GPIOLINE_FLAG_IS_OUT (1UL << 1)
316 #define GPIOLINE_FLAG_ACTIVE_LOW (1UL << 2)
317 #define GPIOLINE_FLAG_OPEN_DRAIN (1UL << 3)
318 #define GPIOLINE_FLAG_OPEN_SOURCE (1UL << 4)
319 #define GPIOLINE_FLAG_BIAS_PULL_UP (1UL << 5)
320 #define GPIOLINE_FLAG_BIAS_PULL_DOWN (1UL << 6)
321 #define GPIOLINE_FLAG_BIAS_DISABLE (1UL << 7)
324 * struct gpioline_info - Information about a certain GPIO line
325 * @line_offset: the local offset on this GPIO device, fill this in when
326 * requesting the line information from the kernel
327 * @flags: various flags for this line
328 * @name: the name of this GPIO line, such as the output pin of the line on the
329 * chip, a rail or a pin header name on a board, as specified by the gpio
330 * chip, may be empty (i.e. name[0] == '\0')
331 * @consumer: a functional name for the consumer of this GPIO line as set by
332 * whatever is using it, will be empty if there is no current user but may
333 * also be empty if the consumer doesn't set this up
335 * Note: This struct is part of ABI v1 and is deprecated.
336 * Use ABI v2 and &struct gpio_v2_line_info instead.
338 struct gpioline_info {
341 char name[GPIO_MAX_NAME_SIZE];
342 char consumer[GPIO_MAX_NAME_SIZE];
345 /* Maximum number of requested handles */
346 #define GPIOHANDLES_MAX 64
348 /* Possible line status change events */
350 GPIOLINE_CHANGED_REQUESTED = 1,
351 GPIOLINE_CHANGED_RELEASED,
352 GPIOLINE_CHANGED_CONFIG,
356 * struct gpioline_info_changed - Information about a change in status
358 * @info: updated line information
359 * @timestamp: estimate of time of status change occurrence, in nanoseconds
360 * @event_type: one of %GPIOLINE_CHANGED_REQUESTED,
361 * %GPIOLINE_CHANGED_RELEASED and %GPIOLINE_CHANGED_CONFIG
362 * @padding: reserved for future use
364 * The &struct gpioline_info embedded here has 32-bit alignment on its own,
365 * but it works fine with 64-bit alignment too. With its 72 byte size, we can
366 * guarantee there are no implicit holes between it and subsequent members.
367 * The 20-byte padding at the end makes sure we don't add any implicit padding
368 * at the end of the structure on 64-bit architectures.
370 * Note: This struct is part of ABI v1 and is deprecated.
371 * Use ABI v2 and &struct gpio_v2_line_info_changed instead.
373 struct gpioline_info_changed {
374 struct gpioline_info info;
377 __u32 padding[5]; /* for future use */
380 /* Linerequest flags */
381 #define GPIOHANDLE_REQUEST_INPUT (1UL << 0)
382 #define GPIOHANDLE_REQUEST_OUTPUT (1UL << 1)
383 #define GPIOHANDLE_REQUEST_ACTIVE_LOW (1UL << 2)
384 #define GPIOHANDLE_REQUEST_OPEN_DRAIN (1UL << 3)
385 #define GPIOHANDLE_REQUEST_OPEN_SOURCE (1UL << 4)
386 #define GPIOHANDLE_REQUEST_BIAS_PULL_UP (1UL << 5)
387 #define GPIOHANDLE_REQUEST_BIAS_PULL_DOWN (1UL << 6)
388 #define GPIOHANDLE_REQUEST_BIAS_DISABLE (1UL << 7)
391 * struct gpiohandle_request - Information about a GPIO handle request
392 * @lineoffsets: an array of desired lines, specified by offset index for the
393 * associated GPIO device
394 * @flags: desired flags for the desired GPIO lines, such as
395 * %GPIOHANDLE_REQUEST_OUTPUT, %GPIOHANDLE_REQUEST_ACTIVE_LOW etc, added
396 * together. Note that even if multiple lines are requested, the same flags
397 * must be applicable to all of them, if you want lines with individual
398 * flags set, request them one by one. It is possible to select
399 * a batch of input or output lines, but they must all have the same
400 * characteristics, i.e. all inputs or all outputs, all active low etc
401 * @default_values: if the %GPIOHANDLE_REQUEST_OUTPUT is set for a requested
402 * line, this specifies the default output value, should be 0 (inactive) or
403 * 1 (active). Anything other than 0 or 1 will be interpreted as active.
404 * @consumer_label: a desired consumer label for the selected GPIO line(s)
405 * such as "my-bitbanged-relay"
406 * @lines: number of lines requested in this request, i.e. the number of
407 * valid fields in the above arrays, set to 1 to request a single line
408 * @fd: after a successful %GPIO_GET_LINEHANDLE_IOCTL operation, contains
409 * a valid anonymous file descriptor representing the request
411 * Note: This struct is part of ABI v1 and is deprecated.
412 * Use ABI v2 and &struct gpio_v2_line_request instead.
414 struct gpiohandle_request {
415 __u32 lineoffsets[GPIOHANDLES_MAX];
417 __u8 default_values[GPIOHANDLES_MAX];
418 char consumer_label[GPIO_MAX_NAME_SIZE];
424 * struct gpiohandle_config - Configuration for a GPIO handle request
425 * @flags: updated flags for the requested GPIO lines, such as
426 * %GPIOHANDLE_REQUEST_OUTPUT, %GPIOHANDLE_REQUEST_ACTIVE_LOW etc, added
428 * @default_values: if the %GPIOHANDLE_REQUEST_OUTPUT is set in flags,
429 * this specifies the default output value, should be 0 (inactive) or
430 * 1 (active). Anything other than 0 or 1 will be interpreted as active.
431 * @padding: reserved for future use and should be zero filled
433 * Note: This struct is part of ABI v1 and is deprecated.
434 * Use ABI v2 and &struct gpio_v2_line_config instead.
436 struct gpiohandle_config {
438 __u8 default_values[GPIOHANDLES_MAX];
439 __u32 padding[4]; /* padding for future use */
443 * struct gpiohandle_data - Information of values on a GPIO handle
444 * @values: when getting the state of lines this contains the current
445 * state of a line, when setting the state of lines these should contain
446 * the desired target state. States are 0 (inactive) or 1 (active).
447 * When setting, anything other than 0 or 1 will be interpreted as active.
449 * Note: This struct is part of ABI v1 and is deprecated.
450 * Use ABI v2 and &struct gpio_v2_line_values instead.
452 struct gpiohandle_data {
453 __u8 values[GPIOHANDLES_MAX];
456 /* Eventrequest flags */
457 #define GPIOEVENT_REQUEST_RISING_EDGE (1UL << 0)
458 #define GPIOEVENT_REQUEST_FALLING_EDGE (1UL << 1)
459 #define GPIOEVENT_REQUEST_BOTH_EDGES ((1UL << 0) | (1UL << 1))
462 * struct gpioevent_request - Information about a GPIO event request
463 * @lineoffset: the desired line to subscribe to events from, specified by
464 * offset index for the associated GPIO device
465 * @handleflags: desired handle flags for the desired GPIO line, such as
466 * %GPIOHANDLE_REQUEST_ACTIVE_LOW or %GPIOHANDLE_REQUEST_OPEN_DRAIN
467 * @eventflags: desired flags for the desired GPIO event line, such as
468 * %GPIOEVENT_REQUEST_RISING_EDGE or %GPIOEVENT_REQUEST_FALLING_EDGE
469 * @consumer_label: a desired consumer label for the selected GPIO line(s)
470 * such as "my-listener"
471 * @fd: after a successful %GPIO_GET_LINEEVENT_IOCTL operation, contains a
472 * valid anonymous file descriptor representing the request
474 * Note: This struct is part of ABI v1 and is deprecated.
475 * Use ABI v2 and &struct gpio_v2_line_request instead.
477 struct gpioevent_request {
481 char consumer_label[GPIO_MAX_NAME_SIZE];
488 #define GPIOEVENT_EVENT_RISING_EDGE 0x01
489 #define GPIOEVENT_EVENT_FALLING_EDGE 0x02
492 * struct gpioevent_data - The actual event being pushed to userspace
493 * @timestamp: best estimate of time of event occurrence, in nanoseconds
494 * @id: event identifier, one of %GPIOEVENT_EVENT_RISING_EDGE or
495 * %GPIOEVENT_EVENT_FALLING_EDGE
497 * Note: This struct is part of ABI v1 and is deprecated.
498 * Use ABI v2 and &struct gpio_v2_line_event instead.
500 struct gpioevent_data {
508 #define GPIO_GET_CHIPINFO_IOCTL _IOR(0xB4, 0x01, struct gpiochip_info)
509 #define GPIO_GET_LINEINFO_UNWATCH_IOCTL _IOWR(0xB4, 0x0C, __u32)
514 #define GPIO_V2_GET_LINEINFO_IOCTL _IOWR(0xB4, 0x05, struct gpio_v2_line_info)
515 #define GPIO_V2_GET_LINEINFO_WATCH_IOCTL _IOWR(0xB4, 0x06, struct gpio_v2_line_info)
516 #define GPIO_V2_GET_LINE_IOCTL _IOWR(0xB4, 0x07, struct gpio_v2_line_request)
517 #define GPIO_V2_LINE_SET_CONFIG_IOCTL _IOWR(0xB4, 0x0D, struct gpio_v2_line_config)
518 #define GPIO_V2_LINE_GET_VALUES_IOCTL _IOWR(0xB4, 0x0E, struct gpio_v2_line_values)
519 #define GPIO_V2_LINE_SET_VALUES_IOCTL _IOWR(0xB4, 0x0F, struct gpio_v2_line_values)
524 * These ioctl()s are deprecated. Use the v2 equivalent instead.
526 #define GPIO_GET_LINEINFO_IOCTL _IOWR(0xB4, 0x02, struct gpioline_info)
527 #define GPIO_GET_LINEHANDLE_IOCTL _IOWR(0xB4, 0x03, struct gpiohandle_request)
528 #define GPIO_GET_LINEEVENT_IOCTL _IOWR(0xB4, 0x04, struct gpioevent_request)
529 #define GPIOHANDLE_GET_LINE_VALUES_IOCTL _IOWR(0xB4, 0x08, struct gpiohandle_data)
530 #define GPIOHANDLE_SET_LINE_VALUES_IOCTL _IOWR(0xB4, 0x09, struct gpiohandle_data)
531 #define GPIOHANDLE_SET_CONFIG_IOCTL _IOWR(0xB4, 0x0A, struct gpiohandle_config)
532 #define GPIO_GET_LINEINFO_WATCH_IOCTL _IOWR(0xB4, 0x0B, struct gpioline_info)
534 #endif /* _UAPI_GPIO_H_ */