diff options
Diffstat (limited to 'include/uapi/linux/gpio.h')
| -rw-r--r-- | include/uapi/linux/gpio.h | 158 |
1 files changed, 86 insertions, 72 deletions
diff --git a/include/uapi/linux/gpio.h b/include/uapi/linux/gpio.h index 07865c601099..f7cb8ae87df7 100644 --- a/include/uapi/linux/gpio.h +++ b/include/uapi/linux/gpio.h @@ -1,4 +1,4 @@ -/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +/* SPDX-License-Identifier: GPL-2.0-only WITH Linux-syscall-note */ /* * <linux/gpio.h> - userspace ABI for the GPIO character devices * @@ -26,7 +26,7 @@ * 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 + * number, may be empty (i.e. label[0] == '\0') * @lines: number of GPIO lines on this chip */ struct gpiochip_info { @@ -65,6 +65,9 @@ struct gpiochip_info { * @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 + * @GPIO_V2_LINE_FLAG_EVENT_CLOCK_HTE: line events contain timestamps from + * the hardware timestamping engine (HTE) subsystem */ enum gpio_v2_line_flag { GPIO_V2_LINE_FLAG_USED = _BITULL(0), @@ -78,15 +81,17 @@ enum gpio_v2_line_flag { 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), + GPIO_V2_LINE_FLAG_EVENT_CLOCK_HTE = _BITULL(12), }; /** * 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. + * 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. + * gpio_v2_line_request.offsets */ struct gpio_v2_line_values { __aligned_u64 bits; @@ -98,7 +103,7 @@ struct gpio_v2_line_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 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, @@ -110,17 +115,17 @@ enum gpio_v2_line_attr_id { * 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, OR:ed + * @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 + * @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 + * 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; @@ -138,7 +143,7 @@ struct gpio_v2_line_attribute { * @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. + * gpio_v2_line_request.offsets */ struct gpio_v2_line_config_attribute { struct gpio_v2_line_attribute attr; @@ -147,12 +152,12 @@ struct gpio_v2_line_config_attribute { /** * 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, OR:ed together. This is the default for + * @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 + * @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 @@ -173,20 +178,19 @@ struct gpio_v2_line_config { * associated GPIO chip * @consumer: a desired consumer label for the selected GPIO lines such as * "my-bitbanged-relay" - * @config: requested configuration for the lines. + * @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 + * 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. + * 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 + * @fd: after a successful %GPIO_V2_GET_LINE_IOCTL operation, contains + * a valid anonymous file descriptor representing the request */ struct gpio_v2_line_request { __u32 offsets[GPIO_V2_LINES_MAX]; @@ -203,15 +207,16 @@ struct gpio_v2_line_request { * 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 + * 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 - * @flags: flags for the GPIO line, such as GPIO_V2_LINE_FLAG_ACTIVE_LOW, - * GPIO_V2_LINE_FLAG_OUTPUT etc, OR:ed together * @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 + * @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 */ @@ -244,7 +249,7 @@ enum gpio_v2_line_changed_type { * 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 + * @event_type: the type of change with a value from &enum * gpio_v2_line_changed_type * @padding: reserved for future use */ @@ -268,17 +273,25 @@ enum gpio_v2_line_event_id { /** * struct gpio_v2_line_event - The actual event being pushed to userspace - * @timestamp_ns: best estimate of time of event occurrence, in nanoseconds. - * 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. - * @id: event identifier with value from enum gpio_v2_line_event_id + * @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. + * + * If the %GPIO_V2_LINE_FLAG_EVENT_CLOCK_HTE flag is set then the + * @timestamp_ns is provided by the hardware timestamping engine (HTE) + * subsystem. */ struct gpio_v2_line_event { __aligned_u64 timestamp_ns; @@ -291,7 +304,7 @@ struct gpio_v2_line_event { }; /* - * ABI v1 + * ABI v1 * * This version of the ABI is deprecated. * Use the latest version of the ABI, defined above, instead. @@ -314,13 +327,13 @@ struct gpio_v2_line_event { * @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 + * 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 * - * This struct is part of ABI v1 and is deprecated. - * Use struct gpio_v2_line_info instead. + * Note: This struct is part of ABI v1 and is deprecated. + * Use ABI v2 and &struct gpio_v2_line_info instead. */ struct gpioline_info { __u32 line_offset; @@ -344,17 +357,18 @@ enum { * 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 + * @event_type: one of %GPIOLINE_CHANGED_REQUESTED, + * %GPIOLINE_CHANGED_RELEASED and %GPIOLINE_CHANGED_CONFIG + * @padding: reserved for future use * - * Note: struct gpioline_info embedded here has 32-bit alignment on its own, + * 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. * - * This struct is part of ABI v1 and is deprecated. - * Use struct gpio_v2_line_info_changed instead. + * Note: This struct is part of ABI v1 and is deprecated. + * Use ABI v2 and &struct gpio_v2_line_info_changed instead. */ struct gpioline_info_changed { struct gpioline_info info; @@ -378,25 +392,24 @@ struct gpioline_info_changed { * @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, OR:ed + * %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) + * @default_values: if the %GPIOHANDLE_REQUEST_OUTPUT is set for a requested + * line, this specifies the default output value, should be 0 (inactive) or + * 1 (active). Anything other than 0 or 1 will be interpreted as active. * @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 + * @fd: after a successful %GPIO_GET_LINEHANDLE_IOCTL operation, contains + * a valid anonymous file descriptor representing the request * - * This struct is part of ABI v1 and is deprecated. - * Use struct gpio_v2_line_request instead. + * Note: This struct is part of ABI v1 and is deprecated. + * Use ABI v2 and &struct gpio_v2_line_request instead. */ struct gpiohandle_request { __u32 lineoffsets[GPIOHANDLES_MAX]; @@ -410,15 +423,15 @@ struct gpiohandle_request { /** * 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, OR:ed + * %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) + * @default_values: if the %GPIOHANDLE_REQUEST_OUTPUT is set in flags, + * this specifies the default output value, should be 0 (inactive) or + * 1 (active). Anything other than 0 or 1 will be interpreted as active. * @padding: reserved for future use and should be zero filled * - * This struct is part of ABI v1 and is deprecated. - * Use struct gpio_v2_line_config instead. + * Note: This struct is part of ABI v1 and is deprecated. + * Use ABI v2 and &struct gpio_v2_line_config instead. */ struct gpiohandle_config { __u32 flags; @@ -430,10 +443,11 @@ struct gpiohandle_config { * 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 + * the desired target state. States are 0 (inactive) or 1 (active). + * When setting, anything other than 0 or 1 will be interpreted as active. * - * This struct is part of ABI v1 and is deprecated. - * Use struct gpio_v2_line_values instead. + * Note: This struct is part of ABI v1 and is deprecated. + * Use ABI v2 and &struct gpio_v2_line_values instead. */ struct gpiohandle_data { __u8 values[GPIOHANDLES_MAX]; @@ -449,17 +463,16 @@ struct gpiohandle_data { * @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 + * %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 + * %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 + * @fd: after a successful %GPIO_GET_LINEEVENT_IOCTL operation, contains a + * valid anonymous file descriptor representing the request * - * This struct is part of ABI v1 and is deprecated. - * Use struct gpio_v2_line_request instead. + * Note: This struct is part of ABI v1 and is deprecated. + * Use ABI v2 and &struct gpio_v2_line_request instead. */ struct gpioevent_request { __u32 lineoffset; @@ -469,7 +482,7 @@ struct gpioevent_request { int fd; }; -/** +/* * GPIO event types */ #define GPIOEVENT_EVENT_RISING_EDGE 0x01 @@ -478,10 +491,11 @@ struct gpioevent_request { /** * struct gpioevent_data - The actual event being pushed to userspace * @timestamp: best estimate of time of event occurrence, in nanoseconds - * @id: event identifier + * @id: event identifier, one of %GPIOEVENT_EVENT_RISING_EDGE or + * %GPIOEVENT_EVENT_FALLING_EDGE * - * This struct is part of ABI v1 and is deprecated. - * Use struct gpio_v2_line_event instead. + * Note: This struct is part of ABI v1 and is deprecated. + * Use ABI v2 and &struct gpio_v2_line_event instead. */ struct gpioevent_data { __u64 timestamp; |