xref: /freebsd/sys/sys/gpio.h (revision f6197f2bc05b5a8df260cbf55283fddf7c76fec4)
1 /* $NetBSD: gpio.h,v 1.7 2009/09/25 20:27:50 mbalmer Exp $ */
2 /*	$OpenBSD: gpio.h,v 1.7 2008/11/26 14:51:20 mbalmer Exp $	*/
3 /*-
4  * SPDX-License-Identifier: (BSD-2-Clause AND ISC)
5  *
6  * Copyright (c) 2009, Oleksandr Tymoshenko <gonzo@FreeBSD.org>
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice unmodified, this list of conditions, and the following
14  *    disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  *
31  */
32 
33 /*
34  * Copyright (c) 2009 Marc Balmer <marc@msys.ch>
35  * Copyright (c) 2004 Alexander Yurchenko <grange@openbsd.org>
36  *
37  * Permission to use, copy, modify, and distribute this software for any
38  * purpose with or without fee is hereby granted, provided that the above
39  * copyright notice and this permission notice appear in all copies.
40  *
41  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
42  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
43  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
44  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
45  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
46  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
47  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
48  */
49 
50 #ifndef __GPIO_H__
51 #define __GPIO_H__
52 
53 #include <sys/ioccom.h>
54 #if !defined(_KERNEL) && !defined(_STANDALONE)
55 #include <stdbool.h>
56 #endif
57 
58 /* GPIO pin states */
59 #define GPIO_PIN_LOW		0x00	/* low level (logical 0) */
60 #define GPIO_PIN_HIGH		0x01	/* high level (logical 1) */
61 
62 /* Max name length of a pin */
63 #define GPIOMAXNAME		64
64 
65 /* GPIO pin configuration flags */
66 #define GPIO_PIN_INPUT		0x00000001	/* input direction */
67 #define GPIO_PIN_OUTPUT		0x00000002	/* output direction */
68 #define GPIO_PIN_OPENDRAIN	0x00000004	/* open-drain output */
69 #define GPIO_PIN_PUSHPULL	0x00000008	/* push-pull output */
70 #define GPIO_PIN_TRISTATE	0x00000010	/* output disabled */
71 #define GPIO_PIN_PULLUP		0x00000020	/* internal pull-up enabled */
72 #define GPIO_PIN_PULLDOWN	0x00000040	/* internal pull-down enabled */
73 #define GPIO_PIN_INVIN		0x00000080	/* invert input */
74 #define GPIO_PIN_INVOUT		0x00000100	/* invert output */
75 #define GPIO_PIN_PULSATE	0x00000200	/* pulsate in hardware */
76 #define GPIO_PIN_PRESET_LOW	0x00000400	/* preset pin to high or */
77 #define GPIO_PIN_PRESET_HIGH	0x00000800	/* low before enabling output */
78 /* GPIO interrupt capabilities */
79 #define GPIO_INTR_NONE		0x00000000	/* no interrupt support */
80 #define GPIO_INTR_LEVEL_LOW	0x00010000	/* level trigger, low */
81 #define GPIO_INTR_LEVEL_HIGH	0x00020000	/* level trigger, high */
82 #define GPIO_INTR_EDGE_RISING	0x00040000	/* edge trigger, rising */
83 #define GPIO_INTR_EDGE_FALLING	0x00080000	/* edge trigger, falling */
84 #define GPIO_INTR_EDGE_BOTH	0x00100000	/* edge trigger, both */
85 #define GPIO_INTR_ATTACHED	0x00200000	/* interrupt attached to file */
86 #define GPIO_INTR_EDGE_MASK	(GPIO_INTR_EDGE_RISING | \
87 				GPIO_INTR_EDGE_FALLING | GPIO_INTR_EDGE_BOTH )
88 #define GPIO_INTR_MASK		(GPIO_INTR_LEVEL_LOW | GPIO_INTR_LEVEL_HIGH |  \
89 				GPIO_INTR_EDGE_MASK | GPIO_INTR_ATTACHED)
90 
91 struct gpio_pin {
92 	uint32_t gp_pin;			/* pin number */
93 	char gp_name[GPIOMAXNAME];		/* human-readable name */
94 	uint32_t gp_caps;			/* capabilities */
95 	uint32_t gp_flags;			/* current flags */
96 };
97 
98 /* GPIO pin request (read/write/toggle) */
99 struct gpio_req {
100 	uint32_t gp_pin;			/* pin number */
101 	uint32_t gp_value;			/* value */
102 };
103 
104 /*
105  * Reporting gpio pin-change per-event details to userland.
106  *
107  * When configured for detail reporting, each call to read(2) will return one or
108  * more of these structures (or will return EWOULDBLOCK in non-blocking IO mode
109  * when there are no new events to report).
110  */
111 struct gpio_event_detail {
112 	sbintime_t	gp_time;	/* Time of event */
113 	uint16_t	gp_pin;		/* Pin number */
114 	bool		gp_pinstate;	/* Pin state at time of event */
115 };
116 
117 /*
118  * Reporting gpio pin-change summary data to userland.
119  *
120  * When configured for summary reporting, each call to read(2) will return one
121  * or more of these structures (or will return EWOULDBLOCK in non-blocking IO
122  * mode when there are no new events to report).
123  */
124 struct gpio_event_summary {
125 	sbintime_t	gp_first_time;	/* Time of first event */
126 	sbintime_t	gp_last_time;	/* Time of last event */
127 	uint16_t	gp_pin;		/* Pin number */
128 	uint16_t	gp_count;	/* Event count */
129 	bool		gp_first_state;	/* Pin state at first event */
130 	bool		gp_last_state;	/* Pin state at last event */
131 };
132 
133 /*
134  * Configuring event reporting to userland.
135  *
136  * The default is to deliver gpio_event_detail reporting, with a default fifo
137  * size of 2 * number of pins belonging to the gpioc device instance.  To change
138  * it, you must use the GPIOCONFIGEVENTS ioctl before using GPIOSETCONFIG to
139  * configure reporting interrupt events on any pins.  This config is tracked on
140  * a per-open-descriptor basis.
141  */
142 enum {
143 	GPIO_EVENT_REPORT_DETAIL,	/* Report detail on each event */
144 	GPIO_EVENT_REPORT_SUMMARY,	/* Report summary of events */
145 };
146 struct gpio_event_config {
147 	uint32_t	gp_report_type; /* Detail or summary reporting */
148 	uint32_t	gp_fifo_size;	/* FIFO size (used for detail only) */
149 };
150 
151 /*
152  * gpio_access_32 / GPIOACCESS32
153  *
154  * Simultaneously read and/or change up to 32 adjacent pins.
155  * If the device cannot change the pins simultaneously, returns EOPNOTSUPP.
156  *
157  * This accesses an adjacent set of up to 32 pins starting at first_pin within
158  * the device's collection of pins.  How the hardware pins are mapped to the 32
159  * bits in the arguments is device-specific.  It is expected that lower-numbered
160  * pins in the device's number space map linearly to lower-ordered bits within
161  * the 32-bit words (i.e., bit 0 is first_pin, bit 1 is first_pin+1, etc).
162  * Other mappings are possible; know your device.
163  *
164  * Some devices may limit the value of first_pin to 0, or to multiples of 16 or
165  * 32 or some other hardware-specific number; to access pin 2 would require
166  * first_pin to be zero and then manipulate bit (1 << 2) in the 32-bit word.
167  * Invalid values in first_pin result in an EINVAL error return.
168  *
169  * The starting state of the pins is captured and stored in orig_pins, then the
170  * pins are set to ((starting_state & ~clear_pins) ^ change_pins).
171  *
172  *   Clear  Change  Hardware pin after call
173  *     0      0        No change
174  *     0      1        Opposite of current value
175  *     1      0        Cleared
176  *     1      1        Set
177  */
178 struct gpio_access_32 {
179 	uint32_t first_pin;	/* First pin in group of 32 adjacent */
180 	uint32_t clear_pins;	/* Pins are changed using: */
181 	uint32_t change_pins;	/* ((hwstate & ~clear_pins) ^ change_pins) */
182 	uint32_t orig_pins;	/* Returned hwstate of pins before change. */
183 };
184 
185 /*
186  * gpio_config_32 / GPIOCONFIG32
187  *
188  * Simultaneously configure up to 32 adjacent pins.  This is intended to change
189  * the configuration of all the pins simultaneously, such that pins configured
190  * for output all begin to drive the configured values simultaneously, but not
191  * all hardware can do that, so the driver "does the best it can" in this
192  * regard.  Notably unlike pin_access_32(), this does NOT fail if the pins
193  * cannot be atomically configured; it is expected that callers understand the
194  * hardware and have decided to live with any such limitations it may have.
195  *
196  * The pin_flags argument is an array of GPIO_PIN_xxxx flags.  If the array
197  * contains any GPIO_PIN_OUTPUT flags, the driver will manipulate the hardware
198  * such that all output pins become driven with the proper initial values
199  * simultaneously if it can.  The elements in the array map to pins in the same
200  * way that bits are mapped by pin_access_32(), and the same restrictions may
201  * apply.  For example, to configure pins 2 and 3 it may be necessary to set
202  * first_pin to zero and only populate pin_flags[2] and pin_flags[3].  If a
203  * given array entry doesn't contain GPIO_PIN_INPUT or GPIO_PIN_OUTPUT then no
204  * configuration is done for that pin.
205  *
206  * Some devices may limit the value of first_pin to 0, or to multiples of 16 or
207  * 32 or some other hardware-specific number.  Invalid values in first_pin or
208  * num_pins result in an error return with errno set to EINVAL.
209  *
210  * You cannot configure interrupts (userland pin-change notifications) with
211  * this function; each interrupt pin must be individually configured.
212  */
213 struct gpio_config_32 {
214 	uint32_t first_pin;
215 	uint32_t num_pins;
216 	uint32_t pin_flags[32];
217 };
218 
219 /*
220  * ioctls
221  */
222 #define GPIOMAXPIN		_IOR('G', 0, int)
223 #define	GPIOGETCONFIG		_IOWR('G', 1, struct gpio_pin)
224 #define	GPIOSETCONFIG		_IOW('G', 2, struct gpio_pin)
225 #define	GPIOGET			_IOWR('G', 3, struct gpio_req)
226 #define	GPIOSET			_IOW('G', 4, struct gpio_req)
227 #define	GPIOTOGGLE		_IOWR('G', 5, struct gpio_req)
228 #define	GPIOSETNAME		_IOW('G', 6, struct gpio_pin)
229 #define	GPIOACCESS32		_IOWR('G', 7, struct gpio_access_32)
230 #define	GPIOCONFIG32		_IOW('G', 8, struct gpio_config_32)
231 #define	GPIOCONFIGEVENTS	_IOW('G', 9, struct gpio_event_config)
232 
233 #endif /* __GPIO_H__ */
234