xref: /netbsd-src/sys/dev/gpio/gpio.c (revision b1c86f5f087524e68db12794ee9c3e3da1ab17a0)
1 /* $NetBSD: gpio.c,v 1.33 2010/04/25 11:23:34 ad Exp $ */
2 /*	$OpenBSD: gpio.c,v 1.6 2006/01/14 12:33:49 grange Exp $	*/
3 
4 /*
5  * Copyright (c) 2008, 2009, 2010 Marc Balmer <marc@msys.ch>
6  * Copyright (c) 2004, 2006 Alexander Yurchenko <grange@openbsd.org>
7  *
8  * Permission to use, copy, modify, and distribute this software for any
9  * purpose with or without fee is hereby granted, provided that the above
10  * copyright notice and this permission notice appear in all copies.
11  *
12  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
13  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
14  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
15  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
16  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
17  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
18  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
19  */
20 
21 #include <sys/cdefs.h>
22 __KERNEL_RCSID(0, "$NetBSD: gpio.c,v 1.33 2010/04/25 11:23:34 ad Exp $");
23 
24 /*
25  * General Purpose Input/Output framework.
26  */
27 
28 #include <sys/param.h>
29 #include <sys/systm.h>
30 #include <sys/conf.h>
31 #include <sys/device.h>
32 #include <sys/fcntl.h>
33 #include <sys/ioctl.h>
34 #include <sys/gpio.h>
35 #include <sys/vnode.h>
36 #include <sys/kmem.h>
37 #include <sys/queue.h>
38 #include <sys/kauth.h>
39 
40 #include <dev/gpio/gpiovar.h>
41 
42 #include "locators.h"
43 
44 #ifdef GPIO_DEBUG
45 #define DPRINTFN(n, x)	do { if (gpiodebug > (n)) printf x; } while (0)
46 int gpiodebug = 0;
47 #else
48 #define DPRINTFN(n, x)
49 #endif
50 #define DPRINTF(x)	DPRINTFN(0, x)
51 
52 struct gpio_softc {
53 	device_t		 sc_dev;
54 
55 	gpio_chipset_tag_t	 sc_gc;		/* GPIO controller */
56 	gpio_pin_t		*sc_pins;	/* pins array */
57 	int			 sc_npins;	/* number of pins */
58 
59 	int			 sc_opened;
60 	LIST_HEAD(, gpio_dev)	 sc_devs;	/* devices */
61 	LIST_HEAD(, gpio_name)	 sc_names;	/* named pins */
62 };
63 
64 int	gpio_match(device_t, cfdata_t, void *);
65 int	gpio_submatch(device_t, cfdata_t, const int *, void *);
66 void	gpio_attach(device_t, device_t, void *);
67 int	gpio_rescan(device_t, const char *, const int *);
68 void	gpio_childdetached(device_t, device_t);
69 bool	gpio_resume(device_t, const pmf_qual_t *);
70 int	gpio_detach(device_t, int);
71 int	gpio_search(device_t, cfdata_t, const int *, void *);
72 int	gpio_print(void *, const char *);
73 int	gpio_pinbyname(struct gpio_softc *, char *);
74 
75 /* Old API */
76 int	gpio_ioctl_oapi(struct gpio_softc *, u_long, void *, int, kauth_cred_t);
77 
78 CFATTACH_DECL3_NEW(gpio, sizeof(struct gpio_softc),
79     gpio_match, gpio_attach, gpio_detach, NULL, gpio_rescan,
80     gpio_childdetached, DVF_DETACH_SHUTDOWN);
81 
82 dev_type_open(gpioopen);
83 dev_type_close(gpioclose);
84 dev_type_ioctl(gpioioctl);
85 
86 const struct cdevsw gpio_cdevsw = {
87 	gpioopen, gpioclose, noread, nowrite, gpioioctl,
88 	nostop, notty, nopoll, nommap, nokqfilter, D_OTHER,
89 };
90 
91 extern struct cfdriver gpio_cd;
92 
93 int
94 gpio_match(device_t parent, cfdata_t cf, void *aux)
95 {
96 	return 1;
97 }
98 
99 int
100 gpio_submatch(device_t parent, cfdata_t cf, const int *ip, void *aux)
101 {
102 	struct gpio_attach_args *ga = aux;
103 
104 	if (ga->ga_offset == -1)
105 		return 0;
106 
107 	return strcmp(ga->ga_dvname, cf->cf_name) == 0;
108 }
109 
110 bool
111 gpio_resume(device_t self, const pmf_qual_t *qual)
112 {
113 	struct gpio_softc *sc = device_private(self);
114 	int pin;
115 
116 	for (pin = 0; pin < sc->sc_npins; pin++) {
117 		gpiobus_pin_ctl(sc->sc_gc, pin, sc->sc_pins[pin].pin_flags);
118 		gpiobus_pin_write(sc->sc_gc, pin, sc->sc_pins[pin].pin_state);
119 	}
120 	return true;
121 }
122 
123 void
124 gpio_childdetached(device_t self, device_t child)
125 {
126 	/* gpio(4) keeps no references to its children, so do nothing. */
127 }
128 
129 int
130 gpio_rescan(device_t self, const char *ifattr, const int *locators)
131 {
132 	struct gpio_softc *sc = device_private(self);
133 
134 	config_search_loc(gpio_search, self, ifattr, locators, sc);
135 
136 	return 0;
137 }
138 
139 void
140 gpio_attach(device_t parent, device_t self, void *aux)
141 {
142 	struct gpio_softc *sc = device_private(self);
143 	struct gpiobus_attach_args *gba = aux;
144 
145 	sc->sc_dev = self;
146 	sc->sc_gc = gba->gba_gc;
147 	sc->sc_pins = gba->gba_pins;
148 	sc->sc_npins = gba->gba_npins;
149 
150 	printf(": %d pins\n", sc->sc_npins);
151 
152 	if (!pmf_device_register(self, NULL, gpio_resume))
153 		aprint_error_dev(self, "couldn't establish power handler\n");
154 
155 	/*
156 	 * Attach all devices that can be connected to the GPIO pins
157 	 * described in the kernel configuration file.
158 	 */
159 	gpio_rescan(self, "gpio", NULL);
160 }
161 
162 int
163 gpio_detach(device_t self, int flags)
164 {
165 	int rc;
166 
167 	if ((rc = config_detach_children(self, flags)) != 0)
168 		return rc;
169 
170 #if 0
171 	int maj, mn;
172 
173 	/* Locate the major number */
174 	for (maj = 0; maj < nchrdev; maj++)
175 		if (cdevsw[maj].d_open == gpioopen)
176 			break;
177 
178 	/* Nuke the vnodes for any open instances (calls close) */
179 	mn = device_unit(self);
180 	vdevgone(maj, mn, mn, VCHR);
181 #endif
182 	return 0;
183 }
184 
185 int
186 gpio_search(device_t parent, cfdata_t cf, const int *ldesc, void *aux)
187 {
188 	struct gpio_attach_args ga;
189 
190 	ga.ga_gpio = aux;
191 	ga.ga_offset = cf->cf_loc[GPIOCF_OFFSET];
192 	ga.ga_mask = cf->cf_loc[GPIOCF_MASK];
193 
194 	if (config_match(parent, cf, &ga) > 0)
195 		config_attach(parent, cf, &ga, gpio_print);
196 
197 	return 0;
198 }
199 
200 int
201 gpio_print(void *aux, const char *pnp)
202 {
203 	struct gpio_attach_args *ga = aux;
204 	int i;
205 
206 	printf(" pins");
207 	for (i = 0; i < 32; i++)
208 		if (ga->ga_mask & (1 << i))
209 			printf(" %d", ga->ga_offset + i);
210 
211 	return UNCONF;
212 }
213 
214 int
215 gpiobus_print(void *aux, const char *pnp)
216 {
217 #if 0
218 	struct gpiobus_attach_args *gba = aux;
219 #endif
220 	if (pnp != NULL)
221 		aprint_normal("gpiobus at %s", pnp);
222 
223 	return UNCONF;
224 }
225 
226 /* return 1 if all pins can be mapped, 0 if not */
227 int
228 gpio_pin_can_map(void *gpio, int offset, u_int32_t mask)
229 {
230 	struct gpio_softc *sc = gpio;
231 	int npins, pin, i;
232 
233 	npins = gpio_npins(mask);
234 	if (npins > sc->sc_npins)
235 		return 0;
236 
237 	for (npins = 0, i = 0; i < 32; i++)
238 		if (mask & (1 << i)) {
239 			pin = offset + i;
240 			if (pin < 0 || pin >= sc->sc_npins)
241 				return 0;
242 			if (sc->sc_pins[pin].pin_mapped)
243 				return 0;
244 		}
245 
246 	return 1;
247 }
248 
249 int
250 gpio_pin_map(void *gpio, int offset, u_int32_t mask, struct gpio_pinmap *map)
251 {
252 	struct gpio_softc *sc = gpio;
253 	int npins, pin, i;
254 
255 	npins = gpio_npins(mask);
256 	if (npins > sc->sc_npins)
257 		return 1;
258 
259 	for (npins = 0, i = 0; i < 32; i++)
260 		if (mask & (1 << i)) {
261 			pin = offset + i;
262 			if (pin < 0 || pin >= sc->sc_npins)
263 				return 1;
264 			if (sc->sc_pins[pin].pin_mapped)
265 				return 1;
266 			sc->sc_pins[pin].pin_mapped = 1;
267 			map->pm_map[npins++] = pin;
268 		}
269 	map->pm_size = npins;
270 
271 	return 0;
272 }
273 
274 void
275 gpio_pin_unmap(void *gpio, struct gpio_pinmap *map)
276 {
277 	struct gpio_softc *sc = gpio;
278 	int pin, i;
279 
280 	for (i = 0; i < map->pm_size; i++) {
281 		pin = map->pm_map[i];
282 		sc->sc_pins[pin].pin_mapped = 0;
283 	}
284 }
285 
286 int
287 gpio_pin_read(void *gpio, struct gpio_pinmap *map, int pin)
288 {
289 	struct gpio_softc *sc = gpio;
290 
291 	return gpiobus_pin_read(sc->sc_gc, map->pm_map[pin]);
292 }
293 
294 void
295 gpio_pin_write(void *gpio, struct gpio_pinmap *map, int pin, int value)
296 {
297 	struct gpio_softc *sc = gpio;
298 
299 	gpiobus_pin_write(sc->sc_gc, map->pm_map[pin], value);
300 	sc->sc_pins[map->pm_map[pin]].pin_state = value;
301 }
302 
303 void
304 gpio_pin_ctl(void *gpio, struct gpio_pinmap *map, int pin, int flags)
305 {
306 	struct gpio_softc *sc = gpio;
307 
308 	return gpiobus_pin_ctl(sc->sc_gc, map->pm_map[pin], flags);
309 }
310 
311 int
312 gpio_pin_caps(void *gpio, struct gpio_pinmap *map, int pin)
313 {
314 	struct gpio_softc *sc = gpio;
315 
316 	return sc->sc_pins[map->pm_map[pin]].pin_caps;
317 }
318 
319 int
320 gpio_npins(u_int32_t mask)
321 {
322 	int npins, i;
323 
324 	for (npins = 0, i = 0; i < 32; i++)
325 		if (mask & (1 << i))
326 			npins++;
327 
328 	return npins;
329 }
330 
331 int
332 gpioopen(dev_t dev, int flag, int mode, struct lwp *l)
333 {
334 	struct gpio_softc *sc;
335 	int ret;
336 
337 	sc = device_lookup_private(&gpio_cd, minor(dev));
338 	if (sc == NULL)
339 		return ENXIO;
340 	DPRINTF(("%s: opening\n", device_xname(sc->sc_dev)));
341 	if (sc->sc_opened) {
342 		DPRINTF(("%s: already opened\n", device_xname(sc->sc_dev)));
343 		return EBUSY;
344 	}
345 
346 	if ((ret = gpiobus_open(sc->sc_gc, sc->sc_dev))) {
347 		DPRINTF(("%s: gpiobus_open returned %d\n",
348 		    device_xname(sc->sc_dev),
349 		    ret));
350 		return ret;
351 	}
352 
353 	sc->sc_opened = 1;
354 
355 	return 0;
356 }
357 
358 int
359 gpioclose(dev_t dev, int flag, int mode, struct lwp *l)
360 {
361 	struct gpio_softc *sc;
362 
363 	sc = device_lookup_private(&gpio_cd, minor(dev));
364 	DPRINTF(("%s: closing\n", device_xname(sc->sc_dev)));
365 	gpiobus_close(sc->sc_gc, sc->sc_dev);
366 	sc->sc_opened = 0;
367 
368 	return 0;
369 }
370 
371 int
372 gpio_pinbyname(struct gpio_softc *sc, char *gp_name)
373 {
374         struct gpio_name *nm;
375 
376         LIST_FOREACH(nm, &sc->sc_names, gp_next)
377                 if (!strcmp(nm->gp_name, gp_name))
378                         return nm->gp_pin;
379         return -1;
380 }
381 
382 int
383 gpioioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
384 {
385 	struct gpio_softc *sc;
386 	gpio_chipset_tag_t gc;
387 	struct gpio_info *info;
388 	struct gpio_attach *attach;
389 	struct gpio_attach_args ga;
390 	struct gpio_dev *gdev;
391 	struct gpio_req *req;
392 	struct gpio_name *nm;
393 	struct gpio_set *set;
394 	device_t dv;
395 	cfdata_t cf;
396 	kauth_cred_t cred;
397 	int locs[GPIOCF_NLOCS];
398 	int pin, value, flags, npins;
399 
400 	sc = device_lookup_private(&gpio_cd, minor(dev));
401 	gc = sc->sc_gc;
402 
403 	if (cmd != GPIOINFO && !device_is_active(sc->sc_dev)) {
404 		DPRINTF(("%s: device is not active\n",
405 		    device_xname(sc->sc_dev)));
406 		return EBUSY;
407 	}
408 
409 	cred = kauth_cred_get();
410 
411 	switch (cmd) {
412 	case GPIOINFO:
413 		info = (struct gpio_info *)data;
414 		if (!kauth_authorize_device(cred, KAUTH_DEVICE_GPIO_PINSET,
415 		    NULL, NULL, NULL, NULL))
416 			info->gpio_npins = sc->sc_npins;
417 		else {
418 			for (pin = npins = 0; pin < sc->sc_npins; pin++)
419 				if (sc->sc_pins[pin].pin_flags & GPIO_PIN_SET)
420 					++npins;
421 			info->gpio_npins = npins;
422 		}
423 		break;
424 	case GPIOREAD:
425 		req = (struct gpio_req *)data;
426 
427 		if (req->gp_name[0] != '\0') {
428 			pin = gpio_pinbyname(sc, req->gp_name);
429 			if (pin == -1)
430 				return EINVAL;
431 		} else
432 			pin = req->gp_pin;
433 
434 		if (pin < 0 || pin >= sc->sc_npins)
435 			return EINVAL;
436 
437 		if (!(sc->sc_pins[pin].pin_flags & GPIO_PIN_SET) &&
438 		    kauth_authorize_device(cred, KAUTH_DEVICE_GPIO_PINSET,
439 		    NULL, NULL, NULL, NULL))
440 			return EPERM;
441 
442 		/* return read value */
443 		req->gp_value = gpiobus_pin_read(gc, pin);
444 		break;
445 	case GPIOWRITE:
446 		if ((flag & FWRITE) == 0)
447 			return EBADF;
448 
449 		req = (struct gpio_req *)data;
450 
451 		if (req->gp_name[0] != '\0') {
452 			pin = gpio_pinbyname(sc, req->gp_name);
453 			if (pin == -1)
454 				return EINVAL;
455 		} else
456 			pin = req->gp_pin;
457 
458 		if (pin < 0 || pin >= sc->sc_npins)
459 			return EINVAL;
460 
461 		if (sc->sc_pins[pin].pin_mapped)
462 			return EBUSY;
463 
464 		if (!(sc->sc_pins[pin].pin_flags & GPIO_PIN_SET) &&
465 		    kauth_authorize_device(cred, KAUTH_DEVICE_GPIO_PINSET,
466 		    NULL, NULL, NULL, NULL))
467 			return EPERM;
468 
469 		value = req->gp_value;
470 		if (value != GPIO_PIN_LOW && value != GPIO_PIN_HIGH)
471 			return EINVAL;
472 
473 		gpiobus_pin_write(gc, pin, value);
474 		/* return old value */
475 		req->gp_value = sc->sc_pins[pin].pin_state;
476 		/* update current value */
477 		sc->sc_pins[pin].pin_state = value;
478 		break;
479 	case GPIOTOGGLE:
480 		if ((flag & FWRITE) == 0)
481 			return EBADF;
482 
483 		req = (struct gpio_req *)data;
484 
485 		if (req->gp_name[0] != '\0') {
486 			pin = gpio_pinbyname(sc, req->gp_name);
487 			if (pin == -1)
488 				return EINVAL;
489 		} else
490 			pin = req->gp_pin;
491 
492 		if (pin < 0 || pin >= sc->sc_npins)
493 			return EINVAL;
494 
495 		if (sc->sc_pins[pin].pin_mapped)
496 			return EBUSY;
497 
498 		if (!(sc->sc_pins[pin].pin_flags & GPIO_PIN_SET) &&
499 		    kauth_authorize_device(cred, KAUTH_DEVICE_GPIO_PINSET,
500 		    NULL, NULL, NULL, NULL))
501 			return EPERM;
502 
503 		value = (sc->sc_pins[pin].pin_state == GPIO_PIN_LOW ?
504 		    GPIO_PIN_HIGH : GPIO_PIN_LOW);
505 		gpiobus_pin_write(gc, pin, value);
506 		/* return old value */
507 		req->gp_value = sc->sc_pins[pin].pin_state;
508 		/* update current value */
509 		sc->sc_pins[pin].pin_state = value;
510 		break;
511 	case GPIOATTACH:
512 		if (kauth_authorize_device(cred, KAUTH_DEVICE_GPIO_PINSET,
513 		    NULL, NULL, NULL, NULL))
514 			return EPERM;
515 
516 		attach = (struct gpio_attach *)data;
517 
518 		/* do not try to attach if the pins are already mapped */
519 		if (!gpio_pin_can_map(sc, attach->ga_offset, attach->ga_mask))
520 			return EBUSY;
521 
522 		ga.ga_gpio = sc;
523 		ga.ga_dvname = attach->ga_dvname;
524 		ga.ga_offset = attach->ga_offset;
525 		ga.ga_mask = attach->ga_mask;
526 		DPRINTF(("%s: attach %s with offset %d and mask 0x%02x\n",
527 		    device_xname(sc->sc_dev), ga.ga_dvname, ga.ga_offset,
528 		    ga.ga_mask));
529 
530 		locs[GPIOCF_OFFSET] = ga.ga_offset;
531 		locs[GPIOCF_MASK] = ga.ga_mask;
532 
533 		cf = config_search_loc(NULL, sc->sc_dev, "gpio", locs, &ga);
534 		if (cf != NULL) {
535 			dv = config_attach_loc(sc->sc_dev, cf, locs, &ga,
536 			    gpiobus_print);
537 			if (dv != NULL) {
538 				gdev = kmem_alloc(sizeof(struct gpio_dev),
539 				    KM_SLEEP);
540 				gdev->sc_dev = dv;
541 				LIST_INSERT_HEAD(&sc->sc_devs, gdev, sc_next);
542 			} else
543 				return EINVAL;
544 		} else
545 			return EINVAL;
546 		break;
547 	case GPIODETACH:
548 		if (kauth_authorize_device(cred, KAUTH_DEVICE_GPIO_PINSET,
549 		    NULL, NULL, NULL, NULL))
550 			return EPERM;
551 
552 		attach = (struct gpio_attach *)data;
553 		LIST_FOREACH(gdev, &sc->sc_devs, sc_next) {
554 			if (strcmp(device_xname(gdev->sc_dev),
555 			    attach->ga_dvname) == 0) {
556 				if (config_detach(gdev->sc_dev, 0) == 0) {
557 					LIST_REMOVE(gdev, sc_next);
558 					kmem_free(gdev,
559 					    sizeof(struct gpio_dev));
560 					return 0;
561 				}
562 				break;
563 			}
564 		}
565 		return EINVAL;
566 		break;
567 	case GPIOSET:
568 		if (kauth_authorize_device(cred, KAUTH_DEVICE_GPIO_PINSET,
569 		    NULL, NULL, NULL, NULL))
570 			return EPERM;
571 
572 		set = (struct gpio_set *)data;
573 
574 		if (set->gp_name[0] != '\0') {
575 			pin = gpio_pinbyname(sc, set->gp_name);
576 			if (pin == -1)
577 				return EINVAL;
578 		} else
579 			pin = set->gp_pin;
580 		if (pin < 0 || pin >= sc->sc_npins)
581 			return EINVAL;
582 		flags = set->gp_flags;
583 
584 		/* check that the controller supports all requested flags */
585 		if ((flags & sc->sc_pins[pin].pin_caps) != flags)
586 			return ENODEV;
587 		flags = set->gp_flags | GPIO_PIN_SET;
588 
589 		set->gp_caps = sc->sc_pins[pin].pin_caps;
590 		/* return old value */
591 		set->gp_flags = sc->sc_pins[pin].pin_flags;
592 		if (flags > 0) {
593 			gpiobus_pin_ctl(gc, pin, flags);
594 			/* update current value */
595 			sc->sc_pins[pin].pin_flags = flags;
596 		}
597 
598 		/* rename pin or new pin? */
599 		if (set->gp_name2[0] != '\0') {
600 			struct gpio_name *gnm;
601 
602 			gnm = NULL;
603 			LIST_FOREACH(nm, &sc->sc_names, gp_next) {
604 				if (!strcmp(nm->gp_name, set->gp_name2) &&
605 				    nm->gp_pin != pin)
606 					return EINVAL;	/* duplicate name */
607 				if (nm->gp_pin == pin)
608 					gnm = nm;
609 			}
610 			if (gnm != NULL)
611 				strlcpy(gnm->gp_name, set->gp_name2,
612 				    sizeof(gnm->gp_name));
613 			else  {
614 				nm = kmem_alloc(sizeof(struct gpio_name),
615 				    KM_SLEEP);
616 				strlcpy(nm->gp_name, set->gp_name2,
617 				    sizeof(nm->gp_name));
618 				nm->gp_pin = set->gp_pin;
619 				LIST_INSERT_HEAD(&sc->sc_names, nm, gp_next);
620 			}
621 		}
622 		break;
623 	case GPIOUNSET:
624 		if (kauth_authorize_device(cred, KAUTH_DEVICE_GPIO_PINSET,
625 		    NULL, NULL, NULL, NULL))
626 			return EPERM;
627 
628 		set = (struct gpio_set *)data;
629 		if (set->gp_name[0] != '\0') {
630 			pin = gpio_pinbyname(sc, set->gp_name);
631 			if (pin == -1)
632 				return EINVAL;
633 		} else
634 			pin = set->gp_pin;
635 
636 		if (pin < 0 || pin >= sc->sc_npins)
637 			return EINVAL;
638 		if (sc->sc_pins[pin].pin_mapped)
639 			return EBUSY;
640 		if (!(sc->sc_pins[pin].pin_flags & GPIO_PIN_SET))
641 			return EINVAL;
642 
643 		LIST_FOREACH(nm, &sc->sc_names, gp_next) {
644 			if (nm->gp_pin == pin) {
645 				LIST_REMOVE(nm, gp_next);
646 				kmem_free(nm, sizeof(struct gpio_name));
647 				break;
648 			}
649 		}
650 		sc->sc_pins[pin].pin_flags &= ~GPIO_PIN_SET;
651 		break;
652 	default:
653 		/* Try the old API */
654 		DPRINTF(("%s: trying the old API\n", device_xname(sc->sc_dev)));
655 		return gpio_ioctl_oapi(sc, cmd, data, flag, cred);
656 	}
657 	return 0;
658 }
659 
660 int
661 gpio_ioctl_oapi(struct gpio_softc *sc, u_long cmd, void *data, int flag,
662     kauth_cred_t cred)
663 {
664 	gpio_chipset_tag_t gc;
665 	struct gpio_pin_op *op;
666 	struct gpio_pin_ctl *ctl;
667 	int pin, value, flags;
668 
669 	gc = sc->sc_gc;
670 
671 	switch (cmd) {
672 	case GPIOPINREAD:
673 		op = (struct gpio_pin_op *)data;
674 
675 		pin = op->gp_pin;
676 
677 		if (pin < 0 || pin >= sc->sc_npins)
678 			return EINVAL;
679 
680 		if (!(sc->sc_pins[pin].pin_flags & GPIO_PIN_SET) &&
681 		    kauth_authorize_device(cred, KAUTH_DEVICE_GPIO_PINSET,
682 		    NULL, NULL, NULL, NULL))
683 			return EPERM;
684 
685 		/* return read value */
686 		op->gp_value = gpiobus_pin_read(gc, pin);
687 		break;
688 	case GPIOPINWRITE:
689 		if ((flag & FWRITE) == 0)
690 			return EBADF;
691 
692 		op = (struct gpio_pin_op *)data;
693 
694 		pin = op->gp_pin;
695 
696 		if (pin < 0 || pin >= sc->sc_npins)
697 			return EINVAL;
698 
699 		if (sc->sc_pins[pin].pin_mapped)
700 			return EBUSY;
701 
702 		if (!(sc->sc_pins[pin].pin_flags & GPIO_PIN_SET) &&
703 		    kauth_authorize_device(cred, KAUTH_DEVICE_GPIO_PINSET,
704 		    NULL, NULL, NULL, NULL))
705 			return EPERM;
706 
707 		value = op->gp_value;
708 		if (value != GPIO_PIN_LOW && value != GPIO_PIN_HIGH)
709 			return EINVAL;
710 
711 		gpiobus_pin_write(gc, pin, value);
712 		/* return old value */
713 		op->gp_value = sc->sc_pins[pin].pin_state;
714 		/* update current value */
715 		sc->sc_pins[pin].pin_state = value;
716 		break;
717 	case GPIOPINTOGGLE:
718 		if ((flag & FWRITE) == 0)
719 			return EBADF;
720 
721 		op = (struct gpio_pin_op *)data;
722 
723 		pin = op->gp_pin;
724 
725 		if (pin < 0 || pin >= sc->sc_npins)
726 			return EINVAL;
727 
728 		if (sc->sc_pins[pin].pin_mapped)
729 			return EBUSY;
730 
731 		if (!(sc->sc_pins[pin].pin_flags & GPIO_PIN_SET) &&
732 		    kauth_authorize_device(cred, KAUTH_DEVICE_GPIO_PINSET,
733 		    NULL, NULL, NULL, NULL))
734 			return EPERM;
735 
736 		value = (sc->sc_pins[pin].pin_state == GPIO_PIN_LOW ?
737 		    GPIO_PIN_HIGH : GPIO_PIN_LOW);
738 		gpiobus_pin_write(gc, pin, value);
739 		/* return old value */
740 		op->gp_value = sc->sc_pins[pin].pin_state;
741 		/* update current value */
742 		sc->sc_pins[pin].pin_state = value;
743 		break;
744 	case GPIOPINCTL:
745 		ctl = (struct gpio_pin_ctl *) data;
746 
747 		if (kauth_authorize_device(cred, KAUTH_DEVICE_GPIO_PINSET,
748 		    NULL, NULL, NULL, NULL))
749 			return EPERM;
750 
751 		pin = ctl->gp_pin;
752 
753 		if (pin < 0 || pin >= sc->sc_npins)
754 			return EINVAL;
755 		if (sc->sc_pins[pin].pin_mapped)
756 			return EBUSY;
757 		flags = ctl->gp_flags;
758 
759 		/* check that the controller supports all requested flags */
760 		if ((flags & sc->sc_pins[pin].pin_caps) != flags)
761 			return ENODEV;
762 
763 		ctl->gp_caps = sc->sc_pins[pin].pin_caps;
764 		/* return old value */
765 		ctl->gp_flags = sc->sc_pins[pin].pin_flags;
766 		if (flags > 0) {
767 			gpiobus_pin_ctl(gc, pin, flags);
768 			/* update current value */
769 			sc->sc_pins[pin].pin_flags = flags;
770 		}
771 		break;
772 	default:
773 		return ENOTTY;
774 	}
775 	return 0;
776 }
777