xref: /freebsd/sys/dev/gpio/gpiobus.c (revision 732a02b4e77866604a120a275c082bb6221bd2ff)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2009 Oleksandr Tymoshenko <gonzo@freebsd.org>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/bus.h>
35 #include <sys/gpio.h>
36 #ifdef INTRNG
37 #include <sys/intr.h>
38 #endif
39 #include <sys/kernel.h>
40 #include <sys/malloc.h>
41 #include <sys/module.h>
42 
43 #include <dev/gpio/gpiobusvar.h>
44 
45 #include "gpiobus_if.h"
46 
47 #undef GPIOBUS_DEBUG
48 #ifdef GPIOBUS_DEBUG
49 #define	dprintf printf
50 #else
51 #define	dprintf(x, arg...)
52 #endif
53 
54 static void gpiobus_print_pins(struct gpiobus_ivar *, char *, size_t);
55 static int gpiobus_parse_pins(struct gpiobus_softc *, device_t, int);
56 static int gpiobus_probe(device_t);
57 static int gpiobus_attach(device_t);
58 static int gpiobus_detach(device_t);
59 static int gpiobus_suspend(device_t);
60 static int gpiobus_resume(device_t);
61 static void gpiobus_probe_nomatch(device_t, device_t);
62 static int gpiobus_print_child(device_t, device_t);
63 static int gpiobus_child_location_str(device_t, device_t, char *, size_t);
64 static int gpiobus_child_pnpinfo_str(device_t, device_t, char *, size_t);
65 static device_t gpiobus_add_child(device_t, u_int, const char *, int);
66 static void gpiobus_hinted_child(device_t, const char *, int);
67 
68 /*
69  * GPIOBUS interface
70  */
71 static int gpiobus_acquire_bus(device_t, device_t, int);
72 static void gpiobus_release_bus(device_t, device_t);
73 static int gpiobus_pin_setflags(device_t, device_t, uint32_t, uint32_t);
74 static int gpiobus_pin_getflags(device_t, device_t, uint32_t, uint32_t*);
75 static int gpiobus_pin_getcaps(device_t, device_t, uint32_t, uint32_t*);
76 static int gpiobus_pin_set(device_t, device_t, uint32_t, unsigned int);
77 static int gpiobus_pin_get(device_t, device_t, uint32_t, unsigned int*);
78 static int gpiobus_pin_toggle(device_t, device_t, uint32_t);
79 
80 /*
81  * gpiobus_pin flags
82  *  The flags in struct gpiobus_pin are not related to the flags used by the
83  *  low-level controller driver in struct gpio_pin.  Currently, only pins
84  *  acquired via FDT data have gpiobus_pin.flags set, sourced from the flags in
85  *  the FDT properties.  In theory, these flags are defined per-platform.  In
86  *  practice they are always the flags from the dt-bindings/gpio/gpio.h file.
87  *  The only one of those flags we currently support is for handling active-low
88  *  pins, so we just define that flag here instead of including a GPL'd header.
89  */
90 #define	GPIO_ACTIVE_LOW 1
91 
92 /*
93  * XXX -> Move me to better place - gpio_subr.c?
94  * Also, this function must be changed when interrupt configuration
95  * data will be moved into struct resource.
96  */
97 #ifdef INTRNG
98 
99 struct resource *
100 gpio_alloc_intr_resource(device_t consumer_dev, int *rid, u_int alloc_flags,
101     gpio_pin_t pin, uint32_t intr_mode)
102 {
103 	u_int irq;
104 	struct intr_map_data_gpio *gpio_data;
105 	struct resource *res;
106 
107 	gpio_data = (struct intr_map_data_gpio *)intr_alloc_map_data(
108 	    INTR_MAP_DATA_GPIO, sizeof(*gpio_data), M_WAITOK | M_ZERO);
109 	gpio_data->gpio_pin_num = pin->pin;
110 	gpio_data->gpio_pin_flags = pin->flags;
111 	gpio_data->gpio_intr_mode = intr_mode;
112 
113 	irq = intr_map_irq(pin->dev, 0, (struct intr_map_data *)gpio_data);
114 	res = bus_alloc_resource(consumer_dev, SYS_RES_IRQ, rid, irq, irq, 1,
115 	    alloc_flags);
116 	if (res == NULL) {
117 		intr_free_intr_map_data((struct intr_map_data *)gpio_data);
118 		return (NULL);
119 	}
120 	rman_set_virtual(res, gpio_data);
121 	return (res);
122 }
123 #else
124 struct resource *
125 gpio_alloc_intr_resource(device_t consumer_dev, int *rid, u_int alloc_flags,
126     gpio_pin_t pin, uint32_t intr_mode)
127 {
128 
129 	return (NULL);
130 }
131 #endif
132 
133 int
134 gpio_check_flags(uint32_t caps, uint32_t flags)
135 {
136 
137 	/* Filter unwanted flags. */
138 	flags &= caps;
139 
140 	/* Cannot mix input/output together. */
141 	if (flags & GPIO_PIN_INPUT && flags & GPIO_PIN_OUTPUT)
142 		return (EINVAL);
143 	/* Cannot mix pull-up/pull-down together. */
144 	if (flags & GPIO_PIN_PULLUP && flags & GPIO_PIN_PULLDOWN)
145 		return (EINVAL);
146 
147 	return (0);
148 }
149 
150 int
151 gpio_pin_get_by_bus_pinnum(device_t busdev, uint32_t pinnum, gpio_pin_t *ppin)
152 {
153 	gpio_pin_t pin;
154 	int err;
155 
156 	err = gpiobus_acquire_pin(busdev, pinnum);
157 	if (err != 0)
158 		return (EBUSY);
159 
160 	pin = malloc(sizeof(*pin), M_DEVBUF, M_WAITOK | M_ZERO);
161 
162 	pin->dev = device_get_parent(busdev);
163 	pin->pin = pinnum;
164 	pin->flags = 0;
165 
166 	*ppin = pin;
167 	return (0);
168 }
169 
170 int
171 gpio_pin_get_by_child_index(device_t childdev, uint32_t idx, gpio_pin_t *ppin)
172 {
173 	struct gpiobus_ivar *devi;
174 
175 	devi = GPIOBUS_IVAR(childdev);
176 	if (idx >= devi->npins)
177 		return (EINVAL);
178 
179 	return (gpio_pin_get_by_bus_pinnum(device_get_parent(childdev),
180 	    devi->pins[idx], ppin));
181 }
182 
183 int
184 gpio_pin_getcaps(gpio_pin_t pin, uint32_t *caps)
185 {
186 
187 	KASSERT(pin != NULL, ("GPIO pin is NULL."));
188 	KASSERT(pin->dev != NULL, ("GPIO pin device is NULL."));
189 	return (GPIO_PIN_GETCAPS(pin->dev, pin->pin, caps));
190 }
191 
192 int
193 gpio_pin_is_active(gpio_pin_t pin, bool *active)
194 {
195 	int rv;
196 	uint32_t tmp;
197 
198 	KASSERT(pin != NULL, ("GPIO pin is NULL."));
199 	KASSERT(pin->dev != NULL, ("GPIO pin device is NULL."));
200 	rv = GPIO_PIN_GET(pin->dev, pin->pin, &tmp);
201 	if (rv  != 0) {
202 		return (rv);
203 	}
204 
205 	if (pin->flags & GPIO_ACTIVE_LOW)
206 		*active = tmp == 0;
207 	else
208 		*active = tmp != 0;
209 	return (0);
210 }
211 
212 void
213 gpio_pin_release(gpio_pin_t gpio)
214 {
215 	device_t busdev;
216 
217 	if (gpio == NULL)
218 		return;
219 
220 	KASSERT(gpio->dev != NULL, ("GPIO pin device is NULL."));
221 
222 	busdev = GPIO_GET_BUS(gpio->dev);
223 	if (busdev != NULL)
224 		gpiobus_release_pin(busdev, gpio->pin);
225 
226 	free(gpio, M_DEVBUF);
227 }
228 
229 int
230 gpio_pin_set_active(gpio_pin_t pin, bool active)
231 {
232 	int rv;
233 	uint32_t tmp;
234 
235 	if (pin->flags & GPIO_ACTIVE_LOW)
236 		tmp = active ? 0 : 1;
237 	else
238 		tmp = active ? 1 : 0;
239 
240 	KASSERT(pin != NULL, ("GPIO pin is NULL."));
241 	KASSERT(pin->dev != NULL, ("GPIO pin device is NULL."));
242 	rv = GPIO_PIN_SET(pin->dev, pin->pin, tmp);
243 	return (rv);
244 }
245 
246 int
247 gpio_pin_setflags(gpio_pin_t pin, uint32_t flags)
248 {
249 	int rv;
250 
251 	KASSERT(pin != NULL, ("GPIO pin is NULL."));
252 	KASSERT(pin->dev != NULL, ("GPIO pin device is NULL."));
253 
254 	rv = GPIO_PIN_SETFLAGS(pin->dev, pin->pin, flags);
255 	return (rv);
256 }
257 
258 static void
259 gpiobus_print_pins(struct gpiobus_ivar *devi, char *buf, size_t buflen)
260 {
261 	char tmp[128];
262 	int i, range_start, range_stop, need_coma;
263 
264 	if (devi->npins == 0)
265 		return;
266 
267 	need_coma = 0;
268 	range_start = range_stop = devi->pins[0];
269 	for (i = 1; i < devi->npins; i++) {
270 		if (devi->pins[i] != (range_stop + 1)) {
271 			if (need_coma)
272 				strlcat(buf, ",", buflen);
273 			memset(tmp, 0, sizeof(tmp));
274 			if (range_start != range_stop)
275 				snprintf(tmp, sizeof(tmp) - 1, "%d-%d",
276 				    range_start, range_stop);
277 			else
278 				snprintf(tmp, sizeof(tmp) - 1, "%d",
279 				    range_start);
280 			strlcat(buf, tmp, buflen);
281 
282 			range_start = range_stop = devi->pins[i];
283 			need_coma = 1;
284 		}
285 		else
286 			range_stop++;
287 	}
288 
289 	if (need_coma)
290 		strlcat(buf, ",", buflen);
291 	memset(tmp, 0, sizeof(tmp));
292 	if (range_start != range_stop)
293 		snprintf(tmp, sizeof(tmp) - 1, "%d-%d",
294 		    range_start, range_stop);
295 	else
296 		snprintf(tmp, sizeof(tmp) - 1, "%d",
297 		    range_start);
298 	strlcat(buf, tmp, buflen);
299 }
300 
301 device_t
302 gpiobus_attach_bus(device_t dev)
303 {
304 	device_t busdev;
305 
306 	busdev = device_add_child(dev, "gpiobus", -1);
307 	if (busdev == NULL)
308 		return (NULL);
309 	if (device_add_child(dev, "gpioc", -1) == NULL) {
310 		device_delete_child(dev, busdev);
311 		return (NULL);
312 	}
313 #ifdef FDT
314 	ofw_gpiobus_register_provider(dev);
315 #endif
316 	bus_generic_attach(dev);
317 
318 	return (busdev);
319 }
320 
321 int
322 gpiobus_detach_bus(device_t dev)
323 {
324 	int err;
325 
326 #ifdef FDT
327 	ofw_gpiobus_unregister_provider(dev);
328 #endif
329 	err = bus_generic_detach(dev);
330 	if (err != 0)
331 		return (err);
332 
333 	return (device_delete_children(dev));
334 }
335 
336 int
337 gpiobus_init_softc(device_t dev)
338 {
339 	struct gpiobus_softc *sc;
340 
341 	sc = GPIOBUS_SOFTC(dev);
342 	sc->sc_busdev = dev;
343 	sc->sc_dev = device_get_parent(dev);
344 	sc->sc_intr_rman.rm_type = RMAN_ARRAY;
345 	sc->sc_intr_rman.rm_descr = "GPIO Interrupts";
346 	if (rman_init(&sc->sc_intr_rman) != 0 ||
347 	    rman_manage_region(&sc->sc_intr_rman, 0, ~0) != 0)
348 		panic("%s: failed to set up rman.", __func__);
349 
350 	if (GPIO_PIN_MAX(sc->sc_dev, &sc->sc_npins) != 0)
351 		return (ENXIO);
352 
353 	KASSERT(sc->sc_npins >= 0, ("GPIO device with no pins"));
354 
355 	/* Pins = GPIO_PIN_MAX() + 1 */
356 	sc->sc_npins++;
357 
358 	sc->sc_pins = malloc(sizeof(*sc->sc_pins) * sc->sc_npins, M_DEVBUF,
359 	    M_NOWAIT | M_ZERO);
360 	if (sc->sc_pins == NULL)
361 		return (ENOMEM);
362 
363 	/* Initialize the bus lock. */
364 	GPIOBUS_LOCK_INIT(sc);
365 
366 	return (0);
367 }
368 
369 int
370 gpiobus_alloc_ivars(struct gpiobus_ivar *devi)
371 {
372 
373 	/* Allocate pins and flags memory. */
374 	devi->pins = malloc(sizeof(uint32_t) * devi->npins, M_DEVBUF,
375 	    M_NOWAIT | M_ZERO);
376 	if (devi->pins == NULL)
377 		return (ENOMEM);
378 	return (0);
379 }
380 
381 void
382 gpiobus_free_ivars(struct gpiobus_ivar *devi)
383 {
384 
385 	if (devi->pins) {
386 		free(devi->pins, M_DEVBUF);
387 		devi->pins = NULL;
388 	}
389 	devi->npins = 0;
390 }
391 
392 int
393 gpiobus_acquire_pin(device_t bus, uint32_t pin)
394 {
395 	struct gpiobus_softc *sc;
396 
397 	sc = device_get_softc(bus);
398 	/* Consistency check. */
399 	if (pin >= sc->sc_npins) {
400 		device_printf(bus,
401 		    "invalid pin %d, max: %d\n", pin, sc->sc_npins - 1);
402 		return (-1);
403 	}
404 	/* Mark pin as mapped and give warning if it's already mapped. */
405 	if (sc->sc_pins[pin].mapped) {
406 		device_printf(bus, "warning: pin %d is already mapped\n", pin);
407 		return (-1);
408 	}
409 	sc->sc_pins[pin].mapped = 1;
410 
411 	return (0);
412 }
413 
414 /* Release mapped pin */
415 int
416 gpiobus_release_pin(device_t bus, uint32_t pin)
417 {
418 	struct gpiobus_softc *sc;
419 
420 	sc = device_get_softc(bus);
421 	/* Consistency check. */
422 	if (pin >= sc->sc_npins) {
423 		device_printf(bus,
424 		    "gpiobus_acquire_pin: invalid pin %d, max=%d\n",
425 		    pin, sc->sc_npins - 1);
426 		return (-1);
427 	}
428 
429 	if (!sc->sc_pins[pin].mapped) {
430 		device_printf(bus, "gpiobus_acquire_pin: pin %d is not mapped\n", pin);
431 		return (-1);
432 	}
433 	sc->sc_pins[pin].mapped = 0;
434 
435 	return (0);
436 }
437 
438 static int
439 gpiobus_acquire_child_pins(device_t dev, device_t child)
440 {
441 	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
442 	int i;
443 
444 	for (i = 0; i < devi->npins; i++) {
445 		/* Reserve the GPIO pin. */
446 		if (gpiobus_acquire_pin(dev, devi->pins[i]) != 0) {
447 			device_printf(child, "cannot acquire pin %d\n",
448 			    devi->pins[i]);
449 			while (--i >= 0) {
450 				(void)gpiobus_release_pin(dev,
451 				    devi->pins[i]);
452 			}
453 			gpiobus_free_ivars(devi);
454 			return (EBUSY);
455 		}
456 	}
457 	for (i = 0; i < devi->npins; i++) {
458 		/* Use the child name as pin name. */
459 		GPIOBUS_PIN_SETNAME(dev, devi->pins[i],
460 		    device_get_nameunit(child));
461 
462 	}
463 	return (0);
464 }
465 
466 static int
467 gpiobus_parse_pins(struct gpiobus_softc *sc, device_t child, int mask)
468 {
469 	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
470 	int i, npins;
471 
472 	npins = 0;
473 	for (i = 0; i < 32; i++) {
474 		if (mask & (1 << i))
475 			npins++;
476 	}
477 	if (npins == 0) {
478 		device_printf(child, "empty pin mask\n");
479 		return (EINVAL);
480 	}
481 	devi->npins = npins;
482 	if (gpiobus_alloc_ivars(devi) != 0) {
483 		device_printf(child, "cannot allocate device ivars\n");
484 		return (EINVAL);
485 	}
486 	npins = 0;
487 	for (i = 0; i < 32; i++) {
488 		if ((mask & (1 << i)) == 0)
489 			continue;
490 		devi->pins[npins++] = i;
491 	}
492 
493 	return (0);
494 }
495 
496 static int
497 gpiobus_parse_pin_list(struct gpiobus_softc *sc, device_t child,
498     const char *pins)
499 {
500 	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
501 	const char *p;
502 	char *endp;
503 	unsigned long pin;
504 	int i, npins;
505 
506 	npins = 0;
507 	p = pins;
508 	for (;;) {
509 		pin = strtoul(p, &endp, 0);
510 		if (endp == p)
511 			break;
512 		npins++;
513 		if (*endp == '\0')
514 			break;
515 		p = endp + 1;
516 	}
517 
518 	if (*endp != '\0') {
519 		device_printf(child, "garbage in the pin list: %s\n", endp);
520 		return (EINVAL);
521 	}
522 	if (npins == 0) {
523 		device_printf(child, "empty pin list\n");
524 		return (EINVAL);
525 	}
526 
527 	devi->npins = npins;
528 	if (gpiobus_alloc_ivars(devi) != 0) {
529 		device_printf(child, "cannot allocate device ivars\n");
530 		return (EINVAL);
531 	}
532 
533 	i = 0;
534 	p = pins;
535 	for (;;) {
536 		pin = strtoul(p, &endp, 0);
537 
538 		devi->pins[i] = pin;
539 
540 		if (*endp == '\0')
541 			break;
542 		i++;
543 		p = endp + 1;
544 	}
545 
546 	return (0);
547 }
548 
549 static int
550 gpiobus_probe(device_t dev)
551 {
552 	device_set_desc(dev, "GPIO bus");
553 
554 	return (BUS_PROBE_GENERIC);
555 }
556 
557 static int
558 gpiobus_attach(device_t dev)
559 {
560 	int err;
561 
562 	err = gpiobus_init_softc(dev);
563 	if (err != 0)
564 		return (err);
565 
566 	/*
567 	 * Get parent's pins and mark them as unmapped
568 	 */
569 	bus_generic_probe(dev);
570 	bus_enumerate_hinted_children(dev);
571 
572 	return (bus_generic_attach(dev));
573 }
574 
575 /*
576  * Since this is not a self-enumerating bus, and since we always add
577  * children in attach, we have to always delete children here.
578  */
579 static int
580 gpiobus_detach(device_t dev)
581 {
582 	struct gpiobus_softc *sc;
583 	struct gpiobus_ivar *devi;
584 	device_t *devlist;
585 	int i, err, ndevs;
586 
587 	sc = GPIOBUS_SOFTC(dev);
588 	KASSERT(mtx_initialized(&sc->sc_mtx),
589 	    ("gpiobus mutex not initialized"));
590 	GPIOBUS_LOCK_DESTROY(sc);
591 
592 	if ((err = bus_generic_detach(dev)) != 0)
593 		return (err);
594 
595 	if ((err = device_get_children(dev, &devlist, &ndevs)) != 0)
596 		return (err);
597 	for (i = 0; i < ndevs; i++) {
598 		devi = GPIOBUS_IVAR(devlist[i]);
599 		gpiobus_free_ivars(devi);
600 		resource_list_free(&devi->rl);
601 		free(devi, M_DEVBUF);
602 		device_delete_child(dev, devlist[i]);
603 	}
604 	free(devlist, M_TEMP);
605 	rman_fini(&sc->sc_intr_rman);
606 	if (sc->sc_pins) {
607 		for (i = 0; i < sc->sc_npins; i++) {
608 			if (sc->sc_pins[i].name != NULL)
609 				free(sc->sc_pins[i].name, M_DEVBUF);
610 			sc->sc_pins[i].name = NULL;
611 		}
612 		free(sc->sc_pins, M_DEVBUF);
613 		sc->sc_pins = NULL;
614 	}
615 
616 	return (0);
617 }
618 
619 static int
620 gpiobus_suspend(device_t dev)
621 {
622 
623 	return (bus_generic_suspend(dev));
624 }
625 
626 static int
627 gpiobus_resume(device_t dev)
628 {
629 
630 	return (bus_generic_resume(dev));
631 }
632 
633 static void
634 gpiobus_probe_nomatch(device_t dev, device_t child)
635 {
636 	char pins[128];
637 	struct gpiobus_ivar *devi;
638 
639 	devi = GPIOBUS_IVAR(child);
640 	memset(pins, 0, sizeof(pins));
641 	gpiobus_print_pins(devi, pins, sizeof(pins));
642 	if (devi->npins > 1)
643 		device_printf(dev, "<unknown device> at pins %s", pins);
644 	else
645 		device_printf(dev, "<unknown device> at pin %s", pins);
646 	resource_list_print_type(&devi->rl, "irq", SYS_RES_IRQ, "%jd");
647 	printf("\n");
648 }
649 
650 static int
651 gpiobus_print_child(device_t dev, device_t child)
652 {
653 	char pins[128];
654 	int retval = 0;
655 	struct gpiobus_ivar *devi;
656 
657 	devi = GPIOBUS_IVAR(child);
658 	memset(pins, 0, sizeof(pins));
659 	retval += bus_print_child_header(dev, child);
660 	if (devi->npins > 0) {
661 		if (devi->npins > 1)
662 			retval += printf(" at pins ");
663 		else
664 			retval += printf(" at pin ");
665 		gpiobus_print_pins(devi, pins, sizeof(pins));
666 		retval += printf("%s", pins);
667 	}
668 	resource_list_print_type(&devi->rl, "irq", SYS_RES_IRQ, "%jd");
669 	retval += bus_print_child_footer(dev, child);
670 
671 	return (retval);
672 }
673 
674 static int
675 gpiobus_child_location_str(device_t bus, device_t child, char *buf,
676     size_t buflen)
677 {
678 	struct gpiobus_ivar *devi;
679 
680 	devi = GPIOBUS_IVAR(child);
681 	if (devi->npins > 1)
682 		strlcpy(buf, "pins=", buflen);
683 	else
684 		strlcpy(buf, "pin=", buflen);
685 	gpiobus_print_pins(devi, buf, buflen);
686 
687 	return (0);
688 }
689 
690 static int
691 gpiobus_child_pnpinfo_str(device_t bus, device_t child, char *buf,
692     size_t buflen)
693 {
694 
695 	*buf = '\0';
696 	return (0);
697 }
698 
699 static device_t
700 gpiobus_add_child(device_t dev, u_int order, const char *name, int unit)
701 {
702 	device_t child;
703 	struct gpiobus_ivar *devi;
704 
705 	child = device_add_child_ordered(dev, order, name, unit);
706 	if (child == NULL)
707 		return (child);
708 	devi = malloc(sizeof(struct gpiobus_ivar), M_DEVBUF, M_NOWAIT | M_ZERO);
709 	if (devi == NULL) {
710 		device_delete_child(dev, child);
711 		return (NULL);
712 	}
713 	resource_list_init(&devi->rl);
714 	device_set_ivars(child, devi);
715 
716 	return (child);
717 }
718 
719 static int
720 gpiobus_rescan(device_t dev)
721 {
722 
723 	/*
724 	 * Re-scan is supposed to remove and add children, but if someone has
725 	 * deleted the hints for a child we attached earlier, we have no easy
726 	 * way to handle that.  So this just attaches new children for whom new
727 	 * hints or drivers have arrived since we last tried.
728 	 */
729 	bus_enumerate_hinted_children(dev);
730 	bus_generic_attach(dev);
731 	return (0);
732 }
733 
734 static void
735 gpiobus_hinted_child(device_t bus, const char *dname, int dunit)
736 {
737 	struct gpiobus_softc *sc = GPIOBUS_SOFTC(bus);
738 	struct gpiobus_ivar *devi;
739 	device_t child;
740 	const char *pins;
741 	int irq, pinmask;
742 
743 	if (device_find_child(bus, dname, dunit) != NULL) {
744 		return;
745 	}
746 
747 	child = BUS_ADD_CHILD(bus, 0, dname, dunit);
748 	devi = GPIOBUS_IVAR(child);
749 	if (resource_int_value(dname, dunit, "pins", &pinmask) == 0) {
750 		if (gpiobus_parse_pins(sc, child, pinmask)) {
751 			resource_list_free(&devi->rl);
752 			free(devi, M_DEVBUF);
753 			device_delete_child(bus, child);
754 			return;
755 		}
756 	}
757 	else if (resource_string_value(dname, dunit, "pin_list", &pins) == 0) {
758 		if (gpiobus_parse_pin_list(sc, child, pins)) {
759 			resource_list_free(&devi->rl);
760 			free(devi, M_DEVBUF);
761 			device_delete_child(bus, child);
762 			return;
763 		}
764 	}
765 	if (resource_int_value(dname, dunit, "irq", &irq) == 0) {
766 		if (bus_set_resource(child, SYS_RES_IRQ, 0, irq, 1) != 0)
767 			device_printf(bus,
768 			    "warning: bus_set_resource() failed\n");
769 	}
770 }
771 
772 static int
773 gpiobus_set_resource(device_t dev, device_t child, int type, int rid,
774     rman_res_t start, rman_res_t count)
775 {
776 	struct gpiobus_ivar *devi;
777 	struct resource_list_entry *rle;
778 
779 	dprintf("%s: entry (%p, %p, %d, %d, %p, %ld)\n",
780 	    __func__, dev, child, type, rid, (void *)(intptr_t)start, count);
781 	devi = GPIOBUS_IVAR(child);
782 	rle = resource_list_add(&devi->rl, type, rid, start,
783 	    start + count - 1, count);
784 	if (rle == NULL)
785 		return (ENXIO);
786 
787 	return (0);
788 }
789 
790 static int
791 gpiobus_read_ivar(device_t dev, device_t child, int which, uintptr_t *result)
792 {
793 	struct gpiobus_ivar *devi;
794 
795 	devi = GPIOBUS_IVAR(child);
796         switch (which) {
797 	case GPIOBUS_IVAR_NPINS:
798 		*result = devi->npins;
799 		break;
800 	case GPIOBUS_IVAR_PINS:
801 		/* Children do not ever need to directly examine this. */
802 		return (ENOTSUP);
803         default:
804                 return (ENOENT);
805         }
806 
807 	return (0);
808 }
809 
810 static int
811 gpiobus_write_ivar(device_t dev, device_t child, int which, uintptr_t value)
812 {
813 	struct gpiobus_ivar *devi;
814 	const uint32_t *ptr;
815 	int i;
816 
817 	devi = GPIOBUS_IVAR(child);
818         switch (which) {
819 	case GPIOBUS_IVAR_NPINS:
820 		/* GPIO ivars are set once. */
821 		if (devi->npins != 0) {
822 			return (EBUSY);
823 		}
824 		devi->npins = value;
825 		if (gpiobus_alloc_ivars(devi) != 0) {
826 			device_printf(child, "cannot allocate device ivars\n");
827 			devi->npins = 0;
828 			return (ENOMEM);
829 		}
830 		break;
831 	case GPIOBUS_IVAR_PINS:
832 		ptr = (const uint32_t *)value;
833 		for (i = 0; i < devi->npins; i++)
834 			devi->pins[i] = ptr[i];
835 		if (gpiobus_acquire_child_pins(dev, child) != 0)
836 			return (EBUSY);
837 		break;
838         default:
839                 return (ENOENT);
840         }
841 
842         return (0);
843 }
844 
845 static struct resource *
846 gpiobus_alloc_resource(device_t bus, device_t child, int type, int *rid,
847     rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
848 {
849 	struct gpiobus_softc *sc;
850 	struct resource *rv;
851 	struct resource_list *rl;
852 	struct resource_list_entry *rle;
853 	int isdefault;
854 
855 	if (type != SYS_RES_IRQ)
856 		return (NULL);
857 	isdefault = (RMAN_IS_DEFAULT_RANGE(start, end) && count == 1);
858 	rle = NULL;
859 	if (isdefault) {
860 		rl = BUS_GET_RESOURCE_LIST(bus, child);
861 		if (rl == NULL)
862 			return (NULL);
863 		rle = resource_list_find(rl, type, *rid);
864 		if (rle == NULL)
865 			return (NULL);
866 		if (rle->res != NULL)
867 			panic("%s: resource entry is busy", __func__);
868 		start = rle->start;
869 		count = rle->count;
870 		end = rle->end;
871 	}
872 	sc = device_get_softc(bus);
873 	rv = rman_reserve_resource(&sc->sc_intr_rman, start, end, count, flags,
874 	    child);
875 	if (rv == NULL)
876 		return (NULL);
877 	rman_set_rid(rv, *rid);
878 	if ((flags & RF_ACTIVE) != 0 &&
879 	    bus_activate_resource(child, type, *rid, rv) != 0) {
880 		rman_release_resource(rv);
881 		return (NULL);
882 	}
883 
884 	return (rv);
885 }
886 
887 static int
888 gpiobus_release_resource(device_t bus __unused, device_t child, int type,
889     int rid, struct resource *r)
890 {
891 	int error;
892 
893 	if (rman_get_flags(r) & RF_ACTIVE) {
894 		error = bus_deactivate_resource(child, type, rid, r);
895 		if (error)
896 			return (error);
897 	}
898 
899 	return (rman_release_resource(r));
900 }
901 
902 static struct resource_list *
903 gpiobus_get_resource_list(device_t bus __unused, device_t child)
904 {
905 	struct gpiobus_ivar *ivar;
906 
907 	ivar = GPIOBUS_IVAR(child);
908 
909 	return (&ivar->rl);
910 }
911 
912 static int
913 gpiobus_acquire_bus(device_t busdev, device_t child, int how)
914 {
915 	struct gpiobus_softc *sc;
916 
917 	sc = device_get_softc(busdev);
918 	GPIOBUS_ASSERT_UNLOCKED(sc);
919 	GPIOBUS_LOCK(sc);
920 	if (sc->sc_owner != NULL) {
921 		if (sc->sc_owner == child)
922 			panic("%s: %s still owns the bus.",
923 			    device_get_nameunit(busdev),
924 			    device_get_nameunit(child));
925 		if (how == GPIOBUS_DONTWAIT) {
926 			GPIOBUS_UNLOCK(sc);
927 			return (EWOULDBLOCK);
928 		}
929 		while (sc->sc_owner != NULL)
930 			mtx_sleep(sc, &sc->sc_mtx, 0, "gpiobuswait", 0);
931 	}
932 	sc->sc_owner = child;
933 	GPIOBUS_UNLOCK(sc);
934 
935 	return (0);
936 }
937 
938 static void
939 gpiobus_release_bus(device_t busdev, device_t child)
940 {
941 	struct gpiobus_softc *sc;
942 
943 	sc = device_get_softc(busdev);
944 	GPIOBUS_ASSERT_UNLOCKED(sc);
945 	GPIOBUS_LOCK(sc);
946 	if (sc->sc_owner == NULL)
947 		panic("%s: %s releasing unowned bus.",
948 		    device_get_nameunit(busdev),
949 		    device_get_nameunit(child));
950 	if (sc->sc_owner != child)
951 		panic("%s: %s trying to release bus owned by %s",
952 		    device_get_nameunit(busdev),
953 		    device_get_nameunit(child),
954 		    device_get_nameunit(sc->sc_owner));
955 	sc->sc_owner = NULL;
956 	wakeup(sc);
957 	GPIOBUS_UNLOCK(sc);
958 }
959 
960 static int
961 gpiobus_pin_setflags(device_t dev, device_t child, uint32_t pin,
962     uint32_t flags)
963 {
964 	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
965 	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
966 	uint32_t caps;
967 
968 	if (pin >= devi->npins)
969 		return (EINVAL);
970 	if (GPIO_PIN_GETCAPS(sc->sc_dev, devi->pins[pin], &caps) != 0)
971 		return (EINVAL);
972 	if (gpio_check_flags(caps, flags) != 0)
973 		return (EINVAL);
974 
975 	return (GPIO_PIN_SETFLAGS(sc->sc_dev, devi->pins[pin], flags));
976 }
977 
978 static int
979 gpiobus_pin_getflags(device_t dev, device_t child, uint32_t pin,
980     uint32_t *flags)
981 {
982 	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
983 	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
984 
985 	if (pin >= devi->npins)
986 		return (EINVAL);
987 
988 	return GPIO_PIN_GETFLAGS(sc->sc_dev, devi->pins[pin], flags);
989 }
990 
991 static int
992 gpiobus_pin_getcaps(device_t dev, device_t child, uint32_t pin,
993     uint32_t *caps)
994 {
995 	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
996 	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
997 
998 	if (pin >= devi->npins)
999 		return (EINVAL);
1000 
1001 	return GPIO_PIN_GETCAPS(sc->sc_dev, devi->pins[pin], caps);
1002 }
1003 
1004 static int
1005 gpiobus_pin_set(device_t dev, device_t child, uint32_t pin,
1006     unsigned int value)
1007 {
1008 	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
1009 	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
1010 
1011 	if (pin >= devi->npins)
1012 		return (EINVAL);
1013 
1014 	return GPIO_PIN_SET(sc->sc_dev, devi->pins[pin], value);
1015 }
1016 
1017 static int
1018 gpiobus_pin_get(device_t dev, device_t child, uint32_t pin,
1019     unsigned int *value)
1020 {
1021 	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
1022 	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
1023 
1024 	if (pin >= devi->npins)
1025 		return (EINVAL);
1026 
1027 	return GPIO_PIN_GET(sc->sc_dev, devi->pins[pin], value);
1028 }
1029 
1030 static int
1031 gpiobus_pin_toggle(device_t dev, device_t child, uint32_t pin)
1032 {
1033 	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
1034 	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
1035 
1036 	if (pin >= devi->npins)
1037 		return (EINVAL);
1038 
1039 	return GPIO_PIN_TOGGLE(sc->sc_dev, devi->pins[pin]);
1040 }
1041 
1042 static int
1043 gpiobus_pin_getname(device_t dev, uint32_t pin, char *name)
1044 {
1045 	struct gpiobus_softc *sc;
1046 
1047 	sc = GPIOBUS_SOFTC(dev);
1048 	if (pin > sc->sc_npins)
1049 		return (EINVAL);
1050 	/* Did we have a name for this pin ? */
1051 	if (sc->sc_pins[pin].name != NULL) {
1052 		memcpy(name, sc->sc_pins[pin].name, GPIOMAXNAME);
1053 		return (0);
1054 	}
1055 
1056 	/* Return the default pin name. */
1057 	return (GPIO_PIN_GETNAME(device_get_parent(dev), pin, name));
1058 }
1059 
1060 static int
1061 gpiobus_pin_setname(device_t dev, uint32_t pin, const char *name)
1062 {
1063 	struct gpiobus_softc *sc;
1064 
1065 	sc = GPIOBUS_SOFTC(dev);
1066 	if (pin > sc->sc_npins)
1067 		return (EINVAL);
1068 	if (name == NULL)
1069 		return (EINVAL);
1070 	/* Save the pin name. */
1071 	if (sc->sc_pins[pin].name == NULL)
1072 		sc->sc_pins[pin].name = malloc(GPIOMAXNAME, M_DEVBUF,
1073 		    M_WAITOK | M_ZERO);
1074 	strlcpy(sc->sc_pins[pin].name, name, GPIOMAXNAME);
1075 
1076 	return (0);
1077 }
1078 
1079 static device_method_t gpiobus_methods[] = {
1080 	/* Device interface */
1081 	DEVMETHOD(device_probe,		gpiobus_probe),
1082 	DEVMETHOD(device_attach,	gpiobus_attach),
1083 	DEVMETHOD(device_detach,	gpiobus_detach),
1084 	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
1085 	DEVMETHOD(device_suspend,	gpiobus_suspend),
1086 	DEVMETHOD(device_resume,	gpiobus_resume),
1087 
1088 	/* Bus interface */
1089 	DEVMETHOD(bus_setup_intr,	bus_generic_setup_intr),
1090 	DEVMETHOD(bus_config_intr,	bus_generic_config_intr),
1091 	DEVMETHOD(bus_teardown_intr,	bus_generic_teardown_intr),
1092 	DEVMETHOD(bus_set_resource,	gpiobus_set_resource),
1093 	DEVMETHOD(bus_alloc_resource,	gpiobus_alloc_resource),
1094 	DEVMETHOD(bus_release_resource,	gpiobus_release_resource),
1095 	DEVMETHOD(bus_activate_resource,	bus_generic_activate_resource),
1096 	DEVMETHOD(bus_deactivate_resource,	bus_generic_deactivate_resource),
1097 	DEVMETHOD(bus_get_resource_list,	gpiobus_get_resource_list),
1098 	DEVMETHOD(bus_add_child,	gpiobus_add_child),
1099 	DEVMETHOD(bus_rescan,		gpiobus_rescan),
1100 	DEVMETHOD(bus_probe_nomatch,	gpiobus_probe_nomatch),
1101 	DEVMETHOD(bus_print_child,	gpiobus_print_child),
1102 	DEVMETHOD(bus_child_pnpinfo_str, gpiobus_child_pnpinfo_str),
1103 	DEVMETHOD(bus_child_location_str, gpiobus_child_location_str),
1104 	DEVMETHOD(bus_hinted_child,	gpiobus_hinted_child),
1105 	DEVMETHOD(bus_read_ivar,        gpiobus_read_ivar),
1106 	DEVMETHOD(bus_write_ivar,       gpiobus_write_ivar),
1107 
1108 	/* GPIO protocol */
1109 	DEVMETHOD(gpiobus_acquire_bus,	gpiobus_acquire_bus),
1110 	DEVMETHOD(gpiobus_release_bus,	gpiobus_release_bus),
1111 	DEVMETHOD(gpiobus_pin_getflags,	gpiobus_pin_getflags),
1112 	DEVMETHOD(gpiobus_pin_getcaps,	gpiobus_pin_getcaps),
1113 	DEVMETHOD(gpiobus_pin_setflags,	gpiobus_pin_setflags),
1114 	DEVMETHOD(gpiobus_pin_get,	gpiobus_pin_get),
1115 	DEVMETHOD(gpiobus_pin_set,	gpiobus_pin_set),
1116 	DEVMETHOD(gpiobus_pin_toggle,	gpiobus_pin_toggle),
1117 	DEVMETHOD(gpiobus_pin_getname,	gpiobus_pin_getname),
1118 	DEVMETHOD(gpiobus_pin_setname,	gpiobus_pin_setname),
1119 
1120 	DEVMETHOD_END
1121 };
1122 
1123 driver_t gpiobus_driver = {
1124 	"gpiobus",
1125 	gpiobus_methods,
1126 	sizeof(struct gpiobus_softc)
1127 };
1128 
1129 devclass_t	gpiobus_devclass;
1130 
1131 EARLY_DRIVER_MODULE(gpiobus, gpio, gpiobus_driver, gpiobus_devclass, 0, 0,
1132     BUS_PASS_BUS + BUS_PASS_ORDER_MIDDLE);
1133 MODULE_VERSION(gpiobus, 1);
1134