xref: /freebsd/sys/dev/gpio/gpiobus.c (revision d5f55356a2fbf8222fb236fe509821e12f1ea456)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
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/param.h>
30 #include <sys/systm.h>
31 #include <sys/bus.h>
32 #include <sys/gpio.h>
33 #ifdef INTRNG
34 #include <sys/intr.h>
35 #endif
36 #include <sys/kernel.h>
37 #include <sys/malloc.h>
38 #include <sys/module.h>
39 #include <sys/sbuf.h>
40 
41 #include <dev/gpio/gpiobusvar.h>
42 #include <dev/gpio/gpiobus_internal.h>
43 
44 #include "gpiobus_if.h"
45 
46 #undef GPIOBUS_DEBUG
47 #ifdef GPIOBUS_DEBUG
48 #define	dprintf printf
49 #else
50 #define	dprintf(x, arg...)
51 #endif
52 
53 static void gpiobus_print_pins(struct gpiobus_ivar *, struct sbuf *);
54 static int gpiobus_parse_pins(struct gpiobus_softc *, device_t, int);
55 static int gpiobus_probe(device_t);
56 static int gpiobus_suspend(device_t);
57 static int gpiobus_resume(device_t);
58 static void gpiobus_probe_nomatch(device_t, device_t);
59 static int gpiobus_print_child(device_t, device_t);
60 static int gpiobus_child_location(device_t, device_t, struct sbuf *);
61 static device_t gpiobus_add_child(device_t, u_int, const char *, int);
62 static void gpiobus_hinted_child(device_t, const char *, int);
63 
64 /*
65  * GPIOBUS interface
66  */
67 static int gpiobus_acquire_bus(device_t, device_t, int);
68 static void gpiobus_release_bus(device_t, device_t);
69 static int gpiobus_pin_setflags(device_t, device_t, uint32_t, uint32_t);
70 static int gpiobus_pin_getflags(device_t, device_t, uint32_t, uint32_t*);
71 static int gpiobus_pin_getcaps(device_t, device_t, uint32_t, uint32_t*);
72 static int gpiobus_pin_set(device_t, device_t, uint32_t, unsigned int);
73 static int gpiobus_pin_get(device_t, device_t, uint32_t, unsigned int*);
74 static int gpiobus_pin_toggle(device_t, device_t, uint32_t);
75 
76 /*
77  * gpiobus_pin flags
78  *  The flags in struct gpiobus_pin are not related to the flags used by the
79  *  low-level controller driver in struct gpio_pin.  Currently, only pins
80  *  acquired via FDT data have gpiobus_pin.flags set, sourced from the flags in
81  *  the FDT properties.  In theory, these flags are defined per-platform.  In
82  *  practice they are always the flags from the dt-bindings/gpio/gpio.h file.
83  *  The only one of those flags we currently support is for handling active-low
84  *  pins, so we just define that flag here instead of including a GPL'd header.
85  */
86 #define	GPIO_ACTIVE_LOW 1
87 
88 /*
89  * XXX -> Move me to better place - gpio_subr.c?
90  * Also, this function must be changed when interrupt configuration
91  * data will be moved into struct resource.
92  */
93 #ifdef INTRNG
94 
95 struct resource *
96 gpio_alloc_intr_resource(device_t consumer_dev, int *rid, u_int alloc_flags,
97     gpio_pin_t pin, uint32_t intr_mode)
98 {
99 	u_int irq;
100 	struct intr_map_data_gpio *gpio_data;
101 	struct resource *res;
102 
103 	gpio_data = (struct intr_map_data_gpio *)intr_alloc_map_data(
104 	    INTR_MAP_DATA_GPIO, sizeof(*gpio_data), M_WAITOK | M_ZERO);
105 	gpio_data->gpio_pin_num = pin->pin;
106 	gpio_data->gpio_pin_flags = pin->flags;
107 	gpio_data->gpio_intr_mode = intr_mode;
108 
109 	irq = intr_map_irq(pin->dev, 0, (struct intr_map_data *)gpio_data);
110 	res = bus_alloc_resource(consumer_dev, SYS_RES_IRQ, rid, irq, irq, 1,
111 	    alloc_flags);
112 	if (res == NULL) {
113 		intr_unmap_irq(irq);
114 		return (NULL);
115 	}
116 	return (res);
117 }
118 #else
119 struct resource *
120 gpio_alloc_intr_resource(device_t consumer_dev, int *rid, u_int alloc_flags,
121     gpio_pin_t pin, uint32_t intr_mode)
122 {
123 
124 	return (NULL);
125 }
126 #endif
127 
128 int
129 gpio_check_flags(uint32_t caps, uint32_t flags)
130 {
131 
132 	/* Filter unwanted flags. */
133 	flags &= caps;
134 
135 	/* Cannot mix input/output together. */
136 	if (flags & GPIO_PIN_INPUT && flags & GPIO_PIN_OUTPUT)
137 		return (EINVAL);
138 	/* Cannot mix pull-up/pull-down together. */
139 	if (flags & GPIO_PIN_PULLUP && flags & GPIO_PIN_PULLDOWN)
140 		return (EINVAL);
141 	/* Cannot mix output and interrupt flags together */
142 	if (flags & GPIO_PIN_OUTPUT && flags & GPIO_INTR_MASK)
143 		return (EINVAL);
144 	/* Only one interrupt flag can be defined at once */
145 	if ((flags & GPIO_INTR_MASK) & ((flags & GPIO_INTR_MASK) - 1))
146 		return (EINVAL);
147 	/* The interrupt attached flag cannot be set */
148 	if (flags & GPIO_INTR_ATTACHED)
149 		return (EINVAL);
150 
151 	return (0);
152 }
153 
154 int
155 gpio_pin_get_by_bus_pinnum(device_t busdev, uint32_t pinnum, gpio_pin_t *ppin)
156 {
157 	gpio_pin_t pin;
158 	int err;
159 
160 	err = gpiobus_acquire_pin(busdev, pinnum);
161 	if (err != 0)
162 		return (EBUSY);
163 
164 	pin = malloc(sizeof(*pin), M_DEVBUF, M_WAITOK | M_ZERO);
165 
166 	pin->dev = device_get_parent(busdev);
167 	pin->pin = pinnum;
168 	pin->flags = 0;
169 
170 	*ppin = pin;
171 	return (0);
172 }
173 
174 int
175 gpio_pin_get_by_child_index(device_t childdev, uint32_t idx, gpio_pin_t *ppin)
176 {
177 	struct gpiobus_ivar *devi;
178 
179 	devi = GPIOBUS_IVAR(childdev);
180 	if (idx >= devi->npins)
181 		return (EINVAL);
182 
183 	return (gpio_pin_get_by_bus_pinnum(device_get_parent(childdev),
184 	    devi->pins[idx], ppin));
185 }
186 
187 int
188 gpio_pin_getcaps(gpio_pin_t pin, uint32_t *caps)
189 {
190 
191 	KASSERT(pin != NULL, ("GPIO pin is NULL."));
192 	KASSERT(pin->dev != NULL, ("GPIO pin device is NULL."));
193 	return (GPIO_PIN_GETCAPS(pin->dev, pin->pin, caps));
194 }
195 
196 int
197 gpio_pin_is_active(gpio_pin_t pin, bool *active)
198 {
199 	int rv;
200 	uint32_t tmp;
201 
202 	KASSERT(pin != NULL, ("GPIO pin is NULL."));
203 	KASSERT(pin->dev != NULL, ("GPIO pin device is NULL."));
204 	rv = GPIO_PIN_GET(pin->dev, pin->pin, &tmp);
205 	if (rv  != 0) {
206 		return (rv);
207 	}
208 
209 	if (pin->flags & GPIO_ACTIVE_LOW)
210 		*active = tmp == 0;
211 	else
212 		*active = tmp != 0;
213 	return (0);
214 }
215 
216 /*
217  * Note that this function should only
218  * be used in cases where a pre-existing
219  * gpiobus_pin structure exists. In most
220  * cases, the gpio_pin_get_by_* functions
221  * suffice.
222  */
223 int
224 gpio_pin_acquire(gpio_pin_t gpio)
225 {
226 	device_t busdev;
227 
228 	KASSERT(gpio != NULL, ("GPIO pin is NULL."));
229 	KASSERT(gpio->dev != NULL, ("GPIO pin device is NULL."));
230 
231 	busdev = GPIO_GET_BUS(gpio->dev);
232 	if (busdev == NULL)
233 		return (ENXIO);
234 
235 	return (gpiobus_acquire_pin(busdev, gpio->pin));
236 }
237 
238 void
239 gpio_pin_release(gpio_pin_t gpio)
240 {
241 	device_t busdev;
242 
243 	KASSERT(gpio != NULL, ("GPIO pin is NULL."));
244 	KASSERT(gpio->dev != NULL, ("GPIO pin device is NULL."));
245 
246 	busdev = GPIO_GET_BUS(gpio->dev);
247 	KASSERT(busdev != NULL, ("gpiobus dev is NULL."));
248 
249 	gpiobus_release_pin(busdev, gpio->pin);
250 	free(gpio, M_DEVBUF);
251 }
252 
253 int
254 gpio_pin_set_active(gpio_pin_t pin, bool active)
255 {
256 	int rv;
257 	uint32_t tmp;
258 
259 	if (pin->flags & GPIO_ACTIVE_LOW)
260 		tmp = active ? 0 : 1;
261 	else
262 		tmp = active ? 1 : 0;
263 
264 	KASSERT(pin != NULL, ("GPIO pin is NULL."));
265 	KASSERT(pin->dev != NULL, ("GPIO pin device is NULL."));
266 	rv = GPIO_PIN_SET(pin->dev, pin->pin, tmp);
267 	return (rv);
268 }
269 
270 int
271 gpio_pin_setflags(gpio_pin_t pin, uint32_t flags)
272 {
273 	int rv;
274 
275 	KASSERT(pin != NULL, ("GPIO pin is NULL."));
276 	KASSERT(pin->dev != NULL, ("GPIO pin device is NULL."));
277 
278 	rv = GPIO_PIN_SETFLAGS(pin->dev, pin->pin, flags);
279 	return (rv);
280 }
281 
282 static void
283 gpiobus_print_pins(struct gpiobus_ivar *devi, struct sbuf *sb)
284 {
285 	int i, range_start, range_stop, need_coma;
286 
287 	if (devi->npins == 0)
288 		return;
289 
290 	need_coma = 0;
291 	range_start = range_stop = devi->pins[0];
292 	for (i = 1; i < devi->npins; i++) {
293 		if (devi->pins[i] != (range_stop + 1)) {
294 			if (need_coma)
295 				sbuf_cat(sb, ",");
296 			if (range_start != range_stop)
297 				sbuf_printf(sb, "%d-%d", range_start, range_stop);
298 			else
299 				sbuf_printf(sb, "%d", range_start);
300 			range_start = range_stop = devi->pins[i];
301 			need_coma = 1;
302 		}
303 		else
304 			range_stop++;
305 	}
306 
307 	if (need_coma)
308 		sbuf_cat(sb, ",");
309 	if (range_start != range_stop)
310 		sbuf_printf(sb, "%d-%d", range_start, range_stop);
311 	else
312 		sbuf_printf(sb, "%d", range_start);
313 }
314 
315 device_t
316 gpiobus_add_bus(device_t dev)
317 {
318 	device_t busdev;
319 
320 	busdev = device_add_child(dev, "gpiobus", DEVICE_UNIT_ANY);
321 	if (busdev == NULL)
322 		return (NULL);
323 	if (device_add_child(dev, "gpioc", DEVICE_UNIT_ANY) == NULL) {
324 		device_delete_child(dev, busdev);
325 		return (NULL);
326 	}
327 #ifdef FDT
328 	ofw_gpiobus_register_provider(dev);
329 #endif
330 	return (busdev);
331 }
332 
333 int
334 gpiobus_detach_bus(device_t dev)
335 {
336 #ifdef FDT
337 	ofw_gpiobus_unregister_provider(dev);
338 #endif
339 	return (bus_generic_detach(dev));
340 }
341 
342 int
343 gpiobus_init_softc(device_t dev)
344 {
345 	struct gpiobus_softc *sc;
346 
347 	sc = GPIOBUS_SOFTC(dev);
348 	sc->sc_busdev = dev;
349 	sc->sc_dev = device_get_parent(dev);
350 	sc->sc_intr_rman.rm_type = RMAN_ARRAY;
351 	sc->sc_intr_rman.rm_descr = "GPIO Interrupts";
352 	if (rman_init(&sc->sc_intr_rman) != 0 ||
353 	    rman_manage_region(&sc->sc_intr_rman, 0, ~0) != 0)
354 		panic("%s: failed to set up rman.", __func__);
355 
356 	if (GPIO_PIN_MAX(sc->sc_dev, &sc->sc_npins) != 0)
357 		return (ENXIO);
358 
359 	KASSERT(sc->sc_npins >= 0, ("GPIO device with no pins"));
360 
361 	/* Pins = GPIO_PIN_MAX() + 1 */
362 	sc->sc_npins++;
363 
364 	sc->sc_pins = malloc(sizeof(*sc->sc_pins) * sc->sc_npins, M_DEVBUF,
365 	    M_NOWAIT | M_ZERO);
366 	if (sc->sc_pins == NULL)
367 		return (ENOMEM);
368 
369 	/* Initialize the bus lock. */
370 	GPIOBUS_LOCK_INIT(sc);
371 
372 	return (0);
373 }
374 
375 int
376 gpiobus_alloc_ivars(struct gpiobus_ivar *devi)
377 {
378 
379 	/* Allocate pins and flags memory. */
380 	devi->pins = malloc(sizeof(uint32_t) * devi->npins, M_DEVBUF,
381 	    M_NOWAIT | M_ZERO);
382 	if (devi->pins == NULL)
383 		return (ENOMEM);
384 	return (0);
385 }
386 
387 void
388 gpiobus_free_ivars(struct gpiobus_ivar *devi)
389 {
390 
391 	if (devi->pins) {
392 		free(devi->pins, M_DEVBUF);
393 		devi->pins = NULL;
394 	}
395 	devi->npins = 0;
396 }
397 
398 int
399 gpiobus_acquire_pin(device_t bus, uint32_t pin)
400 {
401 	struct gpiobus_softc *sc;
402 
403 	sc = device_get_softc(bus);
404 	/* Consistency check. */
405 	if (pin >= sc->sc_npins) {
406 		panic("%s: invalid pin %d, max: %d",
407 		    device_get_nameunit(bus), pin, sc->sc_npins - 1);
408 	}
409 	/* Mark pin as mapped and give warning if it's already mapped. */
410 	if (sc->sc_pins[pin].mapped) {
411 		device_printf(bus, "warning: pin %d is already mapped\n", pin);
412 		return (EBUSY);
413 	}
414 	sc->sc_pins[pin].mapped = 1;
415 
416 	return (0);
417 }
418 
419 /* Release mapped pin */
420 void
421 gpiobus_release_pin(device_t bus, uint32_t pin)
422 {
423 	struct gpiobus_softc *sc;
424 
425 	sc = device_get_softc(bus);
426 	/* Consistency check. */
427 	if (pin >= sc->sc_npins) {
428 		panic("%s: invalid pin %d, max: %d",
429 		    device_get_nameunit(bus), pin, sc->sc_npins - 1);
430 	}
431 
432 	if (!sc->sc_pins[pin].mapped)
433 		panic("%s: pin %d is not mapped", device_get_nameunit(bus),
434 		    pin);
435 
436 	sc->sc_pins[pin].mapped = 0;
437 }
438 
439 static int
440 gpiobus_acquire_child_pins(device_t dev, device_t child)
441 {
442 	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
443 	int i;
444 
445 	for (i = 0; i < devi->npins; i++) {
446 		/* Reserve the GPIO pin. */
447 		if (gpiobus_acquire_pin(dev, devi->pins[i]) != 0) {
448 			device_printf(child, "cannot acquire pin %d\n",
449 			    devi->pins[i]);
450 			while (--i >= 0) {
451 				gpiobus_release_pin(dev, 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 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_identify_children(dev);
570 	bus_enumerate_hinted_children(dev);
571 
572 	bus_attach_children(dev);
573 	return (0);
574 }
575 
576 /*
577  * Since this is not a self-enumerating bus, and since we always add
578  * children in attach, we have to always delete children here.
579  */
580 int
581 gpiobus_detach(device_t dev)
582 {
583 	struct gpiobus_softc *sc;
584 	int i, err;
585 
586 	sc = GPIOBUS_SOFTC(dev);
587 	KASSERT(mtx_initialized(&sc->sc_mtx),
588 	    ("gpiobus mutex not initialized"));
589 	GPIOBUS_LOCK_DESTROY(sc);
590 
591 	if ((err = bus_detach_children(dev)) != 0)
592 		return (err);
593 
594 	rman_fini(&sc->sc_intr_rman);
595 	if (sc->sc_pins) {
596 		for (i = 0; i < sc->sc_npins; i++) {
597 			if (sc->sc_pins[i].name != NULL)
598 				free(sc->sc_pins[i].name, M_DEVBUF);
599 			sc->sc_pins[i].name = NULL;
600 		}
601 		free(sc->sc_pins, M_DEVBUF);
602 		sc->sc_pins = NULL;
603 	}
604 
605 	return (0);
606 }
607 
608 static int
609 gpiobus_suspend(device_t dev)
610 {
611 
612 	return (bus_generic_suspend(dev));
613 }
614 
615 static int
616 gpiobus_resume(device_t dev)
617 {
618 
619 	return (bus_generic_resume(dev));
620 }
621 
622 static void
623 gpiobus_probe_nomatch(device_t dev, device_t child)
624 {
625 	char pins[128];
626 	struct sbuf sb;
627 	struct gpiobus_ivar *devi;
628 
629 	devi = GPIOBUS_IVAR(child);
630 	sbuf_new(&sb, pins, sizeof(pins), SBUF_FIXEDLEN);
631 	gpiobus_print_pins(devi, &sb);
632 	sbuf_finish(&sb);
633 	device_printf(dev, "<unknown device> at pin%s %s",
634 	    devi->npins > 1 ? "s" : "", sbuf_data(&sb));
635 	resource_list_print_type(&devi->rl, "irq", SYS_RES_IRQ, "%jd");
636 	printf("\n");
637 }
638 
639 static int
640 gpiobus_print_child(device_t dev, device_t child)
641 {
642 	char pins[128];
643 	struct sbuf sb;
644 	int retval = 0;
645 	struct gpiobus_ivar *devi;
646 
647 	devi = GPIOBUS_IVAR(child);
648 	retval += bus_print_child_header(dev, child);
649 	if (devi->npins > 0) {
650 		if (devi->npins > 1)
651 			retval += printf(" at pins ");
652 		else
653 			retval += printf(" at pin ");
654 		sbuf_new(&sb, pins, sizeof(pins), SBUF_FIXEDLEN);
655 		gpiobus_print_pins(devi, &sb);
656 		sbuf_finish(&sb);
657 		retval += printf("%s", sbuf_data(&sb));
658 	}
659 	resource_list_print_type(&devi->rl, "irq", SYS_RES_IRQ, "%jd");
660 	retval += bus_print_child_footer(dev, child);
661 
662 	return (retval);
663 }
664 
665 static int
666 gpiobus_child_location(device_t bus, device_t child, struct sbuf *sb)
667 {
668 	struct gpiobus_ivar *devi;
669 
670 	devi = GPIOBUS_IVAR(child);
671 	sbuf_printf(sb, "pins=");
672 	gpiobus_print_pins(devi, sb);
673 
674 	return (0);
675 }
676 
677 static device_t
678 gpiobus_add_child(device_t dev, u_int order, const char *name, int unit)
679 {
680 	device_t child;
681 	struct gpiobus_ivar *devi;
682 
683 	child = device_add_child_ordered(dev, order, name, unit);
684 	if (child == NULL)
685 		return (child);
686 	devi = malloc(sizeof(struct gpiobus_ivar), M_DEVBUF, M_NOWAIT | M_ZERO);
687 	if (devi == NULL) {
688 		device_delete_child(dev, child);
689 		return (NULL);
690 	}
691 	resource_list_init(&devi->rl);
692 	device_set_ivars(child, devi);
693 
694 	return (child);
695 }
696 
697 static void
698 gpiobus_child_deleted(device_t dev, device_t child)
699 {
700 	struct gpiobus_ivar *devi;
701 
702 	devi = GPIOBUS_IVAR(child);
703 	if (devi == NULL)
704 		return;
705 	gpiobus_free_ivars(devi);
706 	resource_list_free(&devi->rl);
707 	free(devi, M_DEVBUF);
708 }
709 
710 static int
711 gpiobus_rescan(device_t dev)
712 {
713 
714 	/*
715 	 * Re-scan is supposed to remove and add children, but if someone has
716 	 * deleted the hints for a child we attached earlier, we have no easy
717 	 * way to handle that.  So this just attaches new children for whom new
718 	 * hints or drivers have arrived since we last tried.
719 	 */
720 	bus_enumerate_hinted_children(dev);
721 	bus_attach_children(dev);
722 	return (0);
723 }
724 
725 static void
726 gpiobus_hinted_child(device_t bus, const char *dname, int dunit)
727 {
728 	struct gpiobus_softc *sc = GPIOBUS_SOFTC(bus);
729 	device_t child;
730 	const char *pins;
731 	int irq, pinmask;
732 
733 	if (device_find_child(bus, dname, dunit) != NULL) {
734 		return;
735 	}
736 
737 	child = BUS_ADD_CHILD(bus, 0, dname, dunit);
738 	if (resource_int_value(dname, dunit, "pins", &pinmask) == 0) {
739 		if (gpiobus_parse_pins(sc, child, pinmask)) {
740 			device_delete_child(bus, child);
741 			return;
742 		}
743 	}
744 	else if (resource_string_value(dname, dunit, "pin_list", &pins) == 0) {
745 		if (gpiobus_parse_pin_list(sc, child, pins)) {
746 			device_delete_child(bus, child);
747 			return;
748 		}
749 	}
750 	if (resource_int_value(dname, dunit, "irq", &irq) == 0) {
751 		if (bus_set_resource(child, SYS_RES_IRQ, 0, irq, 1) != 0)
752 			device_printf(bus,
753 			    "warning: bus_set_resource() failed\n");
754 	}
755 }
756 
757 int
758 gpiobus_read_ivar(device_t dev, device_t child, int which, uintptr_t *result)
759 {
760 	struct gpiobus_ivar *devi;
761 
762 	devi = GPIOBUS_IVAR(child);
763         switch (which) {
764 	case GPIOBUS_IVAR_NPINS:
765 		*result = devi->npins;
766 		break;
767 	case GPIOBUS_IVAR_PINS:
768 		/* Children do not ever need to directly examine this. */
769 		return (ENOTSUP);
770         default:
771                 return (ENOENT);
772         }
773 
774 	return (0);
775 }
776 
777 static int
778 gpiobus_write_ivar(device_t dev, device_t child, int which, uintptr_t value)
779 {
780 	struct gpiobus_ivar *devi;
781 	const uint32_t *ptr;
782 	int i;
783 
784 	devi = GPIOBUS_IVAR(child);
785         switch (which) {
786 	case GPIOBUS_IVAR_NPINS:
787 		/* GPIO ivars are set once. */
788 		if (devi->npins != 0) {
789 			return (EBUSY);
790 		}
791 		devi->npins = value;
792 		if (gpiobus_alloc_ivars(devi) != 0) {
793 			device_printf(child, "cannot allocate device ivars\n");
794 			devi->npins = 0;
795 			return (ENOMEM);
796 		}
797 		break;
798 	case GPIOBUS_IVAR_PINS:
799 		ptr = (const uint32_t *)value;
800 		for (i = 0; i < devi->npins; i++)
801 			devi->pins[i] = ptr[i];
802 		if (gpiobus_acquire_child_pins(dev, child) != 0)
803 			return (EBUSY);
804 		break;
805         default:
806                 return (ENOENT);
807         }
808 
809         return (0);
810 }
811 
812 static struct rman *
813 gpiobus_get_rman(device_t bus, int type, u_int flags)
814 {
815 	struct gpiobus_softc *sc;
816 
817 	sc = device_get_softc(bus);
818 	switch (type) {
819 	case SYS_RES_IRQ:
820 		return (&sc->sc_intr_rman);
821 	default:
822 		return (NULL);
823 	}
824 }
825 
826 static struct resource *
827 gpiobus_alloc_resource(device_t bus, device_t child, int type, int *rid,
828     rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
829 {
830 	struct resource_list *rl;
831 	struct resource_list_entry *rle;
832 	int isdefault;
833 
834 	isdefault = (RMAN_IS_DEFAULT_RANGE(start, end) && count == 1);
835 	if (isdefault) {
836 		rl = BUS_GET_RESOURCE_LIST(bus, child);
837 		if (rl == NULL)
838 			return (NULL);
839 		rle = resource_list_find(rl, type, *rid);
840 		if (rle == NULL)
841 			return (NULL);
842 		start = rle->start;
843 		count = rle->count;
844 		end = rle->end;
845 	}
846 	return (bus_generic_rman_alloc_resource(bus, child, type, rid, start,
847 	    end, count, flags));
848 }
849 
850 static int
851 gpiobus_release_resource(device_t dev, device_t child, struct resource *r)
852 {
853 	int err;
854 #ifdef INTRNG
855 	u_int irq;
856 
857 	irq = rman_get_start(r);
858 	MPASS(irq == rman_get_end(r));
859 #endif
860 	err = bus_generic_rman_release_resource(dev, child, r);
861 	if (err != 0)
862 		return (err);
863 #ifdef INTRNG
864 	intr_unmap_irq(irq);
865 #endif
866 	return (0);
867 }
868 
869 static struct resource_list *
870 gpiobus_get_resource_list(device_t bus __unused, device_t child)
871 {
872 	struct gpiobus_ivar *ivar;
873 
874 	ivar = GPIOBUS_IVAR(child);
875 
876 	return (&ivar->rl);
877 }
878 
879 static int
880 gpiobus_acquire_bus(device_t busdev, device_t child, int how)
881 {
882 	struct gpiobus_softc *sc;
883 
884 	sc = device_get_softc(busdev);
885 	GPIOBUS_ASSERT_UNLOCKED(sc);
886 	GPIOBUS_LOCK(sc);
887 	if (sc->sc_owner != NULL) {
888 		if (sc->sc_owner == child)
889 			panic("%s: %s still owns the bus.",
890 			    device_get_nameunit(busdev),
891 			    device_get_nameunit(child));
892 		if (how == GPIOBUS_DONTWAIT) {
893 			GPIOBUS_UNLOCK(sc);
894 			return (EWOULDBLOCK);
895 		}
896 		while (sc->sc_owner != NULL)
897 			mtx_sleep(sc, &sc->sc_mtx, 0, "gpiobuswait", 0);
898 	}
899 	sc->sc_owner = child;
900 	GPIOBUS_UNLOCK(sc);
901 
902 	return (0);
903 }
904 
905 static void
906 gpiobus_release_bus(device_t busdev, device_t child)
907 {
908 	struct gpiobus_softc *sc;
909 
910 	sc = device_get_softc(busdev);
911 	GPIOBUS_ASSERT_UNLOCKED(sc);
912 	GPIOBUS_LOCK(sc);
913 	if (sc->sc_owner == NULL)
914 		panic("%s: %s releasing unowned bus.",
915 		    device_get_nameunit(busdev),
916 		    device_get_nameunit(child));
917 	if (sc->sc_owner != child)
918 		panic("%s: %s trying to release bus owned by %s",
919 		    device_get_nameunit(busdev),
920 		    device_get_nameunit(child),
921 		    device_get_nameunit(sc->sc_owner));
922 	sc->sc_owner = NULL;
923 	wakeup(sc);
924 	GPIOBUS_UNLOCK(sc);
925 }
926 
927 static int
928 gpiobus_pin_setflags(device_t dev, device_t child, uint32_t pin,
929     uint32_t flags)
930 {
931 	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
932 	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
933 	uint32_t caps;
934 
935 	if (pin >= devi->npins)
936 		return (EINVAL);
937 	if (GPIO_PIN_GETCAPS(sc->sc_dev, devi->pins[pin], &caps) != 0)
938 		return (EINVAL);
939 	if (gpio_check_flags(caps, flags) != 0)
940 		return (EINVAL);
941 
942 	return (GPIO_PIN_SETFLAGS(sc->sc_dev, devi->pins[pin], flags));
943 }
944 
945 static int
946 gpiobus_pin_getflags(device_t dev, device_t child, uint32_t pin,
947     uint32_t *flags)
948 {
949 	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
950 	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
951 
952 	if (pin >= devi->npins)
953 		return (EINVAL);
954 
955 	return GPIO_PIN_GETFLAGS(sc->sc_dev, devi->pins[pin], flags);
956 }
957 
958 static int
959 gpiobus_pin_getcaps(device_t dev, device_t child, uint32_t pin,
960     uint32_t *caps)
961 {
962 	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
963 	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
964 
965 	if (pin >= devi->npins)
966 		return (EINVAL);
967 
968 	return GPIO_PIN_GETCAPS(sc->sc_dev, devi->pins[pin], caps);
969 }
970 
971 static int
972 gpiobus_pin_set(device_t dev, device_t child, uint32_t pin,
973     unsigned int value)
974 {
975 	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
976 	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
977 
978 	if (pin >= devi->npins)
979 		return (EINVAL);
980 
981 	return GPIO_PIN_SET(sc->sc_dev, devi->pins[pin], value);
982 }
983 
984 static int
985 gpiobus_pin_get(device_t dev, device_t child, uint32_t pin,
986     unsigned int *value)
987 {
988 	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
989 	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
990 
991 	if (pin >= devi->npins)
992 		return (EINVAL);
993 
994 	return GPIO_PIN_GET(sc->sc_dev, devi->pins[pin], value);
995 }
996 
997 static int
998 gpiobus_pin_toggle(device_t dev, device_t child, uint32_t pin)
999 {
1000 	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
1001 	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
1002 
1003 	if (pin >= devi->npins)
1004 		return (EINVAL);
1005 
1006 	return GPIO_PIN_TOGGLE(sc->sc_dev, devi->pins[pin]);
1007 }
1008 
1009 static int
1010 gpiobus_pin_getname(device_t dev, uint32_t pin, char *name)
1011 {
1012 	struct gpiobus_softc *sc;
1013 
1014 	sc = GPIOBUS_SOFTC(dev);
1015 	if (pin > sc->sc_npins)
1016 		return (EINVAL);
1017 	/* Did we have a name for this pin ? */
1018 	if (sc->sc_pins[pin].name != NULL) {
1019 		memcpy(name, sc->sc_pins[pin].name, GPIOMAXNAME);
1020 		return (0);
1021 	}
1022 
1023 	/* Return the default pin name. */
1024 	return (GPIO_PIN_GETNAME(device_get_parent(dev), pin, name));
1025 }
1026 
1027 static int
1028 gpiobus_pin_setname(device_t dev, uint32_t pin, const char *name)
1029 {
1030 	struct gpiobus_softc *sc;
1031 
1032 	sc = GPIOBUS_SOFTC(dev);
1033 	if (pin > sc->sc_npins)
1034 		return (EINVAL);
1035 	if (name == NULL)
1036 		return (EINVAL);
1037 	/* Save the pin name. */
1038 	if (sc->sc_pins[pin].name == NULL)
1039 		sc->sc_pins[pin].name = malloc(GPIOMAXNAME, M_DEVBUF,
1040 		    M_WAITOK | M_ZERO);
1041 	strlcpy(sc->sc_pins[pin].name, name, GPIOMAXNAME);
1042 
1043 	return (0);
1044 }
1045 
1046 static device_method_t gpiobus_methods[] = {
1047 	/* Device interface */
1048 	DEVMETHOD(device_probe,		gpiobus_probe),
1049 	DEVMETHOD(device_attach,	gpiobus_attach),
1050 	DEVMETHOD(device_detach,	gpiobus_detach),
1051 	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
1052 	DEVMETHOD(device_suspend,	gpiobus_suspend),
1053 	DEVMETHOD(device_resume,	gpiobus_resume),
1054 
1055 	/* Bus interface */
1056 	DEVMETHOD(bus_setup_intr,	bus_generic_setup_intr),
1057 	DEVMETHOD(bus_config_intr,	bus_generic_config_intr),
1058 	DEVMETHOD(bus_teardown_intr,	bus_generic_teardown_intr),
1059 	DEVMETHOD(bus_delete_resource,	bus_generic_rl_delete_resource),
1060 	DEVMETHOD(bus_get_resource,	bus_generic_rl_get_resource),
1061 	DEVMETHOD(bus_set_resource,	bus_generic_rl_set_resource),
1062 	DEVMETHOD(bus_alloc_resource,	gpiobus_alloc_resource),
1063 	DEVMETHOD(bus_release_resource,	gpiobus_release_resource),
1064 	DEVMETHOD(bus_activate_resource,	bus_generic_rman_activate_resource),
1065 	DEVMETHOD(bus_deactivate_resource,	bus_generic_rman_deactivate_resource),
1066 	DEVMETHOD(bus_get_resource_list,	gpiobus_get_resource_list),
1067 	DEVMETHOD(bus_get_rman,		gpiobus_get_rman),
1068 	DEVMETHOD(bus_add_child,	gpiobus_add_child),
1069 	DEVMETHOD(bus_child_deleted,	gpiobus_child_deleted),
1070 	DEVMETHOD(bus_rescan,		gpiobus_rescan),
1071 	DEVMETHOD(bus_probe_nomatch,	gpiobus_probe_nomatch),
1072 	DEVMETHOD(bus_print_child,	gpiobus_print_child),
1073 	DEVMETHOD(bus_child_location,	gpiobus_child_location),
1074 	DEVMETHOD(bus_hinted_child,	gpiobus_hinted_child),
1075 	DEVMETHOD(bus_read_ivar,        gpiobus_read_ivar),
1076 	DEVMETHOD(bus_write_ivar,       gpiobus_write_ivar),
1077 
1078 	/* GPIO protocol */
1079 	DEVMETHOD(gpiobus_acquire_bus,	gpiobus_acquire_bus),
1080 	DEVMETHOD(gpiobus_release_bus,	gpiobus_release_bus),
1081 	DEVMETHOD(gpiobus_pin_getflags,	gpiobus_pin_getflags),
1082 	DEVMETHOD(gpiobus_pin_getcaps,	gpiobus_pin_getcaps),
1083 	DEVMETHOD(gpiobus_pin_setflags,	gpiobus_pin_setflags),
1084 	DEVMETHOD(gpiobus_pin_get,	gpiobus_pin_get),
1085 	DEVMETHOD(gpiobus_pin_set,	gpiobus_pin_set),
1086 	DEVMETHOD(gpiobus_pin_toggle,	gpiobus_pin_toggle),
1087 	DEVMETHOD(gpiobus_pin_getname,	gpiobus_pin_getname),
1088 	DEVMETHOD(gpiobus_pin_setname,	gpiobus_pin_setname),
1089 
1090 	DEVMETHOD_END
1091 };
1092 
1093 driver_t gpiobus_driver = {
1094 	"gpiobus",
1095 	gpiobus_methods,
1096 	sizeof(struct gpiobus_softc)
1097 };
1098 
1099 EARLY_DRIVER_MODULE(gpiobus, gpio, gpiobus_driver, 0, 0,
1100     BUS_PASS_BUS + BUS_PASS_ORDER_MIDDLE);
1101 MODULE_VERSION(gpiobus, 1);
1102