xref: /freebsd/sys/dev/gpio/gpiobus.c (revision 186100f13bd255260a74b61184f424d0851ee6ec)
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 device_t gpiobus_add_child(device_t, u_int, const char *, int);
61 static void gpiobus_hinted_child(device_t, const char *, int);
62 
63 /*
64  * GPIOBUS interface
65  */
66 static int gpiobus_acquire_bus(device_t, device_t, int);
67 static void gpiobus_release_bus(device_t, device_t);
68 static int gpiobus_pin_setflags(device_t, device_t, uint32_t, uint32_t);
69 static int gpiobus_pin_getflags(device_t, device_t, uint32_t, uint32_t*);
70 static int gpiobus_pin_getcaps(device_t, device_t, uint32_t, uint32_t*);
71 static int gpiobus_pin_set(device_t, device_t, uint32_t, unsigned int);
72 static int gpiobus_pin_get(device_t, device_t, uint32_t, unsigned int*);
73 static int gpiobus_pin_toggle(device_t, device_t, uint32_t);
74 
75 /*
76  * gpiobus_pin flags
77  *  The flags in struct gpiobus_pin are not related to the flags used by the
78  *  low-level controller driver in struct gpio_pin.  Currently, only pins
79  *  acquired via FDT data have gpiobus_pin.flags set, sourced from the flags in
80  *  the FDT properties.  In theory, these flags are defined per-platform.  In
81  *  practice they are always the flags from the dt-bindings/gpio/gpio.h file.
82  *  The only one of those flags we currently support is for handling active-low
83  *  pins, so we just define that flag here instead of including a GPL'd header.
84  */
85 #define	GPIO_ACTIVE_LOW 1
86 
87 /*
88  * XXX -> Move me to better place - gpio_subr.c?
89  * Also, this function must be changed when interrupt configuration
90  * data will be moved into struct resource.
91  */
92 #ifdef INTRNG
93 
94 struct resource *
gpio_alloc_intr_resource(device_t consumer_dev,int * rid,u_int alloc_flags,gpio_pin_t pin,uint32_t intr_mode)95 gpio_alloc_intr_resource(device_t consumer_dev, int *rid, u_int alloc_flags,
96     gpio_pin_t pin, uint32_t intr_mode)
97 {
98 	u_int irq;
99 	struct intr_map_data_gpio *gpio_data;
100 	struct resource *res;
101 
102 	gpio_data = (struct intr_map_data_gpio *)intr_alloc_map_data(
103 	    INTR_MAP_DATA_GPIO, sizeof(*gpio_data), M_WAITOK | M_ZERO);
104 	gpio_data->gpio_pin_num = pin->pin;
105 	gpio_data->gpio_pin_flags = pin->flags;
106 	gpio_data->gpio_intr_mode = intr_mode;
107 
108 	irq = intr_map_irq(pin->dev, 0, (struct intr_map_data *)gpio_data);
109 	res = bus_alloc_resource(consumer_dev, SYS_RES_IRQ, rid, irq, irq, 1,
110 	    alloc_flags);
111 	if (res == NULL) {
112 		intr_unmap_irq(irq);
113 		return (NULL);
114 	}
115 	return (res);
116 }
117 #else
118 struct resource *
gpio_alloc_intr_resource(device_t consumer_dev,int * rid,u_int alloc_flags,gpio_pin_t pin,uint32_t intr_mode)119 gpio_alloc_intr_resource(device_t consumer_dev, int *rid, u_int alloc_flags,
120     gpio_pin_t pin, uint32_t intr_mode)
121 {
122 
123 	return (NULL);
124 }
125 #endif
126 
127 int
gpio_check_flags(uint32_t caps,uint32_t flags)128 gpio_check_flags(uint32_t caps, uint32_t flags)
129 {
130 
131 	/* Filter unwanted flags. */
132 	flags &= caps;
133 
134 	/* Cannot mix input/output together. */
135 	if (flags & GPIO_PIN_INPUT && flags & GPIO_PIN_OUTPUT)
136 		return (EINVAL);
137 	/* Cannot mix pull-up/pull-down together. */
138 	if (flags & GPIO_PIN_PULLUP && flags & GPIO_PIN_PULLDOWN)
139 		return (EINVAL);
140 	/* Cannot mix output and interrupt flags together */
141 	if (flags & GPIO_PIN_OUTPUT && flags & GPIO_INTR_MASK)
142 		return (EINVAL);
143 	/* Only one interrupt flag can be defined at once */
144 	if ((flags & GPIO_INTR_MASK) & ((flags & GPIO_INTR_MASK) - 1))
145 		return (EINVAL);
146 	/* The interrupt attached flag cannot be set */
147 	if (flags & GPIO_INTR_ATTACHED)
148 		return (EINVAL);
149 
150 	return (0);
151 }
152 
153 int
gpio_pin_get_by_bus_pinnum(device_t busdev,uint32_t pinnum,gpio_pin_t * ppin)154 gpio_pin_get_by_bus_pinnum(device_t busdev, uint32_t pinnum, gpio_pin_t *ppin)
155 {
156 	gpio_pin_t pin;
157 	int err;
158 
159 	err = gpiobus_acquire_pin(busdev, pinnum);
160 	if (err != 0)
161 		return (EBUSY);
162 
163 	pin = malloc(sizeof(*pin), M_DEVBUF, M_WAITOK | M_ZERO);
164 
165 	pin->dev = device_get_parent(busdev);
166 	pin->pin = pinnum;
167 	pin->flags = 0;
168 
169 	*ppin = pin;
170 	return (0);
171 }
172 
173 int
gpio_pin_get_by_child_index(device_t childdev,uint32_t idx,gpio_pin_t * ppin)174 gpio_pin_get_by_child_index(device_t childdev, uint32_t idx, gpio_pin_t *ppin)
175 {
176 	struct gpiobus_ivar *devi;
177 
178 	devi = GPIOBUS_IVAR(childdev);
179 	if (idx >= devi->npins)
180 		return (EINVAL);
181 
182 	return (gpio_pin_get_by_bus_pinnum(device_get_parent(childdev),
183 	    devi->pins[idx], ppin));
184 }
185 
186 int
gpio_pin_getcaps(gpio_pin_t pin,uint32_t * caps)187 gpio_pin_getcaps(gpio_pin_t pin, uint32_t *caps)
188 {
189 
190 	KASSERT(pin != NULL, ("GPIO pin is NULL."));
191 	KASSERT(pin->dev != NULL, ("GPIO pin device is NULL."));
192 	return (GPIO_PIN_GETCAPS(pin->dev, pin->pin, caps));
193 }
194 
195 int
gpio_pin_is_active(gpio_pin_t pin,bool * active)196 gpio_pin_is_active(gpio_pin_t pin, bool *active)
197 {
198 	int rv;
199 	uint32_t tmp;
200 
201 	KASSERT(pin != NULL, ("GPIO pin is NULL."));
202 	KASSERT(pin->dev != NULL, ("GPIO pin device is NULL."));
203 	rv = GPIO_PIN_GET(pin->dev, pin->pin, &tmp);
204 	if (rv  != 0) {
205 		return (rv);
206 	}
207 
208 	if (pin->flags & GPIO_ACTIVE_LOW)
209 		*active = tmp == 0;
210 	else
211 		*active = tmp != 0;
212 	return (0);
213 }
214 
215 /*
216  * Note that this function should only
217  * be used in cases where a pre-existing
218  * gpiobus_pin structure exists. In most
219  * cases, the gpio_pin_get_by_* functions
220  * suffice.
221  */
222 int
gpio_pin_acquire(gpio_pin_t gpio)223 gpio_pin_acquire(gpio_pin_t gpio)
224 {
225 	device_t busdev;
226 
227 	KASSERT(gpio != NULL, ("GPIO pin is NULL."));
228 	KASSERT(gpio->dev != NULL, ("GPIO pin device is NULL."));
229 
230 	busdev = GPIO_GET_BUS(gpio->dev);
231 	if (busdev == NULL)
232 		return (ENXIO);
233 
234 	return (gpiobus_acquire_pin(busdev, gpio->pin));
235 }
236 
237 void
gpio_pin_release(gpio_pin_t gpio)238 gpio_pin_release(gpio_pin_t gpio)
239 {
240 	device_t busdev;
241 
242 	KASSERT(gpio != NULL, ("GPIO pin is NULL."));
243 	KASSERT(gpio->dev != NULL, ("GPIO pin device is NULL."));
244 
245 	busdev = GPIO_GET_BUS(gpio->dev);
246 	KASSERT(busdev != NULL, ("gpiobus dev is NULL."));
247 
248 	gpiobus_release_pin(busdev, gpio->pin);
249 	free(gpio, M_DEVBUF);
250 }
251 
252 int
gpio_pin_set_active(gpio_pin_t pin,bool active)253 gpio_pin_set_active(gpio_pin_t pin, bool active)
254 {
255 	int rv;
256 	uint32_t tmp;
257 
258 	if (pin->flags & GPIO_ACTIVE_LOW)
259 		tmp = active ? 0 : 1;
260 	else
261 		tmp = active ? 1 : 0;
262 
263 	KASSERT(pin != NULL, ("GPIO pin is NULL."));
264 	KASSERT(pin->dev != NULL, ("GPIO pin device is NULL."));
265 	rv = GPIO_PIN_SET(pin->dev, pin->pin, tmp);
266 	return (rv);
267 }
268 
269 int
gpio_pin_setflags(gpio_pin_t pin,uint32_t flags)270 gpio_pin_setflags(gpio_pin_t pin, uint32_t flags)
271 {
272 	int rv;
273 
274 	KASSERT(pin != NULL, ("GPIO pin is NULL."));
275 	KASSERT(pin->dev != NULL, ("GPIO pin device is NULL."));
276 
277 	rv = GPIO_PIN_SETFLAGS(pin->dev, pin->pin, flags);
278 	return (rv);
279 }
280 
281 static void
gpiobus_print_pins(struct gpiobus_ivar * devi,struct sbuf * sb)282 gpiobus_print_pins(struct gpiobus_ivar *devi, struct sbuf *sb)
283 {
284 	int i, range_start, range_stop, need_coma;
285 
286 	if (devi->npins == 0)
287 		return;
288 
289 	need_coma = 0;
290 	range_start = range_stop = devi->pins[0];
291 	for (i = 1; i < devi->npins; i++) {
292 		if (devi->pins[i] != (range_stop + 1)) {
293 			if (need_coma)
294 				sbuf_cat(sb, ",");
295 			if (range_start != range_stop)
296 				sbuf_printf(sb, "%d-%d", range_start, range_stop);
297 			else
298 				sbuf_printf(sb, "%d", range_start);
299 			range_start = range_stop = devi->pins[i];
300 			need_coma = 1;
301 		}
302 		else
303 			range_stop++;
304 	}
305 
306 	if (need_coma)
307 		sbuf_cat(sb, ",");
308 	if (range_start != range_stop)
309 		sbuf_printf(sb, "%d-%d", range_start, range_stop);
310 	else
311 		sbuf_printf(sb, "%d", range_start);
312 }
313 
314 device_t
gpiobus_add_bus(device_t dev)315 gpiobus_add_bus(device_t dev)
316 {
317 	device_t busdev;
318 
319 	busdev = device_add_child(dev, "gpiobus", DEVICE_UNIT_ANY);
320 	if (busdev == NULL)
321 		return (NULL);
322 #ifdef FDT
323 	ofw_gpiobus_register_provider(dev);
324 #endif
325 	return (busdev);
326 }
327 
328 int
gpiobus_detach_bus(device_t dev)329 gpiobus_detach_bus(device_t dev)
330 {
331 #ifdef FDT
332 	ofw_gpiobus_unregister_provider(dev);
333 #endif
334 	return (bus_generic_detach(dev));
335 }
336 
337 int
gpiobus_init_softc(device_t dev)338 gpiobus_init_softc(device_t dev)
339 {
340 	struct gpiobus_softc *sc;
341 
342 	sc = GPIOBUS_SOFTC(dev);
343 	sc->sc_busdev = dev;
344 	sc->sc_dev = device_get_parent(dev);
345 	sc->sc_intr_rman.rm_type = RMAN_ARRAY;
346 	sc->sc_intr_rman.rm_descr = "GPIO Interrupts";
347 	if (rman_init(&sc->sc_intr_rman) != 0 ||
348 	    rman_manage_region(&sc->sc_intr_rman, 0, ~0) != 0)
349 		panic("%s: failed to set up rman.", __func__);
350 
351 	if (GPIO_PIN_MAX(sc->sc_dev, &sc->sc_npins) != 0)
352 		return (ENXIO);
353 
354 	KASSERT(sc->sc_npins >= 0, ("GPIO device with no pins"));
355 
356 	/* Pins = GPIO_PIN_MAX() + 1 */
357 	sc->sc_npins++;
358 
359 	sc->sc_pins = malloc(sizeof(*sc->sc_pins) * sc->sc_npins, M_DEVBUF,
360 	    M_NOWAIT | M_ZERO);
361 	if (sc->sc_pins == NULL)
362 		return (ENOMEM);
363 
364 	/* Initialize the bus lock. */
365 	GPIOBUS_LOCK_INIT(sc);
366 
367 	return (0);
368 }
369 
370 int
gpiobus_add_gpioc(device_t dev)371 gpiobus_add_gpioc(device_t dev)
372 {
373 	struct gpiobus_ivar *devi;
374 	struct gpiobus_softc *sc;
375 	device_t gpioc;
376 	int err;
377 
378 	gpioc = BUS_ADD_CHILD(dev, 0, "gpioc", DEVICE_UNIT_ANY);
379 	if (gpioc == NULL)
380 		return (ENXIO);
381 
382 	sc = device_get_softc(dev);
383 	devi = device_get_ivars(gpioc);
384 
385 	devi->npins = sc->sc_npins;
386 	err = gpiobus_alloc_ivars(devi);
387 	if (err != 0) {
388 		device_delete_child(dev, gpioc);
389 		return (err);
390 	}
391 
392 	err = GPIO_GET_PIN_LIST(sc->sc_dev, devi->pins);
393 	if (err != 0) {
394 		device_delete_child(dev, gpioc);
395 		gpiobus_free_ivars(devi);
396 	}
397 
398 	return (err);
399 }
400 
401 int
gpiobus_alloc_ivars(struct gpiobus_ivar * devi)402 gpiobus_alloc_ivars(struct gpiobus_ivar *devi)
403 {
404 
405 	/* Allocate pins and flags memory. */
406 	devi->pins = malloc(sizeof(uint32_t) * devi->npins, M_DEVBUF,
407 	    M_NOWAIT | M_ZERO);
408 	if (devi->pins == NULL)
409 		return (ENOMEM);
410 	return (0);
411 }
412 
413 void
gpiobus_free_ivars(struct gpiobus_ivar * devi)414 gpiobus_free_ivars(struct gpiobus_ivar *devi)
415 {
416 
417 	if (devi->pins) {
418 		free(devi->pins, M_DEVBUF);
419 		devi->pins = NULL;
420 	}
421 	devi->npins = 0;
422 }
423 
424 int
gpiobus_acquire_pin(device_t bus,uint32_t pin)425 gpiobus_acquire_pin(device_t bus, uint32_t pin)
426 {
427 	struct gpiobus_softc *sc;
428 
429 	sc = device_get_softc(bus);
430 	/* Consistency check. */
431 	if (pin >= sc->sc_npins) {
432 		panic("%s: invalid pin %d, max: %d",
433 		    device_get_nameunit(bus), pin, sc->sc_npins - 1);
434 	}
435 	/* Mark pin as mapped and give warning if it's already mapped. */
436 	if (sc->sc_pins[pin].mapped) {
437 		device_printf(bus, "warning: pin %d is already mapped\n", pin);
438 		return (EBUSY);
439 	}
440 	sc->sc_pins[pin].mapped = 1;
441 
442 	return (0);
443 }
444 
445 /* Release mapped pin */
446 void
gpiobus_release_pin(device_t bus,uint32_t pin)447 gpiobus_release_pin(device_t bus, uint32_t pin)
448 {
449 	struct gpiobus_softc *sc;
450 
451 	sc = device_get_softc(bus);
452 	/* Consistency check. */
453 	if (pin >= sc->sc_npins) {
454 		panic("%s: invalid pin %d, max: %d",
455 		    device_get_nameunit(bus), pin, sc->sc_npins - 1);
456 	}
457 
458 	if (!sc->sc_pins[pin].mapped)
459 		panic("%s: pin %d is not mapped", device_get_nameunit(bus),
460 		    pin);
461 
462 	sc->sc_pins[pin].mapped = 0;
463 }
464 
465 static int
gpiobus_acquire_child_pins(device_t dev,device_t child)466 gpiobus_acquire_child_pins(device_t dev, device_t child)
467 {
468 	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
469 	int i;
470 
471 	for (i = 0; i < devi->npins; i++) {
472 		/* Reserve the GPIO pin. */
473 		if (gpiobus_acquire_pin(dev, devi->pins[i]) != 0) {
474 			device_printf(child, "cannot acquire pin %d\n",
475 			    devi->pins[i]);
476 			while (--i >= 0) {
477 				gpiobus_release_pin(dev, devi->pins[i]);
478 			}
479 			gpiobus_free_ivars(devi);
480 			return (EBUSY);
481 		}
482 	}
483 	for (i = 0; i < devi->npins; i++) {
484 		/* Use the child name as pin name. */
485 		GPIOBUS_PIN_SETNAME(dev, devi->pins[i],
486 		    device_get_nameunit(child));
487 
488 	}
489 	return (0);
490 }
491 
492 static int
gpiobus_parse_pins(struct gpiobus_softc * sc,device_t child,int mask)493 gpiobus_parse_pins(struct gpiobus_softc *sc, device_t child, int mask)
494 {
495 	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
496 	int i, npins;
497 
498 	npins = 0;
499 	for (i = 0; i < 32; i++) {
500 		if (mask & (1 << i))
501 			npins++;
502 	}
503 	if (npins == 0) {
504 		device_printf(child, "empty pin mask\n");
505 		return (EINVAL);
506 	}
507 	devi->npins = npins;
508 	if (gpiobus_alloc_ivars(devi) != 0) {
509 		device_printf(child, "cannot allocate device ivars\n");
510 		return (EINVAL);
511 	}
512 	npins = 0;
513 	for (i = 0; i < 32; i++) {
514 		if ((mask & (1 << i)) == 0)
515 			continue;
516 		devi->pins[npins++] = i;
517 	}
518 
519 	return (0);
520 }
521 
522 static int
gpiobus_parse_pin_list(struct gpiobus_softc * sc,device_t child,const char * pins)523 gpiobus_parse_pin_list(struct gpiobus_softc *sc, device_t child,
524     const char *pins)
525 {
526 	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
527 	const char *p;
528 	char *endp;
529 	unsigned long pin;
530 	int i, npins;
531 
532 	npins = 0;
533 	p = pins;
534 	for (;;) {
535 		pin = strtoul(p, &endp, 0);
536 		if (endp == p)
537 			break;
538 		npins++;
539 		if (*endp == '\0')
540 			break;
541 		p = endp + 1;
542 	}
543 
544 	if (*endp != '\0') {
545 		device_printf(child, "garbage in the pin list: %s\n", endp);
546 		return (EINVAL);
547 	}
548 	if (npins == 0) {
549 		device_printf(child, "empty pin list\n");
550 		return (EINVAL);
551 	}
552 
553 	devi->npins = npins;
554 	if (gpiobus_alloc_ivars(devi) != 0) {
555 		device_printf(child, "cannot allocate device ivars\n");
556 		return (EINVAL);
557 	}
558 
559 	i = 0;
560 	p = pins;
561 	for (;;) {
562 		pin = strtoul(p, &endp, 0);
563 
564 		devi->pins[i] = pin;
565 
566 		if (*endp == '\0')
567 			break;
568 		i++;
569 		p = endp + 1;
570 	}
571 
572 	return (0);
573 }
574 
575 static int
gpiobus_probe(device_t dev)576 gpiobus_probe(device_t dev)
577 {
578 	device_set_desc(dev, "GPIO bus");
579 
580 	return (BUS_PROBE_GENERIC);
581 }
582 
583 int
gpiobus_attach(device_t dev)584 gpiobus_attach(device_t dev)
585 {
586 	int err;
587 
588 	err = gpiobus_init_softc(dev);
589 	if (err != 0)
590 		return (err);
591 
592 	err = gpiobus_add_gpioc(dev);
593 	if (err != 0)
594 		return (err);
595 
596 	/*
597 	 * Get parent's pins and mark them as unmapped
598 	 */
599 	bus_identify_children(dev);
600 	bus_enumerate_hinted_children(dev);
601 
602 	bus_attach_children(dev);
603 	return (0);
604 }
605 
606 /*
607  * Since this is not a self-enumerating bus, and since we always add
608  * children in attach, we have to always delete children here.
609  */
610 int
gpiobus_detach(device_t dev)611 gpiobus_detach(device_t dev)
612 {
613 	struct gpiobus_softc *sc;
614 	int i, err;
615 
616 	sc = GPIOBUS_SOFTC(dev);
617 	KASSERT(mtx_initialized(&sc->sc_mtx),
618 	    ("gpiobus mutex not initialized"));
619 	GPIOBUS_LOCK_DESTROY(sc);
620 
621 	if ((err = bus_detach_children(dev)) != 0)
622 		return (err);
623 
624 	rman_fini(&sc->sc_intr_rman);
625 	if (sc->sc_pins) {
626 		for (i = 0; i < sc->sc_npins; i++) {
627 			if (sc->sc_pins[i].name != NULL)
628 				free(sc->sc_pins[i].name, M_DEVBUF);
629 			sc->sc_pins[i].name = NULL;
630 		}
631 		free(sc->sc_pins, M_DEVBUF);
632 		sc->sc_pins = NULL;
633 	}
634 
635 	return (0);
636 }
637 
638 static int
gpiobus_suspend(device_t dev)639 gpiobus_suspend(device_t dev)
640 {
641 
642 	return (bus_generic_suspend(dev));
643 }
644 
645 static int
gpiobus_resume(device_t dev)646 gpiobus_resume(device_t dev)
647 {
648 
649 	return (bus_generic_resume(dev));
650 }
651 
652 static void
gpiobus_probe_nomatch(device_t dev,device_t child)653 gpiobus_probe_nomatch(device_t dev, device_t child)
654 {
655 	char pins[128];
656 	struct sbuf sb;
657 	struct gpiobus_ivar *devi;
658 
659 	devi = GPIOBUS_IVAR(child);
660 	sbuf_new(&sb, pins, sizeof(pins), SBUF_FIXEDLEN);
661 	gpiobus_print_pins(devi, &sb);
662 	sbuf_finish(&sb);
663 	device_printf(dev, "<unknown device> at pin%s %s",
664 	    devi->npins > 1 ? "s" : "", sbuf_data(&sb));
665 	resource_list_print_type(&devi->rl, "irq", SYS_RES_IRQ, "%jd");
666 	printf("\n");
667 }
668 
669 static int
gpiobus_print_child(device_t dev,device_t child)670 gpiobus_print_child(device_t dev, device_t child)
671 {
672 	char pins[128];
673 	struct sbuf sb;
674 	int retval = 0;
675 	struct gpiobus_ivar *devi;
676 
677 	devi = GPIOBUS_IVAR(child);
678 	retval += bus_print_child_header(dev, child);
679 	if (devi->npins > 0) {
680 		if (devi->npins > 1)
681 			retval += printf(" at pins ");
682 		else
683 			retval += printf(" at pin ");
684 		sbuf_new(&sb, pins, sizeof(pins), SBUF_FIXEDLEN);
685 		gpiobus_print_pins(devi, &sb);
686 		sbuf_finish(&sb);
687 		retval += printf("%s", sbuf_data(&sb));
688 	}
689 	resource_list_print_type(&devi->rl, "irq", SYS_RES_IRQ, "%jd");
690 	retval += bus_print_child_footer(dev, child);
691 
692 	return (retval);
693 }
694 
695 int
gpiobus_child_location(device_t bus,device_t child,struct sbuf * sb)696 gpiobus_child_location(device_t bus, device_t child, struct sbuf *sb)
697 {
698 	struct gpiobus_ivar *devi;
699 
700 	devi = GPIOBUS_IVAR(child);
701 	sbuf_printf(sb, "pins=");
702 	gpiobus_print_pins(devi, sb);
703 
704 	return (0);
705 }
706 
707 device_t
gpiobus_add_child_common(device_t dev,u_int order,const char * name,int unit,size_t ivars_size)708 gpiobus_add_child_common(device_t dev, u_int order, const char *name, int unit,
709     size_t ivars_size)
710 {
711 	device_t child;
712 	struct gpiobus_ivar *devi;
713 
714 	KASSERT(ivars_size >= sizeof(struct gpiobus_ivar),
715 	    ("child ivars must include gpiobus_ivar as their first member"));
716 	child = device_add_child_ordered(dev, order, name, unit);
717 	if (child == NULL)
718 		return (child);
719 	devi = malloc(ivars_size, M_DEVBUF, M_NOWAIT | M_ZERO);
720 	if (devi == NULL) {
721 		device_delete_child(dev, child);
722 		return (NULL);
723 	}
724 	resource_list_init(&devi->rl);
725 	device_set_ivars(child, devi);
726 
727 	return (child);
728 }
729 
730 static device_t
gpiobus_add_child(device_t dev,u_int order,const char * name,int unit)731 gpiobus_add_child(device_t dev, u_int order, const char *name, int unit)
732 {
733 	return (gpiobus_add_child_common(dev, order, name, unit,
734 	    sizeof(struct gpiobus_ivar)));
735 }
736 
737 static void
gpiobus_child_deleted(device_t dev,device_t child)738 gpiobus_child_deleted(device_t dev, device_t child)
739 {
740 	struct gpiobus_ivar *devi;
741 
742 	devi = GPIOBUS_IVAR(child);
743 	if (devi == NULL)
744 		return;
745 	gpiobus_free_ivars(devi);
746 	resource_list_free(&devi->rl);
747 	free(devi, M_DEVBUF);
748 }
749 
750 static int
gpiobus_rescan(device_t dev)751 gpiobus_rescan(device_t dev)
752 {
753 
754 	/*
755 	 * Re-scan is supposed to remove and add children, but if someone has
756 	 * deleted the hints for a child we attached earlier, we have no easy
757 	 * way to handle that.  So this just attaches new children for whom new
758 	 * hints or drivers have arrived since we last tried.
759 	 */
760 	bus_enumerate_hinted_children(dev);
761 	bus_attach_children(dev);
762 	return (0);
763 }
764 
765 static void
gpiobus_hinted_child(device_t bus,const char * dname,int dunit)766 gpiobus_hinted_child(device_t bus, const char *dname, int dunit)
767 {
768 	struct gpiobus_softc *sc = GPIOBUS_SOFTC(bus);
769 	device_t child;
770 	const char *pins;
771 	int irq, pinmask;
772 
773 	if (device_find_child(bus, dname, dunit) != NULL) {
774 		return;
775 	}
776 
777 	child = BUS_ADD_CHILD(bus, 0, dname, dunit);
778 	if (resource_int_value(dname, dunit, "pins", &pinmask) == 0) {
779 		if (gpiobus_parse_pins(sc, child, pinmask)) {
780 			device_delete_child(bus, child);
781 			return;
782 		}
783 	}
784 	else if (resource_string_value(dname, dunit, "pin_list", &pins) == 0) {
785 		if (gpiobus_parse_pin_list(sc, child, pins)) {
786 			device_delete_child(bus, child);
787 			return;
788 		}
789 	}
790 	if (resource_int_value(dname, dunit, "irq", &irq) == 0) {
791 		if (bus_set_resource(child, SYS_RES_IRQ, 0, irq, 1) != 0)
792 			device_printf(bus,
793 			    "warning: bus_set_resource() failed\n");
794 	}
795 }
796 
797 int
gpiobus_read_ivar(device_t dev,device_t child,int which,uintptr_t * result)798 gpiobus_read_ivar(device_t dev, device_t child, int which, uintptr_t *result)
799 {
800 	struct gpiobus_ivar *devi;
801 
802 	devi = GPIOBUS_IVAR(child);
803         switch (which) {
804 	case GPIOBUS_IVAR_NPINS:
805 		*result = devi->npins;
806 		break;
807 	case GPIOBUS_IVAR_PINS:
808 		/* Children do not ever need to directly examine this. */
809 		return (ENOTSUP);
810         default:
811                 return (ENOENT);
812         }
813 
814 	return (0);
815 }
816 
817 static int
gpiobus_write_ivar(device_t dev,device_t child,int which,uintptr_t value)818 gpiobus_write_ivar(device_t dev, device_t child, int which, uintptr_t value)
819 {
820 	struct gpiobus_ivar *devi;
821 	const uint32_t *ptr;
822 	int i;
823 
824 	devi = GPIOBUS_IVAR(child);
825         switch (which) {
826 	case GPIOBUS_IVAR_NPINS:
827 		/* GPIO ivars are set once. */
828 		if (devi->npins != 0) {
829 			return (EBUSY);
830 		}
831 		devi->npins = value;
832 		if (gpiobus_alloc_ivars(devi) != 0) {
833 			device_printf(child, "cannot allocate device ivars\n");
834 			devi->npins = 0;
835 			return (ENOMEM);
836 		}
837 		break;
838 	case GPIOBUS_IVAR_PINS:
839 		ptr = (const uint32_t *)value;
840 		for (i = 0; i < devi->npins; i++)
841 			devi->pins[i] = ptr[i];
842 		if (gpiobus_acquire_child_pins(dev, child) != 0)
843 			return (EBUSY);
844 		break;
845         default:
846                 return (ENOENT);
847         }
848 
849         return (0);
850 }
851 
852 static struct rman *
gpiobus_get_rman(device_t bus,int type,u_int flags)853 gpiobus_get_rman(device_t bus, int type, u_int flags)
854 {
855 	struct gpiobus_softc *sc;
856 
857 	sc = device_get_softc(bus);
858 	switch (type) {
859 	case SYS_RES_IRQ:
860 		return (&sc->sc_intr_rman);
861 	default:
862 		return (NULL);
863 	}
864 }
865 
866 static struct resource *
gpiobus_alloc_resource(device_t bus,device_t child,int type,int * rid,rman_res_t start,rman_res_t end,rman_res_t count,u_int flags)867 gpiobus_alloc_resource(device_t bus, device_t child, int type, int *rid,
868     rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
869 {
870 	struct resource_list *rl;
871 	struct resource_list_entry *rle;
872 	int isdefault;
873 
874 	isdefault = (RMAN_IS_DEFAULT_RANGE(start, end) && count == 1);
875 	if (isdefault) {
876 		rl = BUS_GET_RESOURCE_LIST(bus, child);
877 		if (rl == NULL)
878 			return (NULL);
879 		rle = resource_list_find(rl, type, *rid);
880 		if (rle == NULL)
881 			return (NULL);
882 		start = rle->start;
883 		count = rle->count;
884 		end = rle->end;
885 	}
886 	return (bus_generic_rman_alloc_resource(bus, child, type, rid, start,
887 	    end, count, flags));
888 }
889 
890 static int
gpiobus_release_resource(device_t dev,device_t child,struct resource * r)891 gpiobus_release_resource(device_t dev, device_t child, struct resource *r)
892 {
893 	int err;
894 #ifdef INTRNG
895 	u_int irq;
896 
897 	irq = rman_get_start(r);
898 	MPASS(irq == rman_get_end(r));
899 #endif
900 	err = bus_generic_rman_release_resource(dev, child, r);
901 	if (err != 0)
902 		return (err);
903 #ifdef INTRNG
904 	intr_unmap_irq(irq);
905 #endif
906 	return (0);
907 }
908 
909 static struct resource_list *
gpiobus_get_resource_list(device_t bus __unused,device_t child)910 gpiobus_get_resource_list(device_t bus __unused, device_t child)
911 {
912 	struct gpiobus_ivar *ivar;
913 
914 	ivar = GPIOBUS_IVAR(child);
915 
916 	return (&ivar->rl);
917 }
918 
919 static int
gpiobus_acquire_bus(device_t busdev,device_t child,int how)920 gpiobus_acquire_bus(device_t busdev, device_t child, int how)
921 {
922 	struct gpiobus_softc *sc;
923 
924 	sc = device_get_softc(busdev);
925 	GPIOBUS_ASSERT_UNLOCKED(sc);
926 	GPIOBUS_LOCK(sc);
927 	if (sc->sc_owner != NULL) {
928 		if (sc->sc_owner == child)
929 			panic("%s: %s still owns the bus.",
930 			    device_get_nameunit(busdev),
931 			    device_get_nameunit(child));
932 		if (how == GPIOBUS_DONTWAIT) {
933 			GPIOBUS_UNLOCK(sc);
934 			return (EWOULDBLOCK);
935 		}
936 		while (sc->sc_owner != NULL)
937 			mtx_sleep(sc, &sc->sc_mtx, 0, "gpiobuswait", 0);
938 	}
939 	sc->sc_owner = child;
940 	GPIOBUS_UNLOCK(sc);
941 
942 	return (0);
943 }
944 
945 static void
gpiobus_release_bus(device_t busdev,device_t child)946 gpiobus_release_bus(device_t busdev, device_t child)
947 {
948 	struct gpiobus_softc *sc;
949 
950 	sc = device_get_softc(busdev);
951 	GPIOBUS_ASSERT_UNLOCKED(sc);
952 	GPIOBUS_LOCK(sc);
953 	if (sc->sc_owner == NULL)
954 		panic("%s: %s releasing unowned bus.",
955 		    device_get_nameunit(busdev),
956 		    device_get_nameunit(child));
957 	if (sc->sc_owner != child)
958 		panic("%s: %s trying to release bus owned by %s",
959 		    device_get_nameunit(busdev),
960 		    device_get_nameunit(child),
961 		    device_get_nameunit(sc->sc_owner));
962 	sc->sc_owner = NULL;
963 	wakeup(sc);
964 	GPIOBUS_UNLOCK(sc);
965 }
966 
967 static int
gpiobus_pin_setflags(device_t dev,device_t child,uint32_t pin,uint32_t flags)968 gpiobus_pin_setflags(device_t dev, device_t child, uint32_t pin,
969     uint32_t flags)
970 {
971 	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
972 	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
973 	uint32_t caps;
974 
975 	if (pin >= devi->npins)
976 		return (EINVAL);
977 	if (GPIO_PIN_GETCAPS(sc->sc_dev, devi->pins[pin], &caps) != 0)
978 		return (EINVAL);
979 	if (gpio_check_flags(caps, flags) != 0)
980 		return (EINVAL);
981 
982 	return (GPIO_PIN_SETFLAGS(sc->sc_dev, devi->pins[pin], flags));
983 }
984 
985 static int
gpiobus_pin_getflags(device_t dev,device_t child,uint32_t pin,uint32_t * flags)986 gpiobus_pin_getflags(device_t dev, device_t child, uint32_t pin,
987     uint32_t *flags)
988 {
989 	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
990 	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
991 
992 	if (pin >= devi->npins)
993 		return (EINVAL);
994 
995 	return (GPIO_PIN_GETFLAGS(sc->sc_dev, devi->pins[pin], flags));
996 }
997 
998 static int
gpiobus_pin_getcaps(device_t dev,device_t child,uint32_t pin,uint32_t * caps)999 gpiobus_pin_getcaps(device_t dev, device_t child, uint32_t pin,
1000     uint32_t *caps)
1001 {
1002 	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
1003 	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
1004 
1005 	if (pin >= devi->npins)
1006 		return (EINVAL);
1007 
1008 	return (GPIO_PIN_GETCAPS(sc->sc_dev, devi->pins[pin], caps));
1009 }
1010 
1011 static int
gpiobus_pin_set(device_t dev,device_t child,uint32_t pin,unsigned int value)1012 gpiobus_pin_set(device_t dev, device_t child, uint32_t pin,
1013     unsigned int value)
1014 {
1015 	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
1016 	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
1017 
1018 	if (pin >= devi->npins)
1019 		return (EINVAL);
1020 
1021 	return (GPIO_PIN_SET(sc->sc_dev, devi->pins[pin], value));
1022 }
1023 
1024 static int
gpiobus_pin_get(device_t dev,device_t child,uint32_t pin,unsigned int * value)1025 gpiobus_pin_get(device_t dev, device_t child, uint32_t pin,
1026     unsigned int *value)
1027 {
1028 	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
1029 	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
1030 
1031 	if (pin >= devi->npins)
1032 		return (EINVAL);
1033 
1034 	return (GPIO_PIN_GET(sc->sc_dev, devi->pins[pin], value));
1035 }
1036 
1037 static int
gpiobus_pin_toggle(device_t dev,device_t child,uint32_t pin)1038 gpiobus_pin_toggle(device_t dev, device_t child, uint32_t pin)
1039 {
1040 	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
1041 	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
1042 
1043 	if (pin >= devi->npins)
1044 		return (EINVAL);
1045 
1046 	return (GPIO_PIN_TOGGLE(sc->sc_dev, devi->pins[pin]));
1047 }
1048 
1049 /*
1050  * Verify that a child has all the pins they are requesting
1051  * to access in their ivars.
1052  */
1053 static bool
gpiobus_pin_verify_32(struct gpiobus_ivar * devi,uint32_t first_pin,uint32_t num_pins)1054 gpiobus_pin_verify_32(struct gpiobus_ivar *devi, uint32_t first_pin,
1055     uint32_t num_pins)
1056 {
1057 	if (first_pin + num_pins > devi->npins)
1058 		return (false);
1059 
1060 	/* Make sure the pins are consecutive. */
1061 	for (uint32_t pin = first_pin; pin < first_pin + num_pins - 1; pin++) {
1062 		if (devi->pins[pin] + 1 != devi->pins[pin + 1])
1063 			return (false);
1064 	}
1065 
1066 	return (true);
1067 }
1068 
1069 static int
gpiobus_pin_access_32(device_t dev,device_t child,uint32_t first_pin,uint32_t clear_pins,uint32_t change_pins,uint32_t * orig_pins)1070 gpiobus_pin_access_32(device_t dev, device_t child, uint32_t first_pin,
1071     uint32_t clear_pins, uint32_t change_pins, uint32_t *orig_pins)
1072 {
1073 	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
1074 	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
1075 
1076 	if (!gpiobus_pin_verify_32(devi, first_pin, 32))
1077 		return (EINVAL);
1078 
1079 	return (GPIO_PIN_ACCESS_32(sc->sc_dev, devi->pins[first_pin],
1080 	    clear_pins, change_pins, orig_pins));
1081 }
1082 
1083 static int
gpiobus_pin_config_32(device_t dev,device_t child,uint32_t first_pin,uint32_t num_pins,uint32_t * pin_flags)1084 gpiobus_pin_config_32(device_t dev, device_t child, uint32_t first_pin,
1085     uint32_t num_pins, uint32_t *pin_flags)
1086 {
1087 	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
1088 	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
1089 
1090 	if (num_pins > 32)
1091 		return (EINVAL);
1092 	if (!gpiobus_pin_verify_32(devi, first_pin, num_pins))
1093 		return (EINVAL);
1094 
1095 	return (GPIO_PIN_CONFIG_32(sc->sc_dev,
1096 	    devi->pins[first_pin], num_pins, pin_flags));
1097 }
1098 
1099 static int
gpiobus_pin_getname(device_t dev,uint32_t pin,char * name)1100 gpiobus_pin_getname(device_t dev, uint32_t pin, char *name)
1101 {
1102 	struct gpiobus_softc *sc;
1103 
1104 	sc = GPIOBUS_SOFTC(dev);
1105 	if (pin > sc->sc_npins)
1106 		return (EINVAL);
1107 	/* Did we have a name for this pin ? */
1108 	if (sc->sc_pins[pin].name != NULL) {
1109 		memcpy(name, sc->sc_pins[pin].name, GPIOMAXNAME);
1110 		return (0);
1111 	}
1112 
1113 	/* Return the default pin name. */
1114 	return (GPIO_PIN_GETNAME(device_get_parent(dev), pin, name));
1115 }
1116 
1117 static int
gpiobus_pin_setname(device_t dev,uint32_t pin,const char * name)1118 gpiobus_pin_setname(device_t dev, uint32_t pin, const char *name)
1119 {
1120 	struct gpiobus_softc *sc;
1121 
1122 	sc = GPIOBUS_SOFTC(dev);
1123 	if (pin > sc->sc_npins)
1124 		return (EINVAL);
1125 	if (name == NULL)
1126 		return (EINVAL);
1127 	/* Save the pin name. */
1128 	if (sc->sc_pins[pin].name == NULL)
1129 		sc->sc_pins[pin].name = malloc(GPIOMAXNAME, M_DEVBUF,
1130 		    M_WAITOK | M_ZERO);
1131 	strlcpy(sc->sc_pins[pin].name, name, GPIOMAXNAME);
1132 
1133 	return (0);
1134 }
1135 
1136 static device_method_t gpiobus_methods[] = {
1137 	/* Device interface */
1138 	DEVMETHOD(device_probe,		gpiobus_probe),
1139 	DEVMETHOD(device_attach,	gpiobus_attach),
1140 	DEVMETHOD(device_detach,	gpiobus_detach),
1141 	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
1142 	DEVMETHOD(device_suspend,	gpiobus_suspend),
1143 	DEVMETHOD(device_resume,	gpiobus_resume),
1144 
1145 	/* Bus interface */
1146 	DEVMETHOD(bus_setup_intr,	bus_generic_setup_intr),
1147 	DEVMETHOD(bus_config_intr,	bus_generic_config_intr),
1148 	DEVMETHOD(bus_teardown_intr,	bus_generic_teardown_intr),
1149 	DEVMETHOD(bus_delete_resource,	bus_generic_rl_delete_resource),
1150 	DEVMETHOD(bus_get_resource,	bus_generic_rl_get_resource),
1151 	DEVMETHOD(bus_set_resource,	bus_generic_rl_set_resource),
1152 	DEVMETHOD(bus_alloc_resource,	gpiobus_alloc_resource),
1153 	DEVMETHOD(bus_release_resource,	gpiobus_release_resource),
1154 	DEVMETHOD(bus_activate_resource,	bus_generic_rman_activate_resource),
1155 	DEVMETHOD(bus_deactivate_resource,	bus_generic_rman_deactivate_resource),
1156 	DEVMETHOD(bus_get_resource_list,	gpiobus_get_resource_list),
1157 	DEVMETHOD(bus_get_rman,		gpiobus_get_rman),
1158 	DEVMETHOD(bus_add_child,	gpiobus_add_child),
1159 	DEVMETHOD(bus_child_deleted,	gpiobus_child_deleted),
1160 	DEVMETHOD(bus_rescan,		gpiobus_rescan),
1161 	DEVMETHOD(bus_probe_nomatch,	gpiobus_probe_nomatch),
1162 	DEVMETHOD(bus_print_child,	gpiobus_print_child),
1163 	DEVMETHOD(bus_child_location,	gpiobus_child_location),
1164 	DEVMETHOD(bus_hinted_child,	gpiobus_hinted_child),
1165 	DEVMETHOD(bus_read_ivar,        gpiobus_read_ivar),
1166 	DEVMETHOD(bus_write_ivar,       gpiobus_write_ivar),
1167 
1168 	/* GPIO protocol */
1169 	DEVMETHOD(gpiobus_acquire_bus,	gpiobus_acquire_bus),
1170 	DEVMETHOD(gpiobus_release_bus,	gpiobus_release_bus),
1171 	DEVMETHOD(gpiobus_pin_getflags,	gpiobus_pin_getflags),
1172 	DEVMETHOD(gpiobus_pin_getcaps,	gpiobus_pin_getcaps),
1173 	DEVMETHOD(gpiobus_pin_setflags,	gpiobus_pin_setflags),
1174 	DEVMETHOD(gpiobus_pin_get,	gpiobus_pin_get),
1175 	DEVMETHOD(gpiobus_pin_set,	gpiobus_pin_set),
1176 	DEVMETHOD(gpiobus_pin_toggle,	gpiobus_pin_toggle),
1177 	DEVMETHOD(gpiobus_pin_access_32,gpiobus_pin_access_32),
1178 	DEVMETHOD(gpiobus_pin_config_32,gpiobus_pin_config_32),
1179 	DEVMETHOD(gpiobus_pin_getname,	gpiobus_pin_getname),
1180 	DEVMETHOD(gpiobus_pin_setname,	gpiobus_pin_setname),
1181 
1182 	DEVMETHOD_END
1183 };
1184 
1185 driver_t gpiobus_driver = {
1186 	"gpiobus",
1187 	gpiobus_methods,
1188 	sizeof(struct gpiobus_softc)
1189 };
1190 
1191 EARLY_DRIVER_MODULE(gpiobus, gpio, gpiobus_driver, 0, 0,
1192     BUS_PASS_BUS + BUS_PASS_ORDER_MIDDLE);
1193 MODULE_VERSION(gpiobus, 1);
1194