xref: /freebsd/sys/dev/gpio/gpiobus.c (revision 9c2509f831e8194ef8c30aa5d839a7eb2197ff7f)
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 *
gpio_alloc_intr_resource(device_t consumer_dev,int * rid,u_int alloc_flags,gpio_pin_t pin,uint32_t intr_mode)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_free_intr_map_data((struct intr_map_data *)gpio_data);
114 		return (NULL);
115 	}
116 	rman_set_virtual(res, gpio_data);
117 	return (res);
118 }
119 #else
120 struct resource *
gpio_alloc_intr_resource(device_t consumer_dev,int * rid,u_int alloc_flags,gpio_pin_t pin,uint32_t intr_mode)121 gpio_alloc_intr_resource(device_t consumer_dev, int *rid, u_int alloc_flags,
122     gpio_pin_t pin, uint32_t intr_mode)
123 {
124 
125 	return (NULL);
126 }
127 #endif
128 
129 int
gpio_check_flags(uint32_t caps,uint32_t flags)130 gpio_check_flags(uint32_t caps, uint32_t flags)
131 {
132 
133 	/* Filter unwanted flags. */
134 	flags &= caps;
135 
136 	/* Cannot mix input/output together. */
137 	if (flags & GPIO_PIN_INPUT && flags & GPIO_PIN_OUTPUT)
138 		return (EINVAL);
139 	/* Cannot mix pull-up/pull-down together. */
140 	if (flags & GPIO_PIN_PULLUP && flags & GPIO_PIN_PULLDOWN)
141 		return (EINVAL);
142 	/* Cannot mix output and interrupt flags together */
143 	if (flags & GPIO_PIN_OUTPUT && flags & GPIO_INTR_MASK)
144 		return (EINVAL);
145 	/* Only one interrupt flag can be defined at once */
146 	if ((flags & GPIO_INTR_MASK) & ((flags & GPIO_INTR_MASK) - 1))
147 		return (EINVAL);
148 	/* The interrupt attached flag cannot be set */
149 	if (flags & GPIO_INTR_ATTACHED)
150 		return (EINVAL);
151 
152 	return (0);
153 }
154 
155 int
gpio_pin_get_by_bus_pinnum(device_t busdev,uint32_t pinnum,gpio_pin_t * ppin)156 gpio_pin_get_by_bus_pinnum(device_t busdev, uint32_t pinnum, gpio_pin_t *ppin)
157 {
158 	gpio_pin_t pin;
159 	int err;
160 
161 	err = gpiobus_acquire_pin(busdev, pinnum);
162 	if (err != 0)
163 		return (EBUSY);
164 
165 	pin = malloc(sizeof(*pin), M_DEVBUF, M_WAITOK | M_ZERO);
166 
167 	pin->dev = device_get_parent(busdev);
168 	pin->pin = pinnum;
169 	pin->flags = 0;
170 
171 	*ppin = pin;
172 	return (0);
173 }
174 
175 int
gpio_pin_get_by_child_index(device_t childdev,uint32_t idx,gpio_pin_t * ppin)176 gpio_pin_get_by_child_index(device_t childdev, uint32_t idx, gpio_pin_t *ppin)
177 {
178 	struct gpiobus_ivar *devi;
179 
180 	devi = GPIOBUS_IVAR(childdev);
181 	if (idx >= devi->npins)
182 		return (EINVAL);
183 
184 	return (gpio_pin_get_by_bus_pinnum(device_get_parent(childdev),
185 	    devi->pins[idx], ppin));
186 }
187 
188 int
gpio_pin_getcaps(gpio_pin_t pin,uint32_t * caps)189 gpio_pin_getcaps(gpio_pin_t pin, uint32_t *caps)
190 {
191 
192 	KASSERT(pin != NULL, ("GPIO pin is NULL."));
193 	KASSERT(pin->dev != NULL, ("GPIO pin device is NULL."));
194 	return (GPIO_PIN_GETCAPS(pin->dev, pin->pin, caps));
195 }
196 
197 int
gpio_pin_is_active(gpio_pin_t pin,bool * active)198 gpio_pin_is_active(gpio_pin_t pin, bool *active)
199 {
200 	int rv;
201 	uint32_t tmp;
202 
203 	KASSERT(pin != NULL, ("GPIO pin is NULL."));
204 	KASSERT(pin->dev != NULL, ("GPIO pin device is NULL."));
205 	rv = GPIO_PIN_GET(pin->dev, pin->pin, &tmp);
206 	if (rv  != 0) {
207 		return (rv);
208 	}
209 
210 	if (pin->flags & GPIO_ACTIVE_LOW)
211 		*active = tmp == 0;
212 	else
213 		*active = tmp != 0;
214 	return (0);
215 }
216 
217 /*
218  * Note that this function should only
219  * be used in cases where a pre-existing
220  * gpiobus_pin structure exists. In most
221  * cases, the gpio_pin_get_by_* functions
222  * suffice.
223  */
224 int
gpio_pin_acquire(gpio_pin_t gpio)225 gpio_pin_acquire(gpio_pin_t gpio)
226 {
227 	device_t busdev;
228 
229 	KASSERT(gpio != NULL, ("GPIO pin is NULL."));
230 	KASSERT(gpio->dev != NULL, ("GPIO pin device is NULL."));
231 
232 	busdev = GPIO_GET_BUS(gpio->dev);
233 	if (busdev == NULL)
234 		return (ENXIO);
235 
236 	return (gpiobus_acquire_pin(busdev, gpio->pin));
237 }
238 
239 void
gpio_pin_release(gpio_pin_t gpio)240 gpio_pin_release(gpio_pin_t gpio)
241 {
242 	device_t busdev;
243 
244 	KASSERT(gpio != NULL, ("GPIO pin is NULL."));
245 	KASSERT(gpio->dev != NULL, ("GPIO pin device is NULL."));
246 
247 	busdev = GPIO_GET_BUS(gpio->dev);
248 	KASSERT(busdev != NULL, ("gpiobus dev is NULL."));
249 
250 	gpiobus_release_pin(busdev, gpio->pin);
251 	free(gpio, M_DEVBUF);
252 }
253 
254 int
gpio_pin_set_active(gpio_pin_t pin,bool active)255 gpio_pin_set_active(gpio_pin_t pin, bool active)
256 {
257 	int rv;
258 	uint32_t tmp;
259 
260 	if (pin->flags & GPIO_ACTIVE_LOW)
261 		tmp = active ? 0 : 1;
262 	else
263 		tmp = active ? 1 : 0;
264 
265 	KASSERT(pin != NULL, ("GPIO pin is NULL."));
266 	KASSERT(pin->dev != NULL, ("GPIO pin device is NULL."));
267 	rv = GPIO_PIN_SET(pin->dev, pin->pin, tmp);
268 	return (rv);
269 }
270 
271 int
gpio_pin_setflags(gpio_pin_t pin,uint32_t flags)272 gpio_pin_setflags(gpio_pin_t pin, uint32_t flags)
273 {
274 	int rv;
275 
276 	KASSERT(pin != NULL, ("GPIO pin is NULL."));
277 	KASSERT(pin->dev != NULL, ("GPIO pin device is NULL."));
278 
279 	rv = GPIO_PIN_SETFLAGS(pin->dev, pin->pin, flags);
280 	return (rv);
281 }
282 
283 static void
gpiobus_print_pins(struct gpiobus_ivar * devi,struct sbuf * sb)284 gpiobus_print_pins(struct gpiobus_ivar *devi, struct sbuf *sb)
285 {
286 	int i, range_start, range_stop, need_coma;
287 
288 	if (devi->npins == 0)
289 		return;
290 
291 	need_coma = 0;
292 	range_start = range_stop = devi->pins[0];
293 	for (i = 1; i < devi->npins; i++) {
294 		if (devi->pins[i] != (range_stop + 1)) {
295 			if (need_coma)
296 				sbuf_cat(sb, ",");
297 			if (range_start != range_stop)
298 				sbuf_printf(sb, "%d-%d", range_start, range_stop);
299 			else
300 				sbuf_printf(sb, "%d", range_start);
301 			range_start = range_stop = devi->pins[i];
302 			need_coma = 1;
303 		}
304 		else
305 			range_stop++;
306 	}
307 
308 	if (need_coma)
309 		sbuf_cat(sb, ",");
310 	if (range_start != range_stop)
311 		sbuf_printf(sb, "%d-%d", range_start, range_stop);
312 	else
313 		sbuf_printf(sb, "%d", range_start);
314 }
315 
316 device_t
gpiobus_add_bus(device_t dev)317 gpiobus_add_bus(device_t dev)
318 {
319 	device_t busdev;
320 
321 	busdev = device_add_child(dev, "gpiobus", DEVICE_UNIT_ANY);
322 	if (busdev == NULL)
323 		return (NULL);
324 	if (device_add_child(dev, "gpioc", DEVICE_UNIT_ANY) == NULL) {
325 		device_delete_child(dev, busdev);
326 		return (NULL);
327 	}
328 #ifdef FDT
329 	ofw_gpiobus_register_provider(dev);
330 #endif
331 	return (busdev);
332 }
333 
334 /*
335  * Attach a gpiobus child.
336  * Note that the controller is expected
337  * to be fully initialized at this point.
338  */
339 device_t
gpiobus_attach_bus(device_t dev)340 gpiobus_attach_bus(device_t dev)
341 {
342 	device_t busdev;
343 
344 	busdev = gpiobus_add_bus(dev);
345 	if (busdev == NULL)
346 		return (NULL);
347 
348 	bus_attach_children(dev);
349 	return (busdev);
350 }
351 
352 int
gpiobus_detach_bus(device_t dev)353 gpiobus_detach_bus(device_t dev)
354 {
355 #ifdef FDT
356 	ofw_gpiobus_unregister_provider(dev);
357 #endif
358 	return (bus_generic_detach(dev));
359 }
360 
361 int
gpiobus_init_softc(device_t dev)362 gpiobus_init_softc(device_t dev)
363 {
364 	struct gpiobus_softc *sc;
365 
366 	sc = GPIOBUS_SOFTC(dev);
367 	sc->sc_busdev = dev;
368 	sc->sc_dev = device_get_parent(dev);
369 	sc->sc_intr_rman.rm_type = RMAN_ARRAY;
370 	sc->sc_intr_rman.rm_descr = "GPIO Interrupts";
371 	if (rman_init(&sc->sc_intr_rman) != 0 ||
372 	    rman_manage_region(&sc->sc_intr_rman, 0, ~0) != 0)
373 		panic("%s: failed to set up rman.", __func__);
374 
375 	if (GPIO_PIN_MAX(sc->sc_dev, &sc->sc_npins) != 0)
376 		return (ENXIO);
377 
378 	KASSERT(sc->sc_npins >= 0, ("GPIO device with no pins"));
379 
380 	/* Pins = GPIO_PIN_MAX() + 1 */
381 	sc->sc_npins++;
382 
383 	sc->sc_pins = malloc(sizeof(*sc->sc_pins) * sc->sc_npins, M_DEVBUF,
384 	    M_NOWAIT | M_ZERO);
385 	if (sc->sc_pins == NULL)
386 		return (ENOMEM);
387 
388 	/* Initialize the bus lock. */
389 	GPIOBUS_LOCK_INIT(sc);
390 
391 	return (0);
392 }
393 
394 int
gpiobus_alloc_ivars(struct gpiobus_ivar * devi)395 gpiobus_alloc_ivars(struct gpiobus_ivar *devi)
396 {
397 
398 	/* Allocate pins and flags memory. */
399 	devi->pins = malloc(sizeof(uint32_t) * devi->npins, M_DEVBUF,
400 	    M_NOWAIT | M_ZERO);
401 	if (devi->pins == NULL)
402 		return (ENOMEM);
403 	return (0);
404 }
405 
406 void
gpiobus_free_ivars(struct gpiobus_ivar * devi)407 gpiobus_free_ivars(struct gpiobus_ivar *devi)
408 {
409 
410 	if (devi->pins) {
411 		free(devi->pins, M_DEVBUF);
412 		devi->pins = NULL;
413 	}
414 	devi->npins = 0;
415 }
416 
417 int
gpiobus_acquire_pin(device_t bus,uint32_t pin)418 gpiobus_acquire_pin(device_t bus, uint32_t pin)
419 {
420 	struct gpiobus_softc *sc;
421 
422 	sc = device_get_softc(bus);
423 	/* Consistency check. */
424 	if (pin >= sc->sc_npins) {
425 		panic("%s: invalid pin %d, max: %d",
426 		    device_get_nameunit(bus), pin, sc->sc_npins - 1);
427 	}
428 	/* Mark pin as mapped and give warning if it's already mapped. */
429 	if (sc->sc_pins[pin].mapped) {
430 		device_printf(bus, "warning: pin %d is already mapped\n", pin);
431 		return (EBUSY);
432 	}
433 	sc->sc_pins[pin].mapped = 1;
434 
435 	return (0);
436 }
437 
438 /* Release mapped pin */
439 void
gpiobus_release_pin(device_t bus,uint32_t pin)440 gpiobus_release_pin(device_t bus, uint32_t pin)
441 {
442 	struct gpiobus_softc *sc;
443 
444 	sc = device_get_softc(bus);
445 	/* Consistency check. */
446 	if (pin >= sc->sc_npins) {
447 		panic("%s: invalid pin %d, max: %d",
448 		    device_get_nameunit(bus), pin, sc->sc_npins - 1);
449 	}
450 
451 	if (!sc->sc_pins[pin].mapped)
452 		panic("%s: pin %d is not mapped", device_get_nameunit(bus),
453 		    pin);
454 
455 	sc->sc_pins[pin].mapped = 0;
456 }
457 
458 static int
gpiobus_acquire_child_pins(device_t dev,device_t child)459 gpiobus_acquire_child_pins(device_t dev, device_t child)
460 {
461 	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
462 	int i;
463 
464 	for (i = 0; i < devi->npins; i++) {
465 		/* Reserve the GPIO pin. */
466 		if (gpiobus_acquire_pin(dev, devi->pins[i]) != 0) {
467 			device_printf(child, "cannot acquire pin %d\n",
468 			    devi->pins[i]);
469 			while (--i >= 0) {
470 				gpiobus_release_pin(dev, devi->pins[i]);
471 			}
472 			gpiobus_free_ivars(devi);
473 			return (EBUSY);
474 		}
475 	}
476 	for (i = 0; i < devi->npins; i++) {
477 		/* Use the child name as pin name. */
478 		GPIOBUS_PIN_SETNAME(dev, devi->pins[i],
479 		    device_get_nameunit(child));
480 
481 	}
482 	return (0);
483 }
484 
485 static int
gpiobus_parse_pins(struct gpiobus_softc * sc,device_t child,int mask)486 gpiobus_parse_pins(struct gpiobus_softc *sc, device_t child, int mask)
487 {
488 	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
489 	int i, npins;
490 
491 	npins = 0;
492 	for (i = 0; i < 32; i++) {
493 		if (mask & (1 << i))
494 			npins++;
495 	}
496 	if (npins == 0) {
497 		device_printf(child, "empty pin mask\n");
498 		return (EINVAL);
499 	}
500 	devi->npins = npins;
501 	if (gpiobus_alloc_ivars(devi) != 0) {
502 		device_printf(child, "cannot allocate device ivars\n");
503 		return (EINVAL);
504 	}
505 	npins = 0;
506 	for (i = 0; i < 32; i++) {
507 		if ((mask & (1 << i)) == 0)
508 			continue;
509 		devi->pins[npins++] = i;
510 	}
511 
512 	return (0);
513 }
514 
515 static int
gpiobus_parse_pin_list(struct gpiobus_softc * sc,device_t child,const char * pins)516 gpiobus_parse_pin_list(struct gpiobus_softc *sc, device_t child,
517     const char *pins)
518 {
519 	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
520 	const char *p;
521 	char *endp;
522 	unsigned long pin;
523 	int i, npins;
524 
525 	npins = 0;
526 	p = pins;
527 	for (;;) {
528 		pin = strtoul(p, &endp, 0);
529 		if (endp == p)
530 			break;
531 		npins++;
532 		if (*endp == '\0')
533 			break;
534 		p = endp + 1;
535 	}
536 
537 	if (*endp != '\0') {
538 		device_printf(child, "garbage in the pin list: %s\n", endp);
539 		return (EINVAL);
540 	}
541 	if (npins == 0) {
542 		device_printf(child, "empty pin list\n");
543 		return (EINVAL);
544 	}
545 
546 	devi->npins = npins;
547 	if (gpiobus_alloc_ivars(devi) != 0) {
548 		device_printf(child, "cannot allocate device ivars\n");
549 		return (EINVAL);
550 	}
551 
552 	i = 0;
553 	p = pins;
554 	for (;;) {
555 		pin = strtoul(p, &endp, 0);
556 
557 		devi->pins[i] = pin;
558 
559 		if (*endp == '\0')
560 			break;
561 		i++;
562 		p = endp + 1;
563 	}
564 
565 	return (0);
566 }
567 
568 static int
gpiobus_probe(device_t dev)569 gpiobus_probe(device_t dev)
570 {
571 	device_set_desc(dev, "GPIO bus");
572 
573 	return (BUS_PROBE_GENERIC);
574 }
575 
576 int
gpiobus_attach(device_t dev)577 gpiobus_attach(device_t dev)
578 {
579 	int err;
580 
581 	err = gpiobus_init_softc(dev);
582 	if (err != 0)
583 		return (err);
584 
585 	/*
586 	 * Get parent's pins and mark them as unmapped
587 	 */
588 	bus_identify_children(dev);
589 	bus_enumerate_hinted_children(dev);
590 
591 	bus_attach_children(dev);
592 	return (0);
593 }
594 
595 /*
596  * Since this is not a self-enumerating bus, and since we always add
597  * children in attach, we have to always delete children here.
598  */
599 int
gpiobus_detach(device_t dev)600 gpiobus_detach(device_t dev)
601 {
602 	struct gpiobus_softc *sc;
603 	int i, err;
604 
605 	sc = GPIOBUS_SOFTC(dev);
606 	KASSERT(mtx_initialized(&sc->sc_mtx),
607 	    ("gpiobus mutex not initialized"));
608 	GPIOBUS_LOCK_DESTROY(sc);
609 
610 	if ((err = bus_detach_children(dev)) != 0)
611 		return (err);
612 
613 	rman_fini(&sc->sc_intr_rman);
614 	if (sc->sc_pins) {
615 		for (i = 0; i < sc->sc_npins; i++) {
616 			if (sc->sc_pins[i].name != NULL)
617 				free(sc->sc_pins[i].name, M_DEVBUF);
618 			sc->sc_pins[i].name = NULL;
619 		}
620 		free(sc->sc_pins, M_DEVBUF);
621 		sc->sc_pins = NULL;
622 	}
623 
624 	return (0);
625 }
626 
627 static int
gpiobus_suspend(device_t dev)628 gpiobus_suspend(device_t dev)
629 {
630 
631 	return (bus_generic_suspend(dev));
632 }
633 
634 static int
gpiobus_resume(device_t dev)635 gpiobus_resume(device_t dev)
636 {
637 
638 	return (bus_generic_resume(dev));
639 }
640 
641 static void
gpiobus_probe_nomatch(device_t dev,device_t child)642 gpiobus_probe_nomatch(device_t dev, device_t child)
643 {
644 	char pins[128];
645 	struct sbuf sb;
646 	struct gpiobus_ivar *devi;
647 
648 	devi = GPIOBUS_IVAR(child);
649 	sbuf_new(&sb, pins, sizeof(pins), SBUF_FIXEDLEN);
650 	gpiobus_print_pins(devi, &sb);
651 	sbuf_finish(&sb);
652 	device_printf(dev, "<unknown device> at pin%s %s",
653 	    devi->npins > 1 ? "s" : "", sbuf_data(&sb));
654 	resource_list_print_type(&devi->rl, "irq", SYS_RES_IRQ, "%jd");
655 	printf("\n");
656 }
657 
658 static int
gpiobus_print_child(device_t dev,device_t child)659 gpiobus_print_child(device_t dev, device_t child)
660 {
661 	char pins[128];
662 	struct sbuf sb;
663 	int retval = 0;
664 	struct gpiobus_ivar *devi;
665 
666 	devi = GPIOBUS_IVAR(child);
667 	retval += bus_print_child_header(dev, child);
668 	if (devi->npins > 0) {
669 		if (devi->npins > 1)
670 			retval += printf(" at pins ");
671 		else
672 			retval += printf(" at pin ");
673 		sbuf_new(&sb, pins, sizeof(pins), SBUF_FIXEDLEN);
674 		gpiobus_print_pins(devi, &sb);
675 		sbuf_finish(&sb);
676 		retval += printf("%s", sbuf_data(&sb));
677 	}
678 	resource_list_print_type(&devi->rl, "irq", SYS_RES_IRQ, "%jd");
679 	retval += bus_print_child_footer(dev, child);
680 
681 	return (retval);
682 }
683 
684 static int
gpiobus_child_location(device_t bus,device_t child,struct sbuf * sb)685 gpiobus_child_location(device_t bus, device_t child, struct sbuf *sb)
686 {
687 	struct gpiobus_ivar *devi;
688 
689 	devi = GPIOBUS_IVAR(child);
690 	sbuf_printf(sb, "pins=");
691 	gpiobus_print_pins(devi, sb);
692 
693 	return (0);
694 }
695 
696 static device_t
gpiobus_add_child(device_t dev,u_int order,const char * name,int unit)697 gpiobus_add_child(device_t dev, u_int order, const char *name, int unit)
698 {
699 	device_t child;
700 	struct gpiobus_ivar *devi;
701 
702 	child = device_add_child_ordered(dev, order, name, unit);
703 	if (child == NULL)
704 		return (child);
705 	devi = malloc(sizeof(struct gpiobus_ivar), M_DEVBUF, M_NOWAIT | M_ZERO);
706 	if (devi == NULL) {
707 		device_delete_child(dev, child);
708 		return (NULL);
709 	}
710 	resource_list_init(&devi->rl);
711 	device_set_ivars(child, devi);
712 
713 	return (child);
714 }
715 
716 static void
gpiobus_child_deleted(device_t dev,device_t child)717 gpiobus_child_deleted(device_t dev, device_t child)
718 {
719 	struct gpiobus_ivar *devi;
720 
721 	devi = GPIOBUS_IVAR(child);
722 	if (devi == NULL)
723 		return;
724 	gpiobus_free_ivars(devi);
725 	resource_list_free(&devi->rl);
726 	free(devi, M_DEVBUF);
727 }
728 
729 static int
gpiobus_rescan(device_t dev)730 gpiobus_rescan(device_t dev)
731 {
732 
733 	/*
734 	 * Re-scan is supposed to remove and add children, but if someone has
735 	 * deleted the hints for a child we attached earlier, we have no easy
736 	 * way to handle that.  So this just attaches new children for whom new
737 	 * hints or drivers have arrived since we last tried.
738 	 */
739 	bus_enumerate_hinted_children(dev);
740 	bus_attach_children(dev);
741 	return (0);
742 }
743 
744 static void
gpiobus_hinted_child(device_t bus,const char * dname,int dunit)745 gpiobus_hinted_child(device_t bus, const char *dname, int dunit)
746 {
747 	struct gpiobus_softc *sc = GPIOBUS_SOFTC(bus);
748 	device_t child;
749 	const char *pins;
750 	int irq, pinmask;
751 
752 	if (device_find_child(bus, dname, dunit) != NULL) {
753 		return;
754 	}
755 
756 	child = BUS_ADD_CHILD(bus, 0, dname, dunit);
757 	if (resource_int_value(dname, dunit, "pins", &pinmask) == 0) {
758 		if (gpiobus_parse_pins(sc, child, pinmask)) {
759 			device_delete_child(bus, child);
760 			return;
761 		}
762 	}
763 	else if (resource_string_value(dname, dunit, "pin_list", &pins) == 0) {
764 		if (gpiobus_parse_pin_list(sc, child, pins)) {
765 			device_delete_child(bus, child);
766 			return;
767 		}
768 	}
769 	if (resource_int_value(dname, dunit, "irq", &irq) == 0) {
770 		if (bus_set_resource(child, SYS_RES_IRQ, 0, irq, 1) != 0)
771 			device_printf(bus,
772 			    "warning: bus_set_resource() failed\n");
773 	}
774 }
775 
776 int
gpiobus_read_ivar(device_t dev,device_t child,int which,uintptr_t * result)777 gpiobus_read_ivar(device_t dev, device_t child, int which, uintptr_t *result)
778 {
779 	struct gpiobus_ivar *devi;
780 
781 	devi = GPIOBUS_IVAR(child);
782         switch (which) {
783 	case GPIOBUS_IVAR_NPINS:
784 		*result = devi->npins;
785 		break;
786 	case GPIOBUS_IVAR_PINS:
787 		/* Children do not ever need to directly examine this. */
788 		return (ENOTSUP);
789         default:
790                 return (ENOENT);
791         }
792 
793 	return (0);
794 }
795 
796 static int
gpiobus_write_ivar(device_t dev,device_t child,int which,uintptr_t value)797 gpiobus_write_ivar(device_t dev, device_t child, int which, uintptr_t value)
798 {
799 	struct gpiobus_ivar *devi;
800 	const uint32_t *ptr;
801 	int i;
802 
803 	devi = GPIOBUS_IVAR(child);
804         switch (which) {
805 	case GPIOBUS_IVAR_NPINS:
806 		/* GPIO ivars are set once. */
807 		if (devi->npins != 0) {
808 			return (EBUSY);
809 		}
810 		devi->npins = value;
811 		if (gpiobus_alloc_ivars(devi) != 0) {
812 			device_printf(child, "cannot allocate device ivars\n");
813 			devi->npins = 0;
814 			return (ENOMEM);
815 		}
816 		break;
817 	case GPIOBUS_IVAR_PINS:
818 		ptr = (const uint32_t *)value;
819 		for (i = 0; i < devi->npins; i++)
820 			devi->pins[i] = ptr[i];
821 		if (gpiobus_acquire_child_pins(dev, child) != 0)
822 			return (EBUSY);
823 		break;
824         default:
825                 return (ENOENT);
826         }
827 
828         return (0);
829 }
830 
831 static struct rman *
gpiobus_get_rman(device_t bus,int type,u_int flags)832 gpiobus_get_rman(device_t bus, int type, u_int flags)
833 {
834 	struct gpiobus_softc *sc;
835 
836 	sc = device_get_softc(bus);
837 	switch (type) {
838 	case SYS_RES_IRQ:
839 		return (&sc->sc_intr_rman);
840 	default:
841 		return (NULL);
842 	}
843 }
844 
845 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)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 resource_list *rl;
850 	struct resource_list_entry *rle;
851 	int isdefault;
852 
853 	isdefault = (RMAN_IS_DEFAULT_RANGE(start, end) && count == 1);
854 	if (isdefault) {
855 		rl = BUS_GET_RESOURCE_LIST(bus, child);
856 		if (rl == NULL)
857 			return (NULL);
858 		rle = resource_list_find(rl, type, *rid);
859 		if (rle == NULL)
860 			return (NULL);
861 		start = rle->start;
862 		count = rle->count;
863 		end = rle->end;
864 	}
865 	return (bus_generic_rman_alloc_resource(bus, child, type, rid, start,
866 	    end, count, flags));
867 }
868 
869 static struct resource_list *
gpiobus_get_resource_list(device_t bus __unused,device_t child)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
gpiobus_acquire_bus(device_t busdev,device_t child,int how)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
gpiobus_release_bus(device_t busdev,device_t child)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
gpiobus_pin_setflags(device_t dev,device_t child,uint32_t pin,uint32_t flags)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
gpiobus_pin_getflags(device_t dev,device_t child,uint32_t pin,uint32_t * flags)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
gpiobus_pin_getcaps(device_t dev,device_t child,uint32_t pin,uint32_t * caps)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
gpiobus_pin_set(device_t dev,device_t child,uint32_t pin,unsigned int value)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
gpiobus_pin_get(device_t dev,device_t child,uint32_t pin,unsigned int * value)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
gpiobus_pin_toggle(device_t dev,device_t child,uint32_t pin)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
gpiobus_pin_getname(device_t dev,uint32_t pin,char * name)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
gpiobus_pin_setname(device_t dev,uint32_t pin,const char * name)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,	bus_generic_rman_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