gpiobus.c revision 278786 
1/*-
2 * Copyright (c) 2009 Oleksandr Tymoshenko <gonzo@freebsd.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD: stable/10/sys/dev/gpio/gpiobus.c 278786 2015-02-14 21:16:19Z loos $");
29
30#include <sys/param.h>
31#include <sys/systm.h>
32#include <sys/bus.h>
33#include <sys/gpio.h>
34#include <sys/kernel.h>
35#include <sys/malloc.h>
36#include <sys/module.h>
37
38#include <dev/gpio/gpiobusvar.h>
39
40#include "gpiobus_if.h"
41
42#undef GPIOBUS_DEBUG
43#ifdef GPIOBUS_DEBUG
44#define	dprintf printf
45#else
46#define	dprintf(x, arg...)
47#endif
48
49static void gpiobus_print_pins(struct gpiobus_ivar *, char *, size_t);
50static int gpiobus_parse_pins(struct gpiobus_softc *, device_t, int);
51static int gpiobus_probe(device_t);
52static int gpiobus_attach(device_t);
53static int gpiobus_detach(device_t);
54static int gpiobus_suspend(device_t);
55static int gpiobus_resume(device_t);
56static int gpiobus_print_child(device_t, device_t);
57static int gpiobus_child_location_str(device_t, device_t, char *, size_t);
58static int gpiobus_child_pnpinfo_str(device_t, device_t, char *, size_t);
59static device_t gpiobus_add_child(device_t, u_int, const char *, int);
60static void gpiobus_hinted_child(device_t, const char *, int);
61
62/*
63 * GPIOBUS interface
64 */
65static int gpiobus_acquire_bus(device_t, device_t, int);
66static void gpiobus_release_bus(device_t, device_t);
67static int gpiobus_pin_setflags(device_t, device_t, uint32_t, uint32_t);
68static int gpiobus_pin_getflags(device_t, device_t, uint32_t, uint32_t*);
69static int gpiobus_pin_getcaps(device_t, device_t, uint32_t, uint32_t*);
70static int gpiobus_pin_set(device_t, device_t, uint32_t, unsigned int);
71static int gpiobus_pin_get(device_t, device_t, uint32_t, unsigned int*);
72static int gpiobus_pin_toggle(device_t, device_t, uint32_t);
73
74int
75gpio_check_flags(uint32_t caps, uint32_t flags)
76{
77
78	/* Check for unwanted flags. */
79	if ((flags & caps) == 0 || (flags & caps) != flags)
80		return (EINVAL);
81	/* Cannot mix input/output together. */
82	if (flags & GPIO_PIN_INPUT && flags & GPIO_PIN_OUTPUT)
83		return (EINVAL);
84	/* Cannot mix pull-up/pull-down together. */
85	if (flags & GPIO_PIN_PULLUP && flags & GPIO_PIN_PULLDOWN)
86		return (EINVAL);
87
88	return (0);
89}
90
91static void
92gpiobus_print_pins(struct gpiobus_ivar *devi, char *buf, size_t buflen)
93{
94	char tmp[128];
95	int i, range_start, range_stop, need_coma;
96
97	if (devi->npins == 0)
98		return;
99
100	need_coma = 0;
101	range_start = range_stop = devi->pins[0];
102	for (i = 1; i < devi->npins; i++) {
103		if (devi->pins[i] != (range_stop + 1)) {
104			if (need_coma)
105				strlcat(buf, ",", buflen);
106			memset(tmp, 0, sizeof(tmp));
107			if (range_start != range_stop)
108				snprintf(tmp, sizeof(tmp) - 1, "%d-%d",
109				    range_start, range_stop);
110			else
111				snprintf(tmp, sizeof(tmp) - 1, "%d",
112				    range_start);
113			strlcat(buf, tmp, buflen);
114
115			range_start = range_stop = devi->pins[i];
116			need_coma = 1;
117		}
118		else
119			range_stop++;
120	}
121
122	if (need_coma)
123		strlcat(buf, ",", buflen);
124	memset(tmp, 0, sizeof(tmp));
125	if (range_start != range_stop)
126		snprintf(tmp, sizeof(tmp) - 1, "%d-%d",
127		    range_start, range_stop);
128	else
129		snprintf(tmp, sizeof(tmp) - 1, "%d",
130		    range_start);
131	strlcat(buf, tmp, buflen);
132}
133
134int
135gpiobus_init_softc(device_t dev)
136{
137	struct gpiobus_softc *sc;
138
139	sc = GPIOBUS_SOFTC(dev);
140	sc->sc_busdev = dev;
141	sc->sc_dev = device_get_parent(dev);
142	sc->sc_intr_rman.rm_type = RMAN_ARRAY;
143	sc->sc_intr_rman.rm_descr = "GPIO Interrupts";
144	if (rman_init(&sc->sc_intr_rman) != 0 ||
145	    rman_manage_region(&sc->sc_intr_rman, 0, ~0) != 0)
146		panic("%s: failed to set up rman.", __func__);
147
148	if (GPIO_PIN_MAX(sc->sc_dev, &sc->sc_npins) != 0)
149		return (ENXIO);
150
151	KASSERT(sc->sc_npins != 0, ("GPIO device with no pins"));
152
153	/* Pins = GPIO_PIN_MAX() + 1 */
154	sc->sc_npins++;
155
156	sc->sc_pins_mapped = malloc(sizeof(int) * sc->sc_npins, M_DEVBUF,
157	    M_NOWAIT | M_ZERO);
158	if (sc->sc_pins_mapped == NULL)
159		return (ENOMEM);
160
161	/* Initialize the bus lock. */
162	GPIOBUS_LOCK_INIT(sc);
163
164	return (0);
165}
166
167static int
168gpiobus_parse_pins(struct gpiobus_softc *sc, device_t child, int mask)
169{
170	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
171	int i, npins;
172
173	npins = 0;
174	for (i = 0; i < 32; i++) {
175		if (mask & (1 << i))
176			npins++;
177	}
178
179	if (npins == 0) {
180		device_printf(child, "empty pin mask\n");
181		return (EINVAL);
182	}
183
184	devi->npins = npins;
185	devi->pins = malloc(sizeof(uint32_t) * devi->npins, M_DEVBUF,
186	    M_NOWAIT | M_ZERO);
187
188	if (!devi->pins)
189		return (ENOMEM);
190
191	npins = 0;
192	for (i = 0; i < 32; i++) {
193
194		if ((mask & (1 << i)) == 0)
195			continue;
196
197		if (i >= sc->sc_npins) {
198			device_printf(child,
199			    "invalid pin %d, max: %d\n", i, sc->sc_npins - 1);
200			free(devi->pins, M_DEVBUF);
201			return (EINVAL);
202		}
203
204		devi->pins[npins++] = i;
205		/*
206		 * Mark pin as mapped and give warning if it's already mapped
207		 */
208		if (sc->sc_pins_mapped[i]) {
209			device_printf(child,
210			    "warning: pin %d is already mapped\n", i);
211			free(devi->pins, M_DEVBUF);
212			return (EINVAL);
213		}
214		sc->sc_pins_mapped[i] = 1;
215	}
216
217	return (0);
218}
219
220static int
221gpiobus_probe(device_t dev)
222{
223	device_set_desc(dev, "GPIO bus");
224
225	return (BUS_PROBE_GENERIC);
226}
227
228static int
229gpiobus_attach(device_t dev)
230{
231	int err;
232
233	err = gpiobus_init_softc(dev);
234	if (err != 0)
235		return (err);
236
237	/*
238	 * Get parent's pins and mark them as unmapped
239	 */
240	bus_generic_probe(dev);
241	bus_enumerate_hinted_children(dev);
242
243	return (bus_generic_attach(dev));
244}
245
246/*
247 * Since this is not a self-enumerating bus, and since we always add
248 * children in attach, we have to always delete children here.
249 */
250static int
251gpiobus_detach(device_t dev)
252{
253	struct gpiobus_softc *sc;
254	struct gpiobus_ivar *devi;
255	device_t *devlist;
256	int i, err, ndevs;
257
258	sc = GPIOBUS_SOFTC(dev);
259	KASSERT(mtx_initialized(&sc->sc_mtx),
260	    ("gpiobus mutex not initialized"));
261	GPIOBUS_LOCK_DESTROY(sc);
262
263	if ((err = bus_generic_detach(dev)) != 0)
264		return (err);
265
266	if ((err = device_get_children(dev, &devlist, &ndevs)) != 0)
267		return (err);
268	for (i = 0; i < ndevs; i++) {
269		device_delete_child(dev, devlist[i]);
270		devi = GPIOBUS_IVAR(devlist[i]);
271		if (devi->pins) {
272			free(devi->pins, M_DEVBUF);
273			devi->pins = NULL;
274		}
275	}
276	free(devlist, M_TEMP);
277
278	if (sc->sc_pins_mapped) {
279		free(sc->sc_pins_mapped, M_DEVBUF);
280		sc->sc_pins_mapped = NULL;
281	}
282
283	return (0);
284}
285
286static int
287gpiobus_suspend(device_t dev)
288{
289
290	return (bus_generic_suspend(dev));
291}
292
293static int
294gpiobus_resume(device_t dev)
295{
296
297	return (bus_generic_resume(dev));
298}
299
300static int
301gpiobus_print_child(device_t dev, device_t child)
302{
303	char pins[128];
304	int retval = 0;
305	struct gpiobus_ivar *devi;
306
307	devi = GPIOBUS_IVAR(child);
308	memset(pins, 0, sizeof(pins));
309	retval += bus_print_child_header(dev, child);
310	retval += printf(" at pin(s) ");
311	gpiobus_print_pins(devi, pins, sizeof(pins));
312	retval += printf("%s", pins);
313	resource_list_print_type(&devi->rl, "irq", SYS_RES_IRQ, "%ld");
314	retval += bus_print_child_footer(dev, child);
315
316	return (retval);
317}
318
319static int
320gpiobus_child_location_str(device_t bus, device_t child, char *buf,
321    size_t buflen)
322{
323	struct gpiobus_ivar *devi;
324
325	devi = GPIOBUS_IVAR(child);
326	strlcpy(buf, "pin(s)=", buflen);
327	gpiobus_print_pins(devi, buf, buflen);
328
329	return (0);
330}
331
332static int
333gpiobus_child_pnpinfo_str(device_t bus, device_t child, char *buf,
334    size_t buflen)
335{
336
337	*buf = '\0';
338	return (0);
339}
340
341static device_t
342gpiobus_add_child(device_t dev, u_int order, const char *name, int unit)
343{
344	device_t child;
345	struct gpiobus_ivar *devi;
346
347	child = device_add_child_ordered(dev, order, name, unit);
348	if (child == NULL)
349		return (child);
350	devi = malloc(sizeof(struct gpiobus_ivar), M_DEVBUF, M_NOWAIT | M_ZERO);
351	if (devi == NULL) {
352		device_delete_child(dev, child);
353		return (0);
354	}
355	resource_list_init(&devi->rl);
356	device_set_ivars(child, devi);
357
358	return (child);
359}
360
361static void
362gpiobus_hinted_child(device_t bus, const char *dname, int dunit)
363{
364	struct gpiobus_softc *sc = GPIOBUS_SOFTC(bus);
365	struct gpiobus_ivar *devi;
366	device_t child;
367	int irq, pins;
368
369	child = BUS_ADD_CHILD(bus, 0, dname, dunit);
370	devi = GPIOBUS_IVAR(child);
371	resource_int_value(dname, dunit, "pins", &pins);
372	if (gpiobus_parse_pins(sc, child, pins))
373		device_delete_child(bus, child);
374	if (resource_int_value(dname, dunit, "irq", &irq) == 0) {
375		if (bus_set_resource(child, SYS_RES_IRQ, 0, irq, 1) != 0)
376			device_printf(bus,
377			    "warning: bus_set_resource() failed\n");
378	}
379}
380
381static int
382gpiobus_set_resource(device_t dev, device_t child, int type, int rid,
383    u_long start, u_long count)
384{
385	struct gpiobus_ivar *devi;
386	struct resource_list_entry *rle;
387
388	dprintf("%s: entry (%p, %p, %d, %d, %p, %ld)\n",
389	    __func__, dev, child, type, rid, (void *)(intptr_t)start, count);
390	devi = GPIOBUS_IVAR(child);
391	rle = resource_list_add(&devi->rl, type, rid, start,
392	    start + count - 1, count);
393	if (rle == NULL)
394		return (ENXIO);
395
396	return (0);
397}
398
399static struct resource *
400gpiobus_alloc_resource(device_t bus, device_t child, int type, int *rid,
401    u_long start, u_long end, u_long count, u_int flags)
402{
403	struct gpiobus_softc *sc;
404	struct resource *rv;
405	struct resource_list *rl;
406	struct resource_list_entry *rle;
407	int isdefault;
408
409	if (type != SYS_RES_IRQ)
410		return (NULL);
411	isdefault = (start == 0UL && end == ~0UL && count == 1);
412	rle = NULL;
413	if (isdefault) {
414		rl = BUS_GET_RESOURCE_LIST(bus, child);
415		if (rl == NULL)
416			return (NULL);
417		rle = resource_list_find(rl, type, *rid);
418		if (rle == NULL)
419			return (NULL);
420		if (rle->res != NULL)
421			panic("%s: resource entry is busy", __func__);
422		start = rle->start;
423		count = rle->count;
424		end = rle->end;
425	}
426	sc = device_get_softc(bus);
427	rv = rman_reserve_resource(&sc->sc_intr_rman, start, end, count, flags,
428	    child);
429	if (rv == NULL)
430		return (NULL);
431	rman_set_rid(rv, *rid);
432	if ((flags & RF_ACTIVE) != 0 &&
433	    bus_activate_resource(child, type, *rid, rv) != 0) {
434		rman_release_resource(rv);
435		return (NULL);
436	}
437
438	return (rv);
439}
440
441static int
442gpiobus_release_resource(device_t bus __unused, device_t child, int type,
443    int rid, struct resource *r)
444{
445	int error;
446
447	if (rman_get_flags(r) & RF_ACTIVE) {
448		error = bus_deactivate_resource(child, type, rid, r);
449		if (error)
450			return (error);
451	}
452
453	return (rman_release_resource(r));
454}
455
456static struct resource_list *
457gpiobus_get_resource_list(device_t bus __unused, device_t child)
458{
459	struct gpiobus_ivar *ivar;
460
461	ivar = GPIOBUS_IVAR(child);
462
463	return (&ivar->rl);
464}
465
466static int
467gpiobus_acquire_bus(device_t busdev, device_t child, int how)
468{
469	struct gpiobus_softc *sc;
470
471	sc = device_get_softc(busdev);
472	GPIOBUS_ASSERT_UNLOCKED(sc);
473	GPIOBUS_LOCK(sc);
474	if (sc->sc_owner != NULL) {
475		if (how == GPIOBUS_DONTWAIT) {
476			GPIOBUS_UNLOCK(sc);
477			return (EWOULDBLOCK);
478		}
479		while (sc->sc_owner != NULL)
480			mtx_sleep(sc, &sc->sc_mtx, 0, "gpiobuswait", 0);
481	}
482	sc->sc_owner = child;
483	GPIOBUS_UNLOCK(sc);
484
485	return (0);
486}
487
488static void
489gpiobus_release_bus(device_t busdev, device_t child)
490{
491	struct gpiobus_softc *sc;
492
493	sc = device_get_softc(busdev);
494	GPIOBUS_ASSERT_UNLOCKED(sc);
495	GPIOBUS_LOCK(sc);
496	if (sc->sc_owner == NULL)
497		panic("gpiobus: releasing unowned bus.");
498	if (sc->sc_owner != child)
499		panic("gpiobus: you don't own the bus. game over.");
500	sc->sc_owner = NULL;
501	wakeup(sc);
502	GPIOBUS_UNLOCK(sc);
503}
504
505static int
506gpiobus_pin_setflags(device_t dev, device_t child, uint32_t pin,
507    uint32_t flags)
508{
509	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
510	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
511	uint32_t caps;
512
513	if (pin >= devi->npins)
514		return (EINVAL);
515	if (GPIO_PIN_GETCAPS(sc->sc_dev, devi->pins[pin], &caps) != 0)
516		return (EINVAL);
517	if (gpio_check_flags(caps, flags) != 0)
518		return (EINVAL);
519
520	return (GPIO_PIN_SETFLAGS(sc->sc_dev, devi->pins[pin], flags));
521}
522
523static int
524gpiobus_pin_getflags(device_t dev, device_t child, uint32_t pin,
525    uint32_t *flags)
526{
527	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
528	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
529
530	if (pin >= devi->npins)
531		return (EINVAL);
532
533	return GPIO_PIN_GETFLAGS(sc->sc_dev, devi->pins[pin], flags);
534}
535
536static int
537gpiobus_pin_getcaps(device_t dev, device_t child, uint32_t pin,
538    uint32_t *caps)
539{
540	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
541	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
542
543	if (pin >= devi->npins)
544		return (EINVAL);
545
546	return GPIO_PIN_GETCAPS(sc->sc_dev, devi->pins[pin], caps);
547}
548
549static int
550gpiobus_pin_set(device_t dev, device_t child, uint32_t pin,
551    unsigned int value)
552{
553	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
554	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
555
556	if (pin >= devi->npins)
557		return (EINVAL);
558
559	return GPIO_PIN_SET(sc->sc_dev, devi->pins[pin], value);
560}
561
562static int
563gpiobus_pin_get(device_t dev, device_t child, uint32_t pin,
564    unsigned int *value)
565{
566	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
567	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
568
569	if (pin >= devi->npins)
570		return (EINVAL);
571
572	return GPIO_PIN_GET(sc->sc_dev, devi->pins[pin], value);
573}
574
575static int
576gpiobus_pin_toggle(device_t dev, device_t child, uint32_t pin)
577{
578	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
579	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
580
581	if (pin >= devi->npins)
582		return (EINVAL);
583
584	return GPIO_PIN_TOGGLE(sc->sc_dev, devi->pins[pin]);
585}
586
587static device_method_t gpiobus_methods[] = {
588	/* Device interface */
589	DEVMETHOD(device_probe,		gpiobus_probe),
590	DEVMETHOD(device_attach,	gpiobus_attach),
591	DEVMETHOD(device_detach,	gpiobus_detach),
592	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
593	DEVMETHOD(device_suspend,	gpiobus_suspend),
594	DEVMETHOD(device_resume,	gpiobus_resume),
595
596	/* Bus interface */
597	DEVMETHOD(bus_setup_intr,	bus_generic_setup_intr),
598	DEVMETHOD(bus_config_intr,	bus_generic_config_intr),
599	DEVMETHOD(bus_teardown_intr,	bus_generic_teardown_intr),
600	DEVMETHOD(bus_set_resource,	gpiobus_set_resource),
601	DEVMETHOD(bus_alloc_resource,	gpiobus_alloc_resource),
602	DEVMETHOD(bus_release_resource,	gpiobus_release_resource),
603	DEVMETHOD(bus_activate_resource,	bus_generic_activate_resource),
604	DEVMETHOD(bus_deactivate_resource,	bus_generic_deactivate_resource),
605	DEVMETHOD(bus_get_resource_list,	gpiobus_get_resource_list),
606	DEVMETHOD(bus_add_child,	gpiobus_add_child),
607	DEVMETHOD(bus_print_child,	gpiobus_print_child),
608	DEVMETHOD(bus_child_pnpinfo_str, gpiobus_child_pnpinfo_str),
609	DEVMETHOD(bus_child_location_str, gpiobus_child_location_str),
610	DEVMETHOD(bus_hinted_child,	gpiobus_hinted_child),
611
612	/* GPIO protocol */
613	DEVMETHOD(gpiobus_acquire_bus,	gpiobus_acquire_bus),
614	DEVMETHOD(gpiobus_release_bus,	gpiobus_release_bus),
615	DEVMETHOD(gpiobus_pin_getflags,	gpiobus_pin_getflags),
616	DEVMETHOD(gpiobus_pin_getcaps,	gpiobus_pin_getcaps),
617	DEVMETHOD(gpiobus_pin_setflags,	gpiobus_pin_setflags),
618	DEVMETHOD(gpiobus_pin_get,	gpiobus_pin_get),
619	DEVMETHOD(gpiobus_pin_set,	gpiobus_pin_set),
620	DEVMETHOD(gpiobus_pin_toggle,	gpiobus_pin_toggle),
621
622	DEVMETHOD_END
623};
624
625driver_t gpiobus_driver = {
626	"gpiobus",
627	gpiobus_methods,
628	sizeof(struct gpiobus_softc)
629};
630
631devclass_t	gpiobus_devclass;
632
633DRIVER_MODULE(gpiobus, gpio, gpiobus_driver, gpiobus_devclass, 0, 0);
634MODULE_VERSION(gpiobus, 1);
635