gpiobus.c revision 266105 
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 266105 2014-05-15 01:27:53Z loos $");
29
30#include <sys/param.h>
31#include <sys/systm.h>
32#include <sys/malloc.h>
33#include <sys/module.h>
34#include <sys/kernel.h>
35#include <sys/queue.h>
36#include <sys/sysctl.h>
37#include <sys/types.h>
38
39#include <sys/bus.h>
40#include <machine/bus.h>
41#include <sys/rman.h>
42#include <machine/resource.h>
43
44#include <sys/gpio.h>
45#include <dev/gpio/gpiobusvar.h>
46#include "gpio_if.h"
47#include "gpiobus_if.h"
48
49static int gpiobus_parse_pins(struct gpiobus_softc *, device_t, int);
50static int gpiobus_probe(device_t);
51static int gpiobus_attach(device_t);
52static int gpiobus_detach(device_t);
53static int gpiobus_suspend(device_t);
54static int gpiobus_resume(device_t);
55static int gpiobus_print_child(device_t, device_t);
56static int gpiobus_child_location_str(device_t, device_t, char *, size_t);
57static int gpiobus_child_pnpinfo_str(device_t, device_t, char *, size_t);
58static device_t gpiobus_add_child(device_t, u_int, const char *, int);
59static void gpiobus_hinted_child(device_t, const char *, int);
60
61/*
62 * GPIOBUS interface
63 */
64static void gpiobus_lock_bus(device_t);
65static void gpiobus_unlock_bus(device_t);
66static void gpiobus_acquire_bus(device_t, device_t);
67static void gpiobus_release_bus(device_t, device_t);
68static int gpiobus_pin_setflags(device_t, device_t, uint32_t, uint32_t);
69static int gpiobus_pin_getflags(device_t, device_t, uint32_t, uint32_t*);
70static int gpiobus_pin_getcaps(device_t, device_t, uint32_t, uint32_t*);
71static int gpiobus_pin_set(device_t, device_t, uint32_t, unsigned int);
72static int gpiobus_pin_get(device_t, device_t, uint32_t, unsigned int*);
73static int gpiobus_pin_toggle(device_t, device_t, uint32_t);
74
75void
76gpiobus_print_pins(struct gpiobus_ivar *devi)
77{
78	int range_start, range_stop, need_coma;
79	int i;
80
81	if (devi->npins == 0)
82		return;
83
84	need_coma = 0;
85	range_start = range_stop = devi->pins[0];
86	for (i = 1; i < devi->npins; i++) {
87		if (devi->pins[i] != (range_stop + 1)) {
88			if (need_coma)
89				printf(",");
90			if (range_start != range_stop)
91				printf("%d-%d", range_start, range_stop);
92			else
93				printf("%d", range_start);
94
95			range_start = range_stop = devi->pins[i];
96			need_coma = 1;
97		}
98		else
99			range_stop++;
100	}
101
102	if (need_coma)
103		printf(",");
104	if (range_start != range_stop)
105		printf("%d-%d", range_start, range_stop);
106	else
107		printf("%d", range_start);
108}
109
110static int
111gpiobus_parse_pins(struct gpiobus_softc *sc, device_t child, int mask)
112{
113	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
114	int i, npins;
115
116	npins = 0;
117	for (i = 0; i < 32; i++) {
118		if (mask & (1 << i))
119			npins++;
120	}
121
122	if (npins == 0) {
123		device_printf(child, "empty pin mask\n");
124		return (EINVAL);
125	}
126
127	devi->npins = npins;
128	devi->pins = malloc(sizeof(uint32_t) * devi->npins, M_DEVBUF,
129	    M_NOWAIT | M_ZERO);
130
131	if (!devi->pins)
132		return (ENOMEM);
133
134	npins = 0;
135	for (i = 0; i < 32; i++) {
136
137		if ((mask & (1 << i)) == 0)
138			continue;
139
140		if (i >= sc->sc_npins) {
141			device_printf(child,
142			    "invalid pin %d, max: %d\n", i, sc->sc_npins - 1);
143			free(devi->pins, M_DEVBUF);
144			return (EINVAL);
145		}
146
147		devi->pins[npins++] = i;
148		/*
149		 * Mark pin as mapped and give warning if it's already mapped
150		 */
151		if (sc->sc_pins_mapped[i]) {
152			device_printf(child,
153			    "warning: pin %d is already mapped\n", i);
154			free(devi->pins, M_DEVBUF);
155			return (EINVAL);
156		}
157		sc->sc_pins_mapped[i] = 1;
158	}
159
160	return (0);
161}
162
163static int
164gpiobus_probe(device_t dev)
165{
166	device_set_desc(dev, "GPIO bus");
167
168	return (BUS_PROBE_GENERIC);
169}
170
171static int
172gpiobus_attach(device_t dev)
173{
174	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
175	int res;
176
177	sc->sc_busdev = dev;
178	sc->sc_dev = device_get_parent(dev);
179	res = GPIO_PIN_MAX(sc->sc_dev, &sc->sc_npins);
180	if (res)
181		return (ENXIO);
182
183	KASSERT(sc->sc_npins != 0, ("GPIO device with no pins"));
184
185	/*
186	 * Increase to get number of pins
187	 */
188	sc->sc_npins++;
189
190	sc->sc_pins_mapped = malloc(sizeof(int) * sc->sc_npins, M_DEVBUF,
191	    M_NOWAIT | M_ZERO);
192
193	if (!sc->sc_pins_mapped)
194		return (ENOMEM);
195
196	/* init bus lock */
197	GPIOBUS_LOCK_INIT(sc);
198
199	/*
200	 * Get parent's pins and mark them as unmapped
201	 */
202	bus_generic_probe(dev);
203	bus_enumerate_hinted_children(dev);
204
205	return (bus_generic_attach(dev));
206}
207
208/*
209 * Since this is not a self-enumerating bus, and since we always add
210 * children in attach, we have to always delete children here.
211 */
212static int
213gpiobus_detach(device_t dev)
214{
215	struct gpiobus_softc *sc;
216	struct gpiobus_ivar *devi;
217	device_t *devlist;
218	int i, err, ndevs;
219
220	sc = GPIOBUS_SOFTC(dev);
221	KASSERT(mtx_initialized(&sc->sc_mtx),
222	    ("gpiobus mutex not initialized"));
223	GPIOBUS_LOCK_DESTROY(sc);
224
225	if ((err = bus_generic_detach(dev)) != 0)
226		return (err);
227
228	if ((err = device_get_children(dev, &devlist, &ndevs)) != 0)
229		return (err);
230	for (i = 0; i < ndevs; i++) {
231		device_delete_child(dev, devlist[i]);
232		devi = GPIOBUS_IVAR(devlist[i]);
233		if (devi->pins) {
234			free(devi->pins, M_DEVBUF);
235			devi->pins = NULL;
236		}
237	}
238	free(devlist, M_TEMP);
239
240	if (sc->sc_pins_mapped) {
241		free(sc->sc_pins_mapped, M_DEVBUF);
242		sc->sc_pins_mapped = NULL;
243	}
244
245	return (0);
246}
247
248static int
249gpiobus_suspend(device_t dev)
250{
251
252	return (bus_generic_suspend(dev));
253}
254
255static int
256gpiobus_resume(device_t dev)
257{
258
259	return (bus_generic_resume(dev));
260}
261
262static int
263gpiobus_print_child(device_t dev, device_t child)
264{
265	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
266	int retval = 0;
267
268	retval += bus_print_child_header(dev, child);
269	retval += printf(" at pin(s) ");
270	gpiobus_print_pins(devi);
271	retval += bus_print_child_footer(dev, child);
272
273	return (retval);
274}
275
276static int
277gpiobus_child_location_str(device_t bus, device_t child, char *buf,
278    size_t buflen)
279{
280
281	snprintf(buf, buflen, "pins=?");
282	return (0);
283}
284
285static int
286gpiobus_child_pnpinfo_str(device_t bus, device_t child, char *buf,
287    size_t buflen)
288{
289
290	*buf = '\0';
291	return (0);
292}
293
294static device_t
295gpiobus_add_child(device_t dev, u_int order, const char *name, int unit)
296{
297	device_t child;
298	struct gpiobus_ivar *devi;
299
300	child = device_add_child_ordered(dev, order, name, unit);
301	if (child == NULL)
302		return (child);
303	devi = malloc(sizeof(struct gpiobus_ivar), M_DEVBUF, M_NOWAIT | M_ZERO);
304	if (devi == NULL) {
305		device_delete_child(dev, child);
306		return (0);
307	}
308	device_set_ivars(child, devi);
309	return (child);
310}
311
312static void
313gpiobus_hinted_child(device_t bus, const char *dname, int dunit)
314{
315	struct gpiobus_softc *sc = GPIOBUS_SOFTC(bus);
316	struct gpiobus_ivar *devi;
317	device_t child;
318	int pins;
319
320
321	child = BUS_ADD_CHILD(bus, 0, dname, dunit);
322	devi = GPIOBUS_IVAR(child);
323	resource_int_value(dname, dunit, "pins", &pins);
324	if (gpiobus_parse_pins(sc, child, pins))
325		device_delete_child(bus, child);
326}
327
328static void
329gpiobus_lock_bus(device_t busdev)
330{
331	struct gpiobus_softc *sc;
332
333	sc = device_get_softc(busdev);
334	GPIOBUS_ASSERT_UNLOCKED(sc);
335	GPIOBUS_LOCK(sc);
336}
337
338static void
339gpiobus_unlock_bus(device_t busdev)
340{
341	struct gpiobus_softc *sc;
342
343	sc = device_get_softc(busdev);
344	GPIOBUS_ASSERT_LOCKED(sc);
345	GPIOBUS_UNLOCK(sc);
346}
347
348static void
349gpiobus_acquire_bus(device_t busdev, device_t child)
350{
351	struct gpiobus_softc *sc;
352
353	sc = device_get_softc(busdev);
354	GPIOBUS_ASSERT_LOCKED(sc);
355
356	if (sc->sc_owner)
357		panic("gpiobus: cannot serialize the access to device.");
358	sc->sc_owner = child;
359}
360
361static void
362gpiobus_release_bus(device_t busdev, device_t child)
363{
364	struct gpiobus_softc *sc;
365
366	sc = device_get_softc(busdev);
367	GPIOBUS_ASSERT_LOCKED(sc);
368
369	if (!sc->sc_owner)
370		panic("gpiobus: releasing unowned bus.");
371	if (sc->sc_owner != child)
372		panic("gpiobus: you don't own the bus. game over.");
373
374	sc->sc_owner = NULL;
375}
376
377static int
378gpiobus_pin_setflags(device_t dev, device_t child, uint32_t pin,
379    uint32_t flags)
380{
381	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
382	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
383
384	if (pin >= devi->npins)
385		return (EINVAL);
386
387	return GPIO_PIN_SETFLAGS(sc->sc_dev, devi->pins[pin], flags);
388}
389
390static int
391gpiobus_pin_getflags(device_t dev, device_t child, uint32_t pin,
392    uint32_t *flags)
393{
394	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
395	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
396
397	if (pin >= devi->npins)
398		return (EINVAL);
399
400	return GPIO_PIN_GETFLAGS(sc->sc_dev, devi->pins[pin], flags);
401}
402
403static int
404gpiobus_pin_getcaps(device_t dev, device_t child, uint32_t pin,
405    uint32_t *caps)
406{
407	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
408	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
409
410	if (pin >= devi->npins)
411		return (EINVAL);
412
413	return GPIO_PIN_GETCAPS(sc->sc_dev, devi->pins[pin], caps);
414}
415
416static int
417gpiobus_pin_set(device_t dev, device_t child, uint32_t pin,
418    unsigned int value)
419{
420	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
421	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
422
423	if (pin >= devi->npins)
424		return (EINVAL);
425
426	return GPIO_PIN_SET(sc->sc_dev, devi->pins[pin], value);
427}
428
429static int
430gpiobus_pin_get(device_t dev, device_t child, uint32_t pin,
431    unsigned int *value)
432{
433	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
434	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
435
436	if (pin >= devi->npins)
437		return (EINVAL);
438
439	return GPIO_PIN_GET(sc->sc_dev, devi->pins[pin], value);
440}
441
442static int
443gpiobus_pin_toggle(device_t dev, device_t child, uint32_t pin)
444{
445	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
446	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
447
448	if (pin >= devi->npins)
449		return (EINVAL);
450
451	return GPIO_PIN_TOGGLE(sc->sc_dev, devi->pins[pin]);
452}
453
454static device_method_t gpiobus_methods[] = {
455	/* Device interface */
456	DEVMETHOD(device_probe,		gpiobus_probe),
457	DEVMETHOD(device_attach,	gpiobus_attach),
458	DEVMETHOD(device_detach,	gpiobus_detach),
459	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
460	DEVMETHOD(device_suspend,	gpiobus_suspend),
461	DEVMETHOD(device_resume,	gpiobus_resume),
462
463	/* Bus interface */
464	DEVMETHOD(bus_add_child,	gpiobus_add_child),
465	DEVMETHOD(bus_print_child,	gpiobus_print_child),
466	DEVMETHOD(bus_child_pnpinfo_str, gpiobus_child_pnpinfo_str),
467	DEVMETHOD(bus_child_location_str, gpiobus_child_location_str),
468	DEVMETHOD(bus_hinted_child,	gpiobus_hinted_child),
469
470	/* GPIO protocol */
471	DEVMETHOD(gpiobus_lock_bus,	gpiobus_lock_bus),
472	DEVMETHOD(gpiobus_unlock_bus,	gpiobus_unlock_bus),
473	DEVMETHOD(gpiobus_acquire_bus,	gpiobus_acquire_bus),
474	DEVMETHOD(gpiobus_release_bus,	gpiobus_release_bus),
475	DEVMETHOD(gpiobus_pin_getflags,	gpiobus_pin_getflags),
476	DEVMETHOD(gpiobus_pin_getcaps,	gpiobus_pin_getcaps),
477	DEVMETHOD(gpiobus_pin_setflags,	gpiobus_pin_setflags),
478	DEVMETHOD(gpiobus_pin_get,	gpiobus_pin_get),
479	DEVMETHOD(gpiobus_pin_set,	gpiobus_pin_set),
480	DEVMETHOD(gpiobus_pin_toggle,	gpiobus_pin_toggle),
481
482	DEVMETHOD_END
483};
484
485driver_t gpiobus_driver = {
486	"gpiobus",
487	gpiobus_methods,
488	sizeof(struct gpiobus_softc)
489};
490
491devclass_t	gpiobus_devclass;
492
493DRIVER_MODULE(gpiobus, gpio, gpiobus_driver, gpiobus_devclass, 0, 0);
494MODULE_VERSION(gpiobus, 1);
495