gpiobus.c revision 254988 
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: head/sys/dev/gpio/gpiobus.c 254988 2013-08-28 14:39:24Z 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 void gpiobus_print_pins(struct gpiobus_ivar *);
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 void gpiobus_lock_bus(device_t);
66static void gpiobus_unlock_bus(device_t);
67static void gpiobus_acquire_bus(device_t, device_t);
68static void gpiobus_release_bus(device_t, device_t);
69static int gpiobus_pin_setflags(device_t, device_t, uint32_t, uint32_t);
70static int gpiobus_pin_getflags(device_t, device_t, uint32_t, uint32_t*);
71static int gpiobus_pin_getcaps(device_t, device_t, uint32_t, uint32_t*);
72static int gpiobus_pin_set(device_t, device_t, uint32_t, unsigned int);
73static int gpiobus_pin_get(device_t, device_t, uint32_t, unsigned int*);
74static int gpiobus_pin_toggle(device_t, device_t, uint32_t);
75
76#define	GPIOBUS_LOCK(_sc) mtx_lock(&(_sc)->sc_mtx)
77#define	GPIOBUS_UNLOCK(_sc) mtx_unlock(&(_sc)->sc_mtx)
78#define	GPIOBUS_LOCK_INIT(_sc) \
79	mtx_init(&_sc->sc_mtx, device_get_nameunit(_sc->sc_dev), \
80	    "gpiobus", MTX_DEF)
81#define	GPIOBUS_LOCK_DESTROY(_sc) mtx_destroy(&_sc->sc_mtx);
82#define	GPIOBUS_ASSERT_LOCKED(_sc) mtx_assert(&_sc->sc_mtx, MA_OWNED);
83#define	GPIOBUS_ASSERT_UNLOCKED(_sc) mtx_assert(&_sc->sc_mtx, MA_NOTOWNED);
84
85
86static void
87gpiobus_print_pins(struct gpiobus_ivar *devi)
88{
89	int range_start, range_stop, need_coma;
90	int i;
91
92	if (devi->npins == 0)
93		return;
94
95	need_coma = 0;
96	range_start = range_stop = devi->pins[0];
97	for (i = 1; i < devi->npins; i++) {
98		if (devi->pins[i] != (range_stop + 1)) {
99			if (need_coma)
100				printf(",");
101			if (range_start != range_stop)
102				printf("%d-%d", range_start, range_stop);
103			else
104				printf("%d", range_start);
105
106			range_start = range_stop = devi->pins[i];
107			need_coma = 1;
108		}
109		else
110			range_stop++;
111	}
112
113	if (need_coma)
114		printf(",");
115	if (range_start != range_stop)
116		printf("%d-%d", range_start, range_stop);
117	else
118		printf("%d", range_start);
119}
120
121static int
122gpiobus_parse_pins(struct gpiobus_softc *sc, device_t child, int mask)
123{
124	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
125	int i, npins;
126
127	npins = 0;
128	for (i = 0; i < 32; i++) {
129		if (mask & (1 << i))
130			npins++;
131	}
132
133	if (npins == 0) {
134		device_printf(child, "empty pin mask");
135		return (EINVAL);
136	}
137
138	devi->npins = npins;
139	devi->pins = malloc(sizeof(uint32_t) * devi->npins, M_DEVBUF,
140	    M_NOWAIT | M_ZERO);
141
142	if (!devi->pins)
143		return (ENOMEM);
144
145	npins = 0;
146	for (i = 0; i < 32; i++) {
147
148		if ((mask & (1 << i)) == 0)
149			continue;
150
151		if (i >= sc->sc_npins) {
152			device_printf(child,
153			    "invalid pin %d, max: %d\n", i, sc->sc_npins - 1);
154			free(devi->pins, M_DEVBUF);
155			return (EINVAL);
156		}
157
158		devi->pins[npins++] = i;
159		/*
160		 * Mark pin as mapped and give warning if it's already mapped
161		 */
162		if (sc->sc_pins_mapped[i]) {
163			device_printf(child,
164			    "warning: pin %d is already mapped\n", i);
165			free(devi->pins, M_DEVBUF);
166			return (EINVAL);
167		}
168		sc->sc_pins_mapped[i] = 1;
169	}
170
171	return (0);
172}
173
174static int
175gpiobus_probe(device_t dev)
176{
177	device_set_desc(dev, "GPIO bus");
178	return (0);
179}
180
181static int
182gpiobus_attach(device_t dev)
183{
184	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
185	int res;
186
187	sc->sc_busdev = dev;
188	sc->sc_dev = device_get_parent(dev);
189	res = GPIO_PIN_MAX(sc->sc_dev, &sc->sc_npins);
190	if (res)
191		return (ENXIO);
192
193	/*
194	 * Increase to get number of pins
195	 */
196	sc->sc_npins++;
197
198	KASSERT(sc->sc_npins != 0, ("GPIO device with no pins"));
199
200	sc->sc_pins_mapped = malloc(sizeof(int) * sc->sc_npins, M_DEVBUF,
201	    M_NOWAIT | M_ZERO);
202
203	if (!sc->sc_pins_mapped)
204		return (ENOMEM);
205
206	/* init bus lock */
207	GPIOBUS_LOCK_INIT(sc);
208
209	/*
210	 * Get parent's pins and mark them as unmapped
211	 */
212	bus_enumerate_hinted_children(dev);
213	return (bus_generic_attach(dev));
214}
215
216/*
217 * Since this is not a self-enumerating bus, and since we always add
218 * children in attach, we have to always delete children here.
219 */
220static int
221gpiobus_detach(device_t dev)
222{
223	struct gpiobus_softc *sc;
224	struct gpiobus_ivar *devi;
225	device_t *devlist;
226	int i, err, ndevs;
227
228	sc = GPIOBUS_SOFTC(dev);
229	KASSERT(mtx_initialized(&sc->sc_mtx),
230	    ("gpiobus mutex not initialized"));
231	GPIOBUS_LOCK_DESTROY(sc);
232
233	if ((err = bus_generic_detach(dev)) != 0)
234		return (err);
235
236	if ((err = device_get_children(dev, &devlist, &ndevs)) != 0)
237		return (err);
238	for (i = 0; i < ndevs; i++) {
239		device_delete_child(dev, devlist[i]);
240		devi = GPIOBUS_IVAR(devlist[i]);
241		if (devi->pins) {
242			free(devi->pins, M_DEVBUF);
243			devi->pins = NULL;
244		}
245	}
246	free(devlist, M_TEMP);
247
248	if (sc->sc_pins_mapped) {
249		free(sc->sc_pins_mapped, M_DEVBUF);
250		sc->sc_pins_mapped = NULL;
251	}
252
253	return (0);
254}
255
256static int
257gpiobus_suspend(device_t dev)
258{
259
260	return (bus_generic_suspend(dev));
261}
262
263static int
264gpiobus_resume(device_t dev)
265{
266
267	return (bus_generic_resume(dev));
268}
269
270static int
271gpiobus_print_child(device_t dev, device_t child)
272{
273	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
274	int retval = 0;
275
276	retval += bus_print_child_header(dev, child);
277	retval += printf(" at pin(s) ");
278	gpiobus_print_pins(devi);
279	retval += bus_print_child_footer(dev, child);
280
281	return (retval);
282}
283
284static int
285gpiobus_child_location_str(device_t bus, device_t child, char *buf,
286    size_t buflen)
287{
288
289	snprintf(buf, buflen, "pins=?");
290	return (0);
291}
292
293static int
294gpiobus_child_pnpinfo_str(device_t bus, device_t child, char *buf,
295    size_t buflen)
296{
297
298	*buf = '\0';
299	return (0);
300}
301
302static device_t
303gpiobus_add_child(device_t dev, u_int order, const char *name, int unit)
304{
305	device_t child;
306	struct gpiobus_ivar *devi;
307
308	child = device_add_child_ordered(dev, order, name, unit);
309	if (child == NULL)
310		return (child);
311	devi = malloc(sizeof(struct gpiobus_ivar), M_DEVBUF, M_NOWAIT | M_ZERO);
312	if (devi == NULL) {
313		device_delete_child(dev, child);
314		return (0);
315	}
316	device_set_ivars(child, devi);
317	return (child);
318}
319
320static void
321gpiobus_hinted_child(device_t bus, const char *dname, int dunit)
322{
323	struct gpiobus_softc *sc = GPIOBUS_SOFTC(bus);
324	struct gpiobus_ivar *devi;
325	device_t child;
326	int pins;
327
328
329	child = BUS_ADD_CHILD(bus, 0, dname, dunit);
330	devi = GPIOBUS_IVAR(child);
331	resource_int_value(dname, dunit, "pins", &pins);
332	if (gpiobus_parse_pins(sc, child, pins))
333		device_delete_child(bus, child);
334}
335
336static void
337gpiobus_lock_bus(device_t busdev)
338{
339	struct gpiobus_softc *sc;
340
341	sc = device_get_softc(busdev);
342	GPIOBUS_ASSERT_UNLOCKED(sc);
343	GPIOBUS_LOCK(sc);
344}
345
346static void
347gpiobus_unlock_bus(device_t busdev)
348{
349	struct gpiobus_softc *sc;
350
351	sc = device_get_softc(busdev);
352	GPIOBUS_ASSERT_LOCKED(sc);
353	GPIOBUS_UNLOCK(sc);
354}
355
356static void
357gpiobus_acquire_bus(device_t busdev, device_t child)
358{
359	struct gpiobus_softc *sc;
360
361	sc = device_get_softc(busdev);
362	GPIOBUS_ASSERT_LOCKED(sc);
363
364	if (sc->sc_owner)
365		panic("gpiobus: cannot serialize the access to device.");
366	sc->sc_owner = child;
367}
368
369static void
370gpiobus_release_bus(device_t busdev, device_t child)
371{
372	struct gpiobus_softc *sc;
373
374	sc = device_get_softc(busdev);
375	GPIOBUS_ASSERT_LOCKED(sc);
376
377	if (!sc->sc_owner)
378		panic("gpiobus: releasing unowned bus.");
379	if (sc->sc_owner != child)
380		panic("gpiobus: you don't own the bus. game over.");
381
382	sc->sc_owner = NULL;
383}
384
385static int
386gpiobus_pin_setflags(device_t dev, device_t child, uint32_t pin,
387    uint32_t flags)
388{
389	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
390	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
391
392	if (pin >= devi->npins)
393		return (EINVAL);
394
395	return GPIO_PIN_SETFLAGS(sc->sc_dev, devi->pins[pin], flags);
396}
397
398static int
399gpiobus_pin_getflags(device_t dev, device_t child, uint32_t pin,
400    uint32_t *flags)
401{
402	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
403	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
404
405	if (pin >= devi->npins)
406		return (EINVAL);
407
408	return GPIO_PIN_GETFLAGS(sc->sc_dev, devi->pins[pin], flags);
409}
410
411static int
412gpiobus_pin_getcaps(device_t dev, device_t child, uint32_t pin,
413    uint32_t *caps)
414{
415	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
416	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
417
418	if (pin >= devi->npins)
419		return (EINVAL);
420
421	return GPIO_PIN_GETCAPS(sc->sc_dev, devi->pins[pin], caps);
422}
423
424static int
425gpiobus_pin_set(device_t dev, device_t child, uint32_t pin,
426    unsigned int value)
427{
428	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
429	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
430
431	if (pin >= devi->npins)
432		return (EINVAL);
433
434	return GPIO_PIN_SET(sc->sc_dev, devi->pins[pin], value);
435}
436
437static int
438gpiobus_pin_get(device_t dev, device_t child, uint32_t pin,
439    unsigned int *value)
440{
441	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
442	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
443
444	if (pin >= devi->npins)
445		return (EINVAL);
446
447	return GPIO_PIN_GET(sc->sc_dev, devi->pins[pin], value);
448}
449
450static int
451gpiobus_pin_toggle(device_t dev, device_t child, uint32_t pin)
452{
453	struct gpiobus_softc *sc = GPIOBUS_SOFTC(dev);
454	struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
455
456	if (pin >= devi->npins)
457		return (EINVAL);
458
459	return GPIO_PIN_TOGGLE(sc->sc_dev, devi->pins[pin]);
460}
461
462static device_method_t gpiobus_methods[] = {
463	/* Device interface */
464	DEVMETHOD(device_probe,		gpiobus_probe),
465	DEVMETHOD(device_attach,	gpiobus_attach),
466	DEVMETHOD(device_detach,	gpiobus_detach),
467	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
468	DEVMETHOD(device_suspend,	gpiobus_suspend),
469	DEVMETHOD(device_resume,	gpiobus_resume),
470
471	/* Bus interface */
472	DEVMETHOD(bus_add_child,	gpiobus_add_child),
473	DEVMETHOD(bus_print_child,	gpiobus_print_child),
474	DEVMETHOD(bus_child_pnpinfo_str, gpiobus_child_pnpinfo_str),
475	DEVMETHOD(bus_child_location_str, gpiobus_child_location_str),
476	DEVMETHOD(bus_hinted_child,	gpiobus_hinted_child),
477
478	/* GPIO protocol */
479	DEVMETHOD(gpiobus_lock_bus,	gpiobus_lock_bus),
480	DEVMETHOD(gpiobus_unlock_bus,	gpiobus_unlock_bus),
481	DEVMETHOD(gpiobus_acquire_bus,	gpiobus_acquire_bus),
482	DEVMETHOD(gpiobus_release_bus,	gpiobus_release_bus),
483	DEVMETHOD(gpiobus_pin_getflags,	gpiobus_pin_getflags),
484	DEVMETHOD(gpiobus_pin_getcaps,	gpiobus_pin_getcaps),
485	DEVMETHOD(gpiobus_pin_setflags,	gpiobus_pin_setflags),
486	DEVMETHOD(gpiobus_pin_get,	gpiobus_pin_get),
487	DEVMETHOD(gpiobus_pin_set,	gpiobus_pin_set),
488	DEVMETHOD(gpiobus_pin_toggle,	gpiobus_pin_toggle),
489
490	DEVMETHOD_END
491};
492
493driver_t gpiobus_driver = {
494	"gpiobus",
495	gpiobus_methods,
496	sizeof(struct gpiobus_softc)
497};
498
499devclass_t	gpiobus_devclass;
500
501DRIVER_MODULE(gpiobus, gpio, gpiobus_driver, gpiobus_devclass, 0, 0);
502MODULE_VERSION(gpiobus, 1);
503