xref: /freebsd/sys/arm/freescale/imx/imx_gpio.c (revision 8ef24a0d4b28fe230e20637f56869cc4148cd2ca)
1 /*-
2  * Copyright (c) 2012, 2013 The FreeBSD Foundation
3  * All rights reserved.
4  *
5  * This software was developed by Oleksandr Rybalko under sponsorship
6  * from the FreeBSD Foundation.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1.	Redistributions of source code must retain the above copyright
12  *	notice, this list of conditions and the following disclaimer.
13  * 2.	Redistributions in binary form must reproduce the above copyright
14  *	notice, this list of conditions and the following disclaimer in the
15  *	documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 /*
31  * Freescale i.MX515 GPIO driver.
32  */
33 
34 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD$");
36 
37 #include "opt_platform.h"
38 
39 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/bus.h>
42 
43 #include <sys/kernel.h>
44 #include <sys/module.h>
45 #include <sys/rman.h>
46 #include <sys/lock.h>
47 #include <sys/mutex.h>
48 #include <sys/gpio.h>
49 #include <sys/proc.h>
50 
51 #include <machine/bus.h>
52 #include <machine/intr.h>
53 #include <machine/resource.h>
54 
55 #include <dev/fdt/fdt_common.h>
56 #include <dev/gpio/gpiobusvar.h>
57 #include <dev/ofw/openfirm.h>
58 #include <dev/ofw/ofw_bus.h>
59 #include <dev/ofw/ofw_bus_subr.h>
60 
61 #include "gpio_if.h"
62 
63 #ifdef INTRNG
64 #include "pic_if.h"
65 #endif
66 
67 #define	WRITE4(_sc, _r, _v)						\
68 	    bus_space_write_4((_sc)->sc_iot, (_sc)->sc_ioh, (_r), (_v))
69 #define	READ4(_sc, _r)							\
70 	    bus_space_read_4((_sc)->sc_iot, (_sc)->sc_ioh, (_r))
71 #define	SET4(_sc, _r, _m)						\
72 	    WRITE4((_sc), (_r), READ4((_sc), (_r)) | (_m))
73 #define	CLEAR4(_sc, _r, _m)						\
74 	    WRITE4((_sc), (_r), READ4((_sc), (_r)) & ~(_m))
75 
76 /* Registers definition for Freescale i.MX515 GPIO controller */
77 
78 #define	IMX_GPIO_DR_REG		0x000 /* Pin Data */
79 #define	IMX_GPIO_OE_REG		0x004 /* Set Pin Output */
80 #define	IMX_GPIO_PSR_REG	0x008 /* Pad Status */
81 #define	IMX_GPIO_ICR1_REG	0x00C /* Interrupt Configuration */
82 #define	IMX_GPIO_ICR2_REG	0x010 /* Interrupt Configuration */
83 #define		GPIO_ICR_COND_LOW	0
84 #define		GPIO_ICR_COND_HIGH	1
85 #define		GPIO_ICR_COND_RISE	2
86 #define		GPIO_ICR_COND_FALL	3
87 #define	IMX_GPIO_IMR_REG	0x014 /* Interrupt Mask Register */
88 #define	IMX_GPIO_ISR_REG	0x018 /* Interrupt Status Register */
89 #define	IMX_GPIO_EDGE_REG	0x01C /* Edge Detect Register */
90 
91 #define	DEFAULT_CAPS	(GPIO_PIN_INPUT | GPIO_PIN_OUTPUT)
92 #define	NGPIO		32
93 
94 #ifdef INTRNG
95 struct gpio_irqsrc {
96 	struct intr_irqsrc	gi_isrc;
97 	u_int			gi_irq;
98 	enum intr_polarity	gi_pol;
99 	enum intr_trigger	gi_trig;
100 };
101 #endif
102 
103 struct imx51_gpio_softc {
104 	device_t		dev;
105 	device_t		sc_busdev;
106 	struct mtx		sc_mtx;
107 	struct resource		*sc_res[3]; /* 1 x mem, 2 x IRQ */
108 	void			*gpio_ih[2];
109 	bus_space_tag_t		sc_iot;
110 	bus_space_handle_t	sc_ioh;
111 	int			gpio_npins;
112 	struct gpio_pin		gpio_pins[NGPIO];
113 #ifdef INTRNG
114 	struct gpio_irqsrc 	gpio_pic_irqsrc[NGPIO];
115 #endif
116 };
117 
118 static struct ofw_compat_data compat_data[] = {
119 	{"fsl,imx6q-gpio",  1},
120 	{"fsl,imx53-gpio",  1},
121 	{"fsl,imx51-gpio",  1},
122 	{NULL,	            0}
123 };
124 
125 static struct resource_spec imx_gpio_spec[] = {
126 	{ SYS_RES_MEMORY,	0,	RF_ACTIVE },
127 	{ SYS_RES_IRQ,		0,	RF_ACTIVE },
128 	{ SYS_RES_IRQ,		1,	RF_ACTIVE },
129 	{ -1, 0 }
130 };
131 
132 /*
133  * Helpers
134  */
135 static void imx51_gpio_pin_configure(struct imx51_gpio_softc *,
136     struct gpio_pin *, uint32_t);
137 
138 /*
139  * Driver stuff
140  */
141 static int imx51_gpio_probe(device_t);
142 static int imx51_gpio_attach(device_t);
143 static int imx51_gpio_detach(device_t);
144 
145 /*
146  * GPIO interface
147  */
148 static device_t imx51_gpio_get_bus(device_t);
149 static int imx51_gpio_pin_max(device_t, int *);
150 static int imx51_gpio_pin_getcaps(device_t, uint32_t, uint32_t *);
151 static int imx51_gpio_pin_getflags(device_t, uint32_t, uint32_t *);
152 static int imx51_gpio_pin_getname(device_t, uint32_t, char *);
153 static int imx51_gpio_pin_setflags(device_t, uint32_t, uint32_t);
154 static int imx51_gpio_pin_set(device_t, uint32_t, unsigned int);
155 static int imx51_gpio_pin_get(device_t, uint32_t, unsigned int *);
156 static int imx51_gpio_pin_toggle(device_t, uint32_t pin);
157 
158 #ifdef INTRNG
159 static int
160 gpio_pic_map_fdt(device_t dev, u_int ncells, pcell_t *cells, u_int *irqp,
161     enum intr_polarity *polp, enum intr_trigger *trigp)
162 {
163 	struct imx51_gpio_softc *sc;
164 	u_int irq, tripol;
165 	enum intr_polarity pol;
166 	enum intr_trigger trig;
167 
168 	sc = device_get_softc(dev);
169 
170 	/*
171 	 * From devicetree/bindings/gpio/fsl-imx-gpio.txt:
172 	 *  #interrupt-cells:  2. The first cell is the GPIO number. The second
173 	 *  cell bits[3:0] is used to specify trigger type and level flags:
174 	 *    1 = low-to-high edge triggered.
175 	 *    2 = high-to-low edge triggered.
176 	 *    4 = active high level-sensitive.
177 	 *    8 = active low level-sensitive.
178          * We can do any single one of these modes, but nothing in combo.
179 	 */
180 
181 	if (ncells != 2) {
182 		device_printf(sc->dev, "Invalid #interrupt-cells");
183 		return (EINVAL);
184 	}
185 
186 	irq = cells[0];
187 	tripol = cells[1];
188 	if (irq >= sc->gpio_npins) {
189 		device_printf(sc->dev, "Invalid interrupt number %d", irq);
190 		return (EINVAL);
191 	}
192 	switch (tripol) {
193 	case 1:
194 		trig = INTR_TRIGGER_EDGE;
195 		pol  = INTR_POLARITY_HIGH;
196 		break;
197 	case 2:
198 		trig = INTR_TRIGGER_EDGE;
199 		pol  = INTR_POLARITY_LOW;
200 		break;
201 	case 4:
202 		trig = INTR_TRIGGER_LEVEL;
203 		pol  = INTR_POLARITY_HIGH;
204 		break;
205 	case 8:
206 		trig = INTR_TRIGGER_LEVEL;
207 		pol  = INTR_POLARITY_LOW;
208 		break;
209 	default:
210 		device_printf(sc->dev, "unsupported trigger/polarity 0x%2x\n",
211 		    tripol);
212 		return (ENOTSUP);
213 	}
214 	*irqp = irq;
215 	if (polp != NULL)
216 		*polp = pol;
217 	if (trigp != NULL)
218 		*trigp = trig;
219 	return (0);
220 }
221 
222 static int
223 gpio_pic_map_intr(device_t dev, struct intr_map_data *data,
224     struct intr_irqsrc **isrcp)
225 {
226 	int error;
227 	u_int irq;
228 	struct intr_map_data_fdt *daf;
229 	struct imx51_gpio_softc *sc;
230 
231 	if (data->type != INTR_MAP_DATA_FDT)
232 		return (ENOTSUP);
233 
234 	daf = (struct intr_map_data_fdt *)data;
235 	error = gpio_pic_map_fdt(dev, daf->ncells, daf->cells, &irq, NULL,
236 	    NULL);
237 	if (error == 0) {
238 		sc = device_get_softc(dev);
239 		*isrcp = &sc->gpio_pic_irqsrc[irq].gi_isrc;
240 	}
241 	return (error);
242 }
243 
244 static int
245 gpio_pic_teardown_intr(device_t dev, struct intr_irqsrc *isrc,
246     struct resource *res, struct intr_map_data *data)
247 {
248 	struct imx51_gpio_softc *sc;
249 	struct gpio_irqsrc *gi;
250 
251 	sc = device_get_softc(dev);
252 	if (isrc->isrc_handlers == 0) {
253 		gi = (struct gpio_irqsrc *)isrc;
254 		gi->gi_pol = INTR_POLARITY_CONFORM;
255 		gi->gi_trig = INTR_TRIGGER_CONFORM;
256 
257 		// XXX Not sure this is necessary
258 		mtx_lock_spin(&sc->sc_mtx);
259 		CLEAR4(sc, IMX_GPIO_IMR_REG, (1U << gi->gi_irq));
260 		WRITE4(sc, IMX_GPIO_ISR_REG, (1U << gi->gi_irq));
261 		mtx_unlock_spin(&sc->sc_mtx);
262 	}
263 	return (0);
264 }
265 
266 static int
267 gpio_pic_setup_intr(device_t dev, struct intr_irqsrc *isrc,
268     struct resource *res, struct intr_map_data *data)
269 {
270 	struct intr_map_data_fdt *daf;
271 	struct imx51_gpio_softc *sc;
272 	struct gpio_irqsrc *gi;
273 	int error, icfg;
274 	u_int irq, reg, shift, wrk;
275 	enum intr_trigger trig;
276 	enum intr_polarity pol;
277 
278 	sc = device_get_softc(dev);
279 	gi = (struct gpio_irqsrc *)isrc;
280 
281 	/* Get config for interrupt. */
282 	if (data == NULL || data->type != INTR_MAP_DATA_FDT)
283 		return (ENOTSUP);
284 	daf = (struct intr_map_data_fdt *)data;
285 	error = gpio_pic_map_fdt(dev, daf->ncells, daf->cells, &irq, &pol,
286 	    &trig);
287 	if (error != 0)
288 		return (error);
289 	if (gi->gi_irq != irq)
290 		return (EINVAL);
291 
292 	/* Compare config if this is not first setup. */
293 	if (isrc->isrc_handlers != 0) {
294 		if (pol != gi->gi_pol || trig != gi->gi_trig)
295 			return (EINVAL);
296 		else
297 			return (0);
298 	}
299 
300 	gi->gi_pol = pol;
301 	gi->gi_trig = trig;
302 
303 	if (trig == INTR_TRIGGER_LEVEL) {
304 		if (pol == INTR_POLARITY_LOW)
305 			icfg = GPIO_ICR_COND_LOW;
306 		else
307 			icfg = GPIO_ICR_COND_HIGH;
308 	} else {
309 		if (pol == INTR_POLARITY_HIGH)
310 			icfg = GPIO_ICR_COND_FALL;
311 		else
312 			icfg = GPIO_ICR_COND_RISE;
313 	}
314 
315 	if (irq < 16) {
316 		reg = IMX_GPIO_ICR1_REG;
317 		shift = 2 * irq;
318 	} else {
319 		reg = IMX_GPIO_ICR2_REG;
320 		shift = 2 * (irq - 16);
321 	}
322 
323 	mtx_lock_spin(&sc->sc_mtx);
324 	CLEAR4(sc, IMX_GPIO_IMR_REG, (1U << irq));
325 	WRITE4(sc, IMX_GPIO_ISR_REG, (1U << irq));
326 	wrk = READ4(sc, reg);
327 	wrk &= ~(0x03 << shift);
328 	wrk |= icfg << shift;
329 	WRITE4(sc, reg, wrk);
330 	mtx_unlock_spin(&sc->sc_mtx);
331 	return (0);
332 }
333 
334 /*
335  * this is mask_intr
336  */
337 static void
338 gpio_pic_disable_intr(device_t dev, struct intr_irqsrc *isrc)
339 {
340 	struct imx51_gpio_softc *sc;
341 	u_int irq;
342 
343 	sc = device_get_softc(dev);
344 	irq = ((struct gpio_irqsrc *)isrc)->gi_irq;
345 
346 	mtx_lock_spin(&sc->sc_mtx);
347 	CLEAR4(sc, IMX_GPIO_IMR_REG, (1U << irq));
348 	mtx_unlock_spin(&sc->sc_mtx);
349 }
350 
351 /*
352  * this is unmask_intr
353  */
354 static void
355 gpio_pic_enable_intr(device_t dev, struct intr_irqsrc *isrc)
356 {
357 	struct imx51_gpio_softc *sc;
358 	u_int irq;
359 
360 	sc = device_get_softc(dev);
361 	irq = ((struct gpio_irqsrc *)isrc)->gi_irq;
362 
363 	mtx_lock_spin(&sc->sc_mtx);
364 	SET4(sc, IMX_GPIO_IMR_REG, (1U << irq));
365 	mtx_unlock_spin(&sc->sc_mtx);
366 }
367 
368 static void
369 gpio_pic_post_filter(device_t dev, struct intr_irqsrc *isrc)
370 {
371 	struct imx51_gpio_softc *sc;
372 	u_int irq;
373 
374 	sc = device_get_softc(dev);
375 	irq = ((struct gpio_irqsrc *)isrc)->gi_irq;
376 
377 	arm_irq_memory_barrier(0);
378         /* EOI.  W1C reg so no r-m-w, no locking needed. */
379 	WRITE4(sc, IMX_GPIO_ISR_REG, (1U << irq));
380 }
381 
382 static void
383 gpio_pic_post_ithread(device_t dev, struct intr_irqsrc *isrc)
384 {
385 
386 	arm_irq_memory_barrier(0);
387 	gpio_pic_enable_intr(dev, isrc);
388 }
389 
390 static void
391 gpio_pic_pre_ithread(device_t dev, struct intr_irqsrc *isrc)
392 {
393 
394 	gpio_pic_disable_intr(dev, isrc);
395 }
396 
397 static int
398 gpio_pic_filter(void *arg)
399 {
400 	struct imx51_gpio_softc *sc;
401 	struct intr_irqsrc *isrc;
402 	uint32_t i, interrupts;
403 
404 	sc = arg;
405 	mtx_lock_spin(&sc->sc_mtx);
406 	interrupts = READ4(sc, IMX_GPIO_ISR_REG) & READ4(sc, IMX_GPIO_IMR_REG);
407 	mtx_unlock_spin(&sc->sc_mtx);
408 
409 	for (i = 0; interrupts != 0; i++, interrupts >>= 1) {
410 		if ((interrupts & 0x1) == 0)
411 			continue;
412 		isrc = &sc->gpio_pic_irqsrc[i].gi_isrc;
413 		if (intr_isrc_dispatch(isrc, curthread->td_intr_frame) != 0) {
414 			gpio_pic_disable_intr(sc->dev, isrc);
415 			gpio_pic_post_filter(sc->dev, isrc);
416 			device_printf(sc->dev, "Stray irq %u disabled\n", i);
417 		}
418 	}
419 
420 	return (FILTER_HANDLED);
421 }
422 
423 /*
424  * Initialize our isrcs and register them with intrng.
425  */
426 static int
427 gpio_pic_register_isrcs(struct imx51_gpio_softc *sc)
428 {
429 	int error;
430 	uint32_t irq;
431 	const char *name;
432 
433 	name = device_get_nameunit(sc->dev);
434 	for (irq = 0; irq < NGPIO; irq++) {
435 		sc->gpio_pic_irqsrc[irq].gi_irq = irq;
436 		sc->gpio_pic_irqsrc[irq].gi_pol = INTR_POLARITY_CONFORM;
437 		sc->gpio_pic_irqsrc[irq].gi_trig = INTR_TRIGGER_CONFORM;
438 
439 		error = intr_isrc_register(&sc->gpio_pic_irqsrc[irq].gi_isrc,
440 		    sc->dev, 0, "%s,%u", name, irq);
441 		if (error != 0) {
442 			/* XXX call intr_isrc_deregister() */
443 			device_printf(sc->dev, "%s failed", __func__);
444 			return (error);
445 		}
446 	}
447 	return (0);
448 }
449 #endif
450 
451 /*
452  *
453  */
454 static void
455 imx51_gpio_pin_configure(struct imx51_gpio_softc *sc, struct gpio_pin *pin,
456     unsigned int flags)
457 {
458 	u_int newflags;
459 
460 	mtx_lock_spin(&sc->sc_mtx);
461 
462 	/*
463 	 * Manage input/output; other flags not supported yet.
464 	 *
465 	 * Note that changes to pin->gp_flags must be acccumulated in newflags
466 	 * and stored with a single writeback to gp_flags at the end, to enable
467 	 * unlocked reads of that value elsewhere.
468 	 */
469 	if (flags & (GPIO_PIN_INPUT | GPIO_PIN_OUTPUT)) {
470 		newflags = pin->gp_flags & ~(GPIO_PIN_INPUT | GPIO_PIN_OUTPUT);
471 		if (flags & GPIO_PIN_OUTPUT) {
472 			newflags |= GPIO_PIN_OUTPUT;
473 			SET4(sc, IMX_GPIO_OE_REG, (1U << pin->gp_pin));
474 		} else {
475 			newflags |= GPIO_PIN_INPUT;
476 			CLEAR4(sc, IMX_GPIO_OE_REG, (1U << pin->gp_pin));
477 		}
478 		pin->gp_flags = newflags;
479 	}
480 
481 	mtx_unlock_spin(&sc->sc_mtx);
482 }
483 
484 static device_t
485 imx51_gpio_get_bus(device_t dev)
486 {
487 	struct imx51_gpio_softc *sc;
488 
489 	sc = device_get_softc(dev);
490 
491 	return (sc->sc_busdev);
492 }
493 
494 static int
495 imx51_gpio_pin_max(device_t dev, int *maxpin)
496 {
497 	struct imx51_gpio_softc *sc;
498 
499 	sc = device_get_softc(dev);
500 	*maxpin = sc->gpio_npins - 1;
501 
502 	return (0);
503 }
504 
505 static int
506 imx51_gpio_pin_getcaps(device_t dev, uint32_t pin, uint32_t *caps)
507 {
508 	struct imx51_gpio_softc *sc;
509 
510 	sc = device_get_softc(dev);
511 
512 	if (pin >= sc->gpio_npins)
513 		return (EINVAL);
514 
515 	*caps = sc->gpio_pins[pin].gp_caps;
516 
517 	return (0);
518 }
519 
520 static int
521 imx51_gpio_pin_getflags(device_t dev, uint32_t pin, uint32_t *flags)
522 {
523 	struct imx51_gpio_softc *sc;
524 
525 	sc = device_get_softc(dev);
526 
527 	if (pin >= sc->gpio_npins)
528 		return (EINVAL);
529 
530 	*flags = sc->gpio_pins[pin].gp_flags;
531 
532 	return (0);
533 }
534 
535 static int
536 imx51_gpio_pin_getname(device_t dev, uint32_t pin, char *name)
537 {
538 	struct imx51_gpio_softc *sc;
539 
540 	sc = device_get_softc(dev);
541 	if (pin >= sc->gpio_npins)
542 		return (EINVAL);
543 
544 	mtx_lock_spin(&sc->sc_mtx);
545 	memcpy(name, sc->gpio_pins[pin].gp_name, GPIOMAXNAME);
546 	mtx_unlock_spin(&sc->sc_mtx);
547 
548 	return (0);
549 }
550 
551 static int
552 imx51_gpio_pin_setflags(device_t dev, uint32_t pin, uint32_t flags)
553 {
554 	struct imx51_gpio_softc *sc;
555 
556 	sc = device_get_softc(dev);
557 
558 	if (pin >= sc->gpio_npins)
559 		return (EINVAL);
560 
561 	imx51_gpio_pin_configure(sc, &sc->gpio_pins[pin], flags);
562 
563 	return (0);
564 }
565 
566 static int
567 imx51_gpio_pin_set(device_t dev, uint32_t pin, unsigned int value)
568 {
569 	struct imx51_gpio_softc *sc;
570 
571 	sc = device_get_softc(dev);
572 
573 	if (pin >= sc->gpio_npins)
574 		return (EINVAL);
575 
576 	mtx_lock_spin(&sc->sc_mtx);
577 	if (value)
578 		SET4(sc, IMX_GPIO_DR_REG, (1U << pin));
579 	else
580 		CLEAR4(sc, IMX_GPIO_DR_REG, (1U << pin));
581 	mtx_unlock_spin(&sc->sc_mtx);
582 
583 	return (0);
584 }
585 
586 static int
587 imx51_gpio_pin_get(device_t dev, uint32_t pin, unsigned int *val)
588 {
589 	struct imx51_gpio_softc *sc;
590 
591 	sc = device_get_softc(dev);
592 
593 	if (pin >= sc->gpio_npins)
594 		return (EINVAL);
595 
596 	*val = (READ4(sc, IMX_GPIO_DR_REG) >> pin) & 1;
597 
598 	return (0);
599 }
600 
601 static int
602 imx51_gpio_pin_toggle(device_t dev, uint32_t pin)
603 {
604 	struct imx51_gpio_softc *sc;
605 
606 	sc = device_get_softc(dev);
607 
608 	if (pin >= sc->gpio_npins)
609 		return (EINVAL);
610 
611 	mtx_lock_spin(&sc->sc_mtx);
612 	WRITE4(sc, IMX_GPIO_DR_REG,
613 	    (READ4(sc, IMX_GPIO_DR_REG) ^ (1U << pin)));
614 	mtx_unlock_spin(&sc->sc_mtx);
615 
616 	return (0);
617 }
618 
619 static int
620 imx51_gpio_probe(device_t dev)
621 {
622 
623 	if (!ofw_bus_status_okay(dev))
624 		return (ENXIO);
625 
626 	if (ofw_bus_search_compatible(dev, compat_data)->ocd_data != 0) {
627 		device_set_desc(dev, "Freescale i.MX GPIO Controller");
628 		return (BUS_PROBE_DEFAULT);
629 	}
630 
631 	return (ENXIO);
632 }
633 
634 static int
635 imx51_gpio_attach(device_t dev)
636 {
637 	struct imx51_gpio_softc *sc;
638 	int i, irq, unit;
639 
640 	sc = device_get_softc(dev);
641 	sc->dev = dev;
642 	sc->gpio_npins = NGPIO;
643 
644 	mtx_init(&sc->sc_mtx, device_get_nameunit(sc->dev), NULL, MTX_SPIN);
645 
646 	if (bus_alloc_resources(dev, imx_gpio_spec, sc->sc_res)) {
647 		device_printf(dev, "could not allocate resources\n");
648 		bus_release_resources(dev, imx_gpio_spec, sc->sc_res);
649 		mtx_destroy(&sc->sc_mtx);
650 		return (ENXIO);
651 	}
652 
653 	sc->sc_iot = rman_get_bustag(sc->sc_res[0]);
654 	sc->sc_ioh = rman_get_bushandle(sc->sc_res[0]);
655 	/*
656 	 * Mask off all interrupts in hardware, then set up interrupt handling.
657 	 */
658 	WRITE4(sc, IMX_GPIO_IMR_REG, 0);
659 	for (irq = 0; irq < 2; irq++) {
660 #ifdef INTRNG
661 		if ((bus_setup_intr(dev, sc->sc_res[1 + irq], INTR_TYPE_CLK,
662 		    gpio_pic_filter, NULL, sc, &sc->gpio_ih[irq]))) {
663 			device_printf(dev,
664 			    "WARNING: unable to register interrupt handler\n");
665 			imx51_gpio_detach(dev);
666 			return (ENXIO);
667 		}
668 #endif
669 	}
670 
671 	unit = device_get_unit(dev);
672 	for (i = 0; i < sc->gpio_npins; i++) {
673  		sc->gpio_pins[i].gp_pin = i;
674  		sc->gpio_pins[i].gp_caps = DEFAULT_CAPS;
675  		sc->gpio_pins[i].gp_flags =
676  		    (READ4(sc, IMX_GPIO_OE_REG) & (1U << i)) ? GPIO_PIN_OUTPUT :
677  		    GPIO_PIN_INPUT;
678  		snprintf(sc->gpio_pins[i].gp_name, GPIOMAXNAME,
679  		    "imx_gpio%d.%d", unit, i);
680 	}
681 
682 #ifdef INTRNG
683 	gpio_pic_register_isrcs(sc);
684 	intr_pic_register(dev, OF_xref_from_node(ofw_bus_get_node(dev)));
685 #endif
686 	sc->sc_busdev = gpiobus_attach_bus(dev);
687 
688 	if (sc->sc_busdev == NULL) {
689 		imx51_gpio_detach(dev);
690 		return (ENXIO);
691 	}
692 
693 	return (0);
694 }
695 
696 static int
697 imx51_gpio_detach(device_t dev)
698 {
699 	int irq;
700 	struct imx51_gpio_softc *sc;
701 
702 	sc = device_get_softc(dev);
703 
704 	gpiobus_detach_bus(dev);
705 	for (irq = 1; irq <= 2; irq++) {
706 		if (sc->gpio_ih[irq])
707 			bus_teardown_intr(dev, sc->sc_res[irq], sc->gpio_ih[irq]);
708 	}
709 	bus_release_resources(dev, imx_gpio_spec, sc->sc_res);
710 	mtx_destroy(&sc->sc_mtx);
711 
712 	return(0);
713 }
714 
715 static device_method_t imx51_gpio_methods[] = {
716 	DEVMETHOD(device_probe,		imx51_gpio_probe),
717 	DEVMETHOD(device_attach,	imx51_gpio_attach),
718 	DEVMETHOD(device_detach,	imx51_gpio_detach),
719 
720 #ifdef INTRNG
721 	/* Interrupt controller interface */
722 	DEVMETHOD(pic_disable_intr,	gpio_pic_disable_intr),
723 	DEVMETHOD(pic_enable_intr,	gpio_pic_enable_intr),
724 	DEVMETHOD(pic_map_intr,		gpio_pic_map_intr),
725 	DEVMETHOD(pic_setup_intr,	gpio_pic_setup_intr),
726 	DEVMETHOD(pic_teardown_intr,	gpio_pic_teardown_intr),
727 	DEVMETHOD(pic_post_filter,	gpio_pic_post_filter),
728 	DEVMETHOD(pic_post_ithread,	gpio_pic_post_ithread),
729 	DEVMETHOD(pic_pre_ithread,	gpio_pic_pre_ithread),
730 #endif
731 
732 	/* GPIO protocol */
733 	DEVMETHOD(gpio_get_bus,		imx51_gpio_get_bus),
734 	DEVMETHOD(gpio_pin_max,		imx51_gpio_pin_max),
735 	DEVMETHOD(gpio_pin_getname,	imx51_gpio_pin_getname),
736 	DEVMETHOD(gpio_pin_getflags,	imx51_gpio_pin_getflags),
737 	DEVMETHOD(gpio_pin_getcaps,	imx51_gpio_pin_getcaps),
738 	DEVMETHOD(gpio_pin_setflags,	imx51_gpio_pin_setflags),
739 	DEVMETHOD(gpio_pin_get,		imx51_gpio_pin_get),
740 	DEVMETHOD(gpio_pin_set,		imx51_gpio_pin_set),
741 	DEVMETHOD(gpio_pin_toggle,	imx51_gpio_pin_toggle),
742 	{0, 0},
743 };
744 
745 static driver_t imx51_gpio_driver = {
746 	"gpio",
747 	imx51_gpio_methods,
748 	sizeof(struct imx51_gpio_softc),
749 };
750 static devclass_t imx51_gpio_devclass;
751 
752 DRIVER_MODULE(imx51_gpio, simplebus, imx51_gpio_driver, imx51_gpio_devclass,
753     0, 0);
754