xref: /freebsd/sys/arm/freescale/imx/imx_gpio.c (revision 3fc36ee018bb836bd1796067cf4ef8683f166ebc)
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		GPIO_ICR_COND_MASK	0x3
88 #define	IMX_GPIO_IMR_REG	0x014 /* Interrupt Mask Register */
89 #define	IMX_GPIO_ISR_REG	0x018 /* Interrupt Status Register */
90 #define	IMX_GPIO_EDGE_REG	0x01C /* Edge Detect Register */
91 
92 #ifdef INTRNG
93 #define	DEFAULT_CAPS	(GPIO_PIN_INPUT | GPIO_PIN_OUTPUT | \
94     GPIO_INTR_LEVEL_LOW | GPIO_INTR_LEVEL_HIGH | GPIO_INTR_EDGE_RISING | \
95     GPIO_INTR_EDGE_FALLING | GPIO_INTR_EDGE_BOTH)
96 #else
97 #define	DEFAULT_CAPS	(GPIO_PIN_INPUT | GPIO_PIN_OUTPUT)
98 #endif
99 
100 #define	NGPIO		32
101 
102 #ifdef INTRNG
103 struct gpio_irqsrc {
104 	struct intr_irqsrc	gi_isrc;
105 	u_int			gi_irq;
106 	uint32_t		gi_mode;
107 };
108 #endif
109 
110 struct imx51_gpio_softc {
111 	device_t		dev;
112 	device_t		sc_busdev;
113 	struct mtx		sc_mtx;
114 	struct resource		*sc_res[3]; /* 1 x mem, 2 x IRQ */
115 	void			*gpio_ih[2];
116 	bus_space_tag_t		sc_iot;
117 	bus_space_handle_t	sc_ioh;
118 	int			gpio_npins;
119 	struct gpio_pin		gpio_pins[NGPIO];
120 #ifdef INTRNG
121 	struct gpio_irqsrc 	gpio_pic_irqsrc[NGPIO];
122 #endif
123 };
124 
125 static struct ofw_compat_data compat_data[] = {
126 	{"fsl,imx6q-gpio",  1},
127 	{"fsl,imx53-gpio",  1},
128 	{"fsl,imx51-gpio",  1},
129 	{NULL,	            0}
130 };
131 
132 static struct resource_spec imx_gpio_spec[] = {
133 	{ SYS_RES_MEMORY,	0,	RF_ACTIVE },
134 	{ SYS_RES_IRQ,		0,	RF_ACTIVE },
135 	{ SYS_RES_IRQ,		1,	RF_ACTIVE },
136 	{ -1, 0 }
137 };
138 
139 /*
140  * Helpers
141  */
142 static void imx51_gpio_pin_configure(struct imx51_gpio_softc *,
143     struct gpio_pin *, uint32_t);
144 
145 /*
146  * Driver stuff
147  */
148 static int imx51_gpio_probe(device_t);
149 static int imx51_gpio_attach(device_t);
150 static int imx51_gpio_detach(device_t);
151 
152 /*
153  * GPIO interface
154  */
155 static device_t imx51_gpio_get_bus(device_t);
156 static int imx51_gpio_pin_max(device_t, int *);
157 static int imx51_gpio_pin_getcaps(device_t, uint32_t, uint32_t *);
158 static int imx51_gpio_pin_getflags(device_t, uint32_t, uint32_t *);
159 static int imx51_gpio_pin_getname(device_t, uint32_t, char *);
160 static int imx51_gpio_pin_setflags(device_t, uint32_t, uint32_t);
161 static int imx51_gpio_pin_set(device_t, uint32_t, unsigned int);
162 static int imx51_gpio_pin_get(device_t, uint32_t, unsigned int *);
163 static int imx51_gpio_pin_toggle(device_t, uint32_t pin);
164 
165 #ifdef INTRNG
166 static int
167 gpio_pic_map_fdt(struct imx51_gpio_softc *sc, struct intr_map_data_fdt *daf,
168     u_int *irqp, uint32_t *modep)
169 {
170 	u_int irq;
171 	uint32_t mode;
172 
173 	/*
174 	 * From devicetree/bindings/gpio/fsl-imx-gpio.txt:
175 	 *  #interrupt-cells:  2. The first cell is the GPIO number. The second
176 	 *  cell bits[3:0] is used to specify trigger type and level flags:
177 	 *    1 = low-to-high edge triggered.
178 	 *    2 = high-to-low edge triggered.
179 	 *    4 = active high level-sensitive.
180 	 *    8 = active low level-sensitive.
181 	 * We can do any single one of these modes, and also edge low+high
182 	 * (i.e., trigger on both edges); other combinations are not supported.
183 	 */
184 
185 	if (daf->ncells != 2) {
186 		device_printf(sc->dev, "Invalid #interrupt-cells\n");
187 		return (EINVAL);
188 	}
189 
190 	irq = daf->cells[0];
191 	if (irq >= sc->gpio_npins) {
192 		device_printf(sc->dev, "Invalid interrupt number %u\n", irq);
193 		return (EINVAL);
194 	}
195 	switch (daf->cells[1]) {
196 	case 1:
197 		mode = GPIO_INTR_EDGE_RISING;
198 		break;
199 	case 2:
200 		mode = GPIO_INTR_EDGE_FALLING;
201 		break;
202 	case 3:
203 		mode = GPIO_INTR_EDGE_BOTH;
204 		break;
205 	case 4:
206 		mode = GPIO_INTR_LEVEL_HIGH;
207 		break;
208 	case 8:
209 		mode = GPIO_INTR_LEVEL_LOW;
210 		break;
211 	default:
212 		device_printf(sc->dev, "Unsupported interrupt mode 0x%2x\n",
213 		    daf->cells[1]);
214 		return (ENOTSUP);
215 	}
216 	*irqp = irq;
217 	if (modep != NULL)
218 		*modep = mode;
219 	return (0);
220 }
221 
222 static int
223 gpio_pic_map_gpio(struct imx51_gpio_softc *sc, struct intr_map_data_gpio *dag,
224     u_int *irqp, uint32_t *modep)
225 {
226 	u_int irq;
227 
228 	irq = dag->gpio_pin_num;
229 	if (irq >= sc->gpio_npins) {
230 		device_printf(sc->dev, "Invalid interrupt number %u\n", irq);
231 		return (EINVAL);
232 	}
233 
234 	switch (dag->gpio_intr_mode) {
235 	case GPIO_INTR_LEVEL_LOW:
236 	case GPIO_INTR_LEVEL_HIGH:
237 	case GPIO_INTR_EDGE_RISING:
238 	case GPIO_INTR_EDGE_FALLING:
239 	case GPIO_INTR_EDGE_BOTH:
240 		break;
241 	default:
242 		device_printf(sc->dev, "Unsupported interrupt mode 0x%8x\n",
243 		    dag->gpio_intr_mode);
244 		return (EINVAL);
245 	}
246 
247 	*irqp = irq;
248 	if (modep != NULL)
249 		*modep = dag->gpio_intr_mode;
250 	return (0);
251 }
252 
253 static int
254 gpio_pic_map(struct imx51_gpio_softc *sc, struct intr_map_data *data,
255     u_int *irqp, uint32_t *modep)
256 {
257 
258 	switch (data->type) {
259 	case INTR_MAP_DATA_FDT:
260 		return (gpio_pic_map_fdt(sc, (struct intr_map_data_fdt *)data,
261 		    irqp, modep));
262 	case INTR_MAP_DATA_GPIO:
263 		return (gpio_pic_map_gpio(sc, (struct intr_map_data_gpio *)data,
264 		    irqp, modep));
265 	default:
266 		return (ENOTSUP);
267 	}
268 }
269 
270 static int
271 gpio_pic_map_intr(device_t dev, struct intr_map_data *data,
272     struct intr_irqsrc **isrcp)
273 {
274 	int error;
275 	u_int irq;
276 	struct imx51_gpio_softc *sc;
277 
278 	sc = device_get_softc(dev);
279 	error = gpio_pic_map(sc, data, &irq, NULL);
280 	if (error == 0)
281 		*isrcp = &sc->gpio_pic_irqsrc[irq].gi_isrc;
282 	return (error);
283 }
284 
285 static int
286 gpio_pic_teardown_intr(device_t dev, struct intr_irqsrc *isrc,
287     struct resource *res, struct intr_map_data *data)
288 {
289 	struct imx51_gpio_softc *sc;
290 	struct gpio_irqsrc *gi;
291 
292 	sc = device_get_softc(dev);
293 	if (isrc->isrc_handlers == 0) {
294 		gi = (struct gpio_irqsrc *)isrc;
295 		gi->gi_mode = GPIO_INTR_CONFORM;
296 
297 		// XXX Not sure this is necessary
298 		mtx_lock_spin(&sc->sc_mtx);
299 		CLEAR4(sc, IMX_GPIO_IMR_REG, (1U << gi->gi_irq));
300 		WRITE4(sc, IMX_GPIO_ISR_REG, (1U << gi->gi_irq));
301 		mtx_unlock_spin(&sc->sc_mtx);
302 	}
303 	return (0);
304 }
305 
306 static int
307 gpio_pic_setup_intr(device_t dev, struct intr_irqsrc *isrc,
308     struct resource *res, struct intr_map_data *data)
309 {
310 	struct imx51_gpio_softc *sc;
311 	struct gpio_irqsrc *gi;
312 	int error;
313 	u_int icfg, irq, reg, shift, wrk;
314 	uint32_t mode;
315 
316 	if (data == NULL)
317 		return (ENOTSUP);
318 
319 	sc = device_get_softc(dev);
320 	gi = (struct gpio_irqsrc *)isrc;
321 
322 	/* Get config for interrupt. */
323 	error = gpio_pic_map(sc, data, &irq, &mode);
324 	if (error != 0)
325 		return (error);
326 	if (gi->gi_irq != irq)
327 		return (EINVAL);
328 
329 	/* Compare config if this is not first setup. */
330 	if (isrc->isrc_handlers != 0)
331 		return (gi->gi_mode == mode ? 0 : EINVAL);
332 	gi->gi_mode = mode;
333 
334 	/*
335 	 * To interrupt on both edges we have to use the EDGE register.  The
336 	 * manual says it only exists for backwards compatibilty with older imx
337 	 * chips, but it's also the only way to configure interrupting on both
338 	 * edges.  If the EDGE bit is on, the corresponding ICRn bit is ignored.
339 	 */
340 	mtx_lock_spin(&sc->sc_mtx);
341 	if (mode == GPIO_INTR_EDGE_BOTH) {
342 		SET4(sc, IMX_GPIO_EDGE_REG, (1u << irq));
343 	} else {
344 		CLEAR4(sc, IMX_GPIO_EDGE_REG, (1u << irq));
345 		switch (mode) {
346 		default:
347 			/* silence warnings; default can't actually happen. */
348 			/* FALLTHROUGH */
349 		case GPIO_INTR_LEVEL_LOW:
350 			icfg = GPIO_ICR_COND_LOW;
351 			break;
352 		case GPIO_INTR_LEVEL_HIGH:
353 			icfg = GPIO_ICR_COND_HIGH;
354 			break;
355 		case GPIO_INTR_EDGE_RISING:
356 			icfg = GPIO_ICR_COND_RISE;
357 			break;
358 		case GPIO_INTR_EDGE_FALLING:
359 			icfg = GPIO_ICR_COND_FALL;
360 			break;
361 		}
362 		if (irq < 16) {
363 			reg = IMX_GPIO_ICR1_REG;
364 			shift = 2 * irq;
365 		} else {
366 			reg = IMX_GPIO_ICR2_REG;
367 			shift = 2 * (irq - 16);
368 		}
369 		wrk = READ4(sc, reg);
370 		wrk &= ~(GPIO_ICR_COND_MASK << shift);
371 		wrk |= icfg << shift;
372 		WRITE4(sc, reg, wrk);
373 	}
374 	WRITE4(sc, IMX_GPIO_ISR_REG, (1u << irq));
375 	SET4(sc, IMX_GPIO_IMR_REG, (1u << irq));
376 	mtx_unlock_spin(&sc->sc_mtx);
377 
378 	return (0);
379 }
380 
381 /*
382  * this is mask_intr
383  */
384 static void
385 gpio_pic_disable_intr(device_t dev, struct intr_irqsrc *isrc)
386 {
387 	struct imx51_gpio_softc *sc;
388 	u_int irq;
389 
390 	sc = device_get_softc(dev);
391 	irq = ((struct gpio_irqsrc *)isrc)->gi_irq;
392 
393 	mtx_lock_spin(&sc->sc_mtx);
394 	CLEAR4(sc, IMX_GPIO_IMR_REG, (1U << irq));
395 	mtx_unlock_spin(&sc->sc_mtx);
396 }
397 
398 /*
399  * this is unmask_intr
400  */
401 static void
402 gpio_pic_enable_intr(device_t dev, struct intr_irqsrc *isrc)
403 {
404 	struct imx51_gpio_softc *sc;
405 	u_int irq;
406 
407 	sc = device_get_softc(dev);
408 	irq = ((struct gpio_irqsrc *)isrc)->gi_irq;
409 
410 	mtx_lock_spin(&sc->sc_mtx);
411 	SET4(sc, IMX_GPIO_IMR_REG, (1U << irq));
412 	mtx_unlock_spin(&sc->sc_mtx);
413 }
414 
415 static void
416 gpio_pic_post_filter(device_t dev, struct intr_irqsrc *isrc)
417 {
418 	struct imx51_gpio_softc *sc;
419 	u_int irq;
420 
421 	sc = device_get_softc(dev);
422 	irq = ((struct gpio_irqsrc *)isrc)->gi_irq;
423 
424 	arm_irq_memory_barrier(0);
425         /* EOI.  W1C reg so no r-m-w, no locking needed. */
426 	WRITE4(sc, IMX_GPIO_ISR_REG, (1U << irq));
427 }
428 
429 static void
430 gpio_pic_post_ithread(device_t dev, struct intr_irqsrc *isrc)
431 {
432 	struct imx51_gpio_softc *sc;
433 	u_int irq;
434 
435 	sc = device_get_softc(dev);
436 	irq = ((struct gpio_irqsrc *)isrc)->gi_irq;
437 
438 	arm_irq_memory_barrier(0);
439 	/* EOI.  W1C reg so no r-m-w, no locking needed. */
440 	WRITE4(sc, IMX_GPIO_ISR_REG, (1U << irq));
441 	gpio_pic_enable_intr(dev, isrc);
442 }
443 
444 static void
445 gpio_pic_pre_ithread(device_t dev, struct intr_irqsrc *isrc)
446 {
447 	gpio_pic_disable_intr(dev, isrc);
448 }
449 
450 static int
451 gpio_pic_filter(void *arg)
452 {
453 	struct imx51_gpio_softc *sc;
454 	struct intr_irqsrc *isrc;
455 	uint32_t i, interrupts;
456 
457 	sc = arg;
458 	mtx_lock_spin(&sc->sc_mtx);
459 	interrupts = READ4(sc, IMX_GPIO_ISR_REG) & READ4(sc, IMX_GPIO_IMR_REG);
460 	mtx_unlock_spin(&sc->sc_mtx);
461 
462 	for (i = 0; interrupts != 0; i++, interrupts >>= 1) {
463 		if ((interrupts & 0x1) == 0)
464 			continue;
465 		isrc = &sc->gpio_pic_irqsrc[i].gi_isrc;
466 		if (intr_isrc_dispatch(isrc, curthread->td_intr_frame) != 0) {
467 			gpio_pic_disable_intr(sc->dev, isrc);
468 			gpio_pic_post_filter(sc->dev, isrc);
469 			device_printf(sc->dev, "Stray irq %u disabled\n", i);
470 		}
471 	}
472 
473 	return (FILTER_HANDLED);
474 }
475 
476 /*
477  * Initialize our isrcs and register them with intrng.
478  */
479 static int
480 gpio_pic_register_isrcs(struct imx51_gpio_softc *sc)
481 {
482 	int error;
483 	uint32_t irq;
484 	const char *name;
485 
486 	name = device_get_nameunit(sc->dev);
487 	for (irq = 0; irq < NGPIO; irq++) {
488 		sc->gpio_pic_irqsrc[irq].gi_irq = irq;
489 		sc->gpio_pic_irqsrc[irq].gi_mode = GPIO_INTR_CONFORM;
490 
491 		error = intr_isrc_register(&sc->gpio_pic_irqsrc[irq].gi_isrc,
492 		    sc->dev, 0, "%s,%u", name, irq);
493 		if (error != 0) {
494 			/* XXX call intr_isrc_deregister() */
495 			device_printf(sc->dev, "%s failed", __func__);
496 			return (error);
497 		}
498 	}
499 	return (0);
500 }
501 #endif
502 
503 /*
504  *
505  */
506 static void
507 imx51_gpio_pin_configure(struct imx51_gpio_softc *sc, struct gpio_pin *pin,
508     unsigned int flags)
509 {
510 	u_int newflags;
511 
512 	mtx_lock_spin(&sc->sc_mtx);
513 
514 	/*
515 	 * Manage input/output; other flags not supported yet.
516 	 *
517 	 * Note that changes to pin->gp_flags must be acccumulated in newflags
518 	 * and stored with a single writeback to gp_flags at the end, to enable
519 	 * unlocked reads of that value elsewhere.
520 	 */
521 	if (flags & (GPIO_PIN_INPUT | GPIO_PIN_OUTPUT)) {
522 		newflags = pin->gp_flags & ~(GPIO_PIN_INPUT | GPIO_PIN_OUTPUT);
523 		if (flags & GPIO_PIN_OUTPUT) {
524 			newflags |= GPIO_PIN_OUTPUT;
525 			SET4(sc, IMX_GPIO_OE_REG, (1U << pin->gp_pin));
526 		} else {
527 			newflags |= GPIO_PIN_INPUT;
528 			CLEAR4(sc, IMX_GPIO_OE_REG, (1U << pin->gp_pin));
529 		}
530 		pin->gp_flags = newflags;
531 	}
532 
533 	mtx_unlock_spin(&sc->sc_mtx);
534 }
535 
536 static device_t
537 imx51_gpio_get_bus(device_t dev)
538 {
539 	struct imx51_gpio_softc *sc;
540 
541 	sc = device_get_softc(dev);
542 
543 	return (sc->sc_busdev);
544 }
545 
546 static int
547 imx51_gpio_pin_max(device_t dev, int *maxpin)
548 {
549 	struct imx51_gpio_softc *sc;
550 
551 	sc = device_get_softc(dev);
552 	*maxpin = sc->gpio_npins - 1;
553 
554 	return (0);
555 }
556 
557 static int
558 imx51_gpio_pin_getcaps(device_t dev, uint32_t pin, uint32_t *caps)
559 {
560 	struct imx51_gpio_softc *sc;
561 
562 	sc = device_get_softc(dev);
563 
564 	if (pin >= sc->gpio_npins)
565 		return (EINVAL);
566 
567 	*caps = sc->gpio_pins[pin].gp_caps;
568 
569 	return (0);
570 }
571 
572 static int
573 imx51_gpio_pin_getflags(device_t dev, uint32_t pin, uint32_t *flags)
574 {
575 	struct imx51_gpio_softc *sc;
576 
577 	sc = device_get_softc(dev);
578 
579 	if (pin >= sc->gpio_npins)
580 		return (EINVAL);
581 
582 	*flags = sc->gpio_pins[pin].gp_flags;
583 
584 	return (0);
585 }
586 
587 static int
588 imx51_gpio_pin_getname(device_t dev, uint32_t pin, char *name)
589 {
590 	struct imx51_gpio_softc *sc;
591 
592 	sc = device_get_softc(dev);
593 	if (pin >= sc->gpio_npins)
594 		return (EINVAL);
595 
596 	mtx_lock_spin(&sc->sc_mtx);
597 	memcpy(name, sc->gpio_pins[pin].gp_name, GPIOMAXNAME);
598 	mtx_unlock_spin(&sc->sc_mtx);
599 
600 	return (0);
601 }
602 
603 static int
604 imx51_gpio_pin_setflags(device_t dev, uint32_t pin, uint32_t flags)
605 {
606 	struct imx51_gpio_softc *sc;
607 
608 	sc = device_get_softc(dev);
609 
610 	if (pin >= sc->gpio_npins)
611 		return (EINVAL);
612 
613 	imx51_gpio_pin_configure(sc, &sc->gpio_pins[pin], flags);
614 
615 	return (0);
616 }
617 
618 static int
619 imx51_gpio_pin_set(device_t dev, uint32_t pin, unsigned int value)
620 {
621 	struct imx51_gpio_softc *sc;
622 
623 	sc = device_get_softc(dev);
624 
625 	if (pin >= sc->gpio_npins)
626 		return (EINVAL);
627 
628 	mtx_lock_spin(&sc->sc_mtx);
629 	if (value)
630 		SET4(sc, IMX_GPIO_DR_REG, (1U << pin));
631 	else
632 		CLEAR4(sc, IMX_GPIO_DR_REG, (1U << pin));
633 	mtx_unlock_spin(&sc->sc_mtx);
634 
635 	return (0);
636 }
637 
638 static int
639 imx51_gpio_pin_get(device_t dev, uint32_t pin, unsigned int *val)
640 {
641 	struct imx51_gpio_softc *sc;
642 
643 	sc = device_get_softc(dev);
644 
645 	if (pin >= sc->gpio_npins)
646 		return (EINVAL);
647 
648 	*val = (READ4(sc, IMX_GPIO_DR_REG) >> pin) & 1;
649 
650 	return (0);
651 }
652 
653 static int
654 imx51_gpio_pin_toggle(device_t dev, uint32_t pin)
655 {
656 	struct imx51_gpio_softc *sc;
657 
658 	sc = device_get_softc(dev);
659 
660 	if (pin >= sc->gpio_npins)
661 		return (EINVAL);
662 
663 	mtx_lock_spin(&sc->sc_mtx);
664 	WRITE4(sc, IMX_GPIO_DR_REG,
665 	    (READ4(sc, IMX_GPIO_DR_REG) ^ (1U << pin)));
666 	mtx_unlock_spin(&sc->sc_mtx);
667 
668 	return (0);
669 }
670 
671 static int
672 imx51_gpio_probe(device_t dev)
673 {
674 
675 	if (!ofw_bus_status_okay(dev))
676 		return (ENXIO);
677 
678 	if (ofw_bus_search_compatible(dev, compat_data)->ocd_data != 0) {
679 		device_set_desc(dev, "Freescale i.MX GPIO Controller");
680 		return (BUS_PROBE_DEFAULT);
681 	}
682 
683 	return (ENXIO);
684 }
685 
686 static int
687 imx51_gpio_attach(device_t dev)
688 {
689 	struct imx51_gpio_softc *sc;
690 	int i, irq, unit;
691 
692 	sc = device_get_softc(dev);
693 	sc->dev = dev;
694 	sc->gpio_npins = NGPIO;
695 
696 	mtx_init(&sc->sc_mtx, device_get_nameunit(sc->dev), NULL, MTX_SPIN);
697 
698 	if (bus_alloc_resources(dev, imx_gpio_spec, sc->sc_res)) {
699 		device_printf(dev, "could not allocate resources\n");
700 		bus_release_resources(dev, imx_gpio_spec, sc->sc_res);
701 		mtx_destroy(&sc->sc_mtx);
702 		return (ENXIO);
703 	}
704 
705 	sc->sc_iot = rman_get_bustag(sc->sc_res[0]);
706 	sc->sc_ioh = rman_get_bushandle(sc->sc_res[0]);
707 	/*
708 	 * Mask off all interrupts in hardware, then set up interrupt handling.
709 	 */
710 	WRITE4(sc, IMX_GPIO_IMR_REG, 0);
711 	for (irq = 0; irq < 2; irq++) {
712 #ifdef INTRNG
713 		if ((bus_setup_intr(dev, sc->sc_res[1 + irq], INTR_TYPE_CLK,
714 		    gpio_pic_filter, NULL, sc, &sc->gpio_ih[irq]))) {
715 			device_printf(dev,
716 			    "WARNING: unable to register interrupt handler\n");
717 			imx51_gpio_detach(dev);
718 			return (ENXIO);
719 		}
720 #endif
721 	}
722 
723 	unit = device_get_unit(dev);
724 	for (i = 0; i < sc->gpio_npins; i++) {
725  		sc->gpio_pins[i].gp_pin = i;
726  		sc->gpio_pins[i].gp_caps = DEFAULT_CAPS;
727  		sc->gpio_pins[i].gp_flags =
728  		    (READ4(sc, IMX_GPIO_OE_REG) & (1U << i)) ? GPIO_PIN_OUTPUT :
729  		    GPIO_PIN_INPUT;
730  		snprintf(sc->gpio_pins[i].gp_name, GPIOMAXNAME,
731  		    "imx_gpio%d.%d", unit, i);
732 	}
733 
734 #ifdef INTRNG
735 	gpio_pic_register_isrcs(sc);
736 	intr_pic_register(dev, OF_xref_from_node(ofw_bus_get_node(dev)));
737 #endif
738 	sc->sc_busdev = gpiobus_attach_bus(dev);
739 
740 	if (sc->sc_busdev == NULL) {
741 		imx51_gpio_detach(dev);
742 		return (ENXIO);
743 	}
744 
745 	return (0);
746 }
747 
748 static int
749 imx51_gpio_detach(device_t dev)
750 {
751 	int irq;
752 	struct imx51_gpio_softc *sc;
753 
754 	sc = device_get_softc(dev);
755 
756 	gpiobus_detach_bus(dev);
757 	for (irq = 1; irq <= 2; irq++) {
758 		if (sc->gpio_ih[irq])
759 			bus_teardown_intr(dev, sc->sc_res[irq], sc->gpio_ih[irq]);
760 	}
761 	bus_release_resources(dev, imx_gpio_spec, sc->sc_res);
762 	mtx_destroy(&sc->sc_mtx);
763 
764 	return(0);
765 }
766 
767 static device_method_t imx51_gpio_methods[] = {
768 	DEVMETHOD(device_probe,		imx51_gpio_probe),
769 	DEVMETHOD(device_attach,	imx51_gpio_attach),
770 	DEVMETHOD(device_detach,	imx51_gpio_detach),
771 
772 #ifdef INTRNG
773 	/* Interrupt controller interface */
774 	DEVMETHOD(pic_disable_intr,	gpio_pic_disable_intr),
775 	DEVMETHOD(pic_enable_intr,	gpio_pic_enable_intr),
776 	DEVMETHOD(pic_map_intr,		gpio_pic_map_intr),
777 	DEVMETHOD(pic_setup_intr,	gpio_pic_setup_intr),
778 	DEVMETHOD(pic_teardown_intr,	gpio_pic_teardown_intr),
779 	DEVMETHOD(pic_post_filter,	gpio_pic_post_filter),
780 	DEVMETHOD(pic_post_ithread,	gpio_pic_post_ithread),
781 	DEVMETHOD(pic_pre_ithread,	gpio_pic_pre_ithread),
782 #endif
783 
784 	/* GPIO protocol */
785 	DEVMETHOD(gpio_get_bus,		imx51_gpio_get_bus),
786 	DEVMETHOD(gpio_pin_max,		imx51_gpio_pin_max),
787 	DEVMETHOD(gpio_pin_getname,	imx51_gpio_pin_getname),
788 	DEVMETHOD(gpio_pin_getflags,	imx51_gpio_pin_getflags),
789 	DEVMETHOD(gpio_pin_getcaps,	imx51_gpio_pin_getcaps),
790 	DEVMETHOD(gpio_pin_setflags,	imx51_gpio_pin_setflags),
791 	DEVMETHOD(gpio_pin_get,		imx51_gpio_pin_get),
792 	DEVMETHOD(gpio_pin_set,		imx51_gpio_pin_set),
793 	DEVMETHOD(gpio_pin_toggle,	imx51_gpio_pin_toggle),
794 	{0, 0},
795 };
796 
797 static driver_t imx51_gpio_driver = {
798 	"gpio",
799 	imx51_gpio_methods,
800 	sizeof(struct imx51_gpio_softc),
801 };
802 static devclass_t imx51_gpio_devclass;
803 
804 DRIVER_MODULE(imx51_gpio, simplebus, imx51_gpio_driver, imx51_gpio_devclass,
805     0, 0);
806