xref: /freebsd/sys/arm/freescale/imx/imx_gpio.c (revision 069ac184)
1 /*-
2  * Copyright (c) 2012, 2013 The FreeBSD Foundation
3  *
4  * This software was developed by Oleksandr Rybalko under sponsorship
5  * from the FreeBSD Foundation.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1.	Redistributions of source code must retain the above copyright
11  *	notice, this list of conditions and the following disclaimer.
12  * 2.	Redistributions in binary form must reproduce the above copyright
13  *	notice, this list of conditions and the following disclaimer in the
14  *	documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 /*
30  * Freescale i.MX515 GPIO driver.
31  */
32 
33 #include <sys/cdefs.h>
34 #include "opt_platform.h"
35 
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/bus.h>
39 
40 #include <sys/kernel.h>
41 #include <sys/module.h>
42 #include <sys/rman.h>
43 #include <sys/lock.h>
44 #include <sys/mutex.h>
45 #include <sys/gpio.h>
46 #include <sys/proc.h>
47 
48 #include <machine/bus.h>
49 #include <machine/intr.h>
50 #include <machine/resource.h>
51 
52 #include <dev/gpio/gpiobusvar.h>
53 #include <dev/ofw/openfirm.h>
54 #include <dev/ofw/ofw_bus.h>
55 #include <dev/ofw/ofw_bus_subr.h>
56 
57 #if defined(__aarch64__)
58 #define	IMX_ENABLE_CLOCKS
59 #endif
60 
61 #ifdef IMX_ENABLE_CLOCKS
62 #include <dev/extres/clk/clk.h>
63 #endif
64 
65 #include "gpio_if.h"
66 
67 #ifdef INTRNG
68 #include "pic_if.h"
69 #endif
70 
71 #define	WRITE4(_sc, _r, _v)						\
72 	    bus_space_write_4((_sc)->sc_iot, (_sc)->sc_ioh, (_r), (_v))
73 #define	READ4(_sc, _r)							\
74 	    bus_space_read_4((_sc)->sc_iot, (_sc)->sc_ioh, (_r))
75 #define	SET4(_sc, _r, _m)						\
76 	    WRITE4((_sc), (_r), READ4((_sc), (_r)) | (_m))
77 #define	CLEAR4(_sc, _r, _m)						\
78 	    WRITE4((_sc), (_r), READ4((_sc), (_r)) & ~(_m))
79 
80 /* Registers definition for Freescale i.MX515 GPIO controller */
81 
82 #define	IMX_GPIO_DR_REG		0x000 /* Pin Data */
83 #define	IMX_GPIO_OE_REG		0x004 /* Set Pin Output */
84 #define	IMX_GPIO_PSR_REG	0x008 /* Pad Status */
85 #define	IMX_GPIO_ICR1_REG	0x00C /* Interrupt Configuration */
86 #define	IMX_GPIO_ICR2_REG	0x010 /* Interrupt Configuration */
87 #define		GPIO_ICR_COND_LOW	0
88 #define		GPIO_ICR_COND_HIGH	1
89 #define		GPIO_ICR_COND_RISE	2
90 #define		GPIO_ICR_COND_FALL	3
91 #define		GPIO_ICR_COND_MASK	0x3
92 #define	IMX_GPIO_IMR_REG	0x014 /* Interrupt Mask Register */
93 #define	IMX_GPIO_ISR_REG	0x018 /* Interrupt Status Register */
94 #define	IMX_GPIO_EDGE_REG	0x01C /* Edge Detect Register */
95 
96 #ifdef INTRNG
97 #define	DEFAULT_CAPS	(GPIO_PIN_INPUT | GPIO_PIN_OUTPUT | \
98     GPIO_INTR_LEVEL_LOW | GPIO_INTR_LEVEL_HIGH | GPIO_INTR_EDGE_RISING | \
99     GPIO_INTR_EDGE_FALLING | GPIO_INTR_EDGE_BOTH)
100 #else
101 #define	DEFAULT_CAPS	(GPIO_PIN_INPUT | GPIO_PIN_OUTPUT)
102 #endif
103 
104 #define	NGPIO		32
105 
106 #ifdef INTRNG
107 struct gpio_irqsrc {
108 	struct intr_irqsrc	gi_isrc;
109 	u_int			gi_irq;
110 	uint32_t		gi_mode;
111 };
112 #endif
113 
114 struct imx51_gpio_softc {
115 	device_t		dev;
116 	device_t		sc_busdev;
117 	struct mtx		sc_mtx;
118 	struct resource		*sc_res[3]; /* 1 x mem, 2 x IRQ */
119 	void			*gpio_ih[2];
120 	bus_space_tag_t		sc_iot;
121 	bus_space_handle_t	sc_ioh;
122 	int			gpio_npins;
123 	struct gpio_pin		gpio_pins[NGPIO];
124 #ifdef INTRNG
125 	struct gpio_irqsrc 	gpio_pic_irqsrc[NGPIO];
126 #endif
127 #ifdef IMX_ENABLE_CLOCKS
128 	clk_t			clk;
129 #endif
130 };
131 
132 static struct ofw_compat_data compat_data[] = {
133 	{"fsl,imx8mq-gpio",	1},
134 	{"fsl,imx6q-gpio",	1},
135 	{"fsl,imx53-gpio",	1},
136 	{"fsl,imx51-gpio",	1},
137 	{NULL,			0}
138 };
139 
140 static struct resource_spec imx_gpio_spec[] = {
141 	{ SYS_RES_MEMORY,	0,	RF_ACTIVE },
142 	{ SYS_RES_IRQ,		0,	RF_ACTIVE },
143 	{ SYS_RES_IRQ,		1,	RF_ACTIVE },
144 	{ -1, 0 }
145 };
146 #define	FIRST_IRQRES	1
147 #define	NUM_IRQRES	2
148 
149 /*
150  * Helpers
151  */
152 static void imx51_gpio_pin_configure(struct imx51_gpio_softc *,
153     struct gpio_pin *, uint32_t);
154 
155 /*
156  * Driver stuff
157  */
158 static int imx51_gpio_probe(device_t);
159 static int imx51_gpio_attach(device_t);
160 static int imx51_gpio_detach(device_t);
161 
162 /*
163  * GPIO interface
164  */
165 static device_t imx51_gpio_get_bus(device_t);
166 static int imx51_gpio_pin_max(device_t, int *);
167 static int imx51_gpio_pin_getcaps(device_t, uint32_t, uint32_t *);
168 static int imx51_gpio_pin_getflags(device_t, uint32_t, uint32_t *);
169 static int imx51_gpio_pin_getname(device_t, uint32_t, char *);
170 static int imx51_gpio_pin_setflags(device_t, uint32_t, uint32_t);
171 static int imx51_gpio_pin_set(device_t, uint32_t, unsigned int);
172 static int imx51_gpio_pin_get(device_t, uint32_t, unsigned int *);
173 static int imx51_gpio_pin_toggle(device_t, uint32_t pin);
174 
175 #ifdef INTRNG
176 static int
177 gpio_pic_map_fdt(struct imx51_gpio_softc *sc, struct intr_map_data_fdt *daf,
178     u_int *irqp, uint32_t *modep)
179 {
180 	u_int irq;
181 	uint32_t mode;
182 
183 	/*
184 	 * From devicetree/bindings/gpio/fsl-imx-gpio.txt:
185 	 *  #interrupt-cells:  2. The first cell is the GPIO number. The second
186 	 *  cell bits[3:0] is used to specify trigger type and level flags:
187 	 *    1 = low-to-high edge triggered.
188 	 *    2 = high-to-low edge triggered.
189 	 *    4 = active high level-sensitive.
190 	 *    8 = active low level-sensitive.
191 	 * We can do any single one of these modes, and also edge low+high
192 	 * (i.e., trigger on both edges); other combinations are not supported.
193 	 */
194 
195 	if (daf->ncells != 2) {
196 		device_printf(sc->dev, "Invalid #interrupt-cells\n");
197 		return (EINVAL);
198 	}
199 
200 	irq = daf->cells[0];
201 	if (irq >= sc->gpio_npins) {
202 		device_printf(sc->dev, "Invalid interrupt number %u\n", irq);
203 		return (EINVAL);
204 	}
205 	switch (daf->cells[1]) {
206 	case 1:
207 		mode = GPIO_INTR_EDGE_RISING;
208 		break;
209 	case 2:
210 		mode = GPIO_INTR_EDGE_FALLING;
211 		break;
212 	case 3:
213 		mode = GPIO_INTR_EDGE_BOTH;
214 		break;
215 	case 4:
216 		mode = GPIO_INTR_LEVEL_HIGH;
217 		break;
218 	case 8:
219 		mode = GPIO_INTR_LEVEL_LOW;
220 		break;
221 	default:
222 		device_printf(sc->dev, "Unsupported interrupt mode 0x%2x\n",
223 		    daf->cells[1]);
224 		return (ENOTSUP);
225 	}
226 	*irqp = irq;
227 	if (modep != NULL)
228 		*modep = mode;
229 	return (0);
230 }
231 
232 static int
233 gpio_pic_map_gpio(struct imx51_gpio_softc *sc, struct intr_map_data_gpio *dag,
234     u_int *irqp, uint32_t *modep)
235 {
236 	u_int irq;
237 
238 	irq = dag->gpio_pin_num;
239 	if (irq >= sc->gpio_npins) {
240 		device_printf(sc->dev, "Invalid interrupt number %u\n", irq);
241 		return (EINVAL);
242 	}
243 
244 	switch (dag->gpio_intr_mode) {
245 	case GPIO_INTR_LEVEL_LOW:
246 	case GPIO_INTR_LEVEL_HIGH:
247 	case GPIO_INTR_EDGE_RISING:
248 	case GPIO_INTR_EDGE_FALLING:
249 	case GPIO_INTR_EDGE_BOTH:
250 		break;
251 	default:
252 		device_printf(sc->dev, "Unsupported interrupt mode 0x%8x\n",
253 		    dag->gpio_intr_mode);
254 		return (EINVAL);
255 	}
256 
257 	*irqp = irq;
258 	if (modep != NULL)
259 		*modep = dag->gpio_intr_mode;
260 	return (0);
261 }
262 
263 static int
264 gpio_pic_map(struct imx51_gpio_softc *sc, struct intr_map_data *data,
265     u_int *irqp, uint32_t *modep)
266 {
267 
268 	switch (data->type) {
269 	case INTR_MAP_DATA_FDT:
270 		return (gpio_pic_map_fdt(sc, (struct intr_map_data_fdt *)data,
271 		    irqp, modep));
272 	case INTR_MAP_DATA_GPIO:
273 		return (gpio_pic_map_gpio(sc, (struct intr_map_data_gpio *)data,
274 		    irqp, modep));
275 	default:
276 		return (ENOTSUP);
277 	}
278 }
279 
280 static int
281 gpio_pic_map_intr(device_t dev, struct intr_map_data *data,
282     struct intr_irqsrc **isrcp)
283 {
284 	int error;
285 	u_int irq;
286 	struct imx51_gpio_softc *sc;
287 
288 	sc = device_get_softc(dev);
289 	error = gpio_pic_map(sc, data, &irq, NULL);
290 	if (error == 0)
291 		*isrcp = &sc->gpio_pic_irqsrc[irq].gi_isrc;
292 	return (error);
293 }
294 
295 static int
296 gpio_pic_teardown_intr(device_t dev, struct intr_irqsrc *isrc,
297     struct resource *res, struct intr_map_data *data)
298 {
299 	struct imx51_gpio_softc *sc;
300 	struct gpio_irqsrc *gi;
301 
302 	sc = device_get_softc(dev);
303 	if (isrc->isrc_handlers == 0) {
304 		gi = (struct gpio_irqsrc *)isrc;
305 		gi->gi_mode = GPIO_INTR_CONFORM;
306 
307 		// XXX Not sure this is necessary
308 		mtx_lock_spin(&sc->sc_mtx);
309 		CLEAR4(sc, IMX_GPIO_IMR_REG, (1U << gi->gi_irq));
310 		WRITE4(sc, IMX_GPIO_ISR_REG, (1U << gi->gi_irq));
311 		mtx_unlock_spin(&sc->sc_mtx);
312 	}
313 	return (0);
314 }
315 
316 static int
317 gpio_pic_setup_intr(device_t dev, struct intr_irqsrc *isrc,
318     struct resource *res, struct intr_map_data *data)
319 {
320 	struct imx51_gpio_softc *sc;
321 	struct gpio_irqsrc *gi;
322 	int error;
323 	u_int icfg, irq, reg, shift, wrk;
324 	uint32_t mode;
325 
326 	if (data == NULL)
327 		return (ENOTSUP);
328 
329 	sc = device_get_softc(dev);
330 	gi = (struct gpio_irqsrc *)isrc;
331 
332 	/* Get config for interrupt. */
333 	error = gpio_pic_map(sc, data, &irq, &mode);
334 	if (error != 0)
335 		return (error);
336 	if (gi->gi_irq != irq)
337 		return (EINVAL);
338 
339 	/* Compare config if this is not first setup. */
340 	if (isrc->isrc_handlers != 0)
341 		return (gi->gi_mode == mode ? 0 : EINVAL);
342 	gi->gi_mode = mode;
343 
344 	/*
345 	 * To interrupt on both edges we have to use the EDGE register.  The
346 	 * manual says it only exists for backwards compatibilty with older imx
347 	 * chips, but it's also the only way to configure interrupting on both
348 	 * edges.  If the EDGE bit is on, the corresponding ICRn bit is ignored.
349 	 */
350 	mtx_lock_spin(&sc->sc_mtx);
351 	if (mode == GPIO_INTR_EDGE_BOTH) {
352 		SET4(sc, IMX_GPIO_EDGE_REG, (1u << irq));
353 	} else {
354 		CLEAR4(sc, IMX_GPIO_EDGE_REG, (1u << irq));
355 		switch (mode) {
356 		default:
357 			/* silence warnings; default can't actually happen. */
358 			/* FALLTHROUGH */
359 		case GPIO_INTR_LEVEL_LOW:
360 			icfg = GPIO_ICR_COND_LOW;
361 			break;
362 		case GPIO_INTR_LEVEL_HIGH:
363 			icfg = GPIO_ICR_COND_HIGH;
364 			break;
365 		case GPIO_INTR_EDGE_RISING:
366 			icfg = GPIO_ICR_COND_RISE;
367 			break;
368 		case GPIO_INTR_EDGE_FALLING:
369 			icfg = GPIO_ICR_COND_FALL;
370 			break;
371 		}
372 		if (irq < 16) {
373 			reg = IMX_GPIO_ICR1_REG;
374 			shift = 2 * irq;
375 		} else {
376 			reg = IMX_GPIO_ICR2_REG;
377 			shift = 2 * (irq - 16);
378 		}
379 		wrk = READ4(sc, reg);
380 		wrk &= ~(GPIO_ICR_COND_MASK << shift);
381 		wrk |= icfg << shift;
382 		WRITE4(sc, reg, wrk);
383 	}
384 	WRITE4(sc, IMX_GPIO_ISR_REG, (1u << irq));
385 	SET4(sc, IMX_GPIO_IMR_REG, (1u << irq));
386 	mtx_unlock_spin(&sc->sc_mtx);
387 
388 	return (0);
389 }
390 
391 /*
392  * this is mask_intr
393  */
394 static void
395 gpio_pic_disable_intr(device_t dev, struct intr_irqsrc *isrc)
396 {
397 	struct imx51_gpio_softc *sc;
398 	u_int irq;
399 
400 	sc = device_get_softc(dev);
401 	irq = ((struct gpio_irqsrc *)isrc)->gi_irq;
402 
403 	mtx_lock_spin(&sc->sc_mtx);
404 	CLEAR4(sc, IMX_GPIO_IMR_REG, (1U << irq));
405 	mtx_unlock_spin(&sc->sc_mtx);
406 }
407 
408 /*
409  * this is unmask_intr
410  */
411 static void
412 gpio_pic_enable_intr(device_t dev, struct intr_irqsrc *isrc)
413 {
414 	struct imx51_gpio_softc *sc;
415 	u_int irq;
416 
417 	sc = device_get_softc(dev);
418 	irq = ((struct gpio_irqsrc *)isrc)->gi_irq;
419 
420 	mtx_lock_spin(&sc->sc_mtx);
421 	SET4(sc, IMX_GPIO_IMR_REG, (1U << irq));
422 	mtx_unlock_spin(&sc->sc_mtx);
423 }
424 
425 static void
426 gpio_pic_post_filter(device_t dev, struct intr_irqsrc *isrc)
427 {
428 	struct imx51_gpio_softc *sc;
429 	u_int irq;
430 
431 	sc = device_get_softc(dev);
432 	irq = ((struct gpio_irqsrc *)isrc)->gi_irq;
433 
434 	arm_irq_memory_barrier(0);
435         /* EOI.  W1C reg so no r-m-w, no locking needed. */
436 	WRITE4(sc, IMX_GPIO_ISR_REG, (1U << irq));
437 }
438 
439 static void
440 gpio_pic_post_ithread(device_t dev, struct intr_irqsrc *isrc)
441 {
442 	struct imx51_gpio_softc *sc;
443 	u_int irq;
444 
445 	sc = device_get_softc(dev);
446 	irq = ((struct gpio_irqsrc *)isrc)->gi_irq;
447 
448 	arm_irq_memory_barrier(0);
449 	/* EOI.  W1C reg so no r-m-w, no locking needed. */
450 	WRITE4(sc, IMX_GPIO_ISR_REG, (1U << irq));
451 	gpio_pic_enable_intr(dev, isrc);
452 }
453 
454 static void
455 gpio_pic_pre_ithread(device_t dev, struct intr_irqsrc *isrc)
456 {
457 	gpio_pic_disable_intr(dev, isrc);
458 }
459 
460 static int
461 gpio_pic_filter(void *arg)
462 {
463 	struct imx51_gpio_softc *sc;
464 	struct intr_irqsrc *isrc;
465 	uint32_t i, interrupts;
466 
467 	sc = arg;
468 	mtx_lock_spin(&sc->sc_mtx);
469 	interrupts = READ4(sc, IMX_GPIO_ISR_REG) & READ4(sc, IMX_GPIO_IMR_REG);
470 	mtx_unlock_spin(&sc->sc_mtx);
471 
472 	for (i = 0; interrupts != 0; i++, interrupts >>= 1) {
473 		if ((interrupts & 0x1) == 0)
474 			continue;
475 		isrc = &sc->gpio_pic_irqsrc[i].gi_isrc;
476 		if (intr_isrc_dispatch(isrc, curthread->td_intr_frame) != 0) {
477 			gpio_pic_disable_intr(sc->dev, isrc);
478 			gpio_pic_post_filter(sc->dev, isrc);
479 			device_printf(sc->dev, "Stray irq %u disabled\n", i);
480 		}
481 	}
482 
483 	return (FILTER_HANDLED);
484 }
485 
486 /*
487  * Initialize our isrcs and register them with intrng.
488  */
489 static int
490 gpio_pic_register_isrcs(struct imx51_gpio_softc *sc)
491 {
492 	int error;
493 	uint32_t irq;
494 	const char *name;
495 
496 	name = device_get_nameunit(sc->dev);
497 	for (irq = 0; irq < NGPIO; irq++) {
498 		sc->gpio_pic_irqsrc[irq].gi_irq = irq;
499 		sc->gpio_pic_irqsrc[irq].gi_mode = GPIO_INTR_CONFORM;
500 
501 		error = intr_isrc_register(&sc->gpio_pic_irqsrc[irq].gi_isrc,
502 		    sc->dev, 0, "%s,%u", name, irq);
503 		if (error != 0) {
504 			/* XXX call intr_isrc_deregister() */
505 			device_printf(sc->dev, "%s failed", __func__);
506 			return (error);
507 		}
508 	}
509 	return (0);
510 }
511 #endif
512 
513 /*
514  *
515  */
516 static void
517 imx51_gpio_pin_configure(struct imx51_gpio_softc *sc, struct gpio_pin *pin,
518     unsigned int flags)
519 {
520 	u_int newflags, pad;
521 
522 	mtx_lock_spin(&sc->sc_mtx);
523 
524 	/*
525 	 * Manage input/output; other flags not supported yet (maybe not ever,
526 	 * since we have no connection to the pad config registers from here).
527 	 *
528 	 * When setting a pin to output, honor the PRESET_[LOW,HIGH] flags if
529 	 * present.  Otherwise, for glitchless transitions on pins with pulls,
530 	 * read the current state of the pad and preset the DR register to drive
531 	 * the current value onto the pin before enabling the pin for output.
532 	 *
533 	 * Note that changes to pin->gp_flags must be acccumulated in newflags
534 	 * and stored with a single writeback to gp_flags at the end, to enable
535 	 * unlocked reads of that value elsewhere. This is only about unlocked
536 	 * access to gp_flags from elsewhere; we still use locking in this
537 	 * function to protect r-m-w access to the hardware registers.
538 	 */
539 	if (flags & (GPIO_PIN_INPUT | GPIO_PIN_OUTPUT)) {
540 		newflags = pin->gp_flags & ~(GPIO_PIN_INPUT | GPIO_PIN_OUTPUT);
541 		if (flags & GPIO_PIN_OUTPUT) {
542 			if (flags & GPIO_PIN_PRESET_LOW) {
543 				pad = 0;
544 			} else if (flags & GPIO_PIN_PRESET_HIGH) {
545 				pad = 1;
546 			} else {
547 				if (flags & GPIO_PIN_OPENDRAIN)
548 					pad = READ4(sc, IMX_GPIO_PSR_REG);
549 				else
550 					pad = READ4(sc, IMX_GPIO_DR_REG);
551 				pad = (pad >> pin->gp_pin) & 1;
552 			}
553 			newflags |= GPIO_PIN_OUTPUT;
554 			SET4(sc, IMX_GPIO_DR_REG, (pad << pin->gp_pin));
555 			SET4(sc, IMX_GPIO_OE_REG, (1U << pin->gp_pin));
556 		} else {
557 			newflags |= GPIO_PIN_INPUT;
558 			CLEAR4(sc, IMX_GPIO_OE_REG, (1U << pin->gp_pin));
559 		}
560 		pin->gp_flags = newflags;
561 	}
562 
563 	mtx_unlock_spin(&sc->sc_mtx);
564 }
565 
566 static device_t
567 imx51_gpio_get_bus(device_t dev)
568 {
569 	struct imx51_gpio_softc *sc;
570 
571 	sc = device_get_softc(dev);
572 
573 	return (sc->sc_busdev);
574 }
575 
576 static int
577 imx51_gpio_pin_max(device_t dev, int *maxpin)
578 {
579 	struct imx51_gpio_softc *sc;
580 
581 	sc = device_get_softc(dev);
582 	*maxpin = sc->gpio_npins - 1;
583 
584 	return (0);
585 }
586 
587 static int
588 imx51_gpio_pin_getcaps(device_t dev, uint32_t pin, uint32_t *caps)
589 {
590 	struct imx51_gpio_softc *sc;
591 
592 	sc = device_get_softc(dev);
593 
594 	if (pin >= sc->gpio_npins)
595 		return (EINVAL);
596 
597 	*caps = sc->gpio_pins[pin].gp_caps;
598 
599 	return (0);
600 }
601 
602 static int
603 imx51_gpio_pin_getflags(device_t dev, uint32_t pin, uint32_t *flags)
604 {
605 	struct imx51_gpio_softc *sc;
606 
607 	sc = device_get_softc(dev);
608 
609 	if (pin >= sc->gpio_npins)
610 		return (EINVAL);
611 
612 	*flags = sc->gpio_pins[pin].gp_flags;
613 
614 	return (0);
615 }
616 
617 static int
618 imx51_gpio_pin_getname(device_t dev, uint32_t pin, char *name)
619 {
620 	struct imx51_gpio_softc *sc;
621 
622 	sc = device_get_softc(dev);
623 	if (pin >= sc->gpio_npins)
624 		return (EINVAL);
625 
626 	mtx_lock_spin(&sc->sc_mtx);
627 	memcpy(name, sc->gpio_pins[pin].gp_name, GPIOMAXNAME);
628 	mtx_unlock_spin(&sc->sc_mtx);
629 
630 	return (0);
631 }
632 
633 static int
634 imx51_gpio_pin_setflags(device_t dev, uint32_t pin, uint32_t flags)
635 {
636 	struct imx51_gpio_softc *sc;
637 
638 	sc = device_get_softc(dev);
639 
640 	if (pin >= sc->gpio_npins)
641 		return (EINVAL);
642 
643 	imx51_gpio_pin_configure(sc, &sc->gpio_pins[pin], flags);
644 
645 	return (0);
646 }
647 
648 static int
649 imx51_gpio_pin_set(device_t dev, uint32_t pin, unsigned int value)
650 {
651 	struct imx51_gpio_softc *sc;
652 
653 	sc = device_get_softc(dev);
654 
655 	if (pin >= sc->gpio_npins)
656 		return (EINVAL);
657 
658 	mtx_lock_spin(&sc->sc_mtx);
659 	if (value)
660 		SET4(sc, IMX_GPIO_DR_REG, (1U << pin));
661 	else
662 		CLEAR4(sc, IMX_GPIO_DR_REG, (1U << pin));
663 	mtx_unlock_spin(&sc->sc_mtx);
664 
665 	return (0);
666 }
667 
668 static int
669 imx51_gpio_pin_get(device_t dev, uint32_t pin, unsigned int *val)
670 {
671 	struct imx51_gpio_softc *sc;
672 
673 	sc = device_get_softc(dev);
674 
675 	if (pin >= sc->gpio_npins)
676 		return (EINVAL);
677 
678 	/*
679 	 * Normally a pin set for output can be read by reading the DR reg which
680 	 * indicates what value is being driven to that pin.  The exception is
681 	 * pins configured for open-drain mode, in which case we have to read
682 	 * the pad status register in case the pin is being driven externally.
683 	 * Doing so requires that the SION bit be configured in pinmux, which
684 	 * isn't the case for most normal gpio pins, so only try to read via PSR
685 	 * if the OPENDRAIN flag is set, and it's the user's job to correctly
686 	 * configure SION along with open-drain output mode for those pins.
687 	 */
688 	if (sc->gpio_pins[pin].gp_flags & GPIO_PIN_OPENDRAIN)
689 		*val = (READ4(sc, IMX_GPIO_PSR_REG) >> pin) & 1;
690 	else
691 		*val = (READ4(sc, IMX_GPIO_DR_REG) >> pin) & 1;
692 
693 	return (0);
694 }
695 
696 static int
697 imx51_gpio_pin_toggle(device_t dev, uint32_t pin)
698 {
699 	struct imx51_gpio_softc *sc;
700 
701 	sc = device_get_softc(dev);
702 
703 	if (pin >= sc->gpio_npins)
704 		return (EINVAL);
705 
706 	mtx_lock_spin(&sc->sc_mtx);
707 	WRITE4(sc, IMX_GPIO_DR_REG,
708 	    (READ4(sc, IMX_GPIO_DR_REG) ^ (1U << pin)));
709 	mtx_unlock_spin(&sc->sc_mtx);
710 
711 	return (0);
712 }
713 
714 static int
715 imx51_gpio_pin_access_32(device_t dev, uint32_t first_pin, uint32_t clear_pins,
716     uint32_t change_pins, uint32_t *orig_pins)
717 {
718 	struct imx51_gpio_softc *sc;
719 
720 	if (first_pin != 0)
721 		return (EINVAL);
722 
723 	sc = device_get_softc(dev);
724 
725 	if (orig_pins != NULL)
726 		*orig_pins = READ4(sc, IMX_GPIO_DR_REG);
727 
728 	if ((clear_pins | change_pins) != 0) {
729 		mtx_lock_spin(&sc->sc_mtx);
730 		WRITE4(sc, IMX_GPIO_DR_REG,
731 		    (READ4(sc, IMX_GPIO_DR_REG) & ~clear_pins) ^ change_pins);
732 		mtx_unlock_spin(&sc->sc_mtx);
733 	}
734 
735 	return (0);
736 }
737 
738 static int
739 imx51_gpio_pin_config_32(device_t dev, uint32_t first_pin, uint32_t num_pins,
740     uint32_t *pin_flags)
741 {
742 	struct imx51_gpio_softc *sc;
743 	u_int i;
744 	uint32_t bit, drclr, drset, flags, oeclr, oeset, pads;
745 
746 	sc = device_get_softc(dev);
747 
748 	if (first_pin != 0 || num_pins > sc->gpio_npins)
749 		return (EINVAL);
750 
751 	drclr = drset = oeclr = oeset = 0;
752 	pads = READ4(sc, IMX_GPIO_DR_REG);
753 
754 	for (i = 0; i < num_pins; ++i) {
755 		bit = 1u << i;
756 		flags = pin_flags[i];
757 		if (flags & GPIO_PIN_INPUT) {
758 			oeclr |= bit;
759 		} else if (flags & GPIO_PIN_OUTPUT) {
760 			oeset |= bit;
761 			if (flags & GPIO_PIN_PRESET_LOW)
762 				drclr |= bit;
763 			else if (flags & GPIO_PIN_PRESET_HIGH)
764 				drset |= bit;
765 			else /* Drive whatever it's now pulled to. */
766 				drset |= pads & bit;
767 		}
768 	}
769 
770 	mtx_lock_spin(&sc->sc_mtx);
771 	WRITE4(sc, IMX_GPIO_DR_REG,
772 	    (READ4(sc, IMX_GPIO_DR_REG) & ~drclr) | drset);
773 	WRITE4(sc, IMX_GPIO_OE_REG,
774 	    (READ4(sc, IMX_GPIO_OE_REG) & ~oeclr) | oeset);
775 	mtx_unlock_spin(&sc->sc_mtx);
776 
777 	return (0);
778 }
779 
780 static int
781 imx51_gpio_probe(device_t dev)
782 {
783 
784 	if (!ofw_bus_status_okay(dev))
785 		return (ENXIO);
786 
787 	if (ofw_bus_search_compatible(dev, compat_data)->ocd_data != 0) {
788 		device_set_desc(dev, "Freescale i.MX GPIO Controller");
789 		return (BUS_PROBE_DEFAULT);
790 	}
791 
792 	return (ENXIO);
793 }
794 
795 static int
796 imx51_gpio_attach(device_t dev)
797 {
798 	struct imx51_gpio_softc *sc;
799 	int i, irq, unit;
800 #ifdef IMX_ENABLE_CLOCKS
801 	int err;
802 #endif
803 
804 	sc = device_get_softc(dev);
805 	sc->dev = dev;
806 	sc->gpio_npins = NGPIO;
807 
808 	mtx_init(&sc->sc_mtx, device_get_nameunit(sc->dev), NULL, MTX_SPIN);
809 
810 #ifdef IMX_ENABLE_CLOCKS
811 	if (clk_get_by_ofw_index(sc->dev, 0, 0, &sc->clk) != 0) {
812 		device_printf(dev, "could not get clock");
813 		return (ENOENT);
814 	}
815 
816 	err = clk_enable(sc->clk);
817 	if (err != 0) {
818 		device_printf(sc->dev, "could not enable ipg clock\n");
819 		return (err);
820 	}
821 #endif
822 
823 	if (bus_alloc_resources(dev, imx_gpio_spec, sc->sc_res)) {
824 		device_printf(dev, "could not allocate resources\n");
825 		bus_release_resources(dev, imx_gpio_spec, sc->sc_res);
826 		mtx_destroy(&sc->sc_mtx);
827 		return (ENXIO);
828 	}
829 
830 	sc->sc_iot = rman_get_bustag(sc->sc_res[0]);
831 	sc->sc_ioh = rman_get_bushandle(sc->sc_res[0]);
832 	/*
833 	 * Mask off all interrupts in hardware, then set up interrupt handling.
834 	 */
835 	WRITE4(sc, IMX_GPIO_IMR_REG, 0);
836 	for (irq = 0; irq < 2; irq++) {
837 #ifdef INTRNG
838 		if ((bus_setup_intr(dev, sc->sc_res[1 + irq], INTR_TYPE_CLK,
839 		    gpio_pic_filter, NULL, sc, &sc->gpio_ih[irq]))) {
840 			device_printf(dev,
841 			    "WARNING: unable to register interrupt handler\n");
842 			imx51_gpio_detach(dev);
843 			return (ENXIO);
844 		}
845 #endif
846 	}
847 
848 	unit = device_get_unit(dev);
849 	for (i = 0; i < sc->gpio_npins; i++) {
850  		sc->gpio_pins[i].gp_pin = i;
851  		sc->gpio_pins[i].gp_caps = DEFAULT_CAPS;
852  		sc->gpio_pins[i].gp_flags =
853  		    (READ4(sc, IMX_GPIO_OE_REG) & (1U << i)) ? GPIO_PIN_OUTPUT :
854  		    GPIO_PIN_INPUT;
855  		snprintf(sc->gpio_pins[i].gp_name, GPIOMAXNAME,
856  		    "GPIO%d_IO%02d", unit + 1, i);
857 	}
858 
859 #ifdef INTRNG
860 	gpio_pic_register_isrcs(sc);
861 	intr_pic_register(dev, OF_xref_from_node(ofw_bus_get_node(dev)));
862 #endif
863 	sc->sc_busdev = gpiobus_attach_bus(dev);
864 
865 	if (sc->sc_busdev == NULL) {
866 		imx51_gpio_detach(dev);
867 		return (ENXIO);
868 	}
869 
870 	return (0);
871 }
872 
873 static int
874 imx51_gpio_detach(device_t dev)
875 {
876 	int irq;
877 	struct imx51_gpio_softc *sc;
878 #ifdef IMX_ENABLE_CLOCKS
879 	int error;
880 #endif
881 
882 	sc = device_get_softc(dev);
883 
884 #ifdef IMX_ENABLE_CLOCKS
885 	error = clk_disable(sc->clk);
886 	if (error != 0) {
887 		device_printf(sc->dev, "could not disable ipg clock\n");
888 		return (error);
889 	}
890 #endif
891 
892 	gpiobus_detach_bus(dev);
893 	for (irq = 0; irq < NUM_IRQRES; irq++) {
894 		if (sc->gpio_ih[irq])
895 			bus_teardown_intr(dev, sc->sc_res[irq + FIRST_IRQRES],
896 			    sc->gpio_ih[irq]);
897 	}
898 	bus_release_resources(dev, imx_gpio_spec, sc->sc_res);
899 	mtx_destroy(&sc->sc_mtx);
900 
901 	return(0);
902 }
903 
904 static phandle_t
905 imx51_gpio_get_node(device_t bus, device_t dev)
906 {
907 	/*
908 	 * Share controller node with gpiobus device
909 	 */
910 	return ofw_bus_get_node(bus);
911 }
912 
913 static device_method_t imx51_gpio_methods[] = {
914 	DEVMETHOD(device_probe,		imx51_gpio_probe),
915 	DEVMETHOD(device_attach,	imx51_gpio_attach),
916 	DEVMETHOD(device_detach,	imx51_gpio_detach),
917 
918 #ifdef INTRNG
919 	/* Interrupt controller interface */
920 	DEVMETHOD(pic_disable_intr,	gpio_pic_disable_intr),
921 	DEVMETHOD(pic_enable_intr,	gpio_pic_enable_intr),
922 	DEVMETHOD(pic_map_intr,		gpio_pic_map_intr),
923 	DEVMETHOD(pic_setup_intr,	gpio_pic_setup_intr),
924 	DEVMETHOD(pic_teardown_intr,	gpio_pic_teardown_intr),
925 	DEVMETHOD(pic_post_filter,	gpio_pic_post_filter),
926 	DEVMETHOD(pic_post_ithread,	gpio_pic_post_ithread),
927 	DEVMETHOD(pic_pre_ithread,	gpio_pic_pre_ithread),
928 #endif
929 
930 	/* OFW methods */
931 	DEVMETHOD(ofw_bus_get_node,	imx51_gpio_get_node),
932 
933 	/* GPIO protocol */
934 	DEVMETHOD(gpio_get_bus,		imx51_gpio_get_bus),
935 	DEVMETHOD(gpio_pin_max,		imx51_gpio_pin_max),
936 	DEVMETHOD(gpio_pin_getname,	imx51_gpio_pin_getname),
937 	DEVMETHOD(gpio_pin_getflags,	imx51_gpio_pin_getflags),
938 	DEVMETHOD(gpio_pin_getcaps,	imx51_gpio_pin_getcaps),
939 	DEVMETHOD(gpio_pin_setflags,	imx51_gpio_pin_setflags),
940 	DEVMETHOD(gpio_pin_get,		imx51_gpio_pin_get),
941 	DEVMETHOD(gpio_pin_set,		imx51_gpio_pin_set),
942 	DEVMETHOD(gpio_pin_toggle,	imx51_gpio_pin_toggle),
943 	DEVMETHOD(gpio_pin_access_32,	imx51_gpio_pin_access_32),
944 	DEVMETHOD(gpio_pin_config_32,	imx51_gpio_pin_config_32),
945 	{0, 0},
946 };
947 
948 static driver_t imx51_gpio_driver = {
949 	"gpio",
950 	imx51_gpio_methods,
951 	sizeof(struct imx51_gpio_softc),
952 };
953 
954 EARLY_DRIVER_MODULE(imx51_gpio, simplebus, imx51_gpio_driver, 0, 0,
955     BUS_PASS_INTERRUPT + BUS_PASS_ORDER_LATE);
956