xref: /freebsd/sys/arm/freescale/imx/imx_gpio.c (revision 190cef3d)
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/gpio/gpiobusvar.h>
56 #include <dev/ofw/openfirm.h>
57 #include <dev/ofw/ofw_bus.h>
58 #include <dev/ofw/ofw_bus_subr.h>
59 
60 #include "gpio_if.h"
61 
62 #ifdef INTRNG
63 #include "pic_if.h"
64 #endif
65 
66 #define	WRITE4(_sc, _r, _v)						\
67 	    bus_space_write_4((_sc)->sc_iot, (_sc)->sc_ioh, (_r), (_v))
68 #define	READ4(_sc, _r)							\
69 	    bus_space_read_4((_sc)->sc_iot, (_sc)->sc_ioh, (_r))
70 #define	SET4(_sc, _r, _m)						\
71 	    WRITE4((_sc), (_r), READ4((_sc), (_r)) | (_m))
72 #define	CLEAR4(_sc, _r, _m)						\
73 	    WRITE4((_sc), (_r), READ4((_sc), (_r)) & ~(_m))
74 
75 /* Registers definition for Freescale i.MX515 GPIO controller */
76 
77 #define	IMX_GPIO_DR_REG		0x000 /* Pin Data */
78 #define	IMX_GPIO_OE_REG		0x004 /* Set Pin Output */
79 #define	IMX_GPIO_PSR_REG	0x008 /* Pad Status */
80 #define	IMX_GPIO_ICR1_REG	0x00C /* Interrupt Configuration */
81 #define	IMX_GPIO_ICR2_REG	0x010 /* Interrupt Configuration */
82 #define		GPIO_ICR_COND_LOW	0
83 #define		GPIO_ICR_COND_HIGH	1
84 #define		GPIO_ICR_COND_RISE	2
85 #define		GPIO_ICR_COND_FALL	3
86 #define		GPIO_ICR_COND_MASK	0x3
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 #ifdef INTRNG
92 #define	DEFAULT_CAPS	(GPIO_PIN_INPUT | GPIO_PIN_OUTPUT | \
93     GPIO_INTR_LEVEL_LOW | GPIO_INTR_LEVEL_HIGH | GPIO_INTR_EDGE_RISING | \
94     GPIO_INTR_EDGE_FALLING | GPIO_INTR_EDGE_BOTH)
95 #else
96 #define	DEFAULT_CAPS	(GPIO_PIN_INPUT | GPIO_PIN_OUTPUT)
97 #endif
98 
99 #define	NGPIO		32
100 
101 #ifdef INTRNG
102 struct gpio_irqsrc {
103 	struct intr_irqsrc	gi_isrc;
104 	u_int			gi_irq;
105 	uint32_t		gi_mode;
106 };
107 #endif
108 
109 struct imx51_gpio_softc {
110 	device_t		dev;
111 	device_t		sc_busdev;
112 	struct mtx		sc_mtx;
113 	struct resource		*sc_res[3]; /* 1 x mem, 2 x IRQ */
114 	void			*gpio_ih[2];
115 	bus_space_tag_t		sc_iot;
116 	bus_space_handle_t	sc_ioh;
117 	int			gpio_npins;
118 	struct gpio_pin		gpio_pins[NGPIO];
119 #ifdef INTRNG
120 	struct gpio_irqsrc 	gpio_pic_irqsrc[NGPIO];
121 #endif
122 };
123 
124 static struct ofw_compat_data compat_data[] = {
125 	{"fsl,imx6q-gpio",  1},
126 	{"fsl,imx53-gpio",  1},
127 	{"fsl,imx51-gpio",  1},
128 	{NULL,	            0}
129 };
130 
131 static struct resource_spec imx_gpio_spec[] = {
132 	{ SYS_RES_MEMORY,	0,	RF_ACTIVE },
133 	{ SYS_RES_IRQ,		0,	RF_ACTIVE },
134 	{ SYS_RES_IRQ,		1,	RF_ACTIVE },
135 	{ -1, 0 }
136 };
137 #define	FIRST_IRQRES	1
138 #define	NUM_IRQRES	2
139 
140 /*
141  * Helpers
142  */
143 static void imx51_gpio_pin_configure(struct imx51_gpio_softc *,
144     struct gpio_pin *, uint32_t);
145 
146 /*
147  * Driver stuff
148  */
149 static int imx51_gpio_probe(device_t);
150 static int imx51_gpio_attach(device_t);
151 static int imx51_gpio_detach(device_t);
152 
153 /*
154  * GPIO interface
155  */
156 static device_t imx51_gpio_get_bus(device_t);
157 static int imx51_gpio_pin_max(device_t, int *);
158 static int imx51_gpio_pin_getcaps(device_t, uint32_t, uint32_t *);
159 static int imx51_gpio_pin_getflags(device_t, uint32_t, uint32_t *);
160 static int imx51_gpio_pin_getname(device_t, uint32_t, char *);
161 static int imx51_gpio_pin_setflags(device_t, uint32_t, uint32_t);
162 static int imx51_gpio_pin_set(device_t, uint32_t, unsigned int);
163 static int imx51_gpio_pin_get(device_t, uint32_t, unsigned int *);
164 static int imx51_gpio_pin_toggle(device_t, uint32_t pin);
165 
166 #ifdef INTRNG
167 static int
168 gpio_pic_map_fdt(struct imx51_gpio_softc *sc, struct intr_map_data_fdt *daf,
169     u_int *irqp, uint32_t *modep)
170 {
171 	u_int irq;
172 	uint32_t mode;
173 
174 	/*
175 	 * From devicetree/bindings/gpio/fsl-imx-gpio.txt:
176 	 *  #interrupt-cells:  2. The first cell is the GPIO number. The second
177 	 *  cell bits[3:0] is used to specify trigger type and level flags:
178 	 *    1 = low-to-high edge triggered.
179 	 *    2 = high-to-low edge triggered.
180 	 *    4 = active high level-sensitive.
181 	 *    8 = active low level-sensitive.
182 	 * We can do any single one of these modes, and also edge low+high
183 	 * (i.e., trigger on both edges); other combinations are not supported.
184 	 */
185 
186 	if (daf->ncells != 2) {
187 		device_printf(sc->dev, "Invalid #interrupt-cells\n");
188 		return (EINVAL);
189 	}
190 
191 	irq = daf->cells[0];
192 	if (irq >= sc->gpio_npins) {
193 		device_printf(sc->dev, "Invalid interrupt number %u\n", irq);
194 		return (EINVAL);
195 	}
196 	switch (daf->cells[1]) {
197 	case 1:
198 		mode = GPIO_INTR_EDGE_RISING;
199 		break;
200 	case 2:
201 		mode = GPIO_INTR_EDGE_FALLING;
202 		break;
203 	case 3:
204 		mode = GPIO_INTR_EDGE_BOTH;
205 		break;
206 	case 4:
207 		mode = GPIO_INTR_LEVEL_HIGH;
208 		break;
209 	case 8:
210 		mode = GPIO_INTR_LEVEL_LOW;
211 		break;
212 	default:
213 		device_printf(sc->dev, "Unsupported interrupt mode 0x%2x\n",
214 		    daf->cells[1]);
215 		return (ENOTSUP);
216 	}
217 	*irqp = irq;
218 	if (modep != NULL)
219 		*modep = mode;
220 	return (0);
221 }
222 
223 static int
224 gpio_pic_map_gpio(struct imx51_gpio_softc *sc, struct intr_map_data_gpio *dag,
225     u_int *irqp, uint32_t *modep)
226 {
227 	u_int irq;
228 
229 	irq = dag->gpio_pin_num;
230 	if (irq >= sc->gpio_npins) {
231 		device_printf(sc->dev, "Invalid interrupt number %u\n", irq);
232 		return (EINVAL);
233 	}
234 
235 	switch (dag->gpio_intr_mode) {
236 	case GPIO_INTR_LEVEL_LOW:
237 	case GPIO_INTR_LEVEL_HIGH:
238 	case GPIO_INTR_EDGE_RISING:
239 	case GPIO_INTR_EDGE_FALLING:
240 	case GPIO_INTR_EDGE_BOTH:
241 		break;
242 	default:
243 		device_printf(sc->dev, "Unsupported interrupt mode 0x%8x\n",
244 		    dag->gpio_intr_mode);
245 		return (EINVAL);
246 	}
247 
248 	*irqp = irq;
249 	if (modep != NULL)
250 		*modep = dag->gpio_intr_mode;
251 	return (0);
252 }
253 
254 static int
255 gpio_pic_map(struct imx51_gpio_softc *sc, struct intr_map_data *data,
256     u_int *irqp, uint32_t *modep)
257 {
258 
259 	switch (data->type) {
260 	case INTR_MAP_DATA_FDT:
261 		return (gpio_pic_map_fdt(sc, (struct intr_map_data_fdt *)data,
262 		    irqp, modep));
263 	case INTR_MAP_DATA_GPIO:
264 		return (gpio_pic_map_gpio(sc, (struct intr_map_data_gpio *)data,
265 		    irqp, modep));
266 	default:
267 		return (ENOTSUP);
268 	}
269 }
270 
271 static int
272 gpio_pic_map_intr(device_t dev, struct intr_map_data *data,
273     struct intr_irqsrc **isrcp)
274 {
275 	int error;
276 	u_int irq;
277 	struct imx51_gpio_softc *sc;
278 
279 	sc = device_get_softc(dev);
280 	error = gpio_pic_map(sc, data, &irq, NULL);
281 	if (error == 0)
282 		*isrcp = &sc->gpio_pic_irqsrc[irq].gi_isrc;
283 	return (error);
284 }
285 
286 static int
287 gpio_pic_teardown_intr(device_t dev, struct intr_irqsrc *isrc,
288     struct resource *res, struct intr_map_data *data)
289 {
290 	struct imx51_gpio_softc *sc;
291 	struct gpio_irqsrc *gi;
292 
293 	sc = device_get_softc(dev);
294 	if (isrc->isrc_handlers == 0) {
295 		gi = (struct gpio_irqsrc *)isrc;
296 		gi->gi_mode = GPIO_INTR_CONFORM;
297 
298 		// XXX Not sure this is necessary
299 		mtx_lock_spin(&sc->sc_mtx);
300 		CLEAR4(sc, IMX_GPIO_IMR_REG, (1U << gi->gi_irq));
301 		WRITE4(sc, IMX_GPIO_ISR_REG, (1U << gi->gi_irq));
302 		mtx_unlock_spin(&sc->sc_mtx);
303 	}
304 	return (0);
305 }
306 
307 static int
308 gpio_pic_setup_intr(device_t dev, struct intr_irqsrc *isrc,
309     struct resource *res, struct intr_map_data *data)
310 {
311 	struct imx51_gpio_softc *sc;
312 	struct gpio_irqsrc *gi;
313 	int error;
314 	u_int icfg, irq, reg, shift, wrk;
315 	uint32_t mode;
316 
317 	if (data == NULL)
318 		return (ENOTSUP);
319 
320 	sc = device_get_softc(dev);
321 	gi = (struct gpio_irqsrc *)isrc;
322 
323 	/* Get config for interrupt. */
324 	error = gpio_pic_map(sc, data, &irq, &mode);
325 	if (error != 0)
326 		return (error);
327 	if (gi->gi_irq != irq)
328 		return (EINVAL);
329 
330 	/* Compare config if this is not first setup. */
331 	if (isrc->isrc_handlers != 0)
332 		return (gi->gi_mode == mode ? 0 : EINVAL);
333 	gi->gi_mode = mode;
334 
335 	/*
336 	 * To interrupt on both edges we have to use the EDGE register.  The
337 	 * manual says it only exists for backwards compatibilty with older imx
338 	 * chips, but it's also the only way to configure interrupting on both
339 	 * edges.  If the EDGE bit is on, the corresponding ICRn bit is ignored.
340 	 */
341 	mtx_lock_spin(&sc->sc_mtx);
342 	if (mode == GPIO_INTR_EDGE_BOTH) {
343 		SET4(sc, IMX_GPIO_EDGE_REG, (1u << irq));
344 	} else {
345 		CLEAR4(sc, IMX_GPIO_EDGE_REG, (1u << irq));
346 		switch (mode) {
347 		default:
348 			/* silence warnings; default can't actually happen. */
349 			/* FALLTHROUGH */
350 		case GPIO_INTR_LEVEL_LOW:
351 			icfg = GPIO_ICR_COND_LOW;
352 			break;
353 		case GPIO_INTR_LEVEL_HIGH:
354 			icfg = GPIO_ICR_COND_HIGH;
355 			break;
356 		case GPIO_INTR_EDGE_RISING:
357 			icfg = GPIO_ICR_COND_RISE;
358 			break;
359 		case GPIO_INTR_EDGE_FALLING:
360 			icfg = GPIO_ICR_COND_FALL;
361 			break;
362 		}
363 		if (irq < 16) {
364 			reg = IMX_GPIO_ICR1_REG;
365 			shift = 2 * irq;
366 		} else {
367 			reg = IMX_GPIO_ICR2_REG;
368 			shift = 2 * (irq - 16);
369 		}
370 		wrk = READ4(sc, reg);
371 		wrk &= ~(GPIO_ICR_COND_MASK << shift);
372 		wrk |= icfg << shift;
373 		WRITE4(sc, reg, wrk);
374 	}
375 	WRITE4(sc, IMX_GPIO_ISR_REG, (1u << irq));
376 	SET4(sc, IMX_GPIO_IMR_REG, (1u << irq));
377 	mtx_unlock_spin(&sc->sc_mtx);
378 
379 	return (0);
380 }
381 
382 /*
383  * this is mask_intr
384  */
385 static void
386 gpio_pic_disable_intr(device_t dev, struct intr_irqsrc *isrc)
387 {
388 	struct imx51_gpio_softc *sc;
389 	u_int irq;
390 
391 	sc = device_get_softc(dev);
392 	irq = ((struct gpio_irqsrc *)isrc)->gi_irq;
393 
394 	mtx_lock_spin(&sc->sc_mtx);
395 	CLEAR4(sc, IMX_GPIO_IMR_REG, (1U << irq));
396 	mtx_unlock_spin(&sc->sc_mtx);
397 }
398 
399 /*
400  * this is unmask_intr
401  */
402 static void
403 gpio_pic_enable_intr(device_t dev, struct intr_irqsrc *isrc)
404 {
405 	struct imx51_gpio_softc *sc;
406 	u_int irq;
407 
408 	sc = device_get_softc(dev);
409 	irq = ((struct gpio_irqsrc *)isrc)->gi_irq;
410 
411 	mtx_lock_spin(&sc->sc_mtx);
412 	SET4(sc, IMX_GPIO_IMR_REG, (1U << irq));
413 	mtx_unlock_spin(&sc->sc_mtx);
414 }
415 
416 static void
417 gpio_pic_post_filter(device_t dev, struct intr_irqsrc *isrc)
418 {
419 	struct imx51_gpio_softc *sc;
420 	u_int irq;
421 
422 	sc = device_get_softc(dev);
423 	irq = ((struct gpio_irqsrc *)isrc)->gi_irq;
424 
425 	arm_irq_memory_barrier(0);
426         /* EOI.  W1C reg so no r-m-w, no locking needed. */
427 	WRITE4(sc, IMX_GPIO_ISR_REG, (1U << irq));
428 }
429 
430 static void
431 gpio_pic_post_ithread(device_t dev, struct intr_irqsrc *isrc)
432 {
433 	struct imx51_gpio_softc *sc;
434 	u_int irq;
435 
436 	sc = device_get_softc(dev);
437 	irq = ((struct gpio_irqsrc *)isrc)->gi_irq;
438 
439 	arm_irq_memory_barrier(0);
440 	/* EOI.  W1C reg so no r-m-w, no locking needed. */
441 	WRITE4(sc, IMX_GPIO_ISR_REG, (1U << irq));
442 	gpio_pic_enable_intr(dev, isrc);
443 }
444 
445 static void
446 gpio_pic_pre_ithread(device_t dev, struct intr_irqsrc *isrc)
447 {
448 	gpio_pic_disable_intr(dev, isrc);
449 }
450 
451 static int
452 gpio_pic_filter(void *arg)
453 {
454 	struct imx51_gpio_softc *sc;
455 	struct intr_irqsrc *isrc;
456 	uint32_t i, interrupts;
457 
458 	sc = arg;
459 	mtx_lock_spin(&sc->sc_mtx);
460 	interrupts = READ4(sc, IMX_GPIO_ISR_REG) & READ4(sc, IMX_GPIO_IMR_REG);
461 	mtx_unlock_spin(&sc->sc_mtx);
462 
463 	for (i = 0; interrupts != 0; i++, interrupts >>= 1) {
464 		if ((interrupts & 0x1) == 0)
465 			continue;
466 		isrc = &sc->gpio_pic_irqsrc[i].gi_isrc;
467 		if (intr_isrc_dispatch(isrc, curthread->td_intr_frame) != 0) {
468 			gpio_pic_disable_intr(sc->dev, isrc);
469 			gpio_pic_post_filter(sc->dev, isrc);
470 			device_printf(sc->dev, "Stray irq %u disabled\n", i);
471 		}
472 	}
473 
474 	return (FILTER_HANDLED);
475 }
476 
477 /*
478  * Initialize our isrcs and register them with intrng.
479  */
480 static int
481 gpio_pic_register_isrcs(struct imx51_gpio_softc *sc)
482 {
483 	int error;
484 	uint32_t irq;
485 	const char *name;
486 
487 	name = device_get_nameunit(sc->dev);
488 	for (irq = 0; irq < NGPIO; irq++) {
489 		sc->gpio_pic_irqsrc[irq].gi_irq = irq;
490 		sc->gpio_pic_irqsrc[irq].gi_mode = GPIO_INTR_CONFORM;
491 
492 		error = intr_isrc_register(&sc->gpio_pic_irqsrc[irq].gi_isrc,
493 		    sc->dev, 0, "%s,%u", name, irq);
494 		if (error != 0) {
495 			/* XXX call intr_isrc_deregister() */
496 			device_printf(sc->dev, "%s failed", __func__);
497 			return (error);
498 		}
499 	}
500 	return (0);
501 }
502 #endif
503 
504 /*
505  *
506  */
507 static void
508 imx51_gpio_pin_configure(struct imx51_gpio_softc *sc, struct gpio_pin *pin,
509     unsigned int flags)
510 {
511 	u_int newflags, pad;
512 
513 	mtx_lock_spin(&sc->sc_mtx);
514 
515 	/*
516 	 * Manage input/output; other flags not supported yet (maybe not ever,
517 	 * since we have no connection to the pad config registers from here).
518 	 *
519 	 * When setting a pin to output, honor the PRESET_[LOW,HIGH] flags if
520 	 * present.  Otherwise, for glitchless transistions on pins with pulls,
521 	 * read the current state of the pad and preset the DR register to drive
522 	 * the current value onto the pin before enabling the pin for output.
523 	 *
524 	 * Note that changes to pin->gp_flags must be acccumulated in newflags
525 	 * and stored with a single writeback to gp_flags at the end, to enable
526 	 * unlocked reads of that value elsewhere. This is only about unlocked
527 	 * access to gp_flags from elsewhere; we still use locking in this
528 	 * function to protect r-m-w access to the hardware registers.
529 	 */
530 	if (flags & (GPIO_PIN_INPUT | GPIO_PIN_OUTPUT)) {
531 		newflags = pin->gp_flags & ~(GPIO_PIN_INPUT | GPIO_PIN_OUTPUT);
532 		if (flags & GPIO_PIN_OUTPUT) {
533 			if (flags & GPIO_PIN_PRESET_LOW) {
534 				pad = 0;
535 			} else if (flags & GPIO_PIN_PRESET_HIGH) {
536 				pad = 1;
537 			} else {
538 				if (flags & GPIO_PIN_OPENDRAIN)
539 					pad = READ4(sc, IMX_GPIO_PSR_REG);
540 				else
541 					pad = READ4(sc, IMX_GPIO_DR_REG);
542 				pad = (pad >> pin->gp_pin) & 1;
543 			}
544 			newflags |= GPIO_PIN_OUTPUT;
545 			SET4(sc, IMX_GPIO_DR_REG, (pad << pin->gp_pin));
546 			SET4(sc, IMX_GPIO_OE_REG, (1U << pin->gp_pin));
547 		} else {
548 			newflags |= GPIO_PIN_INPUT;
549 			CLEAR4(sc, IMX_GPIO_OE_REG, (1U << pin->gp_pin));
550 		}
551 		pin->gp_flags = newflags;
552 	}
553 
554 	mtx_unlock_spin(&sc->sc_mtx);
555 }
556 
557 static device_t
558 imx51_gpio_get_bus(device_t dev)
559 {
560 	struct imx51_gpio_softc *sc;
561 
562 	sc = device_get_softc(dev);
563 
564 	return (sc->sc_busdev);
565 }
566 
567 static int
568 imx51_gpio_pin_max(device_t dev, int *maxpin)
569 {
570 	struct imx51_gpio_softc *sc;
571 
572 	sc = device_get_softc(dev);
573 	*maxpin = sc->gpio_npins - 1;
574 
575 	return (0);
576 }
577 
578 static int
579 imx51_gpio_pin_getcaps(device_t dev, uint32_t pin, uint32_t *caps)
580 {
581 	struct imx51_gpio_softc *sc;
582 
583 	sc = device_get_softc(dev);
584 
585 	if (pin >= sc->gpio_npins)
586 		return (EINVAL);
587 
588 	*caps = sc->gpio_pins[pin].gp_caps;
589 
590 	return (0);
591 }
592 
593 static int
594 imx51_gpio_pin_getflags(device_t dev, uint32_t pin, uint32_t *flags)
595 {
596 	struct imx51_gpio_softc *sc;
597 
598 	sc = device_get_softc(dev);
599 
600 	if (pin >= sc->gpio_npins)
601 		return (EINVAL);
602 
603 	*flags = sc->gpio_pins[pin].gp_flags;
604 
605 	return (0);
606 }
607 
608 static int
609 imx51_gpio_pin_getname(device_t dev, uint32_t pin, char *name)
610 {
611 	struct imx51_gpio_softc *sc;
612 
613 	sc = device_get_softc(dev);
614 	if (pin >= sc->gpio_npins)
615 		return (EINVAL);
616 
617 	mtx_lock_spin(&sc->sc_mtx);
618 	memcpy(name, sc->gpio_pins[pin].gp_name, GPIOMAXNAME);
619 	mtx_unlock_spin(&sc->sc_mtx);
620 
621 	return (0);
622 }
623 
624 static int
625 imx51_gpio_pin_setflags(device_t dev, uint32_t pin, uint32_t flags)
626 {
627 	struct imx51_gpio_softc *sc;
628 
629 	sc = device_get_softc(dev);
630 
631 	if (pin >= sc->gpio_npins)
632 		return (EINVAL);
633 
634 	imx51_gpio_pin_configure(sc, &sc->gpio_pins[pin], flags);
635 
636 	return (0);
637 }
638 
639 static int
640 imx51_gpio_pin_set(device_t dev, uint32_t pin, unsigned int value)
641 {
642 	struct imx51_gpio_softc *sc;
643 
644 	sc = device_get_softc(dev);
645 
646 	if (pin >= sc->gpio_npins)
647 		return (EINVAL);
648 
649 	mtx_lock_spin(&sc->sc_mtx);
650 	if (value)
651 		SET4(sc, IMX_GPIO_DR_REG, (1U << pin));
652 	else
653 		CLEAR4(sc, IMX_GPIO_DR_REG, (1U << pin));
654 	mtx_unlock_spin(&sc->sc_mtx);
655 
656 	return (0);
657 }
658 
659 static int
660 imx51_gpio_pin_get(device_t dev, uint32_t pin, unsigned int *val)
661 {
662 	struct imx51_gpio_softc *sc;
663 
664 	sc = device_get_softc(dev);
665 
666 	if (pin >= sc->gpio_npins)
667 		return (EINVAL);
668 
669 	/*
670 	 * Normally a pin set for output can be read by reading the DR reg which
671 	 * indicates what value is being driven to that pin.  The exception is
672 	 * pins configured for open-drain mode, in which case we have to read
673 	 * the pad status register in case the pin is being driven externally.
674 	 * Doing so requires that the SION bit be configured in pinmux, which
675 	 * isn't the case for most normal gpio pins, so only try to read via PSR
676 	 * if the OPENDRAIN flag is set, and it's the user's job to correctly
677 	 * configure SION along with open-drain output mode for those pins.
678 	 */
679 	if (sc->gpio_pins[pin].gp_flags & GPIO_PIN_OPENDRAIN)
680 		*val = (READ4(sc, IMX_GPIO_PSR_REG) >> pin) & 1;
681 	else
682 		*val = (READ4(sc, IMX_GPIO_DR_REG) >> pin) & 1;
683 
684 	return (0);
685 }
686 
687 static int
688 imx51_gpio_pin_toggle(device_t dev, uint32_t pin)
689 {
690 	struct imx51_gpio_softc *sc;
691 
692 	sc = device_get_softc(dev);
693 
694 	if (pin >= sc->gpio_npins)
695 		return (EINVAL);
696 
697 	mtx_lock_spin(&sc->sc_mtx);
698 	WRITE4(sc, IMX_GPIO_DR_REG,
699 	    (READ4(sc, IMX_GPIO_DR_REG) ^ (1U << pin)));
700 	mtx_unlock_spin(&sc->sc_mtx);
701 
702 	return (0);
703 }
704 
705 static int
706 imx51_gpio_pin_access_32(device_t dev, uint32_t first_pin, uint32_t clear_pins,
707     uint32_t change_pins, uint32_t *orig_pins)
708 {
709 	struct imx51_gpio_softc *sc;
710 
711 	if (first_pin != 0)
712 		return (EINVAL);
713 
714 	sc = device_get_softc(dev);
715 
716 	if (orig_pins != NULL)
717 		*orig_pins = READ4(sc, IMX_GPIO_DR_REG);
718 
719 	if ((clear_pins | change_pins) != 0) {
720 		mtx_lock_spin(&sc->sc_mtx);
721 		WRITE4(sc, IMX_GPIO_DR_REG,
722 		    (READ4(sc, IMX_GPIO_DR_REG) & ~clear_pins) ^ change_pins);
723 		mtx_unlock_spin(&sc->sc_mtx);
724 	}
725 
726 	return (0);
727 }
728 
729 static int
730 imx51_gpio_pin_config_32(device_t dev, uint32_t first_pin, uint32_t num_pins,
731     uint32_t *pin_flags)
732 {
733 	struct imx51_gpio_softc *sc;
734 	u_int i;
735 	uint32_t bit, drclr, drset, flags, oeclr, oeset, pads;
736 
737 	sc = device_get_softc(dev);
738 
739 	if (first_pin != 0 || num_pins > sc->gpio_npins)
740 		return (EINVAL);
741 
742 	drclr = drset = oeclr = oeset = 0;
743 	pads = READ4(sc, IMX_GPIO_DR_REG);
744 
745 	for (i = 0; i < num_pins; ++i) {
746 		bit = 1u << i;
747 		flags = pin_flags[i];
748 		if (flags & GPIO_PIN_INPUT) {
749 			oeclr |= bit;
750 		} else if (flags & GPIO_PIN_OUTPUT) {
751 			oeset |= bit;
752 			if (flags & GPIO_PIN_PRESET_LOW)
753 				drclr |= bit;
754 			else if (flags & GPIO_PIN_PRESET_HIGH)
755 				drset |= bit;
756 			else /* Drive whatever it's now pulled to. */
757 				drset |= pads & bit;
758 		}
759 	}
760 
761 	mtx_lock_spin(&sc->sc_mtx);
762 	WRITE4(sc, IMX_GPIO_DR_REG,
763 	    (READ4(sc, IMX_GPIO_DR_REG) & ~drclr) | drset);
764 	WRITE4(sc, IMX_GPIO_OE_REG,
765 	    (READ4(sc, IMX_GPIO_OE_REG) & ~oeclr) | oeset);
766 	mtx_unlock_spin(&sc->sc_mtx);
767 
768 	return (0);
769 }
770 
771 static int
772 imx51_gpio_probe(device_t dev)
773 {
774 
775 	if (!ofw_bus_status_okay(dev))
776 		return (ENXIO);
777 
778 	if (ofw_bus_search_compatible(dev, compat_data)->ocd_data != 0) {
779 		device_set_desc(dev, "Freescale i.MX GPIO Controller");
780 		return (BUS_PROBE_DEFAULT);
781 	}
782 
783 	return (ENXIO);
784 }
785 
786 static int
787 imx51_gpio_attach(device_t dev)
788 {
789 	struct imx51_gpio_softc *sc;
790 	int i, irq, unit;
791 
792 	sc = device_get_softc(dev);
793 	sc->dev = dev;
794 	sc->gpio_npins = NGPIO;
795 
796 	mtx_init(&sc->sc_mtx, device_get_nameunit(sc->dev), NULL, MTX_SPIN);
797 
798 	if (bus_alloc_resources(dev, imx_gpio_spec, sc->sc_res)) {
799 		device_printf(dev, "could not allocate resources\n");
800 		bus_release_resources(dev, imx_gpio_spec, sc->sc_res);
801 		mtx_destroy(&sc->sc_mtx);
802 		return (ENXIO);
803 	}
804 
805 	sc->sc_iot = rman_get_bustag(sc->sc_res[0]);
806 	sc->sc_ioh = rman_get_bushandle(sc->sc_res[0]);
807 	/*
808 	 * Mask off all interrupts in hardware, then set up interrupt handling.
809 	 */
810 	WRITE4(sc, IMX_GPIO_IMR_REG, 0);
811 	for (irq = 0; irq < 2; irq++) {
812 #ifdef INTRNG
813 		if ((bus_setup_intr(dev, sc->sc_res[1 + irq], INTR_TYPE_CLK,
814 		    gpio_pic_filter, NULL, sc, &sc->gpio_ih[irq]))) {
815 			device_printf(dev,
816 			    "WARNING: unable to register interrupt handler\n");
817 			imx51_gpio_detach(dev);
818 			return (ENXIO);
819 		}
820 #endif
821 	}
822 
823 	unit = device_get_unit(dev);
824 	for (i = 0; i < sc->gpio_npins; i++) {
825  		sc->gpio_pins[i].gp_pin = i;
826  		sc->gpio_pins[i].gp_caps = DEFAULT_CAPS;
827  		sc->gpio_pins[i].gp_flags =
828  		    (READ4(sc, IMX_GPIO_OE_REG) & (1U << i)) ? GPIO_PIN_OUTPUT :
829  		    GPIO_PIN_INPUT;
830  		snprintf(sc->gpio_pins[i].gp_name, GPIOMAXNAME,
831  		    "GPIO%d_IO%02d", unit + 1, i);
832 	}
833 
834 #ifdef INTRNG
835 	gpio_pic_register_isrcs(sc);
836 	intr_pic_register(dev, OF_xref_from_node(ofw_bus_get_node(dev)));
837 #endif
838 	sc->sc_busdev = gpiobus_attach_bus(dev);
839 
840 	if (sc->sc_busdev == NULL) {
841 		imx51_gpio_detach(dev);
842 		return (ENXIO);
843 	}
844 
845 	return (0);
846 }
847 
848 static int
849 imx51_gpio_detach(device_t dev)
850 {
851 	int irq;
852 	struct imx51_gpio_softc *sc;
853 
854 	sc = device_get_softc(dev);
855 
856 	gpiobus_detach_bus(dev);
857 	for (irq = 0; irq < NUM_IRQRES; irq++) {
858 		if (sc->gpio_ih[irq])
859 			bus_teardown_intr(dev, sc->sc_res[irq + FIRST_IRQRES],
860 			    sc->gpio_ih[irq]);
861 	}
862 	bus_release_resources(dev, imx_gpio_spec, sc->sc_res);
863 	mtx_destroy(&sc->sc_mtx);
864 
865 	return(0);
866 }
867 
868 static device_method_t imx51_gpio_methods[] = {
869 	DEVMETHOD(device_probe,		imx51_gpio_probe),
870 	DEVMETHOD(device_attach,	imx51_gpio_attach),
871 	DEVMETHOD(device_detach,	imx51_gpio_detach),
872 
873 #ifdef INTRNG
874 	/* Interrupt controller interface */
875 	DEVMETHOD(pic_disable_intr,	gpio_pic_disable_intr),
876 	DEVMETHOD(pic_enable_intr,	gpio_pic_enable_intr),
877 	DEVMETHOD(pic_map_intr,		gpio_pic_map_intr),
878 	DEVMETHOD(pic_setup_intr,	gpio_pic_setup_intr),
879 	DEVMETHOD(pic_teardown_intr,	gpio_pic_teardown_intr),
880 	DEVMETHOD(pic_post_filter,	gpio_pic_post_filter),
881 	DEVMETHOD(pic_post_ithread,	gpio_pic_post_ithread),
882 	DEVMETHOD(pic_pre_ithread,	gpio_pic_pre_ithread),
883 #endif
884 
885 	/* GPIO protocol */
886 	DEVMETHOD(gpio_get_bus,		imx51_gpio_get_bus),
887 	DEVMETHOD(gpio_pin_max,		imx51_gpio_pin_max),
888 	DEVMETHOD(gpio_pin_getname,	imx51_gpio_pin_getname),
889 	DEVMETHOD(gpio_pin_getflags,	imx51_gpio_pin_getflags),
890 	DEVMETHOD(gpio_pin_getcaps,	imx51_gpio_pin_getcaps),
891 	DEVMETHOD(gpio_pin_setflags,	imx51_gpio_pin_setflags),
892 	DEVMETHOD(gpio_pin_get,		imx51_gpio_pin_get),
893 	DEVMETHOD(gpio_pin_set,		imx51_gpio_pin_set),
894 	DEVMETHOD(gpio_pin_toggle,	imx51_gpio_pin_toggle),
895 	DEVMETHOD(gpio_pin_access_32,	imx51_gpio_pin_access_32),
896 	DEVMETHOD(gpio_pin_config_32,	imx51_gpio_pin_config_32),
897 	{0, 0},
898 };
899 
900 static driver_t imx51_gpio_driver = {
901 	"gpio",
902 	imx51_gpio_methods,
903 	sizeof(struct imx51_gpio_softc),
904 };
905 static devclass_t imx51_gpio_devclass;
906 
907 EARLY_DRIVER_MODULE(imx51_gpio, simplebus, imx51_gpio_driver,
908     imx51_gpio_devclass, 0, 0, BUS_PASS_INTERRUPT + BUS_PASS_ORDER_LATE);
909