xref: /netbsd-src/sys/arch/arm/broadcom/bcm2835_gpio.c (revision f3cfa6f6ce31685c6c4a758bc430e69eb99f50a4)
1 /*	$NetBSD: bcm2835_gpio.c,v 1.12 2019/05/10 08:28:50 skrll Exp $	*/
2 
3 /*-
4  * Copyright (c) 2013, 2014, 2017 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Jonathan A. Kollasch, Frank Kardel and Nick Hudson
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
23  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
24  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
25  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
26  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
27  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
28  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
29  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 __KERNEL_RCSID(0, "$NetBSD: bcm2835_gpio.c,v 1.12 2019/05/10 08:28:50 skrll Exp $");
34 
35 /*
36  * Driver for BCM2835 GPIO
37  *
38  * see: http://www.raspberrypi.org/wp-content/uploads/2012/02/BCM2835-ARM-Peripherals.pdf
39  */
40 
41 #include <sys/param.h>
42 #include <sys/device.h>
43 #include <sys/systm.h>
44 #include <sys/mutex.h>
45 #include <sys/bus.h>
46 #include <sys/intr.h>
47 #include <sys/kernel.h>
48 #include <sys/kmem.h>
49 #include <sys/proc.h>
50 #include <sys/gpio.h>
51 
52 #include <sys/bitops.h>
53 
54 #include <arm/broadcom/bcm2835reg.h>
55 #include <arm/broadcom/bcm2835_gpioreg.h>
56 
57 #include <dev/gpio/gpiovar.h>
58 #include <dev/fdt/fdtvar.h>
59 
60 /* #define BCM2835_GPIO_DEBUG */
61 #ifdef BCM2835_GPIO_DEBUG
62 int bcm2835gpiodebug = 3;
63 #define DPRINTF(l, x)	do { if (l <= bcm2835gpiodebug) { printf x; } } while (0)
64 #else
65 #define DPRINTF(l, x)
66 #endif
67 
68 #define	BCMGPIO_MAXPINS	54
69 
70 struct bcmgpio_eint {
71 	 int			(*eint_func)(void *);
72 	 void			*eint_arg;
73 	 int			eint_flags;
74 	 int			eint_bank;
75 	 int			eint_num;
76 };
77 
78 #define	BCMGPIO_INTR_POS_EDGE	0x01
79 #define	BCMGPIO_INTR_NEG_EDGE	0x02
80 #define	BCMGPIO_INTR_HIGH_LEVEL	0x04
81 #define	BCMGPIO_INTR_LOW_LEVEL	0x08
82 #define	BCMGPIO_INTR_MPSAFE	0x10
83 
84 struct bcmgpio_softc;
85 struct bcmgpio_bank {
86 	struct bcmgpio_softc	*sc_bcm;
87 	void			*sc_ih;
88 	struct bcmgpio_eint	sc_eint[32];
89 	int			sc_bankno;
90 };
91 #define	BCMGPIO_NBANKS	2
92 
93 struct bcmgpio_softc {
94 	device_t		sc_dev;
95 	bus_space_tag_t		sc_iot;
96 	bus_space_handle_t	sc_ioh;
97 	struct gpio_chipset_tag	sc_gpio_gc;
98 
99 	kmutex_t		sc_lock;
100 	gpio_pin_t		sc_gpio_pins[BCMGPIO_MAXPINS];
101 
102 	/* For interrupt support. */
103 	struct bcmgpio_bank	sc_banks[BCMGPIO_NBANKS];
104 };
105 
106 struct bcmgpio_pin {
107 	int			pin_no;
108 	u_int			pin_flags;
109 	bool			pin_actlo;
110 };
111 
112 
113 static int	bcmgpio_match(device_t, cfdata_t, void *);
114 static void	bcmgpio_attach(device_t, device_t, void *);
115 
116 static int	bcm2835gpio_gpio_pin_read(void *, int);
117 static void	bcm2835gpio_gpio_pin_write(void *, int, int);
118 static void	bcm2835gpio_gpio_pin_ctl(void *, int, int);
119 
120 static void *	bcmgpio_gpio_intr_establish(void *, int, int, int,
121 					    int (*)(void *), void *);
122 static void	bcmgpio_gpio_intr_disestablish(void *, void *);
123 static bool	bcmgpio_gpio_intrstr(void *, int, int, char *, size_t);
124 
125 static int	bcmgpio_intr(void *);
126 
127 u_int		bcm283x_pin_getfunc(const struct bcmgpio_softc * const, u_int);
128 void		bcm283x_pin_setfunc(const struct bcmgpio_softc * const, u_int,
129 		    u_int);
130 void		bcm283x_pin_setpull(const struct bcmgpio_softc * const, u_int,
131 		    u_int);
132 
133 static int 	bcm283x_pinctrl_set_config(device_t, const void *, size_t);
134 
135 static void *	bcmgpio_fdt_acquire(device_t, const void *, size_t, int);
136 static void	bcmgpio_fdt_release(device_t, void *);
137 static int	bcmgpio_fdt_read(device_t, void *, bool);
138 static void	bcmgpio_fdt_write(device_t, void *, int, bool);
139 
140 static struct fdtbus_gpio_controller_func bcmgpio_funcs = {
141 	.acquire = bcmgpio_fdt_acquire,
142 	.release = bcmgpio_fdt_release,
143 	.read = bcmgpio_fdt_read,
144 	.write = bcmgpio_fdt_write
145 };
146 
147 static void *	bcmgpio_fdt_intr_establish(device_t, u_int *, int, int,
148 		    int (*func)(void *), void *);
149 static void	bcmgpio_fdt_intr_disestablish(device_t, void *);
150 static bool	bcmgpio_fdt_intrstr(device_t, u_int *, char *, size_t);
151 
152 static struct fdtbus_interrupt_controller_func bcmgpio_fdt_intrfuncs = {
153 	.establish = bcmgpio_fdt_intr_establish,
154 	.disestablish = bcmgpio_fdt_intr_disestablish,
155 	.intrstr = bcmgpio_fdt_intrstr,
156 };
157 
158 CFATTACH_DECL_NEW(bcmgpio, sizeof(struct bcmgpio_softc),
159     bcmgpio_match, bcmgpio_attach, NULL, NULL);
160 
161 
162 static struct fdtbus_pinctrl_controller_func bcm283x_pinctrl_funcs = {
163 	.set_config = bcm283x_pinctrl_set_config,
164 };
165 
166 static int
167 bcm283x_pinctrl_set_config(device_t dev, const void *data, size_t len)
168 {
169 	struct bcmgpio_softc * const sc = device_private(dev);
170 
171 	if (len != 4)
172 		return -1;
173 
174 	const int phandle = fdtbus_get_phandle_from_native(be32dec(data));
175 
176 	/*
177 	 * Required: brcm,pins
178 	 * Optional: brcm,function, brcm,pull
179 	 */
180 
181 	int pins_len;
182 	const u_int *pins = fdtbus_get_prop(phandle, "brcm,pins", &pins_len);
183 
184 	if (pins == NULL)
185 		return -1;
186 
187 	int pull_len = 0;
188 	const u_int *pull = fdtbus_get_prop(phandle, "brcm,pull", &pull_len);
189 
190 	int func_len = 0;
191 	const u_int *func = fdtbus_get_prop(phandle, "brcm,function", &func_len);
192 
193 	if (!pull && !func) {
194 		aprint_error_dev(dev, "one of brcm,pull or brcm,funcion must "
195 		    "be specified");
196 		return -1;
197 	}
198 
199 	const int npins = pins_len / 4;
200 	const int npull = pull_len / 4;
201 	const int nfunc = func_len / 4;
202 
203 	if (npull > 1 && npull != npins) {
204 		aprint_error_dev(dev, "brcm,pull must have 1 or %d entries",
205 		    npins);
206 		return -1;
207 	}
208 	if (nfunc > 1 && nfunc != npins) {
209 		aprint_error_dev(dev, "brcm,function must have 1 or %d entries",
210 		    npins);
211 		return -1;
212 	}
213 
214 	mutex_enter(&sc->sc_lock);
215 
216 	for (int i = 0; i < npins; i++) {
217 		const u_int pin = be32toh(pins[i]);
218 
219 		if (pin > BCMGPIO_MAXPINS)
220 			continue;
221 		if (pull) {
222 			const int value = be32toh(pull[npull == 1 ? 0 : i]);
223 			bcm283x_pin_setpull(sc, pin, value);
224 		}
225 		if (func) {
226 			const int value = be32toh(func[nfunc == 1 ? 0 : i]);
227 			bcm283x_pin_setfunc(sc, pin, value);
228 		}
229 	}
230 
231 	mutex_exit(&sc->sc_lock);
232 
233 	return 0;
234 }
235 
236 static int
237 bcmgpio_match(device_t parent, cfdata_t cf, void *aux)
238 {
239 	const char * const compatible[] = { "brcm,bcm2835-gpio", NULL };
240 	struct fdt_attach_args * const faa = aux;
241 
242 	return of_match_compatible(faa->faa_phandle, compatible);
243 }
244 
245 static void
246 bcmgpio_attach(device_t parent, device_t self, void *aux)
247 {
248 	struct bcmgpio_softc * const sc = device_private(self);
249 	struct fdt_attach_args * const faa = aux;
250 	struct gpiobus_attach_args gba;
251 	bus_addr_t addr;
252 	bus_size_t size;
253 	u_int func;
254 	int error;
255 	int pin;
256 	int bank;
257 
258 	const int phandle = faa->faa_phandle;
259 	if (fdtbus_get_reg(phandle, 0, &addr, &size) != 0) {
260 		aprint_error(": couldn't get registers\n");
261 		return;
262 	}
263 
264 	sc->sc_dev = self;
265 
266 	aprint_naive("\n");
267 	aprint_normal(": GPIO controller\n");
268 
269 	sc->sc_iot = faa->faa_bst;
270 	error = bus_space_map(sc->sc_iot, addr, size, 0, &sc->sc_ioh);
271 	if (error) {
272 		aprint_error_dev(self, "couldn't map registers\n");
273 		return;
274 	}
275 
276 	mutex_init(&sc->sc_lock, MUTEX_DEFAULT, IPL_VM);
277 
278 	for (pin = 0; pin < BCMGPIO_MAXPINS; pin++) {
279 		sc->sc_gpio_pins[pin].pin_num = pin;
280 		/*
281 		 * find out pins still available for GPIO
282 		 */
283 		func = bcm283x_pin_getfunc(sc, pin);
284 
285 		if (func == BCM2835_GPIO_IN ||
286 		    func == BCM2835_GPIO_OUT) {
287 			/* XXX TRISTATE?  Really? */
288 			sc->sc_gpio_pins[pin].pin_caps = GPIO_PIN_INPUT |
289 				GPIO_PIN_OUTPUT |
290 				GPIO_PIN_PUSHPULL | GPIO_PIN_TRISTATE |
291 				GPIO_PIN_PULLUP | GPIO_PIN_PULLDOWN |
292 				GPIO_PIN_ALT0 | GPIO_PIN_ALT1 |
293 				GPIO_PIN_ALT2 | GPIO_PIN_ALT3 |
294 				GPIO_PIN_ALT4 | GPIO_PIN_ALT5;
295 			sc->sc_gpio_pins[pin].pin_intrcaps =
296 				GPIO_INTR_POS_EDGE |
297 				GPIO_INTR_NEG_EDGE |
298 				GPIO_INTR_DOUBLE_EDGE |
299 				GPIO_INTR_HIGH_LEVEL |
300 				GPIO_INTR_LOW_LEVEL |
301 				GPIO_INTR_MPSAFE;
302 			/* read initial state */
303 			sc->sc_gpio_pins[pin].pin_state =
304 				bcm2835gpio_gpio_pin_read(sc, pin);
305 			aprint_debug_dev(sc->sc_dev, "attach pin %d\n", pin);
306 		} else {
307 			sc->sc_gpio_pins[pin].pin_caps = 0;
308 			sc->sc_gpio_pins[pin].pin_state = 0;
309 			aprint_debug_dev(sc->sc_dev, "skip pin %d - func = %x\n", pin, func);
310 		}
311 	}
312 
313 	/* Initialize interrupts. */
314 	for (bank = 0; bank < BCMGPIO_NBANKS; bank++) {
315 		char intrstr[128];
316 
317 		if (!fdtbus_intr_str(phandle, bank, intrstr, sizeof(intrstr))) {
318 			aprint_error_dev(self, "failed to decode interrupt\n");
319 			continue;
320 		}
321 
322 		sc->sc_banks[bank].sc_bankno = bank;
323 		sc->sc_banks[bank].sc_bcm = sc;
324 		sc->sc_banks[bank].sc_ih =
325 		    fdtbus_intr_establish(phandle, bank, IPL_VM,
326 		    			  FDT_INTR_MPSAFE,
327 					  bcmgpio_intr, &sc->sc_banks[bank]);
328 		if (sc->sc_banks[bank].sc_ih) {
329 			aprint_normal_dev(self,
330 			    "pins %d..%d interrupting on %s\n",
331 			    bank * 32,
332 			    MIN((bank * 32) + 31, BCMGPIO_MAXPINS),
333 			    intrstr);
334 		} else {
335 			aprint_error_dev(self,
336 			    "failed to establish interrupt for pins %d..%d\n",
337 			    bank * 32,
338 			    MIN((bank * 32) + 31, BCMGPIO_MAXPINS));
339 		}
340 	}
341 
342 	fdtbus_register_gpio_controller(self, faa->faa_phandle, &bcmgpio_funcs);
343 
344 	for (int child = OF_child(phandle); child; child = OF_peer(child)) {
345 		if (!of_hasprop(child, "brcm,pins"))
346 			continue;
347 		fdtbus_register_pinctrl_config(self, child,
348 		    &bcm283x_pinctrl_funcs);
349 	}
350 
351 	fdtbus_pinctrl_configure();
352 
353 	fdtbus_register_interrupt_controller(self, phandle,
354 	    &bcmgpio_fdt_intrfuncs);
355 
356 	/* create controller tag */
357 	sc->sc_gpio_gc.gp_cookie = sc;
358 	sc->sc_gpio_gc.gp_pin_read = bcm2835gpio_gpio_pin_read;
359 	sc->sc_gpio_gc.gp_pin_write = bcm2835gpio_gpio_pin_write;
360 	sc->sc_gpio_gc.gp_pin_ctl = bcm2835gpio_gpio_pin_ctl;
361 	sc->sc_gpio_gc.gp_intr_establish = bcmgpio_gpio_intr_establish;
362 	sc->sc_gpio_gc.gp_intr_disestablish = bcmgpio_gpio_intr_disestablish;
363 	sc->sc_gpio_gc.gp_intr_str = bcmgpio_gpio_intrstr;
364 
365 	gba.gba_gc = &sc->sc_gpio_gc;
366 	gba.gba_pins = &sc->sc_gpio_pins[0];
367 	gba.gba_npins = BCMGPIO_MAXPINS;
368 	(void) config_found_ia(self, "gpiobus", &gba, gpiobus_print);
369 }
370 
371 /* GPIO interrupt support functions */
372 
373 static int
374 bcmgpio_intr(void *arg)
375 {
376 	struct bcmgpio_bank * const b = arg;
377 	struct bcmgpio_softc * const sc = b->sc_bcm;
378 	struct bcmgpio_eint *eint;
379 	uint32_t status, pending, bit;
380 	uint32_t clear_level;
381 	int (*func)(void *);
382 	int rv = 0;
383 
384 	for (;;) {
385 		status = pending = bus_space_read_4(sc->sc_iot, sc->sc_ioh,
386 		    BCM2835_GPIO_GPEDS(b->sc_bankno));
387 		if (status == 0)
388 			break;
389 
390 		/*
391 		 * This will clear the indicator for any pending
392 		 * edge-triggered pins, but level-triggered pins
393 		 * will still be indicated until the pin is
394 		 * de-asserted.  We'll have to clear level-triggered
395 		 * indicators below.
396 		 */
397 		bus_space_write_4(sc->sc_iot, sc->sc_ioh,
398 		    BCM2835_GPIO_GPEDS(b->sc_bankno), status);
399 		clear_level = 0;
400 
401 		while ((bit = ffs32(pending)) != 0) {
402 			pending &= ~__BIT(bit - 1);
403 			eint = &b->sc_eint[bit - 1];
404 			if ((func = eint->eint_func) == NULL)
405 				continue;
406 			if (eint->eint_flags & (BCMGPIO_INTR_HIGH_LEVEL |
407 						BCMGPIO_INTR_LOW_LEVEL))
408 				clear_level |= __BIT(bit - 1);
409 			const bool mpsafe =
410 			    (eint->eint_flags & BCMGPIO_INTR_MPSAFE) != 0;
411 			if (!mpsafe)
412 				KERNEL_LOCK(1, curlwp);
413 			rv |= (*func)(eint->eint_arg);
414 			if (!mpsafe)
415 				KERNEL_UNLOCK_ONE(curlwp);
416 		}
417 
418 		/*
419 		 * Now that all of the handlers have been called,
420 		 * we can clear the indicators for any level-triggered
421 		 * pins.
422 		 */
423 		if (clear_level)
424 			bus_space_write_4(sc->sc_iot, sc->sc_ioh,
425 			    BCM2835_GPIO_GPEDS(b->sc_bankno), clear_level);
426 	}
427 
428 	return (rv);
429 }
430 
431 static void *
432 bmcgpio_intr_enable(struct bcmgpio_softc *sc, int (*func)(void *), void *arg,
433 		    int bank, int pin, int flags)
434 {
435 	struct bcmgpio_eint *eint;
436 	uint32_t mask, enabled_ren, enabled_fen, enabled_hen, enabled_len;
437 	int has_edge = flags & (BCMGPIO_INTR_POS_EDGE|BCMGPIO_INTR_NEG_EDGE);
438 	int has_level = flags &
439 	    (BCMGPIO_INTR_HIGH_LEVEL|BCMGPIO_INTR_LOW_LEVEL);
440 
441 	if (bank < 0 || bank >= BCMGPIO_NBANKS)
442 		return NULL;
443 	if (pin < 0 || pin >= 32)
444 		return (NULL);
445 
446 	/* Must specify a mode. */
447 	if (!has_edge && !has_level)
448 		return (NULL);
449 
450 	/* Can't have HIGH and LOW together. */
451 	if (has_level == (BCMGPIO_INTR_HIGH_LEVEL|BCMGPIO_INTR_LOW_LEVEL))
452 		return (NULL);
453 
454 	/* Can't have EDGE and LEVEL together. */
455 	if (has_edge && has_level)
456 		return (NULL);
457 
458 	eint = &sc->sc_banks[bank].sc_eint[pin];
459 
460 	mask = __BIT(pin);
461 
462 	mutex_enter(&sc->sc_lock);
463 
464 	if (eint->eint_func != NULL) {
465 		mutex_exit(&sc->sc_lock);
466 		return (NULL);	/* in use */
467 	}
468 
469 	eint->eint_func = func;
470 	eint->eint_arg = arg;
471 	eint->eint_flags = flags;
472 	eint->eint_bank = bank;
473 	eint->eint_num = pin;
474 
475 	enabled_ren = bus_space_read_4(sc->sc_iot, sc->sc_ioh,
476 				       BCM2835_GPIO_GPREN(bank));
477 	enabled_fen = bus_space_read_4(sc->sc_iot, sc->sc_ioh,
478 				       BCM2835_GPIO_GPFEN(bank));
479 	enabled_hen = bus_space_read_4(sc->sc_iot, sc->sc_ioh,
480 				       BCM2835_GPIO_GPHEN(bank));
481 	enabled_len = bus_space_read_4(sc->sc_iot, sc->sc_ioh,
482 				       BCM2835_GPIO_GPLEN(bank));
483 
484 	enabled_ren &= ~mask;
485 	enabled_fen &= ~mask;
486 	enabled_hen &= ~mask;
487 	enabled_len &= ~mask;
488 
489 	if (flags & BCMGPIO_INTR_POS_EDGE)
490 		enabled_ren |= mask;
491 	if (flags & BCMGPIO_INTR_NEG_EDGE)
492 		enabled_fen |= mask;
493 	if (flags & BCMGPIO_INTR_HIGH_LEVEL)
494 		enabled_hen |= mask;
495 	if (flags & BCMGPIO_INTR_LOW_LEVEL)
496 		enabled_len |= mask;
497 
498 	bus_space_write_4(sc->sc_iot, sc->sc_ioh,
499 			  BCM2835_GPIO_GPREN(bank), enabled_ren);
500 	bus_space_write_4(sc->sc_iot, sc->sc_ioh,
501 			  BCM2835_GPIO_GPFEN(bank), enabled_fen);
502 	bus_space_write_4(sc->sc_iot, sc->sc_ioh,
503 			  BCM2835_GPIO_GPHEN(bank), enabled_hen);
504 	bus_space_write_4(sc->sc_iot, sc->sc_ioh,
505 			  BCM2835_GPIO_GPLEN(bank), enabled_len);
506 
507 	mutex_exit(&sc->sc_lock);
508 	return (eint);
509 }
510 
511 static void
512 bcmgpio_intr_disable(struct bcmgpio_softc *sc, struct bcmgpio_eint *eint)
513 {
514 	uint32_t mask, enabled_ren, enabled_fen, enabled_hen, enabled_len;
515 	int bank = eint->eint_bank;
516 
517 	mask = __BIT(eint->eint_num);
518 
519 	KASSERT(eint->eint_func != NULL);
520 
521 	mutex_enter(&sc->sc_lock);
522 
523 	enabled_ren = bus_space_read_4(sc->sc_iot, sc->sc_ioh,
524 				       BCM2835_GPIO_GPREN(bank));
525 	enabled_fen = bus_space_read_4(sc->sc_iot, sc->sc_ioh,
526 				       BCM2835_GPIO_GPFEN(bank));
527 	enabled_hen = bus_space_read_4(sc->sc_iot, sc->sc_ioh,
528 				       BCM2835_GPIO_GPHEN(bank));
529 	enabled_len = bus_space_read_4(sc->sc_iot, sc->sc_ioh,
530 				       BCM2835_GPIO_GPLEN(bank));
531 
532 	enabled_ren &= ~mask;
533 	enabled_fen &= ~mask;
534 	enabled_hen &= ~mask;
535 	enabled_len &= ~mask;
536 
537 	bus_space_write_4(sc->sc_iot, sc->sc_ioh,
538 			  BCM2835_GPIO_GPREN(bank), enabled_ren);
539 	bus_space_write_4(sc->sc_iot, sc->sc_ioh,
540 			  BCM2835_GPIO_GPFEN(bank), enabled_fen);
541 	bus_space_write_4(sc->sc_iot, sc->sc_ioh,
542 			  BCM2835_GPIO_GPHEN(bank), enabled_hen);
543 	bus_space_write_4(sc->sc_iot, sc->sc_ioh,
544 			  BCM2835_GPIO_GPLEN(bank), enabled_len);
545 
546 	eint->eint_func = NULL;
547 	eint->eint_arg = NULL;
548 	eint->eint_flags = 0;
549 
550 	mutex_exit(&sc->sc_lock);
551 }
552 
553 static void *
554 bcmgpio_fdt_intr_establish(device_t dev, u_int *specifier, int ipl, int flags,
555     int (*func)(void *), void *arg)
556 {
557 	struct bcmgpio_softc * const sc = device_private(dev);
558 	int eint_flags = (flags & FDT_INTR_MPSAFE) ? BCMGPIO_INTR_MPSAFE : 0;
559 
560 	if (ipl != IPL_VM) {
561 		aprint_error_dev(dev, "%s: wrong IPL %d (expected %d)\n",
562 		    __func__, ipl, IPL_VM);
563 		return (NULL);
564 	}
565 
566 	/* 1st cell is the GPIO number */
567 	/* 2nd cell is flags */
568 	const u_int bank = be32toh(specifier[0]) / 32;
569 	const u_int pin = be32toh(specifier[0]) % 32;
570 	const u_int type = be32toh(specifier[1]) & 0xf;
571 
572 	switch (type) {
573 	case FDT_INTR_TYPE_POS_EDGE:
574 		eint_flags |= BCMGPIO_INTR_POS_EDGE;
575 		break;
576 	case FDT_INTR_TYPE_NEG_EDGE:
577 		eint_flags |= BCMGPIO_INTR_NEG_EDGE;
578 		break;
579 	case FDT_INTR_TYPE_DOUBLE_EDGE:
580 		eint_flags |= BCMGPIO_INTR_POS_EDGE | BCMGPIO_INTR_NEG_EDGE;
581 		break;
582 	case FDT_INTR_TYPE_HIGH_LEVEL:
583 		eint_flags |= BCMGPIO_INTR_HIGH_LEVEL;
584 		break;
585 	case FDT_INTR_TYPE_LOW_LEVEL:
586 		eint_flags |= BCMGPIO_INTR_LOW_LEVEL;
587 		break;
588 	default:
589 		aprint_error_dev(dev, "%s: unsupported irq type 0x%x\n",
590 		    __func__, type);
591 		return (NULL);
592 	}
593 
594 	return (bmcgpio_intr_enable(sc, func, arg, bank, pin, eint_flags));
595 }
596 
597 static void
598 bcmgpio_fdt_intr_disestablish(device_t dev, void *ih)
599 {
600 	struct bcmgpio_softc * const sc = device_private(dev);
601 	struct bcmgpio_eint * const eint = ih;
602 
603 	bcmgpio_intr_disable(sc, eint);
604 }
605 
606 static void *
607 bcmgpio_gpio_intr_establish(void *vsc, int pin, int ipl, int irqmode,
608 			    int (*func)(void *), void *arg)
609 {
610 	struct bcmgpio_softc * const sc = vsc;
611 	int eint_flags = (irqmode & GPIO_INTR_MPSAFE) ? BCMGPIO_INTR_MPSAFE : 0;
612 	int bank = pin / 32;
613 	int type = irqmode & GPIO_INTR_MODE_MASK;
614 
615 	pin %= 32;
616 
617 	if (ipl != IPL_VM) {
618 		aprint_error_dev(sc->sc_dev, "%s: wrong IPL %d (expected %d)\n",
619 		    __func__, ipl, IPL_VM);
620 		return (NULL);
621 	}
622 
623 	switch (type) {
624 	case GPIO_INTR_POS_EDGE:
625 		eint_flags |= BCMGPIO_INTR_POS_EDGE;
626 		break;
627 	case GPIO_INTR_NEG_EDGE:
628 		eint_flags |= BCMGPIO_INTR_NEG_EDGE;
629 		break;
630 	case GPIO_INTR_DOUBLE_EDGE:
631 		eint_flags |= BCMGPIO_INTR_POS_EDGE | BCMGPIO_INTR_NEG_EDGE;
632 		break;
633 	case GPIO_INTR_HIGH_LEVEL:
634 		eint_flags |= BCMGPIO_INTR_HIGH_LEVEL;
635 		break;
636 	case GPIO_INTR_LOW_LEVEL:
637 		eint_flags |= BCMGPIO_INTR_LOW_LEVEL;
638 		break;
639 	default:
640 		aprint_error_dev(sc->sc_dev, "%s: unsupported irq type 0x%x\n",
641 		    __func__, type);
642 		return (NULL);
643 	}
644 
645 	return (bmcgpio_intr_enable(sc, func, arg, bank, pin, eint_flags));
646 }
647 
648 static void
649 bcmgpio_gpio_intr_disestablish(void *vsc, void *ih)
650 {
651 	struct bcmgpio_softc * const sc = vsc;
652 	struct bcmgpio_eint * const eint = ih;
653 
654 	bcmgpio_intr_disable(sc, eint);
655 }
656 
657 static bool
658 bcmgpio_gpio_intrstr(void *vsc, int pin, int irqmode, char *buf, size_t buflen)
659 {
660 
661 	if (pin < 0 || pin >= BCMGPIO_MAXPINS)
662 		return (false);
663 
664 	snprintf(buf, buflen, "GPIO %d", pin);
665 
666 	return (true);
667 }
668 
669 static bool
670 bcmgpio_fdt_intrstr(device_t dev, u_int *specifier, char *buf, size_t buflen)
671 {
672 
673 	/* 1st cell is the GPIO number */
674 	/* 2nd cell is flags */
675 	if (!specifier)
676 		return (false);
677 	const u_int bank = be32toh(specifier[0]) / 32;
678 	const u_int pin = be32toh(specifier[0]) % 32;
679 	const u_int type = be32toh(specifier[1]) & 0xf;
680 	char const* typestr;
681 
682 	if (bank >= BCMGPIO_NBANKS)
683 		return (false);
684 	switch (type) {
685 	case FDT_INTR_TYPE_DOUBLE_EDGE:
686 		typestr = "double edge";
687 		break;
688 	case FDT_INTR_TYPE_POS_EDGE:
689 		typestr = "positive edge";
690 		break;
691 	case FDT_INTR_TYPE_NEG_EDGE:
692 		typestr = "negative edge";
693 		break;
694 	case FDT_INTR_TYPE_HIGH_LEVEL:
695 		typestr = "high level";
696 		break;
697 	case FDT_INTR_TYPE_LOW_LEVEL:
698 		typestr = "low level";
699 		break;
700 	default:
701 		aprint_error_dev(dev, "%s: unsupported irq type 0x%x\n",
702 		    __func__, type);
703 
704 		return (false);
705 	}
706 
707 	snprintf(buf, buflen, "GPIO %u (%s)", (bank * 32) + pin, typestr);
708 
709 	return (true);
710 }
711 
712 /* GPIO support functions */
713 static int
714 bcm2835gpio_gpio_pin_read(void *arg, int pin)
715 {
716 	struct bcmgpio_softc *sc = arg;
717 	uint32_t val;
718 	int res;
719 
720 	val = bus_space_read_4(sc->sc_iot, sc->sc_ioh,
721 		BCM2835_GPIO_GPLEV(pin / BCM2835_GPIO_GPLEV_PINS_PER_REGISTER));
722 
723 	res = val & (1 << (pin % BCM2835_GPIO_GPLEV_PINS_PER_REGISTER)) ?
724 		GPIO_PIN_HIGH : GPIO_PIN_LOW;
725 
726 	DPRINTF(2, ("%s: gpio_read pin %d->%d\n", device_xname(sc->sc_dev),
727 	    pin, (res == GPIO_PIN_HIGH)));
728 
729 	return res;
730 }
731 
732 static void
733 bcm2835gpio_gpio_pin_write(void *arg, int pin, int value)
734 {
735 	struct bcmgpio_softc *sc = arg;
736 	bus_size_t reg;
737 
738 	if (value == GPIO_PIN_HIGH) {
739 		reg = BCM2835_GPIO_GPSET(pin / BCM2835_GPIO_GPSET_PINS_PER_REGISTER);
740 	} else {
741 		reg = BCM2835_GPIO_GPCLR(pin / BCM2835_GPIO_GPCLR_PINS_PER_REGISTER);
742 	}
743 
744 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, reg,
745 	    1 << (pin % BCM2835_GPIO_GPSET_PINS_PER_REGISTER));
746 
747 	DPRINTF(2, ("%s: gpio_write pin %d<-%d\n", device_xname(sc->sc_dev),
748 	    pin, (value == GPIO_PIN_HIGH)));
749 }
750 
751 
752 void
753 bcm283x_pin_setfunc(const struct bcmgpio_softc * const sc, u_int pin,
754     u_int func)
755 {
756 	const u_int mask = (1 << BCM2835_GPIO_GPFSEL_BITS_PER_PIN) - 1;
757 	const u_int regid = (pin / BCM2835_GPIO_GPFSEL_PINS_PER_REGISTER);
758 	const u_int shift = (pin % BCM2835_GPIO_GPFSEL_PINS_PER_REGISTER) *
759 	    BCM2835_GPIO_GPFSEL_BITS_PER_PIN;
760 	uint32_t v;
761 
762 	KASSERT(mutex_owned(&sc->sc_lock));
763 	KASSERT(func <= mask);
764 
765 	v = bus_space_read_4(sc->sc_iot, sc->sc_ioh, BCM2835_GPIO_GPFSEL(regid));
766 
767 	if (((v >> shift) & mask) == func) {
768 		return;
769 	}
770 
771 	DPRINTF(2, ("%s: gpio_write pin %d<-%d\n", device_xname(sc->sc_dev),
772 	    pin, func));
773 
774 	v &= ~(mask << shift);
775 	v |=  (func << shift);
776 
777 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, BCM2835_GPIO_GPFSEL(regid), v);
778 }
779 
780 u_int
781 bcm283x_pin_getfunc(const struct bcmgpio_softc * const sc, u_int pin)
782 {
783 	const u_int mask = (1 << BCM2835_GPIO_GPFSEL_BITS_PER_PIN) - 1;
784 	const u_int regid = (pin / BCM2835_GPIO_GPFSEL_PINS_PER_REGISTER);
785 	const u_int shift = (pin % BCM2835_GPIO_GPFSEL_PINS_PER_REGISTER) *
786 	    BCM2835_GPIO_GPFSEL_BITS_PER_PIN;
787 	uint32_t v;
788 
789 	v = bus_space_read_4(sc->sc_iot, sc->sc_ioh, BCM2835_GPIO_GPFSEL(regid));
790 
791 	return ((v >> shift) & mask);
792 }
793 
794 void
795 bcm283x_pin_setpull(const struct bcmgpio_softc * const sc, u_int pin, u_int pud)
796 {
797 
798 	KASSERT(mutex_owned(&sc->sc_lock));
799 
800 	const u_int mask = 1 << (pin % BCM2835_GPIO_GPPUD_PINS_PER_REGISTER);
801 	const u_int regid = (pin / BCM2835_GPIO_GPPUD_PINS_PER_REGISTER);
802 
803 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, BCM2835_GPIO_GPPUD, pud);
804 	delay(1);
805 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, BCM2835_GPIO_GPPUDCLK(regid), mask);
806 	delay(1);
807 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, BCM2835_GPIO_GPPUD, 0);
808 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, BCM2835_GPIO_GPPUDCLK(regid), 0);
809 }
810 
811 
812 static void
813 bcm2835gpio_gpio_pin_ctl(void *arg, int pin, int flags)
814 {
815 	struct bcmgpio_softc *sc = arg;
816 	uint32_t cmd;
817 	uint32_t altmask = GPIO_PIN_ALT0 | GPIO_PIN_ALT1 |
818 	                   GPIO_PIN_ALT2 | GPIO_PIN_ALT3 |
819 	                   GPIO_PIN_ALT4 | GPIO_PIN_ALT5;
820 
821 	DPRINTF(2, ("%s: gpio_ctl pin %d flags 0x%x\n", device_xname(sc->sc_dev), pin, flags));
822 
823 	mutex_enter(&sc->sc_lock);
824 	if (flags & (GPIO_PIN_OUTPUT|GPIO_PIN_INPUT)) {
825 		if ((flags & GPIO_PIN_INPUT) != 0) {
826 			/* for safety INPUT will overide output */
827 			bcm283x_pin_setfunc(sc, pin, BCM2835_GPIO_IN);
828 		} else {
829 			bcm283x_pin_setfunc(sc, pin, BCM2835_GPIO_OUT);
830 		}
831 	} else if ((flags & altmask) != 0) {
832 		u_int func;
833 
834 		switch (flags & altmask) {
835 		case GPIO_PIN_ALT0:
836 			func = BCM2835_GPIO_ALT0;
837 			break;
838 		case GPIO_PIN_ALT1:
839 			func = BCM2835_GPIO_ALT1;
840 			break;
841 		case GPIO_PIN_ALT2:
842 			func = BCM2835_GPIO_ALT2;
843 			break;
844 		case GPIO_PIN_ALT3:
845 			func = BCM2835_GPIO_ALT3;
846 			break;
847 		case GPIO_PIN_ALT4:
848 			func = BCM2835_GPIO_ALT4;
849 			break;
850 		case GPIO_PIN_ALT5:
851 			func = BCM2835_GPIO_ALT5;
852 			break;
853 		default:
854 			/* ignored below */
855 			func = BCM2835_GPIO_IN;
856 			break;
857 		}
858 		if (func != BCM2835_GPIO_IN)
859 			bcm283x_pin_setfunc(sc, pin, func);
860 	}
861 
862 	if (flags & (GPIO_PIN_PULLUP|GPIO_PIN_PULLDOWN)) {
863 		cmd = (flags & GPIO_PIN_PULLUP) ?
864 			BCM2835_GPIO_GPPUD_PULLUP : BCM2835_GPIO_GPPUD_PULLDOWN;
865 	} else {
866 		cmd = BCM2835_GPIO_GPPUD_PULLOFF;
867 	}
868 
869 	/* set up control signal */
870 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, BCM2835_GPIO_GPPUD, cmd);
871 	delay(1); /* wait 150 cycles */
872 	/* set clock signal */
873 	bus_space_write_4(sc->sc_iot, sc->sc_ioh,
874 	    BCM2835_GPIO_GPPUDCLK(pin / BCM2835_GPIO_GPLEV_PINS_PER_REGISTER),
875 	    1 << (pin % BCM2835_GPIO_GPPUD_PINS_PER_REGISTER));
876 	delay(1); /* wait 150 cycles */
877 	/* reset control signal and clock */
878 	bus_space_write_4(sc->sc_iot, sc->sc_ioh,
879 	    BCM2835_GPIO_GPPUD, BCM2835_GPIO_GPPUD_PULLOFF);
880 	bus_space_write_4(sc->sc_iot, sc->sc_ioh,
881 	    BCM2835_GPIO_GPPUDCLK(pin / BCM2835_GPIO_GPLEV_PINS_PER_REGISTER),
882 	    0);
883 	mutex_exit(&sc->sc_lock);
884 }
885 
886 static void *
887 bcmgpio_fdt_acquire(device_t dev, const void *data, size_t len, int flags)
888 {
889 	struct bcmgpio_softc *sc = device_private(dev);
890 	struct bcmgpio_pin *gpin;
891 	const u_int *gpio = data;
892 
893 	if (len != 12)
894 		return NULL;
895 
896 	const u_int pin = be32toh(gpio[1]);
897 	const bool actlo = be32toh(gpio[2]) & 1;
898 
899 	if (pin >= BCMGPIO_MAXPINS)
900 		return NULL;
901 
902 	gpin = kmem_alloc(sizeof(*gpin), KM_SLEEP);
903 	gpin->pin_no = pin;
904 	gpin->pin_flags = flags;
905 	gpin->pin_actlo = actlo;
906 
907 	bcm2835gpio_gpio_pin_ctl(sc, gpin->pin_no, gpin->pin_flags);
908 
909 	return gpin;
910 }
911 
912 static void
913 bcmgpio_fdt_release(device_t dev, void *priv)
914 {
915 	struct bcmgpio_softc *sc = device_private(dev);
916 	struct bcmgpio_pin *gpin = priv;
917 
918 	bcm2835gpio_gpio_pin_ctl(sc, gpin->pin_no, GPIO_PIN_INPUT);
919 	kmem_free(gpin, sizeof(*gpin));
920 }
921 
922 static int
923 bcmgpio_fdt_read(device_t dev, void *priv, bool raw)
924 {
925 	struct bcmgpio_softc *sc = device_private(dev);
926 	struct bcmgpio_pin *gpin = priv;
927 	int val;
928 
929 	val = bcm2835gpio_gpio_pin_read(sc, gpin->pin_no);
930 
931 	if (!raw && gpin->pin_actlo)
932 		val = !val;
933 
934 	return val;
935 }
936 
937 static void
938 bcmgpio_fdt_write(device_t dev, void *priv, int val, bool raw)
939 {
940 	struct bcmgpio_softc *sc = device_private(dev);
941 	struct bcmgpio_pin *gpin = priv;
942 
943 	if (!raw && gpin->pin_actlo)
944 		val = !val;
945 
946 	bcm2835gpio_gpio_pin_write(sc, gpin->pin_no, val);
947 }
948