1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2012 Oleksandr Tymoshenko <gonzo@FreeBSD.org>
5 * Copyright (c) 2012-2015 Luiz Otavio O Souza <loos@FreeBSD.org>
6 * All rights reserved.
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 #include <sys/cdefs.h>
31 #include "opt_platform.h"
32
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/bus.h>
36 #include <sys/gpio.h>
37 #include <sys/kernel.h>
38 #include <sys/lock.h>
39 #include <sys/module.h>
40 #include <sys/sx.h>
41 #include <sys/proc.h>
42
43 #include <dev/gpio/gpiobusvar.h>
44 #include <dev/ofw/ofw_bus.h>
45
46 #include <arm/broadcom/bcm2835/bcm2835_firmware.h>
47
48 #include "gpio_if.h"
49
50 #define RPI_FW_GPIO_PINS 8
51 #define RPI_FW_GPIO_BASE 128
52 #define RPI_FW_GPIO_DEFAULT_CAPS (GPIO_PIN_INPUT | GPIO_PIN_OUTPUT)
53
54 struct rpi_fw_gpio_softc {
55 device_t sc_busdev;
56 device_t sc_firmware;
57 struct sx sc_sx;
58 struct gpio_pin sc_gpio_pins[RPI_FW_GPIO_PINS];
59 uint8_t sc_gpio_state;
60 };
61
62 #define RPI_FW_GPIO_LOCK(_sc) sx_xlock(&(_sc)->sc_sx)
63 #define RPI_FW_GPIO_UNLOCK(_sc) sx_xunlock(&(_sc)->sc_sx)
64
65 static struct ofw_compat_data compat_data[] = {
66 {"raspberrypi,firmware-gpio", 1},
67 {NULL, 0}
68 };
69
70 static int
rpi_fw_gpio_pin_configure(struct rpi_fw_gpio_softc * sc,struct gpio_pin * pin,unsigned int flags)71 rpi_fw_gpio_pin_configure(struct rpi_fw_gpio_softc *sc, struct gpio_pin *pin,
72 unsigned int flags)
73 {
74 union msg_get_gpio_config old_cfg;
75 union msg_set_gpio_config new_cfg;
76 int rv;
77
78 bzero(&old_cfg, sizeof(old_cfg));
79 bzero(&new_cfg, sizeof(new_cfg));
80 old_cfg.req.gpio = RPI_FW_GPIO_BASE + pin->gp_pin;
81
82 RPI_FW_GPIO_LOCK(sc);
83 rv = bcm2835_firmware_property(sc->sc_firmware,
84 BCM2835_FIRMWARE_TAG_GET_GPIO_CONFIG, &old_cfg, sizeof(old_cfg));
85 if (rv == 0 && old_cfg.resp.gpio != 0)
86 rv = EIO;
87 if (rv != 0)
88 goto fail;
89
90 new_cfg.req.gpio = RPI_FW_GPIO_BASE + pin->gp_pin;
91 if (flags & GPIO_PIN_INPUT) {
92 new_cfg.req.dir = BCM2835_FIRMWARE_GPIO_IN;
93 new_cfg.req.state = 0;
94 pin->gp_flags = GPIO_PIN_INPUT;
95 } else if (flags & GPIO_PIN_OUTPUT) {
96 new_cfg.req.dir = BCM2835_FIRMWARE_GPIO_OUT;
97 if (flags & (GPIO_PIN_PRESET_HIGH | GPIO_PIN_PRESET_LOW)) {
98 if (flags & GPIO_PIN_PRESET_HIGH) {
99 new_cfg.req.state = 1;
100 sc->sc_gpio_state |= (1 << pin->gp_pin);
101 } else {
102 new_cfg.req.state = 0;
103 sc->sc_gpio_state &= ~(1 << pin->gp_pin);
104 }
105 } else {
106 if ((sc->sc_gpio_state & (1 << pin->gp_pin)) != 0) {
107 new_cfg.req.state = 1;
108 } else {
109 new_cfg.req.state = 0;
110 }
111 }
112 pin->gp_flags = GPIO_PIN_OUTPUT;
113 } else {
114 new_cfg.req.dir = old_cfg.resp.dir;
115 /* Use the old state to decide high/low */
116 if ((sc->sc_gpio_state & (1 << pin->gp_pin)) != 0)
117 new_cfg.req.state = 1;
118 else
119 new_cfg.req.state = 0;
120 }
121 new_cfg.req.pol = old_cfg.resp.pol;
122 new_cfg.req.term_en = 0;
123 new_cfg.req.term_pull_up = 0;
124
125 rv = bcm2835_firmware_property(sc->sc_firmware,
126 BCM2835_FIRMWARE_TAG_SET_GPIO_CONFIG, &new_cfg, sizeof(new_cfg));
127
128 fail:
129 RPI_FW_GPIO_UNLOCK(sc);
130
131 return (rv);
132 }
133
134 static device_t
rpi_fw_gpio_get_bus(device_t dev)135 rpi_fw_gpio_get_bus(device_t dev)
136 {
137 struct rpi_fw_gpio_softc *sc;
138
139 sc = device_get_softc(dev);
140
141 return (sc->sc_busdev);
142 }
143
144 static int
rpi_fw_gpio_pin_max(device_t dev,int * maxpin)145 rpi_fw_gpio_pin_max(device_t dev, int *maxpin)
146 {
147
148 *maxpin = RPI_FW_GPIO_PINS - 1;
149 return (0);
150 }
151
152 static int
rpi_fw_gpio_pin_getcaps(device_t dev,uint32_t pin,uint32_t * caps)153 rpi_fw_gpio_pin_getcaps(device_t dev, uint32_t pin, uint32_t *caps)
154 {
155 struct rpi_fw_gpio_softc *sc;
156 int i;
157
158 sc = device_get_softc(dev);
159 for (i = 0; i < RPI_FW_GPIO_PINS; i++) {
160 if (sc->sc_gpio_pins[i].gp_pin == pin)
161 break;
162 }
163
164 if (i >= RPI_FW_GPIO_PINS)
165 return (EINVAL);
166
167 *caps = RPI_FW_GPIO_DEFAULT_CAPS;
168 return (0);
169 }
170
171 static int
rpi_fw_gpio_pin_getflags(device_t dev,uint32_t pin,uint32_t * flags)172 rpi_fw_gpio_pin_getflags(device_t dev, uint32_t pin, uint32_t *flags)
173 {
174 struct rpi_fw_gpio_softc *sc = device_get_softc(dev);
175 int i;
176
177 for (i = 0; i < RPI_FW_GPIO_PINS; i++) {
178 if (sc->sc_gpio_pins[i].gp_pin == pin)
179 break;
180 }
181
182 if (i >= RPI_FW_GPIO_PINS)
183 return (EINVAL);
184
185 RPI_FW_GPIO_LOCK(sc);
186 *flags = sc->sc_gpio_pins[i].gp_flags;
187 RPI_FW_GPIO_UNLOCK(sc);
188
189 return (0);
190 }
191
192 static int
rpi_fw_gpio_pin_getname(device_t dev,uint32_t pin,char * name)193 rpi_fw_gpio_pin_getname(device_t dev, uint32_t pin, char *name)
194 {
195 struct rpi_fw_gpio_softc *sc;
196 int i;
197
198 sc = device_get_softc(dev);
199 for (i = 0; i < RPI_FW_GPIO_PINS; i++) {
200 if (sc->sc_gpio_pins[i].gp_pin == pin)
201 break;
202 }
203
204 if (i >= RPI_FW_GPIO_PINS)
205 return (EINVAL);
206
207 RPI_FW_GPIO_LOCK(sc);
208 memcpy(name, sc->sc_gpio_pins[i].gp_name, GPIOMAXNAME);
209 RPI_FW_GPIO_UNLOCK(sc);
210
211 return (0);
212 }
213
214 static int
rpi_fw_gpio_pin_setflags(device_t dev,uint32_t pin,uint32_t flags)215 rpi_fw_gpio_pin_setflags(device_t dev, uint32_t pin, uint32_t flags)
216 {
217 struct rpi_fw_gpio_softc *sc;
218 int i;
219
220 sc = device_get_softc(dev);
221 for (i = 0; i < RPI_FW_GPIO_PINS; i++) {
222 if (sc->sc_gpio_pins[i].gp_pin == pin)
223 break;
224 }
225
226 if (i >= RPI_FW_GPIO_PINS)
227 return (EINVAL);
228
229 return (rpi_fw_gpio_pin_configure(sc, &sc->sc_gpio_pins[i], flags));
230 }
231
232 static int
rpi_fw_gpio_pin_set(device_t dev,uint32_t pin,unsigned int value)233 rpi_fw_gpio_pin_set(device_t dev, uint32_t pin, unsigned int value)
234 {
235 struct rpi_fw_gpio_softc *sc;
236 union msg_set_gpio_state state;
237 int i, rv;
238
239 sc = device_get_softc(dev);
240 for (i = 0; i < RPI_FW_GPIO_PINS; i++) {
241 if (sc->sc_gpio_pins[i].gp_pin == pin)
242 break;
243 }
244 if (i >= RPI_FW_GPIO_PINS)
245 return (EINVAL);
246
247 state.req.gpio = RPI_FW_GPIO_BASE + pin;
248 state.req.state = value;
249
250 RPI_FW_GPIO_LOCK(sc);
251 rv = bcm2835_firmware_property(sc->sc_firmware,
252 BCM2835_FIRMWARE_TAG_SET_GPIO_STATE, &state, sizeof(state));
253 /* The firmware sets gpio to 0 on success */
254 if (rv == 0 && state.resp.gpio != 0)
255 rv = EINVAL;
256 if (rv == 0) {
257 sc->sc_gpio_pins[i].gp_flags &= ~(GPIO_PIN_PRESET_HIGH |
258 GPIO_PIN_PRESET_LOW);
259 if (value)
260 sc->sc_gpio_state |= (1 << i);
261 else
262 sc->sc_gpio_state &= ~(1 << i);
263 }
264 RPI_FW_GPIO_UNLOCK(sc);
265
266 return (rv);
267 }
268
269 static int
rpi_fw_gpio_pin_get(device_t dev,uint32_t pin,unsigned int * val)270 rpi_fw_gpio_pin_get(device_t dev, uint32_t pin, unsigned int *val)
271 {
272 struct rpi_fw_gpio_softc *sc;
273 union msg_get_gpio_state state;
274 int i, rv;
275
276 sc = device_get_softc(dev);
277 for (i = 0; i < RPI_FW_GPIO_PINS; i++) {
278 if (sc->sc_gpio_pins[i].gp_pin == pin)
279 break;
280 }
281 if (i >= RPI_FW_GPIO_PINS)
282 return (EINVAL);
283
284 bzero(&state, sizeof(state));
285 state.req.gpio = RPI_FW_GPIO_BASE + pin;
286
287 RPI_FW_GPIO_LOCK(sc);
288 rv = bcm2835_firmware_property(sc->sc_firmware,
289 BCM2835_FIRMWARE_TAG_GET_GPIO_STATE, &state, sizeof(state));
290 RPI_FW_GPIO_UNLOCK(sc);
291
292 /* The firmware sets gpio to 0 on success */
293 if (rv == 0 && state.resp.gpio != 0)
294 rv = EINVAL;
295 if (rv == 0)
296 *val = !state.resp.state;
297
298 return (rv);
299 }
300
301 static int
rpi_fw_gpio_pin_toggle(device_t dev,uint32_t pin)302 rpi_fw_gpio_pin_toggle(device_t dev, uint32_t pin)
303 {
304 struct rpi_fw_gpio_softc *sc;
305 union msg_get_gpio_state old_state;
306 union msg_set_gpio_state new_state;
307 int i, rv;
308
309 sc = device_get_softc(dev);
310 for (i = 0; i < RPI_FW_GPIO_PINS; i++) {
311 if (sc->sc_gpio_pins[i].gp_pin == pin)
312 break;
313 }
314 if (i >= RPI_FW_GPIO_PINS)
315 return (EINVAL);
316
317 bzero(&old_state, sizeof(old_state));
318 bzero(&new_state, sizeof(new_state));
319
320 old_state.req.gpio = RPI_FW_GPIO_BASE + pin;
321 new_state.req.gpio = RPI_FW_GPIO_BASE + pin;
322
323 RPI_FW_GPIO_LOCK(sc);
324 rv = bcm2835_firmware_property(sc->sc_firmware,
325 BCM2835_FIRMWARE_TAG_GET_GPIO_STATE, &old_state, sizeof(old_state));
326 /* The firmware sets gpio to 0 on success */
327 if (rv == 0 && old_state.resp.gpio == 0) {
328 /* Set the new state to invert the GPIO */
329 new_state.req.state = !old_state.resp.state;
330 rv = bcm2835_firmware_property(sc->sc_firmware,
331 BCM2835_FIRMWARE_TAG_SET_GPIO_STATE, &new_state,
332 sizeof(new_state));
333 }
334 if (rv == 0 && (old_state.resp.gpio != 0 || new_state.resp.gpio != 0))
335 rv = EINVAL;
336 RPI_FW_GPIO_UNLOCK(sc);
337
338 return (rv);
339 }
340
341 static int
rpi_fw_gpio_probe(device_t dev)342 rpi_fw_gpio_probe(device_t dev)
343 {
344
345 if (!ofw_bus_status_okay(dev))
346 return (ENXIO);
347
348 if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0)
349 return (ENXIO);
350
351 device_set_desc(dev, "Raspberry Pi Firmware GPIO controller");
352 return (BUS_PROBE_DEFAULT);
353 }
354
355 static int
rpi_fw_gpio_attach(device_t dev)356 rpi_fw_gpio_attach(device_t dev)
357 {
358 union msg_get_gpio_config cfg;
359 struct rpi_fw_gpio_softc *sc;
360 char *names;
361 phandle_t gpio;
362 int i, nelems, elm_pos, rv;
363
364 sc = device_get_softc(dev);
365 sc->sc_firmware = device_get_parent(dev);
366 sx_init(&sc->sc_sx, "Raspberry Pi firmware gpio");
367 /* Find our node. */
368 gpio = ofw_bus_get_node(dev);
369 if (!OF_hasprop(gpio, "gpio-controller"))
370 /* This is not a GPIO controller. */
371 goto fail;
372
373 nelems = OF_getprop_alloc(gpio, "gpio-line-names", (void **)&names);
374 if (nelems <= 0)
375 names = NULL;
376 elm_pos = 0;
377 for (i = 0; i < RPI_FW_GPIO_PINS; i++) {
378 /* Set the current pin name */
379 if (names != NULL && elm_pos < nelems &&
380 names[elm_pos] != '\0') {
381 snprintf(sc->sc_gpio_pins[i].gp_name, GPIOMAXNAME,
382 "%s", names + elm_pos);
383 /* Find the next pin name */
384 elm_pos += strlen(names + elm_pos) + 1;
385 } else {
386 snprintf(sc->sc_gpio_pins[i].gp_name, GPIOMAXNAME,
387 "pin %d", i);
388 }
389
390 sc->sc_gpio_pins[i].gp_pin = i;
391 sc->sc_gpio_pins[i].gp_caps = RPI_FW_GPIO_DEFAULT_CAPS;
392
393 bzero(&cfg, sizeof(cfg));
394 cfg.req.gpio = RPI_FW_GPIO_BASE + i;
395 rv = bcm2835_firmware_property(sc->sc_firmware,
396 BCM2835_FIRMWARE_TAG_GET_GPIO_CONFIG, &cfg, sizeof(cfg));
397 if (rv == 0 && cfg.resp.gpio == 0) {
398 if (cfg.resp.dir == BCM2835_FIRMWARE_GPIO_IN)
399 sc->sc_gpio_pins[i].gp_flags = GPIO_PIN_INPUT;
400 else
401 sc->sc_gpio_pins[i].gp_flags = GPIO_PIN_OUTPUT;
402 } else {
403 sc->sc_gpio_pins[i].gp_flags = GPIO_PIN_INPUT;
404 }
405 }
406 free(names, M_OFWPROP);
407 sc->sc_busdev = gpiobus_attach_bus(dev);
408 if (sc->sc_busdev == NULL)
409 goto fail;
410
411 return (0);
412
413 fail:
414 sx_destroy(&sc->sc_sx);
415
416 return (ENXIO);
417 }
418
419 static int
rpi_fw_gpio_detach(device_t dev)420 rpi_fw_gpio_detach(device_t dev)
421 {
422
423 return (EBUSY);
424 }
425
426 static device_method_t rpi_fw_gpio_methods[] = {
427 /* Device interface */
428 DEVMETHOD(device_probe, rpi_fw_gpio_probe),
429 DEVMETHOD(device_attach, rpi_fw_gpio_attach),
430 DEVMETHOD(device_detach, rpi_fw_gpio_detach),
431
432 /* GPIO protocol */
433 DEVMETHOD(gpio_get_bus, rpi_fw_gpio_get_bus),
434 DEVMETHOD(gpio_pin_max, rpi_fw_gpio_pin_max),
435 DEVMETHOD(gpio_pin_getname, rpi_fw_gpio_pin_getname),
436 DEVMETHOD(gpio_pin_getflags, rpi_fw_gpio_pin_getflags),
437 DEVMETHOD(gpio_pin_getcaps, rpi_fw_gpio_pin_getcaps),
438 DEVMETHOD(gpio_pin_setflags, rpi_fw_gpio_pin_setflags),
439 DEVMETHOD(gpio_pin_get, rpi_fw_gpio_pin_get),
440 DEVMETHOD(gpio_pin_set, rpi_fw_gpio_pin_set),
441 DEVMETHOD(gpio_pin_toggle, rpi_fw_gpio_pin_toggle),
442
443 DEVMETHOD_END
444 };
445
446 static driver_t rpi_fw_gpio_driver = {
447 "gpio",
448 rpi_fw_gpio_methods,
449 sizeof(struct rpi_fw_gpio_softc),
450 };
451
452 EARLY_DRIVER_MODULE(rpi_fw_gpio, bcm2835_firmware, rpi_fw_gpio_driver, 0, 0,
453 BUS_PASS_INTERRUPT + BUS_PASS_ORDER_LATE);
454