1 /* $NetBSD: gpio.c,v 1.13 2007/12/14 01:49:23 dyoung Exp $ */ 2 /* $OpenBSD: gpio.c,v 1.6 2006/01/14 12:33:49 grange Exp $ */ 3 4 /* 5 * Copyright (c) 2004, 2006 Alexander Yurchenko <grange@openbsd.org> 6 * 7 * Permission to use, copy, modify, and distribute this software for any 8 * purpose with or without fee is hereby granted, provided that the above 9 * copyright notice and this permission notice appear in all copies. 10 * 11 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 13 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 15 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 16 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 17 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 18 */ 19 20 #include <sys/cdefs.h> 21 __KERNEL_RCSID(0, "$NetBSD: gpio.c,v 1.13 2007/12/14 01:49:23 dyoung Exp $"); 22 23 /* 24 * General Purpose Input/Output framework. 25 */ 26 27 #include <sys/param.h> 28 #include <sys/systm.h> 29 #include <sys/conf.h> 30 #include <sys/device.h> 31 #include <sys/ioctl.h> 32 #include <sys/gpio.h> 33 #include <sys/vnode.h> 34 35 #include <dev/gpio/gpiovar.h> 36 37 #include "locators.h" 38 39 struct gpio_softc { 40 struct device sc_dev; 41 42 gpio_chipset_tag_t sc_gc; /* our GPIO controller */ 43 gpio_pin_t *sc_pins; /* pins array */ 44 int sc_npins; /* total number of pins */ 45 46 int sc_opened; 47 int sc_dying; 48 }; 49 50 int gpio_match(struct device *, struct cfdata *, void *); 51 void gpio_attach(struct device *, struct device *, void *); 52 bool gpio_resume(device_t); 53 int gpio_detach(struct device *, int); 54 int gpio_activate(struct device *, enum devact); 55 int gpio_search(struct device *, struct cfdata *, const int *, void *); 56 int gpio_print(void *, const char *); 57 58 CFATTACH_DECL(gpio, sizeof(struct gpio_softc), 59 gpio_match, gpio_attach, gpio_detach, gpio_activate); 60 61 dev_type_open(gpioopen); 62 dev_type_close(gpioclose); 63 dev_type_ioctl(gpioioctl); 64 65 const struct cdevsw gpio_cdevsw = { 66 gpioopen, gpioclose, noread, nowrite, gpioioctl, 67 nostop, notty, nopoll, nommap, nokqfilter, D_OTHER, 68 }; 69 70 extern struct cfdriver gpio_cd; 71 72 int 73 gpio_match(struct device *parent, struct cfdata *cf, 74 void *aux) 75 { 76 77 return (1); 78 } 79 80 bool 81 gpio_resume(device_t self) 82 { 83 struct gpio_softc *sc = device_private(self); 84 int pin; 85 86 for (pin = 0; pin < sc->sc_npins; pin++) { 87 gpiobus_pin_ctl(sc->sc_gc, pin, sc->sc_pins[pin].pin_flags); 88 gpiobus_pin_write(sc->sc_gc, pin, sc->sc_pins[pin].pin_state); 89 } 90 return true; 91 } 92 93 void 94 gpio_attach(struct device *parent, struct device *self, void *aux) 95 { 96 struct gpio_softc *sc = device_private(self); 97 struct gpiobus_attach_args *gba = aux; 98 99 sc->sc_gc = gba->gba_gc; 100 sc->sc_pins = gba->gba_pins; 101 sc->sc_npins = gba->gba_npins; 102 103 printf(": %d pins\n", sc->sc_npins); 104 105 if (!pmf_device_register(self, NULL, gpio_resume)) 106 aprint_error_dev(self, "couldn't establish power handler\n"); 107 108 /* 109 * Attach all devices that can be connected to the GPIO pins 110 * described in the kernel configuration file. 111 */ 112 config_search_ia(gpio_search, self, "gpio", sc); 113 } 114 115 int 116 gpio_detach(struct device *self, int flags) 117 { 118 #if 0 119 int maj, mn; 120 121 /* Locate the major number */ 122 for (maj = 0; maj < nchrdev; maj++) 123 if (cdevsw[maj].d_open == gpioopen) 124 break; 125 126 /* Nuke the vnodes for any open instances (calls close) */ 127 mn = device_unit(self); 128 vdevgone(maj, mn, mn, VCHR); 129 #endif 130 131 return (0); 132 } 133 134 int 135 gpio_activate(struct device *self, enum devact act) 136 { 137 struct gpio_softc *sc = device_private(self); 138 139 switch (act) { 140 case DVACT_ACTIVATE: 141 return (EOPNOTSUPP); 142 case DVACT_DEACTIVATE: 143 sc->sc_dying = 1; 144 break; 145 } 146 147 return (0); 148 } 149 150 int 151 gpio_search(struct device *parent, struct cfdata *cf, 152 const int *ldesc, void *aux) 153 { 154 struct gpio_attach_args ga; 155 156 ga.ga_gpio = aux; 157 ga.ga_offset = cf->cf_loc[GPIOCF_OFFSET]; 158 ga.ga_mask = cf->cf_loc[GPIOCF_MASK]; 159 160 if (config_match(parent, cf, &ga) > 0) 161 config_attach(parent, cf, &ga, gpio_print); 162 163 return (0); 164 } 165 166 int 167 gpio_print(void *aux, const char *pnp) 168 { 169 struct gpio_attach_args *ga = aux; 170 int i; 171 172 printf(" pins"); 173 for (i = 0; i < 32; i++) 174 if (ga->ga_mask & (1 << i)) 175 printf(" %d", ga->ga_offset + i); 176 177 return (UNCONF); 178 } 179 180 int 181 gpiobus_print(void *aux, const char *pnp) 182 { 183 #if 0 184 struct gpiobus_attach_args *gba = aux; 185 #endif 186 if (pnp != NULL) 187 printf("%s at %s", "gpiobus", pnp); 188 189 return (UNCONF); 190 } 191 192 int 193 gpio_pin_map(void *gpio, int offset, u_int32_t mask, struct gpio_pinmap *map) 194 { 195 struct gpio_softc *sc = gpio; 196 int npins, pin, i; 197 198 npins = gpio_npins(mask); 199 if (npins > sc->sc_npins) 200 return (1); 201 202 for (npins = 0, i = 0; i < 32; i++) 203 if (mask & (1 << i)) { 204 pin = offset + i; 205 if (pin < 0 || pin >= sc->sc_npins) 206 return (1); 207 if (sc->sc_pins[pin].pin_mapped) 208 return (1); 209 sc->sc_pins[pin].pin_mapped = 1; 210 map->pm_map[npins++] = pin; 211 } 212 map->pm_size = npins; 213 214 return (0); 215 } 216 217 void 218 gpio_pin_unmap(void *gpio, struct gpio_pinmap *map) 219 { 220 struct gpio_softc *sc = gpio; 221 int pin, i; 222 223 for (i = 0; i < map->pm_size; i++) { 224 pin = map->pm_map[i]; 225 sc->sc_pins[pin].pin_mapped = 0; 226 } 227 } 228 229 int 230 gpio_pin_read(void *gpio, struct gpio_pinmap *map, int pin) 231 { 232 struct gpio_softc *sc = gpio; 233 234 return (gpiobus_pin_read(sc->sc_gc, map->pm_map[pin])); 235 } 236 237 void 238 gpio_pin_write(void *gpio, struct gpio_pinmap *map, int pin, int value) 239 { 240 struct gpio_softc *sc = gpio; 241 242 gpiobus_pin_write(sc->sc_gc, map->pm_map[pin], value); 243 sc->sc_pins[map->pm_map[pin]].pin_state = value; 244 } 245 246 void 247 gpio_pin_ctl(void *gpio, struct gpio_pinmap *map, int pin, int flags) 248 { 249 struct gpio_softc *sc = gpio; 250 251 return (gpiobus_pin_ctl(sc->sc_gc, map->pm_map[pin], flags)); 252 } 253 254 int 255 gpio_pin_caps(void *gpio, struct gpio_pinmap *map, int pin) 256 { 257 struct gpio_softc *sc = gpio; 258 259 return (sc->sc_pins[map->pm_map[pin]].pin_caps); 260 } 261 262 int 263 gpio_npins(u_int32_t mask) 264 { 265 int npins, i; 266 267 for (npins = 0, i = 0; i < 32; i++) 268 if (mask & (1 << i)) 269 npins++; 270 271 return (npins); 272 } 273 274 int 275 gpioopen(dev_t dev, int flag, int mode, 276 struct lwp *l) 277 { 278 struct gpio_softc *sc; 279 280 sc = (struct gpio_softc *)device_lookup(&gpio_cd, minor(dev)); 281 if (sc == NULL) 282 return (ENXIO); 283 284 if (sc->sc_opened) 285 return (EBUSY); 286 sc->sc_opened = 1; 287 288 return (0); 289 } 290 291 int 292 gpioclose(dev_t dev, int flag, int mode, 293 struct lwp *l) 294 { 295 struct gpio_softc *sc; 296 297 sc = (struct gpio_softc *)device_lookup(&gpio_cd, minor(dev)); 298 sc->sc_opened = 0; 299 300 return (0); 301 } 302 303 int 304 gpioioctl(dev_t dev, u_long cmd, void *data, int flag, 305 struct lwp *l) 306 { 307 struct gpio_softc *sc; 308 gpio_chipset_tag_t gc; 309 struct gpio_info *info; 310 struct gpio_pin_op *op; 311 struct gpio_pin_ctl *ctl; 312 int pin, value, flags; 313 314 sc = (struct gpio_softc *)device_lookup(&gpio_cd, minor(dev)); 315 gc = sc->sc_gc; 316 317 if (cmd != GPIOINFO && !device_is_active(&sc->sc_dev)) 318 return EBUSY; 319 320 switch (cmd) { 321 case GPIOINFO: 322 info = (struct gpio_info *)data; 323 324 info->gpio_npins = sc->sc_npins; 325 break; 326 case GPIOPINREAD: 327 op = (struct gpio_pin_op *)data; 328 329 pin = op->gp_pin; 330 if (pin < 0 || pin >= sc->sc_npins) 331 return (EINVAL); 332 333 /* return read value */ 334 op->gp_value = gpiobus_pin_read(gc, pin); 335 break; 336 case GPIOPINWRITE: 337 op = (struct gpio_pin_op *)data; 338 339 pin = op->gp_pin; 340 if (pin < 0 || pin >= sc->sc_npins) 341 return (EINVAL); 342 if (sc->sc_pins[pin].pin_mapped) 343 return (EBUSY); 344 345 value = op->gp_value; 346 if (value != GPIO_PIN_LOW && value != GPIO_PIN_HIGH) 347 return (EINVAL); 348 349 gpiobus_pin_write(gc, pin, value); 350 /* return old value */ 351 op->gp_value = sc->sc_pins[pin].pin_state; 352 /* update current value */ 353 sc->sc_pins[pin].pin_state = value; 354 break; 355 case GPIOPINTOGGLE: 356 op = (struct gpio_pin_op *)data; 357 358 pin = op->gp_pin; 359 if (pin < 0 || pin >= sc->sc_npins) 360 return (EINVAL); 361 if (sc->sc_pins[pin].pin_mapped) 362 return (EBUSY); 363 364 value = (sc->sc_pins[pin].pin_state == GPIO_PIN_LOW ? 365 GPIO_PIN_HIGH : GPIO_PIN_LOW); 366 gpiobus_pin_write(gc, pin, value); 367 /* return old value */ 368 op->gp_value = sc->sc_pins[pin].pin_state; 369 /* update current value */ 370 sc->sc_pins[pin].pin_state = value; 371 break; 372 case GPIOPINCTL: 373 ctl = (struct gpio_pin_ctl *)data; 374 375 pin = ctl->gp_pin; 376 if (pin < 0 || pin >= sc->sc_npins) 377 return (EINVAL); 378 if (sc->sc_pins[pin].pin_mapped) 379 return (EBUSY); 380 381 flags = ctl->gp_flags; 382 /* check that the controller supports all requested flags */ 383 if ((flags & sc->sc_pins[pin].pin_caps) != flags) 384 return (ENODEV); 385 386 ctl->gp_caps = sc->sc_pins[pin].pin_caps; 387 /* return old value */ 388 ctl->gp_flags = sc->sc_pins[pin].pin_flags; 389 if (flags > 0) { 390 gpiobus_pin_ctl(gc, pin, flags); 391 /* update current value */ 392 sc->sc_pins[pin].pin_flags = flags; 393 } 394 break; 395 default: 396 return (ENOTTY); 397 } 398 399 return (0); 400 } 401