1 /*- 2 * Copyright (c) 1998, 2001 Nicolas Souchu 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * $FreeBSD: src/sys/dev/iicbus/iic.c,v 1.43 2009/01/26 13:53:39 raj Exp $ 27 */ 28 29 #include <sys/param.h> 30 #include <sys/buf.h> 31 #include <sys/bus.h> 32 #include <sys/conf.h> 33 #include <sys/fcntl.h> 34 #include <sys/kernel.h> 35 #include <sys/malloc.h> 36 #include <sys/module.h> 37 #include <sys/systm.h> 38 #include <sys/uio.h> 39 40 #include <bus/iicbus/iiconf.h> 41 #include <bus/iicbus/iicbus.h> 42 #include <bus/iicbus/iic.h> 43 44 #include "iicbus_if.h" 45 46 #define BUFSIZE 1024 47 48 struct iic_softc { 49 50 device_t sc_dev; 51 u_char sc_addr; /* 7 bit address on iicbus */ 52 int sc_count; /* >0 if device opened */ 53 54 char sc_buffer[BUFSIZE]; /* output buffer */ 55 char sc_inbuf[BUFSIZE]; /* input buffer */ 56 57 cdev_t sc_devnode; 58 }; 59 60 #define IIC_LOCK(sc) 61 #define IIC_UNLOCK(sc) 62 63 static int iic_probe(device_t); 64 static int iic_attach(device_t); 65 static int iic_detach(device_t); 66 static void iic_identify(driver_t *driver, device_t parent); 67 68 static devclass_t iic_devclass; 69 70 static device_method_t iic_methods[] = { 71 /* device interface */ 72 DEVMETHOD(device_identify, iic_identify), 73 DEVMETHOD(device_probe, iic_probe), 74 DEVMETHOD(device_attach, iic_attach), 75 DEVMETHOD(device_detach, iic_detach), 76 77 /* iicbus interface */ 78 DEVMETHOD(iicbus_intr, iicbus_generic_intr), 79 80 DEVMETHOD_END 81 }; 82 83 static driver_t iic_driver = { 84 "iic", 85 iic_methods, 86 sizeof(struct iic_softc), 87 }; 88 89 static d_open_t iicopen; 90 static d_close_t iicclose; 91 static d_write_t iicwrite; 92 static d_read_t iicread; 93 static d_ioctl_t iicioctl; 94 95 static struct dev_ops iic_ops = { 96 { "iic", 0, 0 }, 97 .d_open = iicopen, 98 .d_close = iicclose, 99 .d_read = iicread, 100 .d_write = iicwrite, 101 .d_ioctl = iicioctl, 102 }; 103 104 static void 105 iic_identify(driver_t *driver, device_t parent) 106 { 107 108 if (device_find_child(parent, "iic", -1) == NULL) 109 BUS_ADD_CHILD(parent, parent, 0, "iic", -1); 110 } 111 112 static int 113 iic_probe(device_t dev) 114 { 115 if (iicbus_get_addr(dev) > 0) 116 return (ENXIO); 117 118 device_set_desc(dev, "I2C generic I/O"); 119 120 return (0); 121 } 122 123 static int 124 iic_attach(device_t dev) 125 { 126 struct iic_softc *sc = (struct iic_softc *)device_get_softc(dev); 127 128 sc->sc_devnode = make_dev(&iic_ops, device_get_unit(dev), 129 UID_ROOT, GID_WHEEL, 130 0600, "iic%d", device_get_unit(dev)); 131 if (sc->sc_devnode == NULL) { 132 device_printf(dev, "failed to create character device\n"); 133 return (ENXIO); 134 } 135 sc->sc_devnode->si_drv1 = sc; 136 137 return (0); 138 } 139 140 static int 141 iic_detach(device_t dev) 142 { 143 struct iic_softc *sc = (struct iic_softc *)device_get_softc(dev); 144 145 if (sc->sc_devnode) 146 dev_ops_remove_minor(&iic_ops, device_get_unit(dev)); 147 148 return (0); 149 } 150 151 static int 152 iicopen(struct dev_open_args *ap) 153 { 154 cdev_t dev = ap->a_head.a_dev; 155 struct iic_softc *sc = dev->si_drv1; 156 157 IIC_LOCK(sc); 158 if (sc->sc_count > 0) { 159 IIC_UNLOCK(sc); 160 return (EBUSY); 161 } 162 163 sc->sc_count++; 164 IIC_UNLOCK(sc); 165 166 return (0); 167 } 168 169 static int 170 iicclose(struct dev_close_args *ap) 171 { 172 cdev_t dev = ap->a_head.a_dev; 173 struct iic_softc *sc = dev->si_drv1; 174 175 IIC_LOCK(sc); 176 if (!sc->sc_count) { 177 /* XXX: I don't think this can happen. */ 178 IIC_UNLOCK(sc); 179 return (EINVAL); 180 } 181 182 sc->sc_count--; 183 184 if (sc->sc_count < 0) 185 panic("%s: iic_count < 0!", __func__); 186 IIC_UNLOCK(sc); 187 188 return (0); 189 } 190 191 static int 192 iicwrite(struct dev_write_args *ap) 193 { 194 cdev_t dev = ap->a_head.a_dev; 195 struct uio *uio = ap->a_uio; 196 struct iic_softc *sc = dev->si_drv1; 197 device_t iicdev = sc->sc_dev; 198 int sent, error, count; 199 200 IIC_LOCK(sc); 201 if (!sc->sc_addr) { 202 IIC_UNLOCK(sc); 203 return (EINVAL); 204 } 205 206 if (sc->sc_count == 0) { 207 /* XXX: I don't think this can happen. */ 208 IIC_UNLOCK(sc); 209 return (EINVAL); 210 } 211 212 error = iicbus_request_bus(device_get_parent(iicdev), iicdev, 213 IIC_DONTWAIT); 214 if (error) { 215 IIC_UNLOCK(sc); 216 return (error); 217 } 218 219 count = (int)szmin(uio->uio_resid, BUFSIZE); 220 uiomove(sc->sc_buffer, (size_t)count, uio); 221 222 error = iicbus_block_write(device_get_parent(iicdev), sc->sc_addr, 223 sc->sc_buffer, count, &sent); 224 225 iicbus_release_bus(device_get_parent(iicdev), iicdev); 226 IIC_UNLOCK(sc); 227 228 return (error); 229 } 230 231 static int 232 iicread(struct dev_read_args *ap) 233 { 234 cdev_t dev = ap->a_head.a_dev; 235 struct uio *uio = ap->a_uio; 236 struct iic_softc *sc = dev->si_drv1; 237 device_t iicdev = sc->sc_dev; 238 int len, error = 0; 239 int bufsize; 240 241 IIC_LOCK(sc); 242 if (!sc->sc_addr) { 243 IIC_UNLOCK(sc); 244 return (EINVAL); 245 } 246 247 if (sc->sc_count == 0) { 248 /* XXX: I don't think this can happen. */ 249 IIC_UNLOCK(sc); 250 return (EINVAL); 251 } 252 253 error = iicbus_request_bus(device_get_parent(iicdev), iicdev, 254 IIC_DONTWAIT); 255 if (error) { 256 IIC_UNLOCK(sc); 257 return (error); 258 } 259 260 /* max amount of data to read */ 261 len = (int)szmin(uio->uio_resid, BUFSIZE); 262 263 error = iicbus_block_read(device_get_parent(iicdev), sc->sc_addr, 264 sc->sc_inbuf, len, &bufsize); 265 if (error) { 266 IIC_UNLOCK(sc); 267 return (error); 268 } 269 270 if (bufsize > uio->uio_resid) 271 panic("%s: too much data read!", __func__); 272 273 iicbus_release_bus(device_get_parent(iicdev), iicdev); 274 275 error = uiomove(sc->sc_inbuf, (size_t)bufsize, uio); 276 IIC_UNLOCK(sc); 277 return (error); 278 } 279 280 static int 281 iicioctl(struct dev_ioctl_args *ap) 282 { 283 cdev_t dev = ap->a_head.a_dev; 284 u_long cmd = ap->a_cmd; 285 caddr_t data = ap->a_data; 286 int flags = ap->a_fflag; 287 struct iic_softc *sc = dev->si_drv1; 288 device_t iicdev = sc->sc_dev; 289 device_t parent = device_get_parent(iicdev); 290 struct iiccmd *s = (struct iiccmd *)data; 291 struct iic_rdwr_data *d = (struct iic_rdwr_data *)data; 292 struct iic_msg *m; 293 int error, count, i; 294 char *buf = NULL; 295 void **usrbufs = NULL; 296 297 if ((error = iicbus_request_bus(device_get_parent(iicdev), iicdev, 298 (flags & O_NONBLOCK) ? IIC_DONTWAIT : 299 (IIC_WAIT | IIC_INTR)))) 300 return (error); 301 302 switch (cmd) { 303 case I2CSTART: 304 IIC_LOCK(sc); 305 error = iicbus_start(parent, s->slave, 0); 306 307 /* 308 * Implicitly set the chip addr to the slave addr passed as 309 * parameter. Consequently, start/stop shall be called before 310 * the read or the write of a block. 311 */ 312 if (!error) 313 sc->sc_addr = s->slave; 314 IIC_UNLOCK(sc); 315 316 break; 317 318 case I2CSTOP: 319 error = iicbus_stop(parent); 320 break; 321 322 case I2CRSTCARD: 323 error = iicbus_reset(parent, IIC_UNKNOWN, 0, NULL); 324 break; 325 326 case I2CWRITE: 327 if (s->count <= 0) { 328 error = EINVAL; 329 break; 330 } 331 buf = kmalloc((unsigned long)s->count, M_TEMP, M_WAITOK); 332 error = copyin(s->buf, buf, s->count); 333 if (error) 334 break; 335 error = iicbus_write(parent, buf, s->count, &count, 10); 336 break; 337 338 case I2CREAD: 339 if (s->count <= 0) { 340 error = EINVAL; 341 break; 342 } 343 buf = kmalloc((unsigned long)s->count, M_TEMP, M_WAITOK); 344 error = iicbus_read(parent, buf, s->count, &count, s->last, 10); 345 if (error) 346 break; 347 error = copyout(buf, s->buf, s->count); 348 break; 349 350 case I2CRDWR: 351 buf = kmalloc(sizeof(*d->msgs) * d->nmsgs, M_TEMP, M_WAITOK); 352 usrbufs = kmalloc(sizeof(void *) * d->nmsgs, M_TEMP, M_ZERO | M_WAITOK); 353 error = copyin(d->msgs, buf, sizeof(*d->msgs) * d->nmsgs); 354 if (error) 355 break; 356 /* Alloc kernel buffers for userland data, copyin write data */ 357 for (i = 0; i < d->nmsgs; i++) { 358 m = &((struct iic_msg *)buf)[i]; 359 usrbufs[i] = m->buf; 360 m->buf = kmalloc(m->len, M_TEMP, M_WAITOK); 361 if (!(m->flags & IIC_M_RD)) 362 copyin(usrbufs[i], m->buf, m->len); 363 } 364 error = iicbus_transfer(parent, (struct iic_msg *)buf, d->nmsgs); 365 /* Copyout all read segments, free up kernel buffers */ 366 for (i = 0; i < d->nmsgs; i++) { 367 m = &((struct iic_msg *)buf)[i]; 368 if (m->flags & IIC_M_RD) 369 copyout(m->buf, usrbufs[i], m->len); 370 kfree(m->buf, M_TEMP); 371 } 372 kfree(usrbufs, M_TEMP); 373 break; 374 375 case I2CRPTSTART: 376 error = iicbus_repeated_start(parent, s->slave, 0); 377 break; 378 379 default: 380 error = ENOTTY; 381 } 382 383 iicbus_release_bus(device_get_parent(iicdev), iicdev); 384 385 if (buf != NULL) 386 kfree(buf, M_TEMP); 387 return (error); 388 } 389 390 DRIVER_MODULE(iic, iicbus, iic_driver, iic_devclass, NULL, NULL); 391 MODULE_DEPEND(iic, iicbus, IICBUS_MINVER, IICBUS_PREFVER, IICBUS_MAXVER); 392 MODULE_VERSION(iic, 1); 393