sys/bus/iicbus/iic.c

   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);