drivers/media/IR/lirc_dev.c

   1 /*
   2  * LIRC base driver
   3  *
   4  * by Artur Lipowski <alipowski@interia.pl>
   5  *
   6  *  This program is free software; you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation; either version 2 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  This program is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with this program; if not, write to the Free Software
  18  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  *
  20  */
  21
  22 #include <linux/module.h>
  23 #include <linux/kernel.h>
  24 #include <linux/sched.h>
  25 #include <linux/errno.h>
  26 #include <linux/ioctl.h>
  27 #include <linux/fs.h>
  28 #include <linux/poll.h>
  29 #include <linux/completion.h>
  30 #include <linux/errno.h>
  31 #include <linux/mutex.h>
  32 #include <linux/wait.h>
  33 #include <linux/unistd.h>
  34 #include <linux/kthread.h>
  35 #include <linux/bitops.h>
  36 #include <linux/device.h>
  37 #include <linux/cdev.h>
  38
  39 #include <media/lirc.h>
  40 #include <media/lirc_dev.h>
  41
  42 static int debug;
  43
  44 #define IRCTL_DEV_NAME  "BaseRemoteCtl"
  45 #define NOPLUG          -1
  46 #define LOGHEAD         "lirc_dev (%s[%d]): "
  47
  48 static dev_t lirc_base_dev;
  49
  50 struct irctl {
  51         struct lirc_driver d;
  52         int attached;
  53         int open;
  54
  55         struct mutex irctl_lock;
  56         struct lirc_buffer *buf;
  57         unsigned int chunk_size;
  58
  59         struct task_struct *task;
  60         long jiffies_to_wait;
  61
  62         struct cdev cdev;
  63 };
  64
  65 static DEFINE_MUTEX(lirc_dev_lock);
  66
  67 static struct irctl *irctls[MAX_IRCTL_DEVICES];
  68
  69 /* Only used for sysfs but defined to void otherwise */
  70 static struct class *lirc_class;
  71
  72 /*  helper function
  73  *  initializes the irctl structure
  74  */
  75 static void init_irctl(struct irctl *ir)
  76 {
  77         dev_dbg(ir->d.dev, LOGHEAD "initializing irctl\n",
  78                 ir->d.name, ir->d.minor);
  79         mutex_init(&ir->irctl_lock);
  80         ir->d.minor = NOPLUG;
  81 }
  82
  83 static void cleanup(struct irctl *ir)
  84 {
  85         dev_dbg(ir->d.dev, LOGHEAD "cleaning up\n", ir->d.name, ir->d.minor);
  86
  87         device_destroy(lirc_class, MKDEV(MAJOR(lirc_base_dev), ir->d.minor));
  88
  89         if (ir->buf != ir->d.rbuf) {
  90                 lirc_buffer_free(ir->buf);
  91                 kfree(ir->buf);
  92         }
  93         ir->buf = NULL;
  94 }
  95
  96 /*  helper function
  97  *  reads key codes from driver and puts them into buffer
  98  *  returns 0 on success
  99  */
 100 static int add_to_buf(struct irctl *ir)
 101 {
 102         if (ir->d.add_to_buf) {
 103                 int res = -ENODATA;
 104                 int got_data = 0;
 105
 106                 /*
 107                  * service the device as long as it is returning
 108                  * data and we have space
 109                  */
 110 get_data:
 111                 res = ir->d.add_to_buf(ir->d.data, ir->buf);
 112                 if (res == 0) {
 113                         got_data++;
 114                         goto get_data;
 115                 }
 116
 117                 if (res == -ENODEV)
 118                         kthread_stop(ir->task);
 119
 120                 return got_data ? 0 : res;
 121         }
 122
 123         return 0;
 124 }
 125
 126 /* main function of the polling thread
 127  */
 128 static int lirc_thread(void *irctl)
 129 {
 130         struct irctl *ir = irctl;
 131
 132         dev_dbg(ir->d.dev, LOGHEAD "poll thread started\n",
 133                 ir->d.name, ir->d.minor);
 134
 135         do {
 136                 if (ir->open) {
 137                         if (ir->jiffies_to_wait) {
 138                                 set_current_state(TASK_INTERRUPTIBLE);
 139                                 schedule_timeout(ir->jiffies_to_wait);
 140                         }
 141                         if (kthread_should_stop())
 142                                 break;
 143                         if (!add_to_buf(ir))
 144                                 wake_up_interruptible(&ir->buf->wait_poll);
 145                 } else {
 146                         set_current_state(TASK_INTERRUPTIBLE);
 147                         schedule();
 148                 }
 149         } while (!kthread_should_stop());
 150
 151         dev_dbg(ir->d.dev, LOGHEAD "poll thread ended\n",
 152                 ir->d.name, ir->d.minor);
 153
 154         return 0;
 155 }
 156
 157
 158 static struct file_operations fops = {
 159         .owner          = THIS_MODULE,
 160         .read           = lirc_dev_fop_read,
 161         .write          = lirc_dev_fop_write,
 162         .poll           = lirc_dev_fop_poll,
 163         .unlocked_ioctl = lirc_dev_fop_ioctl,
 164         .open           = lirc_dev_fop_open,
 165         .release        = lirc_dev_fop_close,
 166 };
 167
 168 static int lirc_cdev_add(struct irctl *ir)
 169 {
 170         int retval;
 171         struct lirc_driver *d = &ir->d;
 172
 173         if (d->fops) {
 174                 cdev_init(&ir->cdev, d->fops);
 175                 ir->cdev.owner = d->owner;
 176         } else {
 177                 cdev_init(&ir->cdev, &fops);
 178                 ir->cdev.owner = THIS_MODULE;
 179         }
 180         kobject_set_name(&ir->cdev.kobj, "lirc%d", d->minor);
 181
 182         retval = cdev_add(&ir->cdev, MKDEV(MAJOR(lirc_base_dev), d->minor), 1);
 183         if (retval)
 184                 kobject_put(&ir->cdev.kobj);
 185
 186         return retval;
 187 }
 188
 189 int lirc_register_driver(struct lirc_driver *d)
 190 {
 191         struct irctl *ir;
 192         int minor;
 193         int bytes_in_key;
 194         unsigned int chunk_size;
 195         unsigned int buffer_size;
 196         int err;
 197
 198         if (!d) {
 199                 printk(KERN_ERR "lirc_dev: lirc_register_driver: "
 200                        "driver pointer must be not NULL!\n");
 201                 err = -EBADRQC;
 202                 goto out;
 203         }
 204
 205         if (MAX_IRCTL_DEVICES <= d->minor) {
 206                 dev_err(d->dev, "lirc_dev: lirc_register_driver: "
 207                         "\"minor\" must be between 0 and %d (%d)!\n",
 208                         MAX_IRCTL_DEVICES-1, d->minor);
 209                 err = -EBADRQC;
 210                 goto out;
 211         }
 212
 213         if (1 > d->code_length || (BUFLEN * 8) < d->code_length) {
 214                 dev_err(d->dev, "lirc_dev: lirc_register_driver: "
 215                         "code length in bits for minor (%d) "
 216                         "must be less than %d!\n",
 217                         d->minor, BUFLEN * 8);
 218                 err = -EBADRQC;
 219                 goto out;
 220         }
 221
 222         dev_dbg(d->dev, "lirc_dev: lirc_register_driver: sample_rate: %d\n",
 223                 d->sample_rate);
 224         if (d->sample_rate) {
 225                 if (2 > d->sample_rate || HZ < d->sample_rate) {
 226                         dev_err(d->dev, "lirc_dev: lirc_register_driver: "
 227                                 "sample_rate must be between 2 and %d!\n", HZ);
 228                         err = -EBADRQC;
 229                         goto out;
 230                 }
 231                 if (!d->add_to_buf) {
 232                         dev_err(d->dev, "lirc_dev: lirc_register_driver: "
 233                                 "add_to_buf cannot be NULL when "
 234                                 "sample_rate is set\n");
 235                         err = -EBADRQC;
 236                         goto out;
 237                 }
 238         } else if (!(d->fops && d->fops->read) && !d->rbuf) {
 239                 dev_err(d->dev, "lirc_dev: lirc_register_driver: "
 240                         "fops->read and rbuf cannot all be NULL!\n");
 241                 err = -EBADRQC;
 242                 goto out;
 243         } else if (!d->rbuf) {
 244                 if (!(d->fops && d->fops->read && d->fops->poll &&
 245                       d->fops->unlocked_ioctl)) {
 246                         dev_err(d->dev, "lirc_dev: lirc_register_driver: "
 247                                 "neither read, poll nor unlocked_ioctl can be NULL!\n");
 248                         err = -EBADRQC;
 249                         goto out;
 250                 }
 251         }
 252
 253         mutex_lock(&lirc_dev_lock);
 254
 255         minor = d->minor;
 256
 257         if (minor < 0) {
 258                 /* find first free slot for driver */
 259                 for (minor = 0; minor < MAX_IRCTL_DEVICES; minor++)
 260                         if (!irctls[minor])
 261                                 break;
 262                 if (MAX_IRCTL_DEVICES == minor) {
 263                         dev_err(d->dev, "lirc_dev: lirc_register_driver: "
 264                                 "no free slots for drivers!\n");
 265                         err = -ENOMEM;
 266                         goto out_lock;
 267                 }
 268         } else if (irctls[minor]) {
 269                 dev_err(d->dev, "lirc_dev: lirc_register_driver: "
 270                         "minor (%d) just registered!\n", minor);
 271                 err = -EBUSY;
 272                 goto out_lock;
 273         }
 274
 275         ir = kzalloc(sizeof(struct irctl), GFP_KERNEL);
 276         if (!ir) {
 277                 err = -ENOMEM;
 278                 goto out_lock;
 279         }
 280         init_irctl(ir);
 281         irctls[minor] = ir;
 282         d->minor = minor;
 283
 284         if (d->sample_rate) {
 285                 ir->jiffies_to_wait = HZ / d->sample_rate;
 286         } else {
 287                 /* it means - wait for external event in task queue */
 288                 ir->jiffies_to_wait = 0;
 289         }
 290
 291         /* some safety check 8-) */
 292         d->name[sizeof(d->name)-1] = '\0';
 293
 294         bytes_in_key = BITS_TO_LONGS(d->code_length) +
 295                         (d->code_length % 8 ? 1 : 0);
 296         buffer_size = d->buffer_size ? d->buffer_size : BUFLEN / bytes_in_key;
 297         chunk_size  = d->chunk_size  ? d->chunk_size  : bytes_in_key;
 298
 299         if (d->rbuf) {
 300                 ir->buf = d->rbuf;
 301         } else {
 302                 ir->buf = kmalloc(sizeof(struct lirc_buffer), GFP_KERNEL);
 303                 if (!ir->buf) {
 304                         err = -ENOMEM;
 305                         goto out_lock;
 306                 }
 307                 err = lirc_buffer_init(ir->buf, chunk_size, buffer_size);
 308                 if (err) {
 309                         kfree(ir->buf);
 310                         goto out_lock;
 311                 }
 312         }
 313         ir->chunk_size = ir->buf->chunk_size;
 314
 315         if (d->features == 0)
 316                 d->features = LIRC_CAN_REC_LIRCCODE;
 317
 318         ir->d = *d;
 319         ir->d.minor = minor;
 320
 321         device_create(lirc_class, ir->d.dev,
 322                       MKDEV(MAJOR(lirc_base_dev), ir->d.minor), NULL,
 323                       "lirc%u", ir->d.minor);
 324
 325         if (d->sample_rate) {
 326                 /* try to fire up polling thread */
 327                 ir->task = kthread_run(lirc_thread, (void *)ir, "lirc_dev");
 328                 if (IS_ERR(ir->task)) {
 329                         dev_err(d->dev, "lirc_dev: lirc_register_driver: "
 330                                 "cannot run poll thread for minor = %d\n",
 331                                 d->minor);
 332                         err = -ECHILD;
 333                         goto out_sysfs;
 334                 }
 335         }
 336
 337         err = lirc_cdev_add(ir);
 338         if (err)
 339                 goto out_sysfs;
 340
 341         ir->attached = 1;
 342         mutex_unlock(&lirc_dev_lock);
 343
 344         dev_info(ir->d.dev, "lirc_dev: driver %s registered at minor = %d\n",
 345                  ir->d.name, ir->d.minor);
 346         return minor;
 347
 348 out_sysfs:
 349         device_destroy(lirc_class, MKDEV(MAJOR(lirc_base_dev), ir->d.minor));
 350 out_lock:
 351         mutex_unlock(&lirc_dev_lock);
 352 out:
 353         return err;
 354 }
 355 EXPORT_SYMBOL(lirc_register_driver);
 356
 357 int lirc_unregister_driver(int minor)
 358 {
 359         struct irctl *ir;
 360
 361         if (minor < 0 || minor >= MAX_IRCTL_DEVICES) {
 362                 printk(KERN_ERR "lirc_dev: lirc_unregister_driver: "
 363                        "\"minor (%d)\" must be between 0 and %d!\n",
 364                        minor, MAX_IRCTL_DEVICES-1);
 365                 return -EBADRQC;
 366         }
 367
 368         ir = irctls[minor];
 369
 370         mutex_lock(&lirc_dev_lock);
 371
 372         if (ir->d.minor != minor) {
 373                 printk(KERN_ERR "lirc_dev: lirc_unregister_driver: "
 374                        "minor (%d) device not registered!", minor);
 375                 mutex_unlock(&lirc_dev_lock);
 376                 return -ENOENT;
 377         }
 378
 379         /* end up polling thread */
 380         if (ir->task)
 381                 kthread_stop(ir->task);
 382
 383         dev_dbg(ir->d.dev, "lirc_dev: driver %s unregistered from minor = %d\n",
 384                 ir->d.name, ir->d.minor);
 385
 386         ir->attached = 0;
 387         if (ir->open) {
 388                 dev_dbg(ir->d.dev, LOGHEAD "releasing opened driver\n",
 389                         ir->d.name, ir->d.minor);
 390                 wake_up_interruptible(&ir->buf->wait_poll);
 391                 mutex_lock(&ir->irctl_lock);
 392                 ir->d.set_use_dec(ir->d.data);
 393                 module_put(ir->d.owner);
 394                 mutex_unlock(&ir->irctl_lock);
 395                 cdev_del(&ir->cdev);
 396         } else {
 397                 cleanup(ir);
 398                 cdev_del(&ir->cdev);
 399                 kfree(ir);
 400                 irctls[minor] = NULL;
 401         }
 402
 403         mutex_unlock(&lirc_dev_lock);
 404
 405         return 0;
 406 }
 407 EXPORT_SYMBOL(lirc_unregister_driver);
 408
 409 int lirc_dev_fop_open(struct inode *inode, struct file *file)
 410 {
 411         struct irctl *ir;
 412         int retval = 0;
 413
 414         if (iminor(inode) >= MAX_IRCTL_DEVICES) {
 415                 printk(KERN_WARNING "lirc_dev [%d]: open result = -ENODEV\n",
 416                        iminor(inode));
 417                 return -ENODEV;
 418         }
 419
 420         if (mutex_lock_interruptible(&lirc_dev_lock))
 421                 return -ERESTARTSYS;
 422
 423         ir = irctls[iminor(inode)];
 424         if (!ir) {
 425                 retval = -ENODEV;
 426                 goto error;
 427         }
 428         file->private_data = ir;
 429
 430         dev_dbg(ir->d.dev, LOGHEAD "open called\n", ir->d.name, ir->d.minor);
 431
 432         if (ir->d.minor == NOPLUG) {
 433                 retval = -ENODEV;
 434                 goto error;
 435         }
 436
 437         if (ir->open) {
 438                 retval = -EBUSY;
 439                 goto error;
 440         }
 441
 442         if (try_module_get(ir->d.owner)) {
 443                 ++ir->open;
 444                 retval = ir->d.set_use_inc(ir->d.data);
 445
 446                 if (retval) {
 447                         module_put(ir->d.owner);
 448                         --ir->open;
 449                 } else {
 450                         lirc_buffer_clear(ir->buf);
 451                 }
 452                 if (ir->task)
 453                         wake_up_process(ir->task);
 454         }
 455
 456 error:
 457         if (ir)
 458                 dev_dbg(ir->d.dev, LOGHEAD "open result = %d\n",
 459                         ir->d.name, ir->d.minor, retval);
 460
 461         mutex_unlock(&lirc_dev_lock);
 462
 463         return retval;
 464 }
 465 EXPORT_SYMBOL(lirc_dev_fop_open);
 466
 467 int lirc_dev_fop_close(struct inode *inode, struct file *file)
 468 {
 469         struct irctl *ir = irctls[iminor(inode)];
 470
 471         dev_dbg(ir->d.dev, LOGHEAD "close called\n", ir->d.name, ir->d.minor);
 472
 473         WARN_ON(mutex_lock_killable(&lirc_dev_lock));
 474
 475         --ir->open;
 476         if (ir->attached) {
 477                 ir->d.set_use_dec(ir->d.data);
 478                 module_put(ir->d.owner);
 479         } else {
 480                 cleanup(ir);
 481                 irctls[ir->d.minor] = NULL;
 482                 kfree(ir);
 483         }
 484
 485         mutex_unlock(&lirc_dev_lock);
 486
 487         return 0;
 488 }
 489 EXPORT_SYMBOL(lirc_dev_fop_close);
 490
 491 unsigned int lirc_dev_fop_poll(struct file *file, poll_table *wait)
 492 {
 493         struct irctl *ir = irctls[iminor(file->f_dentry->d_inode)];
 494         unsigned int ret;
 495
 496         dev_dbg(ir->d.dev, LOGHEAD "poll called\n", ir->d.name, ir->d.minor);
 497
 498         if (!ir->attached) {
 499                 mutex_unlock(&ir->irctl_lock);
 500                 return POLLERR;
 501         }
 502
 503         poll_wait(file, &ir->buf->wait_poll, wait);
 504
 505         if (ir->buf)
 506                 if (lirc_buffer_empty(ir->buf))
 507                         ret = 0;
 508                 else
 509                         ret = POLLIN | POLLRDNORM;
 510         else
 511                 ret = POLLERR;
 512
 513         dev_dbg(ir->d.dev, LOGHEAD "poll result = %d\n",
 514                 ir->d.name, ir->d.minor, ret);
 515
 516         return ret;
 517 }
 518 EXPORT_SYMBOL(lirc_dev_fop_poll);
 519
 520 long lirc_dev_fop_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 521 {
 522         unsigned long mode;
 523         int result = 0;
 524         struct irctl *ir = file->private_data;
 525
 526         dev_dbg(ir->d.dev, LOGHEAD "ioctl called (0x%x)\n",
 527                 ir->d.name, ir->d.minor, cmd);
 528
 529         if (ir->d.minor == NOPLUG || !ir->attached) {
 530                 dev_dbg(ir->d.dev, LOGHEAD "ioctl result = -ENODEV\n",
 531                         ir->d.name, ir->d.minor);
 532                 return -ENODEV;
 533         }
 534
 535         mutex_lock(&ir->irctl_lock);
 536
 537         switch (cmd) {
 538         case LIRC_GET_FEATURES:
 539                 result = put_user(ir->d.features, (unsigned long *)arg);
 540                 break;
 541         case LIRC_GET_REC_MODE:
 542                 if (!(ir->d.features & LIRC_CAN_REC_MASK)) {
 543                         result = -ENOSYS;
 544                         break;
 545                 }
 546
 547                 result = put_user(LIRC_REC2MODE
 548                                   (ir->d.features & LIRC_CAN_REC_MASK),
 549                                   (unsigned long *)arg);
 550                 break;
 551         case LIRC_SET_REC_MODE:
 552                 if (!(ir->d.features & LIRC_CAN_REC_MASK)) {
 553                         result = -ENOSYS;
 554                         break;
 555                 }
 556
 557                 result = get_user(mode, (unsigned long *)arg);
 558                 if (!result && !(LIRC_MODE2REC(mode) & ir->d.features))
 559                         result = -EINVAL;
 560                 /*
 561                  * FIXME: We should actually set the mode somehow but
 562                  * for now, lirc_serial doesn't support mode changing either
 563                  */
 564                 break;
 565         case LIRC_GET_LENGTH:
 566                 result = put_user(ir->d.code_length, (unsigned long *)arg);
 567                 break;
 568         case LIRC_GET_MIN_TIMEOUT:
 569                 if (!(ir->d.features & LIRC_CAN_SET_REC_TIMEOUT) ||
 570                     ir->d.min_timeout == 0) {
 571                         result = -ENOSYS;
 572                         break;
 573                 }
 574
 575                 result = put_user(ir->d.min_timeout, (unsigned long *)arg);
 576                 break;
 577         case LIRC_GET_MAX_TIMEOUT:
 578                 if (!(ir->d.features & LIRC_CAN_SET_REC_TIMEOUT) ||
 579                     ir->d.max_timeout == 0) {
 580                         result = -ENOSYS;
 581                         break;
 582                 }
 583
 584                 result = put_user(ir->d.max_timeout, (unsigned long *)arg);
 585                 break;
 586         default:
 587                 result = -EINVAL;
 588         }
 589
 590         dev_dbg(ir->d.dev, LOGHEAD "ioctl result = %d\n",
 591                 ir->d.name, ir->d.minor, result);
 592
 593         mutex_unlock(&ir->irctl_lock);
 594
 595         return result;
 596 }
 597 EXPORT_SYMBOL(lirc_dev_fop_ioctl);
 598
 599 ssize_t lirc_dev_fop_read(struct file *file,
 600                           char *buffer,
 601                           size_t length,
 602                           loff_t *ppos)
 603 {
 604         struct irctl *ir = irctls[iminor(file->f_dentry->d_inode)];
 605         unsigned char buf[ir->chunk_size];
 606         int ret = 0, written = 0;
 607         DECLARE_WAITQUEUE(wait, current);
 608
 609         dev_dbg(ir->d.dev, LOGHEAD "read called\n", ir->d.name, ir->d.minor);
 610
 611         if (mutex_lock_interruptible(&ir->irctl_lock))
 612                 return -ERESTARTSYS;
 613         if (!ir->attached) {
 614                 mutex_unlock(&ir->irctl_lock);
 615                 return -ENODEV;
 616         }
 617
 618         if (length % ir->chunk_size) {
 619                 dev_dbg(ir->d.dev, LOGHEAD "read result = -EINVAL\n",
 620                         ir->d.name, ir->d.minor);
 621                 mutex_unlock(&ir->irctl_lock);
 622                 return -EINVAL;
 623         }
 624
 625         /*
 626          * we add ourselves to the task queue before buffer check
 627          * to avoid losing scan code (in case when queue is awaken somewhere
 628          * between while condition checking and scheduling)
 629          */
 630         add_wait_queue(&ir->buf->wait_poll, &wait);
 631         set_current_state(TASK_INTERRUPTIBLE);
 632
 633         /*
 634          * while we didn't provide 'length' bytes, device is opened in blocking
 635          * mode and 'copy_to_user' is happy, wait for data.
 636          */
 637         while (written < length && ret == 0) {
 638                 if (lirc_buffer_empty(ir->buf)) {
 639                         /* According to the read(2) man page, 'written' can be
 640                          * returned as less than 'length', instead of blocking
 641                          * again, returning -EWOULDBLOCK, or returning
 642                          * -ERESTARTSYS */
 643                         if (written)
 644                                 break;
 645                         if (file->f_flags & O_NONBLOCK) {
 646                                 ret = -EWOULDBLOCK;
 647                                 break;
 648                         }
 649                         if (signal_pending(current)) {
 650                                 ret = -ERESTARTSYS;
 651                                 break;
 652                         }
 653
 654                         mutex_unlock(&ir->irctl_lock);
 655                         schedule();
 656                         set_current_state(TASK_INTERRUPTIBLE);
 657
 658                         if (mutex_lock_interruptible(&ir->irctl_lock)) {
 659                                 ret = -ERESTARTSYS;
 660                                 remove_wait_queue(&ir->buf->wait_poll, &wait);
 661                                 set_current_state(TASK_RUNNING);
 662                                 goto out_unlocked;
 663                         }
 664
 665                         if (!ir->attached) {
 666                                 ret = -ENODEV;
 667                                 break;
 668                         }
 669                 } else {
 670                         lirc_buffer_read(ir->buf, buf);
 671                         ret = copy_to_user((void *)buffer+written, buf,
 672                                            ir->buf->chunk_size);
 673                         written += ir->buf->chunk_size;
 674                 }
 675         }
 676
 677         remove_wait_queue(&ir->buf->wait_poll, &wait);
 678         set_current_state(TASK_RUNNING);
 679         mutex_unlock(&ir->irctl_lock);
 680
 681 out_unlocked:
 682         dev_dbg(ir->d.dev, LOGHEAD "read result = %s (%d)\n",
 683                 ir->d.name, ir->d.minor, ret ? "-EFAULT" : "OK", ret);
 684
 685         return ret ? ret : written;
 686 }
 687 EXPORT_SYMBOL(lirc_dev_fop_read);
 688
 689 void *lirc_get_pdata(struct file *file)
 690 {
 691         void *data = NULL;
 692
 693         if (file && file->f_dentry && file->f_dentry->d_inode &&
 694             file->f_dentry->d_inode->i_rdev) {
 695                 struct irctl *ir;
 696                 ir = irctls[iminor(file->f_dentry->d_inode)];
 697                 data = ir->d.data;
 698         }
 699
 700         return data;
 701 }
 702 EXPORT_SYMBOL(lirc_get_pdata);
 703
 704
 705 ssize_t lirc_dev_fop_write(struct file *file, const char *buffer,
 706                            size_t length, loff_t *ppos)
 707 {
 708         struct irctl *ir = irctls[iminor(file->f_dentry->d_inode)];
 709
 710         dev_dbg(ir->d.dev, LOGHEAD "write called\n", ir->d.name, ir->d.minor);
 711
 712         if (!ir->attached)
 713                 return -ENODEV;
 714
 715         return -EINVAL;
 716 }
 717 EXPORT_SYMBOL(lirc_dev_fop_write);
 718
 719
 720 static int __init lirc_dev_init(void)
 721 {
 722         int retval;
 723
 724         lirc_class = class_create(THIS_MODULE, "lirc");
 725         if (IS_ERR(lirc_class)) {
 726                 retval = PTR_ERR(lirc_class);
 727                 printk(KERN_ERR "lirc_dev: class_create failed\n");
 728                 goto error;
 729         }
 730
 731         retval = alloc_chrdev_region(&lirc_base_dev, 0, MAX_IRCTL_DEVICES,
 732                                      IRCTL_DEV_NAME);
 733         if (retval) {
 734                 class_destroy(lirc_class);
 735                 printk(KERN_ERR "lirc_dev: alloc_chrdev_region failed\n");
 736                 goto error;
 737         }
 738
 739
 740         printk(KERN_INFO "lirc_dev: IR Remote Control driver registered, "
 741                "major %d \n", MAJOR(lirc_base_dev));
 742
 743 error:
 744         return retval;
 745 }
 746
 747
 748
 749 static void __exit lirc_dev_exit(void)
 750 {
 751         class_destroy(lirc_class);
 752         unregister_chrdev_region(lirc_base_dev, MAX_IRCTL_DEVICES);
 753         printk(KERN_INFO "lirc_dev: module unloaded\n");
 754 }
 755
 756 module_init(lirc_dev_init);
 757 module_exit(lirc_dev_exit);
 758
 759 MODULE_DESCRIPTION("LIRC base driver module");
 760 MODULE_AUTHOR("Artur Lipowski");
 761 MODULE_LICENSE("GPL");
 762
 763 module_param(debug, bool, S_IRUGO | S_IWUSR);
 764 MODULE_PARM_DESC(debug, "Enable debugging messages");