release/src-rt-6.x.4708/linux/linux-2.6.36/drivers/net/irda/sir_dev.c

   1 /*********************************************************************
   2  *
   3  *      sir_dev.c:      irda sir network device
   4  *
   5  *      Copyright (c) 2002 Martin Diehl
   6  *
   7  *      This program is free software; you can redistribute it and/or
   8  *      modify it under the terms of the GNU General Public License as
   9  *      published by the Free Software Foundation; either version 2 of
  10  *      the License, or (at your option) any later version.
  11  *
  12  ********************************************************************/
  13
  14 #include <linux/module.h>
  15 #include <linux/kernel.h>
  16 #include <linux/slab.h>
  17 #include <linux/init.h>
  18 #include <linux/delay.h>
  19
  20 #include <net/irda/irda.h>
  21 #include <net/irda/wrapper.h>
  22 #include <net/irda/irda_device.h>
  23
  24 #include "sir-dev.h"
  25
  26
  27 static struct workqueue_struct *irda_sir_wq;
  28
  29 /* STATE MACHINE */
  30
  31 /* substate handler of the config-fsm to handle the cases where we want
  32  * to wait for transmit completion before changing the port configuration
  33  */
  34
  35 static int sirdev_tx_complete_fsm(struct sir_dev *dev)
  36 {
  37         struct sir_fsm *fsm = &dev->fsm;
  38         unsigned next_state, delay;
  39         unsigned bytes_left;
  40
  41         do {
  42                 next_state = fsm->substate;     /* default: stay in current substate */
  43                 delay = 0;
  44
  45                 switch(fsm->substate) {
  46
  47                 case SIRDEV_STATE_WAIT_XMIT:
  48                         if (dev->drv->chars_in_buffer)
  49                                 bytes_left = dev->drv->chars_in_buffer(dev);
  50                         else
  51                                 bytes_left = 0;
  52                         if (!bytes_left) {
  53                                 next_state = SIRDEV_STATE_WAIT_UNTIL_SENT;
  54                                 break;
  55                         }
  56
  57                         if (dev->speed > 115200)
  58                                 delay = (bytes_left*8*10000) / (dev->speed/100);
  59                         else if (dev->speed > 0)
  60                                 delay = (bytes_left*10*10000) / (dev->speed/100);
  61                         else
  62                                 delay = 0;
  63                         /* expected delay (usec) until remaining bytes are sent */
  64                         if (delay < 100) {
  65                                 udelay(delay);
  66                                 delay = 0;
  67                                 break;
  68                         }
  69                         /* sleep some longer delay (msec) */
  70                         delay = (delay+999) / 1000;
  71                         break;
  72
  73                 case SIRDEV_STATE_WAIT_UNTIL_SENT:
  74                         /* block until underlaying hardware buffer are empty */
  75                         if (dev->drv->wait_until_sent)
  76                                 dev->drv->wait_until_sent(dev);
  77                         next_state = SIRDEV_STATE_TX_DONE;
  78                         break;
  79
  80                 case SIRDEV_STATE_TX_DONE:
  81                         return 0;
  82
  83                 default:
  84                         IRDA_ERROR("%s - undefined state\n", __func__);
  85                         return -EINVAL;
  86                 }
  87                 fsm->substate = next_state;
  88         } while (delay == 0);
  89         return delay;
  90 }
  91
  92 /*
  93  * Function sirdev_config_fsm
  94  *
  95  * State machine to handle the configuration of the device (and attached dongle, if any).
  96  * This handler is scheduled for execution in kIrDAd context, so we can sleep.
  97  * however, kIrDAd is shared by all sir_dev devices so we better don't sleep there too
  98  * long. Instead, for longer delays we start a timer to reschedule us later.
  99  * On entry, fsm->sem is always locked and the netdev xmit queue stopped.
 100  * Both must be unlocked/restarted on completion - but only on final exit.
 101  */
 102
 103 static void sirdev_config_fsm(struct work_struct *work)
 104 {
 105         struct sir_dev *dev = container_of(work, struct sir_dev, fsm.work.work);
 106         struct sir_fsm *fsm = &dev->fsm;
 107         int next_state;
 108         int ret = -1;
 109         unsigned delay;
 110
 111         IRDA_DEBUG(2, "%s(), <%ld>\n", __func__, jiffies);
 112
 113         do {
 114                 IRDA_DEBUG(3, "%s - state=0x%04x / substate=0x%04x\n",
 115                         __func__, fsm->state, fsm->substate);
 116
 117                 next_state = fsm->state;
 118                 delay = 0;
 119
 120                 switch(fsm->state) {
 121
 122                 case SIRDEV_STATE_DONGLE_OPEN:
 123                         if (dev->dongle_drv != NULL) {
 124                                 ret = sirdev_put_dongle(dev);
 125                                 if (ret) {
 126                                         fsm->result = -EINVAL;
 127                                         next_state = SIRDEV_STATE_ERROR;
 128                                         break;
 129                                 }
 130                         }
 131
 132                         /* Initialize dongle */
 133                         ret = sirdev_get_dongle(dev, fsm->param);
 134                         if (ret) {
 135                                 fsm->result = ret;
 136                                 next_state = SIRDEV_STATE_ERROR;
 137                                 break;
 138                         }
 139
 140                         /* Dongles are powered through the modem control lines which
 141                          * were just set during open. Before resetting, let's wait for
 142                          * the power to stabilize. This is what some dongle drivers did
 143                          * in open before, while others didn't - should be safe anyway.
 144                          */
 145
 146                         delay = 50;
 147                         fsm->substate = SIRDEV_STATE_DONGLE_RESET;
 148                         next_state = SIRDEV_STATE_DONGLE_RESET;
 149
 150                         fsm->param = 9600;
 151
 152                         break;
 153
 154                 case SIRDEV_STATE_DONGLE_CLOSE:
 155                         /* shouldn't we just treat this as success=? */
 156                         if (dev->dongle_drv == NULL) {
 157                                 fsm->result = -EINVAL;
 158                                 next_state = SIRDEV_STATE_ERROR;
 159                                 break;
 160                         }
 161
 162                         ret = sirdev_put_dongle(dev);
 163                         if (ret) {
 164                                 fsm->result = ret;
 165                                 next_state = SIRDEV_STATE_ERROR;
 166                                 break;
 167                         }
 168                         next_state = SIRDEV_STATE_DONE;
 169                         break;
 170
 171                 case SIRDEV_STATE_SET_DTR_RTS:
 172                         ret = sirdev_set_dtr_rts(dev,
 173                                 (fsm->param&0x02) ? TRUE : FALSE,
 174                                 (fsm->param&0x01) ? TRUE : FALSE);
 175                         next_state = SIRDEV_STATE_DONE;
 176                         break;
 177
 178                 case SIRDEV_STATE_SET_SPEED:
 179                         fsm->substate = SIRDEV_STATE_WAIT_XMIT;
 180                         next_state = SIRDEV_STATE_DONGLE_CHECK;
 181                         break;
 182
 183                 case SIRDEV_STATE_DONGLE_CHECK:
 184                         ret = sirdev_tx_complete_fsm(dev);
 185                         if (ret < 0) {
 186                                 fsm->result = ret;
 187                                 next_state = SIRDEV_STATE_ERROR;
 188                                 break;
 189                         }
 190                         if ((delay=ret) != 0)
 191                                 break;
 192
 193                         if (dev->dongle_drv) {
 194                                 fsm->substate = SIRDEV_STATE_DONGLE_RESET;
 195                                 next_state = SIRDEV_STATE_DONGLE_RESET;
 196                         }
 197                         else {
 198                                 dev->speed = fsm->param;
 199                                 next_state = SIRDEV_STATE_PORT_SPEED;
 200                         }
 201                         break;
 202
 203                 case SIRDEV_STATE_DONGLE_RESET:
 204                         if (dev->dongle_drv->reset) {
 205                                 ret = dev->dongle_drv->reset(dev);
 206                                 if (ret < 0) {
 207                                         fsm->result = ret;
 208                                         next_state = SIRDEV_STATE_ERROR;
 209                                         break;
 210                                 }
 211                         }
 212                         else
 213                                 ret = 0;
 214                         if ((delay=ret) == 0) {
 215                                 /* set serial port according to dongle default speed */
 216                                 if (dev->drv->set_speed)
 217                                         dev->drv->set_speed(dev, dev->speed);
 218                                 fsm->substate = SIRDEV_STATE_DONGLE_SPEED;
 219                                 next_state = SIRDEV_STATE_DONGLE_SPEED;
 220                         }
 221                         break;
 222
 223                 case SIRDEV_STATE_DONGLE_SPEED:
 224                         if (dev->dongle_drv->reset) {
 225                                 ret = dev->dongle_drv->set_speed(dev, fsm->param);
 226                                 if (ret < 0) {
 227                                         fsm->result = ret;
 228                                         next_state = SIRDEV_STATE_ERROR;
 229                                         break;
 230                                 }
 231                         }
 232                         else
 233                                 ret = 0;
 234                         if ((delay=ret) == 0)
 235                                 next_state = SIRDEV_STATE_PORT_SPEED;
 236                         break;
 237
 238                 case SIRDEV_STATE_PORT_SPEED:
 239                         /* Finally we are ready to change the serial port speed */
 240                         if (dev->drv->set_speed)
 241                                 dev->drv->set_speed(dev, dev->speed);
 242                         dev->new_speed = 0;
 243                         next_state = SIRDEV_STATE_DONE;
 244                         break;
 245
 246                 case SIRDEV_STATE_DONE:
 247                         /* Signal network layer so it can send more frames */
 248                         netif_wake_queue(dev->netdev);
 249                         next_state = SIRDEV_STATE_COMPLETE;
 250                         break;
 251
 252                 default:
 253                         IRDA_ERROR("%s - undefined state\n", __func__);
 254                         fsm->result = -EINVAL;
 255                         /* fall thru */
 256
 257                 case SIRDEV_STATE_ERROR:
 258                         IRDA_ERROR("%s - error: %d\n", __func__, fsm->result);
 259
 260                         netif_wake_queue(dev->netdev);
 261                         /* fall thru */
 262
 263                 case SIRDEV_STATE_COMPLETE:
 264                         /* config change finished, so we are not busy any longer */
 265                         sirdev_enable_rx(dev);
 266                         up(&fsm->sem);
 267                         return;
 268                 }
 269                 fsm->state = next_state;
 270         } while(!delay);
 271
 272         queue_delayed_work(irda_sir_wq, &fsm->work, msecs_to_jiffies(delay));
 273 }
 274
 275 /* schedule some device configuration task for execution by kIrDAd
 276  * on behalf of the above state machine.
 277  * can be called from process or interrupt/tasklet context.
 278  */
 279
 280 int sirdev_schedule_request(struct sir_dev *dev, int initial_state, unsigned param)
 281 {
 282         struct sir_fsm *fsm = &dev->fsm;
 283
 284         IRDA_DEBUG(2, "%s - state=0x%04x / param=%u\n", __func__,
 285                         initial_state, param);
 286
 287         if (down_trylock(&fsm->sem)) {
 288                 if (in_interrupt()  ||  in_atomic()  ||  irqs_disabled()) {
 289                         IRDA_DEBUG(1, "%s(), state machine busy!\n", __func__);
 290                         return -EWOULDBLOCK;
 291                 } else
 292                         down(&fsm->sem);
 293         }
 294
 295         if (fsm->state == SIRDEV_STATE_DEAD) {
 296                 /* race with sirdev_close should never happen */
 297                 IRDA_ERROR("%s(), instance staled!\n", __func__);
 298                 up(&fsm->sem);
 299                 return -ESTALE;         /* or better EPIPE? */
 300         }
 301
 302         netif_stop_queue(dev->netdev);
 303         atomic_set(&dev->enable_rx, 0);
 304
 305         fsm->state = initial_state;
 306         fsm->param = param;
 307         fsm->result = 0;
 308
 309         INIT_DELAYED_WORK(&fsm->work, sirdev_config_fsm);
 310         queue_delayed_work(irda_sir_wq, &fsm->work, 0);
 311         return 0;
 312 }
 313
 314
 315 /***************************************************************************/
 316
 317 void sirdev_enable_rx(struct sir_dev *dev)
 318 {
 319         if (unlikely(atomic_read(&dev->enable_rx)))
 320                 return;
 321
 322         /* flush rx-buffer - should also help in case of problems with echo cancelation */
 323         dev->rx_buff.data = dev->rx_buff.head;
 324         dev->rx_buff.len = 0;
 325         dev->rx_buff.in_frame = FALSE;
 326         dev->rx_buff.state = OUTSIDE_FRAME;
 327         atomic_set(&dev->enable_rx, 1);
 328 }
 329
 330 static int sirdev_is_receiving(struct sir_dev *dev)
 331 {
 332         if (!atomic_read(&dev->enable_rx))
 333                 return 0;
 334
 335         return (dev->rx_buff.state != OUTSIDE_FRAME);
 336 }
 337
 338 int sirdev_set_dongle(struct sir_dev *dev, IRDA_DONGLE type)
 339 {
 340         int err;
 341
 342         IRDA_DEBUG(3, "%s : requesting dongle %d.\n", __func__, type);
 343
 344         err = sirdev_schedule_dongle_open(dev, type);
 345         if (unlikely(err))
 346                 return err;
 347         down(&dev->fsm.sem);            /* block until config change completed */
 348         err = dev->fsm.result;
 349         up(&dev->fsm.sem);
 350         return err;
 351 }
 352 EXPORT_SYMBOL(sirdev_set_dongle);
 353
 354 /* used by dongle drivers for dongle programming */
 355
 356 int sirdev_raw_write(struct sir_dev *dev, const char *buf, int len)
 357 {
 358         unsigned long flags;
 359         int ret;
 360
 361         if (unlikely(len > dev->tx_buff.truesize))
 362                 return -ENOSPC;
 363
 364         spin_lock_irqsave(&dev->tx_lock, flags);        /* serialize with other tx operations */
 365         while (dev->tx_buff.len > 0) {                  /* wait until tx idle */
 366                 spin_unlock_irqrestore(&dev->tx_lock, flags);
 367                 msleep(10);
 368                 spin_lock_irqsave(&dev->tx_lock, flags);
 369         }
 370
 371         dev->tx_buff.data = dev->tx_buff.head;
 372         memcpy(dev->tx_buff.data, buf, len);
 373         dev->tx_buff.len = len;
 374
 375         ret = dev->drv->do_write(dev, dev->tx_buff.data, dev->tx_buff.len);
 376         if (ret > 0) {
 377                 IRDA_DEBUG(3, "%s(), raw-tx started\n", __func__);
 378
 379                 dev->tx_buff.data += ret;
 380                 dev->tx_buff.len -= ret;
 381                 dev->raw_tx = 1;
 382                 ret = len;              /* all data is going to be sent */
 383         }
 384         spin_unlock_irqrestore(&dev->tx_lock, flags);
 385         return ret;
 386 }
 387 EXPORT_SYMBOL(sirdev_raw_write);
 388
 389 /* seems some dongle drivers may need this */
 390
 391 int sirdev_raw_read(struct sir_dev *dev, char *buf, int len)
 392 {
 393         int count;
 394
 395         if (atomic_read(&dev->enable_rx))
 396                 return -EIO;            /* fail if we expect irda-frames */
 397
 398         count = (len < dev->rx_buff.len) ? len : dev->rx_buff.len;
 399
 400         if (count > 0) {
 401                 memcpy(buf, dev->rx_buff.data, count);
 402                 dev->rx_buff.data += count;
 403                 dev->rx_buff.len -= count;
 404         }
 405
 406         /* remaining stuff gets flushed when re-enabling normal rx */
 407
 408         return count;
 409 }
 410 EXPORT_SYMBOL(sirdev_raw_read);
 411
 412 int sirdev_set_dtr_rts(struct sir_dev *dev, int dtr, int rts)
 413 {
 414         int ret = -ENXIO;
 415         if (dev->drv->set_dtr_rts)
 416                 ret =  dev->drv->set_dtr_rts(dev, dtr, rts);
 417         return ret;
 418 }
 419 EXPORT_SYMBOL(sirdev_set_dtr_rts);
 420
 421 /**********************************************************************/
 422
 423 /* called from client driver - likely with bh-context - to indicate
 424  * it made some progress with transmission. Hence we send the next
 425  * chunk, if any, or complete the skb otherwise
 426  */
 427
 428 void sirdev_write_complete(struct sir_dev *dev)
 429 {
 430         unsigned long flags;
 431         struct sk_buff *skb;
 432         int actual = 0;
 433         int err;
 434
 435         spin_lock_irqsave(&dev->tx_lock, flags);
 436
 437         IRDA_DEBUG(3, "%s() - dev->tx_buff.len = %d\n",
 438                    __func__, dev->tx_buff.len);
 439
 440         if (likely(dev->tx_buff.len > 0))  {
 441                 /* Write data left in transmit buffer */
 442                 actual = dev->drv->do_write(dev, dev->tx_buff.data, dev->tx_buff.len);
 443
 444                 if (likely(actual>0)) {
 445                         dev->tx_buff.data += actual;
 446                         dev->tx_buff.len  -= actual;
 447                 }
 448                 else if (unlikely(actual<0)) {
 449                         /* could be dropped later when we have tx_timeout to recover */
 450                         IRDA_ERROR("%s: drv->do_write failed (%d)\n",
 451                                    __func__, actual);
 452                         if ((skb=dev->tx_skb) != NULL) {
 453                                 dev->tx_skb = NULL;
 454                                 dev_kfree_skb_any(skb);
 455                                 dev->netdev->stats.tx_errors++;
 456                                 dev->netdev->stats.tx_dropped++;
 457                         }
 458                         dev->tx_buff.len = 0;
 459                 }
 460                 if (dev->tx_buff.len > 0)
 461                         goto done;      /* more data to send later */
 462         }
 463
 464         if (unlikely(dev->raw_tx != 0)) {
 465                 /* in raw mode we are just done now after the buffer was sent
 466                  * completely. Since this was requested by some dongle driver
 467                  * running under the control of the irda-thread we must take
 468                  * care here not to re-enable the queue. The queue will be
 469                  * restarted when the irda-thread has completed the request.
 470                  */
 471
 472                 IRDA_DEBUG(3, "%s(), raw-tx done\n", __func__);
 473                 dev->raw_tx = 0;
 474                 goto done;      /* no post-frame handling in raw mode */
 475         }
 476
 477         /* we have finished now sending this skb.
 478          * update statistics and free the skb.
 479          * finally we check and trigger a pending speed change, if any.
 480          * if not we switch to rx mode and wake the queue for further
 481          * packets.
 482          * note the scheduled speed request blocks until the lower
 483          * client driver and the corresponding hardware has really
 484          * finished sending all data (xmit fifo drained f.e.)
 485          * before the speed change gets finally done and the queue
 486          * re-activated.
 487          */
 488
 489         IRDA_DEBUG(5, "%s(), finished with frame!\n", __func__);
 490
 491         if ((skb=dev->tx_skb) != NULL) {
 492                 dev->tx_skb = NULL;
 493                 dev->netdev->stats.tx_packets++;
 494                 dev->netdev->stats.tx_bytes += skb->len;
 495                 dev_kfree_skb_any(skb);
 496         }
 497
 498         if (unlikely(dev->new_speed > 0)) {
 499                 IRDA_DEBUG(5, "%s(), Changing speed!\n", __func__);
 500                 err = sirdev_schedule_speed(dev, dev->new_speed);
 501                 if (unlikely(err)) {
 502                         /* should never happen
 503                          * forget the speed change and hope the stack recovers
 504                          */
 505                         IRDA_ERROR("%s - schedule speed change failed: %d\n",
 506                                    __func__, err);
 507                         netif_wake_queue(dev->netdev);
 508                 }
 509                 /* else: success
 510                  *      speed change in progress now
 511                  *      on completion dev->new_speed gets cleared,
 512                  *      rx-reenabled and the queue restarted
 513                  */
 514         }
 515         else {
 516                 sirdev_enable_rx(dev);
 517                 netif_wake_queue(dev->netdev);
 518         }
 519
 520 done:
 521         spin_unlock_irqrestore(&dev->tx_lock, flags);
 522 }
 523 EXPORT_SYMBOL(sirdev_write_complete);
 524
 525 /* called from client driver - likely with bh-context - to give us
 526  * some more received bytes. We put them into the rx-buffer,
 527  * normally unwrapping and building LAP-skb's (unless rx disabled)
 528  */
 529
 530 int sirdev_receive(struct sir_dev *dev, const unsigned char *cp, size_t count)
 531 {
 532         if (!dev || !dev->netdev) {
 533                 IRDA_WARNING("%s(), not ready yet!\n", __func__);
 534                 return -1;
 535         }
 536
 537         if (!dev->irlap) {
 538                 IRDA_WARNING("%s - too early: %p / %zd!\n",
 539                              __func__, cp, count);
 540                 return -1;
 541         }
 542
 543         if (cp==NULL) {
 544                 /* error already at lower level receive
 545                  * just update stats and set media busy
 546                  */
 547                 irda_device_set_media_busy(dev->netdev, TRUE);
 548                 dev->netdev->stats.rx_dropped++;
 549                 IRDA_DEBUG(0, "%s; rx-drop: %zd\n", __func__, count);
 550                 return 0;
 551         }
 552
 553         /* Read the characters into the buffer */
 554         if (likely(atomic_read(&dev->enable_rx))) {
 555                 while (count--)
 556                         /* Unwrap and destuff one byte */
 557                         async_unwrap_char(dev->netdev, &dev->netdev->stats,
 558                                           &dev->rx_buff, *cp++);
 559         } else {
 560                 while (count--) {
 561                         /* rx not enabled: save the raw bytes and never
 562                          * trigger any netif_rx. The received bytes are flushed
 563                          * later when we re-enable rx but might be read meanwhile
 564                          * by the dongle driver.
 565                          */
 566                         dev->rx_buff.data[dev->rx_buff.len++] = *cp++;
 567
 568                         /* What should we do when the buffer is full? */
 569                         if (unlikely(dev->rx_buff.len == dev->rx_buff.truesize))
 570                                 dev->rx_buff.len = 0;
 571                 }
 572         }
 573
 574         return 0;
 575 }
 576 EXPORT_SYMBOL(sirdev_receive);
 577
 578 /**********************************************************************/
 579
 580 /* callbacks from network layer */
 581
 582 static netdev_tx_t sirdev_hard_xmit(struct sk_buff *skb,
 583                                           struct net_device *ndev)
 584 {
 585         struct sir_dev *dev = netdev_priv(ndev);
 586         unsigned long flags;
 587         int actual = 0;
 588         int err;
 589         s32 speed;
 590
 591         IRDA_ASSERT(dev != NULL, return NETDEV_TX_OK;);
 592
 593         netif_stop_queue(ndev);
 594
 595         IRDA_DEBUG(3, "%s(), skb->len = %d\n", __func__, skb->len);
 596
 597         speed = irda_get_next_speed(skb);
 598         if ((speed != dev->speed) && (speed != -1)) {
 599                 if (!skb->len) {
 600                         err = sirdev_schedule_speed(dev, speed);
 601                         if (unlikely(err == -EWOULDBLOCK)) {
 602                                 /* Failed to initiate the speed change, likely the fsm
 603                                  * is still busy (pretty unlikely, but...)
 604                                  * We refuse to accept the skb and return with the queue
 605                                  * stopped so the network layer will retry after the
 606                                  * fsm completes and wakes the queue.
 607                                  */
 608                                  return NETDEV_TX_BUSY;
 609                         }
 610                         else if (unlikely(err)) {
 611                                 /* other fatal error - forget the speed change and
 612                                  * hope the stack will recover somehow
 613                                  */
 614                                  netif_start_queue(ndev);
 615                         }
 616                         /* else: success
 617                          *      speed change in progress now
 618                          *      on completion the queue gets restarted
 619                          */
 620
 621                         dev_kfree_skb_any(skb);
 622                         return NETDEV_TX_OK;
 623                 } else
 624                         dev->new_speed = speed;
 625         }
 626
 627         /* Init tx buffer*/
 628         dev->tx_buff.data = dev->tx_buff.head;
 629
 630         /* Check problems */
 631         if(spin_is_locked(&dev->tx_lock)) {
 632                 IRDA_DEBUG(3, "%s(), write not completed\n", __func__);
 633         }
 634
 635         /* serialize with write completion */
 636         spin_lock_irqsave(&dev->tx_lock, flags);
 637
 638         /* Copy skb to tx_buff while wrapping, stuffing and making CRC */
 639         dev->tx_buff.len = async_wrap_skb(skb, dev->tx_buff.data, dev->tx_buff.truesize);
 640
 641         /* transmission will start now - disable receive.
 642          * if we are just in the middle of an incoming frame,
 643          * treat it as collision. probably it's a good idea to
 644          * reset the rx_buf OUTSIDE_FRAME in this case too?
 645          */
 646         atomic_set(&dev->enable_rx, 0);
 647         if (unlikely(sirdev_is_receiving(dev)))
 648                 dev->netdev->stats.collisions++;
 649
 650         actual = dev->drv->do_write(dev, dev->tx_buff.data, dev->tx_buff.len);
 651
 652         if (likely(actual > 0)) {
 653                 dev->tx_skb = skb;
 654                 dev->tx_buff.data += actual;
 655                 dev->tx_buff.len -= actual;
 656         }
 657         else if (unlikely(actual < 0)) {
 658                 /* could be dropped later when we have tx_timeout to recover */
 659                 IRDA_ERROR("%s: drv->do_write failed (%d)\n",
 660                            __func__, actual);
 661                 dev_kfree_skb_any(skb);
 662                 dev->netdev->stats.tx_errors++;
 663                 dev->netdev->stats.tx_dropped++;
 664                 netif_wake_queue(ndev);
 665         }
 666         spin_unlock_irqrestore(&dev->tx_lock, flags);
 667
 668         return NETDEV_TX_OK;
 669 }
 670
 671 /* called from network layer with rtnl hold */
 672
 673 static int sirdev_ioctl(struct net_device *ndev, struct ifreq *rq, int cmd)
 674 {
 675         struct if_irda_req *irq = (struct if_irda_req *) rq;
 676         struct sir_dev *dev = netdev_priv(ndev);
 677         int ret = 0;
 678
 679         IRDA_ASSERT(dev != NULL, return -1;);
 680
 681         IRDA_DEBUG(3, "%s(), %s, (cmd=0x%X)\n", __func__, ndev->name, cmd);
 682
 683         switch (cmd) {
 684         case SIOCSBANDWIDTH: /* Set bandwidth */
 685                 if (!capable(CAP_NET_ADMIN))
 686                         ret = -EPERM;
 687                 else
 688                         ret = sirdev_schedule_speed(dev, irq->ifr_baudrate);
 689                 /* cannot sleep here for completion
 690                  * we are called from network layer with rtnl hold
 691                  */
 692                 break;
 693
 694         case SIOCSDONGLE: /* Set dongle */
 695                 if (!capable(CAP_NET_ADMIN))
 696                         ret = -EPERM;
 697                 else
 698                         ret = sirdev_schedule_dongle_open(dev, irq->ifr_dongle);
 699                 /* cannot sleep here for completion
 700                  * we are called from network layer with rtnl hold
 701                  */
 702                 break;
 703
 704         case SIOCSMEDIABUSY: /* Set media busy */
 705                 if (!capable(CAP_NET_ADMIN))
 706                         ret = -EPERM;
 707                 else
 708                         irda_device_set_media_busy(dev->netdev, TRUE);
 709                 break;
 710
 711         case SIOCGRECEIVING: /* Check if we are receiving right now */
 712                 irq->ifr_receiving = sirdev_is_receiving(dev);
 713                 break;
 714
 715         case SIOCSDTRRTS:
 716                 if (!capable(CAP_NET_ADMIN))
 717                         ret = -EPERM;
 718                 else
 719                         ret = sirdev_schedule_dtr_rts(dev, irq->ifr_dtr, irq->ifr_rts);
 720                 /* cannot sleep here for completion
 721                  * we are called from network layer with rtnl hold
 722                  */
 723                 break;
 724
 725         case SIOCSMODE:
 726         default:
 727                 ret = -EOPNOTSUPP;
 728         }
 729
 730         return ret;
 731 }
 732
 733 /* ----------------------------------------------------------------------------- */
 734
 735 #define SIRBUF_ALLOCSIZE 4269   /* worst case size of a wrapped IrLAP frame */
 736
 737 static int sirdev_alloc_buffers(struct sir_dev *dev)
 738 {
 739         dev->tx_buff.truesize = SIRBUF_ALLOCSIZE;
 740         dev->rx_buff.truesize = IRDA_SKB_MAX_MTU;
 741
 742         /* Bootstrap ZeroCopy Rx */
 743         dev->rx_buff.skb = __netdev_alloc_skb(dev->netdev, dev->rx_buff.truesize,
 744                                               GFP_KERNEL);
 745         if (dev->rx_buff.skb == NULL)
 746                 return -ENOMEM;
 747         skb_reserve(dev->rx_buff.skb, 1);
 748         dev->rx_buff.head = dev->rx_buff.skb->data;
 749
 750         dev->tx_buff.head = kmalloc(dev->tx_buff.truesize, GFP_KERNEL);
 751         if (dev->tx_buff.head == NULL) {
 752                 kfree_skb(dev->rx_buff.skb);
 753                 dev->rx_buff.skb = NULL;
 754                 dev->rx_buff.head = NULL;
 755                 return -ENOMEM;
 756         }
 757
 758         dev->tx_buff.data = dev->tx_buff.head;
 759         dev->rx_buff.data = dev->rx_buff.head;
 760         dev->tx_buff.len = 0;
 761         dev->rx_buff.len = 0;
 762
 763         dev->rx_buff.in_frame = FALSE;
 764         dev->rx_buff.state = OUTSIDE_FRAME;
 765         return 0;
 766 };
 767
 768 static void sirdev_free_buffers(struct sir_dev *dev)
 769 {
 770         kfree_skb(dev->rx_buff.skb);
 771         kfree(dev->tx_buff.head);
 772         dev->rx_buff.head = dev->tx_buff.head = NULL;
 773         dev->rx_buff.skb = NULL;
 774 }
 775
 776 static int sirdev_open(struct net_device *ndev)
 777 {
 778         struct sir_dev *dev = netdev_priv(ndev);
 779         const struct sir_driver *drv = dev->drv;
 780
 781         if (!drv)
 782                 return -ENODEV;
 783
 784         /* increase the reference count of the driver module before doing serious stuff */
 785         if (!try_module_get(drv->owner))
 786                 return -ESTALE;
 787
 788         IRDA_DEBUG(2, "%s()\n", __func__);
 789
 790         if (sirdev_alloc_buffers(dev))
 791                 goto errout_dec;
 792
 793         if (!dev->drv->start_dev  ||  dev->drv->start_dev(dev))
 794                 goto errout_free;
 795
 796         sirdev_enable_rx(dev);
 797         dev->raw_tx = 0;
 798
 799         netif_start_queue(ndev);
 800         dev->irlap = irlap_open(ndev, &dev->qos, dev->hwname);
 801         if (!dev->irlap)
 802                 goto errout_stop;
 803
 804         netif_wake_queue(ndev);
 805
 806         IRDA_DEBUG(2, "%s - done, speed = %d\n", __func__, dev->speed);
 807
 808         return 0;
 809
 810 errout_stop:
 811         atomic_set(&dev->enable_rx, 0);
 812         if (dev->drv->stop_dev)
 813                 dev->drv->stop_dev(dev);
 814 errout_free:
 815         sirdev_free_buffers(dev);
 816 errout_dec:
 817         module_put(drv->owner);
 818         return -EAGAIN;
 819 }
 820
 821 static int sirdev_close(struct net_device *ndev)
 822 {
 823         struct sir_dev *dev = netdev_priv(ndev);
 824         const struct sir_driver *drv;
 825
 826 //      IRDA_DEBUG(0, "%s\n", __func__);
 827
 828         netif_stop_queue(ndev);
 829
 830         down(&dev->fsm.sem);            /* block on pending config completion */
 831
 832         atomic_set(&dev->enable_rx, 0);
 833
 834         if (unlikely(!dev->irlap))
 835                 goto out;
 836         irlap_close(dev->irlap);
 837         dev->irlap = NULL;
 838
 839         drv = dev->drv;
 840         if (unlikely(!drv  ||  !dev->priv))
 841                 goto out;
 842
 843         if (drv->stop_dev)
 844                 drv->stop_dev(dev);
 845
 846         sirdev_free_buffers(dev);
 847         module_put(drv->owner);
 848
 849 out:
 850         dev->speed = 0;
 851         up(&dev->fsm.sem);
 852         return 0;
 853 }
 854
 855 static const struct net_device_ops sirdev_ops = {
 856         .ndo_start_xmit = sirdev_hard_xmit,
 857         .ndo_open       = sirdev_open,
 858         .ndo_stop       = sirdev_close,
 859         .ndo_do_ioctl   = sirdev_ioctl,
 860 };
 861 /* ----------------------------------------------------------------------------- */
 862
 863 struct sir_dev * sirdev_get_instance(const struct sir_driver *drv, const char *name)
 864 {
 865         struct net_device *ndev;
 866         struct sir_dev *dev;
 867
 868         IRDA_DEBUG(0, "%s - %s\n", __func__, name);
 869
 870         /* instead of adding tests to protect against drv->do_write==NULL
 871          * at several places we refuse to create a sir_dev instance for
 872          * drivers which don't implement do_write.
 873          */
 874         if (!drv ||  !drv->do_write)
 875                 return NULL;
 876
 877         /*
 878          *  Allocate new instance of the device
 879          */
 880         ndev = alloc_irdadev(sizeof(*dev));
 881         if (ndev == NULL) {
 882                 IRDA_ERROR("%s - Can't allocate memory for IrDA control block!\n", __func__);
 883                 goto out;
 884         }
 885         dev = netdev_priv(ndev);
 886
 887         irda_init_max_qos_capabilies(&dev->qos);
 888         dev->qos.baud_rate.bits = IR_9600|IR_19200|IR_38400|IR_57600|IR_115200;
 889         dev->qos.min_turn_time.bits = drv->qos_mtt_bits;
 890         irda_qos_bits_to_value(&dev->qos);
 891
 892         strncpy(dev->hwname, name, sizeof(dev->hwname)-1);
 893
 894         atomic_set(&dev->enable_rx, 0);
 895         dev->tx_skb = NULL;
 896
 897         spin_lock_init(&dev->tx_lock);
 898         init_MUTEX(&dev->fsm.sem);
 899
 900         dev->drv = drv;
 901         dev->netdev = ndev;
 902
 903         /* Override the network functions we need to use */
 904         ndev->netdev_ops = &sirdev_ops;
 905
 906         if (register_netdev(ndev)) {
 907                 IRDA_ERROR("%s(), register_netdev() failed!\n", __func__);
 908                 goto out_freenetdev;
 909         }
 910
 911         return dev;
 912
 913 out_freenetdev:
 914         free_netdev(ndev);
 915 out:
 916         return NULL;
 917 }
 918 EXPORT_SYMBOL(sirdev_get_instance);
 919
 920 int sirdev_put_instance(struct sir_dev *dev)
 921 {
 922         int err = 0;
 923
 924         IRDA_DEBUG(0, "%s\n", __func__);
 925
 926         atomic_set(&dev->enable_rx, 0);
 927
 928         netif_carrier_off(dev->netdev);
 929         netif_device_detach(dev->netdev);
 930
 931         if (dev->dongle_drv)
 932                 err = sirdev_schedule_dongle_close(dev);
 933         if (err)
 934                 IRDA_ERROR("%s - error %d\n", __func__, err);
 935
 936         sirdev_close(dev->netdev);
 937
 938         down(&dev->fsm.sem);
 939         dev->fsm.state = SIRDEV_STATE_DEAD;     /* mark staled */
 940         dev->dongle_drv = NULL;
 941         dev->priv = NULL;
 942         up(&dev->fsm.sem);
 943
 944         /* Remove netdevice */
 945         unregister_netdev(dev->netdev);
 946
 947         free_netdev(dev->netdev);
 948
 949         return 0;
 950 }
 951 EXPORT_SYMBOL(sirdev_put_instance);
 952
 953 static int __init sir_wq_init(void)
 954 {
 955         irda_sir_wq = create_singlethread_workqueue("irda_sir_wq");
 956         if (!irda_sir_wq)
 957                 return -ENOMEM;
 958         return 0;
 959 }
 960
 961 static void __exit sir_wq_exit(void)
 962 {
 963         destroy_workqueue(irda_sir_wq);
 964 }
 965
 966 module_init(sir_wq_init);
 967 module_exit(sir_wq_exit);
 968
 969 MODULE_AUTHOR("Martin Diehl <info@mdiehl.de>");
 970 MODULE_DESCRIPTION("IrDA SIR core");
 971 MODULE_LICENSE("GPL");