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/hardirq.h>
  15 #include <linux/module.h>
  16 #include <linux/kernel.h>
  17 #include <linux/slab.h>
  18 #include <linux/init.h>
  19 #include <linux/delay.h>
  20
  21 #include <net/irda/irda.h>
  22 #include <net/irda/wrapper.h>
  23 #include <net/irda/irda_device.h>
  24
  25 #include "sir-dev.h"
  26
  27
  28 static struct workqueue_struct *irda_sir_wq;
  29
  30 /* STATE MACHINE */
  31
  32 /* substate handler of the config-fsm to handle the cases where we want
  33  * to wait for transmit completion before changing the port configuration
  34  */
  35
  36 static int sirdev_tx_complete_fsm(struct sir_dev *dev)
  37 {
  38         struct sir_fsm *fsm = &dev->fsm;
  39         unsigned next_state, delay;
  40         unsigned bytes_left;
  41
  42         do {
  43                 next_state = fsm->substate;     /* default: stay in current substate */
  44                 delay = 0;
  45
  46                 switch(fsm->substate) {
  47
  48                 case SIRDEV_STATE_WAIT_XMIT:
  49                         if (dev->drv->chars_in_buffer)
  50                                 bytes_left = dev->drv->chars_in_buffer(dev);
  51                         else
  52                                 bytes_left = 0;
  53                         if (!bytes_left) {
  54                                 next_state = SIRDEV_STATE_WAIT_UNTIL_SENT;
  55                                 break;
  56                         }
  57
  58                         if (dev->speed > 115200)
  59                                 delay = (bytes_left*8*10000) / (dev->speed/100);
  60                         else if (dev->speed > 0)
  61                                 delay = (bytes_left*10*10000) / (dev->speed/100);
  62                         else
  63                                 delay = 0;
  64                         /* expected delay (usec) until remaining bytes are sent */
  65                         if (delay < 100) {
  66                                 udelay(delay);
  67                                 delay = 0;
  68                                 break;
  69                         }
  70                         /* sleep some longer delay (msec) */
  71                         delay = (delay+999) / 1000;
  72                         break;
  73
  74                 case SIRDEV_STATE_WAIT_UNTIL_SENT:
  75                         /* block until underlaying hardware buffer are empty */
  76                         if (dev->drv->wait_until_sent)
  77                                 dev->drv->wait_until_sent(dev);
  78                         next_state = SIRDEV_STATE_TX_DONE;
  79                         break;
  80
  81                 case SIRDEV_STATE_TX_DONE:
  82                         return 0;
  83
  84                 default:
  85                         IRDA_ERROR("%s - undefined state\n", __func__);
  86                         return -EINVAL;
  87                 }
  88                 fsm->substate = next_state;
  89         } while (delay == 0);
  90         return delay;
  91 }
  92
  93 /*
  94  * Function sirdev_config_fsm
  95  *
  96  * State machine to handle the configuration of the device (and attached dongle, if any).
  97  * This handler is scheduled for execution in kIrDAd context, so we can sleep.
  98  * however, kIrDAd is shared by all sir_dev devices so we better don't sleep there too
  99  * long. Instead, for longer delays we start a timer to reschedule us later.
 100  * On entry, fsm->sem is always locked and the netdev xmit queue stopped.
 101  * Both must be unlocked/restarted on completion - but only on final exit.
 102  */
 103
 104 static void sirdev_config_fsm(struct work_struct *work)
 105 {
 106         struct sir_dev *dev = container_of(work, struct sir_dev, fsm.work.work);
 107         struct sir_fsm *fsm = &dev->fsm;
 108         int next_state;
 109         int ret = -1;
 110         unsigned delay;
 111
 112         IRDA_DEBUG(2, "%s(), <%ld>\n", __func__, jiffies);
 113
 114         do {
 115                 IRDA_DEBUG(3, "%s - state=0x%04x / substate=0x%04x\n",
 116                         __func__, fsm->state, fsm->substate);
 117
 118                 next_state = fsm->state;
 119                 delay = 0;
 120
 121                 switch(fsm->state) {
 122
 123                 case SIRDEV_STATE_DONGLE_OPEN:
 124                         if (dev->dongle_drv != NULL) {
 125                                 ret = sirdev_put_dongle(dev);
 126                                 if (ret) {
 127                                         fsm->result = -EINVAL;
 128                                         next_state = SIRDEV_STATE_ERROR;
 129                                         break;
 130                                 }
 131                         }
 132
 133                         /* Initialize dongle */
 134                         ret = sirdev_get_dongle(dev, fsm->param);
 135                         if (ret) {
 136                                 fsm->result = ret;
 137                                 next_state = SIRDEV_STATE_ERROR;
 138                                 break;
 139                         }
 140
 141                         /* Dongles are powered through the modem control lines which
 142                          * were just set during open. Before resetting, let's wait for
 143                          * the power to stabilize. This is what some dongle drivers did
 144                          * in open before, while others didn't - should be safe anyway.
 145                          */
 146
 147                         delay = 50;
 148                         fsm->substate = SIRDEV_STATE_DONGLE_RESET;
 149                         next_state = SIRDEV_STATE_DONGLE_RESET;
 150
 151                         fsm->param = 9600;
 152
 153                         break;
 154
 155                 case SIRDEV_STATE_DONGLE_CLOSE:
 156                         /* shouldn't we just treat this as success=? */
 157                         if (dev->dongle_drv == NULL) {
 158                                 fsm->result = -EINVAL;
 159                                 next_state = SIRDEV_STATE_ERROR;
 160                                 break;
 161                         }
 162
 163                         ret = sirdev_put_dongle(dev);
 164                         if (ret) {
 165                                 fsm->result = ret;
 166                                 next_state = SIRDEV_STATE_ERROR;
 167                                 break;
 168                         }
 169                         next_state = SIRDEV_STATE_DONE;
 170                         break;
 171
 172                 case SIRDEV_STATE_SET_DTR_RTS:
 173                         ret = sirdev_set_dtr_rts(dev,
 174                                 (fsm->param&0x02) ? TRUE : FALSE,
 175                                 (fsm->param&0x01) ? TRUE : FALSE);
 176                         next_state = SIRDEV_STATE_DONE;
 177                         break;
 178
 179                 case SIRDEV_STATE_SET_SPEED:
 180                         fsm->substate = SIRDEV_STATE_WAIT_XMIT;
 181                         next_state = SIRDEV_STATE_DONGLE_CHECK;
 182                         break;
 183
 184                 case SIRDEV_STATE_DONGLE_CHECK:
 185                         ret = sirdev_tx_complete_fsm(dev);
 186                         if (ret < 0) {
 187                                 fsm->result = ret;
 188                                 next_state = SIRDEV_STATE_ERROR;
 189                                 break;
 190                         }
 191                         if ((delay=ret) != 0)
 192                                 break;
 193
 194                         if (dev->dongle_drv) {
 195                                 fsm->substate = SIRDEV_STATE_DONGLE_RESET;
 196                                 next_state = SIRDEV_STATE_DONGLE_RESET;
 197                         }
 198                         else {
 199                                 dev->speed = fsm->param;
 200                                 next_state = SIRDEV_STATE_PORT_SPEED;
 201                         }
 202                         break;
 203
 204                 case SIRDEV_STATE_DONGLE_RESET:
 205                         if (dev->dongle_drv->reset) {
 206                                 ret = dev->dongle_drv->reset(dev);
 207                                 if (ret < 0) {
 208                                         fsm->result = ret;
 209                                         next_state = SIRDEV_STATE_ERROR;
 210                                         break;
 211                                 }
 212                         }
 213                         else
 214                                 ret = 0;
 215                         if ((delay=ret) == 0) {
 216                                 /* set serial port according to dongle default speed */
 217                                 if (dev->drv->set_speed)
 218                                         dev->drv->set_speed(dev, dev->speed);
 219                                 fsm->substate = SIRDEV_STATE_DONGLE_SPEED;
 220                                 next_state = SIRDEV_STATE_DONGLE_SPEED;
 221                         }
 222                         break;
 223
 224                 case SIRDEV_STATE_DONGLE_SPEED:
 225                         if (dev->dongle_drv->set_speed) {
 226                                 ret = dev->dongle_drv->set_speed(dev, fsm->param);
 227                                 if (ret < 0) {
 228                                         fsm->result = ret;
 229                                         next_state = SIRDEV_STATE_ERROR;
 230                                         break;
 231                                 }
 232                         }
 233                         else
 234                                 ret = 0;
 235                         if ((delay=ret) == 0)
 236                                 next_state = SIRDEV_STATE_PORT_SPEED;
 237                         break;
 238
 239                 case SIRDEV_STATE_PORT_SPEED:
 240                         /* Finally we are ready to change the serial port speed */
 241                         if (dev->drv->set_speed)
 242                                 dev->drv->set_speed(dev, dev->speed);
 243                         dev->new_speed = 0;
 244                         next_state = SIRDEV_STATE_DONE;
 245                         break;
 246
 247                 case SIRDEV_STATE_DONE:
 248                         /* Signal network layer so it can send more frames */
 249                         netif_wake_queue(dev->netdev);
 250                         next_state = SIRDEV_STATE_COMPLETE;
 251                         break;
 252
 253                 default:
 254                         IRDA_ERROR("%s - undefined state\n", __func__);
 255                         fsm->result = -EINVAL;
 256                         /* fall thru */
 257
 258                 case SIRDEV_STATE_ERROR:
 259                         IRDA_ERROR("%s - error: %d\n", __func__, fsm->result);
 260
 261 #if 0   /* don't enable this before we have netdev->tx_timeout to recover */
 262                         netif_stop_queue(dev->netdev);
 263 #else
 264                         netif_wake_queue(dev->netdev);
 265 #endif
 266                         /* fall thru */
 267
 268                 case SIRDEV_STATE_COMPLETE:
 269                         /* config change finished, so we are not busy any longer */
 270                         sirdev_enable_rx(dev);
 271                         up(&fsm->sem);
 272                         return;
 273                 }
 274                 fsm->state = next_state;
 275         } while(!delay);
 276
 277         queue_delayed_work(irda_sir_wq, &fsm->work, msecs_to_jiffies(delay));
 278 }
 279
 280 /* schedule some device configuration task for execution by kIrDAd
 281  * on behalf of the above state machine.
 282  * can be called from process or interrupt/tasklet context.
 283  */
 284
 285 int sirdev_schedule_request(struct sir_dev *dev, int initial_state, unsigned param)
 286 {
 287         struct sir_fsm *fsm = &dev->fsm;
 288
 289         IRDA_DEBUG(2, "%s - state=0x%04x / param=%u\n", __func__,
 290                         initial_state, param);
 291
 292         if (down_trylock(&fsm->sem)) {
 293                 if (in_interrupt()  ||  in_atomic()  ||  irqs_disabled()) {
 294                         IRDA_DEBUG(1, "%s(), state machine busy!\n", __func__);
 295                         return -EWOULDBLOCK;
 296                 } else
 297                         down(&fsm->sem);
 298         }
 299
 300         if (fsm->state == SIRDEV_STATE_DEAD) {
 301                 /* race with sirdev_close should never happen */
 302                 IRDA_ERROR("%s(), instance staled!\n", __func__);
 303                 up(&fsm->sem);
 304                 return -ESTALE;         /* or better EPIPE? */
 305         }
 306
 307         netif_stop_queue(dev->netdev);
 308         atomic_set(&dev->enable_rx, 0);
 309
 310         fsm->state = initial_state;
 311         fsm->param = param;
 312         fsm->result = 0;
 313
 314         INIT_DELAYED_WORK(&fsm->work, sirdev_config_fsm);
 315         queue_delayed_work(irda_sir_wq, &fsm->work, 0);
 316         return 0;
 317 }
 318
 319
 320 /***************************************************************************/
 321
 322 void sirdev_enable_rx(struct sir_dev *dev)
 323 {
 324         if (unlikely(atomic_read(&dev->enable_rx)))
 325                 return;
 326
 327         /* flush rx-buffer - should also help in case of problems with echo cancelation */
 328         dev->rx_buff.data = dev->rx_buff.head;
 329         dev->rx_buff.len = 0;
 330         dev->rx_buff.in_frame = FALSE;
 331         dev->rx_buff.state = OUTSIDE_FRAME;
 332         atomic_set(&dev->enable_rx, 1);
 333 }
 334
 335 static int sirdev_is_receiving(struct sir_dev *dev)
 336 {
 337         if (!atomic_read(&dev->enable_rx))
 338                 return 0;
 339
 340         return dev->rx_buff.state != OUTSIDE_FRAME;
 341 }
 342
 343 int sirdev_set_dongle(struct sir_dev *dev, IRDA_DONGLE type)
 344 {
 345         int err;
 346
 347         IRDA_DEBUG(3, "%s : requesting dongle %d.\n", __func__, type);
 348
 349         err = sirdev_schedule_dongle_open(dev, type);
 350         if (unlikely(err))
 351                 return err;
 352         down(&dev->fsm.sem);            /* block until config change completed */
 353         err = dev->fsm.result;
 354         up(&dev->fsm.sem);
 355         return err;
 356 }
 357 EXPORT_SYMBOL(sirdev_set_dongle);
 358
 359 /* used by dongle drivers for dongle programming */
 360
 361 int sirdev_raw_write(struct sir_dev *dev, const char *buf, int len)
 362 {
 363         unsigned long flags;
 364         int ret;
 365
 366         if (unlikely(len > dev->tx_buff.truesize))
 367                 return -ENOSPC;
 368
 369         spin_lock_irqsave(&dev->tx_lock, flags);        /* serialize with other tx operations */
 370         while (dev->tx_buff.len > 0) {                  /* wait until tx idle */
 371                 spin_unlock_irqrestore(&dev->tx_lock, flags);
 372                 msleep(10);
 373                 spin_lock_irqsave(&dev->tx_lock, flags);
 374         }
 375
 376         dev->tx_buff.data = dev->tx_buff.head;
 377         memcpy(dev->tx_buff.data, buf, len);
 378         dev->tx_buff.len = len;
 379
 380         ret = dev->drv->do_write(dev, dev->tx_buff.data, dev->tx_buff.len);
 381         if (ret > 0) {
 382                 IRDA_DEBUG(3, "%s(), raw-tx started\n", __func__);
 383
 384                 dev->tx_buff.data += ret;
 385                 dev->tx_buff.len -= ret;
 386                 dev->raw_tx = 1;
 387                 ret = len;              /* all data is going to be sent */
 388         }
 389         spin_unlock_irqrestore(&dev->tx_lock, flags);
 390         return ret;
 391 }
 392 EXPORT_SYMBOL(sirdev_raw_write);
 393
 394 /* seems some dongle drivers may need this */
 395
 396 int sirdev_raw_read(struct sir_dev *dev, char *buf, int len)
 397 {
 398         int count;
 399
 400         if (atomic_read(&dev->enable_rx))
 401                 return -EIO;            /* fail if we expect irda-frames */
 402
 403         count = (len < dev->rx_buff.len) ? len : dev->rx_buff.len;
 404
 405         if (count > 0) {
 406                 memcpy(buf, dev->rx_buff.data, count);
 407                 dev->rx_buff.data += count;
 408                 dev->rx_buff.len -= count;
 409         }
 410
 411         /* remaining stuff gets flushed when re-enabling normal rx */
 412
 413         return count;
 414 }
 415 EXPORT_SYMBOL(sirdev_raw_read);
 416
 417 int sirdev_set_dtr_rts(struct sir_dev *dev, int dtr, int rts)
 418 {
 419         int ret = -ENXIO;
 420         if (dev->drv->set_dtr_rts)
 421                 ret =  dev->drv->set_dtr_rts(dev, dtr, rts);
 422         return ret;
 423 }
 424 EXPORT_SYMBOL(sirdev_set_dtr_rts);
 425
 426 /**********************************************************************/
 427
 428 /* called from client driver - likely with bh-context - to indicate
 429  * it made some progress with transmission. Hence we send the next
 430  * chunk, if any, or complete the skb otherwise
 431  */
 432
 433 void sirdev_write_complete(struct sir_dev *dev)
 434 {
 435         unsigned long flags;
 436         struct sk_buff *skb;
 437         int actual = 0;
 438         int err;
 439
 440         spin_lock_irqsave(&dev->tx_lock, flags);
 441
 442         IRDA_DEBUG(3, "%s() - dev->tx_buff.len = %d\n",
 443                    __func__, dev->tx_buff.len);
 444
 445         if (likely(dev->tx_buff.len > 0))  {
 446                 /* Write data left in transmit buffer */
 447                 actual = dev->drv->do_write(dev, dev->tx_buff.data, dev->tx_buff.len);
 448
 449                 if (likely(actual>0)) {
 450                         dev->tx_buff.data += actual;
 451                         dev->tx_buff.len  -= actual;
 452                 }
 453                 else if (unlikely(actual<0)) {
 454                         /* could be dropped later when we have tx_timeout to recover */
 455                         IRDA_ERROR("%s: drv->do_write failed (%d)\n",
 456                                    __func__, actual);
 457                         if ((skb=dev->tx_skb) != NULL) {
 458                                 dev->tx_skb = NULL;
 459                                 dev_kfree_skb_any(skb);
 460                                 dev->netdev->stats.tx_errors++;
 461                                 dev->netdev->stats.tx_dropped++;
 462                         }
 463                         dev->tx_buff.len = 0;
 464                 }
 465                 if (dev->tx_buff.len > 0)
 466                         goto done;      /* more data to send later */
 467         }
 468
 469         if (unlikely(dev->raw_tx != 0)) {
 470                 /* in raw mode we are just done now after the buffer was sent
 471                  * completely. Since this was requested by some dongle driver
 472                  * running under the control of the irda-thread we must take
 473                  * care here not to re-enable the queue. The queue will be
 474                  * restarted when the irda-thread has completed the request.
 475                  */
 476
 477                 IRDA_DEBUG(3, "%s(), raw-tx done\n", __func__);
 478                 dev->raw_tx = 0;
 479                 goto done;      /* no post-frame handling in raw mode */
 480         }
 481
 482         /* we have finished now sending this skb.
 483          * update statistics and free the skb.
 484          * finally we check and trigger a pending speed change, if any.
 485          * if not we switch to rx mode and wake the queue for further
 486          * packets.
 487          * note the scheduled speed request blocks until the lower
 488          * client driver and the corresponding hardware has really
 489          * finished sending all data (xmit fifo drained f.e.)
 490          * before the speed change gets finally done and the queue
 491          * re-activated.
 492          */
 493
 494         IRDA_DEBUG(5, "%s(), finished with frame!\n", __func__);
 495
 496         if ((skb=dev->tx_skb) != NULL) {
 497                 dev->tx_skb = NULL;
 498                 dev->netdev->stats.tx_packets++;
 499                 dev->netdev->stats.tx_bytes += skb->len;
 500                 dev_kfree_skb_any(skb);
 501         }
 502
 503         if (unlikely(dev->new_speed > 0)) {
 504                 IRDA_DEBUG(5, "%s(), Changing speed!\n", __func__);
 505                 err = sirdev_schedule_speed(dev, dev->new_speed);
 506                 if (unlikely(err)) {
 507                         /* should never happen
 508                          * forget the speed change and hope the stack recovers
 509                          */
 510                         IRDA_ERROR("%s - schedule speed change failed: %d\n",
 511                                    __func__, err);
 512                         netif_wake_queue(dev->netdev);
 513                 }
 514                 /* else: success
 515                  *      speed change in progress now
 516                  *      on completion dev->new_speed gets cleared,
 517                  *      rx-reenabled and the queue restarted
 518                  */
 519         }
 520         else {
 521                 sirdev_enable_rx(dev);
 522                 netif_wake_queue(dev->netdev);
 523         }
 524
 525 done:
 526         spin_unlock_irqrestore(&dev->tx_lock, flags);
 527 }
 528 EXPORT_SYMBOL(sirdev_write_complete);
 529
 530 /* called from client driver - likely with bh-context - to give us
 531  * some more received bytes. We put them into the rx-buffer,
 532  * normally unwrapping and building LAP-skb's (unless rx disabled)
 533  */
 534
 535 int sirdev_receive(struct sir_dev *dev, const unsigned char *cp, size_t count)
 536 {
 537         if (!dev || !dev->netdev) {
 538                 IRDA_WARNING("%s(), not ready yet!\n", __func__);
 539                 return -1;
 540         }
 541
 542         if (!dev->irlap) {
 543                 IRDA_WARNING("%s - too early: %p / %zd!\n",
 544                              __func__, cp, count);
 545                 return -1;
 546         }
 547
 548         if (cp==NULL) {
 549                 /* error already at lower level receive
 550                  * just update stats and set media busy
 551                  */
 552                 irda_device_set_media_busy(dev->netdev, TRUE);
 553                 dev->netdev->stats.rx_dropped++;
 554                 IRDA_DEBUG(0, "%s; rx-drop: %zd\n", __func__, count);
 555                 return 0;
 556         }
 557
 558         /* Read the characters into the buffer */
 559         if (likely(atomic_read(&dev->enable_rx))) {
 560                 while (count--)
 561                         /* Unwrap and destuff one byte */
 562                         async_unwrap_char(dev->netdev, &dev->netdev->stats,
 563                                           &dev->rx_buff, *cp++);
 564         } else {
 565                 while (count--) {
 566                         /* rx not enabled: save the raw bytes and never
 567                          * trigger any netif_rx. The received bytes are flushed
 568                          * later when we re-enable rx but might be read meanwhile
 569                          * by the dongle driver.
 570                          */
 571                         dev->rx_buff.data[dev->rx_buff.len++] = *cp++;
 572
 573                         /* What should we do when the buffer is full? */
 574                         if (unlikely(dev->rx_buff.len == dev->rx_buff.truesize))
 575                                 dev->rx_buff.len = 0;
 576                 }
 577         }
 578
 579         return 0;
 580 }
 581 EXPORT_SYMBOL(sirdev_receive);
 582
 583 /**********************************************************************/
 584
 585 /* callbacks from network layer */
 586
 587 static netdev_tx_t sirdev_hard_xmit(struct sk_buff *skb,
 588                                           struct net_device *ndev)
 589 {
 590         struct sir_dev *dev = netdev_priv(ndev);
 591         unsigned long flags;
 592         int actual = 0;
 593         int err;
 594         s32 speed;
 595
 596         IRDA_ASSERT(dev != NULL, return NETDEV_TX_OK;);
 597
 598         netif_stop_queue(ndev);
 599
 600         IRDA_DEBUG(3, "%s(), skb->len = %d\n", __func__, skb->len);
 601
 602         speed = irda_get_next_speed(skb);
 603         if ((speed != dev->speed) && (speed != -1)) {
 604                 if (!skb->len) {
 605                         err = sirdev_schedule_speed(dev, speed);
 606                         if (unlikely(err == -EWOULDBLOCK)) {
 607                                 /* Failed to initiate the speed change, likely the fsm
 608                                  * is still busy (pretty unlikely, but...)
 609                                  * We refuse to accept the skb and return with the queue
 610                                  * stopped so the network layer will retry after the
 611                                  * fsm completes and wakes the queue.
 612                                  */
 613                                  return NETDEV_TX_BUSY;
 614                         }
 615                         else if (unlikely(err)) {
 616                                 /* other fatal error - forget the speed change and
 617                                  * hope the stack will recover somehow
 618                                  */
 619                                  netif_start_queue(ndev);
 620                         }
 621                         /* else: success
 622                          *      speed change in progress now
 623                          *      on completion the queue gets restarted
 624                          */
 625
 626                         dev_kfree_skb_any(skb);
 627                         return NETDEV_TX_OK;
 628                 } else
 629                         dev->new_speed = speed;
 630         }
 631
 632         /* Init tx buffer*/
 633         dev->tx_buff.data = dev->tx_buff.head;
 634
 635         /* Check problems */
 636         if(spin_is_locked(&dev->tx_lock)) {
 637                 IRDA_DEBUG(3, "%s(), write not completed\n", __func__);
 638         }
 639
 640         /* serialize with write completion */
 641         spin_lock_irqsave(&dev->tx_lock, flags);
 642
 643         /* Copy skb to tx_buff while wrapping, stuffing and making CRC */
 644         dev->tx_buff.len = async_wrap_skb(skb, dev->tx_buff.data, dev->tx_buff.truesize);
 645
 646         /* transmission will start now - disable receive.
 647          * if we are just in the middle of an incoming frame,
 648          * treat it as collision. probably it's a good idea to
 649          * reset the rx_buf OUTSIDE_FRAME in this case too?
 650          */
 651         atomic_set(&dev->enable_rx, 0);
 652         if (unlikely(sirdev_is_receiving(dev)))
 653                 dev->netdev->stats.collisions++;
 654
 655         actual = dev->drv->do_write(dev, dev->tx_buff.data, dev->tx_buff.len);
 656
 657         if (likely(actual > 0)) {
 658                 dev->tx_skb = skb;
 659                 dev->tx_buff.data += actual;
 660                 dev->tx_buff.len -= actual;
 661         }
 662         else if (unlikely(actual < 0)) {
 663                 /* could be dropped later when we have tx_timeout to recover */
 664                 IRDA_ERROR("%s: drv->do_write failed (%d)\n",
 665                            __func__, actual);
 666                 dev_kfree_skb_any(skb);
 667                 dev->netdev->stats.tx_errors++;
 668                 dev->netdev->stats.tx_dropped++;
 669                 netif_wake_queue(ndev);
 670         }
 671         spin_unlock_irqrestore(&dev->tx_lock, flags);
 672
 673         return NETDEV_TX_OK;
 674 }
 675
 676 /* called from network layer with rtnl hold */
 677
 678 static int sirdev_ioctl(struct net_device *ndev, struct ifreq *rq, int cmd)
 679 {
 680         struct if_irda_req *irq = (struct if_irda_req *) rq;
 681         struct sir_dev *dev = netdev_priv(ndev);
 682         int ret = 0;
 683
 684         IRDA_ASSERT(dev != NULL, return -1;);
 685
 686         IRDA_DEBUG(3, "%s(), %s, (cmd=0x%X)\n", __func__, ndev->name, cmd);
 687
 688         switch (cmd) {
 689         case SIOCSBANDWIDTH: /* Set bandwidth */
 690                 if (!capable(CAP_NET_ADMIN))
 691                         ret = -EPERM;
 692                 else
 693                         ret = sirdev_schedule_speed(dev, irq->ifr_baudrate);
 694                 /* cannot sleep here for completion
 695                  * we are called from network layer with rtnl hold
 696                  */
 697                 break;
 698
 699         case SIOCSDONGLE: /* Set dongle */
 700                 if (!capable(CAP_NET_ADMIN))
 701                         ret = -EPERM;
 702                 else
 703                         ret = sirdev_schedule_dongle_open(dev, irq->ifr_dongle);
 704                 /* cannot sleep here for completion
 705                  * we are called from network layer with rtnl hold
 706                  */
 707                 break;
 708
 709         case SIOCSMEDIABUSY: /* Set media busy */
 710                 if (!capable(CAP_NET_ADMIN))
 711                         ret = -EPERM;
 712                 else
 713                         irda_device_set_media_busy(dev->netdev, TRUE);
 714                 break;
 715
 716         case SIOCGRECEIVING: /* Check if we are receiving right now */
 717                 irq->ifr_receiving = sirdev_is_receiving(dev);
 718                 break;
 719
 720         case SIOCSDTRRTS:
 721                 if (!capable(CAP_NET_ADMIN))
 722                         ret = -EPERM;
 723                 else
 724                         ret = sirdev_schedule_dtr_rts(dev, irq->ifr_dtr, irq->ifr_rts);
 725                 /* cannot sleep here for completion
 726                  * we are called from network layer with rtnl hold
 727                  */
 728                 break;
 729
 730         case SIOCSMODE:
 731 #if 0
 732                 if (!capable(CAP_NET_ADMIN))
 733                         ret = -EPERM;
 734                 else
 735                         ret = sirdev_schedule_mode(dev, irq->ifr_mode);
 736                 /* cannot sleep here for completion
 737                  * we are called from network layer with rtnl hold
 738                  */
 739                 break;
 740 #endif
 741         default:
 742                 ret = -EOPNOTSUPP;
 743         }
 744
 745         return ret;
 746 }
 747
 748 /* ----------------------------------------------------------------------------- */
 749
 750 #define SIRBUF_ALLOCSIZE 4269   /* worst case size of a wrapped IrLAP frame */
 751
 752 static int sirdev_alloc_buffers(struct sir_dev *dev)
 753 {
 754         dev->tx_buff.truesize = SIRBUF_ALLOCSIZE;
 755         dev->rx_buff.truesize = IRDA_SKB_MAX_MTU;
 756
 757         /* Bootstrap ZeroCopy Rx */
 758         dev->rx_buff.skb = __netdev_alloc_skb(dev->netdev, dev->rx_buff.truesize,
 759                                               GFP_KERNEL);
 760         if (dev->rx_buff.skb == NULL)
 761                 return -ENOMEM;
 762         skb_reserve(dev->rx_buff.skb, 1);
 763         dev->rx_buff.head = dev->rx_buff.skb->data;
 764
 765         dev->tx_buff.head = kmalloc(dev->tx_buff.truesize, GFP_KERNEL);
 766         if (dev->tx_buff.head == NULL) {
 767                 kfree_skb(dev->rx_buff.skb);
 768                 dev->rx_buff.skb = NULL;
 769                 dev->rx_buff.head = NULL;
 770                 return -ENOMEM;
 771         }
 772
 773         dev->tx_buff.data = dev->tx_buff.head;
 774         dev->rx_buff.data = dev->rx_buff.head;
 775         dev->tx_buff.len = 0;
 776         dev->rx_buff.len = 0;
 777
 778         dev->rx_buff.in_frame = FALSE;
 779         dev->rx_buff.state = OUTSIDE_FRAME;
 780         return 0;
 781 };
 782
 783 static void sirdev_free_buffers(struct sir_dev *dev)
 784 {
 785         kfree_skb(dev->rx_buff.skb);
 786         kfree(dev->tx_buff.head);
 787         dev->rx_buff.head = dev->tx_buff.head = NULL;
 788         dev->rx_buff.skb = NULL;
 789 }
 790
 791 static int sirdev_open(struct net_device *ndev)
 792 {
 793         struct sir_dev *dev = netdev_priv(ndev);
 794         const struct sir_driver *drv = dev->drv;
 795
 796         if (!drv)
 797                 return -ENODEV;
 798
 799         /* increase the reference count of the driver module before doing serious stuff */
 800         if (!try_module_get(drv->owner))
 801                 return -ESTALE;
 802
 803         IRDA_DEBUG(2, "%s()\n", __func__);
 804
 805         if (sirdev_alloc_buffers(dev))
 806                 goto errout_dec;
 807
 808         if (!dev->drv->start_dev  ||  dev->drv->start_dev(dev))
 809                 goto errout_free;
 810
 811         sirdev_enable_rx(dev);
 812         dev->raw_tx = 0;
 813
 814         netif_start_queue(ndev);
 815         dev->irlap = irlap_open(ndev, &dev->qos, dev->hwname);
 816         if (!dev->irlap)
 817                 goto errout_stop;
 818
 819         netif_wake_queue(ndev);
 820
 821         IRDA_DEBUG(2, "%s - done, speed = %d\n", __func__, dev->speed);
 822
 823         return 0;
 824
 825 errout_stop:
 826         atomic_set(&dev->enable_rx, 0);
 827         if (dev->drv->stop_dev)
 828                 dev->drv->stop_dev(dev);
 829 errout_free:
 830         sirdev_free_buffers(dev);
 831 errout_dec:
 832         module_put(drv->owner);
 833         return -EAGAIN;
 834 }
 835
 836 static int sirdev_close(struct net_device *ndev)
 837 {
 838         struct sir_dev *dev = netdev_priv(ndev);
 839         const struct sir_driver *drv;
 840
 841 //      IRDA_DEBUG(0, "%s\n", __func__);
 842
 843         netif_stop_queue(ndev);
 844
 845         down(&dev->fsm.sem);            /* block on pending config completion */
 846
 847         atomic_set(&dev->enable_rx, 0);
 848
 849         if (unlikely(!dev->irlap))
 850                 goto out;
 851         irlap_close(dev->irlap);
 852         dev->irlap = NULL;
 853
 854         drv = dev->drv;
 855         if (unlikely(!drv  ||  !dev->priv))
 856                 goto out;
 857
 858         if (drv->stop_dev)
 859                 drv->stop_dev(dev);
 860
 861         sirdev_free_buffers(dev);
 862         module_put(drv->owner);
 863
 864 out:
 865         dev->speed = 0;
 866         up(&dev->fsm.sem);
 867         return 0;
 868 }
 869
 870 static const struct net_device_ops sirdev_ops = {
 871         .ndo_start_xmit = sirdev_hard_xmit,
 872         .ndo_open       = sirdev_open,
 873         .ndo_stop       = sirdev_close,
 874         .ndo_do_ioctl   = sirdev_ioctl,
 875 };
 876 /* ----------------------------------------------------------------------------- */
 877
 878 struct sir_dev * sirdev_get_instance(const struct sir_driver *drv, const char *name)
 879 {
 880         struct net_device *ndev;
 881         struct sir_dev *dev;
 882
 883         IRDA_DEBUG(0, "%s - %s\n", __func__, name);
 884
 885         /* instead of adding tests to protect against drv->do_write==NULL
 886          * at several places we refuse to create a sir_dev instance for
 887          * drivers which don't implement do_write.
 888          */
 889         if (!drv ||  !drv->do_write)
 890                 return NULL;
 891
 892         /*
 893          *  Allocate new instance of the device
 894          */
 895         ndev = alloc_irdadev(sizeof(*dev));
 896         if (ndev == NULL) {
 897                 IRDA_ERROR("%s - Can't allocate memory for IrDA control block!\n", __func__);
 898                 goto out;
 899         }
 900         dev = netdev_priv(ndev);
 901
 902         irda_init_max_qos_capabilies(&dev->qos);
 903         dev->qos.baud_rate.bits = IR_9600|IR_19200|IR_38400|IR_57600|IR_115200;
 904         dev->qos.min_turn_time.bits = drv->qos_mtt_bits;
 905         irda_qos_bits_to_value(&dev->qos);
 906
 907         strncpy(dev->hwname, name, sizeof(dev->hwname)-1);
 908
 909         atomic_set(&dev->enable_rx, 0);
 910         dev->tx_skb = NULL;
 911
 912         spin_lock_init(&dev->tx_lock);
 913         sema_init(&dev->fsm.sem, 1);
 914
 915         dev->drv = drv;
 916         dev->netdev = ndev;
 917
 918         /* Override the network functions we need to use */
 919         ndev->netdev_ops = &sirdev_ops;
 920
 921         if (register_netdev(ndev)) {
 922                 IRDA_ERROR("%s(), register_netdev() failed!\n", __func__);
 923                 goto out_freenetdev;
 924         }
 925
 926         return dev;
 927
 928 out_freenetdev:
 929         free_netdev(ndev);
 930 out:
 931         return NULL;
 932 }
 933 EXPORT_SYMBOL(sirdev_get_instance);
 934
 935 int sirdev_put_instance(struct sir_dev *dev)
 936 {
 937         int err = 0;
 938
 939         IRDA_DEBUG(0, "%s\n", __func__);
 940
 941         atomic_set(&dev->enable_rx, 0);
 942
 943         netif_carrier_off(dev->netdev);
 944         netif_device_detach(dev->netdev);
 945
 946         if (dev->dongle_drv)
 947                 err = sirdev_schedule_dongle_close(dev);
 948         if (err)
 949                 IRDA_ERROR("%s - error %d\n", __func__, err);
 950
 951         sirdev_close(dev->netdev);
 952
 953         down(&dev->fsm.sem);
 954         dev->fsm.state = SIRDEV_STATE_DEAD;     /* mark staled */
 955         dev->dongle_drv = NULL;
 956         dev->priv = NULL;
 957         up(&dev->fsm.sem);
 958
 959         /* Remove netdevice */
 960         unregister_netdev(dev->netdev);
 961
 962         free_netdev(dev->netdev);
 963
 964         return 0;
 965 }
 966 EXPORT_SYMBOL(sirdev_put_instance);
 967
 968 static int __init sir_wq_init(void)
 969 {
 970         irda_sir_wq = create_singlethread_workqueue("irda_sir_wq");
 971         if (!irda_sir_wq)
 972                 return -ENOMEM;
 973         return 0;
 974 }
 975
 976 static void __exit sir_wq_exit(void)
 977 {
 978         destroy_workqueue(irda_sir_wq);
 979 }
 980
 981 module_init(sir_wq_init);
 982 module_exit(sir_wq_exit);
 983
 984 MODULE_AUTHOR("Martin Diehl <[email protected]>");
 985 MODULE_DESCRIPTION("IrDA SIR core");
 986 MODULE_LICENSE("GPL");