Linux-2.6.12-rc2
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / 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/init.h>
17 #include <linux/smp_lock.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
28 void sirdev_enable_rx(struct sir_dev *dev)
29 {
30 if (unlikely(atomic_read(&dev->enable_rx)))
31 return;
32
33 /* flush rx-buffer - should also help in case of problems with echo cancelation */
34 dev->rx_buff.data = dev->rx_buff.head;
35 dev->rx_buff.len = 0;
36 dev->rx_buff.in_frame = FALSE;
37 dev->rx_buff.state = OUTSIDE_FRAME;
38 atomic_set(&dev->enable_rx, 1);
39 }
40
41 static int sirdev_is_receiving(struct sir_dev *dev)
42 {
43 if (!atomic_read(&dev->enable_rx))
44 return 0;
45
46 return (dev->rx_buff.state != OUTSIDE_FRAME);
47 }
48
49 int sirdev_set_dongle(struct sir_dev *dev, IRDA_DONGLE type)
50 {
51 int err;
52
53 IRDA_DEBUG(3, "%s : requesting dongle %d.\n", __FUNCTION__, type);
54
55 err = sirdev_schedule_dongle_open(dev, type);
56 if (unlikely(err))
57 return err;
58 down(&dev->fsm.sem); /* block until config change completed */
59 err = dev->fsm.result;
60 up(&dev->fsm.sem);
61 return err;
62 }
63
64 /* used by dongle drivers for dongle programming */
65
66 int sirdev_raw_write(struct sir_dev *dev, const char *buf, int len)
67 {
68 unsigned long flags;
69 int ret;
70
71 if (unlikely(len > dev->tx_buff.truesize))
72 return -ENOSPC;
73
74 spin_lock_irqsave(&dev->tx_lock, flags); /* serialize with other tx operations */
75 while (dev->tx_buff.len > 0) { /* wait until tx idle */
76 spin_unlock_irqrestore(&dev->tx_lock, flags);
77 msleep(10);
78 spin_lock_irqsave(&dev->tx_lock, flags);
79 }
80
81 dev->tx_buff.data = dev->tx_buff.head;
82 memcpy(dev->tx_buff.data, buf, len);
83 dev->tx_buff.len = len;
84
85 ret = dev->drv->do_write(dev, dev->tx_buff.data, dev->tx_buff.len);
86 if (ret > 0) {
87 IRDA_DEBUG(3, "%s(), raw-tx started\n", __FUNCTION__);
88
89 dev->tx_buff.data += ret;
90 dev->tx_buff.len -= ret;
91 dev->raw_tx = 1;
92 ret = len; /* all data is going to be sent */
93 }
94 spin_unlock_irqrestore(&dev->tx_lock, flags);
95 return ret;
96 }
97
98 /* seems some dongle drivers may need this */
99
100 int sirdev_raw_read(struct sir_dev *dev, char *buf, int len)
101 {
102 int count;
103
104 if (atomic_read(&dev->enable_rx))
105 return -EIO; /* fail if we expect irda-frames */
106
107 count = (len < dev->rx_buff.len) ? len : dev->rx_buff.len;
108
109 if (count > 0) {
110 memcpy(buf, dev->rx_buff.data, count);
111 dev->rx_buff.data += count;
112 dev->rx_buff.len -= count;
113 }
114
115 /* remaining stuff gets flushed when re-enabling normal rx */
116
117 return count;
118 }
119
120 int sirdev_set_dtr_rts(struct sir_dev *dev, int dtr, int rts)
121 {
122 int ret = -ENXIO;
123 if (dev->drv->set_dtr_rts != 0)
124 ret = dev->drv->set_dtr_rts(dev, dtr, rts);
125 return ret;
126 }
127
128 /**********************************************************************/
129
130 /* called from client driver - likely with bh-context - to indicate
131 * it made some progress with transmission. Hence we send the next
132 * chunk, if any, or complete the skb otherwise
133 */
134
135 void sirdev_write_complete(struct sir_dev *dev)
136 {
137 unsigned long flags;
138 struct sk_buff *skb;
139 int actual = 0;
140 int err;
141
142 spin_lock_irqsave(&dev->tx_lock, flags);
143
144 IRDA_DEBUG(3, "%s() - dev->tx_buff.len = %d\n",
145 __FUNCTION__, dev->tx_buff.len);
146
147 if (likely(dev->tx_buff.len > 0)) {
148 /* Write data left in transmit buffer */
149 actual = dev->drv->do_write(dev, dev->tx_buff.data, dev->tx_buff.len);
150
151 if (likely(actual>0)) {
152 dev->tx_buff.data += actual;
153 dev->tx_buff.len -= actual;
154 }
155 else if (unlikely(actual<0)) {
156 /* could be dropped later when we have tx_timeout to recover */
157 IRDA_ERROR("%s: drv->do_write failed (%d)\n",
158 __FUNCTION__, actual);
159 if ((skb=dev->tx_skb) != NULL) {
160 dev->tx_skb = NULL;
161 dev_kfree_skb_any(skb);
162 dev->stats.tx_errors++;
163 dev->stats.tx_dropped++;
164 }
165 dev->tx_buff.len = 0;
166 }
167 if (dev->tx_buff.len > 0)
168 goto done; /* more data to send later */
169 }
170
171 if (unlikely(dev->raw_tx != 0)) {
172 /* in raw mode we are just done now after the buffer was sent
173 * completely. Since this was requested by some dongle driver
174 * running under the control of the irda-thread we must take
175 * care here not to re-enable the queue. The queue will be
176 * restarted when the irda-thread has completed the request.
177 */
178
179 IRDA_DEBUG(3, "%s(), raw-tx done\n", __FUNCTION__);
180 dev->raw_tx = 0;
181 goto done; /* no post-frame handling in raw mode */
182 }
183
184 /* we have finished now sending this skb.
185 * update statistics and free the skb.
186 * finally we check and trigger a pending speed change, if any.
187 * if not we switch to rx mode and wake the queue for further
188 * packets.
189 * note the scheduled speed request blocks until the lower
190 * client driver and the corresponding hardware has really
191 * finished sending all data (xmit fifo drained f.e.)
192 * before the speed change gets finally done and the queue
193 * re-activated.
194 */
195
196 IRDA_DEBUG(5, "%s(), finished with frame!\n", __FUNCTION__);
197
198 if ((skb=dev->tx_skb) != NULL) {
199 dev->tx_skb = NULL;
200 dev->stats.tx_packets++;
201 dev->stats.tx_bytes += skb->len;
202 dev_kfree_skb_any(skb);
203 }
204
205 if (unlikely(dev->new_speed > 0)) {
206 IRDA_DEBUG(5, "%s(), Changing speed!\n", __FUNCTION__);
207 err = sirdev_schedule_speed(dev, dev->new_speed);
208 if (unlikely(err)) {
209 /* should never happen
210 * forget the speed change and hope the stack recovers
211 */
212 IRDA_ERROR("%s - schedule speed change failed: %d\n",
213 __FUNCTION__, err);
214 netif_wake_queue(dev->netdev);
215 }
216 /* else: success
217 * speed change in progress now
218 * on completion dev->new_speed gets cleared,
219 * rx-reenabled and the queue restarted
220 */
221 }
222 else {
223 sirdev_enable_rx(dev);
224 netif_wake_queue(dev->netdev);
225 }
226
227 done:
228 spin_unlock_irqrestore(&dev->tx_lock, flags);
229 }
230
231 /* called from client driver - likely with bh-context - to give us
232 * some more received bytes. We put them into the rx-buffer,
233 * normally unwrapping and building LAP-skb's (unless rx disabled)
234 */
235
236 int sirdev_receive(struct sir_dev *dev, const unsigned char *cp, size_t count)
237 {
238 if (!dev || !dev->netdev) {
239 IRDA_WARNING("%s(), not ready yet!\n", __FUNCTION__);
240 return -1;
241 }
242
243 if (!dev->irlap) {
244 IRDA_WARNING("%s - too early: %p / %zd!\n",
245 __FUNCTION__, cp, count);
246 return -1;
247 }
248
249 if (cp==NULL) {
250 /* error already at lower level receive
251 * just update stats and set media busy
252 */
253 irda_device_set_media_busy(dev->netdev, TRUE);
254 dev->stats.rx_dropped++;
255 IRDA_DEBUG(0, "%s; rx-drop: %zd\n", __FUNCTION__, count);
256 return 0;
257 }
258
259 /* Read the characters into the buffer */
260 if (likely(atomic_read(&dev->enable_rx))) {
261 while (count--)
262 /* Unwrap and destuff one byte */
263 async_unwrap_char(dev->netdev, &dev->stats,
264 &dev->rx_buff, *cp++);
265 } else {
266 while (count--) {
267 /* rx not enabled: save the raw bytes and never
268 * trigger any netif_rx. The received bytes are flushed
269 * later when we re-enable rx but might be read meanwhile
270 * by the dongle driver.
271 */
272 dev->rx_buff.data[dev->rx_buff.len++] = *cp++;
273
274 /* What should we do when the buffer is full? */
275 if (unlikely(dev->rx_buff.len == dev->rx_buff.truesize))
276 dev->rx_buff.len = 0;
277 }
278 }
279
280 return 0;
281 }
282
283 /**********************************************************************/
284
285 /* callbacks from network layer */
286
287 static struct net_device_stats *sirdev_get_stats(struct net_device *ndev)
288 {
289 struct sir_dev *dev = ndev->priv;
290
291 return (dev) ? &dev->stats : NULL;
292 }
293
294 static int sirdev_hard_xmit(struct sk_buff *skb, struct net_device *ndev)
295 {
296 struct sir_dev *dev = ndev->priv;
297 unsigned long flags;
298 int actual = 0;
299 int err;
300 s32 speed;
301
302 IRDA_ASSERT(dev != NULL, return 0;);
303
304 netif_stop_queue(ndev);
305
306 IRDA_DEBUG(3, "%s(), skb->len = %d\n", __FUNCTION__, skb->len);
307
308 speed = irda_get_next_speed(skb);
309 if ((speed != dev->speed) && (speed != -1)) {
310 if (!skb->len) {
311 err = sirdev_schedule_speed(dev, speed);
312 if (unlikely(err == -EWOULDBLOCK)) {
313 /* Failed to initiate the speed change, likely the fsm
314 * is still busy (pretty unlikely, but...)
315 * We refuse to accept the skb and return with the queue
316 * stopped so the network layer will retry after the
317 * fsm completes and wakes the queue.
318 */
319 return 1;
320 }
321 else if (unlikely(err)) {
322 /* other fatal error - forget the speed change and
323 * hope the stack will recover somehow
324 */
325 netif_start_queue(ndev);
326 }
327 /* else: success
328 * speed change in progress now
329 * on completion the queue gets restarted
330 */
331
332 dev_kfree_skb_any(skb);
333 return 0;
334 } else
335 dev->new_speed = speed;
336 }
337
338 /* Init tx buffer*/
339 dev->tx_buff.data = dev->tx_buff.head;
340
341 /* Check problems */
342 if(spin_is_locked(&dev->tx_lock)) {
343 IRDA_DEBUG(3, "%s(), write not completed\n", __FUNCTION__);
344 }
345
346 /* serialize with write completion */
347 spin_lock_irqsave(&dev->tx_lock, flags);
348
349 /* Copy skb to tx_buff while wrapping, stuffing and making CRC */
350 dev->tx_buff.len = async_wrap_skb(skb, dev->tx_buff.data, dev->tx_buff.truesize);
351
352 /* transmission will start now - disable receive.
353 * if we are just in the middle of an incoming frame,
354 * treat it as collision. probably it's a good idea to
355 * reset the rx_buf OUTSIDE_FRAME in this case too?
356 */
357 atomic_set(&dev->enable_rx, 0);
358 if (unlikely(sirdev_is_receiving(dev)))
359 dev->stats.collisions++;
360
361 actual = dev->drv->do_write(dev, dev->tx_buff.data, dev->tx_buff.len);
362
363 if (likely(actual > 0)) {
364 dev->tx_skb = skb;
365 ndev->trans_start = jiffies;
366 dev->tx_buff.data += actual;
367 dev->tx_buff.len -= actual;
368 }
369 else if (unlikely(actual < 0)) {
370 /* could be dropped later when we have tx_timeout to recover */
371 IRDA_ERROR("%s: drv->do_write failed (%d)\n",
372 __FUNCTION__, actual);
373 dev_kfree_skb_any(skb);
374 dev->stats.tx_errors++;
375 dev->stats.tx_dropped++;
376 netif_wake_queue(ndev);
377 }
378 spin_unlock_irqrestore(&dev->tx_lock, flags);
379
380 return 0;
381 }
382
383 /* called from network layer with rtnl hold */
384
385 static int sirdev_ioctl(struct net_device *ndev, struct ifreq *rq, int cmd)
386 {
387 struct if_irda_req *irq = (struct if_irda_req *) rq;
388 struct sir_dev *dev = ndev->priv;
389 int ret = 0;
390
391 IRDA_ASSERT(dev != NULL, return -1;);
392
393 IRDA_DEBUG(3, "%s(), %s, (cmd=0x%X)\n", __FUNCTION__, ndev->name, cmd);
394
395 switch (cmd) {
396 case SIOCSBANDWIDTH: /* Set bandwidth */
397 if (!capable(CAP_NET_ADMIN))
398 ret = -EPERM;
399 else
400 ret = sirdev_schedule_speed(dev, irq->ifr_baudrate);
401 /* cannot sleep here for completion
402 * we are called from network layer with rtnl hold
403 */
404 break;
405
406 case SIOCSDONGLE: /* Set dongle */
407 if (!capable(CAP_NET_ADMIN))
408 ret = -EPERM;
409 else
410 ret = sirdev_schedule_dongle_open(dev, irq->ifr_dongle);
411 /* cannot sleep here for completion
412 * we are called from network layer with rtnl hold
413 */
414 break;
415
416 case SIOCSMEDIABUSY: /* Set media busy */
417 if (!capable(CAP_NET_ADMIN))
418 ret = -EPERM;
419 else
420 irda_device_set_media_busy(dev->netdev, TRUE);
421 break;
422
423 case SIOCGRECEIVING: /* Check if we are receiving right now */
424 irq->ifr_receiving = sirdev_is_receiving(dev);
425 break;
426
427 case SIOCSDTRRTS:
428 if (!capable(CAP_NET_ADMIN))
429 ret = -EPERM;
430 else
431 ret = sirdev_schedule_dtr_rts(dev, irq->ifr_dtr, irq->ifr_rts);
432 /* cannot sleep here for completion
433 * we are called from network layer with rtnl hold
434 */
435 break;
436
437 case SIOCSMODE:
438 #if 0
439 if (!capable(CAP_NET_ADMIN))
440 ret = -EPERM;
441 else
442 ret = sirdev_schedule_mode(dev, irq->ifr_mode);
443 /* cannot sleep here for completion
444 * we are called from network layer with rtnl hold
445 */
446 break;
447 #endif
448 default:
449 ret = -EOPNOTSUPP;
450 }
451
452 return ret;
453 }
454
455 /* ----------------------------------------------------------------------------- */
456
457 #define SIRBUF_ALLOCSIZE 4269 /* worst case size of a wrapped IrLAP frame */
458
459 static int sirdev_alloc_buffers(struct sir_dev *dev)
460 {
461 dev->tx_buff.truesize = SIRBUF_ALLOCSIZE;
462 dev->rx_buff.truesize = IRDA_SKB_MAX_MTU;
463
464 /* Bootstrap ZeroCopy Rx */
465 dev->rx_buff.skb = __dev_alloc_skb(dev->rx_buff.truesize, GFP_KERNEL);
466 if (dev->rx_buff.skb == NULL)
467 return -ENOMEM;
468 skb_reserve(dev->rx_buff.skb, 1);
469 dev->rx_buff.head = dev->rx_buff.skb->data;
470
471 dev->tx_buff.head = kmalloc(dev->tx_buff.truesize, GFP_KERNEL);
472 if (dev->tx_buff.head == NULL) {
473 kfree_skb(dev->rx_buff.skb);
474 dev->rx_buff.skb = NULL;
475 dev->rx_buff.head = NULL;
476 return -ENOMEM;
477 }
478
479 dev->tx_buff.data = dev->tx_buff.head;
480 dev->rx_buff.data = dev->rx_buff.head;
481 dev->tx_buff.len = 0;
482 dev->rx_buff.len = 0;
483
484 dev->rx_buff.in_frame = FALSE;
485 dev->rx_buff.state = OUTSIDE_FRAME;
486 return 0;
487 };
488
489 static void sirdev_free_buffers(struct sir_dev *dev)
490 {
491 if (dev->rx_buff.skb)
492 kfree_skb(dev->rx_buff.skb);
493 if (dev->tx_buff.head)
494 kfree(dev->tx_buff.head);
495 dev->rx_buff.head = dev->tx_buff.head = NULL;
496 dev->rx_buff.skb = NULL;
497 }
498
499 static int sirdev_open(struct net_device *ndev)
500 {
501 struct sir_dev *dev = ndev->priv;
502 const struct sir_driver *drv = dev->drv;
503
504 if (!drv)
505 return -ENODEV;
506
507 /* increase the reference count of the driver module before doing serious stuff */
508 if (!try_module_get(drv->owner))
509 return -ESTALE;
510
511 IRDA_DEBUG(2, "%s()\n", __FUNCTION__);
512
513 if (sirdev_alloc_buffers(dev))
514 goto errout_dec;
515
516 if (!dev->drv->start_dev || dev->drv->start_dev(dev))
517 goto errout_free;
518
519 sirdev_enable_rx(dev);
520 dev->raw_tx = 0;
521
522 netif_start_queue(ndev);
523 dev->irlap = irlap_open(ndev, &dev->qos, dev->hwname);
524 if (!dev->irlap)
525 goto errout_stop;
526
527 netif_wake_queue(ndev);
528
529 IRDA_DEBUG(2, "%s - done, speed = %d\n", __FUNCTION__, dev->speed);
530
531 return 0;
532
533 errout_stop:
534 atomic_set(&dev->enable_rx, 0);
535 if (dev->drv->stop_dev)
536 dev->drv->stop_dev(dev);
537 errout_free:
538 sirdev_free_buffers(dev);
539 errout_dec:
540 module_put(drv->owner);
541 return -EAGAIN;
542 }
543
544 static int sirdev_close(struct net_device *ndev)
545 {
546 struct sir_dev *dev = ndev->priv;
547 const struct sir_driver *drv;
548
549 // IRDA_DEBUG(0, "%s\n", __FUNCTION__);
550
551 netif_stop_queue(ndev);
552
553 down(&dev->fsm.sem); /* block on pending config completion */
554
555 atomic_set(&dev->enable_rx, 0);
556
557 if (unlikely(!dev->irlap))
558 goto out;
559 irlap_close(dev->irlap);
560 dev->irlap = NULL;
561
562 drv = dev->drv;
563 if (unlikely(!drv || !dev->priv))
564 goto out;
565
566 if (drv->stop_dev)
567 drv->stop_dev(dev);
568
569 sirdev_free_buffers(dev);
570 module_put(drv->owner);
571
572 out:
573 dev->speed = 0;
574 up(&dev->fsm.sem);
575 return 0;
576 }
577
578 /* ----------------------------------------------------------------------------- */
579
580 struct sir_dev * sirdev_get_instance(const struct sir_driver *drv, const char *name)
581 {
582 struct net_device *ndev;
583 struct sir_dev *dev;
584
585 IRDA_DEBUG(0, "%s - %s\n", __FUNCTION__, name);
586
587 /* instead of adding tests to protect against drv->do_write==NULL
588 * at several places we refuse to create a sir_dev instance for
589 * drivers which don't implement do_write.
590 */
591 if (!drv || !drv->do_write)
592 return NULL;
593
594 /*
595 * Allocate new instance of the device
596 */
597 ndev = alloc_irdadev(sizeof(*dev));
598 if (ndev == NULL) {
599 IRDA_ERROR("%s - Can't allocate memory for IrDA control block!\n", __FUNCTION__);
600 goto out;
601 }
602 dev = ndev->priv;
603
604 irda_init_max_qos_capabilies(&dev->qos);
605 dev->qos.baud_rate.bits = IR_9600|IR_19200|IR_38400|IR_57600|IR_115200;
606 dev->qos.min_turn_time.bits = drv->qos_mtt_bits;
607 irda_qos_bits_to_value(&dev->qos);
608
609 strncpy(dev->hwname, name, sizeof(dev->hwname)-1);
610
611 atomic_set(&dev->enable_rx, 0);
612 dev->tx_skb = NULL;
613
614 spin_lock_init(&dev->tx_lock);
615 init_MUTEX(&dev->fsm.sem);
616
617 INIT_LIST_HEAD(&dev->fsm.rq.lh_request);
618 dev->fsm.rq.pending = 0;
619 init_timer(&dev->fsm.rq.timer);
620
621 dev->drv = drv;
622 dev->netdev = ndev;
623
624 SET_MODULE_OWNER(ndev);
625
626 /* Override the network functions we need to use */
627 ndev->hard_start_xmit = sirdev_hard_xmit;
628 ndev->open = sirdev_open;
629 ndev->stop = sirdev_close;
630 ndev->get_stats = sirdev_get_stats;
631 ndev->do_ioctl = sirdev_ioctl;
632
633 if (register_netdev(ndev)) {
634 IRDA_ERROR("%s(), register_netdev() failed!\n", __FUNCTION__);
635 goto out_freenetdev;
636 }
637
638 return dev;
639
640 out_freenetdev:
641 free_netdev(ndev);
642 out:
643 return NULL;
644 }
645
646 int sirdev_put_instance(struct sir_dev *dev)
647 {
648 int err = 0;
649
650 IRDA_DEBUG(0, "%s\n", __FUNCTION__);
651
652 atomic_set(&dev->enable_rx, 0);
653
654 netif_carrier_off(dev->netdev);
655 netif_device_detach(dev->netdev);
656
657 if (dev->dongle_drv)
658 err = sirdev_schedule_dongle_close(dev);
659 if (err)
660 IRDA_ERROR("%s - error %d\n", __FUNCTION__, err);
661
662 sirdev_close(dev->netdev);
663
664 down(&dev->fsm.sem);
665 dev->fsm.state = SIRDEV_STATE_DEAD; /* mark staled */
666 dev->dongle_drv = NULL;
667 dev->priv = NULL;
668 up(&dev->fsm.sem);
669
670 /* Remove netdevice */
671 unregister_netdev(dev->netdev);
672
673 free_netdev(dev->netdev);
674
675 return 0;
676 }
677