1 /*
2 * CAN driver for PEAK System USB adapters
3 * Derived from the PCAN project file driver/src/pcan_usb_core.c
4 *
5 * Copyright (C) 2003-2010 PEAK System-Technik GmbH
6 * Copyright (C) 2010-2012 Stephane Grosjean <s.grosjean@peak-system.com>
7 *
8 * Many thanks to Klaus Hitschler <klaus.hitschler@gmx.de>
9 *
10 * This program is free software; you can redistribute it and/or modify it
11 * under the terms of the GNU General Public License as published
12 * by the Free Software Foundation; version 2 of the License.
13 *
14 * This program is distributed in the hope that it will be useful, but
15 * WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * General Public License for more details.
18 */
19 #include <linux/init.h>
20 #include <linux/signal.h>
21 #include <linux/slab.h>
22 #include <linux/module.h>
23 #include <linux/netdevice.h>
24 #include <linux/usb.h>
25
26 #include <linux/can.h>
27 #include <linux/can/dev.h>
28 #include <linux/can/error.h>
29
30 #include "pcan_usb_core.h"
31
32 MODULE_AUTHOR("Stephane Grosjean <s.grosjean@peak-system.com>");
33 MODULE_DESCRIPTION("CAN driver for PEAK-System USB adapters");
34 MODULE_LICENSE("GPL v2");
35
36 /* Table of devices that work with this driver */
37 static struct usb_device_id peak_usb_table[] = {
38 {USB_DEVICE(PCAN_USB_VENDOR_ID, PCAN_USB_PRODUCT_ID)},
39 {USB_DEVICE(PCAN_USB_VENDOR_ID, PCAN_USBPRO_PRODUCT_ID)},
40 {} /* Terminating entry */
41 };
42
43 MODULE_DEVICE_TABLE(usb, peak_usb_table);
44
45 /* List of supported PCAN-USB adapters (NULL terminated list) */
46 static struct peak_usb_adapter *peak_usb_adapters_list[] = {
47 &pcan_usb,
48 &pcan_usb_pro,
49 NULL,
50 };
51
52 /*
53 * dump memory
54 */
55 #define DUMP_WIDTH 16
pcan_dump_mem(char * prompt,void * p,int l)56 void pcan_dump_mem(char *prompt, void *p, int l)
57 {
58 pr_info("%s dumping %s (%d bytes):\n",
59 PCAN_USB_DRIVER_NAME, prompt ? prompt : "memory", l);
60 print_hex_dump(KERN_INFO, PCAN_USB_DRIVER_NAME " ", DUMP_PREFIX_NONE,
61 DUMP_WIDTH, 1, p, l, false);
62 }
63
64 /*
65 * initialize a time_ref object with usb adapter own settings
66 */
peak_usb_init_time_ref(struct peak_time_ref * time_ref,struct peak_usb_adapter * adapter)67 void peak_usb_init_time_ref(struct peak_time_ref *time_ref,
68 struct peak_usb_adapter *adapter)
69 {
70 if (time_ref) {
71 memset(time_ref, 0, sizeof(struct peak_time_ref));
72 time_ref->adapter = adapter;
73 }
74 }
75
peak_usb_add_us(struct timeval * tv,u32 delta_us)76 static void peak_usb_add_us(struct timeval *tv, u32 delta_us)
77 {
78 /* number of s. to add to final time */
79 u32 delta_s = delta_us / 1000000;
80
81 delta_us -= delta_s * 1000000;
82
83 tv->tv_usec += delta_us;
84 if (tv->tv_usec >= 1000000) {
85 tv->tv_usec -= 1000000;
86 delta_s++;
87 }
88 tv->tv_sec += delta_s;
89 }
90
91 /*
92 * sometimes, another now may be more recent than current one...
93 */
peak_usb_update_ts_now(struct peak_time_ref * time_ref,u32 ts_now)94 void peak_usb_update_ts_now(struct peak_time_ref *time_ref, u32 ts_now)
95 {
96 time_ref->ts_dev_2 = ts_now;
97
98 /* should wait at least two passes before computing */
99 if (time_ref->tv_host.tv_sec > 0) {
100 u32 delta_ts = time_ref->ts_dev_2 - time_ref->ts_dev_1;
101
102 if (time_ref->ts_dev_2 < time_ref->ts_dev_1)
103 delta_ts &= (1 << time_ref->adapter->ts_used_bits) - 1;
104
105 time_ref->ts_total += delta_ts;
106 }
107 }
108
109 /*
110 * register device timestamp as now
111 */
peak_usb_set_ts_now(struct peak_time_ref * time_ref,u32 ts_now)112 void peak_usb_set_ts_now(struct peak_time_ref *time_ref, u32 ts_now)
113 {
114 if (time_ref->tv_host_0.tv_sec == 0) {
115 /* use monotonic clock to correctly compute further deltas */
116 time_ref->tv_host_0 = ktime_to_timeval(ktime_get());
117 time_ref->tv_host.tv_sec = 0;
118 } else {
119 /*
120 * delta_us should not be >= 2^32 => delta_s should be < 4294
121 * handle 32-bits wrapping here: if count of s. reaches 4200,
122 * reset counters and change time base
123 */
124 if (time_ref->tv_host.tv_sec != 0) {
125 u32 delta_s = time_ref->tv_host.tv_sec
126 - time_ref->tv_host_0.tv_sec;
127 if (delta_s > 4200) {
128 time_ref->tv_host_0 = time_ref->tv_host;
129 time_ref->ts_total = 0;
130 }
131 }
132
133 time_ref->tv_host = ktime_to_timeval(ktime_get());
134 time_ref->tick_count++;
135 }
136
137 time_ref->ts_dev_1 = time_ref->ts_dev_2;
138 peak_usb_update_ts_now(time_ref, ts_now);
139 }
140
141 /*
142 * compute timeval according to current ts and time_ref data
143 */
peak_usb_get_ts_tv(struct peak_time_ref * time_ref,u32 ts,struct timeval * tv)144 void peak_usb_get_ts_tv(struct peak_time_ref *time_ref, u32 ts,
145 struct timeval *tv)
146 {
147 /* protect from getting timeval before setting now */
148 if (time_ref->tv_host.tv_sec > 0) {
149 u64 delta_us;
150
151 delta_us = ts - time_ref->ts_dev_2;
152 if (ts < time_ref->ts_dev_2)
153 delta_us &= (1 << time_ref->adapter->ts_used_bits) - 1;
154
155 delta_us += time_ref->ts_total;
156
157 delta_us *= time_ref->adapter->us_per_ts_scale;
158 delta_us >>= time_ref->adapter->us_per_ts_shift;
159
160 *tv = time_ref->tv_host_0;
161 peak_usb_add_us(tv, (u32)delta_us);
162 } else {
163 *tv = ktime_to_timeval(ktime_get());
164 }
165 }
166
167 /*
168 * callback for bulk Rx urb
169 */
peak_usb_read_bulk_callback(struct urb * urb)170 static void peak_usb_read_bulk_callback(struct urb *urb)
171 {
172 struct peak_usb_device *dev = urb->context;
173 struct net_device *netdev;
174 int err;
175
176 netdev = dev->netdev;
177
178 if (!netif_device_present(netdev))
179 return;
180
181 /* check reception status */
182 switch (urb->status) {
183 case 0:
184 /* success */
185 break;
186
187 case -EILSEQ:
188 case -ENOENT:
189 case -ECONNRESET:
190 case -ESHUTDOWN:
191 return;
192
193 default:
194 if (net_ratelimit())
195 netdev_err(netdev,
196 "Rx urb aborted (%d)\n", urb->status);
197 goto resubmit_urb;
198 }
199
200 /* protect from any incoming empty msgs */
201 if ((urb->actual_length > 0) && (dev->adapter->dev_decode_buf)) {
202 /* handle these kinds of msgs only if _start callback called */
203 if (dev->state & PCAN_USB_STATE_STARTED) {
204 err = dev->adapter->dev_decode_buf(dev, urb);
205 if (err)
206 pcan_dump_mem("received usb message",
207 urb->transfer_buffer,
208 urb->transfer_buffer_length);
209 }
210 }
211
212 resubmit_urb:
213 usb_fill_bulk_urb(urb, dev->udev,
214 usb_rcvbulkpipe(dev->udev, dev->ep_msg_in),
215 urb->transfer_buffer, dev->adapter->rx_buffer_size,
216 peak_usb_read_bulk_callback, dev);
217
218 usb_anchor_urb(urb, &dev->rx_submitted);
219 err = usb_submit_urb(urb, GFP_ATOMIC);
220 if (!err)
221 return;
222
223 usb_unanchor_urb(urb);
224
225 if (err == -ENODEV)
226 netif_device_detach(netdev);
227 else
228 netdev_err(netdev, "failed resubmitting read bulk urb: %d\n",
229 err);
230 }
231
232 /*
233 * callback for bulk Tx urb
234 */
peak_usb_write_bulk_callback(struct urb * urb)235 static void peak_usb_write_bulk_callback(struct urb *urb)
236 {
237 struct peak_tx_urb_context *context = urb->context;
238 struct peak_usb_device *dev;
239 struct net_device *netdev;
240
241 BUG_ON(!context);
242
243 dev = context->dev;
244 netdev = dev->netdev;
245
246 atomic_dec(&dev->active_tx_urbs);
247
248 if (!netif_device_present(netdev))
249 return;
250
251 /* check tx status */
252 switch (urb->status) {
253 case 0:
254 /* transmission complete */
255 netdev->stats.tx_packets++;
256 netdev->stats.tx_bytes += context->dlc;
257
258 /* prevent tx timeout */
259 netdev->trans_start = jiffies;
260 break;
261
262 default:
263 if (net_ratelimit())
264 netdev_err(netdev, "Tx urb aborted (%d)\n",
265 urb->status);
266 case -EPROTO:
267 case -ENOENT:
268 case -ECONNRESET:
269 case -ESHUTDOWN:
270
271 break;
272 }
273
274 /* should always release echo skb and corresponding context */
275 can_get_echo_skb(netdev, context->echo_index);
276 context->echo_index = PCAN_USB_MAX_TX_URBS;
277
278 /* do wakeup tx queue in case of success only */
279 if (!urb->status)
280 netif_wake_queue(netdev);
281 }
282
283 /*
284 * called by netdev to send one skb on the CAN interface.
285 */
peak_usb_ndo_start_xmit(struct sk_buff * skb,struct net_device * netdev)286 static netdev_tx_t peak_usb_ndo_start_xmit(struct sk_buff *skb,
287 struct net_device *netdev)
288 {
289 struct peak_usb_device *dev = netdev_priv(netdev);
290 struct peak_tx_urb_context *context = NULL;
291 struct net_device_stats *stats = &netdev->stats;
292 struct can_frame *cf = (struct can_frame *)skb->data;
293 struct urb *urb;
294 u8 *obuf;
295 int i, err;
296 size_t size = dev->adapter->tx_buffer_size;
297
298 if (can_dropped_invalid_skb(netdev, skb))
299 return NETDEV_TX_OK;
300
301 for (i = 0; i < PCAN_USB_MAX_TX_URBS; i++)
302 if (dev->tx_contexts[i].echo_index == PCAN_USB_MAX_TX_URBS) {
303 context = dev->tx_contexts + i;
304 break;
305 }
306
307 if (!context) {
308 /* should not occur except during restart */
309 return NETDEV_TX_BUSY;
310 }
311
312 urb = context->urb;
313 obuf = urb->transfer_buffer;
314
315 err = dev->adapter->dev_encode_msg(dev, skb, obuf, &size);
316 if (err) {
317 if (net_ratelimit())
318 netdev_err(netdev, "packet dropped\n");
319 dev_kfree_skb(skb);
320 stats->tx_dropped++;
321 return NETDEV_TX_OK;
322 }
323
324 context->echo_index = i;
325 context->dlc = cf->can_dlc;
326
327 usb_anchor_urb(urb, &dev->tx_submitted);
328
329 can_put_echo_skb(skb, netdev, context->echo_index);
330
331 atomic_inc(&dev->active_tx_urbs);
332
333 err = usb_submit_urb(urb, GFP_ATOMIC);
334 if (err) {
335 can_free_echo_skb(netdev, context->echo_index);
336
337 usb_unanchor_urb(urb);
338
339 /* this context is not used in fact */
340 context->echo_index = PCAN_USB_MAX_TX_URBS;
341
342 atomic_dec(&dev->active_tx_urbs);
343
344 switch (err) {
345 case -ENODEV:
346 netif_device_detach(netdev);
347 break;
348 default:
349 netdev_warn(netdev, "tx urb submitting failed err=%d\n",
350 err);
351 case -ENOENT:
352 /* cable unplugged */
353 stats->tx_dropped++;
354 }
355 } else {
356 netdev->trans_start = jiffies;
357
358 /* slow down tx path */
359 if (atomic_read(&dev->active_tx_urbs) >= PCAN_USB_MAX_TX_URBS)
360 netif_stop_queue(netdev);
361 }
362
363 return NETDEV_TX_OK;
364 }
365
366 /*
367 * start the CAN interface.
368 * Rx and Tx urbs are allocated here. Rx urbs are submitted here.
369 */
peak_usb_start(struct peak_usb_device * dev)370 static int peak_usb_start(struct peak_usb_device *dev)
371 {
372 struct net_device *netdev = dev->netdev;
373 int err, i;
374
375 for (i = 0; i < PCAN_USB_MAX_RX_URBS; i++) {
376 struct urb *urb;
377 u8 *buf;
378
379 /* create a URB, and a buffer for it, to receive usb messages */
380 urb = usb_alloc_urb(0, GFP_KERNEL);
381 if (!urb) {
382 netdev_err(netdev, "No memory left for URBs\n");
383 err = -ENOMEM;
384 break;
385 }
386
387 buf = kmalloc(dev->adapter->rx_buffer_size, GFP_KERNEL);
388 if (!buf) {
389 usb_free_urb(urb);
390 err = -ENOMEM;
391 break;
392 }
393
394 usb_fill_bulk_urb(urb, dev->udev,
395 usb_rcvbulkpipe(dev->udev, dev->ep_msg_in),
396 buf, dev->adapter->rx_buffer_size,
397 peak_usb_read_bulk_callback, dev);
398
399 /* ask last usb_free_urb() to also kfree() transfer_buffer */
400 urb->transfer_flags |= URB_FREE_BUFFER;
401 usb_anchor_urb(urb, &dev->rx_submitted);
402
403 err = usb_submit_urb(urb, GFP_KERNEL);
404 if (err) {
405 if (err == -ENODEV)
406 netif_device_detach(dev->netdev);
407
408 usb_unanchor_urb(urb);
409 kfree(buf);
410 usb_free_urb(urb);
411 break;
412 }
413
414 /* drop reference, USB core will take care of freeing it */
415 usb_free_urb(urb);
416 }
417
418 /* did we submit any URBs? Warn if we was not able to submit all urbs */
419 if (i < PCAN_USB_MAX_RX_URBS) {
420 if (i == 0) {
421 netdev_err(netdev, "couldn't setup any rx URB\n");
422 return err;
423 }
424
425 netdev_warn(netdev, "rx performance may be slow\n");
426 }
427
428 /* pre-alloc tx buffers and corresponding urbs */
429 for (i = 0; i < PCAN_USB_MAX_TX_URBS; i++) {
430 struct peak_tx_urb_context *context;
431 struct urb *urb;
432 u8 *buf;
433
434 /* create a URB and a buffer for it, to transmit usb messages */
435 urb = usb_alloc_urb(0, GFP_KERNEL);
436 if (!urb) {
437 netdev_err(netdev, "No memory left for URBs\n");
438 err = -ENOMEM;
439 break;
440 }
441
442 buf = kmalloc(dev->adapter->tx_buffer_size, GFP_KERNEL);
443 if (!buf) {
444 usb_free_urb(urb);
445 err = -ENOMEM;
446 break;
447 }
448
449 context = dev->tx_contexts + i;
450 context->dev = dev;
451 context->urb = urb;
452
453 usb_fill_bulk_urb(urb, dev->udev,
454 usb_sndbulkpipe(dev->udev, dev->ep_msg_out),
455 buf, dev->adapter->tx_buffer_size,
456 peak_usb_write_bulk_callback, context);
457
458 /* ask last usb_free_urb() to also kfree() transfer_buffer */
459 urb->transfer_flags |= URB_FREE_BUFFER;
460 }
461
462 /* warn if we were not able to allocate enough tx contexts */
463 if (i < PCAN_USB_MAX_TX_URBS) {
464 if (i == 0) {
465 netdev_err(netdev, "couldn't setup any tx URB\n");
466 goto err_tx;
467 }
468
469 netdev_warn(netdev, "tx performance may be slow\n");
470 }
471
472 if (dev->adapter->dev_start) {
473 err = dev->adapter->dev_start(dev);
474 if (err)
475 goto err_adapter;
476 }
477
478 dev->state |= PCAN_USB_STATE_STARTED;
479
480 /* can set bus on now */
481 if (dev->adapter->dev_set_bus) {
482 err = dev->adapter->dev_set_bus(dev, 1);
483 if (err)
484 goto err_adapter;
485 }
486
487 dev->can.state = CAN_STATE_ERROR_ACTIVE;
488
489 return 0;
490
491 err_adapter:
492 if (err == -ENODEV)
493 netif_device_detach(dev->netdev);
494
495 netdev_warn(netdev, "couldn't submit control: %d\n", err);
496
497 for (i = 0; i < PCAN_USB_MAX_TX_URBS; i++) {
498 usb_free_urb(dev->tx_contexts[i].urb);
499 dev->tx_contexts[i].urb = NULL;
500 }
501 err_tx:
502 usb_kill_anchored_urbs(&dev->rx_submitted);
503
504 return err;
505 }
506
507 /*
508 * called by netdev to open the corresponding CAN interface.
509 */
peak_usb_ndo_open(struct net_device * netdev)510 static int peak_usb_ndo_open(struct net_device *netdev)
511 {
512 struct peak_usb_device *dev = netdev_priv(netdev);
513 int err;
514
515 /* common open */
516 err = open_candev(netdev);
517 if (err)
518 return err;
519
520 /* finally start device */
521 err = peak_usb_start(dev);
522 if (err) {
523 netdev_err(netdev, "couldn't start device: %d\n", err);
524 close_candev(netdev);
525 return err;
526 }
527
528 netif_start_queue(netdev);
529
530 return 0;
531 }
532
533 /*
534 * unlink in-flight Rx and Tx urbs and free their memory.
535 */
peak_usb_unlink_all_urbs(struct peak_usb_device * dev)536 static void peak_usb_unlink_all_urbs(struct peak_usb_device *dev)
537 {
538 int i;
539
540 /* free all Rx (submitted) urbs */
541 usb_kill_anchored_urbs(&dev->rx_submitted);
542
543 /* free unsubmitted Tx urbs first */
544 for (i = 0; i < PCAN_USB_MAX_TX_URBS; i++) {
545 struct urb *urb = dev->tx_contexts[i].urb;
546
547 if (!urb ||
548 dev->tx_contexts[i].echo_index != PCAN_USB_MAX_TX_URBS) {
549 /*
550 * this urb is already released or always submitted,
551 * let usb core free by itself
552 */
553 continue;
554 }
555
556 usb_free_urb(urb);
557 dev->tx_contexts[i].urb = NULL;
558 }
559
560 /* then free all submitted Tx urbs */
561 usb_kill_anchored_urbs(&dev->tx_submitted);
562 atomic_set(&dev->active_tx_urbs, 0);
563 }
564
565 /*
566 * called by netdev to close the corresponding CAN interface.
567 */
peak_usb_ndo_stop(struct net_device * netdev)568 static int peak_usb_ndo_stop(struct net_device *netdev)
569 {
570 struct peak_usb_device *dev = netdev_priv(netdev);
571
572 dev->state &= ~PCAN_USB_STATE_STARTED;
573 netif_stop_queue(netdev);
574
575 /* unlink all pending urbs and free used memory */
576 peak_usb_unlink_all_urbs(dev);
577
578 if (dev->adapter->dev_stop)
579 dev->adapter->dev_stop(dev);
580
581 close_candev(netdev);
582
583 dev->can.state = CAN_STATE_STOPPED;
584
585 /* can set bus off now */
586 if (dev->adapter->dev_set_bus) {
587 int err = dev->adapter->dev_set_bus(dev, 0);
588 if (err)
589 return err;
590 }
591
592 return 0;
593 }
594
595 /*
596 * handle end of waiting for the device to reset
597 */
peak_usb_restart_complete(struct peak_usb_device * dev)598 void peak_usb_restart_complete(struct peak_usb_device *dev)
599 {
600 /* finally MUST update can state */
601 dev->can.state = CAN_STATE_ERROR_ACTIVE;
602
603 /* netdev queue can be awaken now */
604 netif_wake_queue(dev->netdev);
605 }
606
peak_usb_async_complete(struct urb * urb)607 void peak_usb_async_complete(struct urb *urb)
608 {
609 kfree(urb->transfer_buffer);
610 usb_free_urb(urb);
611 }
612
613 /*
614 * device (auto-)restart mechanism runs in a timer context =>
615 * MUST handle restart with asynchronous usb transfers
616 */
peak_usb_restart(struct peak_usb_device * dev)617 static int peak_usb_restart(struct peak_usb_device *dev)
618 {
619 struct urb *urb;
620 int err;
621 u8 *buf;
622
623 /*
624 * if device doesn't define any asynchronous restart handler, simply
625 * wake the netdev queue up
626 */
627 if (!dev->adapter->dev_restart_async) {
628 peak_usb_restart_complete(dev);
629 return 0;
630 }
631
632 /* first allocate a urb to handle the asynchronous steps */
633 urb = usb_alloc_urb(0, GFP_ATOMIC);
634 if (!urb) {
635 netdev_err(dev->netdev, "no memory left for urb\n");
636 return -ENOMEM;
637 }
638
639 /* also allocate enough space for the commands to send */
640 buf = kmalloc(PCAN_USB_MAX_CMD_LEN, GFP_ATOMIC);
641 if (!buf) {
642 usb_free_urb(urb);
643 return -ENOMEM;
644 }
645
646 /* call the device specific handler for the restart */
647 err = dev->adapter->dev_restart_async(dev, urb, buf);
648 if (!err)
649 return 0;
650
651 kfree(buf);
652 usb_free_urb(urb);
653
654 return err;
655 }
656
657 /*
658 * candev callback used to change CAN mode.
659 * Warning: this is called from a timer context!
660 */
peak_usb_set_mode(struct net_device * netdev,enum can_mode mode)661 static int peak_usb_set_mode(struct net_device *netdev, enum can_mode mode)
662 {
663 struct peak_usb_device *dev = netdev_priv(netdev);
664 int err = 0;
665
666 switch (mode) {
667 case CAN_MODE_START:
668 err = peak_usb_restart(dev);
669 if (err)
670 netdev_err(netdev, "couldn't start device (err %d)\n",
671 err);
672 break;
673
674 default:
675 return -EOPNOTSUPP;
676 }
677
678 return err;
679 }
680
681 /*
682 * candev callback used to set device bitrate.
683 */
peak_usb_set_bittiming(struct net_device * netdev)684 static int peak_usb_set_bittiming(struct net_device *netdev)
685 {
686 struct peak_usb_device *dev = netdev_priv(netdev);
687 struct can_bittiming *bt = &dev->can.bittiming;
688
689 if (dev->adapter->dev_set_bittiming) {
690 int err = dev->adapter->dev_set_bittiming(dev, bt);
691
692 if (err)
693 netdev_info(netdev, "couldn't set bitrate (err %d)\n",
694 err);
695 return err;
696 }
697
698 return 0;
699 }
700
701 static const struct net_device_ops peak_usb_netdev_ops = {
702 .ndo_open = peak_usb_ndo_open,
703 .ndo_stop = peak_usb_ndo_stop,
704 .ndo_start_xmit = peak_usb_ndo_start_xmit,
705 .ndo_change_mtu = can_change_mtu,
706 };
707
708 /*
709 * create one device which is attached to CAN controller #ctrl_idx of the
710 * usb adapter.
711 */
peak_usb_create_dev(struct peak_usb_adapter * peak_usb_adapter,struct usb_interface * intf,int ctrl_idx)712 static int peak_usb_create_dev(struct peak_usb_adapter *peak_usb_adapter,
713 struct usb_interface *intf, int ctrl_idx)
714 {
715 struct usb_device *usb_dev = interface_to_usbdev(intf);
716 int sizeof_candev = peak_usb_adapter->sizeof_dev_private;
717 struct peak_usb_device *dev;
718 struct net_device *netdev;
719 int i, err;
720 u16 tmp16;
721
722 if (sizeof_candev < sizeof(struct peak_usb_device))
723 sizeof_candev = sizeof(struct peak_usb_device);
724
725 netdev = alloc_candev(sizeof_candev, PCAN_USB_MAX_TX_URBS);
726 if (!netdev) {
727 dev_err(&intf->dev, "%s: couldn't alloc candev\n",
728 PCAN_USB_DRIVER_NAME);
729 return -ENOMEM;
730 }
731
732 dev = netdev_priv(netdev);
733
734 /* allocate a buffer large enough to send commands */
735 dev->cmd_buf = kmalloc(PCAN_USB_MAX_CMD_LEN, GFP_KERNEL);
736 if (!dev->cmd_buf) {
737 err = -ENOMEM;
738 goto lbl_free_candev;
739 }
740
741 dev->udev = usb_dev;
742 dev->netdev = netdev;
743 dev->adapter = peak_usb_adapter;
744 dev->ctrl_idx = ctrl_idx;
745 dev->state = PCAN_USB_STATE_CONNECTED;
746
747 dev->ep_msg_in = peak_usb_adapter->ep_msg_in;
748 dev->ep_msg_out = peak_usb_adapter->ep_msg_out[ctrl_idx];
749
750 dev->can.clock = peak_usb_adapter->clock;
751 dev->can.bittiming_const = &peak_usb_adapter->bittiming_const;
752 dev->can.do_set_bittiming = peak_usb_set_bittiming;
753 dev->can.do_set_mode = peak_usb_set_mode;
754 dev->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES |
755 CAN_CTRLMODE_LISTENONLY;
756
757 netdev->netdev_ops = &peak_usb_netdev_ops;
758
759 netdev->flags |= IFF_ECHO; /* we support local echo */
760
761 init_usb_anchor(&dev->rx_submitted);
762
763 init_usb_anchor(&dev->tx_submitted);
764 atomic_set(&dev->active_tx_urbs, 0);
765
766 for (i = 0; i < PCAN_USB_MAX_TX_URBS; i++)
767 dev->tx_contexts[i].echo_index = PCAN_USB_MAX_TX_URBS;
768
769 dev->prev_siblings = usb_get_intfdata(intf);
770 usb_set_intfdata(intf, dev);
771
772 SET_NETDEV_DEV(netdev, &intf->dev);
773 netdev->dev_id = ctrl_idx;
774
775 err = register_candev(netdev);
776 if (err) {
777 dev_err(&intf->dev, "couldn't register CAN device: %d\n", err);
778 goto lbl_restore_intf_data;
779 }
780
781 if (dev->prev_siblings)
782 (dev->prev_siblings)->next_siblings = dev;
783
784 /* keep hw revision into the netdevice */
785 tmp16 = le16_to_cpu(usb_dev->descriptor.bcdDevice);
786 dev->device_rev = tmp16 >> 8;
787
788 if (dev->adapter->dev_init) {
789 err = dev->adapter->dev_init(dev);
790 if (err)
791 goto lbl_unregister_candev;
792 }
793
794 /* set bus off */
795 if (dev->adapter->dev_set_bus) {
796 err = dev->adapter->dev_set_bus(dev, 0);
797 if (err)
798 goto lbl_unregister_candev;
799 }
800
801 /* get device number early */
802 if (dev->adapter->dev_get_device_id)
803 dev->adapter->dev_get_device_id(dev, &dev->device_number);
804
805 netdev_info(netdev, "attached to %s channel %u (device %u)\n",
806 peak_usb_adapter->name, ctrl_idx, dev->device_number);
807
808 return 0;
809
810 lbl_unregister_candev:
811 unregister_candev(netdev);
812
813 lbl_restore_intf_data:
814 usb_set_intfdata(intf, dev->prev_siblings);
815 kfree(dev->cmd_buf);
816
817 lbl_free_candev:
818 free_candev(netdev);
819
820 return err;
821 }
822
823 /*
824 * called by the usb core when the device is unplugged from the system
825 */
peak_usb_disconnect(struct usb_interface * intf)826 static void peak_usb_disconnect(struct usb_interface *intf)
827 {
828 struct peak_usb_device *dev;
829
830 /* unregister as many netdev devices as siblings */
831 for (dev = usb_get_intfdata(intf); dev; dev = dev->prev_siblings) {
832 struct net_device *netdev = dev->netdev;
833 char name[IFNAMSIZ];
834
835 dev->state &= ~PCAN_USB_STATE_CONNECTED;
836 strncpy(name, netdev->name, IFNAMSIZ);
837
838 unregister_netdev(netdev);
839 free_candev(netdev);
840
841 kfree(dev->cmd_buf);
842 dev->next_siblings = NULL;
843 if (dev->adapter->dev_free)
844 dev->adapter->dev_free(dev);
845
846 dev_info(&intf->dev, "%s removed\n", name);
847 }
848
849 usb_set_intfdata(intf, NULL);
850 }
851
852 /*
853 * probe function for new PEAK-System devices
854 */
peak_usb_probe(struct usb_interface * intf,const struct usb_device_id * id)855 static int peak_usb_probe(struct usb_interface *intf,
856 const struct usb_device_id *id)
857 {
858 struct usb_device *usb_dev = interface_to_usbdev(intf);
859 struct peak_usb_adapter *peak_usb_adapter, **pp;
860 int i, err = -ENOMEM;
861
862 usb_dev = interface_to_usbdev(intf);
863
864 /* get corresponding PCAN-USB adapter */
865 for (pp = peak_usb_adapters_list; *pp; pp++)
866 if ((*pp)->device_id == usb_dev->descriptor.idProduct)
867 break;
868
869 peak_usb_adapter = *pp;
870 if (!peak_usb_adapter) {
871 /* should never come except device_id bad usage in this file */
872 pr_err("%s: didn't find device id. 0x%x in devices list\n",
873 PCAN_USB_DRIVER_NAME, usb_dev->descriptor.idProduct);
874 return -ENODEV;
875 }
876
877 /* got corresponding adapter: check if it handles current interface */
878 if (peak_usb_adapter->intf_probe) {
879 err = peak_usb_adapter->intf_probe(intf);
880 if (err)
881 return err;
882 }
883
884 for (i = 0; i < peak_usb_adapter->ctrl_count; i++) {
885 err = peak_usb_create_dev(peak_usb_adapter, intf, i);
886 if (err) {
887 /* deregister already created devices */
888 peak_usb_disconnect(intf);
889 break;
890 }
891 }
892
893 return err;
894 }
895
896 /* usb specific object needed to register this driver with the usb subsystem */
897 static struct usb_driver peak_usb_driver = {
898 .name = PCAN_USB_DRIVER_NAME,
899 .disconnect = peak_usb_disconnect,
900 .probe = peak_usb_probe,
901 .id_table = peak_usb_table,
902 };
903
peak_usb_init(void)904 static int __init peak_usb_init(void)
905 {
906 int err;
907
908 /* register this driver with the USB subsystem */
909 err = usb_register(&peak_usb_driver);
910 if (err)
911 pr_err("%s: usb_register failed (err %d)\n",
912 PCAN_USB_DRIVER_NAME, err);
913
914 return err;
915 }
916
peak_usb_do_device_exit(struct device * d,void * arg)917 static int peak_usb_do_device_exit(struct device *d, void *arg)
918 {
919 struct usb_interface *intf = to_usb_interface(d);
920 struct peak_usb_device *dev;
921
922 /* stop as many netdev devices as siblings */
923 for (dev = usb_get_intfdata(intf); dev; dev = dev->prev_siblings) {
924 struct net_device *netdev = dev->netdev;
925
926 if (netif_device_present(netdev))
927 if (dev->adapter->dev_exit)
928 dev->adapter->dev_exit(dev);
929 }
930
931 return 0;
932 }
933
peak_usb_exit(void)934 static void __exit peak_usb_exit(void)
935 {
936 int err;
937
938 /* last chance do send any synchronous commands here */
939 err = driver_for_each_device(&peak_usb_driver.drvwrap.driver, NULL,
940 NULL, peak_usb_do_device_exit);
941 if (err)
942 pr_err("%s: failed to stop all can devices (err %d)\n",
943 PCAN_USB_DRIVER_NAME, err);
944
945 /* deregister this driver with the USB subsystem */
946 usb_deregister(&peak_usb_driver);
947
948 pr_info("%s: PCAN-USB interfaces driver unloaded\n",
949 PCAN_USB_DRIVER_NAME);
950 }
951
952 module_init(peak_usb_init);
953 module_exit(peak_usb_exit);
954