1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * CAN driver for PEAK System USB adapters
4 * Derived from the PCAN project file driver/src/pcan_usb_core.c
5 *
6 * Copyright (C) 2003-2010 PEAK System-Technik GmbH
7 * Copyright (C) 2010-2012 Stephane Grosjean <s.grosjean@peak-system.com>
8 *
9 * Many thanks to Klaus Hitschler <klaus.hitschler@gmx.de>
10 */
11 #include <linux/init.h>
12 #include <linux/signal.h>
13 #include <linux/slab.h>
14 #include <linux/module.h>
15 #include <linux/netdevice.h>
16 #include <linux/usb.h>
17
18 #include <linux/can.h>
19 #include <linux/can/dev.h>
20 #include <linux/can/error.h>
21
22 #include "pcan_usb_core.h"
23
24 MODULE_AUTHOR("Stephane Grosjean <s.grosjean@peak-system.com>");
25 MODULE_DESCRIPTION("CAN driver for PEAK-System USB adapters");
26 MODULE_LICENSE("GPL v2");
27
28 /* Table of devices that work with this driver */
29 static struct usb_device_id peak_usb_table[] = {
30 {USB_DEVICE(PCAN_USB_VENDOR_ID, PCAN_USB_PRODUCT_ID)},
31 {USB_DEVICE(PCAN_USB_VENDOR_ID, PCAN_USBPRO_PRODUCT_ID)},
32 {USB_DEVICE(PCAN_USB_VENDOR_ID, PCAN_USBFD_PRODUCT_ID)},
33 {USB_DEVICE(PCAN_USB_VENDOR_ID, PCAN_USBPROFD_PRODUCT_ID)},
34 {USB_DEVICE(PCAN_USB_VENDOR_ID, PCAN_USBCHIP_PRODUCT_ID)},
35 {USB_DEVICE(PCAN_USB_VENDOR_ID, PCAN_USBX6_PRODUCT_ID)},
36 {} /* Terminating entry */
37 };
38
39 MODULE_DEVICE_TABLE(usb, peak_usb_table);
40
41 /* List of supported PCAN-USB adapters (NULL terminated list) */
42 static const struct peak_usb_adapter *const peak_usb_adapters_list[] = {
43 &pcan_usb,
44 &pcan_usb_pro,
45 &pcan_usb_fd,
46 &pcan_usb_pro_fd,
47 &pcan_usb_chip,
48 &pcan_usb_x6,
49 };
50
51 /*
52 * dump memory
53 */
54 #define DUMP_WIDTH 16
pcan_dump_mem(char * prompt,void * p,int l)55 void pcan_dump_mem(char *prompt, void *p, int l)
56 {
57 pr_info("%s dumping %s (%d bytes):\n",
58 PCAN_USB_DRIVER_NAME, prompt ? prompt : "memory", l);
59 print_hex_dump(KERN_INFO, PCAN_USB_DRIVER_NAME " ", DUMP_PREFIX_NONE,
60 DUMP_WIDTH, 1, p, l, false);
61 }
62
63 /*
64 * initialize a time_ref object with usb adapter own settings
65 */
peak_usb_init_time_ref(struct peak_time_ref * time_ref,const struct peak_usb_adapter * adapter)66 void peak_usb_init_time_ref(struct peak_time_ref *time_ref,
67 const struct peak_usb_adapter *adapter)
68 {
69 if (time_ref) {
70 memset(time_ref, 0, sizeof(struct peak_time_ref));
71 time_ref->adapter = adapter;
72 }
73 }
74
75 /*
76 * sometimes, another now may be more recent than current one...
77 */
peak_usb_update_ts_now(struct peak_time_ref * time_ref,u32 ts_now)78 void peak_usb_update_ts_now(struct peak_time_ref *time_ref, u32 ts_now)
79 {
80 time_ref->ts_dev_2 = ts_now;
81
82 /* should wait at least two passes before computing */
83 if (ktime_to_ns(time_ref->tv_host) > 0) {
84 u32 delta_ts = time_ref->ts_dev_2 - time_ref->ts_dev_1;
85
86 if (time_ref->ts_dev_2 < time_ref->ts_dev_1)
87 delta_ts &= (1 << time_ref->adapter->ts_used_bits) - 1;
88
89 time_ref->ts_total += delta_ts;
90 }
91 }
92
93 /*
94 * register device timestamp as now
95 */
peak_usb_set_ts_now(struct peak_time_ref * time_ref,u32 ts_now)96 void peak_usb_set_ts_now(struct peak_time_ref *time_ref, u32 ts_now)
97 {
98 if (ktime_to_ns(time_ref->tv_host_0) == 0) {
99 /* use monotonic clock to correctly compute further deltas */
100 time_ref->tv_host_0 = ktime_get();
101 time_ref->tv_host = ktime_set(0, 0);
102 } else {
103 /*
104 * delta_us should not be >= 2^32 => delta should be < 4294s
105 * handle 32-bits wrapping here: if count of s. reaches 4200,
106 * reset counters and change time base
107 */
108 if (ktime_to_ns(time_ref->tv_host)) {
109 ktime_t delta = ktime_sub(time_ref->tv_host,
110 time_ref->tv_host_0);
111 if (ktime_to_ns(delta) > (4200ull * NSEC_PER_SEC)) {
112 time_ref->tv_host_0 = time_ref->tv_host;
113 time_ref->ts_total = 0;
114 }
115 }
116
117 time_ref->tv_host = ktime_get();
118 time_ref->tick_count++;
119 }
120
121 time_ref->ts_dev_1 = time_ref->ts_dev_2;
122 peak_usb_update_ts_now(time_ref, ts_now);
123 }
124
125 /*
126 * compute time according to current ts and time_ref data
127 */
peak_usb_get_ts_time(struct peak_time_ref * time_ref,u32 ts,ktime_t * time)128 void peak_usb_get_ts_time(struct peak_time_ref *time_ref, u32 ts, ktime_t *time)
129 {
130 /* protect from getting time before setting now */
131 if (ktime_to_ns(time_ref->tv_host)) {
132 u64 delta_us;
133
134 delta_us = ts - time_ref->ts_dev_2;
135 if (ts < time_ref->ts_dev_2)
136 delta_us &= (1 << time_ref->adapter->ts_used_bits) - 1;
137
138 delta_us += time_ref->ts_total;
139
140 delta_us *= time_ref->adapter->us_per_ts_scale;
141 delta_us >>= time_ref->adapter->us_per_ts_shift;
142
143 *time = ktime_add_us(time_ref->tv_host_0, delta_us);
144 } else {
145 *time = ktime_get();
146 }
147 }
148
149 /*
150 * post received skb after having set any hw timestamp
151 */
peak_usb_netif_rx(struct sk_buff * skb,struct peak_time_ref * time_ref,u32 ts_low)152 int peak_usb_netif_rx(struct sk_buff *skb,
153 struct peak_time_ref *time_ref, u32 ts_low)
154 {
155 struct skb_shared_hwtstamps *hwts = skb_hwtstamps(skb);
156
157 peak_usb_get_ts_time(time_ref, ts_low, &hwts->hwtstamp);
158
159 return netif_rx(skb);
160 }
161
162 /*
163 * callback for bulk Rx urb
164 */
peak_usb_read_bulk_callback(struct urb * urb)165 static void peak_usb_read_bulk_callback(struct urb *urb)
166 {
167 struct peak_usb_device *dev = urb->context;
168 struct net_device *netdev;
169 int err;
170
171 netdev = dev->netdev;
172
173 if (!netif_device_present(netdev))
174 return;
175
176 /* check reception status */
177 switch (urb->status) {
178 case 0:
179 /* success */
180 break;
181
182 case -EILSEQ:
183 case -ENOENT:
184 case -ECONNRESET:
185 case -ESHUTDOWN:
186 return;
187
188 default:
189 if (net_ratelimit())
190 netdev_err(netdev,
191 "Rx urb aborted (%d)\n", urb->status);
192 goto resubmit_urb;
193 }
194
195 /* protect from any incoming empty msgs */
196 if ((urb->actual_length > 0) && (dev->adapter->dev_decode_buf)) {
197 /* handle these kinds of msgs only if _start callback called */
198 if (dev->state & PCAN_USB_STATE_STARTED) {
199 err = dev->adapter->dev_decode_buf(dev, urb);
200 if (err)
201 pcan_dump_mem("received usb message",
202 urb->transfer_buffer,
203 urb->transfer_buffer_length);
204 }
205 }
206
207 resubmit_urb:
208 usb_fill_bulk_urb(urb, dev->udev,
209 usb_rcvbulkpipe(dev->udev, dev->ep_msg_in),
210 urb->transfer_buffer, dev->adapter->rx_buffer_size,
211 peak_usb_read_bulk_callback, dev);
212
213 usb_anchor_urb(urb, &dev->rx_submitted);
214 err = usb_submit_urb(urb, GFP_ATOMIC);
215 if (!err)
216 return;
217
218 usb_unanchor_urb(urb);
219
220 if (err == -ENODEV)
221 netif_device_detach(netdev);
222 else
223 netdev_err(netdev, "failed resubmitting read bulk urb: %d\n",
224 err);
225 }
226
227 /*
228 * callback for bulk Tx urb
229 */
peak_usb_write_bulk_callback(struct urb * urb)230 static void peak_usb_write_bulk_callback(struct urb *urb)
231 {
232 struct peak_tx_urb_context *context = urb->context;
233 struct peak_usb_device *dev;
234 struct net_device *netdev;
235
236 BUG_ON(!context);
237
238 dev = context->dev;
239 netdev = dev->netdev;
240
241 atomic_dec(&dev->active_tx_urbs);
242
243 if (!netif_device_present(netdev))
244 return;
245
246 /* check tx status */
247 switch (urb->status) {
248 case 0:
249 /* transmission complete */
250 netdev->stats.tx_packets++;
251 netdev->stats.tx_bytes += context->data_len;
252
253 /* prevent tx timeout */
254 netif_trans_update(netdev);
255 break;
256
257 default:
258 if (net_ratelimit())
259 netdev_err(netdev, "Tx urb aborted (%d)\n",
260 urb->status);
261 case -EPROTO:
262 case -ENOENT:
263 case -ECONNRESET:
264 case -ESHUTDOWN:
265
266 break;
267 }
268
269 /* should always release echo skb and corresponding context */
270 can_get_echo_skb(netdev, context->echo_index);
271 context->echo_index = PCAN_USB_MAX_TX_URBS;
272
273 /* do wakeup tx queue in case of success only */
274 if (!urb->status)
275 netif_wake_queue(netdev);
276 }
277
278 /*
279 * called by netdev to send one skb on the CAN interface.
280 */
peak_usb_ndo_start_xmit(struct sk_buff * skb,struct net_device * netdev)281 static netdev_tx_t peak_usb_ndo_start_xmit(struct sk_buff *skb,
282 struct net_device *netdev)
283 {
284 struct peak_usb_device *dev = netdev_priv(netdev);
285 struct peak_tx_urb_context *context = NULL;
286 struct net_device_stats *stats = &netdev->stats;
287 struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
288 struct urb *urb;
289 u8 *obuf;
290 int i, err;
291 size_t size = dev->adapter->tx_buffer_size;
292
293 if (can_dropped_invalid_skb(netdev, skb))
294 return NETDEV_TX_OK;
295
296 for (i = 0; i < PCAN_USB_MAX_TX_URBS; i++)
297 if (dev->tx_contexts[i].echo_index == PCAN_USB_MAX_TX_URBS) {
298 context = dev->tx_contexts + i;
299 break;
300 }
301
302 if (!context) {
303 /* should not occur except during restart */
304 return NETDEV_TX_BUSY;
305 }
306
307 urb = context->urb;
308 obuf = urb->transfer_buffer;
309
310 err = dev->adapter->dev_encode_msg(dev, skb, obuf, &size);
311 if (err) {
312 if (net_ratelimit())
313 netdev_err(netdev, "packet dropped\n");
314 dev_kfree_skb(skb);
315 stats->tx_dropped++;
316 return NETDEV_TX_OK;
317 }
318
319 context->echo_index = i;
320
321 /* Note: this works with CANFD frames too */
322 context->data_len = cfd->len;
323
324 usb_anchor_urb(urb, &dev->tx_submitted);
325
326 can_put_echo_skb(skb, netdev, context->echo_index);
327
328 atomic_inc(&dev->active_tx_urbs);
329
330 err = usb_submit_urb(urb, GFP_ATOMIC);
331 if (err) {
332 can_free_echo_skb(netdev, context->echo_index);
333
334 usb_unanchor_urb(urb);
335
336 /* this context is not used in fact */
337 context->echo_index = PCAN_USB_MAX_TX_URBS;
338
339 atomic_dec(&dev->active_tx_urbs);
340
341 switch (err) {
342 case -ENODEV:
343 netif_device_detach(netdev);
344 break;
345 default:
346 netdev_warn(netdev, "tx urb submitting failed err=%d\n",
347 err);
348 /* fall through */
349 case -ENOENT:
350 /* cable unplugged */
351 stats->tx_dropped++;
352 }
353 } else {
354 netif_trans_update(netdev);
355
356 /* slow down tx path */
357 if (atomic_read(&dev->active_tx_urbs) >= PCAN_USB_MAX_TX_URBS)
358 netif_stop_queue(netdev);
359 }
360
361 return NETDEV_TX_OK;
362 }
363
364 /*
365 * start the CAN interface.
366 * Rx and Tx urbs are allocated here. Rx urbs are submitted here.
367 */
peak_usb_start(struct peak_usb_device * dev)368 static int peak_usb_start(struct peak_usb_device *dev)
369 {
370 struct net_device *netdev = dev->netdev;
371 int err, i;
372
373 for (i = 0; i < PCAN_USB_MAX_RX_URBS; i++) {
374 struct urb *urb;
375 u8 *buf;
376
377 /* create a URB, and a buffer for it, to receive usb messages */
378 urb = usb_alloc_urb(0, GFP_KERNEL);
379 if (!urb) {
380 err = -ENOMEM;
381 break;
382 }
383
384 buf = kmalloc(dev->adapter->rx_buffer_size, GFP_KERNEL);
385 if (!buf) {
386 usb_free_urb(urb);
387 err = -ENOMEM;
388 break;
389 }
390
391 usb_fill_bulk_urb(urb, dev->udev,
392 usb_rcvbulkpipe(dev->udev, dev->ep_msg_in),
393 buf, dev->adapter->rx_buffer_size,
394 peak_usb_read_bulk_callback, dev);
395
396 /* ask last usb_free_urb() to also kfree() transfer_buffer */
397 urb->transfer_flags |= URB_FREE_BUFFER;
398 usb_anchor_urb(urb, &dev->rx_submitted);
399
400 err = usb_submit_urb(urb, GFP_KERNEL);
401 if (err) {
402 if (err == -ENODEV)
403 netif_device_detach(dev->netdev);
404
405 usb_unanchor_urb(urb);
406 kfree(buf);
407 usb_free_urb(urb);
408 break;
409 }
410
411 /* drop reference, USB core will take care of freeing it */
412 usb_free_urb(urb);
413 }
414
415 /* did we submit any URBs? Warn if we was not able to submit all urbs */
416 if (i < PCAN_USB_MAX_RX_URBS) {
417 if (i == 0) {
418 netdev_err(netdev, "couldn't setup any rx URB\n");
419 return err;
420 }
421
422 netdev_warn(netdev, "rx performance may be slow\n");
423 }
424
425 /* pre-alloc tx buffers and corresponding urbs */
426 for (i = 0; i < PCAN_USB_MAX_TX_URBS; i++) {
427 struct peak_tx_urb_context *context;
428 struct urb *urb;
429 u8 *buf;
430
431 /* create a URB and a buffer for it, to transmit usb messages */
432 urb = usb_alloc_urb(0, GFP_KERNEL);
433 if (!urb) {
434 err = -ENOMEM;
435 break;
436 }
437
438 buf = kmalloc(dev->adapter->tx_buffer_size, GFP_KERNEL);
439 if (!buf) {
440 usb_free_urb(urb);
441 err = -ENOMEM;
442 break;
443 }
444
445 context = dev->tx_contexts + i;
446 context->dev = dev;
447 context->urb = urb;
448
449 usb_fill_bulk_urb(urb, dev->udev,
450 usb_sndbulkpipe(dev->udev, dev->ep_msg_out),
451 buf, dev->adapter->tx_buffer_size,
452 peak_usb_write_bulk_callback, context);
453
454 /* ask last usb_free_urb() to also kfree() transfer_buffer */
455 urb->transfer_flags |= URB_FREE_BUFFER;
456 }
457
458 /* warn if we were not able to allocate enough tx contexts */
459 if (i < PCAN_USB_MAX_TX_URBS) {
460 if (i == 0) {
461 netdev_err(netdev, "couldn't setup any tx URB\n");
462 goto err_tx;
463 }
464
465 netdev_warn(netdev, "tx performance may be slow\n");
466 }
467
468 if (dev->adapter->dev_start) {
469 err = dev->adapter->dev_start(dev);
470 if (err)
471 goto err_adapter;
472 }
473
474 dev->state |= PCAN_USB_STATE_STARTED;
475
476 /* can set bus on now */
477 if (dev->adapter->dev_set_bus) {
478 err = dev->adapter->dev_set_bus(dev, 1);
479 if (err)
480 goto err_adapter;
481 }
482
483 dev->can.state = CAN_STATE_ERROR_ACTIVE;
484
485 return 0;
486
487 err_adapter:
488 if (err == -ENODEV)
489 netif_device_detach(dev->netdev);
490
491 netdev_warn(netdev, "couldn't submit control: %d\n", err);
492
493 for (i = 0; i < PCAN_USB_MAX_TX_URBS; i++) {
494 usb_free_urb(dev->tx_contexts[i].urb);
495 dev->tx_contexts[i].urb = NULL;
496 }
497 err_tx:
498 usb_kill_anchored_urbs(&dev->rx_submitted);
499
500 return err;
501 }
502
503 /*
504 * called by netdev to open the corresponding CAN interface.
505 */
peak_usb_ndo_open(struct net_device * netdev)506 static int peak_usb_ndo_open(struct net_device *netdev)
507 {
508 struct peak_usb_device *dev = netdev_priv(netdev);
509 int err;
510
511 /* common open */
512 err = open_candev(netdev);
513 if (err)
514 return err;
515
516 /* finally start device */
517 err = peak_usb_start(dev);
518 if (err) {
519 netdev_err(netdev, "couldn't start device: %d\n", err);
520 close_candev(netdev);
521 return err;
522 }
523
524 netif_start_queue(netdev);
525
526 return 0;
527 }
528
529 /*
530 * unlink in-flight Rx and Tx urbs and free their memory.
531 */
peak_usb_unlink_all_urbs(struct peak_usb_device * dev)532 static void peak_usb_unlink_all_urbs(struct peak_usb_device *dev)
533 {
534 int i;
535
536 /* free all Rx (submitted) urbs */
537 usb_kill_anchored_urbs(&dev->rx_submitted);
538
539 /* free unsubmitted Tx urbs first */
540 for (i = 0; i < PCAN_USB_MAX_TX_URBS; i++) {
541 struct urb *urb = dev->tx_contexts[i].urb;
542
543 if (!urb ||
544 dev->tx_contexts[i].echo_index != PCAN_USB_MAX_TX_URBS) {
545 /*
546 * this urb is already released or always submitted,
547 * let usb core free by itself
548 */
549 continue;
550 }
551
552 usb_free_urb(urb);
553 dev->tx_contexts[i].urb = NULL;
554 }
555
556 /* then free all submitted Tx urbs */
557 usb_kill_anchored_urbs(&dev->tx_submitted);
558 atomic_set(&dev->active_tx_urbs, 0);
559 }
560
561 /*
562 * called by netdev to close the corresponding CAN interface.
563 */
peak_usb_ndo_stop(struct net_device * netdev)564 static int peak_usb_ndo_stop(struct net_device *netdev)
565 {
566 struct peak_usb_device *dev = netdev_priv(netdev);
567
568 dev->state &= ~PCAN_USB_STATE_STARTED;
569 netif_stop_queue(netdev);
570
571 close_candev(netdev);
572
573 dev->can.state = CAN_STATE_STOPPED;
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 /* can set bus off now */
582 if (dev->adapter->dev_set_bus) {
583 int err = dev->adapter->dev_set_bus(dev, 0);
584 if (err)
585 return err;
586 }
587
588 return 0;
589 }
590
591 /*
592 * handle end of waiting for the device to reset
593 */
peak_usb_restart_complete(struct peak_usb_device * dev)594 void peak_usb_restart_complete(struct peak_usb_device *dev)
595 {
596 /* finally MUST update can state */
597 dev->can.state = CAN_STATE_ERROR_ACTIVE;
598
599 /* netdev queue can be awaken now */
600 netif_wake_queue(dev->netdev);
601 }
602
peak_usb_async_complete(struct urb * urb)603 void peak_usb_async_complete(struct urb *urb)
604 {
605 kfree(urb->transfer_buffer);
606 usb_free_urb(urb);
607 }
608
609 /*
610 * device (auto-)restart mechanism runs in a timer context =>
611 * MUST handle restart with asynchronous usb transfers
612 */
peak_usb_restart(struct peak_usb_device * dev)613 static int peak_usb_restart(struct peak_usb_device *dev)
614 {
615 struct urb *urb;
616 int err;
617 u8 *buf;
618
619 /*
620 * if device doesn't define any asynchronous restart handler, simply
621 * wake the netdev queue up
622 */
623 if (!dev->adapter->dev_restart_async) {
624 peak_usb_restart_complete(dev);
625 return 0;
626 }
627
628 /* first allocate a urb to handle the asynchronous steps */
629 urb = usb_alloc_urb(0, GFP_ATOMIC);
630 if (!urb)
631 return -ENOMEM;
632
633 /* also allocate enough space for the commands to send */
634 buf = kmalloc(PCAN_USB_MAX_CMD_LEN, GFP_ATOMIC);
635 if (!buf) {
636 usb_free_urb(urb);
637 return -ENOMEM;
638 }
639
640 /* call the device specific handler for the restart */
641 err = dev->adapter->dev_restart_async(dev, urb, buf);
642 if (!err)
643 return 0;
644
645 kfree(buf);
646 usb_free_urb(urb);
647
648 return err;
649 }
650
651 /*
652 * candev callback used to change CAN mode.
653 * Warning: this is called from a timer context!
654 */
peak_usb_set_mode(struct net_device * netdev,enum can_mode mode)655 static int peak_usb_set_mode(struct net_device *netdev, enum can_mode mode)
656 {
657 struct peak_usb_device *dev = netdev_priv(netdev);
658 int err = 0;
659
660 switch (mode) {
661 case CAN_MODE_START:
662 err = peak_usb_restart(dev);
663 if (err)
664 netdev_err(netdev, "couldn't start device (err %d)\n",
665 err);
666 break;
667
668 default:
669 return -EOPNOTSUPP;
670 }
671
672 return err;
673 }
674
675 /*
676 * candev callback used to set device nominal/arbitration bitrate.
677 */
peak_usb_set_bittiming(struct net_device * netdev)678 static int peak_usb_set_bittiming(struct net_device *netdev)
679 {
680 struct peak_usb_device *dev = netdev_priv(netdev);
681 const struct peak_usb_adapter *pa = dev->adapter;
682
683 if (pa->dev_set_bittiming) {
684 struct can_bittiming *bt = &dev->can.bittiming;
685 int err = pa->dev_set_bittiming(dev, bt);
686
687 if (err)
688 netdev_info(netdev, "couldn't set bitrate (err %d)\n",
689 err);
690 return err;
691 }
692
693 return 0;
694 }
695
696 /*
697 * candev callback used to set device data bitrate.
698 */
peak_usb_set_data_bittiming(struct net_device * netdev)699 static int peak_usb_set_data_bittiming(struct net_device *netdev)
700 {
701 struct peak_usb_device *dev = netdev_priv(netdev);
702 const struct peak_usb_adapter *pa = dev->adapter;
703
704 if (pa->dev_set_data_bittiming) {
705 struct can_bittiming *bt = &dev->can.data_bittiming;
706 int err = pa->dev_set_data_bittiming(dev, bt);
707
708 if (err)
709 netdev_info(netdev,
710 "couldn't set data bitrate (err %d)\n",
711 err);
712
713 return err;
714 }
715
716 return 0;
717 }
718
719 static const struct net_device_ops peak_usb_netdev_ops = {
720 .ndo_open = peak_usb_ndo_open,
721 .ndo_stop = peak_usb_ndo_stop,
722 .ndo_start_xmit = peak_usb_ndo_start_xmit,
723 .ndo_change_mtu = can_change_mtu,
724 };
725
726 /*
727 * create one device which is attached to CAN controller #ctrl_idx of the
728 * usb adapter.
729 */
peak_usb_create_dev(const struct peak_usb_adapter * peak_usb_adapter,struct usb_interface * intf,int ctrl_idx)730 static int peak_usb_create_dev(const struct peak_usb_adapter *peak_usb_adapter,
731 struct usb_interface *intf, int ctrl_idx)
732 {
733 struct usb_device *usb_dev = interface_to_usbdev(intf);
734 int sizeof_candev = peak_usb_adapter->sizeof_dev_private;
735 struct peak_usb_device *dev;
736 struct net_device *netdev;
737 int i, err;
738 u16 tmp16;
739
740 if (sizeof_candev < sizeof(struct peak_usb_device))
741 sizeof_candev = sizeof(struct peak_usb_device);
742
743 netdev = alloc_candev(sizeof_candev, PCAN_USB_MAX_TX_URBS);
744 if (!netdev) {
745 dev_err(&intf->dev, "%s: couldn't alloc candev\n",
746 PCAN_USB_DRIVER_NAME);
747 return -ENOMEM;
748 }
749
750 dev = netdev_priv(netdev);
751
752 /* allocate a buffer large enough to send commands */
753 dev->cmd_buf = kzalloc(PCAN_USB_MAX_CMD_LEN, GFP_KERNEL);
754 if (!dev->cmd_buf) {
755 err = -ENOMEM;
756 goto lbl_free_candev;
757 }
758
759 dev->udev = usb_dev;
760 dev->netdev = netdev;
761 dev->adapter = peak_usb_adapter;
762 dev->ctrl_idx = ctrl_idx;
763 dev->state = PCAN_USB_STATE_CONNECTED;
764
765 dev->ep_msg_in = peak_usb_adapter->ep_msg_in;
766 dev->ep_msg_out = peak_usb_adapter->ep_msg_out[ctrl_idx];
767
768 dev->can.clock = peak_usb_adapter->clock;
769 dev->can.bittiming_const = peak_usb_adapter->bittiming_const;
770 dev->can.do_set_bittiming = peak_usb_set_bittiming;
771 dev->can.data_bittiming_const = peak_usb_adapter->data_bittiming_const;
772 dev->can.do_set_data_bittiming = peak_usb_set_data_bittiming;
773 dev->can.do_set_mode = peak_usb_set_mode;
774 dev->can.do_get_berr_counter = peak_usb_adapter->do_get_berr_counter;
775 dev->can.ctrlmode_supported = peak_usb_adapter->ctrlmode_supported;
776
777 netdev->netdev_ops = &peak_usb_netdev_ops;
778
779 netdev->flags |= IFF_ECHO; /* we support local echo */
780
781 init_usb_anchor(&dev->rx_submitted);
782
783 init_usb_anchor(&dev->tx_submitted);
784 atomic_set(&dev->active_tx_urbs, 0);
785
786 for (i = 0; i < PCAN_USB_MAX_TX_URBS; i++)
787 dev->tx_contexts[i].echo_index = PCAN_USB_MAX_TX_URBS;
788
789 dev->prev_siblings = usb_get_intfdata(intf);
790 usb_set_intfdata(intf, dev);
791
792 SET_NETDEV_DEV(netdev, &intf->dev);
793 netdev->dev_id = ctrl_idx;
794
795 err = register_candev(netdev);
796 if (err) {
797 dev_err(&intf->dev, "couldn't register CAN device: %d\n", err);
798 goto lbl_restore_intf_data;
799 }
800
801 if (dev->prev_siblings)
802 (dev->prev_siblings)->next_siblings = dev;
803
804 /* keep hw revision into the netdevice */
805 tmp16 = le16_to_cpu(usb_dev->descriptor.bcdDevice);
806 dev->device_rev = tmp16 >> 8;
807
808 if (dev->adapter->dev_init) {
809 err = dev->adapter->dev_init(dev);
810 if (err)
811 goto lbl_unregister_candev;
812 }
813
814 /* set bus off */
815 if (dev->adapter->dev_set_bus) {
816 err = dev->adapter->dev_set_bus(dev, 0);
817 if (err)
818 goto lbl_unregister_candev;
819 }
820
821 /* get device number early */
822 if (dev->adapter->dev_get_device_id)
823 dev->adapter->dev_get_device_id(dev, &dev->device_number);
824
825 netdev_info(netdev, "attached to %s channel %u (device %u)\n",
826 peak_usb_adapter->name, ctrl_idx, dev->device_number);
827
828 return 0;
829
830 lbl_unregister_candev:
831 unregister_candev(netdev);
832
833 lbl_restore_intf_data:
834 usb_set_intfdata(intf, dev->prev_siblings);
835 kfree(dev->cmd_buf);
836
837 lbl_free_candev:
838 free_candev(netdev);
839
840 return err;
841 }
842
843 /*
844 * called by the usb core when the device is unplugged from the system
845 */
peak_usb_disconnect(struct usb_interface * intf)846 static void peak_usb_disconnect(struct usb_interface *intf)
847 {
848 struct peak_usb_device *dev;
849 struct peak_usb_device *dev_prev_siblings;
850
851 /* unregister as many netdev devices as siblings */
852 for (dev = usb_get_intfdata(intf); dev; dev = dev_prev_siblings) {
853 struct net_device *netdev = dev->netdev;
854 char name[IFNAMSIZ];
855
856 dev_prev_siblings = dev->prev_siblings;
857 dev->state &= ~PCAN_USB_STATE_CONNECTED;
858 strlcpy(name, netdev->name, IFNAMSIZ);
859
860 unregister_netdev(netdev);
861
862 kfree(dev->cmd_buf);
863 dev->next_siblings = NULL;
864 if (dev->adapter->dev_free)
865 dev->adapter->dev_free(dev);
866
867 free_candev(netdev);
868 dev_info(&intf->dev, "%s removed\n", name);
869 }
870
871 usb_set_intfdata(intf, NULL);
872 }
873
874 /*
875 * probe function for new PEAK-System devices
876 */
peak_usb_probe(struct usb_interface * intf,const struct usb_device_id * id)877 static int peak_usb_probe(struct usb_interface *intf,
878 const struct usb_device_id *id)
879 {
880 struct usb_device *usb_dev = interface_to_usbdev(intf);
881 const u16 usb_id_product = le16_to_cpu(usb_dev->descriptor.idProduct);
882 const struct peak_usb_adapter *peak_usb_adapter = NULL;
883 int i, err = -ENOMEM;
884
885 /* get corresponding PCAN-USB adapter */
886 for (i = 0; i < ARRAY_SIZE(peak_usb_adapters_list); i++)
887 if (peak_usb_adapters_list[i]->device_id == usb_id_product) {
888 peak_usb_adapter = peak_usb_adapters_list[i];
889 break;
890 }
891
892 if (!peak_usb_adapter) {
893 /* should never come except device_id bad usage in this file */
894 pr_err("%s: didn't find device id. 0x%x in devices list\n",
895 PCAN_USB_DRIVER_NAME, usb_id_product);
896 return -ENODEV;
897 }
898
899 /* got corresponding adapter: check if it handles current interface */
900 if (peak_usb_adapter->intf_probe) {
901 err = peak_usb_adapter->intf_probe(intf);
902 if (err)
903 return err;
904 }
905
906 for (i = 0; i < peak_usb_adapter->ctrl_count; i++) {
907 err = peak_usb_create_dev(peak_usb_adapter, intf, i);
908 if (err) {
909 /* deregister already created devices */
910 peak_usb_disconnect(intf);
911 break;
912 }
913 }
914
915 return err;
916 }
917
918 /* usb specific object needed to register this driver with the usb subsystem */
919 static struct usb_driver peak_usb_driver = {
920 .name = PCAN_USB_DRIVER_NAME,
921 .disconnect = peak_usb_disconnect,
922 .probe = peak_usb_probe,
923 .id_table = peak_usb_table,
924 };
925
peak_usb_init(void)926 static int __init peak_usb_init(void)
927 {
928 int err;
929
930 /* register this driver with the USB subsystem */
931 err = usb_register(&peak_usb_driver);
932 if (err)
933 pr_err("%s: usb_register failed (err %d)\n",
934 PCAN_USB_DRIVER_NAME, err);
935
936 return err;
937 }
938
peak_usb_do_device_exit(struct device * d,void * arg)939 static int peak_usb_do_device_exit(struct device *d, void *arg)
940 {
941 struct usb_interface *intf = to_usb_interface(d);
942 struct peak_usb_device *dev;
943
944 /* stop as many netdev devices as siblings */
945 for (dev = usb_get_intfdata(intf); dev; dev = dev->prev_siblings) {
946 struct net_device *netdev = dev->netdev;
947
948 if (netif_device_present(netdev))
949 if (dev->adapter->dev_exit)
950 dev->adapter->dev_exit(dev);
951 }
952
953 return 0;
954 }
955
peak_usb_exit(void)956 static void __exit peak_usb_exit(void)
957 {
958 int err;
959
960 /* last chance do send any synchronous commands here */
961 err = driver_for_each_device(&peak_usb_driver.drvwrap.driver, NULL,
962 NULL, peak_usb_do_device_exit);
963 if (err)
964 pr_err("%s: failed to stop all can devices (err %d)\n",
965 PCAN_USB_DRIVER_NAME, err);
966
967 /* deregister this driver with the USB subsystem */
968 usb_deregister(&peak_usb_driver);
969
970 pr_info("%s: PCAN-USB interfaces driver unloaded\n",
971 PCAN_USB_DRIVER_NAME);
972 }
973
974 module_init(peak_usb_init);
975 module_exit(peak_usb_exit);
976
