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/device.h>
12 #include <linux/ethtool.h>
13 #include <linux/init.h>
14 #include <linux/module.h>
15 #include <linux/netdevice.h>
16 #include <linux/signal.h>
17 #include <linux/slab.h>
18 #include <linux/sysfs.h>
19 #include <linux/usb.h>
20
21 #include <linux/can.h>
22 #include <linux/can/dev.h>
23 #include <linux/can/error.h>
24
25 #include "pcan_usb_core.h"
26
27 MODULE_AUTHOR("Stephane Grosjean <s.grosjean@peak-system.com>");
28 MODULE_DESCRIPTION("CAN driver for PEAK-System USB adapters");
29 MODULE_LICENSE("GPL v2");
30
31 /* Table of devices that work with this driver */
32 static const struct usb_device_id peak_usb_table[] = {
33 {
34 USB_DEVICE(PCAN_USB_VENDOR_ID, PCAN_USB_PRODUCT_ID),
35 .driver_info = (kernel_ulong_t)&pcan_usb,
36 }, {
37 USB_DEVICE(PCAN_USB_VENDOR_ID, PCAN_USBPRO_PRODUCT_ID),
38 .driver_info = (kernel_ulong_t)&pcan_usb_pro,
39 }, {
40 USB_DEVICE(PCAN_USB_VENDOR_ID, PCAN_USBFD_PRODUCT_ID),
41 .driver_info = (kernel_ulong_t)&pcan_usb_fd,
42 }, {
43 USB_DEVICE(PCAN_USB_VENDOR_ID, PCAN_USBPROFD_PRODUCT_ID),
44 .driver_info = (kernel_ulong_t)&pcan_usb_pro_fd,
45 }, {
46 USB_DEVICE(PCAN_USB_VENDOR_ID, PCAN_USBCHIP_PRODUCT_ID),
47 .driver_info = (kernel_ulong_t)&pcan_usb_chip,
48 }, {
49 USB_DEVICE(PCAN_USB_VENDOR_ID, PCAN_USBX6_PRODUCT_ID),
50 .driver_info = (kernel_ulong_t)&pcan_usb_x6,
51 }, {
52 /* Terminating entry */
53 }
54 };
55
56 MODULE_DEVICE_TABLE(usb, peak_usb_table);
57
can_channel_id_show(struct device * dev,struct device_attribute * attr,char * buf)58 static ssize_t can_channel_id_show(struct device *dev, struct device_attribute *attr, char *buf)
59 {
60 struct net_device *netdev = to_net_dev(dev);
61 struct peak_usb_device *peak_dev = netdev_priv(netdev);
62
63 return sysfs_emit(buf, "%08X\n", peak_dev->can_channel_id);
64 }
65 static DEVICE_ATTR_RO(can_channel_id);
66
67 /* mutable to avoid cast in attribute_group */
68 static struct attribute *peak_usb_sysfs_attrs[] = {
69 &dev_attr_can_channel_id.attr,
70 NULL,
71 };
72
73 static const struct attribute_group peak_usb_sysfs_group = {
74 .name = "peak_usb",
75 .attrs = peak_usb_sysfs_attrs,
76 };
77
78 /*
79 * dump memory
80 */
81 #define DUMP_WIDTH 16
pcan_dump_mem(const char * prompt,const void * p,int l)82 void pcan_dump_mem(const char *prompt, const void *p, int l)
83 {
84 pr_info("%s dumping %s (%d bytes):\n",
85 PCAN_USB_DRIVER_NAME, prompt ? prompt : "memory", l);
86 print_hex_dump(KERN_INFO, PCAN_USB_DRIVER_NAME " ", DUMP_PREFIX_NONE,
87 DUMP_WIDTH, 1, p, l, false);
88 }
89
90 /*
91 * initialize a time_ref object with usb adapter own settings
92 */
peak_usb_init_time_ref(struct peak_time_ref * time_ref,const struct peak_usb_adapter * adapter)93 void peak_usb_init_time_ref(struct peak_time_ref *time_ref,
94 const struct peak_usb_adapter *adapter)
95 {
96 if (time_ref) {
97 memset(time_ref, 0, sizeof(struct peak_time_ref));
98 time_ref->adapter = adapter;
99 }
100 }
101
102 /*
103 * sometimes, another now may be more recent than current one...
104 */
peak_usb_update_ts_now(struct peak_time_ref * time_ref,u32 ts_now)105 void peak_usb_update_ts_now(struct peak_time_ref *time_ref, u32 ts_now)
106 {
107 time_ref->ts_dev_2 = ts_now;
108
109 /* should wait at least two passes before computing */
110 if (ktime_to_ns(time_ref->tv_host) > 0) {
111 u32 delta_ts = time_ref->ts_dev_2 - time_ref->ts_dev_1;
112
113 if (time_ref->ts_dev_2 < time_ref->ts_dev_1)
114 delta_ts &= (1 << time_ref->adapter->ts_used_bits) - 1;
115
116 time_ref->ts_total += delta_ts;
117 }
118 }
119
120 /*
121 * register device timestamp as now
122 */
peak_usb_set_ts_now(struct peak_time_ref * time_ref,u32 ts_now)123 void peak_usb_set_ts_now(struct peak_time_ref *time_ref, u32 ts_now)
124 {
125 if (ktime_to_ns(time_ref->tv_host_0) == 0) {
126 /* use monotonic clock to correctly compute further deltas */
127 time_ref->tv_host_0 = ktime_get();
128 time_ref->tv_host = ktime_set(0, 0);
129 } else {
130 /*
131 * delta_us should not be >= 2^32 => delta should be < 4294s
132 * handle 32-bits wrapping here: if count of s. reaches 4200,
133 * reset counters and change time base
134 */
135 if (ktime_to_ns(time_ref->tv_host)) {
136 ktime_t delta = ktime_sub(time_ref->tv_host,
137 time_ref->tv_host_0);
138 if (ktime_to_ns(delta) > (4200ull * NSEC_PER_SEC)) {
139 time_ref->tv_host_0 = time_ref->tv_host;
140 time_ref->ts_total = 0;
141 }
142 }
143
144 time_ref->tv_host = ktime_get();
145 time_ref->tick_count++;
146 }
147
148 time_ref->ts_dev_1 = time_ref->ts_dev_2;
149 peak_usb_update_ts_now(time_ref, ts_now);
150 }
151
152 /*
153 * compute time according to current ts and time_ref data
154 */
peak_usb_get_ts_time(struct peak_time_ref * time_ref,u32 ts,ktime_t * time)155 void peak_usb_get_ts_time(struct peak_time_ref *time_ref, u32 ts, ktime_t *time)
156 {
157 /* protect from getting time before setting now */
158 if (ktime_to_ns(time_ref->tv_host)) {
159 u64 delta_us;
160 s64 delta_ts = 0;
161
162 /* General case: dev_ts_1 < dev_ts_2 < ts, with:
163 *
164 * - dev_ts_1 = previous sync timestamp
165 * - dev_ts_2 = last sync timestamp
166 * - ts = event timestamp
167 * - ts_period = known sync period (theoretical)
168 * ~ dev_ts2 - dev_ts1
169 * *but*:
170 *
171 * - time counters wrap (see adapter->ts_used_bits)
172 * - sometimes, dev_ts_1 < ts < dev_ts2
173 *
174 * "normal" case (sync time counters increase):
175 * must take into account case when ts wraps (tsw)
176 *
177 * < ts_period > < >
178 * | | |
179 * ---+--------+----+-------0-+--+-->
180 * ts_dev_1 | ts_dev_2 |
181 * ts tsw
182 */
183 if (time_ref->ts_dev_1 < time_ref->ts_dev_2) {
184 /* case when event time (tsw) wraps */
185 if (ts < time_ref->ts_dev_1)
186 delta_ts = BIT_ULL(time_ref->adapter->ts_used_bits);
187
188 /* Otherwise, sync time counter (ts_dev_2) has wrapped:
189 * handle case when event time (tsn) hasn't.
190 *
191 * < ts_period > < >
192 * | | |
193 * ---+--------+--0-+---------+--+-->
194 * ts_dev_1 | ts_dev_2 |
195 * tsn ts
196 */
197 } else if (time_ref->ts_dev_1 < ts) {
198 delta_ts = -BIT_ULL(time_ref->adapter->ts_used_bits);
199 }
200
201 /* add delay between last sync and event timestamps */
202 delta_ts += (signed int)(ts - time_ref->ts_dev_2);
203
204 /* add time from beginning to last sync */
205 delta_ts += time_ref->ts_total;
206
207 /* convert ticks number into microseconds */
208 delta_us = delta_ts * time_ref->adapter->us_per_ts_scale;
209 delta_us >>= time_ref->adapter->us_per_ts_shift;
210
211 *time = ktime_add_us(time_ref->tv_host_0, delta_us);
212 } else {
213 *time = ktime_get();
214 }
215 }
216
217 /* post received skb with native 64-bit hw timestamp */
peak_usb_netif_rx_64(struct sk_buff * skb,u32 ts_low,u32 ts_high)218 int peak_usb_netif_rx_64(struct sk_buff *skb, u32 ts_low, u32 ts_high)
219 {
220 struct skb_shared_hwtstamps *hwts = skb_hwtstamps(skb);
221 u64 ns_ts;
222
223 ns_ts = (u64)ts_high << 32 | ts_low;
224 ns_ts *= NSEC_PER_USEC;
225 hwts->hwtstamp = ns_to_ktime(ns_ts);
226
227 return netif_rx(skb);
228 }
229
230 /*
231 * callback for bulk Rx urb
232 */
peak_usb_read_bulk_callback(struct urb * urb)233 static void peak_usb_read_bulk_callback(struct urb *urb)
234 {
235 struct peak_usb_device *dev = urb->context;
236 struct net_device *netdev;
237 int err;
238
239 netdev = dev->netdev;
240
241 if (!netif_device_present(netdev))
242 return;
243
244 /* check reception status */
245 switch (urb->status) {
246 case 0:
247 /* success */
248 break;
249
250 case -EILSEQ:
251 case -ENOENT:
252 case -ECONNRESET:
253 case -ESHUTDOWN:
254 return;
255
256 default:
257 if (net_ratelimit())
258 netdev_err(netdev,
259 "Rx urb aborted (%d)\n", urb->status);
260 goto resubmit_urb;
261 }
262
263 /* protect from any incoming empty msgs */
264 if ((urb->actual_length > 0) && (dev->adapter->dev_decode_buf)) {
265 /* handle these kinds of msgs only if _start callback called */
266 if (dev->state & PCAN_USB_STATE_STARTED) {
267 err = dev->adapter->dev_decode_buf(dev, urb);
268 if (err)
269 pcan_dump_mem("received usb message",
270 urb->transfer_buffer,
271 urb->transfer_buffer_length);
272 }
273 }
274
275 resubmit_urb:
276 usb_fill_bulk_urb(urb, dev->udev,
277 usb_rcvbulkpipe(dev->udev, dev->ep_msg_in),
278 urb->transfer_buffer, dev->adapter->rx_buffer_size,
279 peak_usb_read_bulk_callback, dev);
280
281 usb_anchor_urb(urb, &dev->rx_submitted);
282 err = usb_submit_urb(urb, GFP_ATOMIC);
283 if (!err)
284 return;
285
286 usb_unanchor_urb(urb);
287
288 if (err == -ENODEV)
289 netif_device_detach(netdev);
290 else
291 netdev_err(netdev, "failed resubmitting read bulk urb: %d\n",
292 err);
293 }
294
295 /*
296 * callback for bulk Tx urb
297 */
peak_usb_write_bulk_callback(struct urb * urb)298 static void peak_usb_write_bulk_callback(struct urb *urb)
299 {
300 struct peak_tx_urb_context *context = urb->context;
301 struct peak_usb_device *dev;
302 struct net_device *netdev;
303 int tx_bytes;
304
305 BUG_ON(!context);
306
307 dev = context->dev;
308 netdev = dev->netdev;
309
310 atomic_dec(&dev->active_tx_urbs);
311
312 if (!netif_device_present(netdev))
313 return;
314
315 /* check tx status */
316 switch (urb->status) {
317 case 0:
318 /* prevent tx timeout */
319 netif_trans_update(netdev);
320 break;
321
322 case -EPROTO:
323 case -ENOENT:
324 case -ECONNRESET:
325 case -ESHUTDOWN:
326 break;
327
328 default:
329 if (net_ratelimit())
330 netdev_err(netdev, "Tx urb aborted (%d)\n",
331 urb->status);
332 break;
333 }
334
335 /* should always release echo skb and corresponding context */
336 tx_bytes = can_get_echo_skb(netdev, context->echo_index, NULL);
337 context->echo_index = PCAN_USB_MAX_TX_URBS;
338
339 if (!urb->status) {
340 /* transmission complete */
341 netdev->stats.tx_packets++;
342 netdev->stats.tx_bytes += tx_bytes;
343
344 /* do wakeup tx queue in case of success only */
345 netif_wake_queue(netdev);
346 }
347 }
348
349 /*
350 * called by netdev to send one skb on the CAN interface.
351 */
peak_usb_ndo_start_xmit(struct sk_buff * skb,struct net_device * netdev)352 static netdev_tx_t peak_usb_ndo_start_xmit(struct sk_buff *skb,
353 struct net_device *netdev)
354 {
355 struct peak_usb_device *dev = netdev_priv(netdev);
356 struct peak_tx_urb_context *context = NULL;
357 struct net_device_stats *stats = &netdev->stats;
358 struct urb *urb;
359 u8 *obuf;
360 int i, err;
361 size_t size = dev->adapter->tx_buffer_size;
362
363 if (can_dev_dropped_skb(netdev, skb))
364 return NETDEV_TX_OK;
365
366 for (i = 0; i < PCAN_USB_MAX_TX_URBS; i++)
367 if (dev->tx_contexts[i].echo_index == PCAN_USB_MAX_TX_URBS) {
368 context = dev->tx_contexts + i;
369 break;
370 }
371
372 if (!context) {
373 /* should not occur except during restart */
374 return NETDEV_TX_BUSY;
375 }
376
377 urb = context->urb;
378 obuf = urb->transfer_buffer;
379
380 err = dev->adapter->dev_encode_msg(dev, skb, obuf, &size);
381 if (err) {
382 if (net_ratelimit())
383 netdev_err(netdev, "packet dropped\n");
384 dev_kfree_skb(skb);
385 stats->tx_dropped++;
386 return NETDEV_TX_OK;
387 }
388
389 context->echo_index = i;
390
391 usb_anchor_urb(urb, &dev->tx_submitted);
392
393 can_put_echo_skb(skb, netdev, context->echo_index, 0);
394
395 atomic_inc(&dev->active_tx_urbs);
396
397 err = usb_submit_urb(urb, GFP_ATOMIC);
398 if (err) {
399 can_free_echo_skb(netdev, context->echo_index, NULL);
400
401 usb_unanchor_urb(urb);
402
403 /* this context is not used in fact */
404 context->echo_index = PCAN_USB_MAX_TX_URBS;
405
406 atomic_dec(&dev->active_tx_urbs);
407
408 switch (err) {
409 case -ENODEV:
410 netif_device_detach(netdev);
411 break;
412 default:
413 netdev_warn(netdev, "tx urb submitting failed err=%d\n",
414 err);
415 fallthrough;
416 case -ENOENT:
417 /* cable unplugged */
418 stats->tx_dropped++;
419 }
420 } else {
421 netif_trans_update(netdev);
422
423 /* slow down tx path */
424 if (atomic_read(&dev->active_tx_urbs) >= PCAN_USB_MAX_TX_URBS)
425 netif_stop_queue(netdev);
426 }
427
428 return NETDEV_TX_OK;
429 }
430
431 /*
432 * start the CAN interface.
433 * Rx and Tx urbs are allocated here. Rx urbs are submitted here.
434 */
peak_usb_start(struct peak_usb_device * dev)435 static int peak_usb_start(struct peak_usb_device *dev)
436 {
437 struct net_device *netdev = dev->netdev;
438 int err, i;
439
440 for (i = 0; i < PCAN_USB_MAX_RX_URBS; i++) {
441 struct urb *urb;
442 u8 *buf;
443
444 /* create a URB, and a buffer for it, to receive usb messages */
445 urb = usb_alloc_urb(0, GFP_KERNEL);
446 if (!urb) {
447 err = -ENOMEM;
448 break;
449 }
450
451 buf = kmalloc(dev->adapter->rx_buffer_size, GFP_KERNEL);
452 if (!buf) {
453 usb_free_urb(urb);
454 err = -ENOMEM;
455 break;
456 }
457
458 usb_fill_bulk_urb(urb, dev->udev,
459 usb_rcvbulkpipe(dev->udev, dev->ep_msg_in),
460 buf, dev->adapter->rx_buffer_size,
461 peak_usb_read_bulk_callback, dev);
462
463 /* ask last usb_free_urb() to also kfree() transfer_buffer */
464 urb->transfer_flags |= URB_FREE_BUFFER;
465 usb_anchor_urb(urb, &dev->rx_submitted);
466
467 err = usb_submit_urb(urb, GFP_KERNEL);
468 if (err) {
469 if (err == -ENODEV)
470 netif_device_detach(dev->netdev);
471
472 usb_unanchor_urb(urb);
473 kfree(buf);
474 usb_free_urb(urb);
475 break;
476 }
477
478 /* drop reference, USB core will take care of freeing it */
479 usb_free_urb(urb);
480 }
481
482 /* did we submit any URBs? Warn if we was not able to submit all urbs */
483 if (i < PCAN_USB_MAX_RX_URBS) {
484 if (i == 0) {
485 netdev_err(netdev, "couldn't setup any rx URB\n");
486 return err;
487 }
488
489 netdev_warn(netdev, "rx performance may be slow\n");
490 }
491
492 /* pre-alloc tx buffers and corresponding urbs */
493 for (i = 0; i < PCAN_USB_MAX_TX_URBS; i++) {
494 struct peak_tx_urb_context *context;
495 struct urb *urb;
496 u8 *buf;
497
498 /* create a URB and a buffer for it, to transmit usb messages */
499 urb = usb_alloc_urb(0, GFP_KERNEL);
500 if (!urb) {
501 err = -ENOMEM;
502 break;
503 }
504
505 buf = kmalloc(dev->adapter->tx_buffer_size, GFP_KERNEL);
506 if (!buf) {
507 usb_free_urb(urb);
508 err = -ENOMEM;
509 break;
510 }
511
512 context = dev->tx_contexts + i;
513 context->dev = dev;
514 context->urb = urb;
515
516 usb_fill_bulk_urb(urb, dev->udev,
517 usb_sndbulkpipe(dev->udev, dev->ep_msg_out),
518 buf, dev->adapter->tx_buffer_size,
519 peak_usb_write_bulk_callback, context);
520
521 /* ask last usb_free_urb() to also kfree() transfer_buffer */
522 urb->transfer_flags |= URB_FREE_BUFFER;
523 }
524
525 /* warn if we were not able to allocate enough tx contexts */
526 if (i < PCAN_USB_MAX_TX_URBS) {
527 if (i == 0) {
528 netdev_err(netdev, "couldn't setup any tx URB\n");
529 goto err_tx;
530 }
531
532 netdev_warn(netdev, "tx performance may be slow\n");
533 }
534
535 if (dev->adapter->dev_start) {
536 err = dev->adapter->dev_start(dev);
537 if (err)
538 goto err_adapter;
539 }
540
541 dev->state |= PCAN_USB_STATE_STARTED;
542
543 /* can set bus on now */
544 if (dev->adapter->dev_set_bus) {
545 err = dev->adapter->dev_set_bus(dev, 1);
546 if (err)
547 goto err_adapter;
548 }
549
550 dev->can.state = CAN_STATE_ERROR_ACTIVE;
551
552 return 0;
553
554 err_adapter:
555 if (err == -ENODEV)
556 netif_device_detach(dev->netdev);
557
558 netdev_warn(netdev, "couldn't submit control: %d\n", err);
559
560 for (i = 0; i < PCAN_USB_MAX_TX_URBS; i++) {
561 usb_free_urb(dev->tx_contexts[i].urb);
562 dev->tx_contexts[i].urb = NULL;
563 }
564 err_tx:
565 usb_kill_anchored_urbs(&dev->rx_submitted);
566
567 return err;
568 }
569
570 /*
571 * called by netdev to open the corresponding CAN interface.
572 */
peak_usb_ndo_open(struct net_device * netdev)573 static int peak_usb_ndo_open(struct net_device *netdev)
574 {
575 struct peak_usb_device *dev = netdev_priv(netdev);
576 int err;
577
578 /* common open */
579 err = open_candev(netdev);
580 if (err)
581 return err;
582
583 /* finally start device */
584 err = peak_usb_start(dev);
585 if (err) {
586 netdev_err(netdev, "couldn't start device: %d\n", err);
587 close_candev(netdev);
588 return err;
589 }
590
591 netif_start_queue(netdev);
592
593 return 0;
594 }
595
596 /*
597 * unlink in-flight Rx and Tx urbs and free their memory.
598 */
peak_usb_unlink_all_urbs(struct peak_usb_device * dev)599 static void peak_usb_unlink_all_urbs(struct peak_usb_device *dev)
600 {
601 int i;
602
603 /* free all Rx (submitted) urbs */
604 usb_kill_anchored_urbs(&dev->rx_submitted);
605
606 /* free unsubmitted Tx urbs first */
607 for (i = 0; i < PCAN_USB_MAX_TX_URBS; i++) {
608 struct urb *urb = dev->tx_contexts[i].urb;
609
610 if (!urb ||
611 dev->tx_contexts[i].echo_index != PCAN_USB_MAX_TX_URBS) {
612 /*
613 * this urb is already released or always submitted,
614 * let usb core free by itself
615 */
616 continue;
617 }
618
619 usb_free_urb(urb);
620 dev->tx_contexts[i].urb = NULL;
621 }
622
623 /* then free all submitted Tx urbs */
624 usb_kill_anchored_urbs(&dev->tx_submitted);
625 atomic_set(&dev->active_tx_urbs, 0);
626 }
627
628 /*
629 * called by netdev to close the corresponding CAN interface.
630 */
peak_usb_ndo_stop(struct net_device * netdev)631 static int peak_usb_ndo_stop(struct net_device *netdev)
632 {
633 struct peak_usb_device *dev = netdev_priv(netdev);
634
635 dev->state &= ~PCAN_USB_STATE_STARTED;
636 netif_stop_queue(netdev);
637
638 close_candev(netdev);
639
640 dev->can.state = CAN_STATE_STOPPED;
641
642 /* unlink all pending urbs and free used memory */
643 peak_usb_unlink_all_urbs(dev);
644
645 if (dev->adapter->dev_stop)
646 dev->adapter->dev_stop(dev);
647
648 /* can set bus off now */
649 if (dev->adapter->dev_set_bus) {
650 int err = dev->adapter->dev_set_bus(dev, 0);
651
652 if (err)
653 return err;
654 }
655
656 return 0;
657 }
658
659 /*
660 * handle end of waiting for the device to reset
661 */
peak_usb_restart_complete(struct peak_usb_device * dev)662 void peak_usb_restart_complete(struct peak_usb_device *dev)
663 {
664 /* finally MUST update can state */
665 dev->can.state = CAN_STATE_ERROR_ACTIVE;
666
667 /* netdev queue can be awaken now */
668 netif_wake_queue(dev->netdev);
669 }
670
peak_usb_async_complete(struct urb * urb)671 void peak_usb_async_complete(struct urb *urb)
672 {
673 kfree(urb->transfer_buffer);
674 usb_free_urb(urb);
675 }
676
677 /*
678 * device (auto-)restart mechanism runs in a timer context =>
679 * MUST handle restart with asynchronous usb transfers
680 */
peak_usb_restart(struct peak_usb_device * dev)681 static int peak_usb_restart(struct peak_usb_device *dev)
682 {
683 struct urb *urb;
684 int err;
685 u8 *buf;
686
687 /*
688 * if device doesn't define any asynchronous restart handler, simply
689 * wake the netdev queue up
690 */
691 if (!dev->adapter->dev_restart_async) {
692 peak_usb_restart_complete(dev);
693 return 0;
694 }
695
696 /* first allocate a urb to handle the asynchronous steps */
697 urb = usb_alloc_urb(0, GFP_ATOMIC);
698 if (!urb)
699 return -ENOMEM;
700
701 /* also allocate enough space for the commands to send */
702 buf = kmalloc(PCAN_USB_MAX_CMD_LEN, GFP_ATOMIC);
703 if (!buf) {
704 usb_free_urb(urb);
705 return -ENOMEM;
706 }
707
708 /* call the device specific handler for the restart */
709 err = dev->adapter->dev_restart_async(dev, urb, buf);
710 if (!err)
711 return 0;
712
713 kfree(buf);
714 usb_free_urb(urb);
715
716 return err;
717 }
718
719 /*
720 * candev callback used to change CAN mode.
721 * Warning: this is called from a timer context!
722 */
peak_usb_set_mode(struct net_device * netdev,enum can_mode mode)723 static int peak_usb_set_mode(struct net_device *netdev, enum can_mode mode)
724 {
725 struct peak_usb_device *dev = netdev_priv(netdev);
726 int err = 0;
727
728 switch (mode) {
729 case CAN_MODE_START:
730 err = peak_usb_restart(dev);
731 if (err)
732 netdev_err(netdev, "couldn't start device (err %d)\n",
733 err);
734 break;
735
736 default:
737 return -EOPNOTSUPP;
738 }
739
740 return err;
741 }
742
743 /*
744 * candev callback used to set device nominal/arbitration bitrate.
745 */
peak_usb_set_bittiming(struct net_device * netdev)746 static int peak_usb_set_bittiming(struct net_device *netdev)
747 {
748 struct peak_usb_device *dev = netdev_priv(netdev);
749 const struct peak_usb_adapter *pa = dev->adapter;
750
751 if (pa->dev_set_bittiming) {
752 struct can_bittiming *bt = &dev->can.bittiming;
753 int err = pa->dev_set_bittiming(dev, bt);
754
755 if (err)
756 netdev_info(netdev, "couldn't set bitrate (err %d)\n",
757 err);
758 return err;
759 }
760
761 return 0;
762 }
763
764 /*
765 * candev callback used to set device data bitrate.
766 */
peak_usb_set_data_bittiming(struct net_device * netdev)767 static int peak_usb_set_data_bittiming(struct net_device *netdev)
768 {
769 struct peak_usb_device *dev = netdev_priv(netdev);
770 const struct peak_usb_adapter *pa = dev->adapter;
771
772 if (pa->dev_set_data_bittiming) {
773 struct can_bittiming *bt = &dev->can.data_bittiming;
774 int err = pa->dev_set_data_bittiming(dev, bt);
775
776 if (err)
777 netdev_info(netdev,
778 "couldn't set data bitrate (err %d)\n",
779 err);
780
781 return err;
782 }
783
784 return 0;
785 }
786
peak_eth_ioctl(struct net_device * netdev,struct ifreq * ifr,int cmd)787 static int peak_eth_ioctl(struct net_device *netdev, struct ifreq *ifr, int cmd)
788 {
789 struct hwtstamp_config hwts_cfg = { 0 };
790
791 switch (cmd) {
792 case SIOCSHWTSTAMP: /* set */
793 if (copy_from_user(&hwts_cfg, ifr->ifr_data, sizeof(hwts_cfg)))
794 return -EFAULT;
795 if (hwts_cfg.tx_type == HWTSTAMP_TX_OFF &&
796 hwts_cfg.rx_filter == HWTSTAMP_FILTER_ALL)
797 return 0;
798 return -ERANGE;
799
800 case SIOCGHWTSTAMP: /* get */
801 hwts_cfg.tx_type = HWTSTAMP_TX_OFF;
802 hwts_cfg.rx_filter = HWTSTAMP_FILTER_ALL;
803 if (copy_to_user(ifr->ifr_data, &hwts_cfg, sizeof(hwts_cfg)))
804 return -EFAULT;
805 return 0;
806
807 default:
808 return -EOPNOTSUPP;
809 }
810 }
811
812 static const struct net_device_ops peak_usb_netdev_ops = {
813 .ndo_open = peak_usb_ndo_open,
814 .ndo_stop = peak_usb_ndo_stop,
815 .ndo_eth_ioctl = peak_eth_ioctl,
816 .ndo_start_xmit = peak_usb_ndo_start_xmit,
817 .ndo_change_mtu = can_change_mtu,
818 };
819
820 /* CAN-USB devices generally handle 32-bit CAN channel IDs.
821 * In case one doesn't, then it have to overload this function.
822 */
peak_usb_get_eeprom_len(struct net_device * netdev)823 int peak_usb_get_eeprom_len(struct net_device *netdev)
824 {
825 return sizeof(u32);
826 }
827
828 /* Every CAN-USB device exports the dev_get_can_channel_id() operation. It is used
829 * here to fill the data buffer with the user defined CAN channel ID.
830 */
peak_usb_get_eeprom(struct net_device * netdev,struct ethtool_eeprom * eeprom,u8 * data)831 int peak_usb_get_eeprom(struct net_device *netdev,
832 struct ethtool_eeprom *eeprom, u8 *data)
833 {
834 struct peak_usb_device *dev = netdev_priv(netdev);
835 u32 ch_id;
836 __le32 ch_id_le;
837 int err;
838
839 err = dev->adapter->dev_get_can_channel_id(dev, &ch_id);
840 if (err)
841 return err;
842
843 /* ethtool operates on individual bytes. The byte order of the CAN
844 * channel id in memory depends on the kernel architecture. We
845 * convert the CAN channel id back to the native byte order of the PEAK
846 * device itself to ensure that the order is consistent for all
847 * host architectures.
848 */
849 ch_id_le = cpu_to_le32(ch_id);
850 memcpy(data, (u8 *)&ch_id_le + eeprom->offset, eeprom->len);
851
852 /* update cached value */
853 dev->can_channel_id = ch_id;
854 return err;
855 }
856
857 /* Every CAN-USB device exports the dev_get_can_channel_id()/dev_set_can_channel_id()
858 * operations. They are used here to set the new user defined CAN channel ID.
859 */
peak_usb_set_eeprom(struct net_device * netdev,struct ethtool_eeprom * eeprom,u8 * data)860 int peak_usb_set_eeprom(struct net_device *netdev,
861 struct ethtool_eeprom *eeprom, u8 *data)
862 {
863 struct peak_usb_device *dev = netdev_priv(netdev);
864 u32 ch_id;
865 __le32 ch_id_le;
866 int err;
867
868 /* first, read the current user defined CAN channel ID */
869 err = dev->adapter->dev_get_can_channel_id(dev, &ch_id);
870 if (err) {
871 netdev_err(netdev, "Failed to init CAN channel id (err %d)\n", err);
872 return err;
873 }
874
875 /* do update the value with user given bytes.
876 * ethtool operates on individual bytes. The byte order of the CAN
877 * channel ID in memory depends on the kernel architecture. We
878 * convert the CAN channel ID back to the native byte order of the PEAK
879 * device itself to ensure that the order is consistent for all
880 * host architectures.
881 */
882 ch_id_le = cpu_to_le32(ch_id);
883 memcpy((u8 *)&ch_id_le + eeprom->offset, data, eeprom->len);
884 ch_id = le32_to_cpu(ch_id_le);
885
886 /* flash the new value now */
887 err = dev->adapter->dev_set_can_channel_id(dev, ch_id);
888 if (err) {
889 netdev_err(netdev, "Failed to write new CAN channel id (err %d)\n",
890 err);
891 return err;
892 }
893
894 /* update cached value with the new one */
895 dev->can_channel_id = ch_id;
896
897 return 0;
898 }
899
pcan_get_ts_info(struct net_device * dev,struct kernel_ethtool_ts_info * info)900 int pcan_get_ts_info(struct net_device *dev, struct kernel_ethtool_ts_info *info)
901 {
902 info->so_timestamping =
903 SOF_TIMESTAMPING_TX_SOFTWARE |
904 SOF_TIMESTAMPING_RX_HARDWARE |
905 SOF_TIMESTAMPING_RAW_HARDWARE;
906 info->tx_types = BIT(HWTSTAMP_TX_OFF);
907 info->rx_filters = BIT(HWTSTAMP_FILTER_ALL);
908
909 return 0;
910 }
911
912 /*
913 * create one device which is attached to CAN controller #ctrl_idx of the
914 * usb adapter.
915 */
peak_usb_create_dev(const struct peak_usb_adapter * peak_usb_adapter,struct usb_interface * intf,int ctrl_idx)916 static int peak_usb_create_dev(const struct peak_usb_adapter *peak_usb_adapter,
917 struct usb_interface *intf, int ctrl_idx)
918 {
919 struct usb_device *usb_dev = interface_to_usbdev(intf);
920 int sizeof_candev = peak_usb_adapter->sizeof_dev_private;
921 struct peak_usb_device *dev;
922 struct net_device *netdev;
923 int i, err;
924 u16 tmp16;
925
926 if (sizeof_candev < sizeof(struct peak_usb_device))
927 sizeof_candev = sizeof(struct peak_usb_device);
928
929 netdev = alloc_candev(sizeof_candev, PCAN_USB_MAX_TX_URBS);
930 if (!netdev) {
931 dev_err(&intf->dev, "%s: couldn't alloc candev\n",
932 PCAN_USB_DRIVER_NAME);
933 return -ENOMEM;
934 }
935
936 dev = netdev_priv(netdev);
937
938 /* allocate a buffer large enough to send commands */
939 dev->cmd_buf = kzalloc(PCAN_USB_MAX_CMD_LEN, GFP_KERNEL);
940 if (!dev->cmd_buf) {
941 err = -ENOMEM;
942 goto lbl_free_candev;
943 }
944
945 dev->udev = usb_dev;
946 dev->netdev = netdev;
947 dev->adapter = peak_usb_adapter;
948 dev->ctrl_idx = ctrl_idx;
949 dev->state = PCAN_USB_STATE_CONNECTED;
950
951 dev->ep_msg_in = peak_usb_adapter->ep_msg_in;
952 dev->ep_msg_out = peak_usb_adapter->ep_msg_out[ctrl_idx];
953
954 dev->can.clock = peak_usb_adapter->clock;
955 dev->can.bittiming_const = peak_usb_adapter->bittiming_const;
956 dev->can.do_set_bittiming = peak_usb_set_bittiming;
957 dev->can.data_bittiming_const = peak_usb_adapter->data_bittiming_const;
958 dev->can.do_set_data_bittiming = peak_usb_set_data_bittiming;
959 dev->can.do_set_mode = peak_usb_set_mode;
960 dev->can.do_get_berr_counter = peak_usb_adapter->do_get_berr_counter;
961 dev->can.ctrlmode_supported = peak_usb_adapter->ctrlmode_supported;
962
963 netdev->netdev_ops = &peak_usb_netdev_ops;
964
965 netdev->flags |= IFF_ECHO; /* we support local echo */
966
967 /* add ethtool support */
968 netdev->ethtool_ops = peak_usb_adapter->ethtool_ops;
969
970 /* register peak_usb sysfs files */
971 netdev->sysfs_groups[0] = &peak_usb_sysfs_group;
972
973 init_usb_anchor(&dev->rx_submitted);
974
975 init_usb_anchor(&dev->tx_submitted);
976 atomic_set(&dev->active_tx_urbs, 0);
977
978 for (i = 0; i < PCAN_USB_MAX_TX_URBS; i++)
979 dev->tx_contexts[i].echo_index = PCAN_USB_MAX_TX_URBS;
980
981 dev->prev_siblings = usb_get_intfdata(intf);
982 usb_set_intfdata(intf, dev);
983
984 SET_NETDEV_DEV(netdev, &intf->dev);
985 netdev->dev_id = ctrl_idx;
986
987 err = register_candev(netdev);
988 if (err) {
989 dev_err(&intf->dev, "couldn't register CAN device: %d\n", err);
990 goto lbl_restore_intf_data;
991 }
992
993 if (dev->prev_siblings)
994 (dev->prev_siblings)->next_siblings = dev;
995
996 /* keep hw revision into the netdevice */
997 tmp16 = le16_to_cpu(usb_dev->descriptor.bcdDevice);
998 dev->device_rev = tmp16 >> 8;
999
1000 if (dev->adapter->dev_init) {
1001 err = dev->adapter->dev_init(dev);
1002 if (err)
1003 goto lbl_unregister_candev;
1004 }
1005
1006 /* set bus off */
1007 if (dev->adapter->dev_set_bus) {
1008 err = dev->adapter->dev_set_bus(dev, 0);
1009 if (err)
1010 goto adap_dev_free;
1011 }
1012
1013 /* get CAN channel id early */
1014 dev->adapter->dev_get_can_channel_id(dev, &dev->can_channel_id);
1015
1016 netdev_info(netdev, "attached to %s channel %u (device 0x%08X)\n",
1017 peak_usb_adapter->name, ctrl_idx, dev->can_channel_id);
1018
1019 return 0;
1020
1021 adap_dev_free:
1022 if (dev->adapter->dev_free)
1023 dev->adapter->dev_free(dev);
1024
1025 lbl_unregister_candev:
1026 unregister_candev(netdev);
1027
1028 lbl_restore_intf_data:
1029 usb_set_intfdata(intf, dev->prev_siblings);
1030 kfree(dev->cmd_buf);
1031
1032 lbl_free_candev:
1033 free_candev(netdev);
1034
1035 return err;
1036 }
1037
1038 /*
1039 * called by the usb core when the device is unplugged from the system
1040 */
peak_usb_disconnect(struct usb_interface * intf)1041 static void peak_usb_disconnect(struct usb_interface *intf)
1042 {
1043 struct peak_usb_device *dev;
1044 struct peak_usb_device *dev_prev_siblings;
1045
1046 /* unregister as many netdev devices as siblings */
1047 for (dev = usb_get_intfdata(intf); dev; dev = dev_prev_siblings) {
1048 struct net_device *netdev = dev->netdev;
1049 char name[IFNAMSIZ];
1050
1051 dev_prev_siblings = dev->prev_siblings;
1052 dev->state &= ~PCAN_USB_STATE_CONNECTED;
1053 strscpy(name, netdev->name, IFNAMSIZ);
1054
1055 unregister_candev(netdev);
1056
1057 kfree(dev->cmd_buf);
1058 dev->next_siblings = NULL;
1059 if (dev->adapter->dev_free)
1060 dev->adapter->dev_free(dev);
1061
1062 free_candev(netdev);
1063 dev_info(&intf->dev, "%s removed\n", name);
1064 }
1065
1066 usb_set_intfdata(intf, NULL);
1067 }
1068
1069 /*
1070 * probe function for new PEAK-System devices
1071 */
peak_usb_probe(struct usb_interface * intf,const struct usb_device_id * id)1072 static int peak_usb_probe(struct usb_interface *intf,
1073 const struct usb_device_id *id)
1074 {
1075 const struct peak_usb_adapter *peak_usb_adapter;
1076 int i, err = -ENOMEM;
1077
1078 /* get corresponding PCAN-USB adapter */
1079 peak_usb_adapter = (const struct peak_usb_adapter *)id->driver_info;
1080
1081 /* got corresponding adapter: check if it handles current interface */
1082 if (peak_usb_adapter->intf_probe) {
1083 err = peak_usb_adapter->intf_probe(intf);
1084 if (err)
1085 return err;
1086 }
1087
1088 for (i = 0; i < peak_usb_adapter->ctrl_count; i++) {
1089 err = peak_usb_create_dev(peak_usb_adapter, intf, i);
1090 if (err) {
1091 /* deregister already created devices */
1092 peak_usb_disconnect(intf);
1093 break;
1094 }
1095 }
1096
1097 return err;
1098 }
1099
1100 /* usb specific object needed to register this driver with the usb subsystem */
1101 static struct usb_driver peak_usb_driver = {
1102 .name = PCAN_USB_DRIVER_NAME,
1103 .disconnect = peak_usb_disconnect,
1104 .probe = peak_usb_probe,
1105 .id_table = peak_usb_table,
1106 };
1107
peak_usb_init(void)1108 static int __init peak_usb_init(void)
1109 {
1110 int err;
1111
1112 /* register this driver with the USB subsystem */
1113 err = usb_register(&peak_usb_driver);
1114 if (err)
1115 pr_err("%s: usb_register failed (err %d)\n",
1116 PCAN_USB_DRIVER_NAME, err);
1117
1118 return err;
1119 }
1120
peak_usb_do_device_exit(struct device * d,void * arg)1121 static int peak_usb_do_device_exit(struct device *d, void *arg)
1122 {
1123 struct usb_interface *intf = to_usb_interface(d);
1124 struct peak_usb_device *dev;
1125
1126 /* stop as many netdev devices as siblings */
1127 for (dev = usb_get_intfdata(intf); dev; dev = dev->prev_siblings) {
1128 struct net_device *netdev = dev->netdev;
1129
1130 if (netif_device_present(netdev))
1131 if (dev->adapter->dev_exit)
1132 dev->adapter->dev_exit(dev);
1133 }
1134
1135 return 0;
1136 }
1137
peak_usb_exit(void)1138 static void __exit peak_usb_exit(void)
1139 {
1140 int err;
1141
1142 /* last chance do send any synchronous commands here */
1143 err = driver_for_each_device(&peak_usb_driver.driver, NULL,
1144 NULL, peak_usb_do_device_exit);
1145 if (err)
1146 pr_err("%s: failed to stop all can devices (err %d)\n",
1147 PCAN_USB_DRIVER_NAME, err);
1148
1149 /* deregister this driver with the USB subsystem */
1150 usb_deregister(&peak_usb_driver);
1151
1152 pr_info("%s: PCAN-USB interfaces driver unloaded\n",
1153 PCAN_USB_DRIVER_NAME);
1154 }
1155
1156 module_init(peak_usb_init);
1157 module_exit(peak_usb_exit);
1158