1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
|
/*
* CAN driver for PEAK System PCAN-USB adapter
* Derived from the PCAN project file driver/src/pcan_usb.c
*
* Copyright (C) 2003-2010 PEAK System-Technik GmbH
* Copyright (C) 2011-2012 Stephane Grosjean <s.grosjean@peak-system.com>
*
* Many thanks to Klaus Hitschler <klaus.hitschler@gmx.de>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published
* by the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*/
#include <linux/netdevice.h>
#include <linux/usb.h>
#include <linux/module.h>
#include <linux/can.h>
#include <linux/can/dev.h>
#include <linux/can/error.h>
#include "pcan_usb_core.h"
MODULE_SUPPORTED_DEVICE("PEAK-System PCAN-USB adapter");
/* PCAN-USB Endpoints */
#define PCAN_USB_EP_CMDOUT 1
#define PCAN_USB_EP_CMDIN (PCAN_USB_EP_CMDOUT | USB_DIR_IN)
#define PCAN_USB_EP_MSGOUT 2
#define PCAN_USB_EP_MSGIN (PCAN_USB_EP_MSGOUT | USB_DIR_IN)
/* PCAN-USB command struct */
#define PCAN_USB_CMD_FUNC 0
#define PCAN_USB_CMD_NUM 1
#define PCAN_USB_CMD_ARGS 2
#define PCAN_USB_CMD_ARGS_LEN 14
#define PCAN_USB_CMD_LEN (PCAN_USB_CMD_ARGS + \
PCAN_USB_CMD_ARGS_LEN)
/* PCAN-USB command timeout (ms.) */
#define PCAN_USB_COMMAND_TIMEOUT 1000
/* PCAN-USB startup timeout (ms.) */
#define PCAN_USB_STARTUP_TIMEOUT 10
/* PCAN-USB rx/tx buffers size */
#define PCAN_USB_RX_BUFFER_SIZE 64
#define PCAN_USB_TX_BUFFER_SIZE 64
#define PCAN_USB_MSG_HEADER_LEN 2
/* PCAN-USB adapter internal clock (MHz) */
#define PCAN_USB_CRYSTAL_HZ 16000000
/* PCAN-USB USB message record status/len field */
#define PCAN_USB_STATUSLEN_TIMESTAMP (1 << 7)
#define PCAN_USB_STATUSLEN_INTERNAL (1 << 6)
#define PCAN_USB_STATUSLEN_EXT_ID (1 << 5)
#define PCAN_USB_STATUSLEN_RTR (1 << 4)
#define PCAN_USB_STATUSLEN_DLC (0xf)
/* PCAN-USB error flags */
#define PCAN_USB_ERROR_TXFULL 0x01
#define PCAN_USB_ERROR_RXQOVR 0x02
#define PCAN_USB_ERROR_BUS_LIGHT 0x04
#define PCAN_USB_ERROR_BUS_HEAVY 0x08
#define PCAN_USB_ERROR_BUS_OFF 0x10
#define PCAN_USB_ERROR_RXQEMPTY 0x20
#define PCAN_USB_ERROR_QOVR 0x40
#define PCAN_USB_ERROR_TXQFULL 0x80
/* SJA1000 modes */
#define SJA1000_MODE_NORMAL 0x00
#define SJA1000_MODE_INIT 0x01
/*
* tick duration = 42.666 us =>
* (tick_number * 44739243) >> 20 ~ (tick_number * 42666) / 1000
* accuracy = 10^-7
*/
#define PCAN_USB_TS_DIV_SHIFTER 20
#define PCAN_USB_TS_US_PER_TICK 44739243
/* PCAN-USB messages record types */
#define PCAN_USB_REC_ERROR 1
#define PCAN_USB_REC_ANALOG 2
#define PCAN_USB_REC_BUSLOAD 3
#define PCAN_USB_REC_TS 4
#define PCAN_USB_REC_BUSEVT 5
/* private to PCAN-USB adapter */
struct pcan_usb {
struct peak_usb_device dev;
struct peak_time_ref time_ref;
struct timer_list restart_timer;
};
/* incoming message context for decoding */
struct pcan_usb_msg_context {
u16 ts16;
u8 prev_ts8;
u8 *ptr;
u8 *end;
u8 rec_cnt;
u8 rec_idx;
u8 rec_data_idx;
struct net_device *netdev;
struct pcan_usb *pdev;
};
/*
* send a command
*/
static int pcan_usb_send_cmd(struct peak_usb_device *dev, u8 f, u8 n, u8 *p)
{
int err;
int actual_length;
/* usb device unregistered? */
if (!(dev->state & PCAN_USB_STATE_CONNECTED))
return 0;
dev->cmd_buf[PCAN_USB_CMD_FUNC] = f;
dev->cmd_buf[PCAN_USB_CMD_NUM] = n;
if (p)
memcpy(dev->cmd_buf + PCAN_USB_CMD_ARGS,
p, PCAN_USB_CMD_ARGS_LEN);
err = usb_bulk_msg(dev->udev,
usb_sndbulkpipe(dev->udev, PCAN_USB_EP_CMDOUT),
dev->cmd_buf, PCAN_USB_CMD_LEN, &actual_length,
PCAN_USB_COMMAND_TIMEOUT);
if (err)
netdev_err(dev->netdev,
"sending cmd f=0x%x n=0x%x failure: %d\n",
f, n, err);
return err;
}
/*
* send a command then wait for its response
*/
static int pcan_usb_wait_rsp(struct peak_usb_device *dev, u8 f, u8 n, u8 *p)
{
int err;
int actual_length;
/* usb device unregistered? */
if (!(dev->state & PCAN_USB_STATE_CONNECTED))
return 0;
/* first, send command */
err = pcan_usb_send_cmd(dev, f, n, NULL);
if (err)
return err;
err = usb_bulk_msg(dev->udev,
usb_rcvbulkpipe(dev->udev, PCAN_USB_EP_CMDIN),
dev->cmd_buf, PCAN_USB_CMD_LEN, &actual_length,
PCAN_USB_COMMAND_TIMEOUT);
if (err)
netdev_err(dev->netdev,
"waiting rsp f=0x%x n=0x%x failure: %d\n", f, n, err);
else if (p)
memcpy(p, dev->cmd_buf + PCAN_USB_CMD_ARGS,
PCAN_USB_CMD_ARGS_LEN);
return err;
}
static int pcan_usb_set_sja1000(struct peak_usb_device *dev, u8 mode)
{
u8 args[PCAN_USB_CMD_ARGS_LEN] = {
[1] = mode,
};
return pcan_usb_send_cmd(dev, 9, 2, args);
}
static int pcan_usb_set_bus(struct peak_usb_device *dev, u8 onoff)
{
u8 args[PCAN_USB_CMD_ARGS_LEN] = {
[0] = !!onoff,
};
return pcan_usb_send_cmd(dev, 3, 2, args);
}
static int pcan_usb_set_silent(struct peak_usb_device *dev, u8 onoff)
{
u8 args[PCAN_USB_CMD_ARGS_LEN] = {
[0] = !!onoff,
};
return pcan_usb_send_cmd(dev, 3, 3, args);
}
static int pcan_usb_set_ext_vcc(struct peak_usb_device *dev, u8 onoff)
{
u8 args[PCAN_USB_CMD_ARGS_LEN] = {
[0] = !!onoff,
};
return pcan_usb_send_cmd(dev, 10, 2, args);
}
/*
* set bittiming value to can
*/
static int pcan_usb_set_bittiming(struct peak_usb_device *dev,
struct can_bittiming *bt)
{
u8 args[PCAN_USB_CMD_ARGS_LEN];
u8 btr0, btr1;
btr0 = ((bt->brp - 1) & 0x3f) | (((bt->sjw - 1) & 0x3) << 6);
btr1 = ((bt->prop_seg + bt->phase_seg1 - 1) & 0xf) |
(((bt->phase_seg2 - 1) & 0x7) << 4);
if (dev->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
btr1 |= 0x80;
netdev_info(dev->netdev, "setting BTR0=0x%02x BTR1=0x%02x\n",
btr0, btr1);
args[0] = btr1;
args[1] = btr0;
return pcan_usb_send_cmd(dev, 1, 2, args);
}
/*
* init/reset can
*/
static int pcan_usb_write_mode(struct peak_usb_device *dev, u8 onoff)
{
int err;
err = pcan_usb_set_bus(dev, onoff);
if (err)
return err;
if (!onoff) {
err = pcan_usb_set_sja1000(dev, SJA1000_MODE_INIT);
} else {
/* the PCAN-USB needs time to init */
set_current_state(TASK_INTERRUPTIBLE);
schedule_timeout(msecs_to_jiffies(PCAN_USB_STARTUP_TIMEOUT));
}
return err;
}
/*
* handle end of waiting for the device to reset
*/
static void pcan_usb_restart(struct timer_list *t)
{
struct pcan_usb *pdev = from_timer(pdev, t, restart_timer);
struct peak_usb_device *dev = &pdev->dev;
/* notify candev and netdev */
peak_usb_restart_complete(dev);
}
/*
* handle the submission of the restart urb
*/
static void pcan_usb_restart_pending(struct urb *urb)
{
struct pcan_usb *pdev = urb->context;
/* the PCAN-USB needs time to restart */
mod_timer(&pdev->restart_timer,
jiffies + msecs_to_jiffies(PCAN_USB_STARTUP_TIMEOUT));
/* can delete usb resources */
peak_usb_async_complete(urb);
}
/*
* handle asynchronous restart
*/
static int pcan_usb_restart_async(struct peak_usb_device *dev, struct urb *urb,
u8 *buf)
{
struct pcan_usb *pdev = container_of(dev, struct pcan_usb, dev);
if (timer_pending(&pdev->restart_timer))
return -EBUSY;
/* set bus on */
buf[PCAN_USB_CMD_FUNC] = 3;
buf[PCAN_USB_CMD_NUM] = 2;
buf[PCAN_USB_CMD_ARGS] = 1;
usb_fill_bulk_urb(urb, dev->udev,
usb_sndbulkpipe(dev->udev, PCAN_USB_EP_CMDOUT),
buf, PCAN_USB_CMD_LEN,
pcan_usb_restart_pending, pdev);
return usb_submit_urb(urb, GFP_ATOMIC);
}
/*
* read serial number from device
*/
static int pcan_usb_get_serial(struct peak_usb_device *dev, u32 *serial_number)
{
u8 args[PCAN_USB_CMD_ARGS_LEN];
int err;
err = pcan_usb_wait_rsp(dev, 6, 1, args);
if (err) {
netdev_err(dev->netdev, "getting serial failure: %d\n", err);
} else if (serial_number) {
__le32 tmp32;
memcpy(&tmp32, args, 4);
*serial_number = le32_to_cpu(tmp32);
}
return err;
}
/*
* read device id from device
*/
static int pcan_usb_get_device_id(struct peak_usb_device *dev, u32 *device_id)
{
u8 args[PCAN_USB_CMD_ARGS_LEN];
int err;
err = pcan_usb_wait_rsp(dev, 4, 1, args);
if (err)
netdev_err(dev->netdev, "getting device id failure: %d\n", err);
else if (device_id)
*device_id = args[0];
return err;
}
/*
* update current time ref with received timestamp
*/
static int pcan_usb_update_ts(struct pcan_usb_msg_context *mc)
{
__le16 tmp16;
if ((mc->ptr+2) > mc->end)
return -EINVAL;
memcpy(&tmp16, mc->ptr, 2);
mc->ts16 = le16_to_cpu(tmp16);
if (mc->rec_idx > 0)
peak_usb_update_ts_now(&mc->pdev->time_ref, mc->ts16);
else
peak_usb_set_ts_now(&mc->pdev->time_ref, mc->ts16);
return 0;
}
/*
* decode received timestamp
*/
static int pcan_usb_decode_ts(struct pcan_usb_msg_context *mc, u8 first_packet)
{
/* only 1st packet supplies a word timestamp */
if (first_packet) {
__le16 tmp16;
if ((mc->ptr + 2) > mc->end)
return -EINVAL;
memcpy(&tmp16, mc->ptr, 2);
mc->ptr += 2;
mc->ts16 = le16_to_cpu(tmp16);
mc->prev_ts8 = mc->ts16 & 0x00ff;
} else {
u8 ts8;
if ((mc->ptr + 1) > mc->end)
return -EINVAL;
ts8 = *mc->ptr++;
if (ts8 < mc->prev_ts8)
mc->ts16 += 0x100;
mc->ts16 &= 0xff00;
mc->ts16 |= ts8;
mc->prev_ts8 = ts8;
}
return 0;
}
static int pcan_usb_decode_error(struct pcan_usb_msg_context *mc, u8 n,
u8 status_len)
{
struct sk_buff *skb;
struct can_frame *cf;
enum can_state new_state;
/* ignore this error until 1st ts received */
if (n == PCAN_USB_ERROR_QOVR)
if (!mc->pdev->time_ref.tick_count)
return 0;
new_state = mc->pdev->dev.can.state;
switch (mc->pdev->dev.can.state) {
case CAN_STATE_ERROR_ACTIVE:
if (n & PCAN_USB_ERROR_BUS_LIGHT) {
new_state = CAN_STATE_ERROR_WARNING;
break;
}
case CAN_STATE_ERROR_WARNING:
if (n & PCAN_USB_ERROR_BUS_HEAVY) {
new_state = CAN_STATE_ERROR_PASSIVE;
break;
}
if (n & PCAN_USB_ERROR_BUS_OFF) {
new_state = CAN_STATE_BUS_OFF;
break;
}
if (n & (PCAN_USB_ERROR_RXQOVR | PCAN_USB_ERROR_QOVR)) {
/*
* trick to bypass next comparison and process other
* errors
*/
new_state = CAN_STATE_MAX;
break;
}
if ((n & PCAN_USB_ERROR_BUS_LIGHT) == 0) {
/* no error (back to active state) */
mc->pdev->dev.can.state = CAN_STATE_ERROR_ACTIVE;
return 0;
}
break;
case CAN_STATE_ERROR_PASSIVE:
if (n & PCAN_USB_ERROR_BUS_OFF) {
new_state = CAN_STATE_BUS_OFF;
break;
}
if (n & PCAN_USB_ERROR_BUS_LIGHT) {
new_state = CAN_STATE_ERROR_WARNING;
break;
}
if (n & (PCAN_USB_ERROR_RXQOVR | PCAN_USB_ERROR_QOVR)) {
/*
* trick to bypass next comparison and process other
* errors
*/
new_state = CAN_STATE_MAX;
break;
}
if ((n & PCAN_USB_ERROR_BUS_HEAVY) == 0) {
/* no error (back to active state) */
mc->pdev->dev.can.state = CAN_STATE_ERROR_ACTIVE;
return 0;
}
break;
default:
/* do nothing waiting for restart */
return 0;
}
/* donot post any error if current state didn't change */
if (mc->pdev->dev.can.state == new_state)
return 0;
/* allocate an skb to store the error frame */
skb = alloc_can_err_skb(mc->netdev, &cf);
if (!skb)
return -ENOMEM;
switch (new_state) {
case CAN_STATE_BUS_OFF:
cf->can_id |= CAN_ERR_BUSOFF;
mc->pdev->dev.can.can_stats.bus_off++;
can_bus_off(mc->netdev);
break;
case CAN_STATE_ERROR_PASSIVE:
cf->can_id |= CAN_ERR_CRTL;
cf->data[1] |= CAN_ERR_CRTL_TX_PASSIVE |
CAN_ERR_CRTL_RX_PASSIVE;
mc->pdev->dev.can.can_stats.error_passive++;
break;
case CAN_STATE_ERROR_WARNING:
cf->can_id |= CAN_ERR_CRTL;
cf->data[1] |= CAN_ERR_CRTL_TX_WARNING |
CAN_ERR_CRTL_RX_WARNING;
mc->pdev->dev.can.can_stats.error_warning++;
break;
default:
/* CAN_STATE_MAX (trick to handle other errors) */
cf->can_id |= CAN_ERR_CRTL;
cf->data[1] |= CAN_ERR_CRTL_RX_OVERFLOW;
mc->netdev->stats.rx_over_errors++;
mc->netdev->stats.rx_errors++;
new_state = mc->pdev->dev.can.state;
break;
}
mc->pdev->dev.can.state = new_state;
if (status_len & PCAN_USB_STATUSLEN_TIMESTAMP) {
struct skb_shared_hwtstamps *hwts = skb_hwtstamps(skb);
peak_usb_get_ts_time(&mc->pdev->time_ref, mc->ts16,
&hwts->hwtstamp);
}
mc->netdev->stats.rx_packets++;
mc->netdev->stats.rx_bytes += cf->can_dlc;
netif_rx(skb);
return 0;
}
/*
* decode non-data usb message
*/
static int pcan_usb_decode_status(struct pcan_usb_msg_context *mc,
u8 status_len)
{
u8 rec_len = status_len & PCAN_USB_STATUSLEN_DLC;
u8 f, n;
int err;
/* check whether function and number can be read */
if ((mc->ptr + 2) > mc->end)
return -EINVAL;
f = mc->ptr[PCAN_USB_CMD_FUNC];
n = mc->ptr[PCAN_USB_CMD_NUM];
mc->ptr += PCAN_USB_CMD_ARGS;
if (status_len & PCAN_USB_STATUSLEN_TIMESTAMP) {
int err = pcan_usb_decode_ts(mc, !mc->rec_idx);
if (err)
return err;
}
switch (f) {
case PCAN_USB_REC_ERROR:
err = pcan_usb_decode_error(mc, n, status_len);
if (err)
return err;
break;
case PCAN_USB_REC_ANALOG:
/* analog values (ignored) */
rec_len = 2;
break;
case PCAN_USB_REC_BUSLOAD:
/* bus load (ignored) */
rec_len = 1;
break;
case PCAN_USB_REC_TS:
/* only timestamp */
if (pcan_usb_update_ts(mc))
return -EINVAL;
break;
case PCAN_USB_REC_BUSEVT:
/* error frame/bus event */
if (n & PCAN_USB_ERROR_TXQFULL)
netdev_dbg(mc->netdev, "device Tx queue full)\n");
break;
default:
netdev_err(mc->netdev, "unexpected function %u\n", f);
break;
}
if ((mc->ptr + rec_len) > mc->end)
return -EINVAL;
mc->ptr += rec_len;
return 0;
}
/*
* decode data usb message
*/
static int pcan_usb_decode_data(struct pcan_usb_msg_context *mc, u8 status_len)
{
u8 rec_len = status_len & PCAN_USB_STATUSLEN_DLC;
struct sk_buff *skb;
struct can_frame *cf;
struct skb_shared_hwtstamps *hwts;
skb = alloc_can_skb(mc->netdev, &cf);
if (!skb)
return -ENOMEM;
if (status_len & PCAN_USB_STATUSLEN_EXT_ID) {
__le32 tmp32;
if ((mc->ptr + 4) > mc->end)
goto decode_failed;
memcpy(&tmp32, mc->ptr, 4);
mc->ptr += 4;
cf->can_id = (le32_to_cpu(tmp32) >> 3) | CAN_EFF_FLAG;
} else {
__le16 tmp16;
if ((mc->ptr + 2) > mc->end)
goto decode_failed;
memcpy(&tmp16, mc->ptr, 2);
mc->ptr += 2;
cf->can_id = le16_to_cpu(tmp16) >> 5;
}
cf->can_dlc = get_can_dlc(rec_len);
/* first data packet timestamp is a word */
if (pcan_usb_decode_ts(mc, !mc->rec_data_idx))
goto decode_failed;
/* read data */
memset(cf->data, 0x0, sizeof(cf->data));
if (status_len & PCAN_USB_STATUSLEN_RTR) {
cf->can_id |= CAN_RTR_FLAG;
} else {
if ((mc->ptr + rec_len) > mc->end)
goto decode_failed;
memcpy(cf->data, mc->ptr, cf->can_dlc);
mc->ptr += rec_len;
}
/* convert timestamp into kernel time */
hwts = skb_hwtstamps(skb);
peak_usb_get_ts_time(&mc->pdev->time_ref, mc->ts16, &hwts->hwtstamp);
/* update statistics */
mc->netdev->stats.rx_packets++;
mc->netdev->stats.rx_bytes += cf->can_dlc;
/* push the skb */
netif_rx(skb);
return 0;
decode_failed:
dev_kfree_skb(skb);
return -EINVAL;
}
/*
* process incoming message
*/
static int pcan_usb_decode_msg(struct peak_usb_device *dev, u8 *ibuf, u32 lbuf)
{
struct pcan_usb_msg_context mc = {
.rec_cnt = ibuf[1],
.ptr = ibuf + PCAN_USB_MSG_HEADER_LEN,
.end = ibuf + lbuf,
.netdev = dev->netdev,
.pdev = container_of(dev, struct pcan_usb, dev),
};
int err;
for (err = 0; mc.rec_idx < mc.rec_cnt && !err; mc.rec_idx++) {
u8 sl = *mc.ptr++;
/* handle status and error frames here */
if (sl & PCAN_USB_STATUSLEN_INTERNAL) {
err = pcan_usb_decode_status(&mc, sl);
/* handle normal can frames here */
} else {
err = pcan_usb_decode_data(&mc, sl);
mc.rec_data_idx++;
}
}
return err;
}
/*
* process any incoming buffer
*/
static int pcan_usb_decode_buf(struct peak_usb_device *dev, struct urb *urb)
{
int err = 0;
if (urb->actual_length > PCAN_USB_MSG_HEADER_LEN) {
err = pcan_usb_decode_msg(dev, urb->transfer_buffer,
urb->actual_length);
} else if (urb->actual_length > 0) {
netdev_err(dev->netdev, "usb message length error (%u)\n",
urb->actual_length);
err = -EINVAL;
}
return err;
}
/*
* process outgoing packet
*/
static int pcan_usb_encode_msg(struct peak_usb_device *dev, struct sk_buff *skb,
u8 *obuf, size_t *size)
{
struct net_device *netdev = dev->netdev;
struct net_device_stats *stats = &netdev->stats;
struct can_frame *cf = (struct can_frame *)skb->data;
u8 *pc;
obuf[0] = 2;
obuf[1] = 1;
pc = obuf + PCAN_USB_MSG_HEADER_LEN;
/* status/len byte */
*pc = cf->can_dlc;
if (cf->can_id & CAN_RTR_FLAG)
*pc |= PCAN_USB_STATUSLEN_RTR;
/* can id */
if (cf->can_id & CAN_EFF_FLAG) {
__le32 tmp32 = cpu_to_le32((cf->can_id & CAN_ERR_MASK) << 3);
*pc |= PCAN_USB_STATUSLEN_EXT_ID;
memcpy(++pc, &tmp32, 4);
pc += 4;
} else {
__le16 tmp16 = cpu_to_le16((cf->can_id & CAN_ERR_MASK) << 5);
memcpy(++pc, &tmp16, 2);
pc += 2;
}
/* can data */
if (!(cf->can_id & CAN_RTR_FLAG)) {
memcpy(pc, cf->data, cf->can_dlc);
pc += cf->can_dlc;
}
obuf[(*size)-1] = (u8)(stats->tx_packets & 0xff);
return 0;
}
/*
* start interface
*/
static int pcan_usb_start(struct peak_usb_device *dev)
{
struct pcan_usb *pdev = container_of(dev, struct pcan_usb, dev);
/* number of bits used in timestamps read from adapter struct */
peak_usb_init_time_ref(&pdev->time_ref, &pcan_usb);
/* if revision greater than 3, can put silent mode on/off */
if (dev->device_rev > 3) {
int err;
err = pcan_usb_set_silent(dev,
dev->can.ctrlmode & CAN_CTRLMODE_LISTENONLY);
if (err)
return err;
}
return pcan_usb_set_ext_vcc(dev, 0);
}
static int pcan_usb_init(struct peak_usb_device *dev)
{
struct pcan_usb *pdev = container_of(dev, struct pcan_usb, dev);
u32 serial_number;
int err;
/* initialize a timer needed to wait for hardware restart */
timer_setup(&pdev->restart_timer, pcan_usb_restart, 0);
/*
* explicit use of dev_xxx() instead of netdev_xxx() here:
* information displayed are related to the device itself, not
* to the canx netdevice.
*/
err = pcan_usb_get_serial(dev, &serial_number);
if (err) {
dev_err(dev->netdev->dev.parent,
"unable to read %s serial number (err %d)\n",
pcan_usb.name, err);
return err;
}
dev_info(dev->netdev->dev.parent,
"PEAK-System %s adapter hwrev %u serial %08X (%u channel)\n",
pcan_usb.name, dev->device_rev, serial_number,
pcan_usb.ctrl_count);
return 0;
}
/*
* probe function for new PCAN-USB usb interface
*/
static int pcan_usb_probe(struct usb_interface *intf)
{
struct usb_host_interface *if_desc;
int i;
if_desc = intf->altsetting;
/* check interface endpoint addresses */
for (i = 0; i < if_desc->desc.bNumEndpoints; i++) {
struct usb_endpoint_descriptor *ep = &if_desc->endpoint[i].desc;
switch (ep->bEndpointAddress) {
case PCAN_USB_EP_CMDOUT:
case PCAN_USB_EP_CMDIN:
case PCAN_USB_EP_MSGOUT:
case PCAN_USB_EP_MSGIN:
break;
default:
return -ENODEV;
}
}
return 0;
}
/*
* describe the PCAN-USB adapter
*/
static const struct can_bittiming_const pcan_usb_const = {
.name = "pcan_usb",
.tseg1_min = 1,
.tseg1_max = 16,
.tseg2_min = 1,
.tseg2_max = 8,
.sjw_max = 4,
.brp_min = 1,
.brp_max = 64,
.brp_inc = 1,
};
const struct peak_usb_adapter pcan_usb = {
.name = "PCAN-USB",
.device_id = PCAN_USB_PRODUCT_ID,
.ctrl_count = 1,
.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES | CAN_CTRLMODE_LISTENONLY,
.clock = {
.freq = PCAN_USB_CRYSTAL_HZ / 2 ,
},
.bittiming_const = &pcan_usb_const,
/* size of device private data */
.sizeof_dev_private = sizeof(struct pcan_usb),
/* timestamps usage */
.ts_used_bits = 16,
.ts_period = 24575, /* calibration period in ts. */
.us_per_ts_scale = PCAN_USB_TS_US_PER_TICK, /* us=(ts*scale) */
.us_per_ts_shift = PCAN_USB_TS_DIV_SHIFTER, /* >> shift */
/* give here messages in/out endpoints */
.ep_msg_in = PCAN_USB_EP_MSGIN,
.ep_msg_out = {PCAN_USB_EP_MSGOUT},
/* size of rx/tx usb buffers */
.rx_buffer_size = PCAN_USB_RX_BUFFER_SIZE,
.tx_buffer_size = PCAN_USB_TX_BUFFER_SIZE,
/* device callbacks */
.intf_probe = pcan_usb_probe,
.dev_init = pcan_usb_init,
.dev_set_bus = pcan_usb_write_mode,
.dev_set_bittiming = pcan_usb_set_bittiming,
.dev_get_device_id = pcan_usb_get_device_id,
.dev_decode_buf = pcan_usb_decode_buf,
.dev_encode_msg = pcan_usb_encode_msg,
.dev_start = pcan_usb_start,
.dev_restart_async = pcan_usb_restart_async,
};
|