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19#include <linux/module.h>
20#include <linux/kernel.h>
21#include <linux/slab.h>
22#include <linux/netdevice.h>
23#include <linux/if_arp.h>
24#include <linux/workqueue.h>
25#include <linux/can.h>
26#include <linux/can/dev.h>
27#include <linux/can/skb.h>
28#include <linux/can/netlink.h>
29#include <linux/can/led.h>
30#include <net/rtnetlink.h>
31
32#define MOD_DESC "CAN device driver interface"
33
34MODULE_DESCRIPTION(MOD_DESC);
35MODULE_LICENSE("GPL v2");
36MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
37
38
39
40static const u8 dlc2len[] = {0, 1, 2, 3, 4, 5, 6, 7,
41 8, 12, 16, 20, 24, 32, 48, 64};
42
43
44u8 can_dlc2len(u8 can_dlc)
45{
46 return dlc2len[can_dlc & 0x0F];
47}
48EXPORT_SYMBOL_GPL(can_dlc2len);
49
50static const u8 len2dlc[] = {0, 1, 2, 3, 4, 5, 6, 7, 8,
51 9, 9, 9, 9,
52 10, 10, 10, 10,
53 11, 11, 11, 11,
54 12, 12, 12, 12,
55 13, 13, 13, 13, 13, 13, 13, 13,
56 14, 14, 14, 14, 14, 14, 14, 14,
57 14, 14, 14, 14, 14, 14, 14, 14,
58 15, 15, 15, 15, 15, 15, 15, 15,
59 15, 15, 15, 15, 15, 15, 15, 15};
60
61
62u8 can_len2dlc(u8 len)
63{
64 if (unlikely(len > 64))
65 return 0xF;
66
67 return len2dlc[len];
68}
69EXPORT_SYMBOL_GPL(can_len2dlc);
70
71#ifdef CONFIG_CAN_CALC_BITTIMING
72#define CAN_CALC_MAX_ERROR 50
73#define CAN_CALC_SYNC_SEG 1
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88static int can_update_sample_point(const struct can_bittiming_const *btc,
89 unsigned int sample_point_nominal, unsigned int tseg,
90 unsigned int *tseg1_ptr, unsigned int *tseg2_ptr,
91 unsigned int *sample_point_error_ptr)
92{
93 unsigned int sample_point_error, best_sample_point_error = UINT_MAX;
94 unsigned int sample_point, best_sample_point = 0;
95 unsigned int tseg1, tseg2;
96 int i;
97
98 for (i = 0; i <= 1; i++) {
99 tseg2 = tseg + CAN_CALC_SYNC_SEG - (sample_point_nominal * (tseg + CAN_CALC_SYNC_SEG)) / 1000 - i;
100 tseg2 = clamp(tseg2, btc->tseg2_min, btc->tseg2_max);
101 tseg1 = tseg - tseg2;
102 if (tseg1 > btc->tseg1_max) {
103 tseg1 = btc->tseg1_max;
104 tseg2 = tseg - tseg1;
105 }
106
107 sample_point = 1000 * (tseg + CAN_CALC_SYNC_SEG - tseg2) / (tseg + CAN_CALC_SYNC_SEG);
108 sample_point_error = abs(sample_point_nominal - sample_point);
109
110 if ((sample_point <= sample_point_nominal) && (sample_point_error < best_sample_point_error)) {
111 best_sample_point = sample_point;
112 best_sample_point_error = sample_point_error;
113 *tseg1_ptr = tseg1;
114 *tseg2_ptr = tseg2;
115 }
116 }
117
118 if (sample_point_error_ptr)
119 *sample_point_error_ptr = best_sample_point_error;
120
121 return best_sample_point;
122}
123
124static int can_calc_bittiming(struct net_device *dev, struct can_bittiming *bt,
125 const struct can_bittiming_const *btc)
126{
127 struct can_priv *priv = netdev_priv(dev);
128 unsigned int bitrate;
129 unsigned int bitrate_error;
130 unsigned int best_bitrate_error = UINT_MAX;
131 unsigned int sample_point_error;
132 unsigned int best_sample_point_error = UINT_MAX;
133 unsigned int sample_point_nominal;
134 unsigned int best_tseg = 0;
135 unsigned int best_brp = 0;
136 unsigned int brp, tsegall, tseg, tseg1 = 0, tseg2 = 0;
137 u64 v64;
138
139
140 if (bt->sample_point) {
141 sample_point_nominal = bt->sample_point;
142 } else {
143 if (bt->bitrate > 800000)
144 sample_point_nominal = 750;
145 else if (bt->bitrate > 500000)
146 sample_point_nominal = 800;
147 else
148 sample_point_nominal = 875;
149 }
150
151
152 for (tseg = (btc->tseg1_max + btc->tseg2_max) * 2 + 1;
153 tseg >= (btc->tseg1_min + btc->tseg2_min) * 2; tseg--) {
154 tsegall = CAN_CALC_SYNC_SEG + tseg / 2;
155
156
157 brp = priv->clock.freq / (tsegall * bt->bitrate) + tseg % 2;
158
159
160 brp = (brp / btc->brp_inc) * btc->brp_inc;
161 if ((brp < btc->brp_min) || (brp > btc->brp_max))
162 continue;
163
164 bitrate = priv->clock.freq / (brp * tsegall);
165 bitrate_error = abs(bt->bitrate - bitrate);
166
167
168 if (bitrate_error > best_bitrate_error)
169 continue;
170
171
172 if (bitrate_error < best_bitrate_error)
173 best_sample_point_error = UINT_MAX;
174
175 can_update_sample_point(btc, sample_point_nominal, tseg / 2, &tseg1, &tseg2, &sample_point_error);
176 if (sample_point_error > best_sample_point_error)
177 continue;
178
179 best_sample_point_error = sample_point_error;
180 best_bitrate_error = bitrate_error;
181 best_tseg = tseg / 2;
182 best_brp = brp;
183
184 if (bitrate_error == 0 && sample_point_error == 0)
185 break;
186 }
187
188 if (best_bitrate_error) {
189
190 v64 = (u64)best_bitrate_error * 1000;
191 do_div(v64, bt->bitrate);
192 bitrate_error = (u32)v64;
193 if (bitrate_error > CAN_CALC_MAX_ERROR) {
194 netdev_err(dev,
195 "bitrate error %d.%d%% too high\n",
196 bitrate_error / 10, bitrate_error % 10);
197 return -EDOM;
198 }
199 netdev_warn(dev, "bitrate error %d.%d%%\n",
200 bitrate_error / 10, bitrate_error % 10);
201 }
202
203
204 bt->sample_point = can_update_sample_point(btc, sample_point_nominal, best_tseg,
205 &tseg1, &tseg2, NULL);
206
207 v64 = (u64)best_brp * 1000 * 1000 * 1000;
208 do_div(v64, priv->clock.freq);
209 bt->tq = (u32)v64;
210 bt->prop_seg = tseg1 / 2;
211 bt->phase_seg1 = tseg1 - bt->prop_seg;
212 bt->phase_seg2 = tseg2;
213
214
215 if (!bt->sjw || !btc->sjw_max) {
216 bt->sjw = 1;
217 } else {
218
219 if (bt->sjw > btc->sjw_max)
220 bt->sjw = btc->sjw_max;
221
222 if (tseg2 < bt->sjw)
223 bt->sjw = tseg2;
224 }
225
226 bt->brp = best_brp;
227
228
229 bt->bitrate = priv->clock.freq / (bt->brp * (CAN_CALC_SYNC_SEG + tseg1 + tseg2));
230
231 return 0;
232}
233#else
234static int can_calc_bittiming(struct net_device *dev, struct can_bittiming *bt,
235 const struct can_bittiming_const *btc)
236{
237 netdev_err(dev, "bit-timing calculation not available\n");
238 return -EINVAL;
239}
240#endif
241
242
243
244
245
246
247
248static int can_fixup_bittiming(struct net_device *dev, struct can_bittiming *bt,
249 const struct can_bittiming_const *btc)
250{
251 struct can_priv *priv = netdev_priv(dev);
252 int tseg1, alltseg;
253 u64 brp64;
254
255 tseg1 = bt->prop_seg + bt->phase_seg1;
256 if (!bt->sjw)
257 bt->sjw = 1;
258 if (bt->sjw > btc->sjw_max ||
259 tseg1 < btc->tseg1_min || tseg1 > btc->tseg1_max ||
260 bt->phase_seg2 < btc->tseg2_min || bt->phase_seg2 > btc->tseg2_max)
261 return -ERANGE;
262
263 brp64 = (u64)priv->clock.freq * (u64)bt->tq;
264 if (btc->brp_inc > 1)
265 do_div(brp64, btc->brp_inc);
266 brp64 += 500000000UL - 1;
267 do_div(brp64, 1000000000UL);
268 if (btc->brp_inc > 1)
269 brp64 *= btc->brp_inc;
270 bt->brp = (u32)brp64;
271
272 if (bt->brp < btc->brp_min || bt->brp > btc->brp_max)
273 return -EINVAL;
274
275 alltseg = bt->prop_seg + bt->phase_seg1 + bt->phase_seg2 + 1;
276 bt->bitrate = priv->clock.freq / (bt->brp * alltseg);
277 bt->sample_point = ((tseg1 + 1) * 1000) / alltseg;
278
279 return 0;
280}
281
282
283static int can_validate_bitrate(struct net_device *dev, struct can_bittiming *bt,
284 const u32 *bitrate_const,
285 const unsigned int bitrate_const_cnt)
286{
287 struct can_priv *priv = netdev_priv(dev);
288 unsigned int i;
289
290 for (i = 0; i < bitrate_const_cnt; i++) {
291 if (bt->bitrate == bitrate_const[i])
292 break;
293 }
294
295 if (i >= priv->bitrate_const_cnt)
296 return -EINVAL;
297
298 return 0;
299}
300
301static int can_get_bittiming(struct net_device *dev, struct can_bittiming *bt,
302 const struct can_bittiming_const *btc,
303 const u32 *bitrate_const,
304 const unsigned int bitrate_const_cnt)
305{
306 int err;
307
308
309
310
311
312
313
314 if (!bt->tq && bt->bitrate && btc)
315 err = can_calc_bittiming(dev, bt, btc);
316 else if (bt->tq && !bt->bitrate && btc)
317 err = can_fixup_bittiming(dev, bt, btc);
318 else if (!bt->tq && bt->bitrate && bitrate_const)
319 err = can_validate_bitrate(dev, bt, bitrate_const,
320 bitrate_const_cnt);
321 else
322 err = -EINVAL;
323
324 return err;
325}
326
327static void can_update_state_error_stats(struct net_device *dev,
328 enum can_state new_state)
329{
330 struct can_priv *priv = netdev_priv(dev);
331
332 if (new_state <= priv->state)
333 return;
334
335 switch (new_state) {
336 case CAN_STATE_ERROR_WARNING:
337 priv->can_stats.error_warning++;
338 break;
339 case CAN_STATE_ERROR_PASSIVE:
340 priv->can_stats.error_passive++;
341 break;
342 case CAN_STATE_BUS_OFF:
343 priv->can_stats.bus_off++;
344 break;
345 default:
346 break;
347 }
348}
349
350static int can_tx_state_to_frame(struct net_device *dev, enum can_state state)
351{
352 switch (state) {
353 case CAN_STATE_ERROR_ACTIVE:
354 return CAN_ERR_CRTL_ACTIVE;
355 case CAN_STATE_ERROR_WARNING:
356 return CAN_ERR_CRTL_TX_WARNING;
357 case CAN_STATE_ERROR_PASSIVE:
358 return CAN_ERR_CRTL_TX_PASSIVE;
359 default:
360 return 0;
361 }
362}
363
364static int can_rx_state_to_frame(struct net_device *dev, enum can_state state)
365{
366 switch (state) {
367 case CAN_STATE_ERROR_ACTIVE:
368 return CAN_ERR_CRTL_ACTIVE;
369 case CAN_STATE_ERROR_WARNING:
370 return CAN_ERR_CRTL_RX_WARNING;
371 case CAN_STATE_ERROR_PASSIVE:
372 return CAN_ERR_CRTL_RX_PASSIVE;
373 default:
374 return 0;
375 }
376}
377
378void can_change_state(struct net_device *dev, struct can_frame *cf,
379 enum can_state tx_state, enum can_state rx_state)
380{
381 struct can_priv *priv = netdev_priv(dev);
382 enum can_state new_state = max(tx_state, rx_state);
383
384 if (unlikely(new_state == priv->state)) {
385 netdev_warn(dev, "%s: oops, state did not change", __func__);
386 return;
387 }
388
389 netdev_dbg(dev, "New error state: %d\n", new_state);
390
391 can_update_state_error_stats(dev, new_state);
392 priv->state = new_state;
393
394 if (!cf)
395 return;
396
397 if (unlikely(new_state == CAN_STATE_BUS_OFF)) {
398 cf->can_id |= CAN_ERR_BUSOFF;
399 return;
400 }
401
402 cf->can_id |= CAN_ERR_CRTL;
403 cf->data[1] |= tx_state >= rx_state ?
404 can_tx_state_to_frame(dev, tx_state) : 0;
405 cf->data[1] |= tx_state <= rx_state ?
406 can_rx_state_to_frame(dev, rx_state) : 0;
407}
408EXPORT_SYMBOL_GPL(can_change_state);
409
410
411
412
413
414
415
416
417
418
419
420static void can_flush_echo_skb(struct net_device *dev)
421{
422 struct can_priv *priv = netdev_priv(dev);
423 struct net_device_stats *stats = &dev->stats;
424 int i;
425
426 for (i = 0; i < priv->echo_skb_max; i++) {
427 if (priv->echo_skb[i]) {
428 kfree_skb(priv->echo_skb[i]);
429 priv->echo_skb[i] = NULL;
430 stats->tx_dropped++;
431 stats->tx_aborted_errors++;
432 }
433 }
434}
435
436
437
438
439
440
441
442
443void can_put_echo_skb(struct sk_buff *skb, struct net_device *dev,
444 unsigned int idx)
445{
446 struct can_priv *priv = netdev_priv(dev);
447
448 BUG_ON(idx >= priv->echo_skb_max);
449
450
451 if (!(dev->flags & IFF_ECHO) || skb->pkt_type != PACKET_LOOPBACK ||
452 (skb->protocol != htons(ETH_P_CAN) &&
453 skb->protocol != htons(ETH_P_CANFD))) {
454 kfree_skb(skb);
455 return;
456 }
457
458 if (!priv->echo_skb[idx]) {
459
460 skb = can_create_echo_skb(skb);
461 if (!skb)
462 return;
463
464
465 skb->pkt_type = PACKET_BROADCAST;
466 skb->ip_summed = CHECKSUM_UNNECESSARY;
467 skb->dev = dev;
468
469
470 priv->echo_skb[idx] = skb;
471 } else {
472
473 netdev_err(dev, "%s: BUG! echo_skb is occupied!\n", __func__);
474 kfree_skb(skb);
475 }
476}
477EXPORT_SYMBOL_GPL(can_put_echo_skb);
478
479
480
481
482
483
484
485
486unsigned int can_get_echo_skb(struct net_device *dev, unsigned int idx)
487{
488 struct can_priv *priv = netdev_priv(dev);
489
490 BUG_ON(idx >= priv->echo_skb_max);
491
492 if (priv->echo_skb[idx]) {
493 struct sk_buff *skb = priv->echo_skb[idx];
494 struct can_frame *cf = (struct can_frame *)skb->data;
495 u8 dlc = cf->can_dlc;
496
497 netif_rx(priv->echo_skb[idx]);
498 priv->echo_skb[idx] = NULL;
499
500 return dlc;
501 }
502
503 return 0;
504}
505EXPORT_SYMBOL_GPL(can_get_echo_skb);
506
507
508
509
510
511
512void can_free_echo_skb(struct net_device *dev, unsigned int idx)
513{
514 struct can_priv *priv = netdev_priv(dev);
515
516 BUG_ON(idx >= priv->echo_skb_max);
517
518 if (priv->echo_skb[idx]) {
519 dev_kfree_skb_any(priv->echo_skb[idx]);
520 priv->echo_skb[idx] = NULL;
521 }
522}
523EXPORT_SYMBOL_GPL(can_free_echo_skb);
524
525
526
527
528static void can_restart(struct net_device *dev)
529{
530 struct can_priv *priv = netdev_priv(dev);
531 struct net_device_stats *stats = &dev->stats;
532 struct sk_buff *skb;
533 struct can_frame *cf;
534 int err;
535
536 BUG_ON(netif_carrier_ok(dev));
537
538
539
540
541
542 can_flush_echo_skb(dev);
543
544
545 skb = alloc_can_err_skb(dev, &cf);
546 if (skb == NULL) {
547 err = -ENOMEM;
548 goto restart;
549 }
550 cf->can_id |= CAN_ERR_RESTARTED;
551
552 netif_rx(skb);
553
554 stats->rx_packets++;
555 stats->rx_bytes += cf->can_dlc;
556
557restart:
558 netdev_dbg(dev, "restarted\n");
559 priv->can_stats.restarts++;
560
561
562 err = priv->do_set_mode(dev, CAN_MODE_START);
563
564 netif_carrier_on(dev);
565 if (err)
566 netdev_err(dev, "Error %d during restart", err);
567}
568
569static void can_restart_work(struct work_struct *work)
570{
571 struct delayed_work *dwork = to_delayed_work(work);
572 struct can_priv *priv = container_of(dwork, struct can_priv, restart_work);
573
574 can_restart(priv->dev);
575}
576
577int can_restart_now(struct net_device *dev)
578{
579 struct can_priv *priv = netdev_priv(dev);
580
581
582
583
584
585 if (priv->restart_ms)
586 return -EINVAL;
587 if (priv->state != CAN_STATE_BUS_OFF)
588 return -EBUSY;
589
590 cancel_delayed_work_sync(&priv->restart_work);
591 can_restart(dev);
592
593 return 0;
594}
595
596
597
598
599
600
601
602
603void can_bus_off(struct net_device *dev)
604{
605 struct can_priv *priv = netdev_priv(dev);
606
607 netdev_dbg(dev, "bus-off\n");
608
609 netif_carrier_off(dev);
610
611 if (priv->restart_ms)
612 schedule_delayed_work(&priv->restart_work,
613 msecs_to_jiffies(priv->restart_ms));
614}
615EXPORT_SYMBOL_GPL(can_bus_off);
616
617static void can_setup(struct net_device *dev)
618{
619 dev->type = ARPHRD_CAN;
620 dev->mtu = CAN_MTU;
621 dev->hard_header_len = 0;
622 dev->addr_len = 0;
623 dev->tx_queue_len = 10;
624
625
626 dev->flags = IFF_NOARP;
627 dev->features = NETIF_F_HW_CSUM;
628}
629
630struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf)
631{
632 struct sk_buff *skb;
633
634 skb = netdev_alloc_skb(dev, sizeof(struct can_skb_priv) +
635 sizeof(struct can_frame));
636 if (unlikely(!skb))
637 return NULL;
638
639 skb->protocol = htons(ETH_P_CAN);
640 skb->pkt_type = PACKET_BROADCAST;
641 skb->ip_summed = CHECKSUM_UNNECESSARY;
642
643 skb_reset_mac_header(skb);
644 skb_reset_network_header(skb);
645 skb_reset_transport_header(skb);
646
647 can_skb_reserve(skb);
648 can_skb_prv(skb)->ifindex = dev->ifindex;
649 can_skb_prv(skb)->skbcnt = 0;
650
651 *cf = skb_put(skb, sizeof(struct can_frame));
652 memset(*cf, 0, sizeof(struct can_frame));
653
654 return skb;
655}
656EXPORT_SYMBOL_GPL(alloc_can_skb);
657
658struct sk_buff *alloc_canfd_skb(struct net_device *dev,
659 struct canfd_frame **cfd)
660{
661 struct sk_buff *skb;
662
663 skb = netdev_alloc_skb(dev, sizeof(struct can_skb_priv) +
664 sizeof(struct canfd_frame));
665 if (unlikely(!skb))
666 return NULL;
667
668 skb->protocol = htons(ETH_P_CANFD);
669 skb->pkt_type = PACKET_BROADCAST;
670 skb->ip_summed = CHECKSUM_UNNECESSARY;
671
672 skb_reset_mac_header(skb);
673 skb_reset_network_header(skb);
674 skb_reset_transport_header(skb);
675
676 can_skb_reserve(skb);
677 can_skb_prv(skb)->ifindex = dev->ifindex;
678 can_skb_prv(skb)->skbcnt = 0;
679
680 *cfd = skb_put(skb, sizeof(struct canfd_frame));
681 memset(*cfd, 0, sizeof(struct canfd_frame));
682
683 return skb;
684}
685EXPORT_SYMBOL_GPL(alloc_canfd_skb);
686
687struct sk_buff *alloc_can_err_skb(struct net_device *dev, struct can_frame **cf)
688{
689 struct sk_buff *skb;
690
691 skb = alloc_can_skb(dev, cf);
692 if (unlikely(!skb))
693 return NULL;
694
695 (*cf)->can_id = CAN_ERR_FLAG;
696 (*cf)->can_dlc = CAN_ERR_DLC;
697
698 return skb;
699}
700EXPORT_SYMBOL_GPL(alloc_can_err_skb);
701
702
703
704
705struct net_device *alloc_candev(int sizeof_priv, unsigned int echo_skb_max)
706{
707 struct net_device *dev;
708 struct can_priv *priv;
709 int size;
710
711 if (echo_skb_max)
712 size = ALIGN(sizeof_priv, sizeof(struct sk_buff *)) +
713 echo_skb_max * sizeof(struct sk_buff *);
714 else
715 size = sizeof_priv;
716
717 dev = alloc_netdev(size, "can%d", NET_NAME_UNKNOWN, can_setup);
718 if (!dev)
719 return NULL;
720
721 priv = netdev_priv(dev);
722 priv->dev = dev;
723
724 if (echo_skb_max) {
725 priv->echo_skb_max = echo_skb_max;
726 priv->echo_skb = (void *)priv +
727 ALIGN(sizeof_priv, sizeof(struct sk_buff *));
728 }
729
730 priv->state = CAN_STATE_STOPPED;
731
732 INIT_DELAYED_WORK(&priv->restart_work, can_restart_work);
733
734 return dev;
735}
736EXPORT_SYMBOL_GPL(alloc_candev);
737
738
739
740
741void free_candev(struct net_device *dev)
742{
743 free_netdev(dev);
744}
745EXPORT_SYMBOL_GPL(free_candev);
746
747
748
749
750int can_change_mtu(struct net_device *dev, int new_mtu)
751{
752 struct can_priv *priv = netdev_priv(dev);
753
754
755 if (dev->flags & IFF_UP)
756 return -EBUSY;
757
758
759 switch (new_mtu) {
760 case CAN_MTU:
761
762 if (priv->ctrlmode_static & CAN_CTRLMODE_FD)
763 return -EINVAL;
764
765 priv->ctrlmode &= ~CAN_CTRLMODE_FD;
766 break;
767
768 case CANFD_MTU:
769
770 if (!(priv->ctrlmode_supported & CAN_CTRLMODE_FD) &&
771 !(priv->ctrlmode_static & CAN_CTRLMODE_FD))
772 return -EINVAL;
773
774 priv->ctrlmode |= CAN_CTRLMODE_FD;
775 break;
776
777 default:
778 return -EINVAL;
779 }
780
781 dev->mtu = new_mtu;
782 return 0;
783}
784EXPORT_SYMBOL_GPL(can_change_mtu);
785
786
787
788
789
790
791
792int open_candev(struct net_device *dev)
793{
794 struct can_priv *priv = netdev_priv(dev);
795
796 if (!priv->bittiming.bitrate) {
797 netdev_err(dev, "bit-timing not yet defined\n");
798 return -EINVAL;
799 }
800
801
802 if ((priv->ctrlmode & CAN_CTRLMODE_FD) &&
803 (!priv->data_bittiming.bitrate ||
804 (priv->data_bittiming.bitrate < priv->bittiming.bitrate))) {
805 netdev_err(dev, "incorrect/missing data bit-timing\n");
806 return -EINVAL;
807 }
808
809
810 if (!netif_carrier_ok(dev))
811 netif_carrier_on(dev);
812
813 return 0;
814}
815EXPORT_SYMBOL_GPL(open_candev);
816
817
818
819
820
821
822
823void close_candev(struct net_device *dev)
824{
825 struct can_priv *priv = netdev_priv(dev);
826
827 cancel_delayed_work_sync(&priv->restart_work);
828 can_flush_echo_skb(dev);
829}
830EXPORT_SYMBOL_GPL(close_candev);
831
832
833
834
835static const struct nla_policy can_policy[IFLA_CAN_MAX + 1] = {
836 [IFLA_CAN_STATE] = { .type = NLA_U32 },
837 [IFLA_CAN_CTRLMODE] = { .len = sizeof(struct can_ctrlmode) },
838 [IFLA_CAN_RESTART_MS] = { .type = NLA_U32 },
839 [IFLA_CAN_RESTART] = { .type = NLA_U32 },
840 [IFLA_CAN_BITTIMING] = { .len = sizeof(struct can_bittiming) },
841 [IFLA_CAN_BITTIMING_CONST]
842 = { .len = sizeof(struct can_bittiming_const) },
843 [IFLA_CAN_CLOCK] = { .len = sizeof(struct can_clock) },
844 [IFLA_CAN_BERR_COUNTER] = { .len = sizeof(struct can_berr_counter) },
845 [IFLA_CAN_DATA_BITTIMING]
846 = { .len = sizeof(struct can_bittiming) },
847 [IFLA_CAN_DATA_BITTIMING_CONST]
848 = { .len = sizeof(struct can_bittiming_const) },
849};
850
851static int can_validate(struct nlattr *tb[], struct nlattr *data[],
852 struct netlink_ext_ack *extack)
853{
854 bool is_can_fd = false;
855
856
857
858
859
860
861
862 if (!data)
863 return 0;
864
865 if (data[IFLA_CAN_CTRLMODE]) {
866 struct can_ctrlmode *cm = nla_data(data[IFLA_CAN_CTRLMODE]);
867
868 is_can_fd = cm->flags & cm->mask & CAN_CTRLMODE_FD;
869 }
870
871 if (is_can_fd) {
872 if (!data[IFLA_CAN_BITTIMING] || !data[IFLA_CAN_DATA_BITTIMING])
873 return -EOPNOTSUPP;
874 }
875
876 if (data[IFLA_CAN_DATA_BITTIMING]) {
877 if (!is_can_fd || !data[IFLA_CAN_BITTIMING])
878 return -EOPNOTSUPP;
879 }
880
881 return 0;
882}
883
884static int can_changelink(struct net_device *dev, struct nlattr *tb[],
885 struct nlattr *data[],
886 struct netlink_ext_ack *extack)
887{
888 struct can_priv *priv = netdev_priv(dev);
889 int err;
890
891
892 ASSERT_RTNL();
893
894 if (data[IFLA_CAN_BITTIMING]) {
895 struct can_bittiming bt;
896
897
898 if (dev->flags & IFF_UP)
899 return -EBUSY;
900
901
902
903
904
905
906 if (!priv->bittiming_const && !priv->do_set_bittiming)
907 return -EOPNOTSUPP;
908
909 memcpy(&bt, nla_data(data[IFLA_CAN_BITTIMING]), sizeof(bt));
910 err = can_get_bittiming(dev, &bt,
911 priv->bittiming_const,
912 priv->bitrate_const,
913 priv->bitrate_const_cnt);
914 if (err)
915 return err;
916 memcpy(&priv->bittiming, &bt, sizeof(bt));
917
918 if (priv->do_set_bittiming) {
919
920 err = priv->do_set_bittiming(dev);
921 if (err)
922 return err;
923 }
924 }
925
926 if (data[IFLA_CAN_CTRLMODE]) {
927 struct can_ctrlmode *cm;
928 u32 ctrlstatic;
929 u32 maskedflags;
930
931
932 if (dev->flags & IFF_UP)
933 return -EBUSY;
934 cm = nla_data(data[IFLA_CAN_CTRLMODE]);
935 ctrlstatic = priv->ctrlmode_static;
936 maskedflags = cm->flags & cm->mask;
937
938
939 if (cm->mask & ~(priv->ctrlmode_supported | ctrlstatic))
940 return -EOPNOTSUPP;
941
942
943 if (!(maskedflags & CAN_CTRLMODE_FD))
944 ctrlstatic &= ~CAN_CTRLMODE_FD_NON_ISO;
945
946
947 if ((maskedflags & ctrlstatic) != ctrlstatic)
948 return -EOPNOTSUPP;
949
950
951 priv->ctrlmode &= ~cm->mask;
952 priv->ctrlmode |= maskedflags;
953
954
955 if (priv->ctrlmode & CAN_CTRLMODE_FD)
956 dev->mtu = CANFD_MTU;
957 else
958 dev->mtu = CAN_MTU;
959 }
960
961 if (data[IFLA_CAN_RESTART_MS]) {
962
963 if (dev->flags & IFF_UP)
964 return -EBUSY;
965 priv->restart_ms = nla_get_u32(data[IFLA_CAN_RESTART_MS]);
966 }
967
968 if (data[IFLA_CAN_RESTART]) {
969
970 if (!(dev->flags & IFF_UP))
971 return -EINVAL;
972 err = can_restart_now(dev);
973 if (err)
974 return err;
975 }
976
977 if (data[IFLA_CAN_DATA_BITTIMING]) {
978 struct can_bittiming dbt;
979
980
981 if (dev->flags & IFF_UP)
982 return -EBUSY;
983
984
985
986
987
988
989 if (!priv->data_bittiming_const && !priv->do_set_data_bittiming)
990 return -EOPNOTSUPP;
991
992 memcpy(&dbt, nla_data(data[IFLA_CAN_DATA_BITTIMING]),
993 sizeof(dbt));
994 err = can_get_bittiming(dev, &dbt,
995 priv->data_bittiming_const,
996 priv->data_bitrate_const,
997 priv->data_bitrate_const_cnt);
998 if (err)
999 return err;
1000 memcpy(&priv->data_bittiming, &dbt, sizeof(dbt));
1001
1002 if (priv->do_set_data_bittiming) {
1003
1004 err = priv->do_set_data_bittiming(dev);
1005 if (err)
1006 return err;
1007 }
1008 }
1009
1010 if (data[IFLA_CAN_TERMINATION]) {
1011 const u16 termval = nla_get_u16(data[IFLA_CAN_TERMINATION]);
1012 const unsigned int num_term = priv->termination_const_cnt;
1013 unsigned int i;
1014
1015 if (!priv->do_set_termination)
1016 return -EOPNOTSUPP;
1017
1018
1019 for (i = 0; i < num_term; i++) {
1020 if (termval == priv->termination_const[i])
1021 break;
1022 }
1023 if (i >= num_term)
1024 return -EINVAL;
1025
1026
1027 err = priv->do_set_termination(dev, termval);
1028 if (err)
1029 return err;
1030
1031 priv->termination = termval;
1032 }
1033
1034 return 0;
1035}
1036
1037static size_t can_get_size(const struct net_device *dev)
1038{
1039 struct can_priv *priv = netdev_priv(dev);
1040 size_t size = 0;
1041
1042 if (priv->bittiming.bitrate)
1043 size += nla_total_size(sizeof(struct can_bittiming));
1044 if (priv->bittiming_const)
1045 size += nla_total_size(sizeof(struct can_bittiming_const));
1046 size += nla_total_size(sizeof(struct can_clock));
1047 size += nla_total_size(sizeof(u32));
1048 size += nla_total_size(sizeof(struct can_ctrlmode));
1049 size += nla_total_size(sizeof(u32));
1050 if (priv->do_get_berr_counter)
1051 size += nla_total_size(sizeof(struct can_berr_counter));
1052 if (priv->data_bittiming.bitrate)
1053 size += nla_total_size(sizeof(struct can_bittiming));
1054 if (priv->data_bittiming_const)
1055 size += nla_total_size(sizeof(struct can_bittiming_const));
1056 if (priv->termination_const) {
1057 size += nla_total_size(sizeof(priv->termination));
1058 size += nla_total_size(sizeof(*priv->termination_const) *
1059 priv->termination_const_cnt);
1060 }
1061 if (priv->bitrate_const)
1062 size += nla_total_size(sizeof(*priv->bitrate_const) *
1063 priv->bitrate_const_cnt);
1064 if (priv->data_bitrate_const)
1065 size += nla_total_size(sizeof(*priv->data_bitrate_const) *
1066 priv->data_bitrate_const_cnt);
1067
1068 return size;
1069}
1070
1071static int can_fill_info(struct sk_buff *skb, const struct net_device *dev)
1072{
1073 struct can_priv *priv = netdev_priv(dev);
1074 struct can_ctrlmode cm = {.flags = priv->ctrlmode};
1075 struct can_berr_counter bec;
1076 enum can_state state = priv->state;
1077
1078 if (priv->do_get_state)
1079 priv->do_get_state(dev, &state);
1080
1081 if ((priv->bittiming.bitrate &&
1082 nla_put(skb, IFLA_CAN_BITTIMING,
1083 sizeof(priv->bittiming), &priv->bittiming)) ||
1084
1085 (priv->bittiming_const &&
1086 nla_put(skb, IFLA_CAN_BITTIMING_CONST,
1087 sizeof(*priv->bittiming_const), priv->bittiming_const)) ||
1088
1089 nla_put(skb, IFLA_CAN_CLOCK, sizeof(priv->clock), &priv->clock) ||
1090 nla_put_u32(skb, IFLA_CAN_STATE, state) ||
1091 nla_put(skb, IFLA_CAN_CTRLMODE, sizeof(cm), &cm) ||
1092 nla_put_u32(skb, IFLA_CAN_RESTART_MS, priv->restart_ms) ||
1093
1094 (priv->do_get_berr_counter &&
1095 !priv->do_get_berr_counter(dev, &bec) &&
1096 nla_put(skb, IFLA_CAN_BERR_COUNTER, sizeof(bec), &bec)) ||
1097
1098 (priv->data_bittiming.bitrate &&
1099 nla_put(skb, IFLA_CAN_DATA_BITTIMING,
1100 sizeof(priv->data_bittiming), &priv->data_bittiming)) ||
1101
1102 (priv->data_bittiming_const &&
1103 nla_put(skb, IFLA_CAN_DATA_BITTIMING_CONST,
1104 sizeof(*priv->data_bittiming_const),
1105 priv->data_bittiming_const)) ||
1106
1107 (priv->termination_const &&
1108 (nla_put_u16(skb, IFLA_CAN_TERMINATION, priv->termination) ||
1109 nla_put(skb, IFLA_CAN_TERMINATION_CONST,
1110 sizeof(*priv->termination_const) *
1111 priv->termination_const_cnt,
1112 priv->termination_const))) ||
1113
1114 (priv->bitrate_const &&
1115 nla_put(skb, IFLA_CAN_BITRATE_CONST,
1116 sizeof(*priv->bitrate_const) *
1117 priv->bitrate_const_cnt,
1118 priv->bitrate_const)) ||
1119
1120 (priv->data_bitrate_const &&
1121 nla_put(skb, IFLA_CAN_DATA_BITRATE_CONST,
1122 sizeof(*priv->data_bitrate_const) *
1123 priv->data_bitrate_const_cnt,
1124 priv->data_bitrate_const))
1125 )
1126
1127 return -EMSGSIZE;
1128
1129 return 0;
1130}
1131
1132static size_t can_get_xstats_size(const struct net_device *dev)
1133{
1134 return sizeof(struct can_device_stats);
1135}
1136
1137static int can_fill_xstats(struct sk_buff *skb, const struct net_device *dev)
1138{
1139 struct can_priv *priv = netdev_priv(dev);
1140
1141 if (nla_put(skb, IFLA_INFO_XSTATS,
1142 sizeof(priv->can_stats), &priv->can_stats))
1143 goto nla_put_failure;
1144 return 0;
1145
1146nla_put_failure:
1147 return -EMSGSIZE;
1148}
1149
1150static int can_newlink(struct net *src_net, struct net_device *dev,
1151 struct nlattr *tb[], struct nlattr *data[],
1152 struct netlink_ext_ack *extack)
1153{
1154 return -EOPNOTSUPP;
1155}
1156
1157static void can_dellink(struct net_device *dev, struct list_head *head)
1158{
1159 return;
1160}
1161
1162static struct rtnl_link_ops can_link_ops __read_mostly = {
1163 .kind = "can",
1164 .maxtype = IFLA_CAN_MAX,
1165 .policy = can_policy,
1166 .setup = can_setup,
1167 .validate = can_validate,
1168 .newlink = can_newlink,
1169 .changelink = can_changelink,
1170 .dellink = can_dellink,
1171 .get_size = can_get_size,
1172 .fill_info = can_fill_info,
1173 .get_xstats_size = can_get_xstats_size,
1174 .fill_xstats = can_fill_xstats,
1175};
1176
1177
1178
1179
1180int register_candev(struct net_device *dev)
1181{
1182 struct can_priv *priv = netdev_priv(dev);
1183
1184
1185
1186
1187
1188 if ((!priv->termination_const != !priv->termination_const_cnt) ||
1189 (!priv->termination_const != !priv->do_set_termination))
1190 return -EINVAL;
1191
1192 if (!priv->bitrate_const != !priv->bitrate_const_cnt)
1193 return -EINVAL;
1194
1195 if (!priv->data_bitrate_const != !priv->data_bitrate_const_cnt)
1196 return -EINVAL;
1197
1198 dev->rtnl_link_ops = &can_link_ops;
1199 return register_netdev(dev);
1200}
1201EXPORT_SYMBOL_GPL(register_candev);
1202
1203
1204
1205
1206void unregister_candev(struct net_device *dev)
1207{
1208 unregister_netdev(dev);
1209}
1210EXPORT_SYMBOL_GPL(unregister_candev);
1211
1212
1213
1214
1215
1216struct can_priv *safe_candev_priv(struct net_device *dev)
1217{
1218 if ((dev->type != ARPHRD_CAN) || (dev->rtnl_link_ops != &can_link_ops))
1219 return NULL;
1220
1221 return netdev_priv(dev);
1222}
1223EXPORT_SYMBOL_GPL(safe_candev_priv);
1224
1225static __init int can_dev_init(void)
1226{
1227 int err;
1228
1229 can_led_notifier_init();
1230
1231 err = rtnl_link_register(&can_link_ops);
1232 if (!err)
1233 printk(KERN_INFO MOD_DESC "\n");
1234
1235 return err;
1236}
1237module_init(can_dev_init);
1238
1239static __exit void can_dev_exit(void)
1240{
1241 rtnl_link_unregister(&can_link_ops);
1242
1243 can_led_notifier_exit();
1244}
1245module_exit(can_dev_exit);
1246
1247MODULE_ALIAS_RTNL_LINK("can");
1248