2 * Copyright (C) 2005 Marc Kleine-Budde, Pengutronix
3 * Copyright (C) 2006 Andrey Volkov, Varma Electronics
4 * Copyright (C) 2008-2009 Wolfgang Grandegger <wg@grandegger.com>
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the version 2 of the GNU General Public License
8 * as published by the Free Software Foundation
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, see <http://www.gnu.org/licenses/>.
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/can.h>
25 #include <linux/can/dev.h>
26 #include <linux/can/skb.h>
27 #include <linux/can/netlink.h>
28 #include <linux/can/led.h>
29 #include <net/rtnetlink.h>
31 #define MOD_DESC "CAN device driver interface"
33 MODULE_DESCRIPTION(MOD_DESC);
34 MODULE_LICENSE("GPL v2");
35 MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
37 /* CAN DLC to real data length conversion helpers */
39 static const u8 dlc2len[] = {0, 1, 2, 3, 4, 5, 6, 7,
40 8, 12, 16, 20, 24, 32, 48, 64};
42 /* get data length from can_dlc with sanitized can_dlc */
43 u8 can_dlc2len(u8 can_dlc)
45 return dlc2len[can_dlc & 0x0F];
47 EXPORT_SYMBOL_GPL(can_dlc2len);
49 static const u8 len2dlc[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, /* 0 - 8 */
50 9, 9, 9, 9, /* 9 - 12 */
51 10, 10, 10, 10, /* 13 - 16 */
52 11, 11, 11, 11, /* 17 - 20 */
53 12, 12, 12, 12, /* 21 - 24 */
54 13, 13, 13, 13, 13, 13, 13, 13, /* 25 - 32 */
55 14, 14, 14, 14, 14, 14, 14, 14, /* 33 - 40 */
56 14, 14, 14, 14, 14, 14, 14, 14, /* 41 - 48 */
57 15, 15, 15, 15, 15, 15, 15, 15, /* 49 - 56 */
58 15, 15, 15, 15, 15, 15, 15, 15}; /* 57 - 64 */
60 /* map the sanitized data length to an appropriate data length code */
61 u8 can_len2dlc(u8 len)
63 if (unlikely(len > 64))
68 EXPORT_SYMBOL_GPL(can_len2dlc);
70 #ifdef CONFIG_CAN_CALC_BITTIMING
71 #define CAN_CALC_MAX_ERROR 50 /* in one-tenth of a percent */
74 * Bit-timing calculation derived from:
76 * Code based on LinCAN sources and H8S2638 project
77 * Copyright 2004-2006 Pavel Pisa - DCE FELK CVUT cz
78 * Copyright 2005 Stanislav Marek
79 * email: pisa@cmp.felk.cvut.cz
81 * Calculates proper bit-timing parameters for a specified bit-rate
82 * and sample-point, which can then be used to set the bit-timing
83 * registers of the CAN controller. You can find more information
84 * in the header file linux/can/netlink.h.
86 static int can_update_spt(const struct can_bittiming_const *btc,
87 int sampl_pt, int tseg, int *tseg1, int *tseg2)
89 *tseg2 = tseg + 1 - (sampl_pt * (tseg + 1)) / 1000;
90 if (*tseg2 < btc->tseg2_min)
91 *tseg2 = btc->tseg2_min;
92 if (*tseg2 > btc->tseg2_max)
93 *tseg2 = btc->tseg2_max;
94 *tseg1 = tseg - *tseg2;
95 if (*tseg1 > btc->tseg1_max) {
96 *tseg1 = btc->tseg1_max;
97 *tseg2 = tseg - *tseg1;
99 return 1000 * (tseg + 1 - *tseg2) / (tseg + 1);
102 static int can_calc_bittiming(struct net_device *dev, struct can_bittiming *bt,
103 const struct can_bittiming_const *btc)
105 struct can_priv *priv = netdev_priv(dev);
106 long best_error = 1000000000, error = 0;
107 int best_tseg = 0, best_brp = 0, brp = 0;
108 int tsegall, tseg = 0, tseg1 = 0, tseg2 = 0;
109 int spt_error = 1000, spt = 0, sampl_pt;
113 /* Use CiA recommended sample points */
114 if (bt->sample_point) {
115 sampl_pt = bt->sample_point;
117 if (bt->bitrate > 800000)
119 else if (bt->bitrate > 500000)
125 /* tseg even = round down, odd = round up */
126 for (tseg = (btc->tseg1_max + btc->tseg2_max) * 2 + 1;
127 tseg >= (btc->tseg1_min + btc->tseg2_min) * 2; tseg--) {
128 tsegall = 1 + tseg / 2;
129 /* Compute all possible tseg choices (tseg=tseg1+tseg2) */
130 brp = priv->clock.freq / (tsegall * bt->bitrate) + tseg % 2;
131 /* chose brp step which is possible in system */
132 brp = (brp / btc->brp_inc) * btc->brp_inc;
133 if ((brp < btc->brp_min) || (brp > btc->brp_max))
135 rate = priv->clock.freq / (brp * tsegall);
136 error = bt->bitrate - rate;
137 /* tseg brp biterror */
140 if (error > best_error)
144 spt = can_update_spt(btc, sampl_pt, tseg / 2,
146 error = sampl_pt - spt;
149 if (error > spt_error)
153 best_tseg = tseg / 2;
160 /* Error in one-tenth of a percent */
161 error = (best_error * 1000) / bt->bitrate;
162 if (error > CAN_CALC_MAX_ERROR) {
164 "bitrate error %ld.%ld%% too high\n",
165 error / 10, error % 10);
168 netdev_warn(dev, "bitrate error %ld.%ld%%\n",
169 error / 10, error % 10);
173 /* real sample point */
174 bt->sample_point = can_update_spt(btc, sampl_pt, best_tseg,
177 v64 = (u64)best_brp * 1000000000UL;
178 do_div(v64, priv->clock.freq);
180 bt->prop_seg = tseg1 / 2;
181 bt->phase_seg1 = tseg1 - bt->prop_seg;
182 bt->phase_seg2 = tseg2;
184 /* check for sjw user settings */
185 if (!bt->sjw || !btc->sjw_max)
188 /* bt->sjw is at least 1 -> sanitize upper bound to sjw_max */
189 if (bt->sjw > btc->sjw_max)
190 bt->sjw = btc->sjw_max;
191 /* bt->sjw must not be higher than tseg2 */
198 bt->bitrate = priv->clock.freq / (bt->brp * (tseg1 + tseg2 + 1));
202 #else /* !CONFIG_CAN_CALC_BITTIMING */
203 static int can_calc_bittiming(struct net_device *dev, struct can_bittiming *bt,
204 const struct can_bittiming_const *btc)
206 netdev_err(dev, "bit-timing calculation not available\n");
209 #endif /* CONFIG_CAN_CALC_BITTIMING */
212 * Checks the validity of the specified bit-timing parameters prop_seg,
213 * phase_seg1, phase_seg2 and sjw and tries to determine the bitrate
214 * prescaler value brp. You can find more information in the header
215 * file linux/can/netlink.h.
217 static int can_fixup_bittiming(struct net_device *dev, struct can_bittiming *bt,
218 const struct can_bittiming_const *btc)
220 struct can_priv *priv = netdev_priv(dev);
224 tseg1 = bt->prop_seg + bt->phase_seg1;
227 if (bt->sjw > btc->sjw_max ||
228 tseg1 < btc->tseg1_min || tseg1 > btc->tseg1_max ||
229 bt->phase_seg2 < btc->tseg2_min || bt->phase_seg2 > btc->tseg2_max)
232 brp64 = (u64)priv->clock.freq * (u64)bt->tq;
233 if (btc->brp_inc > 1)
234 do_div(brp64, btc->brp_inc);
235 brp64 += 500000000UL - 1;
236 do_div(brp64, 1000000000UL); /* the practicable BRP */
237 if (btc->brp_inc > 1)
238 brp64 *= btc->brp_inc;
239 bt->brp = (u32)brp64;
241 if (bt->brp < btc->brp_min || bt->brp > btc->brp_max)
244 alltseg = bt->prop_seg + bt->phase_seg1 + bt->phase_seg2 + 1;
245 bt->bitrate = priv->clock.freq / (bt->brp * alltseg);
246 bt->sample_point = ((tseg1 + 1) * 1000) / alltseg;
251 static int can_get_bittiming(struct net_device *dev, struct can_bittiming *bt,
252 const struct can_bittiming_const *btc)
256 /* Check if the CAN device has bit-timing parameters */
261 * Depending on the given can_bittiming parameter structure the CAN
262 * timing parameters are calculated based on the provided bitrate OR
263 * alternatively the CAN timing parameters (tq, prop_seg, etc.) are
264 * provided directly which are then checked and fixed up.
266 if (!bt->tq && bt->bitrate)
267 err = can_calc_bittiming(dev, bt, btc);
268 else if (bt->tq && !bt->bitrate)
269 err = can_fixup_bittiming(dev, bt, btc);
276 static void can_update_state_error_stats(struct net_device *dev,
277 enum can_state new_state)
279 struct can_priv *priv = netdev_priv(dev);
281 if (new_state <= priv->state)
285 case CAN_STATE_ERROR_WARNING:
286 priv->can_stats.error_warning++;
288 case CAN_STATE_ERROR_PASSIVE:
289 priv->can_stats.error_passive++;
291 case CAN_STATE_BUS_OFF:
292 priv->can_stats.bus_off++;
299 static int can_tx_state_to_frame(struct net_device *dev, enum can_state state)
302 case CAN_STATE_ERROR_ACTIVE:
303 return CAN_ERR_CRTL_ACTIVE;
304 case CAN_STATE_ERROR_WARNING:
305 return CAN_ERR_CRTL_TX_WARNING;
306 case CAN_STATE_ERROR_PASSIVE:
307 return CAN_ERR_CRTL_TX_PASSIVE;
313 static int can_rx_state_to_frame(struct net_device *dev, enum can_state state)
316 case CAN_STATE_ERROR_ACTIVE:
317 return CAN_ERR_CRTL_ACTIVE;
318 case CAN_STATE_ERROR_WARNING:
319 return CAN_ERR_CRTL_RX_WARNING;
320 case CAN_STATE_ERROR_PASSIVE:
321 return CAN_ERR_CRTL_RX_PASSIVE;
327 void can_change_state(struct net_device *dev, struct can_frame *cf,
328 enum can_state tx_state, enum can_state rx_state)
330 struct can_priv *priv = netdev_priv(dev);
331 enum can_state new_state = max(tx_state, rx_state);
333 if (unlikely(new_state == priv->state)) {
334 netdev_warn(dev, "%s: oops, state did not change", __func__);
338 netdev_dbg(dev, "New error state: %d\n", new_state);
340 can_update_state_error_stats(dev, new_state);
341 priv->state = new_state;
343 if (unlikely(new_state == CAN_STATE_BUS_OFF)) {
344 cf->can_id |= CAN_ERR_BUSOFF;
348 cf->can_id |= CAN_ERR_CRTL;
349 cf->data[1] |= tx_state >= rx_state ?
350 can_tx_state_to_frame(dev, tx_state) : 0;
351 cf->data[1] |= tx_state <= rx_state ?
352 can_rx_state_to_frame(dev, rx_state) : 0;
354 EXPORT_SYMBOL_GPL(can_change_state);
357 * Local echo of CAN messages
359 * CAN network devices *should* support a local echo functionality
360 * (see Documentation/networking/can.txt). To test the handling of CAN
361 * interfaces that do not support the local echo both driver types are
362 * implemented. In the case that the driver does not support the echo
363 * the IFF_ECHO remains clear in dev->flags. This causes the PF_CAN core
364 * to perform the echo as a fallback solution.
366 static void can_flush_echo_skb(struct net_device *dev)
368 struct can_priv *priv = netdev_priv(dev);
369 struct net_device_stats *stats = &dev->stats;
372 for (i = 0; i < priv->echo_skb_max; i++) {
373 if (priv->echo_skb[i]) {
374 kfree_skb(priv->echo_skb[i]);
375 priv->echo_skb[i] = NULL;
377 stats->tx_aborted_errors++;
383 * Put the skb on the stack to be looped backed locally lateron
385 * The function is typically called in the start_xmit function
386 * of the device driver. The driver must protect access to
387 * priv->echo_skb, if necessary.
389 void can_put_echo_skb(struct sk_buff *skb, struct net_device *dev,
392 struct can_priv *priv = netdev_priv(dev);
394 BUG_ON(idx >= priv->echo_skb_max);
396 /* check flag whether this packet has to be looped back */
397 if (!(dev->flags & IFF_ECHO) || skb->pkt_type != PACKET_LOOPBACK ||
398 (skb->protocol != htons(ETH_P_CAN) &&
399 skb->protocol != htons(ETH_P_CANFD))) {
404 if (!priv->echo_skb[idx]) {
406 skb = can_create_echo_skb(skb);
410 /* make settings for echo to reduce code in irq context */
411 skb->pkt_type = PACKET_BROADCAST;
412 skb->ip_summed = CHECKSUM_UNNECESSARY;
415 /* save this skb for tx interrupt echo handling */
416 priv->echo_skb[idx] = skb;
418 /* locking problem with netif_stop_queue() ?? */
419 netdev_err(dev, "%s: BUG! echo_skb is occupied!\n", __func__);
423 EXPORT_SYMBOL_GPL(can_put_echo_skb);
426 * Get the skb from the stack and loop it back locally
428 * The function is typically called when the TX done interrupt
429 * is handled in the device driver. The driver must protect
430 * access to priv->echo_skb, if necessary.
432 unsigned int can_get_echo_skb(struct net_device *dev, unsigned int idx)
434 struct can_priv *priv = netdev_priv(dev);
436 BUG_ON(idx >= priv->echo_skb_max);
438 if (priv->echo_skb[idx]) {
439 struct sk_buff *skb = priv->echo_skb[idx];
440 struct can_frame *cf = (struct can_frame *)skb->data;
441 u8 dlc = cf->can_dlc;
443 if (!(skb->tstamp.tv64))
444 __net_timestamp(skb);
446 netif_rx(priv->echo_skb[idx]);
447 priv->echo_skb[idx] = NULL;
454 EXPORT_SYMBOL_GPL(can_get_echo_skb);
457 * Remove the skb from the stack and free it.
459 * The function is typically called when TX failed.
461 void can_free_echo_skb(struct net_device *dev, unsigned int idx)
463 struct can_priv *priv = netdev_priv(dev);
465 BUG_ON(idx >= priv->echo_skb_max);
467 if (priv->echo_skb[idx]) {
468 dev_kfree_skb_any(priv->echo_skb[idx]);
469 priv->echo_skb[idx] = NULL;
472 EXPORT_SYMBOL_GPL(can_free_echo_skb);
475 * CAN device restart for bus-off recovery
477 static void can_restart(unsigned long data)
479 struct net_device *dev = (struct net_device *)data;
480 struct can_priv *priv = netdev_priv(dev);
481 struct net_device_stats *stats = &dev->stats;
483 struct can_frame *cf;
486 BUG_ON(netif_carrier_ok(dev));
489 * No synchronization needed because the device is bus-off and
490 * no messages can come in or go out.
492 can_flush_echo_skb(dev);
494 /* send restart message upstream */
495 skb = alloc_can_err_skb(dev, &cf);
500 cf->can_id |= CAN_ERR_RESTARTED;
505 stats->rx_bytes += cf->can_dlc;
508 netdev_dbg(dev, "restarted\n");
509 priv->can_stats.restarts++;
511 /* Now restart the device */
512 err = priv->do_set_mode(dev, CAN_MODE_START);
514 netif_carrier_on(dev);
516 netdev_err(dev, "Error %d during restart", err);
519 int can_restart_now(struct net_device *dev)
521 struct can_priv *priv = netdev_priv(dev);
524 * A manual restart is only permitted if automatic restart is
525 * disabled and the device is in the bus-off state
527 if (priv->restart_ms)
529 if (priv->state != CAN_STATE_BUS_OFF)
532 /* Runs as soon as possible in the timer context */
533 mod_timer(&priv->restart_timer, jiffies);
541 * This functions should be called when the device goes bus-off to
542 * tell the netif layer that no more packets can be sent or received.
543 * If enabled, a timer is started to trigger bus-off recovery.
545 void can_bus_off(struct net_device *dev)
547 struct can_priv *priv = netdev_priv(dev);
549 netdev_dbg(dev, "bus-off\n");
551 netif_carrier_off(dev);
553 if (priv->restart_ms)
554 mod_timer(&priv->restart_timer,
555 jiffies + (priv->restart_ms * HZ) / 1000);
557 EXPORT_SYMBOL_GPL(can_bus_off);
559 static void can_setup(struct net_device *dev)
561 dev->type = ARPHRD_CAN;
563 dev->hard_header_len = 0;
565 dev->tx_queue_len = 10;
567 /* New-style flags. */
568 dev->flags = IFF_NOARP;
569 dev->features = NETIF_F_HW_CSUM;
572 struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf)
576 skb = netdev_alloc_skb(dev, sizeof(struct can_skb_priv) +
577 sizeof(struct can_frame));
581 __net_timestamp(skb);
582 skb->protocol = htons(ETH_P_CAN);
583 skb->pkt_type = PACKET_BROADCAST;
584 skb->ip_summed = CHECKSUM_UNNECESSARY;
586 skb_reset_mac_header(skb);
587 skb_reset_network_header(skb);
588 skb_reset_transport_header(skb);
590 can_skb_reserve(skb);
591 can_skb_prv(skb)->ifindex = dev->ifindex;
593 *cf = (struct can_frame *)skb_put(skb, sizeof(struct can_frame));
594 memset(*cf, 0, sizeof(struct can_frame));
598 EXPORT_SYMBOL_GPL(alloc_can_skb);
600 struct sk_buff *alloc_canfd_skb(struct net_device *dev,
601 struct canfd_frame **cfd)
605 skb = netdev_alloc_skb(dev, sizeof(struct can_skb_priv) +
606 sizeof(struct canfd_frame));
610 __net_timestamp(skb);
611 skb->protocol = htons(ETH_P_CANFD);
612 skb->pkt_type = PACKET_BROADCAST;
613 skb->ip_summed = CHECKSUM_UNNECESSARY;
615 skb_reset_mac_header(skb);
616 skb_reset_network_header(skb);
617 skb_reset_transport_header(skb);
619 can_skb_reserve(skb);
620 can_skb_prv(skb)->ifindex = dev->ifindex;
622 *cfd = (struct canfd_frame *)skb_put(skb, sizeof(struct canfd_frame));
623 memset(*cfd, 0, sizeof(struct canfd_frame));
627 EXPORT_SYMBOL_GPL(alloc_canfd_skb);
629 struct sk_buff *alloc_can_err_skb(struct net_device *dev, struct can_frame **cf)
633 skb = alloc_can_skb(dev, cf);
637 (*cf)->can_id = CAN_ERR_FLAG;
638 (*cf)->can_dlc = CAN_ERR_DLC;
642 EXPORT_SYMBOL_GPL(alloc_can_err_skb);
645 * Allocate and setup space for the CAN network device
647 struct net_device *alloc_candev(int sizeof_priv, unsigned int echo_skb_max)
649 struct net_device *dev;
650 struct can_priv *priv;
654 size = ALIGN(sizeof_priv, sizeof(struct sk_buff *)) +
655 echo_skb_max * sizeof(struct sk_buff *);
659 dev = alloc_netdev(size, "can%d", NET_NAME_UNKNOWN, can_setup);
663 priv = netdev_priv(dev);
666 priv->echo_skb_max = echo_skb_max;
667 priv->echo_skb = (void *)priv +
668 ALIGN(sizeof_priv, sizeof(struct sk_buff *));
671 priv->state = CAN_STATE_STOPPED;
673 init_timer(&priv->restart_timer);
677 EXPORT_SYMBOL_GPL(alloc_candev);
680 * Free space of the CAN network device
682 void free_candev(struct net_device *dev)
686 EXPORT_SYMBOL_GPL(free_candev);
689 * changing MTU and control mode for CAN/CANFD devices
691 int can_change_mtu(struct net_device *dev, int new_mtu)
693 struct can_priv *priv = netdev_priv(dev);
695 /* Do not allow changing the MTU while running */
696 if (dev->flags & IFF_UP)
699 /* allow change of MTU according to the CANFD ability of the device */
702 priv->ctrlmode &= ~CAN_CTRLMODE_FD;
706 if (!(priv->ctrlmode_supported & CAN_CTRLMODE_FD))
709 priv->ctrlmode |= CAN_CTRLMODE_FD;
719 EXPORT_SYMBOL_GPL(can_change_mtu);
722 * Common open function when the device gets opened.
724 * This function should be called in the open function of the device
727 int open_candev(struct net_device *dev)
729 struct can_priv *priv = netdev_priv(dev);
731 if (!priv->bittiming.bitrate) {
732 netdev_err(dev, "bit-timing not yet defined\n");
736 /* For CAN FD the data bitrate has to be >= the arbitration bitrate */
737 if ((priv->ctrlmode & CAN_CTRLMODE_FD) &&
738 (!priv->data_bittiming.bitrate ||
739 (priv->data_bittiming.bitrate < priv->bittiming.bitrate))) {
740 netdev_err(dev, "incorrect/missing data bit-timing\n");
744 /* Switch carrier on if device was stopped while in bus-off state */
745 if (!netif_carrier_ok(dev))
746 netif_carrier_on(dev);
748 setup_timer(&priv->restart_timer, can_restart, (unsigned long)dev);
752 EXPORT_SYMBOL_GPL(open_candev);
755 * Common close function for cleanup before the device gets closed.
757 * This function should be called in the close function of the device
760 void close_candev(struct net_device *dev)
762 struct can_priv *priv = netdev_priv(dev);
764 del_timer_sync(&priv->restart_timer);
765 can_flush_echo_skb(dev);
767 EXPORT_SYMBOL_GPL(close_candev);
770 * CAN netlink interface
772 static const struct nla_policy can_policy[IFLA_CAN_MAX + 1] = {
773 [IFLA_CAN_STATE] = { .type = NLA_U32 },
774 [IFLA_CAN_CTRLMODE] = { .len = sizeof(struct can_ctrlmode) },
775 [IFLA_CAN_RESTART_MS] = { .type = NLA_U32 },
776 [IFLA_CAN_RESTART] = { .type = NLA_U32 },
777 [IFLA_CAN_BITTIMING] = { .len = sizeof(struct can_bittiming) },
778 [IFLA_CAN_BITTIMING_CONST]
779 = { .len = sizeof(struct can_bittiming_const) },
780 [IFLA_CAN_CLOCK] = { .len = sizeof(struct can_clock) },
781 [IFLA_CAN_BERR_COUNTER] = { .len = sizeof(struct can_berr_counter) },
782 [IFLA_CAN_DATA_BITTIMING]
783 = { .len = sizeof(struct can_bittiming) },
784 [IFLA_CAN_DATA_BITTIMING_CONST]
785 = { .len = sizeof(struct can_bittiming_const) },
788 static int can_changelink(struct net_device *dev,
789 struct nlattr *tb[], struct nlattr *data[])
791 struct can_priv *priv = netdev_priv(dev);
794 /* We need synchronization with dev->stop() */
797 if (data[IFLA_CAN_BITTIMING]) {
798 struct can_bittiming bt;
800 /* Do not allow changing bittiming while running */
801 if (dev->flags & IFF_UP)
803 memcpy(&bt, nla_data(data[IFLA_CAN_BITTIMING]), sizeof(bt));
804 err = can_get_bittiming(dev, &bt, priv->bittiming_const);
807 memcpy(&priv->bittiming, &bt, sizeof(bt));
809 if (priv->do_set_bittiming) {
810 /* Finally, set the bit-timing registers */
811 err = priv->do_set_bittiming(dev);
817 if (data[IFLA_CAN_CTRLMODE]) {
818 struct can_ctrlmode *cm;
820 /* Do not allow changing controller mode while running */
821 if (dev->flags & IFF_UP)
823 cm = nla_data(data[IFLA_CAN_CTRLMODE]);
825 /* check whether changed bits are allowed to be modified */
826 if (cm->mask & ~priv->ctrlmode_supported)
829 /* clear bits to be modified and copy the flag values */
830 priv->ctrlmode &= ~cm->mask;
831 priv->ctrlmode |= (cm->flags & cm->mask);
833 /* CAN_CTRLMODE_FD can only be set when driver supports FD */
834 if (priv->ctrlmode & CAN_CTRLMODE_FD)
835 dev->mtu = CANFD_MTU;
840 if (data[IFLA_CAN_RESTART_MS]) {
841 /* Do not allow changing restart delay while running */
842 if (dev->flags & IFF_UP)
844 priv->restart_ms = nla_get_u32(data[IFLA_CAN_RESTART_MS]);
847 if (data[IFLA_CAN_RESTART]) {
848 /* Do not allow a restart while not running */
849 if (!(dev->flags & IFF_UP))
851 err = can_restart_now(dev);
856 if (data[IFLA_CAN_DATA_BITTIMING]) {
857 struct can_bittiming dbt;
859 /* Do not allow changing bittiming while running */
860 if (dev->flags & IFF_UP)
862 memcpy(&dbt, nla_data(data[IFLA_CAN_DATA_BITTIMING]),
864 err = can_get_bittiming(dev, &dbt, priv->data_bittiming_const);
867 memcpy(&priv->data_bittiming, &dbt, sizeof(dbt));
869 if (priv->do_set_data_bittiming) {
870 /* Finally, set the bit-timing registers */
871 err = priv->do_set_data_bittiming(dev);
880 static size_t can_get_size(const struct net_device *dev)
882 struct can_priv *priv = netdev_priv(dev);
885 if (priv->bittiming.bitrate) /* IFLA_CAN_BITTIMING */
886 size += nla_total_size(sizeof(struct can_bittiming));
887 if (priv->bittiming_const) /* IFLA_CAN_BITTIMING_CONST */
888 size += nla_total_size(sizeof(struct can_bittiming_const));
889 size += nla_total_size(sizeof(struct can_clock)); /* IFLA_CAN_CLOCK */
890 size += nla_total_size(sizeof(u32)); /* IFLA_CAN_STATE */
891 size += nla_total_size(sizeof(struct can_ctrlmode)); /* IFLA_CAN_CTRLMODE */
892 size += nla_total_size(sizeof(u32)); /* IFLA_CAN_RESTART_MS */
893 if (priv->do_get_berr_counter) /* IFLA_CAN_BERR_COUNTER */
894 size += nla_total_size(sizeof(struct can_berr_counter));
895 if (priv->data_bittiming.bitrate) /* IFLA_CAN_DATA_BITTIMING */
896 size += nla_total_size(sizeof(struct can_bittiming));
897 if (priv->data_bittiming_const) /* IFLA_CAN_DATA_BITTIMING_CONST */
898 size += nla_total_size(sizeof(struct can_bittiming_const));
903 static int can_fill_info(struct sk_buff *skb, const struct net_device *dev)
905 struct can_priv *priv = netdev_priv(dev);
906 struct can_ctrlmode cm = {.flags = priv->ctrlmode};
907 struct can_berr_counter bec;
908 enum can_state state = priv->state;
910 if (priv->do_get_state)
911 priv->do_get_state(dev, &state);
913 if ((priv->bittiming.bitrate &&
914 nla_put(skb, IFLA_CAN_BITTIMING,
915 sizeof(priv->bittiming), &priv->bittiming)) ||
917 (priv->bittiming_const &&
918 nla_put(skb, IFLA_CAN_BITTIMING_CONST,
919 sizeof(*priv->bittiming_const), priv->bittiming_const)) ||
921 nla_put(skb, IFLA_CAN_CLOCK, sizeof(cm), &priv->clock) ||
922 nla_put_u32(skb, IFLA_CAN_STATE, state) ||
923 nla_put(skb, IFLA_CAN_CTRLMODE, sizeof(cm), &cm) ||
924 nla_put_u32(skb, IFLA_CAN_RESTART_MS, priv->restart_ms) ||
926 (priv->do_get_berr_counter &&
927 !priv->do_get_berr_counter(dev, &bec) &&
928 nla_put(skb, IFLA_CAN_BERR_COUNTER, sizeof(bec), &bec)) ||
930 (priv->data_bittiming.bitrate &&
931 nla_put(skb, IFLA_CAN_DATA_BITTIMING,
932 sizeof(priv->data_bittiming), &priv->data_bittiming)) ||
934 (priv->data_bittiming_const &&
935 nla_put(skb, IFLA_CAN_DATA_BITTIMING_CONST,
936 sizeof(*priv->data_bittiming_const),
937 priv->data_bittiming_const)))
943 static size_t can_get_xstats_size(const struct net_device *dev)
945 return sizeof(struct can_device_stats);
948 static int can_fill_xstats(struct sk_buff *skb, const struct net_device *dev)
950 struct can_priv *priv = netdev_priv(dev);
952 if (nla_put(skb, IFLA_INFO_XSTATS,
953 sizeof(priv->can_stats), &priv->can_stats))
954 goto nla_put_failure;
961 static int can_newlink(struct net *src_net, struct net_device *dev,
962 struct nlattr *tb[], struct nlattr *data[])
967 static struct rtnl_link_ops can_link_ops __read_mostly = {
969 .maxtype = IFLA_CAN_MAX,
970 .policy = can_policy,
972 .newlink = can_newlink,
973 .changelink = can_changelink,
974 .get_size = can_get_size,
975 .fill_info = can_fill_info,
976 .get_xstats_size = can_get_xstats_size,
977 .fill_xstats = can_fill_xstats,
981 * Register the CAN network device
983 int register_candev(struct net_device *dev)
985 dev->rtnl_link_ops = &can_link_ops;
986 return register_netdev(dev);
988 EXPORT_SYMBOL_GPL(register_candev);
991 * Unregister the CAN network device
993 void unregister_candev(struct net_device *dev)
995 unregister_netdev(dev);
997 EXPORT_SYMBOL_GPL(unregister_candev);
1000 * Test if a network device is a candev based device
1001 * and return the can_priv* if so.
1003 struct can_priv *safe_candev_priv(struct net_device *dev)
1005 if ((dev->type != ARPHRD_CAN) || (dev->rtnl_link_ops != &can_link_ops))
1008 return netdev_priv(dev);
1010 EXPORT_SYMBOL_GPL(safe_candev_priv);
1012 static __init int can_dev_init(void)
1016 can_led_notifier_init();
1018 err = rtnl_link_register(&can_link_ops);
1020 printk(KERN_INFO MOD_DESC "\n");
1024 module_init(can_dev_init);
1026 static __exit void can_dev_exit(void)
1028 rtnl_link_unregister(&can_link_ops);
1030 can_led_notifier_exit();
1032 module_exit(can_dev_exit);
1034 MODULE_ALIAS_RTNL_LINK("can");