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 netif_rx(priv->echo_skb[idx]);
444 priv->echo_skb[idx] = NULL;
451 EXPORT_SYMBOL_GPL(can_get_echo_skb);
454 * Remove the skb from the stack and free it.
456 * The function is typically called when TX failed.
458 void can_free_echo_skb(struct net_device *dev, unsigned int idx)
460 struct can_priv *priv = netdev_priv(dev);
462 BUG_ON(idx >= priv->echo_skb_max);
464 if (priv->echo_skb[idx]) {
465 dev_kfree_skb_any(priv->echo_skb[idx]);
466 priv->echo_skb[idx] = NULL;
469 EXPORT_SYMBOL_GPL(can_free_echo_skb);
472 * CAN device restart for bus-off recovery
474 static void can_restart(unsigned long data)
476 struct net_device *dev = (struct net_device *)data;
477 struct can_priv *priv = netdev_priv(dev);
478 struct net_device_stats *stats = &dev->stats;
480 struct can_frame *cf;
483 BUG_ON(netif_carrier_ok(dev));
486 * No synchronization needed because the device is bus-off and
487 * no messages can come in or go out.
489 can_flush_echo_skb(dev);
491 /* send restart message upstream */
492 skb = alloc_can_err_skb(dev, &cf);
497 cf->can_id |= CAN_ERR_RESTARTED;
502 stats->rx_bytes += cf->can_dlc;
505 netdev_dbg(dev, "restarted\n");
506 priv->can_stats.restarts++;
508 /* Now restart the device */
509 err = priv->do_set_mode(dev, CAN_MODE_START);
511 netif_carrier_on(dev);
513 netdev_err(dev, "Error %d during restart", err);
516 int can_restart_now(struct net_device *dev)
518 struct can_priv *priv = netdev_priv(dev);
521 * A manual restart is only permitted if automatic restart is
522 * disabled and the device is in the bus-off state
524 if (priv->restart_ms)
526 if (priv->state != CAN_STATE_BUS_OFF)
529 /* Runs as soon as possible in the timer context */
530 mod_timer(&priv->restart_timer, jiffies);
538 * This functions should be called when the device goes bus-off to
539 * tell the netif layer that no more packets can be sent or received.
540 * If enabled, a timer is started to trigger bus-off recovery.
542 void can_bus_off(struct net_device *dev)
544 struct can_priv *priv = netdev_priv(dev);
546 netdev_dbg(dev, "bus-off\n");
548 netif_carrier_off(dev);
550 if (priv->restart_ms)
551 mod_timer(&priv->restart_timer,
552 jiffies + (priv->restart_ms * HZ) / 1000);
554 EXPORT_SYMBOL_GPL(can_bus_off);
556 static void can_setup(struct net_device *dev)
558 dev->type = ARPHRD_CAN;
560 dev->hard_header_len = 0;
562 dev->tx_queue_len = 10;
564 /* New-style flags. */
565 dev->flags = IFF_NOARP;
566 dev->features = NETIF_F_HW_CSUM;
569 struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf)
573 skb = netdev_alloc_skb(dev, sizeof(struct can_skb_priv) +
574 sizeof(struct can_frame));
578 skb->protocol = htons(ETH_P_CAN);
579 skb->pkt_type = PACKET_BROADCAST;
580 skb->ip_summed = CHECKSUM_UNNECESSARY;
582 skb_reset_mac_header(skb);
583 skb_reset_network_header(skb);
584 skb_reset_transport_header(skb);
586 can_skb_reserve(skb);
587 can_skb_prv(skb)->ifindex = dev->ifindex;
588 can_skb_prv(skb)->skbcnt = 0;
590 *cf = (struct can_frame *)skb_put(skb, sizeof(struct can_frame));
591 memset(*cf, 0, sizeof(struct can_frame));
595 EXPORT_SYMBOL_GPL(alloc_can_skb);
597 struct sk_buff *alloc_canfd_skb(struct net_device *dev,
598 struct canfd_frame **cfd)
602 skb = netdev_alloc_skb(dev, sizeof(struct can_skb_priv) +
603 sizeof(struct canfd_frame));
607 skb->protocol = htons(ETH_P_CANFD);
608 skb->pkt_type = PACKET_BROADCAST;
609 skb->ip_summed = CHECKSUM_UNNECESSARY;
611 skb_reset_mac_header(skb);
612 skb_reset_network_header(skb);
613 skb_reset_transport_header(skb);
615 can_skb_reserve(skb);
616 can_skb_prv(skb)->ifindex = dev->ifindex;
617 can_skb_prv(skb)->skbcnt = 0;
619 *cfd = (struct canfd_frame *)skb_put(skb, sizeof(struct canfd_frame));
620 memset(*cfd, 0, sizeof(struct canfd_frame));
624 EXPORT_SYMBOL_GPL(alloc_canfd_skb);
626 struct sk_buff *alloc_can_err_skb(struct net_device *dev, struct can_frame **cf)
630 skb = alloc_can_skb(dev, cf);
634 (*cf)->can_id = CAN_ERR_FLAG;
635 (*cf)->can_dlc = CAN_ERR_DLC;
639 EXPORT_SYMBOL_GPL(alloc_can_err_skb);
642 * Allocate and setup space for the CAN network device
644 struct net_device *alloc_candev(int sizeof_priv, unsigned int echo_skb_max)
646 struct net_device *dev;
647 struct can_priv *priv;
651 size = ALIGN(sizeof_priv, sizeof(struct sk_buff *)) +
652 echo_skb_max * sizeof(struct sk_buff *);
656 dev = alloc_netdev(size, "can%d", NET_NAME_UNKNOWN, can_setup);
660 priv = netdev_priv(dev);
663 priv->echo_skb_max = echo_skb_max;
664 priv->echo_skb = (void *)priv +
665 ALIGN(sizeof_priv, sizeof(struct sk_buff *));
668 priv->state = CAN_STATE_STOPPED;
670 init_timer(&priv->restart_timer);
674 EXPORT_SYMBOL_GPL(alloc_candev);
677 * Free space of the CAN network device
679 void free_candev(struct net_device *dev)
683 EXPORT_SYMBOL_GPL(free_candev);
686 * changing MTU and control mode for CAN/CANFD devices
688 int can_change_mtu(struct net_device *dev, int new_mtu)
690 struct can_priv *priv = netdev_priv(dev);
692 /* Do not allow changing the MTU while running */
693 if (dev->flags & IFF_UP)
696 /* allow change of MTU according to the CANFD ability of the device */
699 /* 'CANFD-only' controllers can not switch to CAN_MTU */
700 if (priv->ctrlmode_static & CAN_CTRLMODE_FD)
703 priv->ctrlmode &= ~CAN_CTRLMODE_FD;
707 /* check for potential CANFD ability */
708 if (!(priv->ctrlmode_supported & CAN_CTRLMODE_FD) &&
709 !(priv->ctrlmode_static & CAN_CTRLMODE_FD))
712 priv->ctrlmode |= CAN_CTRLMODE_FD;
722 EXPORT_SYMBOL_GPL(can_change_mtu);
725 * Common open function when the device gets opened.
727 * This function should be called in the open function of the device
730 int open_candev(struct net_device *dev)
732 struct can_priv *priv = netdev_priv(dev);
734 if (!priv->bittiming.bitrate) {
735 netdev_err(dev, "bit-timing not yet defined\n");
739 /* For CAN FD the data bitrate has to be >= the arbitration bitrate */
740 if ((priv->ctrlmode & CAN_CTRLMODE_FD) &&
741 (!priv->data_bittiming.bitrate ||
742 (priv->data_bittiming.bitrate < priv->bittiming.bitrate))) {
743 netdev_err(dev, "incorrect/missing data bit-timing\n");
747 /* Switch carrier on if device was stopped while in bus-off state */
748 if (!netif_carrier_ok(dev))
749 netif_carrier_on(dev);
751 setup_timer(&priv->restart_timer, can_restart, (unsigned long)dev);
755 EXPORT_SYMBOL_GPL(open_candev);
758 * Common close function for cleanup before the device gets closed.
760 * This function should be called in the close function of the device
763 void close_candev(struct net_device *dev)
765 struct can_priv *priv = netdev_priv(dev);
767 del_timer_sync(&priv->restart_timer);
768 can_flush_echo_skb(dev);
770 EXPORT_SYMBOL_GPL(close_candev);
773 * CAN netlink interface
775 static const struct nla_policy can_policy[IFLA_CAN_MAX + 1] = {
776 [IFLA_CAN_STATE] = { .type = NLA_U32 },
777 [IFLA_CAN_CTRLMODE] = { .len = sizeof(struct can_ctrlmode) },
778 [IFLA_CAN_RESTART_MS] = { .type = NLA_U32 },
779 [IFLA_CAN_RESTART] = { .type = NLA_U32 },
780 [IFLA_CAN_BITTIMING] = { .len = sizeof(struct can_bittiming) },
781 [IFLA_CAN_BITTIMING_CONST]
782 = { .len = sizeof(struct can_bittiming_const) },
783 [IFLA_CAN_CLOCK] = { .len = sizeof(struct can_clock) },
784 [IFLA_CAN_BERR_COUNTER] = { .len = sizeof(struct can_berr_counter) },
785 [IFLA_CAN_DATA_BITTIMING]
786 = { .len = sizeof(struct can_bittiming) },
787 [IFLA_CAN_DATA_BITTIMING_CONST]
788 = { .len = sizeof(struct can_bittiming_const) },
791 static int can_validate(struct nlattr *tb[], struct nlattr *data[])
793 bool is_can_fd = false;
795 /* Make sure that valid CAN FD configurations always consist of
796 * - nominal/arbitration bittiming
798 * - control mode with CAN_CTRLMODE_FD set
804 if (data[IFLA_CAN_CTRLMODE]) {
805 struct can_ctrlmode *cm = nla_data(data[IFLA_CAN_CTRLMODE]);
807 is_can_fd = cm->flags & cm->mask & CAN_CTRLMODE_FD;
811 if (!data[IFLA_CAN_BITTIMING] || !data[IFLA_CAN_DATA_BITTIMING])
815 if (data[IFLA_CAN_DATA_BITTIMING]) {
816 if (!is_can_fd || !data[IFLA_CAN_BITTIMING])
823 static int can_changelink(struct net_device *dev,
824 struct nlattr *tb[], struct nlattr *data[])
826 struct can_priv *priv = netdev_priv(dev);
829 /* We need synchronization with dev->stop() */
832 if (data[IFLA_CAN_BITTIMING]) {
833 struct can_bittiming bt;
835 /* Do not allow changing bittiming while running */
836 if (dev->flags & IFF_UP)
838 memcpy(&bt, nla_data(data[IFLA_CAN_BITTIMING]), sizeof(bt));
839 err = can_get_bittiming(dev, &bt, priv->bittiming_const);
842 memcpy(&priv->bittiming, &bt, sizeof(bt));
844 if (priv->do_set_bittiming) {
845 /* Finally, set the bit-timing registers */
846 err = priv->do_set_bittiming(dev);
852 if (data[IFLA_CAN_CTRLMODE]) {
853 struct can_ctrlmode *cm;
857 /* Do not allow changing controller mode while running */
858 if (dev->flags & IFF_UP)
860 cm = nla_data(data[IFLA_CAN_CTRLMODE]);
861 ctrlstatic = priv->ctrlmode_static;
862 maskedflags = cm->flags & cm->mask;
864 /* check whether provided bits are allowed to be passed */
865 if (cm->mask & ~(priv->ctrlmode_supported | ctrlstatic))
868 /* do not check for static fd-non-iso if 'fd' is disabled */
869 if (!(maskedflags & CAN_CTRLMODE_FD))
870 ctrlstatic &= ~CAN_CTRLMODE_FD_NON_ISO;
872 /* make sure static options are provided by configuration */
873 if ((maskedflags & ctrlstatic) != ctrlstatic)
876 /* clear bits to be modified and copy the flag values */
877 priv->ctrlmode &= ~cm->mask;
878 priv->ctrlmode |= maskedflags;
880 /* CAN_CTRLMODE_FD can only be set when driver supports FD */
881 if (priv->ctrlmode & CAN_CTRLMODE_FD)
882 dev->mtu = CANFD_MTU;
887 if (data[IFLA_CAN_RESTART_MS]) {
888 /* Do not allow changing restart delay while running */
889 if (dev->flags & IFF_UP)
891 priv->restart_ms = nla_get_u32(data[IFLA_CAN_RESTART_MS]);
894 if (data[IFLA_CAN_RESTART]) {
895 /* Do not allow a restart while not running */
896 if (!(dev->flags & IFF_UP))
898 err = can_restart_now(dev);
903 if (data[IFLA_CAN_DATA_BITTIMING]) {
904 struct can_bittiming dbt;
906 /* Do not allow changing bittiming while running */
907 if (dev->flags & IFF_UP)
909 memcpy(&dbt, nla_data(data[IFLA_CAN_DATA_BITTIMING]),
911 err = can_get_bittiming(dev, &dbt, priv->data_bittiming_const);
914 memcpy(&priv->data_bittiming, &dbt, sizeof(dbt));
916 if (priv->do_set_data_bittiming) {
917 /* Finally, set the bit-timing registers */
918 err = priv->do_set_data_bittiming(dev);
927 static size_t can_get_size(const struct net_device *dev)
929 struct can_priv *priv = netdev_priv(dev);
932 if (priv->bittiming.bitrate) /* IFLA_CAN_BITTIMING */
933 size += nla_total_size(sizeof(struct can_bittiming));
934 if (priv->bittiming_const) /* IFLA_CAN_BITTIMING_CONST */
935 size += nla_total_size(sizeof(struct can_bittiming_const));
936 size += nla_total_size(sizeof(struct can_clock)); /* IFLA_CAN_CLOCK */
937 size += nla_total_size(sizeof(u32)); /* IFLA_CAN_STATE */
938 size += nla_total_size(sizeof(struct can_ctrlmode)); /* IFLA_CAN_CTRLMODE */
939 size += nla_total_size(sizeof(u32)); /* IFLA_CAN_RESTART_MS */
940 if (priv->do_get_berr_counter) /* IFLA_CAN_BERR_COUNTER */
941 size += nla_total_size(sizeof(struct can_berr_counter));
942 if (priv->data_bittiming.bitrate) /* IFLA_CAN_DATA_BITTIMING */
943 size += nla_total_size(sizeof(struct can_bittiming));
944 if (priv->data_bittiming_const) /* IFLA_CAN_DATA_BITTIMING_CONST */
945 size += nla_total_size(sizeof(struct can_bittiming_const));
950 static int can_fill_info(struct sk_buff *skb, const struct net_device *dev)
952 struct can_priv *priv = netdev_priv(dev);
953 struct can_ctrlmode cm = {.flags = priv->ctrlmode};
954 struct can_berr_counter bec;
955 enum can_state state = priv->state;
957 if (priv->do_get_state)
958 priv->do_get_state(dev, &state);
960 if ((priv->bittiming.bitrate &&
961 nla_put(skb, IFLA_CAN_BITTIMING,
962 sizeof(priv->bittiming), &priv->bittiming)) ||
964 (priv->bittiming_const &&
965 nla_put(skb, IFLA_CAN_BITTIMING_CONST,
966 sizeof(*priv->bittiming_const), priv->bittiming_const)) ||
968 nla_put(skb, IFLA_CAN_CLOCK, sizeof(priv->clock), &priv->clock) ||
969 nla_put_u32(skb, IFLA_CAN_STATE, state) ||
970 nla_put(skb, IFLA_CAN_CTRLMODE, sizeof(cm), &cm) ||
971 nla_put_u32(skb, IFLA_CAN_RESTART_MS, priv->restart_ms) ||
973 (priv->do_get_berr_counter &&
974 !priv->do_get_berr_counter(dev, &bec) &&
975 nla_put(skb, IFLA_CAN_BERR_COUNTER, sizeof(bec), &bec)) ||
977 (priv->data_bittiming.bitrate &&
978 nla_put(skb, IFLA_CAN_DATA_BITTIMING,
979 sizeof(priv->data_bittiming), &priv->data_bittiming)) ||
981 (priv->data_bittiming_const &&
982 nla_put(skb, IFLA_CAN_DATA_BITTIMING_CONST,
983 sizeof(*priv->data_bittiming_const),
984 priv->data_bittiming_const)))
990 static size_t can_get_xstats_size(const struct net_device *dev)
992 return sizeof(struct can_device_stats);
995 static int can_fill_xstats(struct sk_buff *skb, const struct net_device *dev)
997 struct can_priv *priv = netdev_priv(dev);
999 if (nla_put(skb, IFLA_INFO_XSTATS,
1000 sizeof(priv->can_stats), &priv->can_stats))
1001 goto nla_put_failure;
1008 static int can_newlink(struct net *src_net, struct net_device *dev,
1009 struct nlattr *tb[], struct nlattr *data[])
1014 static void can_dellink(struct net_device *dev, struct list_head *head)
1019 static struct rtnl_link_ops can_link_ops __read_mostly = {
1021 .maxtype = IFLA_CAN_MAX,
1022 .policy = can_policy,
1024 .validate = can_validate,
1025 .newlink = can_newlink,
1026 .changelink = can_changelink,
1027 .dellink = can_dellink,
1028 .get_size = can_get_size,
1029 .fill_info = can_fill_info,
1030 .get_xstats_size = can_get_xstats_size,
1031 .fill_xstats = can_fill_xstats,
1035 * Register the CAN network device
1037 int register_candev(struct net_device *dev)
1039 dev->rtnl_link_ops = &can_link_ops;
1040 return register_netdev(dev);
1042 EXPORT_SYMBOL_GPL(register_candev);
1045 * Unregister the CAN network device
1047 void unregister_candev(struct net_device *dev)
1049 unregister_netdev(dev);
1051 EXPORT_SYMBOL_GPL(unregister_candev);
1054 * Test if a network device is a candev based device
1055 * and return the can_priv* if so.
1057 struct can_priv *safe_candev_priv(struct net_device *dev)
1059 if ((dev->type != ARPHRD_CAN) || (dev->rtnl_link_ops != &can_link_ops))
1062 return netdev_priv(dev);
1064 EXPORT_SYMBOL_GPL(safe_candev_priv);
1066 static __init int can_dev_init(void)
1070 can_led_notifier_init();
1072 err = rtnl_link_register(&can_link_ops);
1074 printk(KERN_INFO MOD_DESC "\n");
1078 module_init(can_dev_init);
1080 static __exit void can_dev_exit(void)
1082 rtnl_link_unregister(&can_link_ops);
1084 can_led_notifier_exit();
1086 module_exit(can_dev_exit);
1088 MODULE_ALIAS_RTNL_LINK("can");