dev.c revision 2e1143742789463c00ed5e7f9bf471f2b707b493
1/* 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> 5 * 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 9 * 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. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program; if not, write to the Free Software 17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 18 */ 19 20#include <linux/module.h> 21#include <linux/kernel.h> 22#include <linux/slab.h> 23#include <linux/netdevice.h> 24#include <linux/if_arp.h> 25#include <linux/can.h> 26#include <linux/can/dev.h> 27#include <linux/can/netlink.h> 28#include <net/rtnetlink.h> 29 30#define MOD_DESC "CAN device driver interface" 31 32MODULE_DESCRIPTION(MOD_DESC); 33MODULE_LICENSE("GPL v2"); 34MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>"); 35 36#ifdef CONFIG_CAN_CALC_BITTIMING 37#define CAN_CALC_MAX_ERROR 50 /* in one-tenth of a percent */ 38 39/* 40 * Bit-timing calculation derived from: 41 * 42 * Code based on LinCAN sources and H8S2638 project 43 * Copyright 2004-2006 Pavel Pisa - DCE FELK CVUT cz 44 * Copyright 2005 Stanislav Marek 45 * email: pisa@cmp.felk.cvut.cz 46 * 47 * Calculates proper bit-timing parameters for a specified bit-rate 48 * and sample-point, which can then be used to set the bit-timing 49 * registers of the CAN controller. You can find more information 50 * in the header file linux/can/netlink.h. 51 */ 52static int can_update_spt(const struct can_bittiming_const *btc, 53 int sampl_pt, int tseg, int *tseg1, int *tseg2) 54{ 55 *tseg2 = tseg + 1 - (sampl_pt * (tseg + 1)) / 1000; 56 if (*tseg2 < btc->tseg2_min) 57 *tseg2 = btc->tseg2_min; 58 if (*tseg2 > btc->tseg2_max) 59 *tseg2 = btc->tseg2_max; 60 *tseg1 = tseg - *tseg2; 61 if (*tseg1 > btc->tseg1_max) { 62 *tseg1 = btc->tseg1_max; 63 *tseg2 = tseg - *tseg1; 64 } 65 return 1000 * (tseg + 1 - *tseg2) / (tseg + 1); 66} 67 68static int can_calc_bittiming(struct net_device *dev, struct can_bittiming *bt) 69{ 70 struct can_priv *priv = netdev_priv(dev); 71 const struct can_bittiming_const *btc = priv->bittiming_const; 72 long rate, best_rate = 0; 73 long best_error = 1000000000, error = 0; 74 int best_tseg = 0, best_brp = 0, brp = 0; 75 int tsegall, tseg = 0, tseg1 = 0, tseg2 = 0; 76 int spt_error = 1000, spt = 0, sampl_pt; 77 u64 v64; 78 79 if (!priv->bittiming_const) 80 return -ENOTSUPP; 81 82 /* Use CIA recommended sample points */ 83 if (bt->sample_point) { 84 sampl_pt = bt->sample_point; 85 } else { 86 if (bt->bitrate > 800000) 87 sampl_pt = 750; 88 else if (bt->bitrate > 500000) 89 sampl_pt = 800; 90 else 91 sampl_pt = 875; 92 } 93 94 /* tseg even = round down, odd = round up */ 95 for (tseg = (btc->tseg1_max + btc->tseg2_max) * 2 + 1; 96 tseg >= (btc->tseg1_min + btc->tseg2_min) * 2; tseg--) { 97 tsegall = 1 + tseg / 2; 98 /* Compute all possible tseg choices (tseg=tseg1+tseg2) */ 99 brp = priv->clock.freq / (tsegall * bt->bitrate) + tseg % 2; 100 /* chose brp step which is possible in system */ 101 brp = (brp / btc->brp_inc) * btc->brp_inc; 102 if ((brp < btc->brp_min) || (brp > btc->brp_max)) 103 continue; 104 rate = priv->clock.freq / (brp * tsegall); 105 error = bt->bitrate - rate; 106 /* tseg brp biterror */ 107 if (error < 0) 108 error = -error; 109 if (error > best_error) 110 continue; 111 best_error = error; 112 if (error == 0) { 113 spt = can_update_spt(btc, sampl_pt, tseg / 2, 114 &tseg1, &tseg2); 115 error = sampl_pt - spt; 116 if (error < 0) 117 error = -error; 118 if (error > spt_error) 119 continue; 120 spt_error = error; 121 } 122 best_tseg = tseg / 2; 123 best_brp = brp; 124 best_rate = rate; 125 if (error == 0) 126 break; 127 } 128 129 if (best_error) { 130 /* Error in one-tenth of a percent */ 131 error = (best_error * 1000) / bt->bitrate; 132 if (error > CAN_CALC_MAX_ERROR) { 133 dev_err(dev->dev.parent, 134 "bitrate error %ld.%ld%% too high\n", 135 error / 10, error % 10); 136 return -EDOM; 137 } else { 138 dev_warn(dev->dev.parent, "bitrate error %ld.%ld%%\n", 139 error / 10, error % 10); 140 } 141 } 142 143 /* real sample point */ 144 bt->sample_point = can_update_spt(btc, sampl_pt, best_tseg, 145 &tseg1, &tseg2); 146 147 v64 = (u64)best_brp * 1000000000UL; 148 do_div(v64, priv->clock.freq); 149 bt->tq = (u32)v64; 150 bt->prop_seg = tseg1 / 2; 151 bt->phase_seg1 = tseg1 - bt->prop_seg; 152 bt->phase_seg2 = tseg2; 153 154 /* check for sjw user settings */ 155 if (!bt->sjw || !btc->sjw_max) 156 bt->sjw = 1; 157 else { 158 /* bt->sjw is at least 1 -> sanitize upper bound to sjw_max */ 159 if (bt->sjw > btc->sjw_max) 160 bt->sjw = btc->sjw_max; 161 /* bt->sjw must not be higher than tseg2 */ 162 if (tseg2 < bt->sjw) 163 bt->sjw = tseg2; 164 } 165 166 bt->brp = best_brp; 167 /* real bit-rate */ 168 bt->bitrate = priv->clock.freq / (bt->brp * (tseg1 + tseg2 + 1)); 169 170 return 0; 171} 172#else /* !CONFIG_CAN_CALC_BITTIMING */ 173static int can_calc_bittiming(struct net_device *dev, struct can_bittiming *bt) 174{ 175 dev_err(dev->dev.parent, "bit-timing calculation not available\n"); 176 return -EINVAL; 177} 178#endif /* CONFIG_CAN_CALC_BITTIMING */ 179 180/* 181 * Checks the validity of the specified bit-timing parameters prop_seg, 182 * phase_seg1, phase_seg2 and sjw and tries to determine the bitrate 183 * prescaler value brp. You can find more information in the header 184 * file linux/can/netlink.h. 185 */ 186static int can_fixup_bittiming(struct net_device *dev, struct can_bittiming *bt) 187{ 188 struct can_priv *priv = netdev_priv(dev); 189 const struct can_bittiming_const *btc = priv->bittiming_const; 190 int tseg1, alltseg; 191 u64 brp64; 192 193 if (!priv->bittiming_const) 194 return -ENOTSUPP; 195 196 tseg1 = bt->prop_seg + bt->phase_seg1; 197 if (!bt->sjw) 198 bt->sjw = 1; 199 if (bt->sjw > btc->sjw_max || 200 tseg1 < btc->tseg1_min || tseg1 > btc->tseg1_max || 201 bt->phase_seg2 < btc->tseg2_min || bt->phase_seg2 > btc->tseg2_max) 202 return -ERANGE; 203 204 brp64 = (u64)priv->clock.freq * (u64)bt->tq; 205 if (btc->brp_inc > 1) 206 do_div(brp64, btc->brp_inc); 207 brp64 += 500000000UL - 1; 208 do_div(brp64, 1000000000UL); /* the practicable BRP */ 209 if (btc->brp_inc > 1) 210 brp64 *= btc->brp_inc; 211 bt->brp = (u32)brp64; 212 213 if (bt->brp < btc->brp_min || bt->brp > btc->brp_max) 214 return -EINVAL; 215 216 alltseg = bt->prop_seg + bt->phase_seg1 + bt->phase_seg2 + 1; 217 bt->bitrate = priv->clock.freq / (bt->brp * alltseg); 218 bt->sample_point = ((tseg1 + 1) * 1000) / alltseg; 219 220 return 0; 221} 222 223static int can_get_bittiming(struct net_device *dev, struct can_bittiming *bt) 224{ 225 struct can_priv *priv = netdev_priv(dev); 226 int err; 227 228 /* Check if the CAN device has bit-timing parameters */ 229 if (priv->bittiming_const) { 230 231 /* Non-expert mode? Check if the bitrate has been pre-defined */ 232 if (!bt->tq) 233 /* Determine bit-timing parameters */ 234 err = can_calc_bittiming(dev, bt); 235 else 236 /* Check bit-timing params and calculate proper brp */ 237 err = can_fixup_bittiming(dev, bt); 238 if (err) 239 return err; 240 } 241 242 return 0; 243} 244 245/* 246 * Local echo of CAN messages 247 * 248 * CAN network devices *should* support a local echo functionality 249 * (see Documentation/networking/can.txt). To test the handling of CAN 250 * interfaces that do not support the local echo both driver types are 251 * implemented. In the case that the driver does not support the echo 252 * the IFF_ECHO remains clear in dev->flags. This causes the PF_CAN core 253 * to perform the echo as a fallback solution. 254 */ 255static void can_flush_echo_skb(struct net_device *dev) 256{ 257 struct can_priv *priv = netdev_priv(dev); 258 struct net_device_stats *stats = &dev->stats; 259 int i; 260 261 for (i = 0; i < priv->echo_skb_max; i++) { 262 if (priv->echo_skb[i]) { 263 kfree_skb(priv->echo_skb[i]); 264 priv->echo_skb[i] = NULL; 265 stats->tx_dropped++; 266 stats->tx_aborted_errors++; 267 } 268 } 269} 270 271/* 272 * Put the skb on the stack to be looped backed locally lateron 273 * 274 * The function is typically called in the start_xmit function 275 * of the device driver. The driver must protect access to 276 * priv->echo_skb, if necessary. 277 */ 278void can_put_echo_skb(struct sk_buff *skb, struct net_device *dev, 279 unsigned int idx) 280{ 281 struct can_priv *priv = netdev_priv(dev); 282 283 BUG_ON(idx >= priv->echo_skb_max); 284 285 /* check flag whether this packet has to be looped back */ 286 if (!(dev->flags & IFF_ECHO) || skb->pkt_type != PACKET_LOOPBACK) { 287 kfree_skb(skb); 288 return; 289 } 290 291 if (!priv->echo_skb[idx]) { 292 struct sock *srcsk = skb->sk; 293 294 if (atomic_read(&skb->users) != 1) { 295 struct sk_buff *old_skb = skb; 296 297 skb = skb_clone(old_skb, GFP_ATOMIC); 298 kfree_skb(old_skb); 299 if (!skb) 300 return; 301 } else 302 skb_orphan(skb); 303 304 skb->sk = srcsk; 305 306 /* make settings for echo to reduce code in irq context */ 307 skb->protocol = htons(ETH_P_CAN); 308 skb->pkt_type = PACKET_BROADCAST; 309 skb->ip_summed = CHECKSUM_UNNECESSARY; 310 skb->dev = dev; 311 312 /* save this skb for tx interrupt echo handling */ 313 priv->echo_skb[idx] = skb; 314 } else { 315 /* locking problem with netif_stop_queue() ?? */ 316 dev_err(dev->dev.parent, "%s: BUG! echo_skb is occupied!\n", 317 __func__); 318 kfree_skb(skb); 319 } 320} 321EXPORT_SYMBOL_GPL(can_put_echo_skb); 322 323/* 324 * Get the skb from the stack and loop it back locally 325 * 326 * The function is typically called when the TX done interrupt 327 * is handled in the device driver. The driver must protect 328 * access to priv->echo_skb, if necessary. 329 */ 330void can_get_echo_skb(struct net_device *dev, unsigned int idx) 331{ 332 struct can_priv *priv = netdev_priv(dev); 333 334 BUG_ON(idx >= priv->echo_skb_max); 335 336 if (priv->echo_skb[idx]) { 337 netif_rx(priv->echo_skb[idx]); 338 priv->echo_skb[idx] = NULL; 339 } 340} 341EXPORT_SYMBOL_GPL(can_get_echo_skb); 342 343/* 344 * Remove the skb from the stack and free it. 345 * 346 * The function is typically called when TX failed. 347 */ 348void can_free_echo_skb(struct net_device *dev, unsigned int idx) 349{ 350 struct can_priv *priv = netdev_priv(dev); 351 352 BUG_ON(idx >= priv->echo_skb_max); 353 354 if (priv->echo_skb[idx]) { 355 kfree_skb(priv->echo_skb[idx]); 356 priv->echo_skb[idx] = NULL; 357 } 358} 359EXPORT_SYMBOL_GPL(can_free_echo_skb); 360 361/* 362 * CAN device restart for bus-off recovery 363 */ 364void can_restart(unsigned long data) 365{ 366 struct net_device *dev = (struct net_device *)data; 367 struct can_priv *priv = netdev_priv(dev); 368 struct net_device_stats *stats = &dev->stats; 369 struct sk_buff *skb; 370 struct can_frame *cf; 371 int err; 372 373 BUG_ON(netif_carrier_ok(dev)); 374 375 /* 376 * No synchronization needed because the device is bus-off and 377 * no messages can come in or go out. 378 */ 379 can_flush_echo_skb(dev); 380 381 /* send restart message upstream */ 382 skb = alloc_can_err_skb(dev, &cf); 383 if (skb == NULL) { 384 err = -ENOMEM; 385 goto restart; 386 } 387 cf->can_id |= CAN_ERR_RESTARTED; 388 389 netif_rx(skb); 390 391 stats->rx_packets++; 392 stats->rx_bytes += cf->can_dlc; 393 394restart: 395 dev_dbg(dev->dev.parent, "restarted\n"); 396 priv->can_stats.restarts++; 397 398 /* Now restart the device */ 399 err = priv->do_set_mode(dev, CAN_MODE_START); 400 401 netif_carrier_on(dev); 402 if (err) 403 dev_err(dev->dev.parent, "Error %d during restart", err); 404} 405 406int can_restart_now(struct net_device *dev) 407{ 408 struct can_priv *priv = netdev_priv(dev); 409 410 /* 411 * A manual restart is only permitted if automatic restart is 412 * disabled and the device is in the bus-off state 413 */ 414 if (priv->restart_ms) 415 return -EINVAL; 416 if (priv->state != CAN_STATE_BUS_OFF) 417 return -EBUSY; 418 419 /* Runs as soon as possible in the timer context */ 420 mod_timer(&priv->restart_timer, jiffies); 421 422 return 0; 423} 424 425/* 426 * CAN bus-off 427 * 428 * This functions should be called when the device goes bus-off to 429 * tell the netif layer that no more packets can be sent or received. 430 * If enabled, a timer is started to trigger bus-off recovery. 431 */ 432void can_bus_off(struct net_device *dev) 433{ 434 struct can_priv *priv = netdev_priv(dev); 435 436 dev_dbg(dev->dev.parent, "bus-off\n"); 437 438 netif_carrier_off(dev); 439 priv->can_stats.bus_off++; 440 441 if (priv->restart_ms) 442 mod_timer(&priv->restart_timer, 443 jiffies + (priv->restart_ms * HZ) / 1000); 444} 445EXPORT_SYMBOL_GPL(can_bus_off); 446 447static void can_setup(struct net_device *dev) 448{ 449 dev->type = ARPHRD_CAN; 450 dev->mtu = sizeof(struct can_frame); 451 dev->hard_header_len = 0; 452 dev->addr_len = 0; 453 dev->tx_queue_len = 10; 454 455 /* New-style flags. */ 456 dev->flags = IFF_NOARP; 457 dev->features = NETIF_F_NO_CSUM; 458} 459 460struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf) 461{ 462 struct sk_buff *skb; 463 464 skb = netdev_alloc_skb(dev, sizeof(struct can_frame)); 465 if (unlikely(!skb)) 466 return NULL; 467 468 skb->protocol = htons(ETH_P_CAN); 469 skb->pkt_type = PACKET_BROADCAST; 470 skb->ip_summed = CHECKSUM_UNNECESSARY; 471 *cf = (struct can_frame *)skb_put(skb, sizeof(struct can_frame)); 472 memset(*cf, 0, sizeof(struct can_frame)); 473 474 return skb; 475} 476EXPORT_SYMBOL_GPL(alloc_can_skb); 477 478struct sk_buff *alloc_can_err_skb(struct net_device *dev, struct can_frame **cf) 479{ 480 struct sk_buff *skb; 481 482 skb = alloc_can_skb(dev, cf); 483 if (unlikely(!skb)) 484 return NULL; 485 486 (*cf)->can_id = CAN_ERR_FLAG; 487 (*cf)->can_dlc = CAN_ERR_DLC; 488 489 return skb; 490} 491EXPORT_SYMBOL_GPL(alloc_can_err_skb); 492 493/* 494 * Allocate and setup space for the CAN network device 495 */ 496struct net_device *alloc_candev(int sizeof_priv, unsigned int echo_skb_max) 497{ 498 struct net_device *dev; 499 struct can_priv *priv; 500 int size; 501 502 if (echo_skb_max) 503 size = ALIGN(sizeof_priv, sizeof(struct sk_buff *)) + 504 echo_skb_max * sizeof(struct sk_buff *); 505 else 506 size = sizeof_priv; 507 508 dev = alloc_netdev(size, "can%d", can_setup); 509 if (!dev) 510 return NULL; 511 512 priv = netdev_priv(dev); 513 514 if (echo_skb_max) { 515 priv->echo_skb_max = echo_skb_max; 516 priv->echo_skb = (void *)priv + 517 ALIGN(sizeof_priv, sizeof(struct sk_buff *)); 518 } 519 520 priv->state = CAN_STATE_STOPPED; 521 522 init_timer(&priv->restart_timer); 523 524 return dev; 525} 526EXPORT_SYMBOL_GPL(alloc_candev); 527 528/* 529 * Free space of the CAN network device 530 */ 531void free_candev(struct net_device *dev) 532{ 533 free_netdev(dev); 534} 535EXPORT_SYMBOL_GPL(free_candev); 536 537/* 538 * Common open function when the device gets opened. 539 * 540 * This function should be called in the open function of the device 541 * driver. 542 */ 543int open_candev(struct net_device *dev) 544{ 545 struct can_priv *priv = netdev_priv(dev); 546 547 if (!priv->bittiming.tq && !priv->bittiming.bitrate) { 548 dev_err(dev->dev.parent, "bit-timing not yet defined\n"); 549 return -EINVAL; 550 } 551 552 /* Switch carrier on if device was stopped while in bus-off state */ 553 if (!netif_carrier_ok(dev)) 554 netif_carrier_on(dev); 555 556 setup_timer(&priv->restart_timer, can_restart, (unsigned long)dev); 557 558 return 0; 559} 560EXPORT_SYMBOL_GPL(open_candev); 561 562/* 563 * Common close function for cleanup before the device gets closed. 564 * 565 * This function should be called in the close function of the device 566 * driver. 567 */ 568void close_candev(struct net_device *dev) 569{ 570 struct can_priv *priv = netdev_priv(dev); 571 572 if (del_timer_sync(&priv->restart_timer)) 573 dev_put(dev); 574 can_flush_echo_skb(dev); 575} 576EXPORT_SYMBOL_GPL(close_candev); 577 578/* 579 * CAN netlink interface 580 */ 581static const struct nla_policy can_policy[IFLA_CAN_MAX + 1] = { 582 [IFLA_CAN_STATE] = { .type = NLA_U32 }, 583 [IFLA_CAN_CTRLMODE] = { .len = sizeof(struct can_ctrlmode) }, 584 [IFLA_CAN_RESTART_MS] = { .type = NLA_U32 }, 585 [IFLA_CAN_RESTART] = { .type = NLA_U32 }, 586 [IFLA_CAN_BITTIMING] = { .len = sizeof(struct can_bittiming) }, 587 [IFLA_CAN_BITTIMING_CONST] 588 = { .len = sizeof(struct can_bittiming_const) }, 589 [IFLA_CAN_CLOCK] = { .len = sizeof(struct can_clock) }, 590 [IFLA_CAN_BERR_COUNTER] = { .len = sizeof(struct can_berr_counter) }, 591}; 592 593static int can_changelink(struct net_device *dev, 594 struct nlattr *tb[], struct nlattr *data[]) 595{ 596 struct can_priv *priv = netdev_priv(dev); 597 int err; 598 599 /* We need synchronization with dev->stop() */ 600 ASSERT_RTNL(); 601 602 if (data[IFLA_CAN_CTRLMODE]) { 603 struct can_ctrlmode *cm; 604 605 /* Do not allow changing controller mode while running */ 606 if (dev->flags & IFF_UP) 607 return -EBUSY; 608 cm = nla_data(data[IFLA_CAN_CTRLMODE]); 609 if (cm->flags & ~priv->ctrlmode_supported) 610 return -EOPNOTSUPP; 611 priv->ctrlmode &= ~cm->mask; 612 priv->ctrlmode |= cm->flags; 613 } 614 615 if (data[IFLA_CAN_BITTIMING]) { 616 struct can_bittiming bt; 617 618 /* Do not allow changing bittiming while running */ 619 if (dev->flags & IFF_UP) 620 return -EBUSY; 621 memcpy(&bt, nla_data(data[IFLA_CAN_BITTIMING]), sizeof(bt)); 622 if ((!bt.bitrate && !bt.tq) || (bt.bitrate && bt.tq)) 623 return -EINVAL; 624 err = can_get_bittiming(dev, &bt); 625 if (err) 626 return err; 627 memcpy(&priv->bittiming, &bt, sizeof(bt)); 628 629 if (priv->do_set_bittiming) { 630 /* Finally, set the bit-timing registers */ 631 err = priv->do_set_bittiming(dev); 632 if (err) 633 return err; 634 } 635 } 636 637 if (data[IFLA_CAN_RESTART_MS]) { 638 /* Do not allow changing restart delay while running */ 639 if (dev->flags & IFF_UP) 640 return -EBUSY; 641 priv->restart_ms = nla_get_u32(data[IFLA_CAN_RESTART_MS]); 642 } 643 644 if (data[IFLA_CAN_RESTART]) { 645 /* Do not allow a restart while not running */ 646 if (!(dev->flags & IFF_UP)) 647 return -EINVAL; 648 err = can_restart_now(dev); 649 if (err) 650 return err; 651 } 652 653 return 0; 654} 655 656static size_t can_get_size(const struct net_device *dev) 657{ 658 struct can_priv *priv = netdev_priv(dev); 659 size_t size; 660 661 size = nla_total_size(sizeof(u32)); /* IFLA_CAN_STATE */ 662 size += sizeof(struct can_ctrlmode); /* IFLA_CAN_CTRLMODE */ 663 size += nla_total_size(sizeof(u32)); /* IFLA_CAN_RESTART_MS */ 664 size += sizeof(struct can_bittiming); /* IFLA_CAN_BITTIMING */ 665 size += sizeof(struct can_clock); /* IFLA_CAN_CLOCK */ 666 if (priv->do_get_berr_counter) /* IFLA_CAN_BERR_COUNTER */ 667 size += sizeof(struct can_berr_counter); 668 if (priv->bittiming_const) /* IFLA_CAN_BITTIMING_CONST */ 669 size += sizeof(struct can_bittiming_const); 670 671 return size; 672} 673 674static int can_fill_info(struct sk_buff *skb, const struct net_device *dev) 675{ 676 struct can_priv *priv = netdev_priv(dev); 677 struct can_ctrlmode cm = {.flags = priv->ctrlmode}; 678 struct can_berr_counter bec; 679 enum can_state state = priv->state; 680 681 if (priv->do_get_state) 682 priv->do_get_state(dev, &state); 683 NLA_PUT_U32(skb, IFLA_CAN_STATE, state); 684 NLA_PUT(skb, IFLA_CAN_CTRLMODE, sizeof(cm), &cm); 685 NLA_PUT_U32(skb, IFLA_CAN_RESTART_MS, priv->restart_ms); 686 NLA_PUT(skb, IFLA_CAN_BITTIMING, 687 sizeof(priv->bittiming), &priv->bittiming); 688 NLA_PUT(skb, IFLA_CAN_CLOCK, sizeof(cm), &priv->clock); 689 if (priv->do_get_berr_counter && !priv->do_get_berr_counter(dev, &bec)) 690 NLA_PUT(skb, IFLA_CAN_BERR_COUNTER, sizeof(bec), &bec); 691 if (priv->bittiming_const) 692 NLA_PUT(skb, IFLA_CAN_BITTIMING_CONST, 693 sizeof(*priv->bittiming_const), priv->bittiming_const); 694 695 return 0; 696 697nla_put_failure: 698 return -EMSGSIZE; 699} 700 701static size_t can_get_xstats_size(const struct net_device *dev) 702{ 703 return sizeof(struct can_device_stats); 704} 705 706static int can_fill_xstats(struct sk_buff *skb, const struct net_device *dev) 707{ 708 struct can_priv *priv = netdev_priv(dev); 709 710 NLA_PUT(skb, IFLA_INFO_XSTATS, 711 sizeof(priv->can_stats), &priv->can_stats); 712 713 return 0; 714 715nla_put_failure: 716 return -EMSGSIZE; 717} 718 719static int can_newlink(struct net *src_net, struct net_device *dev, 720 struct nlattr *tb[], struct nlattr *data[]) 721{ 722 return -EOPNOTSUPP; 723} 724 725static struct rtnl_link_ops can_link_ops __read_mostly = { 726 .kind = "can", 727 .maxtype = IFLA_CAN_MAX, 728 .policy = can_policy, 729 .setup = can_setup, 730 .newlink = can_newlink, 731 .changelink = can_changelink, 732 .get_size = can_get_size, 733 .fill_info = can_fill_info, 734 .get_xstats_size = can_get_xstats_size, 735 .fill_xstats = can_fill_xstats, 736}; 737 738/* 739 * Register the CAN network device 740 */ 741int register_candev(struct net_device *dev) 742{ 743 dev->rtnl_link_ops = &can_link_ops; 744 return register_netdev(dev); 745} 746EXPORT_SYMBOL_GPL(register_candev); 747 748/* 749 * Unregister the CAN network device 750 */ 751void unregister_candev(struct net_device *dev) 752{ 753 unregister_netdev(dev); 754} 755EXPORT_SYMBOL_GPL(unregister_candev); 756 757static __init int can_dev_init(void) 758{ 759 int err; 760 761 err = rtnl_link_register(&can_link_ops); 762 if (!err) 763 printk(KERN_INFO MOD_DESC "\n"); 764 765 return err; 766} 767module_init(can_dev_init); 768 769static __exit void can_dev_exit(void) 770{ 771 rtnl_link_unregister(&can_link_ops); 772} 773module_exit(can_dev_exit); 774 775MODULE_ALIAS_RTNL_LINK("can"); 776