sja1000.c revision 52c793f24054f5dc30d228e37e0e19cc8313f086
1/* 2 * sja1000.c - Philips SJA1000 network device driver 3 * 4 * Copyright (c) 2003 Matthias Brukner, Trajet Gmbh, Rebenring 33, 5 * 38106 Braunschweig, GERMANY 6 * 7 * Copyright (c) 2002-2007 Volkswagen Group Electronic Research 8 * All rights reserved. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of Volkswagen nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * Alternatively, provided that this notice is retained in full, this 23 * software may be distributed under the terms of the GNU General 24 * Public License ("GPL") version 2, in which case the provisions of the 25 * GPL apply INSTEAD OF those given above. 26 * 27 * The provided data structures and external interfaces from this code 28 * are not restricted to be used by modules with a GPL compatible license. 29 * 30 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 31 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 32 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 33 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 34 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 35 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 36 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 37 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 38 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 39 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 40 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH 41 * DAMAGE. 42 * 43 * Send feedback to <socketcan-users@lists.berlios.de> 44 * 45 */ 46 47#include <linux/module.h> 48#include <linux/init.h> 49#include <linux/kernel.h> 50#include <linux/sched.h> 51#include <linux/types.h> 52#include <linux/fcntl.h> 53#include <linux/interrupt.h> 54#include <linux/ptrace.h> 55#include <linux/string.h> 56#include <linux/errno.h> 57#include <linux/netdevice.h> 58#include <linux/if_arp.h> 59#include <linux/if_ether.h> 60#include <linux/skbuff.h> 61#include <linux/delay.h> 62 63#include <linux/can.h> 64#include <linux/can/dev.h> 65#include <linux/can/error.h> 66 67#include "sja1000.h" 68 69#define DRV_NAME "sja1000" 70 71MODULE_AUTHOR("Oliver Hartkopp <oliver.hartkopp@volkswagen.de>"); 72MODULE_LICENSE("Dual BSD/GPL"); 73MODULE_DESCRIPTION(DRV_NAME "CAN netdevice driver"); 74 75static struct can_bittiming_const sja1000_bittiming_const = { 76 .name = DRV_NAME, 77 .tseg1_min = 1, 78 .tseg1_max = 16, 79 .tseg2_min = 1, 80 .tseg2_max = 8, 81 .sjw_max = 4, 82 .brp_min = 1, 83 .brp_max = 64, 84 .brp_inc = 1, 85}; 86 87static int sja1000_probe_chip(struct net_device *dev) 88{ 89 struct sja1000_priv *priv = netdev_priv(dev); 90 91 if (priv->reg_base && (priv->read_reg(priv, 0) == 0xFF)) { 92 printk(KERN_INFO "%s: probing @0x%lX failed\n", 93 DRV_NAME, dev->base_addr); 94 return 0; 95 } 96 return -1; 97} 98 99static void set_reset_mode(struct net_device *dev) 100{ 101 struct sja1000_priv *priv = netdev_priv(dev); 102 unsigned char status = priv->read_reg(priv, REG_MOD); 103 int i; 104 105 /* disable interrupts */ 106 priv->write_reg(priv, REG_IER, IRQ_OFF); 107 108 for (i = 0; i < 100; i++) { 109 /* check reset bit */ 110 if (status & MOD_RM) { 111 priv->can.state = CAN_STATE_STOPPED; 112 return; 113 } 114 115 priv->write_reg(priv, REG_MOD, MOD_RM); /* reset chip */ 116 udelay(10); 117 status = priv->read_reg(priv, REG_MOD); 118 } 119 120 dev_err(dev->dev.parent, "setting SJA1000 into reset mode failed!\n"); 121} 122 123static void set_normal_mode(struct net_device *dev) 124{ 125 struct sja1000_priv *priv = netdev_priv(dev); 126 unsigned char status = priv->read_reg(priv, REG_MOD); 127 int i; 128 129 for (i = 0; i < 100; i++) { 130 /* check reset bit */ 131 if ((status & MOD_RM) == 0) { 132 priv->can.state = CAN_STATE_ERROR_ACTIVE; 133 /* enable interrupts */ 134 if (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING) 135 priv->write_reg(priv, REG_IER, IRQ_ALL); 136 else 137 priv->write_reg(priv, REG_IER, 138 IRQ_ALL & ~IRQ_BEI); 139 return; 140 } 141 142 /* set chip to normal mode */ 143 priv->write_reg(priv, REG_MOD, 0x00); 144 udelay(10); 145 status = priv->read_reg(priv, REG_MOD); 146 } 147 148 dev_err(dev->dev.parent, "setting SJA1000 into normal mode failed!\n"); 149} 150 151static void sja1000_start(struct net_device *dev) 152{ 153 struct sja1000_priv *priv = netdev_priv(dev); 154 155 /* leave reset mode */ 156 if (priv->can.state != CAN_STATE_STOPPED) 157 set_reset_mode(dev); 158 159 /* Clear error counters and error code capture */ 160 priv->write_reg(priv, REG_TXERR, 0x0); 161 priv->write_reg(priv, REG_RXERR, 0x0); 162 priv->read_reg(priv, REG_ECC); 163 164 /* leave reset mode */ 165 set_normal_mode(dev); 166} 167 168static int sja1000_set_mode(struct net_device *dev, enum can_mode mode) 169{ 170 struct sja1000_priv *priv = netdev_priv(dev); 171 172 if (!priv->open_time) 173 return -EINVAL; 174 175 switch (mode) { 176 case CAN_MODE_START: 177 sja1000_start(dev); 178 if (netif_queue_stopped(dev)) 179 netif_wake_queue(dev); 180 break; 181 182 default: 183 return -EOPNOTSUPP; 184 } 185 186 return 0; 187} 188 189static int sja1000_set_bittiming(struct net_device *dev) 190{ 191 struct sja1000_priv *priv = netdev_priv(dev); 192 struct can_bittiming *bt = &priv->can.bittiming; 193 u8 btr0, btr1; 194 195 btr0 = ((bt->brp - 1) & 0x3f) | (((bt->sjw - 1) & 0x3) << 6); 196 btr1 = ((bt->prop_seg + bt->phase_seg1 - 1) & 0xf) | 197 (((bt->phase_seg2 - 1) & 0x7) << 4); 198 if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES) 199 btr1 |= 0x80; 200 201 dev_info(dev->dev.parent, 202 "setting BTR0=0x%02x BTR1=0x%02x\n", btr0, btr1); 203 204 priv->write_reg(priv, REG_BTR0, btr0); 205 priv->write_reg(priv, REG_BTR1, btr1); 206 207 return 0; 208} 209 210static int sja1000_get_berr_counter(const struct net_device *dev, 211 struct can_berr_counter *bec) 212{ 213 struct sja1000_priv *priv = netdev_priv(dev); 214 215 bec->txerr = priv->read_reg(priv, REG_TXERR); 216 bec->rxerr = priv->read_reg(priv, REG_RXERR); 217 218 return 0; 219} 220 221/* 222 * initialize SJA1000 chip: 223 * - reset chip 224 * - set output mode 225 * - set baudrate 226 * - enable interrupts 227 * - start operating mode 228 */ 229static void chipset_init(struct net_device *dev) 230{ 231 struct sja1000_priv *priv = netdev_priv(dev); 232 233 /* set clock divider and output control register */ 234 priv->write_reg(priv, REG_CDR, priv->cdr | CDR_PELICAN); 235 236 /* set acceptance filter (accept all) */ 237 priv->write_reg(priv, REG_ACCC0, 0x00); 238 priv->write_reg(priv, REG_ACCC1, 0x00); 239 priv->write_reg(priv, REG_ACCC2, 0x00); 240 priv->write_reg(priv, REG_ACCC3, 0x00); 241 242 priv->write_reg(priv, REG_ACCM0, 0xFF); 243 priv->write_reg(priv, REG_ACCM1, 0xFF); 244 priv->write_reg(priv, REG_ACCM2, 0xFF); 245 priv->write_reg(priv, REG_ACCM3, 0xFF); 246 247 priv->write_reg(priv, REG_OCR, priv->ocr | OCR_MODE_NORMAL); 248} 249 250/* 251 * transmit a CAN message 252 * message layout in the sk_buff should be like this: 253 * xx xx xx xx ff ll 00 11 22 33 44 55 66 77 254 * [ can-id ] [flags] [len] [can data (up to 8 bytes] 255 */ 256static netdev_tx_t sja1000_start_xmit(struct sk_buff *skb, 257 struct net_device *dev) 258{ 259 struct sja1000_priv *priv = netdev_priv(dev); 260 struct can_frame *cf = (struct can_frame *)skb->data; 261 uint8_t fi; 262 uint8_t dlc; 263 canid_t id; 264 uint8_t dreg; 265 int i; 266 267 if (can_dropped_invalid_skb(dev, skb)) 268 return NETDEV_TX_OK; 269 270 netif_stop_queue(dev); 271 272 fi = dlc = cf->can_dlc; 273 id = cf->can_id; 274 275 if (id & CAN_RTR_FLAG) 276 fi |= FI_RTR; 277 278 if (id & CAN_EFF_FLAG) { 279 fi |= FI_FF; 280 dreg = EFF_BUF; 281 priv->write_reg(priv, REG_FI, fi); 282 priv->write_reg(priv, REG_ID1, (id & 0x1fe00000) >> (5 + 16)); 283 priv->write_reg(priv, REG_ID2, (id & 0x001fe000) >> (5 + 8)); 284 priv->write_reg(priv, REG_ID3, (id & 0x00001fe0) >> 5); 285 priv->write_reg(priv, REG_ID4, (id & 0x0000001f) << 3); 286 } else { 287 dreg = SFF_BUF; 288 priv->write_reg(priv, REG_FI, fi); 289 priv->write_reg(priv, REG_ID1, (id & 0x000007f8) >> 3); 290 priv->write_reg(priv, REG_ID2, (id & 0x00000007) << 5); 291 } 292 293 for (i = 0; i < dlc; i++) 294 priv->write_reg(priv, dreg++, cf->data[i]); 295 296 dev->trans_start = jiffies; 297 298 can_put_echo_skb(skb, dev, 0); 299 300 priv->write_reg(priv, REG_CMR, CMD_TR); 301 302 return NETDEV_TX_OK; 303} 304 305static void sja1000_rx(struct net_device *dev) 306{ 307 struct sja1000_priv *priv = netdev_priv(dev); 308 struct net_device_stats *stats = &dev->stats; 309 struct can_frame *cf; 310 struct sk_buff *skb; 311 uint8_t fi; 312 uint8_t dreg; 313 canid_t id; 314 int i; 315 316 /* create zero'ed CAN frame buffer */ 317 skb = alloc_can_skb(dev, &cf); 318 if (skb == NULL) 319 return; 320 321 fi = priv->read_reg(priv, REG_FI); 322 323 if (fi & FI_FF) { 324 /* extended frame format (EFF) */ 325 dreg = EFF_BUF; 326 id = (priv->read_reg(priv, REG_ID1) << (5 + 16)) 327 | (priv->read_reg(priv, REG_ID2) << (5 + 8)) 328 | (priv->read_reg(priv, REG_ID3) << 5) 329 | (priv->read_reg(priv, REG_ID4) >> 3); 330 id |= CAN_EFF_FLAG; 331 } else { 332 /* standard frame format (SFF) */ 333 dreg = SFF_BUF; 334 id = (priv->read_reg(priv, REG_ID1) << 3) 335 | (priv->read_reg(priv, REG_ID2) >> 5); 336 } 337 338 if (fi & FI_RTR) { 339 id |= CAN_RTR_FLAG; 340 } else { 341 cf->can_dlc = get_can_dlc(fi & 0x0F); 342 for (i = 0; i < cf->can_dlc; i++) 343 cf->data[i] = priv->read_reg(priv, dreg++); 344 } 345 346 cf->can_id = id; 347 348 /* release receive buffer */ 349 priv->write_reg(priv, REG_CMR, CMD_RRB); 350 351 netif_rx(skb); 352 353 stats->rx_packets++; 354 stats->rx_bytes += cf->can_dlc; 355} 356 357static int sja1000_err(struct net_device *dev, uint8_t isrc, uint8_t status) 358{ 359 struct sja1000_priv *priv = netdev_priv(dev); 360 struct net_device_stats *stats = &dev->stats; 361 struct can_frame *cf; 362 struct sk_buff *skb; 363 enum can_state state = priv->can.state; 364 uint8_t ecc, alc; 365 366 skb = alloc_can_err_skb(dev, &cf); 367 if (skb == NULL) 368 return -ENOMEM; 369 370 if (isrc & IRQ_DOI) { 371 /* data overrun interrupt */ 372 dev_dbg(dev->dev.parent, "data overrun interrupt\n"); 373 cf->can_id |= CAN_ERR_CRTL; 374 cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW; 375 stats->rx_over_errors++; 376 stats->rx_errors++; 377 priv->write_reg(priv, REG_CMR, CMD_CDO); /* clear bit */ 378 } 379 380 if (isrc & IRQ_EI) { 381 /* error warning interrupt */ 382 dev_dbg(dev->dev.parent, "error warning interrupt\n"); 383 384 if (status & SR_BS) { 385 state = CAN_STATE_BUS_OFF; 386 cf->can_id |= CAN_ERR_BUSOFF; 387 can_bus_off(dev); 388 } else if (status & SR_ES) { 389 state = CAN_STATE_ERROR_WARNING; 390 } else 391 state = CAN_STATE_ERROR_ACTIVE; 392 } 393 if (isrc & IRQ_BEI) { 394 /* bus error interrupt */ 395 priv->can.can_stats.bus_error++; 396 stats->rx_errors++; 397 398 ecc = priv->read_reg(priv, REG_ECC); 399 400 cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR; 401 402 switch (ecc & ECC_MASK) { 403 case ECC_BIT: 404 cf->data[2] |= CAN_ERR_PROT_BIT; 405 break; 406 case ECC_FORM: 407 cf->data[2] |= CAN_ERR_PROT_FORM; 408 break; 409 case ECC_STUFF: 410 cf->data[2] |= CAN_ERR_PROT_STUFF; 411 break; 412 default: 413 cf->data[2] |= CAN_ERR_PROT_UNSPEC; 414 cf->data[3] = ecc & ECC_SEG; 415 break; 416 } 417 /* Error occured during transmission? */ 418 if ((ecc & ECC_DIR) == 0) 419 cf->data[2] |= CAN_ERR_PROT_TX; 420 } 421 if (isrc & IRQ_EPI) { 422 /* error passive interrupt */ 423 dev_dbg(dev->dev.parent, "error passive interrupt\n"); 424 if (status & SR_ES) 425 state = CAN_STATE_ERROR_PASSIVE; 426 else 427 state = CAN_STATE_ERROR_ACTIVE; 428 } 429 if (isrc & IRQ_ALI) { 430 /* arbitration lost interrupt */ 431 dev_dbg(dev->dev.parent, "arbitration lost interrupt\n"); 432 alc = priv->read_reg(priv, REG_ALC); 433 priv->can.can_stats.arbitration_lost++; 434 stats->tx_errors++; 435 cf->can_id |= CAN_ERR_LOSTARB; 436 cf->data[0] = alc & 0x1f; 437 } 438 439 if (state != priv->can.state && (state == CAN_STATE_ERROR_WARNING || 440 state == CAN_STATE_ERROR_PASSIVE)) { 441 uint8_t rxerr = priv->read_reg(priv, REG_RXERR); 442 uint8_t txerr = priv->read_reg(priv, REG_TXERR); 443 cf->can_id |= CAN_ERR_CRTL; 444 if (state == CAN_STATE_ERROR_WARNING) { 445 priv->can.can_stats.error_warning++; 446 cf->data[1] = (txerr > rxerr) ? 447 CAN_ERR_CRTL_TX_WARNING : 448 CAN_ERR_CRTL_RX_WARNING; 449 } else { 450 priv->can.can_stats.error_passive++; 451 cf->data[1] = (txerr > rxerr) ? 452 CAN_ERR_CRTL_TX_PASSIVE : 453 CAN_ERR_CRTL_RX_PASSIVE; 454 } 455 cf->data[6] = txerr; 456 cf->data[7] = rxerr; 457 } 458 459 priv->can.state = state; 460 461 netif_rx(skb); 462 463 stats->rx_packets++; 464 stats->rx_bytes += cf->can_dlc; 465 466 return 0; 467} 468 469irqreturn_t sja1000_interrupt(int irq, void *dev_id) 470{ 471 struct net_device *dev = (struct net_device *)dev_id; 472 struct sja1000_priv *priv = netdev_priv(dev); 473 struct net_device_stats *stats = &dev->stats; 474 uint8_t isrc, status; 475 int n = 0; 476 477 /* Shared interrupts and IRQ off? */ 478 if (priv->read_reg(priv, REG_IER) == IRQ_OFF) 479 return IRQ_NONE; 480 481 if (priv->pre_irq) 482 priv->pre_irq(priv); 483 484 while ((isrc = priv->read_reg(priv, REG_IR)) && (n < SJA1000_MAX_IRQ)) { 485 n++; 486 status = priv->read_reg(priv, REG_SR); 487 488 if (isrc & IRQ_WUI) 489 dev_warn(dev->dev.parent, "wakeup interrupt\n"); 490 491 if (isrc & IRQ_TI) { 492 /* transmission complete interrupt */ 493 stats->tx_bytes += priv->read_reg(priv, REG_FI) & 0xf; 494 stats->tx_packets++; 495 can_get_echo_skb(dev, 0); 496 netif_wake_queue(dev); 497 } 498 if (isrc & IRQ_RI) { 499 /* receive interrupt */ 500 while (status & SR_RBS) { 501 sja1000_rx(dev); 502 status = priv->read_reg(priv, REG_SR); 503 } 504 } 505 if (isrc & (IRQ_DOI | IRQ_EI | IRQ_BEI | IRQ_EPI | IRQ_ALI)) { 506 /* error interrupt */ 507 if (sja1000_err(dev, isrc, status)) 508 break; 509 } 510 } 511 512 if (priv->post_irq) 513 priv->post_irq(priv); 514 515 if (n >= SJA1000_MAX_IRQ) 516 dev_dbg(dev->dev.parent, "%d messages handled in ISR", n); 517 518 return (n) ? IRQ_HANDLED : IRQ_NONE; 519} 520EXPORT_SYMBOL_GPL(sja1000_interrupt); 521 522static int sja1000_open(struct net_device *dev) 523{ 524 struct sja1000_priv *priv = netdev_priv(dev); 525 int err; 526 527 /* set chip into reset mode */ 528 set_reset_mode(dev); 529 530 /* common open */ 531 err = open_candev(dev); 532 if (err) 533 return err; 534 535 /* register interrupt handler, if not done by the device driver */ 536 if (!(priv->flags & SJA1000_CUSTOM_IRQ_HANDLER)) { 537 err = request_irq(dev->irq, sja1000_interrupt, priv->irq_flags, 538 dev->name, (void *)dev); 539 if (err) { 540 close_candev(dev); 541 return -EAGAIN; 542 } 543 } 544 545 /* init and start chi */ 546 sja1000_start(dev); 547 priv->open_time = jiffies; 548 549 netif_start_queue(dev); 550 551 return 0; 552} 553 554static int sja1000_close(struct net_device *dev) 555{ 556 struct sja1000_priv *priv = netdev_priv(dev); 557 558 netif_stop_queue(dev); 559 set_reset_mode(dev); 560 561 if (!(priv->flags & SJA1000_CUSTOM_IRQ_HANDLER)) 562 free_irq(dev->irq, (void *)dev); 563 564 close_candev(dev); 565 566 priv->open_time = 0; 567 568 return 0; 569} 570 571struct net_device *alloc_sja1000dev(int sizeof_priv) 572{ 573 struct net_device *dev; 574 struct sja1000_priv *priv; 575 576 dev = alloc_candev(sizeof(struct sja1000_priv) + sizeof_priv, 577 SJA1000_ECHO_SKB_MAX); 578 if (!dev) 579 return NULL; 580 581 priv = netdev_priv(dev); 582 583 priv->dev = dev; 584 priv->can.bittiming_const = &sja1000_bittiming_const; 585 priv->can.do_set_bittiming = sja1000_set_bittiming; 586 priv->can.do_set_mode = sja1000_set_mode; 587 priv->can.do_get_berr_counter = sja1000_get_berr_counter; 588 priv->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES | 589 CAN_CTRLMODE_BERR_REPORTING; 590 591 if (sizeof_priv) 592 priv->priv = (void *)priv + sizeof(struct sja1000_priv); 593 594 return dev; 595} 596EXPORT_SYMBOL_GPL(alloc_sja1000dev); 597 598void free_sja1000dev(struct net_device *dev) 599{ 600 free_candev(dev); 601} 602EXPORT_SYMBOL_GPL(free_sja1000dev); 603 604static const struct net_device_ops sja1000_netdev_ops = { 605 .ndo_open = sja1000_open, 606 .ndo_stop = sja1000_close, 607 .ndo_start_xmit = sja1000_start_xmit, 608}; 609 610int register_sja1000dev(struct net_device *dev) 611{ 612 if (!sja1000_probe_chip(dev)) 613 return -ENODEV; 614 615 dev->flags |= IFF_ECHO; /* we support local echo */ 616 dev->netdev_ops = &sja1000_netdev_ops; 617 618 set_reset_mode(dev); 619 chipset_init(dev); 620 621 return register_candev(dev); 622} 623EXPORT_SYMBOL_GPL(register_sja1000dev); 624 625void unregister_sja1000dev(struct net_device *dev) 626{ 627 set_reset_mode(dev); 628 unregister_candev(dev); 629} 630EXPORT_SYMBOL_GPL(unregister_sja1000dev); 631 632static __init int sja1000_init(void) 633{ 634 printk(KERN_INFO "%s CAN netdevice driver\n", DRV_NAME); 635 636 return 0; 637} 638 639module_init(sja1000_init); 640 641static __exit void sja1000_exit(void) 642{ 643 printk(KERN_INFO "%s: driver removed\n", DRV_NAME); 644} 645 646module_exit(sja1000_exit); 647