sja1000.c revision 829e0015431537176e38812f88fffe1d3250083e
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/dev.h> 64#include <linux/can/error.h> 65 66#include "sja1000.h" 67 68#define DRV_NAME "sja1000" 69 70MODULE_AUTHOR("Oliver Hartkopp <oliver.hartkopp@volkswagen.de>"); 71MODULE_LICENSE("Dual BSD/GPL"); 72MODULE_DESCRIPTION(DRV_NAME "CAN netdevice driver"); 73 74static struct can_bittiming_const sja1000_bittiming_const = { 75 .name = DRV_NAME, 76 .tseg1_min = 1, 77 .tseg1_max = 16, 78 .tseg2_min = 1, 79 .tseg2_max = 8, 80 .sjw_max = 4, 81 .brp_min = 1, 82 .brp_max = 64, 83 .brp_inc = 1, 84}; 85 86static int sja1000_probe_chip(struct net_device *dev) 87{ 88 struct sja1000_priv *priv = netdev_priv(dev); 89 90 if (priv->reg_base && (priv->read_reg(priv, 0) == 0xFF)) { 91 printk(KERN_INFO "%s: probing @0x%lX failed\n", 92 DRV_NAME, dev->base_addr); 93 return 0; 94 } 95 return -1; 96} 97 98static void set_reset_mode(struct net_device *dev) 99{ 100 struct sja1000_priv *priv = netdev_priv(dev); 101 unsigned char status = priv->read_reg(priv, REG_MOD); 102 int i; 103 104 /* disable interrupts */ 105 priv->write_reg(priv, REG_IER, IRQ_OFF); 106 107 for (i = 0; i < 100; i++) { 108 /* check reset bit */ 109 if (status & MOD_RM) { 110 priv->can.state = CAN_STATE_STOPPED; 111 return; 112 } 113 114 priv->write_reg(priv, REG_MOD, MOD_RM); /* reset chip */ 115 udelay(10); 116 status = priv->read_reg(priv, REG_MOD); 117 } 118 119 dev_err(dev->dev.parent, "setting SJA1000 into reset mode failed!\n"); 120} 121 122static void set_normal_mode(struct net_device *dev) 123{ 124 struct sja1000_priv *priv = netdev_priv(dev); 125 unsigned char status = priv->read_reg(priv, REG_MOD); 126 int i; 127 128 for (i = 0; i < 100; i++) { 129 /* check reset bit */ 130 if ((status & MOD_RM) == 0) { 131 priv->can.state = CAN_STATE_ERROR_ACTIVE; 132 /* enable interrupts */ 133 if (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING) 134 priv->write_reg(priv, REG_IER, IRQ_ALL); 135 else 136 priv->write_reg(priv, REG_IER, 137 IRQ_ALL & ~IRQ_BEI); 138 return; 139 } 140 141 /* set chip to normal mode */ 142 priv->write_reg(priv, REG_MOD, 0x00); 143 udelay(10); 144 status = priv->read_reg(priv, REG_MOD); 145 } 146 147 dev_err(dev->dev.parent, "setting SJA1000 into normal mode failed!\n"); 148} 149 150static void sja1000_start(struct net_device *dev) 151{ 152 struct sja1000_priv *priv = netdev_priv(dev); 153 154 /* leave reset mode */ 155 if (priv->can.state != CAN_STATE_STOPPED) 156 set_reset_mode(dev); 157 158 /* Clear error counters and error code capture */ 159 priv->write_reg(priv, REG_TXERR, 0x0); 160 priv->write_reg(priv, REG_RXERR, 0x0); 161 priv->read_reg(priv, REG_ECC); 162 163 /* leave reset mode */ 164 set_normal_mode(dev); 165} 166 167static int sja1000_set_mode(struct net_device *dev, enum can_mode mode) 168{ 169 struct sja1000_priv *priv = netdev_priv(dev); 170 171 if (!priv->open_time) 172 return -EINVAL; 173 174 switch (mode) { 175 case CAN_MODE_START: 176 sja1000_start(dev); 177 if (netif_queue_stopped(dev)) 178 netif_wake_queue(dev); 179 break; 180 181 default: 182 return -EOPNOTSUPP; 183 } 184 185 return 0; 186} 187 188static int sja1000_set_bittiming(struct net_device *dev) 189{ 190 struct sja1000_priv *priv = netdev_priv(dev); 191 struct can_bittiming *bt = &priv->can.bittiming; 192 u8 btr0, btr1; 193 194 btr0 = ((bt->brp - 1) & 0x3f) | (((bt->sjw - 1) & 0x3) << 6); 195 btr1 = ((bt->prop_seg + bt->phase_seg1 - 1) & 0xf) | 196 (((bt->phase_seg2 - 1) & 0x7) << 4); 197 if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES) 198 btr1 |= 0x80; 199 200 dev_info(dev->dev.parent, 201 "setting BTR0=0x%02x BTR1=0x%02x\n", btr0, btr1); 202 203 priv->write_reg(priv, REG_BTR0, btr0); 204 priv->write_reg(priv, REG_BTR1, btr1); 205 206 return 0; 207} 208 209static int sja1000_get_berr_counter(const struct net_device *dev, 210 struct can_berr_counter *bec) 211{ 212 struct sja1000_priv *priv = netdev_priv(dev); 213 214 bec->txerr = priv->read_reg(priv, REG_TXERR); 215 bec->rxerr = priv->read_reg(priv, REG_RXERR); 216 217 return 0; 218} 219 220/* 221 * initialize SJA1000 chip: 222 * - reset chip 223 * - set output mode 224 * - set baudrate 225 * - enable interrupts 226 * - start operating mode 227 */ 228static void chipset_init(struct net_device *dev) 229{ 230 struct sja1000_priv *priv = netdev_priv(dev); 231 232 /* set clock divider and output control register */ 233 priv->write_reg(priv, REG_CDR, priv->cdr | CDR_PELICAN); 234 235 /* set acceptance filter (accept all) */ 236 priv->write_reg(priv, REG_ACCC0, 0x00); 237 priv->write_reg(priv, REG_ACCC1, 0x00); 238 priv->write_reg(priv, REG_ACCC2, 0x00); 239 priv->write_reg(priv, REG_ACCC3, 0x00); 240 241 priv->write_reg(priv, REG_ACCM0, 0xFF); 242 priv->write_reg(priv, REG_ACCM1, 0xFF); 243 priv->write_reg(priv, REG_ACCM2, 0xFF); 244 priv->write_reg(priv, REG_ACCM3, 0xFF); 245 246 priv->write_reg(priv, REG_OCR, priv->ocr | OCR_MODE_NORMAL); 247} 248 249/* 250 * transmit a CAN message 251 * message layout in the sk_buff should be like this: 252 * xx xx xx xx ff ll 00 11 22 33 44 55 66 77 253 * [ can-id ] [flags] [len] [can data (up to 8 bytes] 254 */ 255static netdev_tx_t sja1000_start_xmit(struct sk_buff *skb, 256 struct net_device *dev) 257{ 258 struct sja1000_priv *priv = netdev_priv(dev); 259 struct can_frame *cf = (struct can_frame *)skb->data; 260 uint8_t fi; 261 uint8_t dlc; 262 canid_t id; 263 uint8_t dreg; 264 int i; 265 266 if (can_dropped_invalid_skb(dev, skb)) 267 return NETDEV_TX_OK; 268 269 netif_stop_queue(dev); 270 271 fi = dlc = cf->can_dlc; 272 id = cf->can_id; 273 274 if (id & CAN_RTR_FLAG) 275 fi |= FI_RTR; 276 277 if (id & CAN_EFF_FLAG) { 278 fi |= FI_FF; 279 dreg = EFF_BUF; 280 priv->write_reg(priv, REG_FI, fi); 281 priv->write_reg(priv, REG_ID1, (id & 0x1fe00000) >> (5 + 16)); 282 priv->write_reg(priv, REG_ID2, (id & 0x001fe000) >> (5 + 8)); 283 priv->write_reg(priv, REG_ID3, (id & 0x00001fe0) >> 5); 284 priv->write_reg(priv, REG_ID4, (id & 0x0000001f) << 3); 285 } else { 286 dreg = SFF_BUF; 287 priv->write_reg(priv, REG_FI, fi); 288 priv->write_reg(priv, REG_ID1, (id & 0x000007f8) >> 3); 289 priv->write_reg(priv, REG_ID2, (id & 0x00000007) << 5); 290 } 291 292 for (i = 0; i < dlc; i++) 293 priv->write_reg(priv, dreg++, cf->data[i]); 294 295 dev->trans_start = jiffies; 296 297 can_put_echo_skb(skb, dev, 0); 298 299 priv->write_reg(priv, REG_CMR, CMD_TR); 300 301 return NETDEV_TX_OK; 302} 303 304static void sja1000_rx(struct net_device *dev) 305{ 306 struct sja1000_priv *priv = netdev_priv(dev); 307 struct net_device_stats *stats = &dev->stats; 308 struct can_frame *cf; 309 struct sk_buff *skb; 310 uint8_t fi; 311 uint8_t dreg; 312 canid_t id; 313 int i; 314 315 /* create zero'ed CAN frame buffer */ 316 skb = alloc_can_skb(dev, &cf); 317 if (skb == NULL) 318 return; 319 320 fi = priv->read_reg(priv, REG_FI); 321 322 if (fi & FI_FF) { 323 /* extended frame format (EFF) */ 324 dreg = EFF_BUF; 325 id = (priv->read_reg(priv, REG_ID1) << (5 + 16)) 326 | (priv->read_reg(priv, REG_ID2) << (5 + 8)) 327 | (priv->read_reg(priv, REG_ID3) << 5) 328 | (priv->read_reg(priv, REG_ID4) >> 3); 329 id |= CAN_EFF_FLAG; 330 } else { 331 /* standard frame format (SFF) */ 332 dreg = SFF_BUF; 333 id = (priv->read_reg(priv, REG_ID1) << 3) 334 | (priv->read_reg(priv, REG_ID2) >> 5); 335 } 336 337 if (fi & FI_RTR) { 338 id |= CAN_RTR_FLAG; 339 } else { 340 cf->can_dlc = get_can_dlc(fi & 0x0F); 341 for (i = 0; i < cf->can_dlc; i++) 342 cf->data[i] = priv->read_reg(priv, dreg++); 343 } 344 345 cf->can_id = id; 346 347 /* release receive buffer */ 348 priv->write_reg(priv, REG_CMR, CMD_RRB); 349 350 netif_rx(skb); 351 352 stats->rx_packets++; 353 stats->rx_bytes += cf->can_dlc; 354} 355 356static int sja1000_err(struct net_device *dev, uint8_t isrc, uint8_t status) 357{ 358 struct sja1000_priv *priv = netdev_priv(dev); 359 struct net_device_stats *stats = &dev->stats; 360 struct can_frame *cf; 361 struct sk_buff *skb; 362 enum can_state state = priv->can.state; 363 uint8_t ecc, alc; 364 365 skb = alloc_can_err_skb(dev, &cf); 366 if (skb == NULL) 367 return -ENOMEM; 368 369 if (isrc & IRQ_DOI) { 370 /* data overrun interrupt */ 371 dev_dbg(dev->dev.parent, "data overrun interrupt\n"); 372 cf->can_id |= CAN_ERR_CRTL; 373 cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW; 374 stats->rx_over_errors++; 375 stats->rx_errors++; 376 priv->write_reg(priv, REG_CMR, CMD_CDO); /* clear bit */ 377 } 378 379 if (isrc & IRQ_EI) { 380 /* error warning interrupt */ 381 dev_dbg(dev->dev.parent, "error warning interrupt\n"); 382 383 if (status & SR_BS) { 384 state = CAN_STATE_BUS_OFF; 385 cf->can_id |= CAN_ERR_BUSOFF; 386 can_bus_off(dev); 387 } else if (status & SR_ES) { 388 state = CAN_STATE_ERROR_WARNING; 389 } else 390 state = CAN_STATE_ERROR_ACTIVE; 391 } 392 if (isrc & IRQ_BEI) { 393 /* bus error interrupt */ 394 priv->can.can_stats.bus_error++; 395 stats->rx_errors++; 396 397 ecc = priv->read_reg(priv, REG_ECC); 398 399 cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR; 400 401 switch (ecc & ECC_MASK) { 402 case ECC_BIT: 403 cf->data[2] |= CAN_ERR_PROT_BIT; 404 break; 405 case ECC_FORM: 406 cf->data[2] |= CAN_ERR_PROT_FORM; 407 break; 408 case ECC_STUFF: 409 cf->data[2] |= CAN_ERR_PROT_STUFF; 410 break; 411 default: 412 cf->data[2] |= CAN_ERR_PROT_UNSPEC; 413 cf->data[3] = ecc & ECC_SEG; 414 break; 415 } 416 /* Error occured during transmission? */ 417 if ((ecc & ECC_DIR) == 0) 418 cf->data[2] |= CAN_ERR_PROT_TX; 419 } 420 if (isrc & IRQ_EPI) { 421 /* error passive interrupt */ 422 dev_dbg(dev->dev.parent, "error passive interrupt\n"); 423 if (status & SR_ES) 424 state = CAN_STATE_ERROR_PASSIVE; 425 else 426 state = CAN_STATE_ERROR_ACTIVE; 427 } 428 if (isrc & IRQ_ALI) { 429 /* arbitration lost interrupt */ 430 dev_dbg(dev->dev.parent, "arbitration lost interrupt\n"); 431 alc = priv->read_reg(priv, REG_ALC); 432 priv->can.can_stats.arbitration_lost++; 433 stats->tx_errors++; 434 cf->can_id |= CAN_ERR_LOSTARB; 435 cf->data[0] = alc & 0x1f; 436 } 437 438 if (state != priv->can.state && (state == CAN_STATE_ERROR_WARNING || 439 state == CAN_STATE_ERROR_PASSIVE)) { 440 uint8_t rxerr = priv->read_reg(priv, REG_RXERR); 441 uint8_t txerr = priv->read_reg(priv, REG_TXERR); 442 cf->can_id |= CAN_ERR_CRTL; 443 if (state == CAN_STATE_ERROR_WARNING) { 444 priv->can.can_stats.error_warning++; 445 cf->data[1] = (txerr > rxerr) ? 446 CAN_ERR_CRTL_TX_WARNING : 447 CAN_ERR_CRTL_RX_WARNING; 448 } else { 449 priv->can.can_stats.error_passive++; 450 cf->data[1] = (txerr > rxerr) ? 451 CAN_ERR_CRTL_TX_PASSIVE : 452 CAN_ERR_CRTL_RX_PASSIVE; 453 } 454 cf->data[6] = txerr; 455 cf->data[7] = rxerr; 456 } 457 458 priv->can.state = state; 459 460 netif_rx(skb); 461 462 stats->rx_packets++; 463 stats->rx_bytes += cf->can_dlc; 464 465 return 0; 466} 467 468irqreturn_t sja1000_interrupt(int irq, void *dev_id) 469{ 470 struct net_device *dev = (struct net_device *)dev_id; 471 struct sja1000_priv *priv = netdev_priv(dev); 472 struct net_device_stats *stats = &dev->stats; 473 uint8_t isrc, status; 474 int n = 0; 475 476 /* Shared interrupts and IRQ off? */ 477 if (priv->read_reg(priv, REG_IER) == IRQ_OFF) 478 return IRQ_NONE; 479 480 if (priv->pre_irq) 481 priv->pre_irq(priv); 482 483 while ((isrc = priv->read_reg(priv, REG_IR)) && (n < SJA1000_MAX_IRQ)) { 484 n++; 485 status = priv->read_reg(priv, REG_SR); 486 487 if (isrc & IRQ_WUI) 488 dev_warn(dev->dev.parent, "wakeup interrupt\n"); 489 490 if (isrc & IRQ_TI) { 491 /* transmission complete interrupt */ 492 stats->tx_bytes += priv->read_reg(priv, REG_FI) & 0xf; 493 stats->tx_packets++; 494 can_get_echo_skb(dev, 0); 495 netif_wake_queue(dev); 496 } 497 if (isrc & IRQ_RI) { 498 /* receive interrupt */ 499 while (status & SR_RBS) { 500 sja1000_rx(dev); 501 status = priv->read_reg(priv, REG_SR); 502 } 503 } 504 if (isrc & (IRQ_DOI | IRQ_EI | IRQ_BEI | IRQ_EPI | IRQ_ALI)) { 505 /* error interrupt */ 506 if (sja1000_err(dev, isrc, status)) 507 break; 508 } 509 } 510 511 if (priv->post_irq) 512 priv->post_irq(priv); 513 514 if (n >= SJA1000_MAX_IRQ) 515 dev_dbg(dev->dev.parent, "%d messages handled in ISR", n); 516 517 return (n) ? IRQ_HANDLED : IRQ_NONE; 518} 519EXPORT_SYMBOL_GPL(sja1000_interrupt); 520 521static int sja1000_open(struct net_device *dev) 522{ 523 struct sja1000_priv *priv = netdev_priv(dev); 524 int err; 525 526 /* set chip into reset mode */ 527 set_reset_mode(dev); 528 529 /* common open */ 530 err = open_candev(dev); 531 if (err) 532 return err; 533 534 /* register interrupt handler, if not done by the device driver */ 535 if (!(priv->flags & SJA1000_CUSTOM_IRQ_HANDLER)) { 536 err = request_irq(dev->irq, sja1000_interrupt, priv->irq_flags, 537 dev->name, (void *)dev); 538 if (err) { 539 close_candev(dev); 540 return -EAGAIN; 541 } 542 } 543 544 /* init and start chi */ 545 sja1000_start(dev); 546 priv->open_time = jiffies; 547 548 netif_start_queue(dev); 549 550 return 0; 551} 552 553static int sja1000_close(struct net_device *dev) 554{ 555 struct sja1000_priv *priv = netdev_priv(dev); 556 557 netif_stop_queue(dev); 558 set_reset_mode(dev); 559 560 if (!(priv->flags & SJA1000_CUSTOM_IRQ_HANDLER)) 561 free_irq(dev->irq, (void *)dev); 562 563 close_candev(dev); 564 565 priv->open_time = 0; 566 567 return 0; 568} 569 570struct net_device *alloc_sja1000dev(int sizeof_priv) 571{ 572 struct net_device *dev; 573 struct sja1000_priv *priv; 574 575 dev = alloc_candev(sizeof(struct sja1000_priv) + sizeof_priv, 576 SJA1000_ECHO_SKB_MAX); 577 if (!dev) 578 return NULL; 579 580 priv = netdev_priv(dev); 581 582 priv->dev = dev; 583 priv->can.bittiming_const = &sja1000_bittiming_const; 584 priv->can.do_set_bittiming = sja1000_set_bittiming; 585 priv->can.do_set_mode = sja1000_set_mode; 586 priv->can.do_get_berr_counter = sja1000_get_berr_counter; 587 priv->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES | 588 CAN_CTRLMODE_BERR_REPORTING; 589 590 if (sizeof_priv) 591 priv->priv = (void *)priv + sizeof(struct sja1000_priv); 592 593 return dev; 594} 595EXPORT_SYMBOL_GPL(alloc_sja1000dev); 596 597void free_sja1000dev(struct net_device *dev) 598{ 599 free_candev(dev); 600} 601EXPORT_SYMBOL_GPL(free_sja1000dev); 602 603static const struct net_device_ops sja1000_netdev_ops = { 604 .ndo_open = sja1000_open, 605 .ndo_stop = sja1000_close, 606 .ndo_start_xmit = sja1000_start_xmit, 607}; 608 609int register_sja1000dev(struct net_device *dev) 610{ 611 if (!sja1000_probe_chip(dev)) 612 return -ENODEV; 613 614 dev->flags |= IFF_ECHO; /* we support local echo */ 615 dev->netdev_ops = &sja1000_netdev_ops; 616 617 set_reset_mode(dev); 618 chipset_init(dev); 619 620 return register_candev(dev); 621} 622EXPORT_SYMBOL_GPL(register_sja1000dev); 623 624void unregister_sja1000dev(struct net_device *dev) 625{ 626 set_reset_mode(dev); 627 unregister_candev(dev); 628} 629EXPORT_SYMBOL_GPL(unregister_sja1000dev); 630 631static __init int sja1000_init(void) 632{ 633 printk(KERN_INFO "%s CAN netdevice driver\n", DRV_NAME); 634 635 return 0; 636} 637 638module_init(sja1000_init); 639 640static __exit void sja1000_exit(void) 641{ 642 printk(KERN_INFO "%s: driver removed\n", DRV_NAME); 643} 644 645module_exit(sja1000_exit); 646