sja1000.c revision c7cd606f60e7679c7f9eee7010f02a6f000209c1
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 all interrupts */ 134 priv->write_reg(priv, REG_IER, IRQ_ALL); 135 return; 136 } 137 138 /* set chip to normal mode */ 139 priv->write_reg(priv, REG_MOD, 0x00); 140 udelay(10); 141 status = priv->read_reg(priv, REG_MOD); 142 } 143 144 dev_err(dev->dev.parent, "setting SJA1000 into normal mode failed!\n"); 145} 146 147static void sja1000_start(struct net_device *dev) 148{ 149 struct sja1000_priv *priv = netdev_priv(dev); 150 151 /* leave reset mode */ 152 if (priv->can.state != CAN_STATE_STOPPED) 153 set_reset_mode(dev); 154 155 /* Clear error counters and error code capture */ 156 priv->write_reg(priv, REG_TXERR, 0x0); 157 priv->write_reg(priv, REG_RXERR, 0x0); 158 priv->read_reg(priv, REG_ECC); 159 160 /* leave reset mode */ 161 set_normal_mode(dev); 162} 163 164static int sja1000_set_mode(struct net_device *dev, enum can_mode mode) 165{ 166 struct sja1000_priv *priv = netdev_priv(dev); 167 168 if (!priv->open_time) 169 return -EINVAL; 170 171 switch (mode) { 172 case CAN_MODE_START: 173 sja1000_start(dev); 174 if (netif_queue_stopped(dev)) 175 netif_wake_queue(dev); 176 break; 177 178 default: 179 return -EOPNOTSUPP; 180 } 181 182 return 0; 183} 184 185static int sja1000_set_bittiming(struct net_device *dev) 186{ 187 struct sja1000_priv *priv = netdev_priv(dev); 188 struct can_bittiming *bt = &priv->can.bittiming; 189 u8 btr0, btr1; 190 191 btr0 = ((bt->brp - 1) & 0x3f) | (((bt->sjw - 1) & 0x3) << 6); 192 btr1 = ((bt->prop_seg + bt->phase_seg1 - 1) & 0xf) | 193 (((bt->phase_seg2 - 1) & 0x7) << 4); 194 if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES) 195 btr1 |= 0x80; 196 197 dev_info(dev->dev.parent, 198 "setting BTR0=0x%02x BTR1=0x%02x\n", btr0, btr1); 199 200 priv->write_reg(priv, REG_BTR0, btr0); 201 priv->write_reg(priv, REG_BTR1, btr1); 202 203 return 0; 204} 205 206/* 207 * initialize SJA1000 chip: 208 * - reset chip 209 * - set output mode 210 * - set baudrate 211 * - enable interrupts 212 * - start operating mode 213 */ 214static void chipset_init(struct net_device *dev) 215{ 216 struct sja1000_priv *priv = netdev_priv(dev); 217 218 /* set clock divider and output control register */ 219 priv->write_reg(priv, REG_CDR, priv->cdr | CDR_PELICAN); 220 221 /* set acceptance filter (accept all) */ 222 priv->write_reg(priv, REG_ACCC0, 0x00); 223 priv->write_reg(priv, REG_ACCC1, 0x00); 224 priv->write_reg(priv, REG_ACCC2, 0x00); 225 priv->write_reg(priv, REG_ACCC3, 0x00); 226 227 priv->write_reg(priv, REG_ACCM0, 0xFF); 228 priv->write_reg(priv, REG_ACCM1, 0xFF); 229 priv->write_reg(priv, REG_ACCM2, 0xFF); 230 priv->write_reg(priv, REG_ACCM3, 0xFF); 231 232 priv->write_reg(priv, REG_OCR, priv->ocr | OCR_MODE_NORMAL); 233} 234 235/* 236 * transmit a CAN message 237 * message layout in the sk_buff should be like this: 238 * xx xx xx xx ff ll 00 11 22 33 44 55 66 77 239 * [ can-id ] [flags] [len] [can data (up to 8 bytes] 240 */ 241static netdev_tx_t sja1000_start_xmit(struct sk_buff *skb, 242 struct net_device *dev) 243{ 244 struct sja1000_priv *priv = netdev_priv(dev); 245 struct can_frame *cf = (struct can_frame *)skb->data; 246 uint8_t fi; 247 uint8_t dlc; 248 canid_t id; 249 uint8_t dreg; 250 int i; 251 252 netif_stop_queue(dev); 253 254 fi = dlc = cf->can_dlc; 255 id = cf->can_id; 256 257 if (id & CAN_RTR_FLAG) 258 fi |= FI_RTR; 259 260 if (id & CAN_EFF_FLAG) { 261 fi |= FI_FF; 262 dreg = EFF_BUF; 263 priv->write_reg(priv, REG_FI, fi); 264 priv->write_reg(priv, REG_ID1, (id & 0x1fe00000) >> (5 + 16)); 265 priv->write_reg(priv, REG_ID2, (id & 0x001fe000) >> (5 + 8)); 266 priv->write_reg(priv, REG_ID3, (id & 0x00001fe0) >> 5); 267 priv->write_reg(priv, REG_ID4, (id & 0x0000001f) << 3); 268 } else { 269 dreg = SFF_BUF; 270 priv->write_reg(priv, REG_FI, fi); 271 priv->write_reg(priv, REG_ID1, (id & 0x000007f8) >> 3); 272 priv->write_reg(priv, REG_ID2, (id & 0x00000007) << 5); 273 } 274 275 for (i = 0; i < dlc; i++) 276 priv->write_reg(priv, dreg++, cf->data[i]); 277 278 dev->trans_start = jiffies; 279 280 can_put_echo_skb(skb, dev, 0); 281 282 priv->write_reg(priv, REG_CMR, CMD_TR); 283 284 return NETDEV_TX_OK; 285} 286 287static void sja1000_rx(struct net_device *dev) 288{ 289 struct sja1000_priv *priv = netdev_priv(dev); 290 struct net_device_stats *stats = &dev->stats; 291 struct can_frame *cf; 292 struct sk_buff *skb; 293 uint8_t fi; 294 uint8_t dreg; 295 canid_t id; 296 int i; 297 298 /* create zero'ed CAN frame buffer */ 299 skb = alloc_can_skb(dev, &cf); 300 if (skb == NULL) 301 return; 302 303 fi = priv->read_reg(priv, REG_FI); 304 305 if (fi & FI_FF) { 306 /* extended frame format (EFF) */ 307 dreg = EFF_BUF; 308 id = (priv->read_reg(priv, REG_ID1) << (5 + 16)) 309 | (priv->read_reg(priv, REG_ID2) << (5 + 8)) 310 | (priv->read_reg(priv, REG_ID3) << 5) 311 | (priv->read_reg(priv, REG_ID4) >> 3); 312 id |= CAN_EFF_FLAG; 313 } else { 314 /* standard frame format (SFF) */ 315 dreg = SFF_BUF; 316 id = (priv->read_reg(priv, REG_ID1) << 3) 317 | (priv->read_reg(priv, REG_ID2) >> 5); 318 } 319 320 if (fi & FI_RTR) { 321 id |= CAN_RTR_FLAG; 322 } else { 323 cf->can_dlc = get_can_dlc(fi & 0x0F); 324 for (i = 0; i < cf->can_dlc; i++) 325 cf->data[i] = priv->read_reg(priv, dreg++); 326 } 327 328 cf->can_id = id; 329 330 /* release receive buffer */ 331 priv->write_reg(priv, REG_CMR, CMD_RRB); 332 333 netif_rx(skb); 334 335 stats->rx_packets++; 336 stats->rx_bytes += cf->can_dlc; 337} 338 339static int sja1000_err(struct net_device *dev, uint8_t isrc, uint8_t status) 340{ 341 struct sja1000_priv *priv = netdev_priv(dev); 342 struct net_device_stats *stats = &dev->stats; 343 struct can_frame *cf; 344 struct sk_buff *skb; 345 enum can_state state = priv->can.state; 346 uint8_t ecc, alc; 347 348 skb = alloc_can_err_skb(dev, &cf); 349 if (skb == NULL) 350 return -ENOMEM; 351 352 if (isrc & IRQ_DOI) { 353 /* data overrun interrupt */ 354 dev_dbg(dev->dev.parent, "data overrun interrupt\n"); 355 cf->can_id |= CAN_ERR_CRTL; 356 cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW; 357 stats->rx_over_errors++; 358 stats->rx_errors++; 359 priv->write_reg(priv, REG_CMR, CMD_CDO); /* clear bit */ 360 } 361 362 if (isrc & IRQ_EI) { 363 /* error warning interrupt */ 364 dev_dbg(dev->dev.parent, "error warning interrupt\n"); 365 366 if (status & SR_BS) { 367 state = CAN_STATE_BUS_OFF; 368 cf->can_id |= CAN_ERR_BUSOFF; 369 can_bus_off(dev); 370 } else if (status & SR_ES) { 371 state = CAN_STATE_ERROR_WARNING; 372 } else 373 state = CAN_STATE_ERROR_ACTIVE; 374 } 375 if (isrc & IRQ_BEI) { 376 /* bus error interrupt */ 377 priv->can.can_stats.bus_error++; 378 stats->rx_errors++; 379 380 ecc = priv->read_reg(priv, REG_ECC); 381 382 cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR; 383 384 switch (ecc & ECC_MASK) { 385 case ECC_BIT: 386 cf->data[2] |= CAN_ERR_PROT_BIT; 387 break; 388 case ECC_FORM: 389 cf->data[2] |= CAN_ERR_PROT_FORM; 390 break; 391 case ECC_STUFF: 392 cf->data[2] |= CAN_ERR_PROT_STUFF; 393 break; 394 default: 395 cf->data[2] |= CAN_ERR_PROT_UNSPEC; 396 cf->data[3] = ecc & ECC_SEG; 397 break; 398 } 399 /* Error occured during transmission? */ 400 if ((ecc & ECC_DIR) == 0) 401 cf->data[2] |= CAN_ERR_PROT_TX; 402 } 403 if (isrc & IRQ_EPI) { 404 /* error passive interrupt */ 405 dev_dbg(dev->dev.parent, "error passive interrupt\n"); 406 if (status & SR_ES) 407 state = CAN_STATE_ERROR_PASSIVE; 408 else 409 state = CAN_STATE_ERROR_ACTIVE; 410 } 411 if (isrc & IRQ_ALI) { 412 /* arbitration lost interrupt */ 413 dev_dbg(dev->dev.parent, "arbitration lost interrupt\n"); 414 alc = priv->read_reg(priv, REG_ALC); 415 priv->can.can_stats.arbitration_lost++; 416 stats->tx_errors++; 417 cf->can_id |= CAN_ERR_LOSTARB; 418 cf->data[0] = alc & 0x1f; 419 } 420 421 if (state != priv->can.state && (state == CAN_STATE_ERROR_WARNING || 422 state == CAN_STATE_ERROR_PASSIVE)) { 423 uint8_t rxerr = priv->read_reg(priv, REG_RXERR); 424 uint8_t txerr = priv->read_reg(priv, REG_TXERR); 425 cf->can_id |= CAN_ERR_CRTL; 426 if (state == CAN_STATE_ERROR_WARNING) { 427 priv->can.can_stats.error_warning++; 428 cf->data[1] = (txerr > rxerr) ? 429 CAN_ERR_CRTL_TX_WARNING : 430 CAN_ERR_CRTL_RX_WARNING; 431 } else { 432 priv->can.can_stats.error_passive++; 433 cf->data[1] = (txerr > rxerr) ? 434 CAN_ERR_CRTL_TX_PASSIVE : 435 CAN_ERR_CRTL_RX_PASSIVE; 436 } 437 } 438 439 priv->can.state = state; 440 441 netif_rx(skb); 442 443 stats->rx_packets++; 444 stats->rx_bytes += cf->can_dlc; 445 446 return 0; 447} 448 449irqreturn_t sja1000_interrupt(int irq, void *dev_id) 450{ 451 struct net_device *dev = (struct net_device *)dev_id; 452 struct sja1000_priv *priv = netdev_priv(dev); 453 struct net_device_stats *stats = &dev->stats; 454 uint8_t isrc, status; 455 int n = 0; 456 457 /* Shared interrupts and IRQ off? */ 458 if (priv->read_reg(priv, REG_IER) == IRQ_OFF) 459 return IRQ_NONE; 460 461 if (priv->pre_irq) 462 priv->pre_irq(priv); 463 464 while ((isrc = priv->read_reg(priv, REG_IR)) && (n < SJA1000_MAX_IRQ)) { 465 n++; 466 status = priv->read_reg(priv, REG_SR); 467 468 if (isrc & IRQ_WUI) 469 dev_warn(dev->dev.parent, "wakeup interrupt\n"); 470 471 if (isrc & IRQ_TI) { 472 /* transmission complete interrupt */ 473 stats->tx_bytes += priv->read_reg(priv, REG_FI) & 0xf; 474 stats->tx_packets++; 475 can_get_echo_skb(dev, 0); 476 netif_wake_queue(dev); 477 } 478 if (isrc & IRQ_RI) { 479 /* receive interrupt */ 480 while (status & SR_RBS) { 481 sja1000_rx(dev); 482 status = priv->read_reg(priv, REG_SR); 483 } 484 } 485 if (isrc & (IRQ_DOI | IRQ_EI | IRQ_BEI | IRQ_EPI | IRQ_ALI)) { 486 /* error interrupt */ 487 if (sja1000_err(dev, isrc, status)) 488 break; 489 } 490 } 491 492 if (priv->post_irq) 493 priv->post_irq(priv); 494 495 if (n >= SJA1000_MAX_IRQ) 496 dev_dbg(dev->dev.parent, "%d messages handled in ISR", n); 497 498 return (n) ? IRQ_HANDLED : IRQ_NONE; 499} 500EXPORT_SYMBOL_GPL(sja1000_interrupt); 501 502static int sja1000_open(struct net_device *dev) 503{ 504 struct sja1000_priv *priv = netdev_priv(dev); 505 int err; 506 507 /* set chip into reset mode */ 508 set_reset_mode(dev); 509 510 /* common open */ 511 err = open_candev(dev); 512 if (err) 513 return err; 514 515 /* register interrupt handler, if not done by the device driver */ 516 if (!(priv->flags & SJA1000_CUSTOM_IRQ_HANDLER)) { 517 err = request_irq(dev->irq, sja1000_interrupt, priv->irq_flags, 518 dev->name, (void *)dev); 519 if (err) { 520 close_candev(dev); 521 return -EAGAIN; 522 } 523 } 524 525 /* init and start chi */ 526 sja1000_start(dev); 527 priv->open_time = jiffies; 528 529 netif_start_queue(dev); 530 531 return 0; 532} 533 534static int sja1000_close(struct net_device *dev) 535{ 536 struct sja1000_priv *priv = netdev_priv(dev); 537 538 netif_stop_queue(dev); 539 set_reset_mode(dev); 540 541 if (!(priv->flags & SJA1000_CUSTOM_IRQ_HANDLER)) 542 free_irq(dev->irq, (void *)dev); 543 544 close_candev(dev); 545 546 priv->open_time = 0; 547 548 return 0; 549} 550 551struct net_device *alloc_sja1000dev(int sizeof_priv) 552{ 553 struct net_device *dev; 554 struct sja1000_priv *priv; 555 556 dev = alloc_candev(sizeof(struct sja1000_priv) + sizeof_priv, 557 SJA1000_ECHO_SKB_MAX); 558 if (!dev) 559 return NULL; 560 561 priv = netdev_priv(dev); 562 563 priv->dev = dev; 564 priv->can.bittiming_const = &sja1000_bittiming_const; 565 priv->can.do_set_bittiming = sja1000_set_bittiming; 566 priv->can.do_set_mode = sja1000_set_mode; 567 568 if (sizeof_priv) 569 priv->priv = (void *)priv + sizeof(struct sja1000_priv); 570 571 return dev; 572} 573EXPORT_SYMBOL_GPL(alloc_sja1000dev); 574 575void free_sja1000dev(struct net_device *dev) 576{ 577 free_candev(dev); 578} 579EXPORT_SYMBOL_GPL(free_sja1000dev); 580 581static const struct net_device_ops sja1000_netdev_ops = { 582 .ndo_open = sja1000_open, 583 .ndo_stop = sja1000_close, 584 .ndo_start_xmit = sja1000_start_xmit, 585}; 586 587int register_sja1000dev(struct net_device *dev) 588{ 589 if (!sja1000_probe_chip(dev)) 590 return -ENODEV; 591 592 dev->flags |= IFF_ECHO; /* we support local echo */ 593 dev->netdev_ops = &sja1000_netdev_ops; 594 595 set_reset_mode(dev); 596 chipset_init(dev); 597 598 return register_candev(dev); 599} 600EXPORT_SYMBOL_GPL(register_sja1000dev); 601 602void unregister_sja1000dev(struct net_device *dev) 603{ 604 set_reset_mode(dev); 605 unregister_candev(dev); 606} 607EXPORT_SYMBOL_GPL(unregister_sja1000dev); 608 609static __init int sja1000_init(void) 610{ 611 printk(KERN_INFO "%s CAN netdevice driver\n", DRV_NAME); 612 613 return 0; 614} 615 616module_init(sja1000_init); 617 618static __exit void sja1000_exit(void) 619{ 620 printk(KERN_INFO "%s: driver removed\n", DRV_NAME); 621} 622 623module_exit(sja1000_exit); 624