sja1000.c revision a6e4bc5304033e434fabccabb230b8e9ff55d76f
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 uint8_t dlc; 297 int i; 298 299 skb = dev_alloc_skb(sizeof(struct can_frame)); 300 if (skb == NULL) 301 return; 302 skb->dev = dev; 303 skb->protocol = htons(ETH_P_CAN); 304 305 fi = priv->read_reg(priv, REG_FI); 306 dlc = fi & 0x0F; 307 308 if (fi & FI_FF) { 309 /* extended frame format (EFF) */ 310 dreg = EFF_BUF; 311 id = (priv->read_reg(priv, REG_ID1) << (5 + 16)) 312 | (priv->read_reg(priv, REG_ID2) << (5 + 8)) 313 | (priv->read_reg(priv, REG_ID3) << 5) 314 | (priv->read_reg(priv, REG_ID4) >> 3); 315 id |= CAN_EFF_FLAG; 316 } else { 317 /* standard frame format (SFF) */ 318 dreg = SFF_BUF; 319 id = (priv->read_reg(priv, REG_ID1) << 3) 320 | (priv->read_reg(priv, REG_ID2) >> 5); 321 } 322 323 if (fi & FI_RTR) 324 id |= CAN_RTR_FLAG; 325 326 cf = (struct can_frame *)skb_put(skb, sizeof(struct can_frame)); 327 memset(cf, 0, sizeof(struct can_frame)); 328 cf->can_id = id; 329 cf->can_dlc = dlc; 330 for (i = 0; i < dlc; i++) 331 cf->data[i] = priv->read_reg(priv, dreg++); 332 333 while (i < 8) 334 cf->data[i++] = 0; 335 336 /* release receive buffer */ 337 priv->write_reg(priv, REG_CMR, CMD_RRB); 338 339 netif_rx(skb); 340 341 stats->rx_packets++; 342 stats->rx_bytes += dlc; 343} 344 345static int sja1000_err(struct net_device *dev, uint8_t isrc, uint8_t status) 346{ 347 struct sja1000_priv *priv = netdev_priv(dev); 348 struct net_device_stats *stats = &dev->stats; 349 struct can_frame *cf; 350 struct sk_buff *skb; 351 enum can_state state = priv->can.state; 352 uint8_t ecc, alc; 353 354 skb = dev_alloc_skb(sizeof(struct can_frame)); 355 if (skb == NULL) 356 return -ENOMEM; 357 skb->dev = dev; 358 skb->protocol = htons(ETH_P_CAN); 359 cf = (struct can_frame *)skb_put(skb, sizeof(struct can_frame)); 360 memset(cf, 0, sizeof(struct can_frame)); 361 cf->can_id = CAN_ERR_FLAG; 362 cf->can_dlc = CAN_ERR_DLC; 363 364 if (isrc & IRQ_DOI) { 365 /* data overrun interrupt */ 366 dev_dbg(dev->dev.parent, "data overrun interrupt\n"); 367 cf->can_id |= CAN_ERR_CRTL; 368 cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW; 369 stats->rx_over_errors++; 370 stats->rx_errors++; 371 priv->write_reg(priv, REG_CMR, CMD_CDO); /* clear bit */ 372 } 373 374 if (isrc & IRQ_EI) { 375 /* error warning interrupt */ 376 dev_dbg(dev->dev.parent, "error warning interrupt\n"); 377 378 if (status & SR_BS) { 379 state = CAN_STATE_BUS_OFF; 380 cf->can_id |= CAN_ERR_BUSOFF; 381 can_bus_off(dev); 382 } else if (status & SR_ES) { 383 state = CAN_STATE_ERROR_WARNING; 384 } else 385 state = CAN_STATE_ERROR_ACTIVE; 386 } 387 if (isrc & IRQ_BEI) { 388 /* bus error interrupt */ 389 priv->can.can_stats.bus_error++; 390 stats->rx_errors++; 391 392 ecc = priv->read_reg(priv, REG_ECC); 393 394 cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR; 395 396 switch (ecc & ECC_MASK) { 397 case ECC_BIT: 398 cf->data[2] |= CAN_ERR_PROT_BIT; 399 break; 400 case ECC_FORM: 401 cf->data[2] |= CAN_ERR_PROT_FORM; 402 break; 403 case ECC_STUFF: 404 cf->data[2] |= CAN_ERR_PROT_STUFF; 405 break; 406 default: 407 cf->data[2] |= CAN_ERR_PROT_UNSPEC; 408 cf->data[3] = ecc & ECC_SEG; 409 break; 410 } 411 /* Error occured during transmission? */ 412 if ((ecc & ECC_DIR) == 0) 413 cf->data[2] |= CAN_ERR_PROT_TX; 414 } 415 if (isrc & IRQ_EPI) { 416 /* error passive interrupt */ 417 dev_dbg(dev->dev.parent, "error passive interrupt\n"); 418 if (status & SR_ES) 419 state = CAN_STATE_ERROR_PASSIVE; 420 else 421 state = CAN_STATE_ERROR_ACTIVE; 422 } 423 if (isrc & IRQ_ALI) { 424 /* arbitration lost interrupt */ 425 dev_dbg(dev->dev.parent, "arbitration lost interrupt\n"); 426 alc = priv->read_reg(priv, REG_ALC); 427 priv->can.can_stats.arbitration_lost++; 428 stats->tx_errors++; 429 cf->can_id |= CAN_ERR_LOSTARB; 430 cf->data[0] = alc & 0x1f; 431 } 432 433 if (state != priv->can.state && (state == CAN_STATE_ERROR_WARNING || 434 state == CAN_STATE_ERROR_PASSIVE)) { 435 uint8_t rxerr = priv->read_reg(priv, REG_RXERR); 436 uint8_t txerr = priv->read_reg(priv, REG_TXERR); 437 cf->can_id |= CAN_ERR_CRTL; 438 if (state == CAN_STATE_ERROR_WARNING) { 439 priv->can.can_stats.error_warning++; 440 cf->data[1] = (txerr > rxerr) ? 441 CAN_ERR_CRTL_TX_WARNING : 442 CAN_ERR_CRTL_RX_WARNING; 443 } else { 444 priv->can.can_stats.error_passive++; 445 cf->data[1] = (txerr > rxerr) ? 446 CAN_ERR_CRTL_TX_PASSIVE : 447 CAN_ERR_CRTL_RX_PASSIVE; 448 } 449 } 450 451 priv->can.state = state; 452 453 netif_rx(skb); 454 455 stats->rx_packets++; 456 stats->rx_bytes += cf->can_dlc; 457 458 return 0; 459} 460 461irqreturn_t sja1000_interrupt(int irq, void *dev_id) 462{ 463 struct net_device *dev = (struct net_device *)dev_id; 464 struct sja1000_priv *priv = netdev_priv(dev); 465 struct net_device_stats *stats = &dev->stats; 466 uint8_t isrc, status; 467 int n = 0; 468 469 /* Shared interrupts and IRQ off? */ 470 if (priv->read_reg(priv, REG_IER) == IRQ_OFF) 471 return IRQ_NONE; 472 473 if (priv->pre_irq) 474 priv->pre_irq(priv); 475 476 while ((isrc = priv->read_reg(priv, REG_IR)) && (n < SJA1000_MAX_IRQ)) { 477 n++; 478 status = priv->read_reg(priv, REG_SR); 479 480 if (isrc & IRQ_WUI) 481 dev_warn(dev->dev.parent, "wakeup interrupt\n"); 482 483 if (isrc & IRQ_TI) { 484 /* transmission complete interrupt */ 485 stats->tx_bytes += priv->read_reg(priv, REG_FI) & 0xf; 486 stats->tx_packets++; 487 can_get_echo_skb(dev, 0); 488 netif_wake_queue(dev); 489 } 490 if (isrc & IRQ_RI) { 491 /* receive interrupt */ 492 while (status & SR_RBS) { 493 sja1000_rx(dev); 494 status = priv->read_reg(priv, REG_SR); 495 } 496 } 497 if (isrc & (IRQ_DOI | IRQ_EI | IRQ_BEI | IRQ_EPI | IRQ_ALI)) { 498 /* error interrupt */ 499 if (sja1000_err(dev, isrc, status)) 500 break; 501 } 502 } 503 504 if (priv->post_irq) 505 priv->post_irq(priv); 506 507 if (n >= SJA1000_MAX_IRQ) 508 dev_dbg(dev->dev.parent, "%d messages handled in ISR", n); 509 510 return (n) ? IRQ_HANDLED : IRQ_NONE; 511} 512EXPORT_SYMBOL_GPL(sja1000_interrupt); 513 514static int sja1000_open(struct net_device *dev) 515{ 516 struct sja1000_priv *priv = netdev_priv(dev); 517 int err; 518 519 /* set chip into reset mode */ 520 set_reset_mode(dev); 521 522 /* common open */ 523 err = open_candev(dev); 524 if (err) 525 return err; 526 527 /* register interrupt handler, if not done by the device driver */ 528 if (!(priv->flags & SJA1000_CUSTOM_IRQ_HANDLER)) { 529 err = request_irq(dev->irq, &sja1000_interrupt, priv->irq_flags, 530 dev->name, (void *)dev); 531 if (err) { 532 close_candev(dev); 533 return -EAGAIN; 534 } 535 } 536 537 /* init and start chi */ 538 sja1000_start(dev); 539 priv->open_time = jiffies; 540 541 netif_start_queue(dev); 542 543 return 0; 544} 545 546static int sja1000_close(struct net_device *dev) 547{ 548 struct sja1000_priv *priv = netdev_priv(dev); 549 550 netif_stop_queue(dev); 551 set_reset_mode(dev); 552 553 if (!(priv->flags & SJA1000_CUSTOM_IRQ_HANDLER)) 554 free_irq(dev->irq, (void *)dev); 555 556 close_candev(dev); 557 558 priv->open_time = 0; 559 560 return 0; 561} 562 563struct net_device *alloc_sja1000dev(int sizeof_priv) 564{ 565 struct net_device *dev; 566 struct sja1000_priv *priv; 567 568 dev = alloc_candev(sizeof(struct sja1000_priv) + sizeof_priv, 569 SJA1000_ECHO_SKB_MAX); 570 if (!dev) 571 return NULL; 572 573 priv = netdev_priv(dev); 574 575 priv->dev = dev; 576 priv->can.bittiming_const = &sja1000_bittiming_const; 577 priv->can.do_set_bittiming = sja1000_set_bittiming; 578 priv->can.do_set_mode = sja1000_set_mode; 579 580 if (sizeof_priv) 581 priv->priv = (void *)priv + sizeof(struct sja1000_priv); 582 583 return dev; 584} 585EXPORT_SYMBOL_GPL(alloc_sja1000dev); 586 587void free_sja1000dev(struct net_device *dev) 588{ 589 free_candev(dev); 590} 591EXPORT_SYMBOL_GPL(free_sja1000dev); 592 593static const struct net_device_ops sja1000_netdev_ops = { 594 .ndo_open = sja1000_open, 595 .ndo_stop = sja1000_close, 596 .ndo_start_xmit = sja1000_start_xmit, 597}; 598 599int register_sja1000dev(struct net_device *dev) 600{ 601 if (!sja1000_probe_chip(dev)) 602 return -ENODEV; 603 604 dev->flags |= IFF_ECHO; /* we support local echo */ 605 dev->netdev_ops = &sja1000_netdev_ops; 606 607 set_reset_mode(dev); 608 chipset_init(dev); 609 610 return register_candev(dev); 611} 612EXPORT_SYMBOL_GPL(register_sja1000dev); 613 614void unregister_sja1000dev(struct net_device *dev) 615{ 616 set_reset_mode(dev); 617 unregister_candev(dev); 618} 619EXPORT_SYMBOL_GPL(unregister_sja1000dev); 620 621static __init int sja1000_init(void) 622{ 623 printk(KERN_INFO "%s CAN netdevice driver\n", DRV_NAME); 624 625 return 0; 626} 627 628module_init(sja1000_init); 629 630static __exit void sja1000_exit(void) 631{ 632 printk(KERN_INFO "%s: driver removed\n", DRV_NAME); 633} 634 635module_exit(sja1000_exit); 636