drivers/net/can/sja1000/sja1000.c

   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  */
  44
  45 #include <linux/module.h>
  46 #include <linux/init.h>
  47 #include <linux/kernel.h>
  48 #include <linux/sched.h>
  49 #include <linux/types.h>
  50 #include <linux/fcntl.h>
  51 #include <linux/interrupt.h>
  52 #include <linux/ptrace.h>
  53 #include <linux/string.h>
  54 #include <linux/errno.h>
  55 #include <linux/ethtool.h>
  56 #include <linux/netdevice.h>
  57 #include <linux/if_arp.h>
  58 #include <linux/if_ether.h>
  59 #include <linux/skbuff.h>
  60 #include <linux/delay.h>
  61
  62 #include <linux/can/dev.h>
  63 #include <linux/can/error.h>
  64
  65 #include "sja1000.h"
  66
  67 #define DRV_NAME "sja1000"
  68
  69 MODULE_AUTHOR("Oliver Hartkopp <[email protected]>");
  70 MODULE_LICENSE("Dual BSD/GPL");
  71 MODULE_DESCRIPTION(DRV_NAME "CAN netdevice driver");
  72
  73 static const struct can_bittiming_const sja1000_bittiming_const = {
  74         .name = DRV_NAME,
  75         .tseg1_min = 1,
  76         .tseg1_max = 16,
  77         .tseg2_min = 1,
  78         .tseg2_max = 8,
  79         .sjw_max = 4,
  80         .brp_min = 1,
  81         .brp_max = 64,
  82         .brp_inc = 1,
  83 };
  84
  85 static void sja1000_write_cmdreg(struct sja1000_priv *priv, u8 val)
  86 {
  87         unsigned long flags;
  88
  89         /*
  90          * The command register needs some locking and time to settle
  91          * the write_reg() operation - especially on SMP systems.
  92          */
  93         spin_lock_irqsave(&priv->cmdreg_lock, flags);
  94         priv->write_reg(priv, SJA1000_CMR, val);
  95         priv->read_reg(priv, SJA1000_SR);
  96         spin_unlock_irqrestore(&priv->cmdreg_lock, flags);
  97 }
  98
  99 static int sja1000_is_absent(struct sja1000_priv *priv)
 100 {
 101         return (priv->read_reg(priv, SJA1000_MOD) == 0xFF);
 102 }
 103
 104 static int sja1000_probe_chip(struct net_device *dev)
 105 {
 106         struct sja1000_priv *priv = netdev_priv(dev);
 107
 108         if (priv->reg_base && sja1000_is_absent(priv)) {
 109                 netdev_err(dev, "probing failed\n");
 110                 return 0;
 111         }
 112         return -1;
 113 }
 114
 115 static void set_reset_mode(struct net_device *dev)
 116 {
 117         struct sja1000_priv *priv = netdev_priv(dev);
 118         unsigned char status = priv->read_reg(priv, SJA1000_MOD);
 119         int i;
 120
 121         /* disable interrupts */
 122         priv->write_reg(priv, SJA1000_IER, IRQ_OFF);
 123
 124         for (i = 0; i < 100; i++) {
 125                 /* check reset bit */
 126                 if (status & MOD_RM) {
 127                         priv->can.state = CAN_STATE_STOPPED;
 128                         return;
 129                 }
 130
 131                 /* reset chip */
 132                 priv->write_reg(priv, SJA1000_MOD, MOD_RM);
 133                 udelay(10);
 134                 status = priv->read_reg(priv, SJA1000_MOD);
 135         }
 136
 137         netdev_err(dev, "setting SJA1000 into reset mode failed!\n");
 138 }
 139
 140 static void set_normal_mode(struct net_device *dev)
 141 {
 142         struct sja1000_priv *priv = netdev_priv(dev);
 143         unsigned char status = priv->read_reg(priv, SJA1000_MOD);
 144         u8 mod_reg_val = 0x00;
 145         int i;
 146
 147         for (i = 0; i < 100; i++) {
 148                 /* check reset bit */
 149                 if ((status & MOD_RM) == 0) {
 150                         priv->can.state = CAN_STATE_ERROR_ACTIVE;
 151                         /* enable interrupts */
 152                         if (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING)
 153                                 priv->write_reg(priv, SJA1000_IER, IRQ_ALL);
 154                         else
 155                                 priv->write_reg(priv, SJA1000_IER,
 156                                                 IRQ_ALL & ~IRQ_BEI);
 157                         return;
 158                 }
 159
 160                 /* set chip to normal mode */
 161                 if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
 162                         mod_reg_val |= MOD_LOM;
 163                 if (priv->can.ctrlmode & CAN_CTRLMODE_PRESUME_ACK)
 164                         mod_reg_val |= MOD_STM;
 165                 priv->write_reg(priv, SJA1000_MOD, mod_reg_val);
 166
 167                 udelay(10);
 168
 169                 status = priv->read_reg(priv, SJA1000_MOD);
 170         }
 171
 172         netdev_err(dev, "setting SJA1000 into normal mode failed!\n");
 173 }
 174
 175 /*
 176  * initialize SJA1000 chip:
 177  *   - reset chip
 178  *   - set output mode
 179  *   - set baudrate
 180  *   - enable interrupts
 181  *   - start operating mode
 182  */
 183 static void chipset_init(struct net_device *dev)
 184 {
 185         struct sja1000_priv *priv = netdev_priv(dev);
 186
 187         if (!(priv->flags & SJA1000_QUIRK_NO_CDR_REG))
 188                 /* set clock divider and output control register */
 189                 priv->write_reg(priv, SJA1000_CDR, priv->cdr | CDR_PELICAN);
 190
 191         /* set acceptance filter (accept all) */
 192         priv->write_reg(priv, SJA1000_ACCC0, 0x00);
 193         priv->write_reg(priv, SJA1000_ACCC1, 0x00);
 194         priv->write_reg(priv, SJA1000_ACCC2, 0x00);
 195         priv->write_reg(priv, SJA1000_ACCC3, 0x00);
 196
 197         priv->write_reg(priv, SJA1000_ACCM0, 0xFF);
 198         priv->write_reg(priv, SJA1000_ACCM1, 0xFF);
 199         priv->write_reg(priv, SJA1000_ACCM2, 0xFF);
 200         priv->write_reg(priv, SJA1000_ACCM3, 0xFF);
 201
 202         priv->write_reg(priv, SJA1000_OCR, priv->ocr | OCR_MODE_NORMAL);
 203 }
 204
 205 static void sja1000_start(struct net_device *dev)
 206 {
 207         struct sja1000_priv *priv = netdev_priv(dev);
 208
 209         /* enter reset mode */
 210         if (priv->can.state != CAN_STATE_STOPPED)
 211                 set_reset_mode(dev);
 212
 213         /* Initialize chip if uninitialized at this stage */
 214         if (!(priv->flags & SJA1000_QUIRK_NO_CDR_REG ||
 215               priv->read_reg(priv, SJA1000_CDR) & CDR_PELICAN))
 216                 chipset_init(dev);
 217
 218         /* Clear error counters and error code capture */
 219         priv->write_reg(priv, SJA1000_TXERR, 0x0);
 220         priv->write_reg(priv, SJA1000_RXERR, 0x0);
 221         priv->read_reg(priv, SJA1000_ECC);
 222
 223         /* clear interrupt flags */
 224         priv->read_reg(priv, SJA1000_IR);
 225
 226         /* leave reset mode */
 227         set_normal_mode(dev);
 228 }
 229
 230 static int sja1000_set_mode(struct net_device *dev, enum can_mode mode)
 231 {
 232         switch (mode) {
 233         case CAN_MODE_START:
 234                 sja1000_start(dev);
 235                 if (netif_queue_stopped(dev))
 236                         netif_wake_queue(dev);
 237                 break;
 238
 239         default:
 240                 return -EOPNOTSUPP;
 241         }
 242
 243         return 0;
 244 }
 245
 246 static int sja1000_set_bittiming(struct net_device *dev)
 247 {
 248         struct sja1000_priv *priv = netdev_priv(dev);
 249         struct can_bittiming *bt = &priv->can.bittiming;
 250         u8 btr0, btr1;
 251
 252         btr0 = ((bt->brp - 1) & 0x3f) | (((bt->sjw - 1) & 0x3) << 6);
 253         btr1 = ((bt->prop_seg + bt->phase_seg1 - 1) & 0xf) |
 254                 (((bt->phase_seg2 - 1) & 0x7) << 4);
 255         if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
 256                 btr1 |= 0x80;
 257
 258         netdev_info(dev, "setting BTR0=0x%02x BTR1=0x%02x\n", btr0, btr1);
 259
 260         priv->write_reg(priv, SJA1000_BTR0, btr0);
 261         priv->write_reg(priv, SJA1000_BTR1, btr1);
 262
 263         return 0;
 264 }
 265
 266 static int sja1000_get_berr_counter(const struct net_device *dev,
 267                                     struct can_berr_counter *bec)
 268 {
 269         struct sja1000_priv *priv = netdev_priv(dev);
 270
 271         bec->txerr = priv->read_reg(priv, SJA1000_TXERR);
 272         bec->rxerr = priv->read_reg(priv, SJA1000_RXERR);
 273
 274         return 0;
 275 }
 276
 277 /*
 278  * transmit a CAN message
 279  * message layout in the sk_buff should be like this:
 280  * xx xx xx xx   ff      ll   00 11 22 33 44 55 66 77
 281  * [  can-id ] [flags] [len] [can data (up to 8 bytes]
 282  */
 283 static netdev_tx_t sja1000_start_xmit(struct sk_buff *skb,
 284                                             struct net_device *dev)
 285 {
 286         struct sja1000_priv *priv = netdev_priv(dev);
 287         struct can_frame *cf = (struct can_frame *)skb->data;
 288         uint8_t fi;
 289         canid_t id;
 290         uint8_t dreg;
 291         u8 cmd_reg_val = 0x00;
 292         int i;
 293
 294         if (can_dev_dropped_skb(dev, skb))
 295                 return NETDEV_TX_OK;
 296
 297         netif_stop_queue(dev);
 298
 299         fi = can_get_cc_dlc(cf, priv->can.ctrlmode);
 300         id = cf->can_id;
 301
 302         if (id & CAN_RTR_FLAG)
 303                 fi |= SJA1000_FI_RTR;
 304
 305         if (id & CAN_EFF_FLAG) {
 306                 fi |= SJA1000_FI_FF;
 307                 dreg = SJA1000_EFF_BUF;
 308                 priv->write_reg(priv, SJA1000_FI, fi);
 309                 priv->write_reg(priv, SJA1000_ID1, (id & 0x1fe00000) >> 21);
 310                 priv->write_reg(priv, SJA1000_ID2, (id & 0x001fe000) >> 13);
 311                 priv->write_reg(priv, SJA1000_ID3, (id & 0x00001fe0) >> 5);
 312                 priv->write_reg(priv, SJA1000_ID4, (id & 0x0000001f) << 3);
 313         } else {
 314                 dreg = SJA1000_SFF_BUF;
 315                 priv->write_reg(priv, SJA1000_FI, fi);
 316                 priv->write_reg(priv, SJA1000_ID1, (id & 0x000007f8) >> 3);
 317                 priv->write_reg(priv, SJA1000_ID2, (id & 0x00000007) << 5);
 318         }
 319
 320         for (i = 0; i < cf->len; i++)
 321                 priv->write_reg(priv, dreg++, cf->data[i]);
 322
 323         can_put_echo_skb(skb, dev, 0, 0);
 324
 325         if (priv->can.ctrlmode & CAN_CTRLMODE_ONE_SHOT)
 326                 cmd_reg_val |= CMD_AT;
 327
 328         if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
 329                 cmd_reg_val |= CMD_SRR;
 330         else
 331                 cmd_reg_val |= CMD_TR;
 332
 333         sja1000_write_cmdreg(priv, cmd_reg_val);
 334
 335         return NETDEV_TX_OK;
 336 }
 337
 338 static void sja1000_rx(struct net_device *dev)
 339 {
 340         struct sja1000_priv *priv = netdev_priv(dev);
 341         struct net_device_stats *stats = &dev->stats;
 342         struct can_frame *cf;
 343         struct sk_buff *skb;
 344         uint8_t fi;
 345         uint8_t dreg;
 346         canid_t id;
 347         int i;
 348
 349         /* create zero'ed CAN frame buffer */
 350         skb = alloc_can_skb(dev, &cf);
 351         if (skb == NULL)
 352                 return;
 353
 354         fi = priv->read_reg(priv, SJA1000_FI);
 355
 356         if (fi & SJA1000_FI_FF) {
 357                 /* extended frame format (EFF) */
 358                 dreg = SJA1000_EFF_BUF;
 359                 id = (priv->read_reg(priv, SJA1000_ID1) << 21)
 360                     | (priv->read_reg(priv, SJA1000_ID2) << 13)
 361                     | (priv->read_reg(priv, SJA1000_ID3) << 5)
 362                     | (priv->read_reg(priv, SJA1000_ID4) >> 3);
 363                 id |= CAN_EFF_FLAG;
 364         } else {
 365                 /* standard frame format (SFF) */
 366                 dreg = SJA1000_SFF_BUF;
 367                 id = (priv->read_reg(priv, SJA1000_ID1) << 3)
 368                     | (priv->read_reg(priv, SJA1000_ID2) >> 5);
 369         }
 370
 371         can_frame_set_cc_len(cf, fi & 0x0F, priv->can.ctrlmode);
 372         if (fi & SJA1000_FI_RTR) {
 373                 id |= CAN_RTR_FLAG;
 374         } else {
 375                 for (i = 0; i < cf->len; i++)
 376                         cf->data[i] = priv->read_reg(priv, dreg++);
 377
 378                 stats->rx_bytes += cf->len;
 379         }
 380         stats->rx_packets++;
 381
 382         cf->can_id = id;
 383
 384         /* release receive buffer */
 385         sja1000_write_cmdreg(priv, CMD_RRB);
 386
 387         netif_rx(skb);
 388 }
 389
 390 static irqreturn_t sja1000_reset_interrupt(int irq, void *dev_id)
 391 {
 392         struct net_device *dev = (struct net_device *)dev_id;
 393
 394         netdev_dbg(dev, "performing a soft reset upon overrun\n");
 395
 396         netif_tx_lock(dev);
 397
 398         can_free_echo_skb(dev, 0, NULL);
 399         sja1000_set_mode(dev, CAN_MODE_START);
 400
 401         netif_tx_unlock(dev);
 402
 403         return IRQ_HANDLED;
 404 }
 405
 406 static int sja1000_err(struct net_device *dev, uint8_t isrc, uint8_t status)
 407 {
 408         struct sja1000_priv *priv = netdev_priv(dev);
 409         struct net_device_stats *stats = &dev->stats;
 410         struct can_frame *cf;
 411         struct sk_buff *skb;
 412         enum can_state state = priv->can.state;
 413         enum can_state rx_state, tx_state;
 414         unsigned int rxerr, txerr;
 415         uint8_t ecc, alc;
 416         int ret = 0;
 417
 418         skb = alloc_can_err_skb(dev, &cf);
 419
 420         txerr = priv->read_reg(priv, SJA1000_TXERR);
 421         rxerr = priv->read_reg(priv, SJA1000_RXERR);
 422
 423         if (isrc & IRQ_DOI) {
 424                 /* data overrun interrupt */
 425                 netdev_dbg(dev, "data overrun interrupt\n");
 426                 if (skb) {
 427                         cf->can_id |= CAN_ERR_CRTL;
 428                         cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
 429                 }
 430
 431                 stats->rx_over_errors++;
 432                 stats->rx_errors++;
 433                 sja1000_write_cmdreg(priv, CMD_CDO);    /* clear bit */
 434
 435                 /* Some controllers needs additional handling upon overrun
 436                  * condition: the controller may sometimes be totally confused
 437                  * and refuse any new frame while its buffer is empty. The only
 438                  * way to re-sync the read vs. write buffer offsets is to
 439                  * stop any current handling and perform a reset.
 440                  */
 441                 if (priv->flags & SJA1000_QUIRK_RESET_ON_OVERRUN)
 442                         ret = IRQ_WAKE_THREAD;
 443         }
 444
 445         if (isrc & IRQ_EI) {
 446                 /* error warning interrupt */
 447                 netdev_dbg(dev, "error warning interrupt\n");
 448
 449                 if (status & SR_BS)
 450                         state = CAN_STATE_BUS_OFF;
 451                 else if (status & SR_ES)
 452                         state = CAN_STATE_ERROR_WARNING;
 453                 else
 454                         state = CAN_STATE_ERROR_ACTIVE;
 455         }
 456         if (state != CAN_STATE_BUS_OFF && skb) {
 457                 cf->can_id |= CAN_ERR_CNT;
 458                 cf->data[6] = txerr;
 459                 cf->data[7] = rxerr;
 460         }
 461         if (isrc & IRQ_BEI) {
 462                 /* bus error interrupt */
 463                 priv->can.can_stats.bus_error++;
 464
 465                 ecc = priv->read_reg(priv, SJA1000_ECC);
 466                 if (skb) {
 467                         cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
 468
 469                         /* set error type */
 470                         switch (ecc & ECC_MASK) {
 471                         case ECC_BIT:
 472                                 cf->data[2] |= CAN_ERR_PROT_BIT;
 473                                 break;
 474                         case ECC_FORM:
 475                                 cf->data[2] |= CAN_ERR_PROT_FORM;
 476                                 break;
 477                         case ECC_STUFF:
 478                                 cf->data[2] |= CAN_ERR_PROT_STUFF;
 479                                 break;
 480                         default:
 481                                 break;
 482                         }
 483
 484                         /* set error location */
 485                         cf->data[3] = ecc & ECC_SEG;
 486                 }
 487
 488                 /* Error occurred during transmission? */
 489                 if ((ecc & ECC_DIR) == 0) {
 490                         stats->tx_errors++;
 491                         if (skb)
 492                                 cf->data[2] |= CAN_ERR_PROT_TX;
 493                 } else {
 494                         stats->rx_errors++;
 495                 }
 496         }
 497         if (isrc & IRQ_EPI) {
 498                 /* error passive interrupt */
 499                 netdev_dbg(dev, "error passive interrupt\n");
 500
 501                 if (state == CAN_STATE_ERROR_PASSIVE)
 502                         state = CAN_STATE_ERROR_WARNING;
 503                 else
 504                         state = CAN_STATE_ERROR_PASSIVE;
 505         }
 506         if (isrc & IRQ_ALI) {
 507                 /* arbitration lost interrupt */
 508                 netdev_dbg(dev, "arbitration lost interrupt\n");
 509                 alc = priv->read_reg(priv, SJA1000_ALC);
 510                 priv->can.can_stats.arbitration_lost++;
 511                 if (skb) {
 512                         cf->can_id |= CAN_ERR_LOSTARB;
 513                         cf->data[0] = alc & 0x1f;
 514                 }
 515         }
 516
 517         if (state != priv->can.state) {
 518                 tx_state = txerr >= rxerr ? state : 0;
 519                 rx_state = txerr <= rxerr ? state : 0;
 520
 521                 can_change_state(dev, cf, tx_state, rx_state);
 522
 523                 if(state == CAN_STATE_BUS_OFF)
 524                         can_bus_off(dev);
 525         }
 526
 527         if (!skb)
 528                 return -ENOMEM;
 529
 530         netif_rx(skb);
 531
 532         return ret;
 533 }
 534
 535 irqreturn_t sja1000_interrupt(int irq, void *dev_id)
 536 {
 537         struct net_device *dev = (struct net_device *)dev_id;
 538         struct sja1000_priv *priv = netdev_priv(dev);
 539         struct net_device_stats *stats = &dev->stats;
 540         uint8_t isrc, status;
 541         irqreturn_t ret = 0;
 542         int n = 0, err;
 543
 544         if (priv->pre_irq)
 545                 priv->pre_irq(priv);
 546
 547         /* Shared interrupts and IRQ off? */
 548         if (priv->read_reg(priv, SJA1000_IER) == IRQ_OFF)
 549                 goto out;
 550
 551         while ((isrc = priv->read_reg(priv, SJA1000_IR)) &&
 552                (n < SJA1000_MAX_IRQ)) {
 553
 554                 status = priv->read_reg(priv, SJA1000_SR);
 555                 /* check for absent controller due to hw unplug */
 556                 if (status == 0xFF && sja1000_is_absent(priv))
 557                         goto out;
 558
 559                 if (isrc & IRQ_WUI)
 560                         netdev_warn(dev, "wakeup interrupt\n");
 561
 562                 if (isrc & IRQ_TI) {
 563                         /* transmission buffer released */
 564                         if (priv->can.ctrlmode & CAN_CTRLMODE_ONE_SHOT &&
 565                             !(status & SR_TCS)) {
 566                                 stats->tx_errors++;
 567                                 can_free_echo_skb(dev, 0, NULL);
 568                         } else {
 569                                 /* transmission complete */
 570                                 stats->tx_bytes += can_get_echo_skb(dev, 0, NULL);
 571                                 stats->tx_packets++;
 572                         }
 573                         netif_wake_queue(dev);
 574                 }
 575                 if (isrc & IRQ_RI) {
 576                         /* receive interrupt */
 577                         while (status & SR_RBS) {
 578                                 sja1000_rx(dev);
 579                                 status = priv->read_reg(priv, SJA1000_SR);
 580                                 /* check for absent controller */
 581                                 if (status == 0xFF && sja1000_is_absent(priv))
 582                                         goto out;
 583                         }
 584                 }
 585                 if (isrc & (IRQ_DOI | IRQ_EI | IRQ_BEI | IRQ_EPI | IRQ_ALI)) {
 586                         /* error interrupt */
 587                         err = sja1000_err(dev, isrc, status);
 588                         if (err == IRQ_WAKE_THREAD)
 589                                 ret = err;
 590                         if (err)
 591                                 break;
 592                 }
 593                 n++;
 594         }
 595 out:
 596         if (!ret)
 597                 ret = (n) ? IRQ_HANDLED : IRQ_NONE;
 598
 599         if (priv->post_irq)
 600                 priv->post_irq(priv);
 601
 602         if (n >= SJA1000_MAX_IRQ)
 603                 netdev_dbg(dev, "%d messages handled in ISR", n);
 604
 605         return ret;
 606 }
 607 EXPORT_SYMBOL_GPL(sja1000_interrupt);
 608
 609 static int sja1000_open(struct net_device *dev)
 610 {
 611         struct sja1000_priv *priv = netdev_priv(dev);
 612         int err;
 613
 614         /* set chip into reset mode */
 615         set_reset_mode(dev);
 616
 617         /* common open */
 618         err = open_candev(dev);
 619         if (err)
 620                 return err;
 621
 622         /* register interrupt handler, if not done by the device driver */
 623         if (!(priv->flags & SJA1000_CUSTOM_IRQ_HANDLER)) {
 624                 err = request_threaded_irq(dev->irq, sja1000_interrupt,
 625                                            sja1000_reset_interrupt,
 626                                            priv->irq_flags, dev->name, (void *)dev);
 627                 if (err) {
 628                         close_candev(dev);
 629                         return -EAGAIN;
 630                 }
 631         }
 632
 633         /* init and start chi */
 634         sja1000_start(dev);
 635
 636         netif_start_queue(dev);
 637
 638         return 0;
 639 }
 640
 641 static int sja1000_close(struct net_device *dev)
 642 {
 643         struct sja1000_priv *priv = netdev_priv(dev);
 644
 645         netif_stop_queue(dev);
 646         set_reset_mode(dev);
 647
 648         if (!(priv->flags & SJA1000_CUSTOM_IRQ_HANDLER))
 649                 free_irq(dev->irq, (void *)dev);
 650
 651         close_candev(dev);
 652
 653         return 0;
 654 }
 655
 656 struct net_device *alloc_sja1000dev(int sizeof_priv)
 657 {
 658         struct net_device *dev;
 659         struct sja1000_priv *priv;
 660
 661         dev = alloc_candev(sizeof(struct sja1000_priv) + sizeof_priv,
 662                 SJA1000_ECHO_SKB_MAX);
 663         if (!dev)
 664                 return NULL;
 665
 666         priv = netdev_priv(dev);
 667
 668         priv->dev = dev;
 669         priv->can.bittiming_const = &sja1000_bittiming_const;
 670         priv->can.do_set_bittiming = sja1000_set_bittiming;
 671         priv->can.do_set_mode = sja1000_set_mode;
 672         priv->can.do_get_berr_counter = sja1000_get_berr_counter;
 673         priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK |
 674                                        CAN_CTRLMODE_LISTENONLY |
 675                                        CAN_CTRLMODE_3_SAMPLES |
 676                                        CAN_CTRLMODE_ONE_SHOT |
 677                                        CAN_CTRLMODE_BERR_REPORTING |
 678                                        CAN_CTRLMODE_PRESUME_ACK |
 679                                        CAN_CTRLMODE_CC_LEN8_DLC;
 680
 681         spin_lock_init(&priv->cmdreg_lock);
 682
 683         if (sizeof_priv)
 684                 priv->priv = (void *)priv + sizeof(struct sja1000_priv);
 685
 686         return dev;
 687 }
 688 EXPORT_SYMBOL_GPL(alloc_sja1000dev);
 689
 690 void free_sja1000dev(struct net_device *dev)
 691 {
 692         free_candev(dev);
 693 }
 694 EXPORT_SYMBOL_GPL(free_sja1000dev);
 695
 696 static const struct net_device_ops sja1000_netdev_ops = {
 697         .ndo_open       = sja1000_open,
 698         .ndo_stop       = sja1000_close,
 699         .ndo_start_xmit = sja1000_start_xmit,
 700         .ndo_change_mtu = can_change_mtu,
 701 };
 702
 703 static const struct ethtool_ops sja1000_ethtool_ops = {
 704         .get_ts_info = ethtool_op_get_ts_info,
 705 };
 706
 707 int register_sja1000dev(struct net_device *dev)
 708 {
 709         if (!sja1000_probe_chip(dev))
 710                 return -ENODEV;
 711
 712         dev->flags |= IFF_ECHO; /* we support local echo */
 713         dev->netdev_ops = &sja1000_netdev_ops;
 714         dev->ethtool_ops = &sja1000_ethtool_ops;
 715
 716         set_reset_mode(dev);
 717         chipset_init(dev);
 718
 719         return register_candev(dev);
 720 }
 721 EXPORT_SYMBOL_GPL(register_sja1000dev);
 722
 723 void unregister_sja1000dev(struct net_device *dev)
 724 {
 725         set_reset_mode(dev);
 726         unregister_candev(dev);
 727 }
 728 EXPORT_SYMBOL_GPL(unregister_sja1000dev);
 729
 730 static __init int sja1000_init(void)
 731 {
 732         printk(KERN_INFO "%s CAN netdevice driver\n", DRV_NAME);
 733
 734         return 0;
 735 }
 736
 737 module_init(sja1000_init);
 738
 739 static __exit void sja1000_exit(void)
 740 {
 741         printk(KERN_INFO "%s: driver removed\n", DRV_NAME);
 742 }
 743
 744 module_exit(sja1000_exit);