2 * sja1000.c - Philips SJA1000 network device driver
4 * Copyright (c) 2003 Matthias Brukner, Trajet Gmbh, Rebenring 33,
5 * 38106 Braunschweig, GERMANY
7 * Copyright (c) 2002-2007 Volkswagen Group Electronic Research
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
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.
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.
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.
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
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/netdevice.h>
56 #include <linux/if_arp.h>
57 #include <linux/if_ether.h>
58 #include <linux/skbuff.h>
59 #include <linux/delay.h>
61 #include <linux/can/dev.h>
62 #include <linux/can/error.h>
66 #define DRV_NAME "sja1000"
68 MODULE_AUTHOR("Oliver Hartkopp <oliver.hartkopp@volkswagen.de>");
69 MODULE_LICENSE("Dual BSD/GPL");
70 MODULE_DESCRIPTION(DRV_NAME "CAN netdevice driver");
72 static struct can_bittiming_const sja1000_bittiming_const = {
84 static void sja1000_write_cmdreg(struct sja1000_priv *priv, u8 val)
89 * The command register needs some locking and time to settle
90 * the write_reg() operation - especially on SMP systems.
92 spin_lock_irqsave(&priv->cmdreg_lock, flags);
93 priv->write_reg(priv, REG_CMR, val);
94 priv->read_reg(priv, REG_SR);
95 spin_unlock_irqrestore(&priv->cmdreg_lock, flags);
98 static int sja1000_probe_chip(struct net_device *dev)
100 struct sja1000_priv *priv = netdev_priv(dev);
102 if (priv->reg_base && (priv->read_reg(priv, 0) == 0xFF)) {
103 printk(KERN_INFO "%s: probing @0x%lX failed\n",
104 DRV_NAME, dev->base_addr);
110 static void set_reset_mode(struct net_device *dev)
112 struct sja1000_priv *priv = netdev_priv(dev);
113 unsigned char status = priv->read_reg(priv, REG_MOD);
116 /* disable interrupts */
117 priv->write_reg(priv, REG_IER, IRQ_OFF);
119 for (i = 0; i < 100; i++) {
120 /* check reset bit */
121 if (status & MOD_RM) {
122 priv->can.state = CAN_STATE_STOPPED;
126 priv->write_reg(priv, REG_MOD, MOD_RM); /* reset chip */
128 status = priv->read_reg(priv, REG_MOD);
131 dev_err(dev->dev.parent, "setting SJA1000 into reset mode failed!\n");
134 static void set_normal_mode(struct net_device *dev)
136 struct sja1000_priv *priv = netdev_priv(dev);
137 unsigned char status = priv->read_reg(priv, REG_MOD);
140 for (i = 0; i < 100; i++) {
141 /* check reset bit */
142 if ((status & MOD_RM) == 0) {
143 priv->can.state = CAN_STATE_ERROR_ACTIVE;
144 /* enable interrupts */
145 if (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING)
146 priv->write_reg(priv, REG_IER, IRQ_ALL);
148 priv->write_reg(priv, REG_IER,
153 /* set chip to normal mode */
154 priv->write_reg(priv, REG_MOD, 0x00);
156 status = priv->read_reg(priv, REG_MOD);
159 dev_err(dev->dev.parent, "setting SJA1000 into normal mode failed!\n");
162 static void sja1000_start(struct net_device *dev)
164 struct sja1000_priv *priv = netdev_priv(dev);
166 /* leave reset mode */
167 if (priv->can.state != CAN_STATE_STOPPED)
170 /* Clear error counters and error code capture */
171 priv->write_reg(priv, REG_TXERR, 0x0);
172 priv->write_reg(priv, REG_RXERR, 0x0);
173 priv->read_reg(priv, REG_ECC);
175 /* leave reset mode */
176 set_normal_mode(dev);
179 static int sja1000_set_mode(struct net_device *dev, enum can_mode mode)
181 struct sja1000_priv *priv = netdev_priv(dev);
183 if (!priv->open_time)
189 if (netif_queue_stopped(dev))
190 netif_wake_queue(dev);
200 static int sja1000_set_bittiming(struct net_device *dev)
202 struct sja1000_priv *priv = netdev_priv(dev);
203 struct can_bittiming *bt = &priv->can.bittiming;
206 btr0 = ((bt->brp - 1) & 0x3f) | (((bt->sjw - 1) & 0x3) << 6);
207 btr1 = ((bt->prop_seg + bt->phase_seg1 - 1) & 0xf) |
208 (((bt->phase_seg2 - 1) & 0x7) << 4);
209 if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
212 dev_info(dev->dev.parent,
213 "setting BTR0=0x%02x BTR1=0x%02x\n", btr0, btr1);
215 priv->write_reg(priv, REG_BTR0, btr0);
216 priv->write_reg(priv, REG_BTR1, btr1);
221 static int sja1000_get_berr_counter(const struct net_device *dev,
222 struct can_berr_counter *bec)
224 struct sja1000_priv *priv = netdev_priv(dev);
226 bec->txerr = priv->read_reg(priv, REG_TXERR);
227 bec->rxerr = priv->read_reg(priv, REG_RXERR);
233 * initialize SJA1000 chip:
237 * - enable interrupts
238 * - start operating mode
240 static void chipset_init(struct net_device *dev)
242 struct sja1000_priv *priv = netdev_priv(dev);
244 /* set clock divider and output control register */
245 priv->write_reg(priv, REG_CDR, priv->cdr | CDR_PELICAN);
247 /* set acceptance filter (accept all) */
248 priv->write_reg(priv, REG_ACCC0, 0x00);
249 priv->write_reg(priv, REG_ACCC1, 0x00);
250 priv->write_reg(priv, REG_ACCC2, 0x00);
251 priv->write_reg(priv, REG_ACCC3, 0x00);
253 priv->write_reg(priv, REG_ACCM0, 0xFF);
254 priv->write_reg(priv, REG_ACCM1, 0xFF);
255 priv->write_reg(priv, REG_ACCM2, 0xFF);
256 priv->write_reg(priv, REG_ACCM3, 0xFF);
258 priv->write_reg(priv, REG_OCR, priv->ocr | OCR_MODE_NORMAL);
262 * transmit a CAN message
263 * message layout in the sk_buff should be like this:
264 * xx xx xx xx ff ll 00 11 22 33 44 55 66 77
265 * [ can-id ] [flags] [len] [can data (up to 8 bytes]
267 static netdev_tx_t sja1000_start_xmit(struct sk_buff *skb,
268 struct net_device *dev)
270 struct sja1000_priv *priv = netdev_priv(dev);
271 struct can_frame *cf = (struct can_frame *)skb->data;
278 if (can_dropped_invalid_skb(dev, skb))
281 netif_stop_queue(dev);
283 fi = dlc = cf->can_dlc;
286 if (id & CAN_RTR_FLAG)
289 if (id & CAN_EFF_FLAG) {
292 priv->write_reg(priv, REG_FI, fi);
293 priv->write_reg(priv, REG_ID1, (id & 0x1fe00000) >> (5 + 16));
294 priv->write_reg(priv, REG_ID2, (id & 0x001fe000) >> (5 + 8));
295 priv->write_reg(priv, REG_ID3, (id & 0x00001fe0) >> 5);
296 priv->write_reg(priv, REG_ID4, (id & 0x0000001f) << 3);
299 priv->write_reg(priv, REG_FI, fi);
300 priv->write_reg(priv, REG_ID1, (id & 0x000007f8) >> 3);
301 priv->write_reg(priv, REG_ID2, (id & 0x00000007) << 5);
304 for (i = 0; i < dlc; i++)
305 priv->write_reg(priv, dreg++, cf->data[i]);
307 can_put_echo_skb(skb, dev, 0);
309 sja1000_write_cmdreg(priv, CMD_TR);
314 static void sja1000_rx(struct net_device *dev)
316 struct sja1000_priv *priv = netdev_priv(dev);
317 struct net_device_stats *stats = &dev->stats;
318 struct can_frame *cf;
325 /* create zero'ed CAN frame buffer */
326 skb = alloc_can_skb(dev, &cf);
330 fi = priv->read_reg(priv, REG_FI);
333 /* extended frame format (EFF) */
335 id = (priv->read_reg(priv, REG_ID1) << (5 + 16))
336 | (priv->read_reg(priv, REG_ID2) << (5 + 8))
337 | (priv->read_reg(priv, REG_ID3) << 5)
338 | (priv->read_reg(priv, REG_ID4) >> 3);
341 /* standard frame format (SFF) */
343 id = (priv->read_reg(priv, REG_ID1) << 3)
344 | (priv->read_reg(priv, REG_ID2) >> 5);
347 cf->can_dlc = get_can_dlc(fi & 0x0F);
351 for (i = 0; i < cf->can_dlc; i++)
352 cf->data[i] = priv->read_reg(priv, dreg++);
357 /* release receive buffer */
358 sja1000_write_cmdreg(priv, CMD_RRB);
363 stats->rx_bytes += cf->can_dlc;
366 static int sja1000_err(struct net_device *dev, uint8_t isrc, uint8_t status)
368 struct sja1000_priv *priv = netdev_priv(dev);
369 struct net_device_stats *stats = &dev->stats;
370 struct can_frame *cf;
372 enum can_state state = priv->can.state;
375 skb = alloc_can_err_skb(dev, &cf);
379 if (isrc & IRQ_DOI) {
380 /* data overrun interrupt */
381 dev_dbg(dev->dev.parent, "data overrun interrupt\n");
382 cf->can_id |= CAN_ERR_CRTL;
383 cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
384 stats->rx_over_errors++;
386 sja1000_write_cmdreg(priv, CMD_CDO); /* clear bit */
390 /* error warning interrupt */
391 dev_dbg(dev->dev.parent, "error warning interrupt\n");
393 if (status & SR_BS) {
394 state = CAN_STATE_BUS_OFF;
395 cf->can_id |= CAN_ERR_BUSOFF;
397 } else if (status & SR_ES) {
398 state = CAN_STATE_ERROR_WARNING;
400 state = CAN_STATE_ERROR_ACTIVE;
402 if (isrc & IRQ_BEI) {
403 /* bus error interrupt */
404 priv->can.can_stats.bus_error++;
407 ecc = priv->read_reg(priv, REG_ECC);
409 cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
411 switch (ecc & ECC_MASK) {
413 cf->data[2] |= CAN_ERR_PROT_BIT;
416 cf->data[2] |= CAN_ERR_PROT_FORM;
419 cf->data[2] |= CAN_ERR_PROT_STUFF;
422 cf->data[2] |= CAN_ERR_PROT_UNSPEC;
423 cf->data[3] = ecc & ECC_SEG;
426 /* Error occurred during transmission? */
427 if ((ecc & ECC_DIR) == 0)
428 cf->data[2] |= CAN_ERR_PROT_TX;
430 if (isrc & IRQ_EPI) {
431 /* error passive interrupt */
432 dev_dbg(dev->dev.parent, "error passive interrupt\n");
434 state = CAN_STATE_ERROR_PASSIVE;
436 state = CAN_STATE_ERROR_ACTIVE;
438 if (isrc & IRQ_ALI) {
439 /* arbitration lost interrupt */
440 dev_dbg(dev->dev.parent, "arbitration lost interrupt\n");
441 alc = priv->read_reg(priv, REG_ALC);
442 priv->can.can_stats.arbitration_lost++;
444 cf->can_id |= CAN_ERR_LOSTARB;
445 cf->data[0] = alc & 0x1f;
448 if (state != priv->can.state && (state == CAN_STATE_ERROR_WARNING ||
449 state == CAN_STATE_ERROR_PASSIVE)) {
450 uint8_t rxerr = priv->read_reg(priv, REG_RXERR);
451 uint8_t txerr = priv->read_reg(priv, REG_TXERR);
452 cf->can_id |= CAN_ERR_CRTL;
453 if (state == CAN_STATE_ERROR_WARNING) {
454 priv->can.can_stats.error_warning++;
455 cf->data[1] = (txerr > rxerr) ?
456 CAN_ERR_CRTL_TX_WARNING :
457 CAN_ERR_CRTL_RX_WARNING;
459 priv->can.can_stats.error_passive++;
460 cf->data[1] = (txerr > rxerr) ?
461 CAN_ERR_CRTL_TX_PASSIVE :
462 CAN_ERR_CRTL_RX_PASSIVE;
468 priv->can.state = state;
473 stats->rx_bytes += cf->can_dlc;
478 irqreturn_t sja1000_interrupt(int irq, void *dev_id)
480 struct net_device *dev = (struct net_device *)dev_id;
481 struct sja1000_priv *priv = netdev_priv(dev);
482 struct net_device_stats *stats = &dev->stats;
483 uint8_t isrc, status;
486 /* Shared interrupts and IRQ off? */
487 if (priv->read_reg(priv, REG_IER) == IRQ_OFF)
493 while ((isrc = priv->read_reg(priv, REG_IR)) && (n < SJA1000_MAX_IRQ)) {
495 status = priv->read_reg(priv, REG_SR);
498 dev_warn(dev->dev.parent, "wakeup interrupt\n");
501 /* transmission complete interrupt */
502 stats->tx_bytes += priv->read_reg(priv, REG_FI) & 0xf;
504 can_get_echo_skb(dev, 0);
505 netif_wake_queue(dev);
508 /* receive interrupt */
509 while (status & SR_RBS) {
511 status = priv->read_reg(priv, REG_SR);
514 if (isrc & (IRQ_DOI | IRQ_EI | IRQ_BEI | IRQ_EPI | IRQ_ALI)) {
515 /* error interrupt */
516 if (sja1000_err(dev, isrc, status))
522 priv->post_irq(priv);
524 if (n >= SJA1000_MAX_IRQ)
525 dev_dbg(dev->dev.parent, "%d messages handled in ISR", n);
527 return (n) ? IRQ_HANDLED : IRQ_NONE;
529 EXPORT_SYMBOL_GPL(sja1000_interrupt);
531 static int sja1000_open(struct net_device *dev)
533 struct sja1000_priv *priv = netdev_priv(dev);
536 /* set chip into reset mode */
540 err = open_candev(dev);
544 /* register interrupt handler, if not done by the device driver */
545 if (!(priv->flags & SJA1000_CUSTOM_IRQ_HANDLER)) {
546 err = request_irq(dev->irq, sja1000_interrupt, priv->irq_flags,
547 dev->name, (void *)dev);
554 /* init and start chi */
556 priv->open_time = jiffies;
558 netif_start_queue(dev);
563 static int sja1000_close(struct net_device *dev)
565 struct sja1000_priv *priv = netdev_priv(dev);
567 netif_stop_queue(dev);
570 if (!(priv->flags & SJA1000_CUSTOM_IRQ_HANDLER))
571 free_irq(dev->irq, (void *)dev);
580 struct net_device *alloc_sja1000dev(int sizeof_priv)
582 struct net_device *dev;
583 struct sja1000_priv *priv;
585 dev = alloc_candev(sizeof(struct sja1000_priv) + sizeof_priv,
586 SJA1000_ECHO_SKB_MAX);
590 priv = netdev_priv(dev);
593 priv->can.bittiming_const = &sja1000_bittiming_const;
594 priv->can.do_set_bittiming = sja1000_set_bittiming;
595 priv->can.do_set_mode = sja1000_set_mode;
596 priv->can.do_get_berr_counter = sja1000_get_berr_counter;
597 priv->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES |
598 CAN_CTRLMODE_BERR_REPORTING;
600 spin_lock_init(&priv->cmdreg_lock);
603 priv->priv = (void *)priv + sizeof(struct sja1000_priv);
607 EXPORT_SYMBOL_GPL(alloc_sja1000dev);
609 void free_sja1000dev(struct net_device *dev)
613 EXPORT_SYMBOL_GPL(free_sja1000dev);
615 static const struct net_device_ops sja1000_netdev_ops = {
616 .ndo_open = sja1000_open,
617 .ndo_stop = sja1000_close,
618 .ndo_start_xmit = sja1000_start_xmit,
621 int register_sja1000dev(struct net_device *dev)
623 if (!sja1000_probe_chip(dev))
626 dev->flags |= IFF_ECHO; /* we support local echo */
627 dev->netdev_ops = &sja1000_netdev_ops;
632 return register_candev(dev);
634 EXPORT_SYMBOL_GPL(register_sja1000dev);
636 void unregister_sja1000dev(struct net_device *dev)
639 unregister_candev(dev);
641 EXPORT_SYMBOL_GPL(unregister_sja1000dev);
643 static __init int sja1000_init(void)
645 printk(KERN_INFO "%s CAN netdevice driver\n", DRV_NAME);
650 module_init(sja1000_init);
652 static __exit void sja1000_exit(void)
654 printk(KERN_INFO "%s: driver removed\n", DRV_NAME);
657 module_exit(sja1000_exit);