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
43 * Send feedback to <socketcan-users@lists.berlios.de>
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>
63 #include <linux/can.h>
64 #include <linux/can/dev.h>
65 #include <linux/can/error.h>
69 #define DRV_NAME "sja1000"
71 MODULE_AUTHOR("Oliver Hartkopp <oliver.hartkopp@volkswagen.de>");
72 MODULE_LICENSE("Dual BSD/GPL");
73 MODULE_DESCRIPTION(DRV_NAME "CAN netdevice driver");
75 static struct can_bittiming_const sja1000_bittiming_const = {
87 static int sja1000_probe_chip(struct net_device *dev)
89 struct sja1000_priv *priv = netdev_priv(dev);
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);
99 static void set_reset_mode(struct net_device *dev)
101 struct sja1000_priv *priv = netdev_priv(dev);
102 unsigned char status = priv->read_reg(priv, REG_MOD);
105 /* disable interrupts */
106 priv->write_reg(priv, REG_IER, IRQ_OFF);
108 for (i = 0; i < 100; i++) {
109 /* check reset bit */
110 if (status & MOD_RM) {
111 priv->can.state = CAN_STATE_STOPPED;
115 priv->write_reg(priv, REG_MOD, MOD_RM); /* reset chip */
117 status = priv->read_reg(priv, REG_MOD);
120 dev_err(dev->dev.parent, "setting SJA1000 into reset mode failed!\n");
123 static void set_normal_mode(struct net_device *dev)
125 struct sja1000_priv *priv = netdev_priv(dev);
126 unsigned char status = priv->read_reg(priv, REG_MOD);
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);
138 /* set chip to normal mode */
139 priv->write_reg(priv, REG_MOD, 0x00);
141 status = priv->read_reg(priv, REG_MOD);
144 dev_err(dev->dev.parent, "setting SJA1000 into normal mode failed!\n");
147 static void sja1000_start(struct net_device *dev)
149 struct sja1000_priv *priv = netdev_priv(dev);
151 /* leave reset mode */
152 if (priv->can.state != CAN_STATE_STOPPED)
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);
160 /* leave reset mode */
161 set_normal_mode(dev);
164 static int sja1000_set_mode(struct net_device *dev, enum can_mode mode)
166 struct sja1000_priv *priv = netdev_priv(dev);
168 if (!priv->open_time)
174 if (netif_queue_stopped(dev))
175 netif_wake_queue(dev);
185 static int sja1000_set_bittiming(struct net_device *dev)
187 struct sja1000_priv *priv = netdev_priv(dev);
188 struct can_bittiming *bt = &priv->can.bittiming;
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)
197 dev_info(dev->dev.parent,
198 "setting BTR0=0x%02x BTR1=0x%02x\n", btr0, btr1);
200 priv->write_reg(priv, REG_BTR0, btr0);
201 priv->write_reg(priv, REG_BTR1, btr1);
207 * initialize SJA1000 chip:
211 * - enable interrupts
212 * - start operating mode
214 static void chipset_init(struct net_device *dev)
216 struct sja1000_priv *priv = netdev_priv(dev);
218 /* set clock divider and output control register */
219 priv->write_reg(priv, REG_CDR, priv->cdr | CDR_PELICAN);
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);
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);
232 priv->write_reg(priv, REG_OCR, priv->ocr | OCR_MODE_NORMAL);
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]
241 static netdev_tx_t sja1000_start_xmit(struct sk_buff *skb,
242 struct net_device *dev)
244 struct sja1000_priv *priv = netdev_priv(dev);
245 struct can_frame *cf = (struct can_frame *)skb->data;
252 if (can_dropped_invalid_skb(dev, skb))
255 netif_stop_queue(dev);
257 fi = dlc = cf->can_dlc;
260 if (id & CAN_RTR_FLAG)
263 if (id & CAN_EFF_FLAG) {
266 priv->write_reg(priv, REG_FI, fi);
267 priv->write_reg(priv, REG_ID1, (id & 0x1fe00000) >> (5 + 16));
268 priv->write_reg(priv, REG_ID2, (id & 0x001fe000) >> (5 + 8));
269 priv->write_reg(priv, REG_ID3, (id & 0x00001fe0) >> 5);
270 priv->write_reg(priv, REG_ID4, (id & 0x0000001f) << 3);
273 priv->write_reg(priv, REG_FI, fi);
274 priv->write_reg(priv, REG_ID1, (id & 0x000007f8) >> 3);
275 priv->write_reg(priv, REG_ID2, (id & 0x00000007) << 5);
278 for (i = 0; i < dlc; i++)
279 priv->write_reg(priv, dreg++, cf->data[i]);
281 dev->trans_start = jiffies;
283 can_put_echo_skb(skb, dev, 0);
285 priv->write_reg(priv, REG_CMR, CMD_TR);
290 static void sja1000_rx(struct net_device *dev)
292 struct sja1000_priv *priv = netdev_priv(dev);
293 struct net_device_stats *stats = &dev->stats;
294 struct can_frame *cf;
301 /* create zero'ed CAN frame buffer */
302 skb = alloc_can_skb(dev, &cf);
306 fi = priv->read_reg(priv, REG_FI);
309 /* extended frame format (EFF) */
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);
317 /* standard frame format (SFF) */
319 id = (priv->read_reg(priv, REG_ID1) << 3)
320 | (priv->read_reg(priv, REG_ID2) >> 5);
326 cf->can_dlc = get_can_dlc(fi & 0x0F);
327 for (i = 0; i < cf->can_dlc; i++)
328 cf->data[i] = priv->read_reg(priv, dreg++);
333 /* release receive buffer */
334 priv->write_reg(priv, REG_CMR, CMD_RRB);
339 stats->rx_bytes += cf->can_dlc;
342 static int sja1000_err(struct net_device *dev, uint8_t isrc, uint8_t status)
344 struct sja1000_priv *priv = netdev_priv(dev);
345 struct net_device_stats *stats = &dev->stats;
346 struct can_frame *cf;
348 enum can_state state = priv->can.state;
351 skb = alloc_can_err_skb(dev, &cf);
355 if (isrc & IRQ_DOI) {
356 /* data overrun interrupt */
357 dev_dbg(dev->dev.parent, "data overrun interrupt\n");
358 cf->can_id |= CAN_ERR_CRTL;
359 cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
360 stats->rx_over_errors++;
362 priv->write_reg(priv, REG_CMR, CMD_CDO); /* clear bit */
366 /* error warning interrupt */
367 dev_dbg(dev->dev.parent, "error warning interrupt\n");
369 if (status & SR_BS) {
370 state = CAN_STATE_BUS_OFF;
371 cf->can_id |= CAN_ERR_BUSOFF;
373 } else if (status & SR_ES) {
374 state = CAN_STATE_ERROR_WARNING;
376 state = CAN_STATE_ERROR_ACTIVE;
378 if (isrc & IRQ_BEI) {
379 /* bus error interrupt */
380 priv->can.can_stats.bus_error++;
383 ecc = priv->read_reg(priv, REG_ECC);
385 cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
387 switch (ecc & ECC_MASK) {
389 cf->data[2] |= CAN_ERR_PROT_BIT;
392 cf->data[2] |= CAN_ERR_PROT_FORM;
395 cf->data[2] |= CAN_ERR_PROT_STUFF;
398 cf->data[2] |= CAN_ERR_PROT_UNSPEC;
399 cf->data[3] = ecc & ECC_SEG;
402 /* Error occured during transmission? */
403 if ((ecc & ECC_DIR) == 0)
404 cf->data[2] |= CAN_ERR_PROT_TX;
406 if (isrc & IRQ_EPI) {
407 /* error passive interrupt */
408 dev_dbg(dev->dev.parent, "error passive interrupt\n");
410 state = CAN_STATE_ERROR_PASSIVE;
412 state = CAN_STATE_ERROR_ACTIVE;
414 if (isrc & IRQ_ALI) {
415 /* arbitration lost interrupt */
416 dev_dbg(dev->dev.parent, "arbitration lost interrupt\n");
417 alc = priv->read_reg(priv, REG_ALC);
418 priv->can.can_stats.arbitration_lost++;
420 cf->can_id |= CAN_ERR_LOSTARB;
421 cf->data[0] = alc & 0x1f;
424 if (state != priv->can.state && (state == CAN_STATE_ERROR_WARNING ||
425 state == CAN_STATE_ERROR_PASSIVE)) {
426 uint8_t rxerr = priv->read_reg(priv, REG_RXERR);
427 uint8_t txerr = priv->read_reg(priv, REG_TXERR);
428 cf->can_id |= CAN_ERR_CRTL;
429 if (state == CAN_STATE_ERROR_WARNING) {
430 priv->can.can_stats.error_warning++;
431 cf->data[1] = (txerr > rxerr) ?
432 CAN_ERR_CRTL_TX_WARNING :
433 CAN_ERR_CRTL_RX_WARNING;
435 priv->can.can_stats.error_passive++;
436 cf->data[1] = (txerr > rxerr) ?
437 CAN_ERR_CRTL_TX_PASSIVE :
438 CAN_ERR_CRTL_RX_PASSIVE;
442 priv->can.state = state;
447 stats->rx_bytes += cf->can_dlc;
452 irqreturn_t sja1000_interrupt(int irq, void *dev_id)
454 struct net_device *dev = (struct net_device *)dev_id;
455 struct sja1000_priv *priv = netdev_priv(dev);
456 struct net_device_stats *stats = &dev->stats;
457 uint8_t isrc, status;
460 /* Shared interrupts and IRQ off? */
461 if (priv->read_reg(priv, REG_IER) == IRQ_OFF)
467 while ((isrc = priv->read_reg(priv, REG_IR)) && (n < SJA1000_MAX_IRQ)) {
469 status = priv->read_reg(priv, REG_SR);
472 dev_warn(dev->dev.parent, "wakeup interrupt\n");
475 /* transmission complete interrupt */
476 stats->tx_bytes += priv->read_reg(priv, REG_FI) & 0xf;
478 can_get_echo_skb(dev, 0);
479 netif_wake_queue(dev);
482 /* receive interrupt */
483 while (status & SR_RBS) {
485 status = priv->read_reg(priv, REG_SR);
488 if (isrc & (IRQ_DOI | IRQ_EI | IRQ_BEI | IRQ_EPI | IRQ_ALI)) {
489 /* error interrupt */
490 if (sja1000_err(dev, isrc, status))
496 priv->post_irq(priv);
498 if (n >= SJA1000_MAX_IRQ)
499 dev_dbg(dev->dev.parent, "%d messages handled in ISR", n);
501 return (n) ? IRQ_HANDLED : IRQ_NONE;
503 EXPORT_SYMBOL_GPL(sja1000_interrupt);
505 static int sja1000_open(struct net_device *dev)
507 struct sja1000_priv *priv = netdev_priv(dev);
510 /* set chip into reset mode */
514 err = open_candev(dev);
518 /* register interrupt handler, if not done by the device driver */
519 if (!(priv->flags & SJA1000_CUSTOM_IRQ_HANDLER)) {
520 err = request_irq(dev->irq, sja1000_interrupt, priv->irq_flags,
521 dev->name, (void *)dev);
528 /* init and start chi */
530 priv->open_time = jiffies;
532 netif_start_queue(dev);
537 static int sja1000_close(struct net_device *dev)
539 struct sja1000_priv *priv = netdev_priv(dev);
541 netif_stop_queue(dev);
544 if (!(priv->flags & SJA1000_CUSTOM_IRQ_HANDLER))
545 free_irq(dev->irq, (void *)dev);
554 struct net_device *alloc_sja1000dev(int sizeof_priv)
556 struct net_device *dev;
557 struct sja1000_priv *priv;
559 dev = alloc_candev(sizeof(struct sja1000_priv) + sizeof_priv,
560 SJA1000_ECHO_SKB_MAX);
564 priv = netdev_priv(dev);
567 priv->can.bittiming_const = &sja1000_bittiming_const;
568 priv->can.do_set_bittiming = sja1000_set_bittiming;
569 priv->can.do_set_mode = sja1000_set_mode;
570 priv->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES;
573 priv->priv = (void *)priv + sizeof(struct sja1000_priv);
577 EXPORT_SYMBOL_GPL(alloc_sja1000dev);
579 void free_sja1000dev(struct net_device *dev)
583 EXPORT_SYMBOL_GPL(free_sja1000dev);
585 static const struct net_device_ops sja1000_netdev_ops = {
586 .ndo_open = sja1000_open,
587 .ndo_stop = sja1000_close,
588 .ndo_start_xmit = sja1000_start_xmit,
591 int register_sja1000dev(struct net_device *dev)
593 if (!sja1000_probe_chip(dev))
596 dev->flags |= IFF_ECHO; /* we support local echo */
597 dev->netdev_ops = &sja1000_netdev_ops;
602 return register_candev(dev);
604 EXPORT_SYMBOL_GPL(register_sja1000dev);
606 void unregister_sja1000dev(struct net_device *dev)
609 unregister_candev(dev);
611 EXPORT_SYMBOL_GPL(unregister_sja1000dev);
613 static __init int sja1000_init(void)
615 printk(KERN_INFO "%s CAN netdevice driver\n", DRV_NAME);
620 module_init(sja1000_init);
622 static __exit void sja1000_exit(void)
624 printk(KERN_INFO "%s: driver removed\n", DRV_NAME);
627 module_exit(sja1000_exit);