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 netif_stop_queue(dev);
254 fi = dlc = cf->can_dlc;
257 if (id & CAN_RTR_FLAG)
260 if (id & CAN_EFF_FLAG) {
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);
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);
275 for (i = 0; i < dlc; i++)
276 priv->write_reg(priv, dreg++, cf->data[i]);
278 dev->trans_start = jiffies;
280 can_put_echo_skb(skb, dev, 0);
282 priv->write_reg(priv, REG_CMR, CMD_TR);
287 static void sja1000_rx(struct net_device *dev)
289 struct sja1000_priv *priv = netdev_priv(dev);
290 struct net_device_stats *stats = &dev->stats;
291 struct can_frame *cf;
298 /* create zero'ed CAN frame buffer */
299 skb = alloc_can_skb(dev, &cf);
303 fi = priv->read_reg(priv, REG_FI);
306 /* extended frame format (EFF) */
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);
314 /* standard frame format (SFF) */
316 id = (priv->read_reg(priv, REG_ID1) << 3)
317 | (priv->read_reg(priv, REG_ID2) >> 5);
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++);
330 /* release receive buffer */
331 priv->write_reg(priv, REG_CMR, CMD_RRB);
336 stats->rx_bytes += cf->can_dlc;
339 static int sja1000_err(struct net_device *dev, uint8_t isrc, uint8_t status)
341 struct sja1000_priv *priv = netdev_priv(dev);
342 struct net_device_stats *stats = &dev->stats;
343 struct can_frame *cf;
345 enum can_state state = priv->can.state;
348 skb = alloc_can_err_skb(dev, &cf);
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++;
359 priv->write_reg(priv, REG_CMR, CMD_CDO); /* clear bit */
363 /* error warning interrupt */
364 dev_dbg(dev->dev.parent, "error warning interrupt\n");
366 if (status & SR_BS) {
367 state = CAN_STATE_BUS_OFF;
368 cf->can_id |= CAN_ERR_BUSOFF;
370 } else if (status & SR_ES) {
371 state = CAN_STATE_ERROR_WARNING;
373 state = CAN_STATE_ERROR_ACTIVE;
375 if (isrc & IRQ_BEI) {
376 /* bus error interrupt */
377 priv->can.can_stats.bus_error++;
380 ecc = priv->read_reg(priv, REG_ECC);
382 cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
384 switch (ecc & ECC_MASK) {
386 cf->data[2] |= CAN_ERR_PROT_BIT;
389 cf->data[2] |= CAN_ERR_PROT_FORM;
392 cf->data[2] |= CAN_ERR_PROT_STUFF;
395 cf->data[2] |= CAN_ERR_PROT_UNSPEC;
396 cf->data[3] = ecc & ECC_SEG;
399 /* Error occured during transmission? */
400 if ((ecc & ECC_DIR) == 0)
401 cf->data[2] |= CAN_ERR_PROT_TX;
403 if (isrc & IRQ_EPI) {
404 /* error passive interrupt */
405 dev_dbg(dev->dev.parent, "error passive interrupt\n");
407 state = CAN_STATE_ERROR_PASSIVE;
409 state = CAN_STATE_ERROR_ACTIVE;
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++;
417 cf->can_id |= CAN_ERR_LOSTARB;
418 cf->data[0] = alc & 0x1f;
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;
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;
439 priv->can.state = state;
444 stats->rx_bytes += cf->can_dlc;
449 irqreturn_t sja1000_interrupt(int irq, void *dev_id)
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;
457 /* Shared interrupts and IRQ off? */
458 if (priv->read_reg(priv, REG_IER) == IRQ_OFF)
464 while ((isrc = priv->read_reg(priv, REG_IR)) && (n < SJA1000_MAX_IRQ)) {
466 status = priv->read_reg(priv, REG_SR);
469 dev_warn(dev->dev.parent, "wakeup interrupt\n");
472 /* transmission complete interrupt */
473 stats->tx_bytes += priv->read_reg(priv, REG_FI) & 0xf;
475 can_get_echo_skb(dev, 0);
476 netif_wake_queue(dev);
479 /* receive interrupt */
480 while (status & SR_RBS) {
482 status = priv->read_reg(priv, REG_SR);
485 if (isrc & (IRQ_DOI | IRQ_EI | IRQ_BEI | IRQ_EPI | IRQ_ALI)) {
486 /* error interrupt */
487 if (sja1000_err(dev, isrc, status))
493 priv->post_irq(priv);
495 if (n >= SJA1000_MAX_IRQ)
496 dev_dbg(dev->dev.parent, "%d messages handled in ISR", n);
498 return (n) ? IRQ_HANDLED : IRQ_NONE;
500 EXPORT_SYMBOL_GPL(sja1000_interrupt);
502 static int sja1000_open(struct net_device *dev)
504 struct sja1000_priv *priv = netdev_priv(dev);
507 /* set chip into reset mode */
511 err = open_candev(dev);
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);
525 /* init and start chi */
527 priv->open_time = jiffies;
529 netif_start_queue(dev);
534 static int sja1000_close(struct net_device *dev)
536 struct sja1000_priv *priv = netdev_priv(dev);
538 netif_stop_queue(dev);
541 if (!(priv->flags & SJA1000_CUSTOM_IRQ_HANDLER))
542 free_irq(dev->irq, (void *)dev);
551 struct net_device *alloc_sja1000dev(int sizeof_priv)
553 struct net_device *dev;
554 struct sja1000_priv *priv;
556 dev = alloc_candev(sizeof(struct sja1000_priv) + sizeof_priv,
557 SJA1000_ECHO_SKB_MAX);
561 priv = netdev_priv(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;
569 priv->priv = (void *)priv + sizeof(struct sja1000_priv);
573 EXPORT_SYMBOL_GPL(alloc_sja1000dev);
575 void free_sja1000dev(struct net_device *dev)
579 EXPORT_SYMBOL_GPL(free_sja1000dev);
581 static 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,
587 int register_sja1000dev(struct net_device *dev)
589 if (!sja1000_probe_chip(dev))
592 dev->flags |= IFF_ECHO; /* we support local echo */
593 dev->netdev_ops = &sja1000_netdev_ops;
598 return register_candev(dev);
600 EXPORT_SYMBOL_GPL(register_sja1000dev);
602 void unregister_sja1000dev(struct net_device *dev)
605 unregister_candev(dev);
607 EXPORT_SYMBOL_GPL(unregister_sja1000dev);
609 static __init int sja1000_init(void)
611 printk(KERN_INFO "%s CAN netdevice driver\n", DRV_NAME);
616 module_init(sja1000_init);
618 static __exit void sja1000_exit(void)
620 printk(KERN_INFO "%s: driver removed\n", DRV_NAME);
623 module_exit(sja1000_exit);