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_is_absent(struct sja1000_priv
*priv
)
100 return (priv
->read_reg(priv
, REG_MOD
) == 0xFF);
103 static int sja1000_probe_chip(struct net_device
*dev
)
105 struct sja1000_priv
*priv
= netdev_priv(dev
);
107 if (priv
->reg_base
&& sja1000_is_absent(priv
)) {
108 printk(KERN_INFO
"%s: probing @0x%lX failed\n",
109 DRV_NAME
, dev
->base_addr
);
115 static void set_reset_mode(struct net_device
*dev
)
117 struct sja1000_priv
*priv
= netdev_priv(dev
);
118 unsigned char status
= priv
->read_reg(priv
, REG_MOD
);
121 /* disable interrupts */
122 priv
->write_reg(priv
, REG_IER
, IRQ_OFF
);
124 for (i
= 0; i
< 100; i
++) {
125 /* check reset bit */
126 if (status
& MOD_RM
) {
127 priv
->can
.state
= CAN_STATE_STOPPED
;
131 priv
->write_reg(priv
, REG_MOD
, MOD_RM
); /* reset chip */
133 status
= priv
->read_reg(priv
, REG_MOD
);
136 dev_err(dev
->dev
.parent
, "setting SJA1000 into reset mode failed!\n");
139 static void set_normal_mode(struct net_device
*dev
)
141 struct sja1000_priv
*priv
= netdev_priv(dev
);
142 unsigned char status
= priv
->read_reg(priv
, REG_MOD
);
145 for (i
= 0; i
< 100; i
++) {
146 /* check reset bit */
147 if ((status
& MOD_RM
) == 0) {
148 priv
->can
.state
= CAN_STATE_ERROR_ACTIVE
;
149 /* enable interrupts */
150 if (priv
->can
.ctrlmode
& CAN_CTRLMODE_BERR_REPORTING
)
151 priv
->write_reg(priv
, REG_IER
, IRQ_ALL
);
153 priv
->write_reg(priv
, REG_IER
,
158 /* set chip to normal mode */
159 priv
->write_reg(priv
, REG_MOD
, 0x00);
161 status
= priv
->read_reg(priv
, REG_MOD
);
164 dev_err(dev
->dev
.parent
, "setting SJA1000 into normal mode failed!\n");
167 static void sja1000_start(struct net_device
*dev
)
169 struct sja1000_priv
*priv
= netdev_priv(dev
);
171 /* leave reset mode */
172 if (priv
->can
.state
!= CAN_STATE_STOPPED
)
175 /* Clear error counters and error code capture */
176 priv
->write_reg(priv
, REG_TXERR
, 0x0);
177 priv
->write_reg(priv
, REG_RXERR
, 0x0);
178 priv
->read_reg(priv
, REG_ECC
);
180 /* leave reset mode */
181 set_normal_mode(dev
);
184 static int sja1000_set_mode(struct net_device
*dev
, enum can_mode mode
)
186 struct sja1000_priv
*priv
= netdev_priv(dev
);
188 if (!priv
->open_time
)
194 if (netif_queue_stopped(dev
))
195 netif_wake_queue(dev
);
205 static int sja1000_set_bittiming(struct net_device
*dev
)
207 struct sja1000_priv
*priv
= netdev_priv(dev
);
208 struct can_bittiming
*bt
= &priv
->can
.bittiming
;
211 btr0
= ((bt
->brp
- 1) & 0x3f) | (((bt
->sjw
- 1) & 0x3) << 6);
212 btr1
= ((bt
->prop_seg
+ bt
->phase_seg1
- 1) & 0xf) |
213 (((bt
->phase_seg2
- 1) & 0x7) << 4);
214 if (priv
->can
.ctrlmode
& CAN_CTRLMODE_3_SAMPLES
)
217 dev_info(dev
->dev
.parent
,
218 "setting BTR0=0x%02x BTR1=0x%02x\n", btr0
, btr1
);
220 priv
->write_reg(priv
, REG_BTR0
, btr0
);
221 priv
->write_reg(priv
, REG_BTR1
, btr1
);
226 static int sja1000_get_berr_counter(const struct net_device
*dev
,
227 struct can_berr_counter
*bec
)
229 struct sja1000_priv
*priv
= netdev_priv(dev
);
231 bec
->txerr
= priv
->read_reg(priv
, REG_TXERR
);
232 bec
->rxerr
= priv
->read_reg(priv
, REG_RXERR
);
238 * initialize SJA1000 chip:
242 * - enable interrupts
243 * - start operating mode
245 static void chipset_init(struct net_device
*dev
)
247 struct sja1000_priv
*priv
= netdev_priv(dev
);
249 /* set clock divider and output control register */
250 priv
->write_reg(priv
, REG_CDR
, priv
->cdr
| CDR_PELICAN
);
252 /* set acceptance filter (accept all) */
253 priv
->write_reg(priv
, REG_ACCC0
, 0x00);
254 priv
->write_reg(priv
, REG_ACCC1
, 0x00);
255 priv
->write_reg(priv
, REG_ACCC2
, 0x00);
256 priv
->write_reg(priv
, REG_ACCC3
, 0x00);
258 priv
->write_reg(priv
, REG_ACCM0
, 0xFF);
259 priv
->write_reg(priv
, REG_ACCM1
, 0xFF);
260 priv
->write_reg(priv
, REG_ACCM2
, 0xFF);
261 priv
->write_reg(priv
, REG_ACCM3
, 0xFF);
263 priv
->write_reg(priv
, REG_OCR
, priv
->ocr
| OCR_MODE_NORMAL
);
267 * transmit a CAN message
268 * message layout in the sk_buff should be like this:
269 * xx xx xx xx ff ll 00 11 22 33 44 55 66 77
270 * [ can-id ] [flags] [len] [can data (up to 8 bytes]
272 static netdev_tx_t
sja1000_start_xmit(struct sk_buff
*skb
,
273 struct net_device
*dev
)
275 struct sja1000_priv
*priv
= netdev_priv(dev
);
276 struct can_frame
*cf
= (struct can_frame
*)skb
->data
;
283 if (can_dropped_invalid_skb(dev
, skb
))
286 netif_stop_queue(dev
);
288 fi
= dlc
= cf
->can_dlc
;
291 if (id
& CAN_RTR_FLAG
)
294 if (id
& CAN_EFF_FLAG
) {
297 priv
->write_reg(priv
, REG_FI
, fi
);
298 priv
->write_reg(priv
, REG_ID1
, (id
& 0x1fe00000) >> (5 + 16));
299 priv
->write_reg(priv
, REG_ID2
, (id
& 0x001fe000) >> (5 + 8));
300 priv
->write_reg(priv
, REG_ID3
, (id
& 0x00001fe0) >> 5);
301 priv
->write_reg(priv
, REG_ID4
, (id
& 0x0000001f) << 3);
304 priv
->write_reg(priv
, REG_FI
, fi
);
305 priv
->write_reg(priv
, REG_ID1
, (id
& 0x000007f8) >> 3);
306 priv
->write_reg(priv
, REG_ID2
, (id
& 0x00000007) << 5);
309 for (i
= 0; i
< dlc
; i
++)
310 priv
->write_reg(priv
, dreg
++, cf
->data
[i
]);
312 can_put_echo_skb(skb
, dev
, 0);
314 sja1000_write_cmdreg(priv
, CMD_TR
);
319 static void sja1000_rx(struct net_device
*dev
)
321 struct sja1000_priv
*priv
= netdev_priv(dev
);
322 struct net_device_stats
*stats
= &dev
->stats
;
323 struct can_frame
*cf
;
330 /* create zero'ed CAN frame buffer */
331 skb
= alloc_can_skb(dev
, &cf
);
335 fi
= priv
->read_reg(priv
, REG_FI
);
338 /* extended frame format (EFF) */
340 id
= (priv
->read_reg(priv
, REG_ID1
) << (5 + 16))
341 | (priv
->read_reg(priv
, REG_ID2
) << (5 + 8))
342 | (priv
->read_reg(priv
, REG_ID3
) << 5)
343 | (priv
->read_reg(priv
, REG_ID4
) >> 3);
346 /* standard frame format (SFF) */
348 id
= (priv
->read_reg(priv
, REG_ID1
) << 3)
349 | (priv
->read_reg(priv
, REG_ID2
) >> 5);
352 cf
->can_dlc
= get_can_dlc(fi
& 0x0F);
356 for (i
= 0; i
< cf
->can_dlc
; i
++)
357 cf
->data
[i
] = priv
->read_reg(priv
, dreg
++);
362 /* release receive buffer */
363 sja1000_write_cmdreg(priv
, CMD_RRB
);
368 stats
->rx_bytes
+= cf
->can_dlc
;
371 static int sja1000_err(struct net_device
*dev
, uint8_t isrc
, uint8_t status
)
373 struct sja1000_priv
*priv
= netdev_priv(dev
);
374 struct net_device_stats
*stats
= &dev
->stats
;
375 struct can_frame
*cf
;
377 enum can_state state
= priv
->can
.state
;
380 skb
= alloc_can_err_skb(dev
, &cf
);
384 if (isrc
& IRQ_DOI
) {
385 /* data overrun interrupt */
386 dev_dbg(dev
->dev
.parent
, "data overrun interrupt\n");
387 cf
->can_id
|= CAN_ERR_CRTL
;
388 cf
->data
[1] = CAN_ERR_CRTL_RX_OVERFLOW
;
389 stats
->rx_over_errors
++;
391 sja1000_write_cmdreg(priv
, CMD_CDO
); /* clear bit */
395 /* error warning interrupt */
396 dev_dbg(dev
->dev
.parent
, "error warning interrupt\n");
398 if (status
& SR_BS
) {
399 state
= CAN_STATE_BUS_OFF
;
400 cf
->can_id
|= CAN_ERR_BUSOFF
;
402 } else if (status
& SR_ES
) {
403 state
= CAN_STATE_ERROR_WARNING
;
405 state
= CAN_STATE_ERROR_ACTIVE
;
407 if (isrc
& IRQ_BEI
) {
408 /* bus error interrupt */
409 priv
->can
.can_stats
.bus_error
++;
412 ecc
= priv
->read_reg(priv
, REG_ECC
);
414 cf
->can_id
|= CAN_ERR_PROT
| CAN_ERR_BUSERROR
;
416 switch (ecc
& ECC_MASK
) {
418 cf
->data
[2] |= CAN_ERR_PROT_BIT
;
421 cf
->data
[2] |= CAN_ERR_PROT_FORM
;
424 cf
->data
[2] |= CAN_ERR_PROT_STUFF
;
427 cf
->data
[2] |= CAN_ERR_PROT_UNSPEC
;
428 cf
->data
[3] = ecc
& ECC_SEG
;
431 /* Error occurred during transmission? */
432 if ((ecc
& ECC_DIR
) == 0)
433 cf
->data
[2] |= CAN_ERR_PROT_TX
;
435 if (isrc
& IRQ_EPI
) {
436 /* error passive interrupt */
437 dev_dbg(dev
->dev
.parent
, "error passive interrupt\n");
439 state
= CAN_STATE_ERROR_PASSIVE
;
441 state
= CAN_STATE_ERROR_ACTIVE
;
443 if (isrc
& IRQ_ALI
) {
444 /* arbitration lost interrupt */
445 dev_dbg(dev
->dev
.parent
, "arbitration lost interrupt\n");
446 alc
= priv
->read_reg(priv
, REG_ALC
);
447 priv
->can
.can_stats
.arbitration_lost
++;
449 cf
->can_id
|= CAN_ERR_LOSTARB
;
450 cf
->data
[0] = alc
& 0x1f;
453 if (state
!= priv
->can
.state
&& (state
== CAN_STATE_ERROR_WARNING
||
454 state
== CAN_STATE_ERROR_PASSIVE
)) {
455 uint8_t rxerr
= priv
->read_reg(priv
, REG_RXERR
);
456 uint8_t txerr
= priv
->read_reg(priv
, REG_TXERR
);
457 cf
->can_id
|= CAN_ERR_CRTL
;
458 if (state
== CAN_STATE_ERROR_WARNING
) {
459 priv
->can
.can_stats
.error_warning
++;
460 cf
->data
[1] = (txerr
> rxerr
) ?
461 CAN_ERR_CRTL_TX_WARNING
:
462 CAN_ERR_CRTL_RX_WARNING
;
464 priv
->can
.can_stats
.error_passive
++;
465 cf
->data
[1] = (txerr
> rxerr
) ?
466 CAN_ERR_CRTL_TX_PASSIVE
:
467 CAN_ERR_CRTL_RX_PASSIVE
;
473 priv
->can
.state
= state
;
478 stats
->rx_bytes
+= cf
->can_dlc
;
483 irqreturn_t
sja1000_interrupt(int irq
, void *dev_id
)
485 struct net_device
*dev
= (struct net_device
*)dev_id
;
486 struct sja1000_priv
*priv
= netdev_priv(dev
);
487 struct net_device_stats
*stats
= &dev
->stats
;
488 uint8_t isrc
, status
;
491 /* Shared interrupts and IRQ off? */
492 if (priv
->read_reg(priv
, REG_IER
) == IRQ_OFF
)
498 while ((isrc
= priv
->read_reg(priv
, REG_IR
)) && (n
< SJA1000_MAX_IRQ
)) {
500 status
= priv
->read_reg(priv
, REG_SR
);
501 /* check for absent controller due to hw unplug */
502 if (status
== 0xFF && sja1000_is_absent(priv
))
506 dev_warn(dev
->dev
.parent
, "wakeup interrupt\n");
509 /* transmission complete interrupt */
510 stats
->tx_bytes
+= priv
->read_reg(priv
, REG_FI
) & 0xf;
512 can_get_echo_skb(dev
, 0);
513 netif_wake_queue(dev
);
516 /* receive interrupt */
517 while (status
& SR_RBS
) {
519 status
= priv
->read_reg(priv
, REG_SR
);
520 /* check for absent controller */
521 if (status
== 0xFF && sja1000_is_absent(priv
))
525 if (isrc
& (IRQ_DOI
| IRQ_EI
| IRQ_BEI
| IRQ_EPI
| IRQ_ALI
)) {
526 /* error interrupt */
527 if (sja1000_err(dev
, isrc
, status
))
533 priv
->post_irq(priv
);
535 if (n
>= SJA1000_MAX_IRQ
)
536 dev_dbg(dev
->dev
.parent
, "%d messages handled in ISR", n
);
538 return (n
) ? IRQ_HANDLED
: IRQ_NONE
;
540 EXPORT_SYMBOL_GPL(sja1000_interrupt
);
542 static int sja1000_open(struct net_device
*dev
)
544 struct sja1000_priv
*priv
= netdev_priv(dev
);
547 /* set chip into reset mode */
551 err
= open_candev(dev
);
555 /* register interrupt handler, if not done by the device driver */
556 if (!(priv
->flags
& SJA1000_CUSTOM_IRQ_HANDLER
)) {
557 err
= request_irq(dev
->irq
, sja1000_interrupt
, priv
->irq_flags
,
558 dev
->name
, (void *)dev
);
565 /* init and start chi */
567 priv
->open_time
= jiffies
;
569 netif_start_queue(dev
);
574 static int sja1000_close(struct net_device
*dev
)
576 struct sja1000_priv
*priv
= netdev_priv(dev
);
578 netif_stop_queue(dev
);
581 if (!(priv
->flags
& SJA1000_CUSTOM_IRQ_HANDLER
))
582 free_irq(dev
->irq
, (void *)dev
);
591 struct net_device
*alloc_sja1000dev(int sizeof_priv
)
593 struct net_device
*dev
;
594 struct sja1000_priv
*priv
;
596 dev
= alloc_candev(sizeof(struct sja1000_priv
) + sizeof_priv
,
597 SJA1000_ECHO_SKB_MAX
);
601 priv
= netdev_priv(dev
);
604 priv
->can
.bittiming_const
= &sja1000_bittiming_const
;
605 priv
->can
.do_set_bittiming
= sja1000_set_bittiming
;
606 priv
->can
.do_set_mode
= sja1000_set_mode
;
607 priv
->can
.do_get_berr_counter
= sja1000_get_berr_counter
;
608 priv
->can
.ctrlmode_supported
= CAN_CTRLMODE_3_SAMPLES
|
609 CAN_CTRLMODE_BERR_REPORTING
;
611 spin_lock_init(&priv
->cmdreg_lock
);
614 priv
->priv
= (void *)priv
+ sizeof(struct sja1000_priv
);
618 EXPORT_SYMBOL_GPL(alloc_sja1000dev
);
620 void free_sja1000dev(struct net_device
*dev
)
624 EXPORT_SYMBOL_GPL(free_sja1000dev
);
626 static const struct net_device_ops sja1000_netdev_ops
= {
627 .ndo_open
= sja1000_open
,
628 .ndo_stop
= sja1000_close
,
629 .ndo_start_xmit
= sja1000_start_xmit
,
632 int register_sja1000dev(struct net_device
*dev
)
634 if (!sja1000_probe_chip(dev
))
637 dev
->flags
|= IFF_ECHO
; /* we support local echo */
638 dev
->netdev_ops
= &sja1000_netdev_ops
;
643 return register_candev(dev
);
645 EXPORT_SYMBOL_GPL(register_sja1000dev
);
647 void unregister_sja1000dev(struct net_device
*dev
)
650 unregister_candev(dev
);
652 EXPORT_SYMBOL_GPL(unregister_sja1000dev
);
654 static __init
int sja1000_init(void)
656 printk(KERN_INFO
"%s CAN netdevice driver\n", DRV_NAME
);
661 module_init(sja1000_init
);
663 static __exit
void sja1000_exit(void)
665 printk(KERN_INFO
"%s: driver removed\n", DRV_NAME
);
668 module_exit(sja1000_exit
);