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
);