1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
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>
60
61#include <linux/can/dev.h>
62#include <linux/can/error.h>
63#include <linux/can/led.h>
64
65#include "sja1000.h"
66
67#define DRV_NAME "sja1000"
68
69MODULE_AUTHOR("Oliver Hartkopp <oliver.hartkopp@volkswagen.de>");
70MODULE_LICENSE("Dual BSD/GPL");
71MODULE_DESCRIPTION(DRV_NAME "CAN netdevice driver");
72
73static const struct can_bittiming_const sja1000_bittiming_const = {
74 .name = DRV_NAME,
75 .tseg1_min = 1,
76 .tseg1_max = 16,
77 .tseg2_min = 1,
78 .tseg2_max = 8,
79 .sjw_max = 4,
80 .brp_min = 1,
81 .brp_max = 64,
82 .brp_inc = 1,
83};
84
85static void sja1000_write_cmdreg(struct sja1000_priv *priv, u8 val)
86{
87 unsigned long flags;
88
89
90
91
92
93 spin_lock_irqsave(&priv->cmdreg_lock, flags);
94 priv->write_reg(priv, SJA1000_CMR, val);
95 priv->read_reg(priv, SJA1000_SR);
96 spin_unlock_irqrestore(&priv->cmdreg_lock, flags);
97}
98
99static int sja1000_is_absent(struct sja1000_priv *priv)
100{
101 return (priv->read_reg(priv, SJA1000_MOD) == 0xFF);
102}
103
104static int sja1000_probe_chip(struct net_device *dev)
105{
106 struct sja1000_priv *priv = netdev_priv(dev);
107
108 if (priv->reg_base && sja1000_is_absent(priv)) {
109 netdev_err(dev, "probing failed\n");
110 return 0;
111 }
112 return -1;
113}
114
115static void set_reset_mode(struct net_device *dev)
116{
117 struct sja1000_priv *priv = netdev_priv(dev);
118 unsigned char status = priv->read_reg(priv, SJA1000_MOD);
119 int i;
120
121
122 priv->write_reg(priv, SJA1000_IER, IRQ_OFF);
123
124 for (i = 0; i < 100; i++) {
125
126 if (status & MOD_RM) {
127 priv->can.state = CAN_STATE_STOPPED;
128 return;
129 }
130
131
132 priv->write_reg(priv, SJA1000_MOD, MOD_RM);
133 udelay(10);
134 status = priv->read_reg(priv, SJA1000_MOD);
135 }
136
137 netdev_err(dev, "setting SJA1000 into reset mode failed!\n");
138}
139
140static void set_normal_mode(struct net_device *dev)
141{
142 struct sja1000_priv *priv = netdev_priv(dev);
143 unsigned char status = priv->read_reg(priv, SJA1000_MOD);
144 u8 mod_reg_val = 0x00;
145 int i;
146
147 for (i = 0; i < 100; i++) {
148
149 if ((status & MOD_RM) == 0) {
150 priv->can.state = CAN_STATE_ERROR_ACTIVE;
151
152 if (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING)
153 priv->write_reg(priv, SJA1000_IER, IRQ_ALL);
154 else
155 priv->write_reg(priv, SJA1000_IER,
156 IRQ_ALL & ~IRQ_BEI);
157 return;
158 }
159
160
161 if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
162 mod_reg_val |= MOD_LOM;
163 if (priv->can.ctrlmode & CAN_CTRLMODE_PRESUME_ACK)
164 mod_reg_val |= MOD_STM;
165 priv->write_reg(priv, SJA1000_MOD, mod_reg_val);
166
167 udelay(10);
168
169 status = priv->read_reg(priv, SJA1000_MOD);
170 }
171
172 netdev_err(dev, "setting SJA1000 into normal mode failed!\n");
173}
174
175
176
177
178
179
180
181
182
183static void chipset_init(struct net_device *dev)
184{
185 struct sja1000_priv *priv = netdev_priv(dev);
186
187
188 priv->write_reg(priv, SJA1000_CDR, priv->cdr | CDR_PELICAN);
189
190
191 priv->write_reg(priv, SJA1000_ACCC0, 0x00);
192 priv->write_reg(priv, SJA1000_ACCC1, 0x00);
193 priv->write_reg(priv, SJA1000_ACCC2, 0x00);
194 priv->write_reg(priv, SJA1000_ACCC3, 0x00);
195
196 priv->write_reg(priv, SJA1000_ACCM0, 0xFF);
197 priv->write_reg(priv, SJA1000_ACCM1, 0xFF);
198 priv->write_reg(priv, SJA1000_ACCM2, 0xFF);
199 priv->write_reg(priv, SJA1000_ACCM3, 0xFF);
200
201 priv->write_reg(priv, SJA1000_OCR, priv->ocr | OCR_MODE_NORMAL);
202}
203
204static void sja1000_start(struct net_device *dev)
205{
206 struct sja1000_priv *priv = netdev_priv(dev);
207
208
209 if (priv->can.state != CAN_STATE_STOPPED)
210 set_reset_mode(dev);
211
212
213 if (!(priv->read_reg(priv, SJA1000_CDR) & CDR_PELICAN))
214 chipset_init(dev);
215
216
217 priv->write_reg(priv, SJA1000_TXERR, 0x0);
218 priv->write_reg(priv, SJA1000_RXERR, 0x0);
219 priv->read_reg(priv, SJA1000_ECC);
220
221
222 set_normal_mode(dev);
223}
224
225static int sja1000_set_mode(struct net_device *dev, enum can_mode mode)
226{
227 switch (mode) {
228 case CAN_MODE_START:
229 sja1000_start(dev);
230 if (netif_queue_stopped(dev))
231 netif_wake_queue(dev);
232 break;
233
234 default:
235 return -EOPNOTSUPP;
236 }
237
238 return 0;
239}
240
241static int sja1000_set_bittiming(struct net_device *dev)
242{
243 struct sja1000_priv *priv = netdev_priv(dev);
244 struct can_bittiming *bt = &priv->can.bittiming;
245 u8 btr0, btr1;
246
247 btr0 = ((bt->brp - 1) & 0x3f) | (((bt->sjw - 1) & 0x3) << 6);
248 btr1 = ((bt->prop_seg + bt->phase_seg1 - 1) & 0xf) |
249 (((bt->phase_seg2 - 1) & 0x7) << 4);
250 if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
251 btr1 |= 0x80;
252
253 netdev_info(dev, "setting BTR0=0x%02x BTR1=0x%02x\n", btr0, btr1);
254
255 priv->write_reg(priv, SJA1000_BTR0, btr0);
256 priv->write_reg(priv, SJA1000_BTR1, btr1);
257
258 return 0;
259}
260
261static int sja1000_get_berr_counter(const struct net_device *dev,
262 struct can_berr_counter *bec)
263{
264 struct sja1000_priv *priv = netdev_priv(dev);
265
266 bec->txerr = priv->read_reg(priv, SJA1000_TXERR);
267 bec->rxerr = priv->read_reg(priv, SJA1000_RXERR);
268
269 return 0;
270}
271
272
273
274
275
276
277
278static netdev_tx_t sja1000_start_xmit(struct sk_buff *skb,
279 struct net_device *dev)
280{
281 struct sja1000_priv *priv = netdev_priv(dev);
282 struct can_frame *cf = (struct can_frame *)skb->data;
283 uint8_t fi;
284 uint8_t dlc;
285 canid_t id;
286 uint8_t dreg;
287 u8 cmd_reg_val = 0x00;
288 int i;
289
290 if (can_dropped_invalid_skb(dev, skb))
291 return NETDEV_TX_OK;
292
293 netif_stop_queue(dev);
294
295 fi = dlc = cf->can_dlc;
296 id = cf->can_id;
297
298 if (id & CAN_RTR_FLAG)
299 fi |= SJA1000_FI_RTR;
300
301 if (id & CAN_EFF_FLAG) {
302 fi |= SJA1000_FI_FF;
303 dreg = SJA1000_EFF_BUF;
304 priv->write_reg(priv, SJA1000_FI, fi);
305 priv->write_reg(priv, SJA1000_ID1, (id & 0x1fe00000) >> 21);
306 priv->write_reg(priv, SJA1000_ID2, (id & 0x001fe000) >> 13);
307 priv->write_reg(priv, SJA1000_ID3, (id & 0x00001fe0) >> 5);
308 priv->write_reg(priv, SJA1000_ID4, (id & 0x0000001f) << 3);
309 } else {
310 dreg = SJA1000_SFF_BUF;
311 priv->write_reg(priv, SJA1000_FI, fi);
312 priv->write_reg(priv, SJA1000_ID1, (id & 0x000007f8) >> 3);
313 priv->write_reg(priv, SJA1000_ID2, (id & 0x00000007) << 5);
314 }
315
316 for (i = 0; i < dlc; i++)
317 priv->write_reg(priv, dreg++, cf->data[i]);
318
319 can_put_echo_skb(skb, dev, 0);
320
321 if (priv->can.ctrlmode & CAN_CTRLMODE_ONE_SHOT)
322 cmd_reg_val |= CMD_AT;
323
324 if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
325 cmd_reg_val |= CMD_SRR;
326 else
327 cmd_reg_val |= CMD_TR;
328
329 sja1000_write_cmdreg(priv, cmd_reg_val);
330
331 return NETDEV_TX_OK;
332}
333
334static void sja1000_rx(struct net_device *dev)
335{
336 struct sja1000_priv *priv = netdev_priv(dev);
337 struct net_device_stats *stats = &dev->stats;
338 struct can_frame *cf;
339 struct sk_buff *skb;
340 uint8_t fi;
341 uint8_t dreg;
342 canid_t id;
343 int i;
344
345
346 skb = alloc_can_skb(dev, &cf);
347 if (skb == NULL)
348 return;
349
350 fi = priv->read_reg(priv, SJA1000_FI);
351
352 if (fi & SJA1000_FI_FF) {
353
354 dreg = SJA1000_EFF_BUF;
355 id = (priv->read_reg(priv, SJA1000_ID1) << 21)
356 | (priv->read_reg(priv, SJA1000_ID2) << 13)
357 | (priv->read_reg(priv, SJA1000_ID3) << 5)
358 | (priv->read_reg(priv, SJA1000_ID4) >> 3);
359 id |= CAN_EFF_FLAG;
360 } else {
361
362 dreg = SJA1000_SFF_BUF;
363 id = (priv->read_reg(priv, SJA1000_ID1) << 3)
364 | (priv->read_reg(priv, SJA1000_ID2) >> 5);
365 }
366
367 cf->can_dlc = get_can_dlc(fi & 0x0F);
368 if (fi & SJA1000_FI_RTR) {
369 id |= CAN_RTR_FLAG;
370 } else {
371 for (i = 0; i < cf->can_dlc; i++)
372 cf->data[i] = priv->read_reg(priv, dreg++);
373 }
374
375 cf->can_id = id;
376
377
378 sja1000_write_cmdreg(priv, CMD_RRB);
379
380 netif_rx(skb);
381
382 stats->rx_packets++;
383 stats->rx_bytes += cf->can_dlc;
384
385 can_led_event(dev, CAN_LED_EVENT_RX);
386}
387
388static int sja1000_err(struct net_device *dev, uint8_t isrc, uint8_t status)
389{
390 struct sja1000_priv *priv = netdev_priv(dev);
391 struct net_device_stats *stats = &dev->stats;
392 struct can_frame *cf;
393 struct sk_buff *skb;
394 enum can_state state = priv->can.state;
395 uint8_t ecc, alc;
396
397 skb = alloc_can_err_skb(dev, &cf);
398 if (skb == NULL)
399 return -ENOMEM;
400
401 if (isrc & IRQ_DOI) {
402
403 netdev_dbg(dev, "data overrun interrupt\n");
404 cf->can_id |= CAN_ERR_CRTL;
405 cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
406 stats->rx_over_errors++;
407 stats->rx_errors++;
408 sja1000_write_cmdreg(priv, CMD_CDO);
409 }
410
411 if (isrc & IRQ_EI) {
412
413 netdev_dbg(dev, "error warning interrupt\n");
414
415 if (status & SR_BS) {
416 state = CAN_STATE_BUS_OFF;
417 cf->can_id |= CAN_ERR_BUSOFF;
418 can_bus_off(dev);
419 } else if (status & SR_ES) {
420 state = CAN_STATE_ERROR_WARNING;
421 } else
422 state = CAN_STATE_ERROR_ACTIVE;
423 }
424 if (isrc & IRQ_BEI) {
425
426 priv->can.can_stats.bus_error++;
427 stats->rx_errors++;
428
429 ecc = priv->read_reg(priv, SJA1000_ECC);
430
431 cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
432
433 switch (ecc & ECC_MASK) {
434 case ECC_BIT:
435 cf->data[2] |= CAN_ERR_PROT_BIT;
436 break;
437 case ECC_FORM:
438 cf->data[2] |= CAN_ERR_PROT_FORM;
439 break;
440 case ECC_STUFF:
441 cf->data[2] |= CAN_ERR_PROT_STUFF;
442 break;
443 default:
444 cf->data[2] |= CAN_ERR_PROT_UNSPEC;
445 cf->data[3] = ecc & ECC_SEG;
446 break;
447 }
448
449 if ((ecc & ECC_DIR) == 0)
450 cf->data[2] |= CAN_ERR_PROT_TX;
451 }
452 if (isrc & IRQ_EPI) {
453
454 netdev_dbg(dev, "error passive interrupt\n");
455 if (status & SR_ES)
456 state = CAN_STATE_ERROR_PASSIVE;
457 else
458 state = CAN_STATE_ERROR_ACTIVE;
459 }
460 if (isrc & IRQ_ALI) {
461
462 netdev_dbg(dev, "arbitration lost interrupt\n");
463 alc = priv->read_reg(priv, SJA1000_ALC);
464 priv->can.can_stats.arbitration_lost++;
465 stats->tx_errors++;
466 cf->can_id |= CAN_ERR_LOSTARB;
467 cf->data[0] = alc & 0x1f;
468 }
469
470 if (state != priv->can.state && (state == CAN_STATE_ERROR_WARNING ||
471 state == CAN_STATE_ERROR_PASSIVE)) {
472 uint8_t rxerr = priv->read_reg(priv, SJA1000_RXERR);
473 uint8_t txerr = priv->read_reg(priv, SJA1000_TXERR);
474 cf->can_id |= CAN_ERR_CRTL;
475 if (state == CAN_STATE_ERROR_WARNING) {
476 priv->can.can_stats.error_warning++;
477 cf->data[1] = (txerr > rxerr) ?
478 CAN_ERR_CRTL_TX_WARNING :
479 CAN_ERR_CRTL_RX_WARNING;
480 } else {
481 priv->can.can_stats.error_passive++;
482 cf->data[1] = (txerr > rxerr) ?
483 CAN_ERR_CRTL_TX_PASSIVE :
484 CAN_ERR_CRTL_RX_PASSIVE;
485 }
486 cf->data[6] = txerr;
487 cf->data[7] = rxerr;
488 }
489
490 priv->can.state = state;
491
492 netif_rx(skb);
493
494 stats->rx_packets++;
495 stats->rx_bytes += cf->can_dlc;
496
497 return 0;
498}
499
500irqreturn_t sja1000_interrupt(int irq, void *dev_id)
501{
502 struct net_device *dev = (struct net_device *)dev_id;
503 struct sja1000_priv *priv = netdev_priv(dev);
504 struct net_device_stats *stats = &dev->stats;
505 uint8_t isrc, status;
506 int n = 0;
507
508 if (priv->pre_irq)
509 priv->pre_irq(priv);
510
511
512 if (priv->read_reg(priv, SJA1000_IER) == IRQ_OFF)
513 goto out;
514
515 while ((isrc = priv->read_reg(priv, SJA1000_IR)) &&
516 (n < SJA1000_MAX_IRQ)) {
517
518 status = priv->read_reg(priv, SJA1000_SR);
519
520 if (status == 0xFF && sja1000_is_absent(priv))
521 goto out;
522
523 if (isrc & IRQ_WUI)
524 netdev_warn(dev, "wakeup interrupt\n");
525
526 if (isrc & IRQ_TI) {
527
528 if (priv->can.ctrlmode & CAN_CTRLMODE_ONE_SHOT &&
529 !(status & SR_TCS)) {
530 stats->tx_errors++;
531 can_free_echo_skb(dev, 0);
532 } else {
533
534 stats->tx_bytes +=
535 priv->read_reg(priv, SJA1000_FI) & 0xf;
536 stats->tx_packets++;
537 can_get_echo_skb(dev, 0);
538 }
539 netif_wake_queue(dev);
540 can_led_event(dev, CAN_LED_EVENT_TX);
541 }
542 if (isrc & IRQ_RI) {
543
544 while (status & SR_RBS) {
545 sja1000_rx(dev);
546 status = priv->read_reg(priv, SJA1000_SR);
547
548 if (status == 0xFF && sja1000_is_absent(priv))
549 goto out;
550 }
551 }
552 if (isrc & (IRQ_DOI | IRQ_EI | IRQ_BEI | IRQ_EPI | IRQ_ALI)) {
553
554 if (sja1000_err(dev, isrc, status))
555 break;
556 }
557 n++;
558 }
559out:
560 if (priv->post_irq)
561 priv->post_irq(priv);
562
563 if (n >= SJA1000_MAX_IRQ)
564 netdev_dbg(dev, "%d messages handled in ISR", n);
565
566 return (n) ? IRQ_HANDLED : IRQ_NONE;
567}
568EXPORT_SYMBOL_GPL(sja1000_interrupt);
569
570static int sja1000_open(struct net_device *dev)
571{
572 struct sja1000_priv *priv = netdev_priv(dev);
573 int err;
574
575
576 set_reset_mode(dev);
577
578
579 err = open_candev(dev);
580 if (err)
581 return err;
582
583
584 if (!(priv->flags & SJA1000_CUSTOM_IRQ_HANDLER)) {
585 err = request_irq(dev->irq, sja1000_interrupt, priv->irq_flags,
586 dev->name, (void *)dev);
587 if (err) {
588 close_candev(dev);
589 return -EAGAIN;
590 }
591 }
592
593
594 sja1000_start(dev);
595
596 can_led_event(dev, CAN_LED_EVENT_OPEN);
597
598 netif_start_queue(dev);
599
600 return 0;
601}
602
603static int sja1000_close(struct net_device *dev)
604{
605 struct sja1000_priv *priv = netdev_priv(dev);
606
607 netif_stop_queue(dev);
608 set_reset_mode(dev);
609
610 if (!(priv->flags & SJA1000_CUSTOM_IRQ_HANDLER))
611 free_irq(dev->irq, (void *)dev);
612
613 close_candev(dev);
614
615 can_led_event(dev, CAN_LED_EVENT_STOP);
616
617 return 0;
618}
619
620struct net_device *alloc_sja1000dev(int sizeof_priv)
621{
622 struct net_device *dev;
623 struct sja1000_priv *priv;
624
625 dev = alloc_candev(sizeof(struct sja1000_priv) + sizeof_priv,
626 SJA1000_ECHO_SKB_MAX);
627 if (!dev)
628 return NULL;
629
630 priv = netdev_priv(dev);
631
632 priv->dev = dev;
633 priv->can.bittiming_const = &sja1000_bittiming_const;
634 priv->can.do_set_bittiming = sja1000_set_bittiming;
635 priv->can.do_set_mode = sja1000_set_mode;
636 priv->can.do_get_berr_counter = sja1000_get_berr_counter;
637 priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK |
638 CAN_CTRLMODE_LISTENONLY |
639 CAN_CTRLMODE_3_SAMPLES |
640 CAN_CTRLMODE_ONE_SHOT |
641 CAN_CTRLMODE_BERR_REPORTING |
642 CAN_CTRLMODE_PRESUME_ACK;
643
644 spin_lock_init(&priv->cmdreg_lock);
645
646 if (sizeof_priv)
647 priv->priv = (void *)priv + sizeof(struct sja1000_priv);
648
649 return dev;
650}
651EXPORT_SYMBOL_GPL(alloc_sja1000dev);
652
653void free_sja1000dev(struct net_device *dev)
654{
655 free_candev(dev);
656}
657EXPORT_SYMBOL_GPL(free_sja1000dev);
658
659static const struct net_device_ops sja1000_netdev_ops = {
660 .ndo_open = sja1000_open,
661 .ndo_stop = sja1000_close,
662 .ndo_start_xmit = sja1000_start_xmit,
663 .ndo_change_mtu = can_change_mtu,
664};
665
666int register_sja1000dev(struct net_device *dev)
667{
668 int ret;
669
670 if (!sja1000_probe_chip(dev))
671 return -ENODEV;
672
673 dev->flags |= IFF_ECHO;
674 dev->netdev_ops = &sja1000_netdev_ops;
675
676 set_reset_mode(dev);
677 chipset_init(dev);
678
679 ret = register_candev(dev);
680
681 if (!ret)
682 devm_can_led_init(dev);
683
684 return ret;
685}
686EXPORT_SYMBOL_GPL(register_sja1000dev);
687
688void unregister_sja1000dev(struct net_device *dev)
689{
690 set_reset_mode(dev);
691 unregister_candev(dev);
692}
693EXPORT_SYMBOL_GPL(unregister_sja1000dev);
694
695static __init int sja1000_init(void)
696{
697 printk(KERN_INFO "%s CAN netdevice driver\n", DRV_NAME);
698
699 return 0;
700}
701
702module_init(sja1000_init);
703
704static __exit void sja1000_exit(void)
705{
706 printk(KERN_INFO "%s: driver removed\n", DRV_NAME);
707}
708
709module_exit(sja1000_exit);
710