This source file includes following definitions.
- sja1000_write_cmdreg
- sja1000_is_absent
- sja1000_probe_chip
- set_reset_mode
- set_normal_mode
- chipset_init
- sja1000_start
- sja1000_set_mode
- sja1000_set_bittiming
- sja1000_get_berr_counter
- sja1000_start_xmit
- sja1000_rx
- sja1000_err
- sja1000_interrupt
- sja1000_open
- sja1000_close
- alloc_sja1000dev
- free_sja1000dev
- register_sja1000dev
- unregister_sja1000dev
- sja1000_init
- sja1000_exit
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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
69 MODULE_AUTHOR("Oliver Hartkopp <oliver.hartkopp@volkswagen.de>");
70 MODULE_LICENSE("Dual BSD/GPL");
71 MODULE_DESCRIPTION(DRV_NAME "CAN netdevice driver");
72
73 static 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
85 static 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
99 static int sja1000_is_absent(struct sja1000_priv *priv)
100 {
101 return (priv->read_reg(priv, SJA1000_MOD) == 0xFF);
102 }
103
104 static 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
115 static 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
140 static 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
183 static 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
204 static 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 priv->read_reg(priv, SJA1000_IR);
223
224
225 set_normal_mode(dev);
226 }
227
228 static int sja1000_set_mode(struct net_device *dev, enum can_mode mode)
229 {
230 switch (mode) {
231 case CAN_MODE_START:
232 sja1000_start(dev);
233 if (netif_queue_stopped(dev))
234 netif_wake_queue(dev);
235 break;
236
237 default:
238 return -EOPNOTSUPP;
239 }
240
241 return 0;
242 }
243
244 static int sja1000_set_bittiming(struct net_device *dev)
245 {
246 struct sja1000_priv *priv = netdev_priv(dev);
247 struct can_bittiming *bt = &priv->can.bittiming;
248 u8 btr0, btr1;
249
250 btr0 = ((bt->brp - 1) & 0x3f) | (((bt->sjw - 1) & 0x3) << 6);
251 btr1 = ((bt->prop_seg + bt->phase_seg1 - 1) & 0xf) |
252 (((bt->phase_seg2 - 1) & 0x7) << 4);
253 if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
254 btr1 |= 0x80;
255
256 netdev_info(dev, "setting BTR0=0x%02x BTR1=0x%02x\n", btr0, btr1);
257
258 priv->write_reg(priv, SJA1000_BTR0, btr0);
259 priv->write_reg(priv, SJA1000_BTR1, btr1);
260
261 return 0;
262 }
263
264 static int sja1000_get_berr_counter(const struct net_device *dev,
265 struct can_berr_counter *bec)
266 {
267 struct sja1000_priv *priv = netdev_priv(dev);
268
269 bec->txerr = priv->read_reg(priv, SJA1000_TXERR);
270 bec->rxerr = priv->read_reg(priv, SJA1000_RXERR);
271
272 return 0;
273 }
274
275
276
277
278
279
280
281 static netdev_tx_t sja1000_start_xmit(struct sk_buff *skb,
282 struct net_device *dev)
283 {
284 struct sja1000_priv *priv = netdev_priv(dev);
285 struct can_frame *cf = (struct can_frame *)skb->data;
286 uint8_t fi;
287 uint8_t dlc;
288 canid_t id;
289 uint8_t dreg;
290 u8 cmd_reg_val = 0x00;
291 int i;
292
293 if (can_dropped_invalid_skb(dev, skb))
294 return NETDEV_TX_OK;
295
296 netif_stop_queue(dev);
297
298 fi = dlc = cf->can_dlc;
299 id = cf->can_id;
300
301 if (id & CAN_RTR_FLAG)
302 fi |= SJA1000_FI_RTR;
303
304 if (id & CAN_EFF_FLAG) {
305 fi |= SJA1000_FI_FF;
306 dreg = SJA1000_EFF_BUF;
307 priv->write_reg(priv, SJA1000_FI, fi);
308 priv->write_reg(priv, SJA1000_ID1, (id & 0x1fe00000) >> 21);
309 priv->write_reg(priv, SJA1000_ID2, (id & 0x001fe000) >> 13);
310 priv->write_reg(priv, SJA1000_ID3, (id & 0x00001fe0) >> 5);
311 priv->write_reg(priv, SJA1000_ID4, (id & 0x0000001f) << 3);
312 } else {
313 dreg = SJA1000_SFF_BUF;
314 priv->write_reg(priv, SJA1000_FI, fi);
315 priv->write_reg(priv, SJA1000_ID1, (id & 0x000007f8) >> 3);
316 priv->write_reg(priv, SJA1000_ID2, (id & 0x00000007) << 5);
317 }
318
319 for (i = 0; i < dlc; i++)
320 priv->write_reg(priv, dreg++, cf->data[i]);
321
322 can_put_echo_skb(skb, dev, 0);
323
324 if (priv->can.ctrlmode & CAN_CTRLMODE_ONE_SHOT)
325 cmd_reg_val |= CMD_AT;
326
327 if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
328 cmd_reg_val |= CMD_SRR;
329 else
330 cmd_reg_val |= CMD_TR;
331
332 sja1000_write_cmdreg(priv, cmd_reg_val);
333
334 return NETDEV_TX_OK;
335 }
336
337 static void sja1000_rx(struct net_device *dev)
338 {
339 struct sja1000_priv *priv = netdev_priv(dev);
340 struct net_device_stats *stats = &dev->stats;
341 struct can_frame *cf;
342 struct sk_buff *skb;
343 uint8_t fi;
344 uint8_t dreg;
345 canid_t id;
346 int i;
347
348
349 skb = alloc_can_skb(dev, &cf);
350 if (skb == NULL)
351 return;
352
353 fi = priv->read_reg(priv, SJA1000_FI);
354
355 if (fi & SJA1000_FI_FF) {
356
357 dreg = SJA1000_EFF_BUF;
358 id = (priv->read_reg(priv, SJA1000_ID1) << 21)
359 | (priv->read_reg(priv, SJA1000_ID2) << 13)
360 | (priv->read_reg(priv, SJA1000_ID3) << 5)
361 | (priv->read_reg(priv, SJA1000_ID4) >> 3);
362 id |= CAN_EFF_FLAG;
363 } else {
364
365 dreg = SJA1000_SFF_BUF;
366 id = (priv->read_reg(priv, SJA1000_ID1) << 3)
367 | (priv->read_reg(priv, SJA1000_ID2) >> 5);
368 }
369
370 cf->can_dlc = get_can_dlc(fi & 0x0F);
371 if (fi & SJA1000_FI_RTR) {
372 id |= CAN_RTR_FLAG;
373 } else {
374 for (i = 0; i < cf->can_dlc; i++)
375 cf->data[i] = priv->read_reg(priv, dreg++);
376 }
377
378 cf->can_id = id;
379
380
381 sja1000_write_cmdreg(priv, CMD_RRB);
382
383 stats->rx_packets++;
384 stats->rx_bytes += cf->can_dlc;
385 netif_rx(skb);
386
387 can_led_event(dev, CAN_LED_EVENT_RX);
388 }
389
390 static int sja1000_err(struct net_device *dev, uint8_t isrc, uint8_t status)
391 {
392 struct sja1000_priv *priv = netdev_priv(dev);
393 struct net_device_stats *stats = &dev->stats;
394 struct can_frame *cf;
395 struct sk_buff *skb;
396 enum can_state state = priv->can.state;
397 enum can_state rx_state, tx_state;
398 unsigned int rxerr, txerr;
399 uint8_t ecc, alc;
400
401 skb = alloc_can_err_skb(dev, &cf);
402 if (skb == NULL)
403 return -ENOMEM;
404
405 txerr = priv->read_reg(priv, SJA1000_TXERR);
406 rxerr = priv->read_reg(priv, SJA1000_RXERR);
407
408 cf->data[6] = txerr;
409 cf->data[7] = rxerr;
410
411 if (isrc & IRQ_DOI) {
412
413 netdev_dbg(dev, "data overrun interrupt\n");
414 cf->can_id |= CAN_ERR_CRTL;
415 cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
416 stats->rx_over_errors++;
417 stats->rx_errors++;
418 sja1000_write_cmdreg(priv, CMD_CDO);
419 }
420
421 if (isrc & IRQ_EI) {
422
423 netdev_dbg(dev, "error warning interrupt\n");
424
425 if (status & SR_BS)
426 state = CAN_STATE_BUS_OFF;
427 else if (status & SR_ES)
428 state = CAN_STATE_ERROR_WARNING;
429 else
430 state = CAN_STATE_ERROR_ACTIVE;
431 }
432 if (isrc & IRQ_BEI) {
433
434 priv->can.can_stats.bus_error++;
435 stats->rx_errors++;
436
437 ecc = priv->read_reg(priv, SJA1000_ECC);
438
439 cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
440
441
442 switch (ecc & ECC_MASK) {
443 case ECC_BIT:
444 cf->data[2] |= CAN_ERR_PROT_BIT;
445 break;
446 case ECC_FORM:
447 cf->data[2] |= CAN_ERR_PROT_FORM;
448 break;
449 case ECC_STUFF:
450 cf->data[2] |= CAN_ERR_PROT_STUFF;
451 break;
452 default:
453 break;
454 }
455
456
457 cf->data[3] = ecc & ECC_SEG;
458
459
460 if ((ecc & ECC_DIR) == 0)
461 cf->data[2] |= CAN_ERR_PROT_TX;
462 }
463 if (isrc & IRQ_EPI) {
464
465 netdev_dbg(dev, "error passive interrupt\n");
466
467 if (state == CAN_STATE_ERROR_PASSIVE)
468 state = CAN_STATE_ERROR_WARNING;
469 else
470 state = CAN_STATE_ERROR_PASSIVE;
471 }
472 if (isrc & IRQ_ALI) {
473
474 netdev_dbg(dev, "arbitration lost interrupt\n");
475 alc = priv->read_reg(priv, SJA1000_ALC);
476 priv->can.can_stats.arbitration_lost++;
477 stats->tx_errors++;
478 cf->can_id |= CAN_ERR_LOSTARB;
479 cf->data[0] = alc & 0x1f;
480 }
481
482 if (state != priv->can.state) {
483 tx_state = txerr >= rxerr ? state : 0;
484 rx_state = txerr <= rxerr ? state : 0;
485
486 can_change_state(dev, cf, tx_state, rx_state);
487
488 if(state == CAN_STATE_BUS_OFF)
489 can_bus_off(dev);
490 }
491
492 stats->rx_packets++;
493 stats->rx_bytes += cf->can_dlc;
494 netif_rx(skb);
495
496 return 0;
497 }
498
499 irqreturn_t sja1000_interrupt(int irq, void *dev_id)
500 {
501 struct net_device *dev = (struct net_device *)dev_id;
502 struct sja1000_priv *priv = netdev_priv(dev);
503 struct net_device_stats *stats = &dev->stats;
504 uint8_t isrc, status;
505 int n = 0;
506
507 if (priv->pre_irq)
508 priv->pre_irq(priv);
509
510
511 if (priv->read_reg(priv, SJA1000_IER) == IRQ_OFF)
512 goto out;
513
514 while ((isrc = priv->read_reg(priv, SJA1000_IR)) &&
515 (n < SJA1000_MAX_IRQ)) {
516
517 status = priv->read_reg(priv, SJA1000_SR);
518
519 if (status == 0xFF && sja1000_is_absent(priv))
520 goto out;
521
522 if (isrc & IRQ_WUI)
523 netdev_warn(dev, "wakeup interrupt\n");
524
525 if (isrc & IRQ_TI) {
526
527 if (priv->can.ctrlmode & CAN_CTRLMODE_ONE_SHOT &&
528 !(status & SR_TCS)) {
529 stats->tx_errors++;
530 can_free_echo_skb(dev, 0);
531 } else {
532
533 stats->tx_bytes +=
534 priv->read_reg(priv, SJA1000_FI) & 0xf;
535 stats->tx_packets++;
536 can_get_echo_skb(dev, 0);
537 }
538 netif_wake_queue(dev);
539 can_led_event(dev, CAN_LED_EVENT_TX);
540 }
541 if (isrc & IRQ_RI) {
542
543 while (status & SR_RBS) {
544 sja1000_rx(dev);
545 status = priv->read_reg(priv, SJA1000_SR);
546
547 if (status == 0xFF && sja1000_is_absent(priv))
548 goto out;
549 }
550 }
551 if (isrc & (IRQ_DOI | IRQ_EI | IRQ_BEI | IRQ_EPI | IRQ_ALI)) {
552
553 if (sja1000_err(dev, isrc, status))
554 break;
555 }
556 n++;
557 }
558 out:
559 if (priv->post_irq)
560 priv->post_irq(priv);
561
562 if (n >= SJA1000_MAX_IRQ)
563 netdev_dbg(dev, "%d messages handled in ISR", n);
564
565 return (n) ? IRQ_HANDLED : IRQ_NONE;
566 }
567 EXPORT_SYMBOL_GPL(sja1000_interrupt);
568
569 static int sja1000_open(struct net_device *dev)
570 {
571 struct sja1000_priv *priv = netdev_priv(dev);
572 int err;
573
574
575 set_reset_mode(dev);
576
577
578 err = open_candev(dev);
579 if (err)
580 return err;
581
582
583 if (!(priv->flags & SJA1000_CUSTOM_IRQ_HANDLER)) {
584 err = request_irq(dev->irq, sja1000_interrupt, priv->irq_flags,
585 dev->name, (void *)dev);
586 if (err) {
587 close_candev(dev);
588 return -EAGAIN;
589 }
590 }
591
592
593 sja1000_start(dev);
594
595 can_led_event(dev, CAN_LED_EVENT_OPEN);
596
597 netif_start_queue(dev);
598
599 return 0;
600 }
601
602 static int sja1000_close(struct net_device *dev)
603 {
604 struct sja1000_priv *priv = netdev_priv(dev);
605
606 netif_stop_queue(dev);
607 set_reset_mode(dev);
608
609 if (!(priv->flags & SJA1000_CUSTOM_IRQ_HANDLER))
610 free_irq(dev->irq, (void *)dev);
611
612 close_candev(dev);
613
614 can_led_event(dev, CAN_LED_EVENT_STOP);
615
616 return 0;
617 }
618
619 struct net_device *alloc_sja1000dev(int sizeof_priv)
620 {
621 struct net_device *dev;
622 struct sja1000_priv *priv;
623
624 dev = alloc_candev(sizeof(struct sja1000_priv) + sizeof_priv,
625 SJA1000_ECHO_SKB_MAX);
626 if (!dev)
627 return NULL;
628
629 priv = netdev_priv(dev);
630
631 priv->dev = dev;
632 priv->can.bittiming_const = &sja1000_bittiming_const;
633 priv->can.do_set_bittiming = sja1000_set_bittiming;
634 priv->can.do_set_mode = sja1000_set_mode;
635 priv->can.do_get_berr_counter = sja1000_get_berr_counter;
636 priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK |
637 CAN_CTRLMODE_LISTENONLY |
638 CAN_CTRLMODE_3_SAMPLES |
639 CAN_CTRLMODE_ONE_SHOT |
640 CAN_CTRLMODE_BERR_REPORTING |
641 CAN_CTRLMODE_PRESUME_ACK;
642
643 spin_lock_init(&priv->cmdreg_lock);
644
645 if (sizeof_priv)
646 priv->priv = (void *)priv + sizeof(struct sja1000_priv);
647
648 return dev;
649 }
650 EXPORT_SYMBOL_GPL(alloc_sja1000dev);
651
652 void free_sja1000dev(struct net_device *dev)
653 {
654 free_candev(dev);
655 }
656 EXPORT_SYMBOL_GPL(free_sja1000dev);
657
658 static const struct net_device_ops sja1000_netdev_ops = {
659 .ndo_open = sja1000_open,
660 .ndo_stop = sja1000_close,
661 .ndo_start_xmit = sja1000_start_xmit,
662 .ndo_change_mtu = can_change_mtu,
663 };
664
665 int register_sja1000dev(struct net_device *dev)
666 {
667 int ret;
668
669 if (!sja1000_probe_chip(dev))
670 return -ENODEV;
671
672 dev->flags |= IFF_ECHO;
673 dev->netdev_ops = &sja1000_netdev_ops;
674
675 set_reset_mode(dev);
676 chipset_init(dev);
677
678 ret = register_candev(dev);
679
680 if (!ret)
681 devm_can_led_init(dev);
682
683 return ret;
684 }
685 EXPORT_SYMBOL_GPL(register_sja1000dev);
686
687 void unregister_sja1000dev(struct net_device *dev)
688 {
689 set_reset_mode(dev);
690 unregister_candev(dev);
691 }
692 EXPORT_SYMBOL_GPL(unregister_sja1000dev);
693
694 static __init int sja1000_init(void)
695 {
696 printk(KERN_INFO "%s CAN netdevice driver\n", DRV_NAME);
697
698 return 0;
699 }
700
701 module_init(sja1000_init);
702
703 static __exit void sja1000_exit(void)
704 {
705 printk(KERN_INFO "%s: driver removed\n", DRV_NAME);
706 }
707
708 module_exit(sja1000_exit);