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19#include <linux/signal.h>
20#include <linux/slab.h>
21#include <linux/module.h>
22#include <linux/netdevice.h>
23#include <linux/usb.h>
24
25#include <linux/can.h>
26#include <linux/can/dev.h>
27#include <linux/can/error.h>
28
29MODULE_AUTHOR("Sebastian Haas <haas@ems-wuensche.com>");
30MODULE_DESCRIPTION("CAN driver for EMS Dr. Thomas Wuensche CAN/USB interfaces");
31MODULE_LICENSE("GPL v2");
32
33
34#define CONTR_CAN_MESSAGE 0x04
35#define CONTR_CAN_STATE 0x0C
36#define CONTR_BUS_ERROR 0x1C
37
38
39#define CONTR_CONT_OFF 0
40#define CONTR_CONT_ON 1
41#define CONTR_ONCE 2
42
43
44#define CPC_MSG_TYPE_CAN_FRAME 1
45#define CPC_MSG_TYPE_RTR_FRAME 8
46#define CPC_MSG_TYPE_CAN_PARAMS 12
47#define CPC_MSG_TYPE_CAN_STATE 14
48#define CPC_MSG_TYPE_EXT_CAN_FRAME 16
49#define CPC_MSG_TYPE_EXT_RTR_FRAME 17
50#define CPC_MSG_TYPE_CONTROL 19
51#define CPC_MSG_TYPE_CONFIRM 20
52#define CPC_MSG_TYPE_OVERRUN 21
53#define CPC_MSG_TYPE_CAN_FRAME_ERROR 23
54#define CPC_MSG_TYPE_ERR_COUNTER 25
55
56
57#define CPC_CMD_TYPE_CAN_FRAME 1
58#define CPC_CMD_TYPE_CONTROL 3
59#define CPC_CMD_TYPE_CAN_PARAMS 6
60#define CPC_CMD_TYPE_RTR_FRAME 13
61#define CPC_CMD_TYPE_CAN_STATE 14
62#define CPC_CMD_TYPE_EXT_CAN_FRAME 15
63#define CPC_CMD_TYPE_EXT_RTR_FRAME 16
64#define CPC_CMD_TYPE_CAN_EXIT 200
65
66#define CPC_CMD_TYPE_INQ_ERR_COUNTER 25
67#define CPC_CMD_TYPE_CLEAR_MSG_QUEUE 8
68#define CPC_CMD_TYPE_CLEAR_CMD_QUEUE 28
69
70#define CPC_CC_TYPE_SJA1000 2
71
72#define CPC_CAN_ECODE_ERRFRAME 0x01
73
74
75#define CPC_OVR_EVENT_CAN 0x01
76#define CPC_OVR_EVENT_CANSTATE 0x02
77#define CPC_OVR_EVENT_BUSERROR 0x04
78
79
80
81
82
83#define CPC_OVR_HW 0x80
84
85
86#define CPC_MSG_HEADER_LEN 11
87#define CPC_CAN_MSG_MIN_SIZE 5
88
89
90#define USB_CPCUSB_VENDOR_ID 0x12D6
91
92#define USB_CPCUSB_ARM7_PRODUCT_ID 0x0444
93
94
95#define SJA1000_MOD_NORMAL 0x00
96#define SJA1000_MOD_RM 0x01
97
98
99#define SJA1000_ECC_SEG 0x1F
100#define SJA1000_ECC_DIR 0x20
101#define SJA1000_ECC_ERR 0x06
102#define SJA1000_ECC_BIT 0x00
103#define SJA1000_ECC_FORM 0x40
104#define SJA1000_ECC_STUFF 0x80
105#define SJA1000_ECC_MASK 0xc0
106
107
108#define SJA1000_SR_BS 0x80
109#define SJA1000_SR_ES 0x40
110
111#define SJA1000_DEFAULT_OUTPUT_CONTROL 0xDA
112
113
114
115
116
117
118#define EMS_USB_ARM7_CLOCK 8000000
119
120#define CPC_TX_QUEUE_TRIGGER_LOW 25
121#define CPC_TX_QUEUE_TRIGGER_HIGH 35
122
123
124
125
126
127
128struct cpc_can_msg {
129 __le32 id;
130 u8 length;
131 u8 msg[8];
132};
133
134
135struct cpc_sja1000_params {
136 u8 mode;
137 u8 acc_code0;
138 u8 acc_code1;
139 u8 acc_code2;
140 u8 acc_code3;
141 u8 acc_mask0;
142 u8 acc_mask1;
143 u8 acc_mask2;
144 u8 acc_mask3;
145 u8 btr0;
146 u8 btr1;
147 u8 outp_contr;
148};
149
150
151struct cpc_can_params {
152 u8 cc_type;
153
154
155 union {
156 struct cpc_sja1000_params sja1000;
157 } cc_params;
158};
159
160
161struct cpc_confirm {
162 u8 error;
163};
164
165
166struct cpc_overrun {
167 u8 event;
168 u8 count;
169};
170
171
172struct cpc_sja1000_can_error {
173 u8 ecc;
174 u8 rxerr;
175 u8 txerr;
176};
177
178
179struct cpc_can_error {
180 u8 ecode;
181
182 struct {
183 u8 cc_type;
184
185
186 union {
187 struct cpc_sja1000_can_error sja1000;
188 } regs;
189 } cc;
190};
191
192
193
194
195
196struct cpc_can_err_counter {
197 u8 rx;
198 u8 tx;
199};
200
201
202struct __packed ems_cpc_msg {
203 u8 type;
204 u8 length;
205 u8 msgid;
206 __le32 ts_sec;
207 __le32 ts_nsec;
208
209 union {
210 u8 generic[64];
211 struct cpc_can_msg can_msg;
212 struct cpc_can_params can_params;
213 struct cpc_confirm confirmation;
214 struct cpc_overrun overrun;
215 struct cpc_can_error error;
216 struct cpc_can_err_counter err_counter;
217 u8 can_state;
218 } msg;
219};
220
221
222
223
224
225static struct usb_device_id ems_usb_table[] = {
226 {USB_DEVICE(USB_CPCUSB_VENDOR_ID, USB_CPCUSB_ARM7_PRODUCT_ID)},
227 {}
228};
229
230MODULE_DEVICE_TABLE(usb, ems_usb_table);
231
232#define RX_BUFFER_SIZE 64
233#define CPC_HEADER_SIZE 4
234#define INTR_IN_BUFFER_SIZE 4
235
236#define MAX_RX_URBS 10
237#define MAX_TX_URBS 10
238
239struct ems_usb;
240
241struct ems_tx_urb_context {
242 struct ems_usb *dev;
243
244 u32 echo_index;
245 u8 dlc;
246};
247
248struct ems_usb {
249 struct can_priv can;
250
251 struct sk_buff *echo_skb[MAX_TX_URBS];
252
253 struct usb_device *udev;
254 struct net_device *netdev;
255
256 atomic_t active_tx_urbs;
257 struct usb_anchor tx_submitted;
258 struct ems_tx_urb_context tx_contexts[MAX_TX_URBS];
259
260 struct usb_anchor rx_submitted;
261
262 struct urb *intr_urb;
263
264 u8 *tx_msg_buffer;
265
266 u8 *intr_in_buffer;
267 unsigned int free_slots;
268
269 struct ems_cpc_msg active_params;
270};
271
272static void ems_usb_read_interrupt_callback(struct urb *urb)
273{
274 struct ems_usb *dev = urb->context;
275 struct net_device *netdev = dev->netdev;
276 int err;
277
278 if (!netif_device_present(netdev))
279 return;
280
281 switch (urb->status) {
282 case 0:
283 dev->free_slots = dev->intr_in_buffer[1];
284 if (dev->free_slots > CPC_TX_QUEUE_TRIGGER_HIGH &&
285 netif_queue_stopped(netdev))
286 netif_wake_queue(netdev);
287 break;
288
289 case -ECONNRESET:
290 case -ENOENT:
291 case -EPIPE:
292 case -EPROTO:
293 case -ESHUTDOWN:
294 return;
295
296 default:
297 netdev_info(netdev, "Rx interrupt aborted %d\n", urb->status);
298 break;
299 }
300
301 err = usb_submit_urb(urb, GFP_ATOMIC);
302
303 if (err == -ENODEV)
304 netif_device_detach(netdev);
305 else if (err)
306 netdev_err(netdev, "failed resubmitting intr urb: %d\n", err);
307}
308
309static void ems_usb_rx_can_msg(struct ems_usb *dev, struct ems_cpc_msg *msg)
310{
311 struct can_frame *cf;
312 struct sk_buff *skb;
313 int i;
314 struct net_device_stats *stats = &dev->netdev->stats;
315
316 skb = alloc_can_skb(dev->netdev, &cf);
317 if (skb == NULL)
318 return;
319
320 cf->can_id = le32_to_cpu(msg->msg.can_msg.id);
321 cf->can_dlc = get_can_dlc(msg->msg.can_msg.length & 0xF);
322
323 if (msg->type == CPC_MSG_TYPE_EXT_CAN_FRAME ||
324 msg->type == CPC_MSG_TYPE_EXT_RTR_FRAME)
325 cf->can_id |= CAN_EFF_FLAG;
326
327 if (msg->type == CPC_MSG_TYPE_RTR_FRAME ||
328 msg->type == CPC_MSG_TYPE_EXT_RTR_FRAME) {
329 cf->can_id |= CAN_RTR_FLAG;
330 } else {
331 for (i = 0; i < cf->can_dlc; i++)
332 cf->data[i] = msg->msg.can_msg.msg[i];
333 }
334
335 stats->rx_packets++;
336 stats->rx_bytes += cf->can_dlc;
337 netif_rx(skb);
338}
339
340static void ems_usb_rx_err(struct ems_usb *dev, struct ems_cpc_msg *msg)
341{
342 struct can_frame *cf;
343 struct sk_buff *skb;
344 struct net_device_stats *stats = &dev->netdev->stats;
345
346 skb = alloc_can_err_skb(dev->netdev, &cf);
347 if (skb == NULL)
348 return;
349
350 if (msg->type == CPC_MSG_TYPE_CAN_STATE) {
351 u8 state = msg->msg.can_state;
352
353 if (state & SJA1000_SR_BS) {
354 dev->can.state = CAN_STATE_BUS_OFF;
355 cf->can_id |= CAN_ERR_BUSOFF;
356
357 dev->can.can_stats.bus_off++;
358 can_bus_off(dev->netdev);
359 } else if (state & SJA1000_SR_ES) {
360 dev->can.state = CAN_STATE_ERROR_WARNING;
361 dev->can.can_stats.error_warning++;
362 } else {
363 dev->can.state = CAN_STATE_ERROR_ACTIVE;
364 dev->can.can_stats.error_passive++;
365 }
366 } else if (msg->type == CPC_MSG_TYPE_CAN_FRAME_ERROR) {
367 u8 ecc = msg->msg.error.cc.regs.sja1000.ecc;
368 u8 txerr = msg->msg.error.cc.regs.sja1000.txerr;
369 u8 rxerr = msg->msg.error.cc.regs.sja1000.rxerr;
370
371
372 dev->can.can_stats.bus_error++;
373 stats->rx_errors++;
374
375 cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
376
377 switch (ecc & SJA1000_ECC_MASK) {
378 case SJA1000_ECC_BIT:
379 cf->data[2] |= CAN_ERR_PROT_BIT;
380 break;
381 case SJA1000_ECC_FORM:
382 cf->data[2] |= CAN_ERR_PROT_FORM;
383 break;
384 case SJA1000_ECC_STUFF:
385 cf->data[2] |= CAN_ERR_PROT_STUFF;
386 break;
387 default:
388 cf->data[3] = ecc & SJA1000_ECC_SEG;
389 break;
390 }
391
392
393 if ((ecc & SJA1000_ECC_DIR) == 0)
394 cf->data[2] |= CAN_ERR_PROT_TX;
395
396 if (dev->can.state == CAN_STATE_ERROR_WARNING ||
397 dev->can.state == CAN_STATE_ERROR_PASSIVE) {
398 cf->can_id |= CAN_ERR_CRTL;
399 cf->data[1] = (txerr > rxerr) ?
400 CAN_ERR_CRTL_TX_PASSIVE : CAN_ERR_CRTL_RX_PASSIVE;
401 }
402 } else if (msg->type == CPC_MSG_TYPE_OVERRUN) {
403 cf->can_id |= CAN_ERR_CRTL;
404 cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
405
406 stats->rx_over_errors++;
407 stats->rx_errors++;
408 }
409
410 stats->rx_packets++;
411 stats->rx_bytes += cf->can_dlc;
412 netif_rx(skb);
413}
414
415
416
417
418static void ems_usb_read_bulk_callback(struct urb *urb)
419{
420 struct ems_usb *dev = urb->context;
421 struct net_device *netdev;
422 int retval;
423
424 netdev = dev->netdev;
425
426 if (!netif_device_present(netdev))
427 return;
428
429 switch (urb->status) {
430 case 0:
431 break;
432
433 case -ENOENT:
434 return;
435
436 default:
437 netdev_info(netdev, "Rx URB aborted (%d)\n", urb->status);
438 goto resubmit_urb;
439 }
440
441 if (urb->actual_length > CPC_HEADER_SIZE) {
442 struct ems_cpc_msg *msg;
443 u8 *ibuf = urb->transfer_buffer;
444 u8 msg_count, start;
445
446 msg_count = ibuf[0] & ~0x80;
447
448 start = CPC_HEADER_SIZE;
449
450 while (msg_count) {
451 msg = (struct ems_cpc_msg *)&ibuf[start];
452
453 switch (msg->type) {
454 case CPC_MSG_TYPE_CAN_STATE:
455
456 ems_usb_rx_err(dev, msg);
457 break;
458
459 case CPC_MSG_TYPE_CAN_FRAME:
460 case CPC_MSG_TYPE_EXT_CAN_FRAME:
461 case CPC_MSG_TYPE_RTR_FRAME:
462 case CPC_MSG_TYPE_EXT_RTR_FRAME:
463 ems_usb_rx_can_msg(dev, msg);
464 break;
465
466 case CPC_MSG_TYPE_CAN_FRAME_ERROR:
467
468 ems_usb_rx_err(dev, msg);
469 break;
470
471 case CPC_MSG_TYPE_OVERRUN:
472
473 ems_usb_rx_err(dev, msg);
474 break;
475 }
476
477 start += CPC_MSG_HEADER_LEN + msg->length;
478 msg_count--;
479
480 if (start > urb->transfer_buffer_length) {
481 netdev_err(netdev, "format error\n");
482 break;
483 }
484 }
485 }
486
487resubmit_urb:
488 usb_fill_bulk_urb(urb, dev->udev, usb_rcvbulkpipe(dev->udev, 2),
489 urb->transfer_buffer, RX_BUFFER_SIZE,
490 ems_usb_read_bulk_callback, dev);
491
492 retval = usb_submit_urb(urb, GFP_ATOMIC);
493
494 if (retval == -ENODEV)
495 netif_device_detach(netdev);
496 else if (retval)
497 netdev_err(netdev,
498 "failed resubmitting read bulk urb: %d\n", retval);
499}
500
501
502
503
504static void ems_usb_write_bulk_callback(struct urb *urb)
505{
506 struct ems_tx_urb_context *context = urb->context;
507 struct ems_usb *dev;
508 struct net_device *netdev;
509
510 BUG_ON(!context);
511
512 dev = context->dev;
513 netdev = dev->netdev;
514
515
516 usb_free_coherent(urb->dev, urb->transfer_buffer_length,
517 urb->transfer_buffer, urb->transfer_dma);
518
519 atomic_dec(&dev->active_tx_urbs);
520
521 if (!netif_device_present(netdev))
522 return;
523
524 if (urb->status)
525 netdev_info(netdev, "Tx URB aborted (%d)\n", urb->status);
526
527 netif_trans_update(netdev);
528
529
530 netdev->stats.tx_packets++;
531 netdev->stats.tx_bytes += context->dlc;
532
533 can_get_echo_skb(netdev, context->echo_index);
534
535
536 context->echo_index = MAX_TX_URBS;
537
538}
539
540
541
542
543static int ems_usb_command_msg(struct ems_usb *dev, struct ems_cpc_msg *msg)
544{
545 int actual_length;
546
547
548 memcpy(&dev->tx_msg_buffer[CPC_HEADER_SIZE], msg,
549 msg->length + CPC_MSG_HEADER_LEN);
550
551
552 memset(&dev->tx_msg_buffer[0], 0, CPC_HEADER_SIZE);
553
554 return usb_bulk_msg(dev->udev, usb_sndbulkpipe(dev->udev, 2),
555 &dev->tx_msg_buffer[0],
556 msg->length + CPC_MSG_HEADER_LEN + CPC_HEADER_SIZE,
557 &actual_length, 1000);
558}
559
560
561
562
563static int ems_usb_write_mode(struct ems_usb *dev, u8 mode)
564{
565 dev->active_params.msg.can_params.cc_params.sja1000.mode = mode;
566
567 return ems_usb_command_msg(dev, &dev->active_params);
568}
569
570
571
572
573
574static int ems_usb_control_cmd(struct ems_usb *dev, u8 val)
575{
576 struct ems_cpc_msg cmd;
577
578 cmd.type = CPC_CMD_TYPE_CONTROL;
579 cmd.length = CPC_MSG_HEADER_LEN + 1;
580
581 cmd.msgid = 0;
582
583 cmd.msg.generic[0] = val;
584
585 return ems_usb_command_msg(dev, &cmd);
586}
587
588
589
590
591static int ems_usb_start(struct ems_usb *dev)
592{
593 struct net_device *netdev = dev->netdev;
594 int err, i;
595
596 dev->intr_in_buffer[0] = 0;
597 dev->free_slots = 50;
598
599 for (i = 0; i < MAX_RX_URBS; i++) {
600 struct urb *urb = NULL;
601 u8 *buf = NULL;
602
603
604 urb = usb_alloc_urb(0, GFP_KERNEL);
605 if (!urb) {
606 err = -ENOMEM;
607 break;
608 }
609
610 buf = usb_alloc_coherent(dev->udev, RX_BUFFER_SIZE, GFP_KERNEL,
611 &urb->transfer_dma);
612 if (!buf) {
613 netdev_err(netdev, "No memory left for USB buffer\n");
614 usb_free_urb(urb);
615 err = -ENOMEM;
616 break;
617 }
618
619 usb_fill_bulk_urb(urb, dev->udev, usb_rcvbulkpipe(dev->udev, 2),
620 buf, RX_BUFFER_SIZE,
621 ems_usb_read_bulk_callback, dev);
622 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
623 usb_anchor_urb(urb, &dev->rx_submitted);
624
625 err = usb_submit_urb(urb, GFP_KERNEL);
626 if (err) {
627 usb_unanchor_urb(urb);
628 usb_free_coherent(dev->udev, RX_BUFFER_SIZE, buf,
629 urb->transfer_dma);
630 usb_free_urb(urb);
631 break;
632 }
633
634
635 usb_free_urb(urb);
636 }
637
638
639 if (i == 0) {
640 netdev_warn(netdev, "couldn't setup read URBs\n");
641 return err;
642 }
643
644
645 if (i < MAX_RX_URBS)
646 netdev_warn(netdev, "rx performance may be slow\n");
647
648
649 usb_fill_int_urb(dev->intr_urb, dev->udev,
650 usb_rcvintpipe(dev->udev, 1),
651 dev->intr_in_buffer,
652 INTR_IN_BUFFER_SIZE,
653 ems_usb_read_interrupt_callback, dev, 1);
654
655 err = usb_submit_urb(dev->intr_urb, GFP_KERNEL);
656 if (err) {
657 netdev_warn(netdev, "intr URB submit failed: %d\n", err);
658
659 return err;
660 }
661
662
663 err = ems_usb_control_cmd(dev, CONTR_CAN_MESSAGE | CONTR_CONT_ON);
664 if (err)
665 goto failed;
666
667
668 err = ems_usb_control_cmd(dev, CONTR_CAN_STATE | CONTR_CONT_ON);
669 if (err)
670 goto failed;
671
672
673 err = ems_usb_control_cmd(dev, CONTR_BUS_ERROR | CONTR_CONT_ON);
674 if (err)
675 goto failed;
676
677 err = ems_usb_write_mode(dev, SJA1000_MOD_NORMAL);
678 if (err)
679 goto failed;
680
681 dev->can.state = CAN_STATE_ERROR_ACTIVE;
682
683 return 0;
684
685failed:
686 netdev_warn(netdev, "couldn't submit control: %d\n", err);
687
688 return err;
689}
690
691static void unlink_all_urbs(struct ems_usb *dev)
692{
693 int i;
694
695 usb_unlink_urb(dev->intr_urb);
696
697 usb_kill_anchored_urbs(&dev->rx_submitted);
698
699 usb_kill_anchored_urbs(&dev->tx_submitted);
700 atomic_set(&dev->active_tx_urbs, 0);
701
702 for (i = 0; i < MAX_TX_URBS; i++)
703 dev->tx_contexts[i].echo_index = MAX_TX_URBS;
704}
705
706static int ems_usb_open(struct net_device *netdev)
707{
708 struct ems_usb *dev = netdev_priv(netdev);
709 int err;
710
711 err = ems_usb_write_mode(dev, SJA1000_MOD_RM);
712 if (err)
713 return err;
714
715
716 err = open_candev(netdev);
717 if (err)
718 return err;
719
720
721 err = ems_usb_start(dev);
722 if (err) {
723 if (err == -ENODEV)
724 netif_device_detach(dev->netdev);
725
726 netdev_warn(netdev, "couldn't start device: %d\n", err);
727
728 close_candev(netdev);
729
730 return err;
731 }
732
733
734 netif_start_queue(netdev);
735
736 return 0;
737}
738
739static netdev_tx_t ems_usb_start_xmit(struct sk_buff *skb, struct net_device *netdev)
740{
741 struct ems_usb *dev = netdev_priv(netdev);
742 struct ems_tx_urb_context *context = NULL;
743 struct net_device_stats *stats = &netdev->stats;
744 struct can_frame *cf = (struct can_frame *)skb->data;
745 struct ems_cpc_msg *msg;
746 struct urb *urb;
747 u8 *buf;
748 int i, err;
749 size_t size = CPC_HEADER_SIZE + CPC_MSG_HEADER_LEN
750 + sizeof(struct cpc_can_msg);
751
752 if (can_dropped_invalid_skb(netdev, skb))
753 return NETDEV_TX_OK;
754
755
756 urb = usb_alloc_urb(0, GFP_ATOMIC);
757 if (!urb)
758 goto nomem;
759
760 buf = usb_alloc_coherent(dev->udev, size, GFP_ATOMIC, &urb->transfer_dma);
761 if (!buf) {
762 netdev_err(netdev, "No memory left for USB buffer\n");
763 usb_free_urb(urb);
764 goto nomem;
765 }
766
767 msg = (struct ems_cpc_msg *)&buf[CPC_HEADER_SIZE];
768
769 msg->msg.can_msg.id = cpu_to_le32(cf->can_id & CAN_ERR_MASK);
770 msg->msg.can_msg.length = cf->can_dlc;
771
772 if (cf->can_id & CAN_RTR_FLAG) {
773 msg->type = cf->can_id & CAN_EFF_FLAG ?
774 CPC_CMD_TYPE_EXT_RTR_FRAME : CPC_CMD_TYPE_RTR_FRAME;
775
776 msg->length = CPC_CAN_MSG_MIN_SIZE;
777 } else {
778 msg->type = cf->can_id & CAN_EFF_FLAG ?
779 CPC_CMD_TYPE_EXT_CAN_FRAME : CPC_CMD_TYPE_CAN_FRAME;
780
781 for (i = 0; i < cf->can_dlc; i++)
782 msg->msg.can_msg.msg[i] = cf->data[i];
783
784 msg->length = CPC_CAN_MSG_MIN_SIZE + cf->can_dlc;
785 }
786
787 for (i = 0; i < MAX_TX_URBS; i++) {
788 if (dev->tx_contexts[i].echo_index == MAX_TX_URBS) {
789 context = &dev->tx_contexts[i];
790 break;
791 }
792 }
793
794
795
796
797
798 if (!context) {
799 usb_free_coherent(dev->udev, size, buf, urb->transfer_dma);
800 usb_free_urb(urb);
801
802 netdev_warn(netdev, "couldn't find free context\n");
803
804 return NETDEV_TX_BUSY;
805 }
806
807 context->dev = dev;
808 context->echo_index = i;
809 context->dlc = cf->can_dlc;
810
811 usb_fill_bulk_urb(urb, dev->udev, usb_sndbulkpipe(dev->udev, 2), buf,
812 size, ems_usb_write_bulk_callback, context);
813 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
814 usb_anchor_urb(urb, &dev->tx_submitted);
815
816 can_put_echo_skb(skb, netdev, context->echo_index);
817
818 atomic_inc(&dev->active_tx_urbs);
819
820 err = usb_submit_urb(urb, GFP_ATOMIC);
821 if (unlikely(err)) {
822 can_free_echo_skb(netdev, context->echo_index);
823
824 usb_unanchor_urb(urb);
825 usb_free_coherent(dev->udev, size, buf, urb->transfer_dma);
826 dev_kfree_skb(skb);
827
828 atomic_dec(&dev->active_tx_urbs);
829
830 if (err == -ENODEV) {
831 netif_device_detach(netdev);
832 } else {
833 netdev_warn(netdev, "failed tx_urb %d\n", err);
834
835 stats->tx_dropped++;
836 }
837 } else {
838 netif_trans_update(netdev);
839
840
841 if (atomic_read(&dev->active_tx_urbs) >= MAX_TX_URBS ||
842 dev->free_slots < CPC_TX_QUEUE_TRIGGER_LOW) {
843 netif_stop_queue(netdev);
844 }
845 }
846
847
848
849
850
851 usb_free_urb(urb);
852
853 return NETDEV_TX_OK;
854
855nomem:
856 dev_kfree_skb(skb);
857 stats->tx_dropped++;
858
859 return NETDEV_TX_OK;
860}
861
862static int ems_usb_close(struct net_device *netdev)
863{
864 struct ems_usb *dev = netdev_priv(netdev);
865
866
867 unlink_all_urbs(dev);
868
869 netif_stop_queue(netdev);
870
871
872 if (ems_usb_write_mode(dev, SJA1000_MOD_RM))
873 netdev_warn(netdev, "couldn't stop device");
874
875 close_candev(netdev);
876
877 return 0;
878}
879
880static const struct net_device_ops ems_usb_netdev_ops = {
881 .ndo_open = ems_usb_open,
882 .ndo_stop = ems_usb_close,
883 .ndo_start_xmit = ems_usb_start_xmit,
884 .ndo_change_mtu = can_change_mtu,
885};
886
887static const struct can_bittiming_const ems_usb_bittiming_const = {
888 .name = "ems_usb",
889 .tseg1_min = 1,
890 .tseg1_max = 16,
891 .tseg2_min = 1,
892 .tseg2_max = 8,
893 .sjw_max = 4,
894 .brp_min = 1,
895 .brp_max = 64,
896 .brp_inc = 1,
897};
898
899static int ems_usb_set_mode(struct net_device *netdev, enum can_mode mode)
900{
901 struct ems_usb *dev = netdev_priv(netdev);
902
903 switch (mode) {
904 case CAN_MODE_START:
905 if (ems_usb_write_mode(dev, SJA1000_MOD_NORMAL))
906 netdev_warn(netdev, "couldn't start device");
907
908 if (netif_queue_stopped(netdev))
909 netif_wake_queue(netdev);
910 break;
911
912 default:
913 return -EOPNOTSUPP;
914 }
915
916 return 0;
917}
918
919static int ems_usb_set_bittiming(struct net_device *netdev)
920{
921 struct ems_usb *dev = netdev_priv(netdev);
922 struct can_bittiming *bt = &dev->can.bittiming;
923 u8 btr0, btr1;
924
925 btr0 = ((bt->brp - 1) & 0x3f) | (((bt->sjw - 1) & 0x3) << 6);
926 btr1 = ((bt->prop_seg + bt->phase_seg1 - 1) & 0xf) |
927 (((bt->phase_seg2 - 1) & 0x7) << 4);
928 if (dev->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
929 btr1 |= 0x80;
930
931 netdev_info(netdev, "setting BTR0=0x%02x BTR1=0x%02x\n", btr0, btr1);
932
933 dev->active_params.msg.can_params.cc_params.sja1000.btr0 = btr0;
934 dev->active_params.msg.can_params.cc_params.sja1000.btr1 = btr1;
935
936 return ems_usb_command_msg(dev, &dev->active_params);
937}
938
939static void init_params_sja1000(struct ems_cpc_msg *msg)
940{
941 struct cpc_sja1000_params *sja1000 =
942 &msg->msg.can_params.cc_params.sja1000;
943
944 msg->type = CPC_CMD_TYPE_CAN_PARAMS;
945 msg->length = sizeof(struct cpc_can_params);
946 msg->msgid = 0;
947
948 msg->msg.can_params.cc_type = CPC_CC_TYPE_SJA1000;
949
950
951 sja1000->acc_code0 = 0x00;
952 sja1000->acc_code1 = 0x00;
953 sja1000->acc_code2 = 0x00;
954 sja1000->acc_code3 = 0x00;
955
956
957 sja1000->acc_mask0 = 0xFF;
958 sja1000->acc_mask1 = 0xFF;
959 sja1000->acc_mask2 = 0xFF;
960 sja1000->acc_mask3 = 0xFF;
961
962 sja1000->btr0 = 0;
963 sja1000->btr1 = 0;
964
965 sja1000->outp_contr = SJA1000_DEFAULT_OUTPUT_CONTROL;
966 sja1000->mode = SJA1000_MOD_RM;
967}
968
969
970
971
972static int ems_usb_probe(struct usb_interface *intf,
973 const struct usb_device_id *id)
974{
975 struct net_device *netdev;
976 struct ems_usb *dev;
977 int i, err = -ENOMEM;
978
979 netdev = alloc_candev(sizeof(struct ems_usb), MAX_TX_URBS);
980 if (!netdev) {
981 dev_err(&intf->dev, "ems_usb: Couldn't alloc candev\n");
982 return -ENOMEM;
983 }
984
985 dev = netdev_priv(netdev);
986
987 dev->udev = interface_to_usbdev(intf);
988 dev->netdev = netdev;
989
990 dev->can.state = CAN_STATE_STOPPED;
991 dev->can.clock.freq = EMS_USB_ARM7_CLOCK;
992 dev->can.bittiming_const = &ems_usb_bittiming_const;
993 dev->can.do_set_bittiming = ems_usb_set_bittiming;
994 dev->can.do_set_mode = ems_usb_set_mode;
995 dev->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES;
996
997 netdev->netdev_ops = &ems_usb_netdev_ops;
998
999 netdev->flags |= IFF_ECHO;
1000
1001 init_usb_anchor(&dev->rx_submitted);
1002
1003 init_usb_anchor(&dev->tx_submitted);
1004 atomic_set(&dev->active_tx_urbs, 0);
1005
1006 for (i = 0; i < MAX_TX_URBS; i++)
1007 dev->tx_contexts[i].echo_index = MAX_TX_URBS;
1008
1009 dev->intr_urb = usb_alloc_urb(0, GFP_KERNEL);
1010 if (!dev->intr_urb)
1011 goto cleanup_candev;
1012
1013 dev->intr_in_buffer = kzalloc(INTR_IN_BUFFER_SIZE, GFP_KERNEL);
1014 if (!dev->intr_in_buffer)
1015 goto cleanup_intr_urb;
1016
1017 dev->tx_msg_buffer = kzalloc(CPC_HEADER_SIZE +
1018 sizeof(struct ems_cpc_msg), GFP_KERNEL);
1019 if (!dev->tx_msg_buffer)
1020 goto cleanup_intr_in_buffer;
1021
1022 usb_set_intfdata(intf, dev);
1023
1024 SET_NETDEV_DEV(netdev, &intf->dev);
1025
1026 init_params_sja1000(&dev->active_params);
1027
1028 err = ems_usb_command_msg(dev, &dev->active_params);
1029 if (err) {
1030 netdev_err(netdev, "couldn't initialize controller: %d\n", err);
1031 goto cleanup_tx_msg_buffer;
1032 }
1033
1034 err = register_candev(netdev);
1035 if (err) {
1036 netdev_err(netdev, "couldn't register CAN device: %d\n", err);
1037 goto cleanup_tx_msg_buffer;
1038 }
1039
1040 return 0;
1041
1042cleanup_tx_msg_buffer:
1043 kfree(dev->tx_msg_buffer);
1044
1045cleanup_intr_in_buffer:
1046 kfree(dev->intr_in_buffer);
1047
1048cleanup_intr_urb:
1049 usb_free_urb(dev->intr_urb);
1050
1051cleanup_candev:
1052 free_candev(netdev);
1053
1054 return err;
1055}
1056
1057
1058
1059
1060static void ems_usb_disconnect(struct usb_interface *intf)
1061{
1062 struct ems_usb *dev = usb_get_intfdata(intf);
1063
1064 usb_set_intfdata(intf, NULL);
1065
1066 if (dev) {
1067 unregister_netdev(dev->netdev);
1068 free_candev(dev->netdev);
1069
1070 unlink_all_urbs(dev);
1071
1072 usb_free_urb(dev->intr_urb);
1073
1074 kfree(dev->intr_in_buffer);
1075 kfree(dev->tx_msg_buffer);
1076 }
1077}
1078
1079
1080static struct usb_driver ems_usb_driver = {
1081 .name = "ems_usb",
1082 .probe = ems_usb_probe,
1083 .disconnect = ems_usb_disconnect,
1084 .id_table = ems_usb_table,
1085};
1086
1087module_usb_driver(ems_usb_driver);
1088