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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * CAN driver for "8 devices" USB2CAN converter
4 *
5 * Copyright (C) 2012 Bernd Krumboeck (krumboeck@universalnet.at)
6 *
7 * This driver is inspired by the 3.2.0 version of drivers/net/can/usb/ems_usb.c
8 * and drivers/net/can/usb/esd_usb2.c
9 *
10 * Many thanks to Gerhard Bertelsmann (info@gerhard-bertelsmann.de)
11 * for testing and fixing this driver. Also many thanks to "8 devices",
12 * who were very cooperative and answered my questions.
13 */
14
15#include <linux/ethtool.h>
16#include <linux/signal.h>
17#include <linux/slab.h>
18#include <linux/module.h>
19#include <linux/netdevice.h>
20#include <linux/usb.h>
21
22#include <linux/can.h>
23#include <linux/can/dev.h>
24#include <linux/can/error.h>
25
26/* driver constants */
27#define MAX_RX_URBS 20
28#define MAX_TX_URBS 20
29#define RX_BUFFER_SIZE 64
30
31/* vendor and product id */
32#define USB_8DEV_VENDOR_ID 0x0483
33#define USB_8DEV_PRODUCT_ID 0x1234
34
35/* endpoints */
36enum usb_8dev_endpoint {
37 USB_8DEV_ENDP_DATA_RX = 1,
38 USB_8DEV_ENDP_DATA_TX,
39 USB_8DEV_ENDP_CMD_RX,
40 USB_8DEV_ENDP_CMD_TX
41};
42
43/* device CAN clock */
44#define USB_8DEV_ABP_CLOCK 32000000
45
46/* setup flags */
47#define USB_8DEV_SILENT 0x01
48#define USB_8DEV_LOOPBACK 0x02
49#define USB_8DEV_DISABLE_AUTO_RESTRANS 0x04
50#define USB_8DEV_STATUS_FRAME 0x08
51
52/* commands */
53enum usb_8dev_cmd {
54 USB_8DEV_RESET = 1,
55 USB_8DEV_OPEN,
56 USB_8DEV_CLOSE,
57 USB_8DEV_SET_SPEED,
58 USB_8DEV_SET_MASK_FILTER,
59 USB_8DEV_GET_STATUS,
60 USB_8DEV_GET_STATISTICS,
61 USB_8DEV_GET_SERIAL,
62 USB_8DEV_GET_SOFTW_VER,
63 USB_8DEV_GET_HARDW_VER,
64 USB_8DEV_RESET_TIMESTAMP,
65 USB_8DEV_GET_SOFTW_HARDW_VER
66};
67
68/* command options */
69#define USB_8DEV_BAUD_MANUAL 0x09
70#define USB_8DEV_CMD_START 0x11
71#define USB_8DEV_CMD_END 0x22
72
73#define USB_8DEV_CMD_SUCCESS 0
74#define USB_8DEV_CMD_ERROR 255
75
76#define USB_8DEV_CMD_TIMEOUT 1000
77
78/* frames */
79#define USB_8DEV_DATA_START 0x55
80#define USB_8DEV_DATA_END 0xAA
81
82#define USB_8DEV_TYPE_CAN_FRAME 0
83#define USB_8DEV_TYPE_ERROR_FRAME 3
84
85#define USB_8DEV_EXTID 0x01
86#define USB_8DEV_RTR 0x02
87#define USB_8DEV_ERR_FLAG 0x04
88
89/* status */
90#define USB_8DEV_STATUSMSG_OK 0x00 /* Normal condition. */
91#define USB_8DEV_STATUSMSG_OVERRUN 0x01 /* Overrun occurred when sending */
92#define USB_8DEV_STATUSMSG_BUSLIGHT 0x02 /* Error counter has reached 96 */
93#define USB_8DEV_STATUSMSG_BUSHEAVY 0x03 /* Error count. has reached 128 */
94#define USB_8DEV_STATUSMSG_BUSOFF 0x04 /* Device is in BUSOFF */
95#define USB_8DEV_STATUSMSG_STUFF 0x20 /* Stuff Error */
96#define USB_8DEV_STATUSMSG_FORM 0x21 /* Form Error */
97#define USB_8DEV_STATUSMSG_ACK 0x23 /* Ack Error */
98#define USB_8DEV_STATUSMSG_BIT0 0x24 /* Bit1 Error */
99#define USB_8DEV_STATUSMSG_BIT1 0x25 /* Bit0 Error */
100#define USB_8DEV_STATUSMSG_CRC 0x27 /* CRC Error */
101
102#define USB_8DEV_RP_MASK 0x7F /* Mask for Receive Error Bit */
103
104
105/* table of devices that work with this driver */
106static const struct usb_device_id usb_8dev_table[] = {
107 { USB_DEVICE(USB_8DEV_VENDOR_ID, USB_8DEV_PRODUCT_ID) },
108 { } /* Terminating entry */
109};
110
111MODULE_DEVICE_TABLE(usb, usb_8dev_table);
112
113struct usb_8dev_tx_urb_context {
114 struct usb_8dev_priv *priv;
115
116 u32 echo_index;
117};
118
119/* Structure to hold all of our device specific stuff */
120struct usb_8dev_priv {
121 struct can_priv can; /* must be the first member */
122
123 struct usb_device *udev;
124 struct net_device *netdev;
125
126 atomic_t active_tx_urbs;
127 struct usb_anchor tx_submitted;
128 struct usb_8dev_tx_urb_context tx_contexts[MAX_TX_URBS];
129
130 struct usb_anchor rx_submitted;
131
132 struct can_berr_counter bec;
133
134 u8 *cmd_msg_buffer;
135
136 struct mutex usb_8dev_cmd_lock;
137 void *rxbuf[MAX_RX_URBS];
138 dma_addr_t rxbuf_dma[MAX_RX_URBS];
139};
140
141/* tx frame */
142struct __packed usb_8dev_tx_msg {
143 u8 begin;
144 u8 flags; /* RTR and EXT_ID flag */
145 __be32 id; /* upper 3 bits not used */
146 u8 dlc; /* data length code 0-8 bytes */
147 u8 data[8]; /* 64-bit data */
148 u8 end;
149};
150
151/* rx frame */
152struct __packed usb_8dev_rx_msg {
153 u8 begin;
154 u8 type; /* frame type */
155 u8 flags; /* RTR and EXT_ID flag */
156 __be32 id; /* upper 3 bits not used */
157 u8 dlc; /* data length code 0-8 bytes */
158 u8 data[8]; /* 64-bit data */
159 __be32 timestamp; /* 32-bit timestamp */
160 u8 end;
161};
162
163/* command frame */
164struct __packed usb_8dev_cmd_msg {
165 u8 begin;
166 u8 channel; /* unknown - always 0 */
167 u8 command; /* command to execute */
168 u8 opt1; /* optional parameter / return value */
169 u8 opt2; /* optional parameter 2 */
170 u8 data[10]; /* optional parameter and data */
171 u8 end;
172};
173
174static int usb_8dev_send_cmd_msg(struct usb_8dev_priv *priv, u8 *msg, int size)
175{
176 int actual_length;
177
178 return usb_bulk_msg(priv->udev,
179 usb_sndbulkpipe(priv->udev, USB_8DEV_ENDP_CMD_TX),
180 msg, size, &actual_length, USB_8DEV_CMD_TIMEOUT);
181}
182
183static int usb_8dev_wait_cmd_msg(struct usb_8dev_priv *priv, u8 *msg, int size,
184 int *actual_length)
185{
186 return usb_bulk_msg(priv->udev,
187 usb_rcvbulkpipe(priv->udev, USB_8DEV_ENDP_CMD_RX),
188 msg, size, actual_length, USB_8DEV_CMD_TIMEOUT);
189}
190
191/* Send command to device and receive result.
192 * Command was successful when opt1 = 0.
193 */
194static int usb_8dev_send_cmd(struct usb_8dev_priv *priv,
195 struct usb_8dev_cmd_msg *out,
196 struct usb_8dev_cmd_msg *in)
197{
198 int err;
199 int num_bytes_read;
200 struct net_device *netdev;
201
202 netdev = priv->netdev;
203
204 out->begin = USB_8DEV_CMD_START;
205 out->end = USB_8DEV_CMD_END;
206
207 mutex_lock(&priv->usb_8dev_cmd_lock);
208
209 memcpy(priv->cmd_msg_buffer, out,
210 sizeof(struct usb_8dev_cmd_msg));
211
212 err = usb_8dev_send_cmd_msg(priv, priv->cmd_msg_buffer,
213 sizeof(struct usb_8dev_cmd_msg));
214 if (err < 0) {
215 netdev_err(netdev, "sending command message failed\n");
216 goto failed;
217 }
218
219 err = usb_8dev_wait_cmd_msg(priv, priv->cmd_msg_buffer,
220 sizeof(struct usb_8dev_cmd_msg),
221 &num_bytes_read);
222 if (err < 0) {
223 netdev_err(netdev, "no command message answer\n");
224 goto failed;
225 }
226
227 memcpy(in, priv->cmd_msg_buffer, sizeof(struct usb_8dev_cmd_msg));
228
229 if (in->begin != USB_8DEV_CMD_START || in->end != USB_8DEV_CMD_END ||
230 num_bytes_read != 16 || in->opt1 != 0)
231 err = -EPROTO;
232
233failed:
234 mutex_unlock(&priv->usb_8dev_cmd_lock);
235 return err;
236}
237
238/* Send open command to device */
239static int usb_8dev_cmd_open(struct usb_8dev_priv *priv)
240{
241 struct can_bittiming *bt = &priv->can.bittiming;
242 struct usb_8dev_cmd_msg outmsg;
243 struct usb_8dev_cmd_msg inmsg;
244 u32 ctrlmode = priv->can.ctrlmode;
245 u32 flags = USB_8DEV_STATUS_FRAME;
246 __be32 beflags;
247 __be16 bebrp;
248
249 memset(&outmsg, 0, sizeof(outmsg));
250 outmsg.command = USB_8DEV_OPEN;
251 outmsg.opt1 = USB_8DEV_BAUD_MANUAL;
252 outmsg.data[0] = bt->prop_seg + bt->phase_seg1;
253 outmsg.data[1] = bt->phase_seg2;
254 outmsg.data[2] = bt->sjw;
255
256 /* BRP */
257 bebrp = cpu_to_be16((u16)bt->brp);
258 memcpy(&outmsg.data[3], &bebrp, sizeof(bebrp));
259
260 /* flags */
261 if (ctrlmode & CAN_CTRLMODE_LOOPBACK)
262 flags |= USB_8DEV_LOOPBACK;
263 if (ctrlmode & CAN_CTRLMODE_LISTENONLY)
264 flags |= USB_8DEV_SILENT;
265 if (ctrlmode & CAN_CTRLMODE_ONE_SHOT)
266 flags |= USB_8DEV_DISABLE_AUTO_RESTRANS;
267
268 beflags = cpu_to_be32(flags);
269 memcpy(&outmsg.data[5], &beflags, sizeof(beflags));
270
271 return usb_8dev_send_cmd(priv, &outmsg, &inmsg);
272}
273
274/* Send close command to device */
275static int usb_8dev_cmd_close(struct usb_8dev_priv *priv)
276{
277 struct usb_8dev_cmd_msg inmsg;
278 struct usb_8dev_cmd_msg outmsg = {
279 .channel = 0,
280 .command = USB_8DEV_CLOSE,
281 .opt1 = 0,
282 .opt2 = 0
283 };
284
285 return usb_8dev_send_cmd(priv, &outmsg, &inmsg);
286}
287
288/* Get firmware and hardware version */
289static int usb_8dev_cmd_version(struct usb_8dev_priv *priv, u32 *res)
290{
291 struct usb_8dev_cmd_msg inmsg;
292 struct usb_8dev_cmd_msg outmsg = {
293 .channel = 0,
294 .command = USB_8DEV_GET_SOFTW_HARDW_VER,
295 .opt1 = 0,
296 .opt2 = 0
297 };
298
299 int err = usb_8dev_send_cmd(priv, &outmsg, &inmsg);
300 if (err)
301 return err;
302
303 *res = be32_to_cpup((__be32 *)inmsg.data);
304
305 return err;
306}
307
308/* Set network device mode
309 *
310 * Maybe we should leave this function empty, because the device
311 * set mode variable with open command.
312 */
313static int usb_8dev_set_mode(struct net_device *netdev, enum can_mode mode)
314{
315 struct usb_8dev_priv *priv = netdev_priv(netdev);
316 int err = 0;
317
318 switch (mode) {
319 case CAN_MODE_START:
320 err = usb_8dev_cmd_open(priv);
321 if (err)
322 netdev_warn(netdev, "couldn't start device");
323 break;
324
325 default:
326 return -EOPNOTSUPP;
327 }
328
329 return err;
330}
331
332/* Read error/status frames */
333static void usb_8dev_rx_err_msg(struct usb_8dev_priv *priv,
334 struct usb_8dev_rx_msg *msg)
335{
336 struct can_frame *cf;
337 struct sk_buff *skb;
338 struct net_device_stats *stats = &priv->netdev->stats;
339
340 /* Error message:
341 * byte 0: Status
342 * byte 1: bit 7: Receive Passive
343 * byte 1: bit 0-6: Receive Error Counter
344 * byte 2: Transmit Error Counter
345 * byte 3: Always 0 (maybe reserved for future use)
346 */
347
348 u8 state = msg->data[0];
349 u8 rxerr = msg->data[1] & USB_8DEV_RP_MASK;
350 u8 txerr = msg->data[2];
351 int rx_errors = 0;
352 int tx_errors = 0;
353
354 skb = alloc_can_err_skb(priv->netdev, &cf);
355 if (!skb)
356 return;
357
358 switch (state) {
359 case USB_8DEV_STATUSMSG_OK:
360 priv->can.state = CAN_STATE_ERROR_ACTIVE;
361 cf->can_id |= CAN_ERR_PROT;
362 cf->data[2] = CAN_ERR_PROT_ACTIVE;
363 break;
364 case USB_8DEV_STATUSMSG_BUSOFF:
365 priv->can.state = CAN_STATE_BUS_OFF;
366 cf->can_id |= CAN_ERR_BUSOFF;
367 priv->can.can_stats.bus_off++;
368 can_bus_off(priv->netdev);
369 break;
370 case USB_8DEV_STATUSMSG_OVERRUN:
371 case USB_8DEV_STATUSMSG_BUSLIGHT:
372 case USB_8DEV_STATUSMSG_BUSHEAVY:
373 cf->can_id |= CAN_ERR_CRTL;
374 break;
375 default:
376 priv->can.state = CAN_STATE_ERROR_WARNING;
377 cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
378 priv->can.can_stats.bus_error++;
379 break;
380 }
381
382 switch (state) {
383 case USB_8DEV_STATUSMSG_OK:
384 case USB_8DEV_STATUSMSG_BUSOFF:
385 break;
386 case USB_8DEV_STATUSMSG_ACK:
387 cf->can_id |= CAN_ERR_ACK;
388 tx_errors = 1;
389 break;
390 case USB_8DEV_STATUSMSG_CRC:
391 cf->data[3] = CAN_ERR_PROT_LOC_CRC_SEQ;
392 rx_errors = 1;
393 break;
394 case USB_8DEV_STATUSMSG_BIT0:
395 cf->data[2] |= CAN_ERR_PROT_BIT0;
396 tx_errors = 1;
397 break;
398 case USB_8DEV_STATUSMSG_BIT1:
399 cf->data[2] |= CAN_ERR_PROT_BIT1;
400 tx_errors = 1;
401 break;
402 case USB_8DEV_STATUSMSG_FORM:
403 cf->data[2] |= CAN_ERR_PROT_FORM;
404 rx_errors = 1;
405 break;
406 case USB_8DEV_STATUSMSG_STUFF:
407 cf->data[2] |= CAN_ERR_PROT_STUFF;
408 rx_errors = 1;
409 break;
410 case USB_8DEV_STATUSMSG_OVERRUN:
411 cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
412 stats->rx_over_errors++;
413 rx_errors = 1;
414 break;
415 case USB_8DEV_STATUSMSG_BUSLIGHT:
416 priv->can.state = CAN_STATE_ERROR_WARNING;
417 cf->data[1] = (txerr > rxerr) ?
418 CAN_ERR_CRTL_TX_WARNING :
419 CAN_ERR_CRTL_RX_WARNING;
420 priv->can.can_stats.error_warning++;
421 break;
422 case USB_8DEV_STATUSMSG_BUSHEAVY:
423 priv->can.state = CAN_STATE_ERROR_PASSIVE;
424 cf->data[1] = (txerr > rxerr) ?
425 CAN_ERR_CRTL_TX_PASSIVE :
426 CAN_ERR_CRTL_RX_PASSIVE;
427 priv->can.can_stats.error_passive++;
428 break;
429 default:
430 netdev_warn(priv->netdev,
431 "Unknown status/error message (%d)\n", state);
432 break;
433 }
434
435 if (tx_errors) {
436 cf->data[2] |= CAN_ERR_PROT_TX;
437 stats->tx_errors++;
438 }
439
440 if (rx_errors)
441 stats->rx_errors++;
442 if (priv->can.state != CAN_STATE_BUS_OFF) {
443 cf->can_id |= CAN_ERR_CNT;
444 cf->data[6] = txerr;
445 cf->data[7] = rxerr;
446 }
447
448 priv->bec.txerr = txerr;
449 priv->bec.rxerr = rxerr;
450
451 netif_rx(skb);
452}
453
454/* Read data and status frames */
455static void usb_8dev_rx_can_msg(struct usb_8dev_priv *priv,
456 struct usb_8dev_rx_msg *msg)
457{
458 struct can_frame *cf;
459 struct sk_buff *skb;
460 struct net_device_stats *stats = &priv->netdev->stats;
461
462 if (msg->type == USB_8DEV_TYPE_ERROR_FRAME &&
463 msg->flags == USB_8DEV_ERR_FLAG) {
464 usb_8dev_rx_err_msg(priv, msg);
465 } else if (msg->type == USB_8DEV_TYPE_CAN_FRAME) {
466 skb = alloc_can_skb(priv->netdev, &cf);
467 if (!skb)
468 return;
469
470 cf->can_id = be32_to_cpu(msg->id);
471 can_frame_set_cc_len(cf, msg->dlc & 0xF, priv->can.ctrlmode);
472
473 if (msg->flags & USB_8DEV_EXTID)
474 cf->can_id |= CAN_EFF_FLAG;
475
476 if (msg->flags & USB_8DEV_RTR) {
477 cf->can_id |= CAN_RTR_FLAG;
478 } else {
479 memcpy(cf->data, msg->data, cf->len);
480 stats->rx_bytes += cf->len;
481 }
482 stats->rx_packets++;
483
484 netif_rx(skb);
485 } else {
486 netdev_warn(priv->netdev, "frame type %d unknown",
487 msg->type);
488 }
489
490}
491
492/* Callback for reading data from device
493 *
494 * Check urb status, call read function and resubmit urb read operation.
495 */
496static void usb_8dev_read_bulk_callback(struct urb *urb)
497{
498 struct usb_8dev_priv *priv = urb->context;
499 struct net_device *netdev;
500 int retval;
501 int pos = 0;
502
503 netdev = priv->netdev;
504
505 if (!netif_device_present(netdev))
506 return;
507
508 switch (urb->status) {
509 case 0: /* success */
510 break;
511
512 case -ENOENT:
513 case -EPIPE:
514 case -EPROTO:
515 case -ESHUTDOWN:
516 return;
517
518 default:
519 netdev_info(netdev, "Rx URB aborted (%d)\n",
520 urb->status);
521 goto resubmit_urb;
522 }
523
524 while (pos < urb->actual_length) {
525 struct usb_8dev_rx_msg *msg;
526
527 if (pos + sizeof(struct usb_8dev_rx_msg) > urb->actual_length) {
528 netdev_err(priv->netdev, "format error\n");
529 break;
530 }
531
532 msg = (struct usb_8dev_rx_msg *)(urb->transfer_buffer + pos);
533 usb_8dev_rx_can_msg(priv, msg);
534
535 pos += sizeof(struct usb_8dev_rx_msg);
536 }
537
538resubmit_urb:
539 usb_fill_bulk_urb(urb, priv->udev,
540 usb_rcvbulkpipe(priv->udev, USB_8DEV_ENDP_DATA_RX),
541 urb->transfer_buffer, RX_BUFFER_SIZE,
542 usb_8dev_read_bulk_callback, priv);
543
544 retval = usb_submit_urb(urb, GFP_ATOMIC);
545
546 if (retval == -ENODEV)
547 netif_device_detach(netdev);
548 else if (retval)
549 netdev_err(netdev,
550 "failed resubmitting read bulk urb: %d\n", retval);
551}
552
553/* Callback handler for write operations
554 *
555 * Free allocated buffers, check transmit status and
556 * calculate statistic.
557 */
558static void usb_8dev_write_bulk_callback(struct urb *urb)
559{
560 struct usb_8dev_tx_urb_context *context = urb->context;
561 struct usb_8dev_priv *priv;
562 struct net_device *netdev;
563
564 BUG_ON(!context);
565
566 priv = context->priv;
567 netdev = priv->netdev;
568
569 /* free up our allocated buffer */
570 usb_free_coherent(urb->dev, urb->transfer_buffer_length,
571 urb->transfer_buffer, urb->transfer_dma);
572
573 atomic_dec(&priv->active_tx_urbs);
574
575 if (!netif_device_present(netdev))
576 return;
577
578 if (urb->status)
579 netdev_info(netdev, "Tx URB aborted (%d)\n",
580 urb->status);
581
582 netdev->stats.tx_packets++;
583 netdev->stats.tx_bytes += can_get_echo_skb(netdev, context->echo_index, NULL);
584
585 /* Release context */
586 context->echo_index = MAX_TX_URBS;
587
588 netif_wake_queue(netdev);
589}
590
591/* Send data to device */
592static netdev_tx_t usb_8dev_start_xmit(struct sk_buff *skb,
593 struct net_device *netdev)
594{
595 struct usb_8dev_priv *priv = netdev_priv(netdev);
596 struct net_device_stats *stats = &netdev->stats;
597 struct can_frame *cf = (struct can_frame *) skb->data;
598 struct usb_8dev_tx_msg *msg;
599 struct urb *urb;
600 struct usb_8dev_tx_urb_context *context = NULL;
601 u8 *buf;
602 int i, err;
603 size_t size = sizeof(struct usb_8dev_tx_msg);
604
605 if (can_dev_dropped_skb(netdev, skb))
606 return NETDEV_TX_OK;
607
608 /* create a URB, and a buffer for it, and copy the data to the URB */
609 urb = usb_alloc_urb(0, GFP_ATOMIC);
610 if (!urb)
611 goto nomem;
612
613 buf = usb_alloc_coherent(priv->udev, size, GFP_ATOMIC,
614 &urb->transfer_dma);
615 if (!buf) {
616 netdev_err(netdev, "No memory left for USB buffer\n");
617 goto nomembuf;
618 }
619
620 memset(buf, 0, size);
621
622 msg = (struct usb_8dev_tx_msg *)buf;
623 msg->begin = USB_8DEV_DATA_START;
624 msg->flags = 0x00;
625
626 if (cf->can_id & CAN_RTR_FLAG)
627 msg->flags |= USB_8DEV_RTR;
628
629 if (cf->can_id & CAN_EFF_FLAG)
630 msg->flags |= USB_8DEV_EXTID;
631
632 msg->id = cpu_to_be32(cf->can_id & CAN_ERR_MASK);
633 msg->dlc = can_get_cc_dlc(cf, priv->can.ctrlmode);
634 memcpy(msg->data, cf->data, cf->len);
635 msg->end = USB_8DEV_DATA_END;
636
637 for (i = 0; i < MAX_TX_URBS; i++) {
638 if (priv->tx_contexts[i].echo_index == MAX_TX_URBS) {
639 context = &priv->tx_contexts[i];
640 break;
641 }
642 }
643
644 /* May never happen! When this happens we'd more URBs in flight as
645 * allowed (MAX_TX_URBS).
646 */
647 if (!context)
648 goto nofreecontext;
649
650 context->priv = priv;
651 context->echo_index = i;
652
653 usb_fill_bulk_urb(urb, priv->udev,
654 usb_sndbulkpipe(priv->udev, USB_8DEV_ENDP_DATA_TX),
655 buf, size, usb_8dev_write_bulk_callback, context);
656 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
657 usb_anchor_urb(urb, &priv->tx_submitted);
658
659 can_put_echo_skb(skb, netdev, context->echo_index, 0);
660
661 atomic_inc(&priv->active_tx_urbs);
662
663 err = usb_submit_urb(urb, GFP_ATOMIC);
664 if (unlikely(err)) {
665 can_free_echo_skb(netdev, context->echo_index, NULL);
666
667 usb_unanchor_urb(urb);
668 usb_free_coherent(priv->udev, size, buf, urb->transfer_dma);
669
670 atomic_dec(&priv->active_tx_urbs);
671
672 if (err == -ENODEV)
673 netif_device_detach(netdev);
674 else
675 netdev_warn(netdev, "failed tx_urb %d\n", err);
676 stats->tx_dropped++;
677 } else if (atomic_read(&priv->active_tx_urbs) >= MAX_TX_URBS)
678 /* Slow down tx path */
679 netif_stop_queue(netdev);
680
681 /* Release our reference to this URB, the USB core will eventually free
682 * it entirely.
683 */
684 usb_free_urb(urb);
685
686 return NETDEV_TX_OK;
687
688nofreecontext:
689 usb_free_coherent(priv->udev, size, buf, urb->transfer_dma);
690 usb_free_urb(urb);
691
692 netdev_warn(netdev, "couldn't find free context");
693
694 return NETDEV_TX_BUSY;
695
696nomembuf:
697 usb_free_urb(urb);
698
699nomem:
700 dev_kfree_skb(skb);
701 stats->tx_dropped++;
702
703 return NETDEV_TX_OK;
704}
705
706static int usb_8dev_get_berr_counter(const struct net_device *netdev,
707 struct can_berr_counter *bec)
708{
709 struct usb_8dev_priv *priv = netdev_priv(netdev);
710
711 bec->txerr = priv->bec.txerr;
712 bec->rxerr = priv->bec.rxerr;
713
714 return 0;
715}
716
717/* Start USB device */
718static int usb_8dev_start(struct usb_8dev_priv *priv)
719{
720 struct net_device *netdev = priv->netdev;
721 int err, i;
722
723 for (i = 0; i < MAX_RX_URBS; i++) {
724 struct urb *urb = NULL;
725 u8 *buf;
726 dma_addr_t buf_dma;
727
728 /* create a URB, and a buffer for it */
729 urb = usb_alloc_urb(0, GFP_KERNEL);
730 if (!urb) {
731 err = -ENOMEM;
732 break;
733 }
734
735 buf = usb_alloc_coherent(priv->udev, RX_BUFFER_SIZE, GFP_KERNEL,
736 &buf_dma);
737 if (!buf) {
738 netdev_err(netdev, "No memory left for USB buffer\n");
739 usb_free_urb(urb);
740 err = -ENOMEM;
741 break;
742 }
743
744 urb->transfer_dma = buf_dma;
745
746 usb_fill_bulk_urb(urb, priv->udev,
747 usb_rcvbulkpipe(priv->udev,
748 USB_8DEV_ENDP_DATA_RX),
749 buf, RX_BUFFER_SIZE,
750 usb_8dev_read_bulk_callback, priv);
751 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
752 usb_anchor_urb(urb, &priv->rx_submitted);
753
754 err = usb_submit_urb(urb, GFP_KERNEL);
755 if (err) {
756 usb_unanchor_urb(urb);
757 usb_free_coherent(priv->udev, RX_BUFFER_SIZE, buf,
758 urb->transfer_dma);
759 usb_free_urb(urb);
760 break;
761 }
762
763 priv->rxbuf[i] = buf;
764 priv->rxbuf_dma[i] = buf_dma;
765
766 /* Drop reference, USB core will take care of freeing it */
767 usb_free_urb(urb);
768 }
769
770 /* Did we submit any URBs */
771 if (i == 0) {
772 netdev_warn(netdev, "couldn't setup read URBs\n");
773 return err;
774 }
775
776 /* Warn if we've couldn't transmit all the URBs */
777 if (i < MAX_RX_URBS)
778 netdev_warn(netdev, "rx performance may be slow\n");
779
780 err = usb_8dev_cmd_open(priv);
781 if (err)
782 goto failed;
783
784 priv->can.state = CAN_STATE_ERROR_ACTIVE;
785
786 return 0;
787
788failed:
789 if (err == -ENODEV)
790 netif_device_detach(priv->netdev);
791
792 netdev_warn(netdev, "couldn't submit control: %d\n", err);
793
794 return err;
795}
796
797/* Open USB device */
798static int usb_8dev_open(struct net_device *netdev)
799{
800 struct usb_8dev_priv *priv = netdev_priv(netdev);
801 int err;
802
803 /* common open */
804 err = open_candev(netdev);
805 if (err)
806 return err;
807
808 /* finally start device */
809 err = usb_8dev_start(priv);
810 if (err) {
811 if (err == -ENODEV)
812 netif_device_detach(priv->netdev);
813
814 netdev_warn(netdev, "couldn't start device: %d\n",
815 err);
816
817 close_candev(netdev);
818
819 return err;
820 }
821
822 netif_start_queue(netdev);
823
824 return 0;
825}
826
827static void unlink_all_urbs(struct usb_8dev_priv *priv)
828{
829 int i;
830
831 usb_kill_anchored_urbs(&priv->rx_submitted);
832
833 for (i = 0; i < MAX_RX_URBS; ++i)
834 usb_free_coherent(priv->udev, RX_BUFFER_SIZE,
835 priv->rxbuf[i], priv->rxbuf_dma[i]);
836
837 usb_kill_anchored_urbs(&priv->tx_submitted);
838 atomic_set(&priv->active_tx_urbs, 0);
839
840 for (i = 0; i < MAX_TX_URBS; i++)
841 priv->tx_contexts[i].echo_index = MAX_TX_URBS;
842}
843
844/* Close USB device */
845static int usb_8dev_close(struct net_device *netdev)
846{
847 struct usb_8dev_priv *priv = netdev_priv(netdev);
848 int err = 0;
849
850 /* Send CLOSE command to CAN controller */
851 err = usb_8dev_cmd_close(priv);
852 if (err)
853 netdev_warn(netdev, "couldn't stop device");
854
855 priv->can.state = CAN_STATE_STOPPED;
856
857 netif_stop_queue(netdev);
858
859 /* Stop polling */
860 unlink_all_urbs(priv);
861
862 close_candev(netdev);
863
864 return err;
865}
866
867static const struct net_device_ops usb_8dev_netdev_ops = {
868 .ndo_open = usb_8dev_open,
869 .ndo_stop = usb_8dev_close,
870 .ndo_start_xmit = usb_8dev_start_xmit,
871 .ndo_change_mtu = can_change_mtu,
872};
873
874static const struct ethtool_ops usb_8dev_ethtool_ops = {
875 .get_ts_info = ethtool_op_get_ts_info,
876};
877
878static const struct can_bittiming_const usb_8dev_bittiming_const = {
879 .name = KBUILD_MODNAME,
880 .tseg1_min = 1,
881 .tseg1_max = 16,
882 .tseg2_min = 1,
883 .tseg2_max = 8,
884 .sjw_max = 4,
885 .brp_min = 1,
886 .brp_max = 1024,
887 .brp_inc = 1,
888};
889
890/* Probe USB device
891 *
892 * Check device and firmware.
893 * Set supported modes and bittiming constants.
894 * Allocate some memory.
895 */
896static int usb_8dev_probe(struct usb_interface *intf,
897 const struct usb_device_id *id)
898{
899 struct net_device *netdev;
900 struct usb_8dev_priv *priv;
901 int i, err = -ENOMEM;
902 u32 version;
903 char buf[18];
904 struct usb_device *usbdev = interface_to_usbdev(intf);
905
906 /* product id looks strange, better we also check iProduct string */
907 if (usb_string(usbdev, usbdev->descriptor.iProduct, buf,
908 sizeof(buf)) > 0 && strcmp(buf, "USB2CAN converter")) {
909 dev_info(&usbdev->dev, "ignoring: not an USB2CAN converter\n");
910 return -ENODEV;
911 }
912
913 netdev = alloc_candev(sizeof(struct usb_8dev_priv), MAX_TX_URBS);
914 if (!netdev) {
915 dev_err(&intf->dev, "Couldn't alloc candev\n");
916 return -ENOMEM;
917 }
918
919 priv = netdev_priv(netdev);
920
921 priv->udev = usbdev;
922 priv->netdev = netdev;
923
924 priv->can.state = CAN_STATE_STOPPED;
925 priv->can.clock.freq = USB_8DEV_ABP_CLOCK;
926 priv->can.bittiming_const = &usb_8dev_bittiming_const;
927 priv->can.do_set_mode = usb_8dev_set_mode;
928 priv->can.do_get_berr_counter = usb_8dev_get_berr_counter;
929 priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK |
930 CAN_CTRLMODE_LISTENONLY |
931 CAN_CTRLMODE_ONE_SHOT |
932 CAN_CTRLMODE_CC_LEN8_DLC;
933
934 netdev->netdev_ops = &usb_8dev_netdev_ops;
935 netdev->ethtool_ops = &usb_8dev_ethtool_ops;
936
937 netdev->flags |= IFF_ECHO; /* we support local echo */
938
939 init_usb_anchor(&priv->rx_submitted);
940
941 init_usb_anchor(&priv->tx_submitted);
942 atomic_set(&priv->active_tx_urbs, 0);
943
944 for (i = 0; i < MAX_TX_URBS; i++)
945 priv->tx_contexts[i].echo_index = MAX_TX_URBS;
946
947 priv->cmd_msg_buffer = devm_kzalloc(&intf->dev, sizeof(struct usb_8dev_cmd_msg),
948 GFP_KERNEL);
949 if (!priv->cmd_msg_buffer)
950 goto cleanup_candev;
951
952 usb_set_intfdata(intf, priv);
953
954 SET_NETDEV_DEV(netdev, &intf->dev);
955
956 mutex_init(&priv->usb_8dev_cmd_lock);
957
958 err = register_candev(netdev);
959 if (err) {
960 netdev_err(netdev,
961 "couldn't register CAN device: %d\n", err);
962 goto cleanup_candev;
963 }
964
965 err = usb_8dev_cmd_version(priv, &version);
966 if (err) {
967 netdev_err(netdev, "can't get firmware version\n");
968 goto cleanup_unregister_candev;
969 } else {
970 netdev_info(netdev,
971 "firmware: %d.%d, hardware: %d.%d\n",
972 (version>>24) & 0xff, (version>>16) & 0xff,
973 (version>>8) & 0xff, version & 0xff);
974 }
975
976 return 0;
977
978cleanup_unregister_candev:
979 unregister_netdev(priv->netdev);
980
981cleanup_candev:
982 free_candev(netdev);
983
984 return err;
985
986}
987
988/* Called by the usb core when driver is unloaded or device is removed */
989static void usb_8dev_disconnect(struct usb_interface *intf)
990{
991 struct usb_8dev_priv *priv = usb_get_intfdata(intf);
992
993 usb_set_intfdata(intf, NULL);
994
995 if (priv) {
996 netdev_info(priv->netdev, "device disconnected\n");
997
998 unregister_netdev(priv->netdev);
999 unlink_all_urbs(priv);
1000 free_candev(priv->netdev);
1001 }
1002
1003}
1004
1005static struct usb_driver usb_8dev_driver = {
1006 .name = KBUILD_MODNAME,
1007 .probe = usb_8dev_probe,
1008 .disconnect = usb_8dev_disconnect,
1009 .id_table = usb_8dev_table,
1010};
1011
1012module_usb_driver(usb_8dev_driver);
1013
1014MODULE_AUTHOR("Bernd Krumboeck <krumboeck@universalnet.at>");
1015MODULE_DESCRIPTION("CAN driver for 8 devices USB2CAN interfaces");
1016MODULE_LICENSE("GPL v2");
1/*
2 * CAN driver for "8 devices" USB2CAN converter
3 *
4 * Copyright (C) 2012 Bernd Krumboeck (krumboeck@universalnet.at)
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License as published
8 * by the Free Software Foundation; version 2 of the License.
9 *
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License along
16 * with this program.
17 *
18 * This driver is inspired by the 3.2.0 version of drivers/net/can/usb/ems_usb.c
19 * and drivers/net/can/usb/esd_usb2.c
20 *
21 * Many thanks to Gerhard Bertelsmann (info@gerhard-bertelsmann.de)
22 * for testing and fixing this driver. Also many thanks to "8 devices",
23 * who were very cooperative and answered my questions.
24 */
25
26#include <linux/signal.h>
27#include <linux/slab.h>
28#include <linux/module.h>
29#include <linux/netdevice.h>
30#include <linux/usb.h>
31
32#include <linux/can.h>
33#include <linux/can/dev.h>
34#include <linux/can/error.h>
35#include <linux/can/led.h>
36
37/* driver constants */
38#define MAX_RX_URBS 20
39#define MAX_TX_URBS 20
40#define RX_BUFFER_SIZE 64
41
42/* vendor and product id */
43#define USB_8DEV_VENDOR_ID 0x0483
44#define USB_8DEV_PRODUCT_ID 0x1234
45
46/* endpoints */
47enum usb_8dev_endpoint {
48 USB_8DEV_ENDP_DATA_RX = 1,
49 USB_8DEV_ENDP_DATA_TX,
50 USB_8DEV_ENDP_CMD_RX,
51 USB_8DEV_ENDP_CMD_TX
52};
53
54/* device CAN clock */
55#define USB_8DEV_ABP_CLOCK 32000000
56
57/* setup flags */
58#define USB_8DEV_SILENT 0x01
59#define USB_8DEV_LOOPBACK 0x02
60#define USB_8DEV_DISABLE_AUTO_RESTRANS 0x04
61#define USB_8DEV_STATUS_FRAME 0x08
62
63/* commands */
64enum usb_8dev_cmd {
65 USB_8DEV_RESET = 1,
66 USB_8DEV_OPEN,
67 USB_8DEV_CLOSE,
68 USB_8DEV_SET_SPEED,
69 USB_8DEV_SET_MASK_FILTER,
70 USB_8DEV_GET_STATUS,
71 USB_8DEV_GET_STATISTICS,
72 USB_8DEV_GET_SERIAL,
73 USB_8DEV_GET_SOFTW_VER,
74 USB_8DEV_GET_HARDW_VER,
75 USB_8DEV_RESET_TIMESTAMP,
76 USB_8DEV_GET_SOFTW_HARDW_VER
77};
78
79/* command options */
80#define USB_8DEV_BAUD_MANUAL 0x09
81#define USB_8DEV_CMD_START 0x11
82#define USB_8DEV_CMD_END 0x22
83
84#define USB_8DEV_CMD_SUCCESS 0
85#define USB_8DEV_CMD_ERROR 255
86
87#define USB_8DEV_CMD_TIMEOUT 1000
88
89/* frames */
90#define USB_8DEV_DATA_START 0x55
91#define USB_8DEV_DATA_END 0xAA
92
93#define USB_8DEV_TYPE_CAN_FRAME 0
94#define USB_8DEV_TYPE_ERROR_FRAME 3
95
96#define USB_8DEV_EXTID 0x01
97#define USB_8DEV_RTR 0x02
98#define USB_8DEV_ERR_FLAG 0x04
99
100/* status */
101#define USB_8DEV_STATUSMSG_OK 0x00 /* Normal condition. */
102#define USB_8DEV_STATUSMSG_OVERRUN 0x01 /* Overrun occured when sending */
103#define USB_8DEV_STATUSMSG_BUSLIGHT 0x02 /* Error counter has reached 96 */
104#define USB_8DEV_STATUSMSG_BUSHEAVY 0x03 /* Error count. has reached 128 */
105#define USB_8DEV_STATUSMSG_BUSOFF 0x04 /* Device is in BUSOFF */
106#define USB_8DEV_STATUSMSG_STUFF 0x20 /* Stuff Error */
107#define USB_8DEV_STATUSMSG_FORM 0x21 /* Form Error */
108#define USB_8DEV_STATUSMSG_ACK 0x23 /* Ack Error */
109#define USB_8DEV_STATUSMSG_BIT0 0x24 /* Bit1 Error */
110#define USB_8DEV_STATUSMSG_BIT1 0x25 /* Bit0 Error */
111#define USB_8DEV_STATUSMSG_CRC 0x27 /* CRC Error */
112
113#define USB_8DEV_RP_MASK 0x7F /* Mask for Receive Error Bit */
114
115
116/* table of devices that work with this driver */
117static const struct usb_device_id usb_8dev_table[] = {
118 { USB_DEVICE(USB_8DEV_VENDOR_ID, USB_8DEV_PRODUCT_ID) },
119 { } /* Terminating entry */
120};
121
122MODULE_DEVICE_TABLE(usb, usb_8dev_table);
123
124struct usb_8dev_tx_urb_context {
125 struct usb_8dev_priv *priv;
126
127 u32 echo_index;
128 u8 dlc;
129};
130
131/* Structure to hold all of our device specific stuff */
132struct usb_8dev_priv {
133 struct can_priv can; /* must be the first member */
134
135 struct sk_buff *echo_skb[MAX_TX_URBS];
136
137 struct usb_device *udev;
138 struct net_device *netdev;
139
140 atomic_t active_tx_urbs;
141 struct usb_anchor tx_submitted;
142 struct usb_8dev_tx_urb_context tx_contexts[MAX_TX_URBS];
143
144 struct usb_anchor rx_submitted;
145
146 struct can_berr_counter bec;
147
148 u8 *cmd_msg_buffer;
149
150 struct mutex usb_8dev_cmd_lock;
151
152};
153
154/* tx frame */
155struct __packed usb_8dev_tx_msg {
156 u8 begin;
157 u8 flags; /* RTR and EXT_ID flag */
158 __be32 id; /* upper 3 bits not used */
159 u8 dlc; /* data length code 0-8 bytes */
160 u8 data[8]; /* 64-bit data */
161 u8 end;
162};
163
164/* rx frame */
165struct __packed usb_8dev_rx_msg {
166 u8 begin;
167 u8 type; /* frame type */
168 u8 flags; /* RTR and EXT_ID flag */
169 __be32 id; /* upper 3 bits not used */
170 u8 dlc; /* data length code 0-8 bytes */
171 u8 data[8]; /* 64-bit data */
172 __be32 timestamp; /* 32-bit timestamp */
173 u8 end;
174};
175
176/* command frame */
177struct __packed usb_8dev_cmd_msg {
178 u8 begin;
179 u8 channel; /* unkown - always 0 */
180 u8 command; /* command to execute */
181 u8 opt1; /* optional parameter / return value */
182 u8 opt2; /* optional parameter 2 */
183 u8 data[10]; /* optional parameter and data */
184 u8 end;
185};
186
187static int usb_8dev_send_cmd_msg(struct usb_8dev_priv *priv, u8 *msg, int size)
188{
189 int actual_length;
190
191 return usb_bulk_msg(priv->udev,
192 usb_sndbulkpipe(priv->udev, USB_8DEV_ENDP_CMD_TX),
193 msg, size, &actual_length, USB_8DEV_CMD_TIMEOUT);
194}
195
196static int usb_8dev_wait_cmd_msg(struct usb_8dev_priv *priv, u8 *msg, int size,
197 int *actual_length)
198{
199 return usb_bulk_msg(priv->udev,
200 usb_rcvbulkpipe(priv->udev, USB_8DEV_ENDP_CMD_RX),
201 msg, size, actual_length, USB_8DEV_CMD_TIMEOUT);
202}
203
204/* Send command to device and receive result.
205 * Command was successful when opt1 = 0.
206 */
207static int usb_8dev_send_cmd(struct usb_8dev_priv *priv,
208 struct usb_8dev_cmd_msg *out,
209 struct usb_8dev_cmd_msg *in)
210{
211 int err;
212 int num_bytes_read;
213 struct net_device *netdev;
214
215 netdev = priv->netdev;
216
217 out->begin = USB_8DEV_CMD_START;
218 out->end = USB_8DEV_CMD_END;
219
220 mutex_lock(&priv->usb_8dev_cmd_lock);
221
222 memcpy(priv->cmd_msg_buffer, out,
223 sizeof(struct usb_8dev_cmd_msg));
224
225 err = usb_8dev_send_cmd_msg(priv, priv->cmd_msg_buffer,
226 sizeof(struct usb_8dev_cmd_msg));
227 if (err < 0) {
228 netdev_err(netdev, "sending command message failed\n");
229 goto failed;
230 }
231
232 err = usb_8dev_wait_cmd_msg(priv, priv->cmd_msg_buffer,
233 sizeof(struct usb_8dev_cmd_msg),
234 &num_bytes_read);
235 if (err < 0) {
236 netdev_err(netdev, "no command message answer\n");
237 goto failed;
238 }
239
240 memcpy(in, priv->cmd_msg_buffer, sizeof(struct usb_8dev_cmd_msg));
241
242 if (in->begin != USB_8DEV_CMD_START || in->end != USB_8DEV_CMD_END ||
243 num_bytes_read != 16 || in->opt1 != 0)
244 err = -EPROTO;
245
246failed:
247 mutex_unlock(&priv->usb_8dev_cmd_lock);
248 return err;
249}
250
251/* Send open command to device */
252static int usb_8dev_cmd_open(struct usb_8dev_priv *priv)
253{
254 struct can_bittiming *bt = &priv->can.bittiming;
255 struct usb_8dev_cmd_msg outmsg;
256 struct usb_8dev_cmd_msg inmsg;
257 u32 ctrlmode = priv->can.ctrlmode;
258 u32 flags = USB_8DEV_STATUS_FRAME;
259 __be32 beflags;
260 __be16 bebrp;
261
262 memset(&outmsg, 0, sizeof(outmsg));
263 outmsg.command = USB_8DEV_OPEN;
264 outmsg.opt1 = USB_8DEV_BAUD_MANUAL;
265 outmsg.data[0] = bt->prop_seg + bt->phase_seg1;
266 outmsg.data[1] = bt->phase_seg2;
267 outmsg.data[2] = bt->sjw;
268
269 /* BRP */
270 bebrp = cpu_to_be16((u16)bt->brp);
271 memcpy(&outmsg.data[3], &bebrp, sizeof(bebrp));
272
273 /* flags */
274 if (ctrlmode & CAN_CTRLMODE_LOOPBACK)
275 flags |= USB_8DEV_LOOPBACK;
276 if (ctrlmode & CAN_CTRLMODE_LISTENONLY)
277 flags |= USB_8DEV_SILENT;
278 if (ctrlmode & CAN_CTRLMODE_ONE_SHOT)
279 flags |= USB_8DEV_DISABLE_AUTO_RESTRANS;
280
281 beflags = cpu_to_be32(flags);
282 memcpy(&outmsg.data[5], &beflags, sizeof(beflags));
283
284 return usb_8dev_send_cmd(priv, &outmsg, &inmsg);
285}
286
287/* Send close command to device */
288static int usb_8dev_cmd_close(struct usb_8dev_priv *priv)
289{
290 struct usb_8dev_cmd_msg inmsg;
291 struct usb_8dev_cmd_msg outmsg = {
292 .channel = 0,
293 .command = USB_8DEV_CLOSE,
294 .opt1 = 0,
295 .opt2 = 0
296 };
297
298 return usb_8dev_send_cmd(priv, &outmsg, &inmsg);
299}
300
301/* Get firmware and hardware version */
302static int usb_8dev_cmd_version(struct usb_8dev_priv *priv, u32 *res)
303{
304 struct usb_8dev_cmd_msg inmsg;
305 struct usb_8dev_cmd_msg outmsg = {
306 .channel = 0,
307 .command = USB_8DEV_GET_SOFTW_HARDW_VER,
308 .opt1 = 0,
309 .opt2 = 0
310 };
311
312 int err = usb_8dev_send_cmd(priv, &outmsg, &inmsg);
313 if (err)
314 return err;
315
316 *res = be32_to_cpup((__be32 *)inmsg.data);
317
318 return err;
319}
320
321/* Set network device mode
322 *
323 * Maybe we should leave this function empty, because the device
324 * set mode variable with open command.
325 */
326static int usb_8dev_set_mode(struct net_device *netdev, enum can_mode mode)
327{
328 struct usb_8dev_priv *priv = netdev_priv(netdev);
329 int err = 0;
330
331 switch (mode) {
332 case CAN_MODE_START:
333 err = usb_8dev_cmd_open(priv);
334 if (err)
335 netdev_warn(netdev, "couldn't start device");
336 break;
337
338 default:
339 return -EOPNOTSUPP;
340 }
341
342 return err;
343}
344
345/* Read error/status frames */
346static void usb_8dev_rx_err_msg(struct usb_8dev_priv *priv,
347 struct usb_8dev_rx_msg *msg)
348{
349 struct can_frame *cf;
350 struct sk_buff *skb;
351 struct net_device_stats *stats = &priv->netdev->stats;
352
353 /* Error message:
354 * byte 0: Status
355 * byte 1: bit 7: Receive Passive
356 * byte 1: bit 0-6: Receive Error Counter
357 * byte 2: Transmit Error Counter
358 * byte 3: Always 0 (maybe reserved for future use)
359 */
360
361 u8 state = msg->data[0];
362 u8 rxerr = msg->data[1] & USB_8DEV_RP_MASK;
363 u8 txerr = msg->data[2];
364 int rx_errors = 0;
365 int tx_errors = 0;
366
367 skb = alloc_can_err_skb(priv->netdev, &cf);
368 if (!skb)
369 return;
370
371 switch (state) {
372 case USB_8DEV_STATUSMSG_OK:
373 priv->can.state = CAN_STATE_ERROR_ACTIVE;
374 cf->can_id |= CAN_ERR_PROT;
375 cf->data[2] = CAN_ERR_PROT_ACTIVE;
376 break;
377 case USB_8DEV_STATUSMSG_BUSOFF:
378 priv->can.state = CAN_STATE_BUS_OFF;
379 cf->can_id |= CAN_ERR_BUSOFF;
380 can_bus_off(priv->netdev);
381 break;
382 case USB_8DEV_STATUSMSG_OVERRUN:
383 case USB_8DEV_STATUSMSG_BUSLIGHT:
384 case USB_8DEV_STATUSMSG_BUSHEAVY:
385 cf->can_id |= CAN_ERR_CRTL;
386 break;
387 default:
388 priv->can.state = CAN_STATE_ERROR_WARNING;
389 cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
390 priv->can.can_stats.bus_error++;
391 break;
392 }
393
394 switch (state) {
395 case USB_8DEV_STATUSMSG_OK:
396 case USB_8DEV_STATUSMSG_BUSOFF:
397 break;
398 case USB_8DEV_STATUSMSG_ACK:
399 cf->can_id |= CAN_ERR_ACK;
400 tx_errors = 1;
401 break;
402 case USB_8DEV_STATUSMSG_CRC:
403 cf->data[2] |= CAN_ERR_PROT_UNSPEC;
404 cf->data[3] |= CAN_ERR_PROT_LOC_CRC_SEQ |
405 CAN_ERR_PROT_LOC_CRC_DEL;
406 rx_errors = 1;
407 break;
408 case USB_8DEV_STATUSMSG_BIT0:
409 cf->data[2] |= CAN_ERR_PROT_BIT0;
410 tx_errors = 1;
411 break;
412 case USB_8DEV_STATUSMSG_BIT1:
413 cf->data[2] |= CAN_ERR_PROT_BIT1;
414 tx_errors = 1;
415 break;
416 case USB_8DEV_STATUSMSG_FORM:
417 cf->data[2] |= CAN_ERR_PROT_FORM;
418 rx_errors = 1;
419 break;
420 case USB_8DEV_STATUSMSG_STUFF:
421 cf->data[2] |= CAN_ERR_PROT_STUFF;
422 rx_errors = 1;
423 break;
424 case USB_8DEV_STATUSMSG_OVERRUN:
425 cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
426 stats->rx_over_errors++;
427 rx_errors = 1;
428 break;
429 case USB_8DEV_STATUSMSG_BUSLIGHT:
430 priv->can.state = CAN_STATE_ERROR_WARNING;
431 cf->data[1] = (txerr > rxerr) ?
432 CAN_ERR_CRTL_TX_WARNING :
433 CAN_ERR_CRTL_RX_WARNING;
434 priv->can.can_stats.error_warning++;
435 break;
436 case USB_8DEV_STATUSMSG_BUSHEAVY:
437 priv->can.state = CAN_STATE_ERROR_PASSIVE;
438 cf->data[1] = (txerr > rxerr) ?
439 CAN_ERR_CRTL_TX_PASSIVE :
440 CAN_ERR_CRTL_RX_PASSIVE;
441 priv->can.can_stats.error_passive++;
442 break;
443 default:
444 netdev_warn(priv->netdev,
445 "Unknown status/error message (%d)\n", state);
446 break;
447 }
448
449 if (tx_errors) {
450 cf->data[2] |= CAN_ERR_PROT_TX;
451 stats->tx_errors++;
452 }
453
454 if (rx_errors)
455 stats->rx_errors++;
456
457 cf->data[6] = txerr;
458 cf->data[7] = rxerr;
459
460 priv->bec.txerr = txerr;
461 priv->bec.rxerr = rxerr;
462
463 netif_rx(skb);
464
465 stats->rx_packets++;
466 stats->rx_bytes += cf->can_dlc;
467}
468
469/* Read data and status frames */
470static void usb_8dev_rx_can_msg(struct usb_8dev_priv *priv,
471 struct usb_8dev_rx_msg *msg)
472{
473 struct can_frame *cf;
474 struct sk_buff *skb;
475 struct net_device_stats *stats = &priv->netdev->stats;
476
477 if (msg->type == USB_8DEV_TYPE_ERROR_FRAME &&
478 msg->flags == USB_8DEV_ERR_FLAG) {
479 usb_8dev_rx_err_msg(priv, msg);
480 } else if (msg->type == USB_8DEV_TYPE_CAN_FRAME) {
481 skb = alloc_can_skb(priv->netdev, &cf);
482 if (!skb)
483 return;
484
485 cf->can_id = be32_to_cpu(msg->id);
486 cf->can_dlc = get_can_dlc(msg->dlc & 0xF);
487
488 if (msg->flags & USB_8DEV_EXTID)
489 cf->can_id |= CAN_EFF_FLAG;
490
491 if (msg->flags & USB_8DEV_RTR)
492 cf->can_id |= CAN_RTR_FLAG;
493 else
494 memcpy(cf->data, msg->data, cf->can_dlc);
495
496 netif_rx(skb);
497
498 stats->rx_packets++;
499 stats->rx_bytes += cf->can_dlc;
500
501 can_led_event(priv->netdev, CAN_LED_EVENT_RX);
502 } else {
503 netdev_warn(priv->netdev, "frame type %d unknown",
504 msg->type);
505 }
506
507}
508
509/* Callback for reading data from device
510 *
511 * Check urb status, call read function and resubmit urb read operation.
512 */
513static void usb_8dev_read_bulk_callback(struct urb *urb)
514{
515 struct usb_8dev_priv *priv = urb->context;
516 struct net_device *netdev;
517 int retval;
518 int pos = 0;
519
520 netdev = priv->netdev;
521
522 if (!netif_device_present(netdev))
523 return;
524
525 switch (urb->status) {
526 case 0: /* success */
527 break;
528
529 case -ENOENT:
530 case -ESHUTDOWN:
531 return;
532
533 default:
534 netdev_info(netdev, "Rx URB aborted (%d)\n",
535 urb->status);
536 goto resubmit_urb;
537 }
538
539 while (pos < urb->actual_length) {
540 struct usb_8dev_rx_msg *msg;
541
542 if (pos + sizeof(struct usb_8dev_rx_msg) > urb->actual_length) {
543 netdev_err(priv->netdev, "format error\n");
544 break;
545 }
546
547 msg = (struct usb_8dev_rx_msg *)(urb->transfer_buffer + pos);
548 usb_8dev_rx_can_msg(priv, msg);
549
550 pos += sizeof(struct usb_8dev_rx_msg);
551 }
552
553resubmit_urb:
554 usb_fill_bulk_urb(urb, priv->udev,
555 usb_rcvbulkpipe(priv->udev, USB_8DEV_ENDP_DATA_RX),
556 urb->transfer_buffer, RX_BUFFER_SIZE,
557 usb_8dev_read_bulk_callback, priv);
558
559 retval = usb_submit_urb(urb, GFP_ATOMIC);
560
561 if (retval == -ENODEV)
562 netif_device_detach(netdev);
563 else if (retval)
564 netdev_err(netdev,
565 "failed resubmitting read bulk urb: %d\n", retval);
566}
567
568/* Callback handler for write operations
569 *
570 * Free allocated buffers, check transmit status and
571 * calculate statistic.
572 */
573static void usb_8dev_write_bulk_callback(struct urb *urb)
574{
575 struct usb_8dev_tx_urb_context *context = urb->context;
576 struct usb_8dev_priv *priv;
577 struct net_device *netdev;
578
579 BUG_ON(!context);
580
581 priv = context->priv;
582 netdev = priv->netdev;
583
584 /* free up our allocated buffer */
585 usb_free_coherent(urb->dev, urb->transfer_buffer_length,
586 urb->transfer_buffer, urb->transfer_dma);
587
588 atomic_dec(&priv->active_tx_urbs);
589
590 if (!netif_device_present(netdev))
591 return;
592
593 if (urb->status)
594 netdev_info(netdev, "Tx URB aborted (%d)\n",
595 urb->status);
596
597 netdev->stats.tx_packets++;
598 netdev->stats.tx_bytes += context->dlc;
599
600 can_get_echo_skb(netdev, context->echo_index);
601
602 can_led_event(netdev, CAN_LED_EVENT_TX);
603
604 /* Release context */
605 context->echo_index = MAX_TX_URBS;
606
607 netif_wake_queue(netdev);
608}
609
610/* Send data to device */
611static netdev_tx_t usb_8dev_start_xmit(struct sk_buff *skb,
612 struct net_device *netdev)
613{
614 struct usb_8dev_priv *priv = netdev_priv(netdev);
615 struct net_device_stats *stats = &netdev->stats;
616 struct can_frame *cf = (struct can_frame *) skb->data;
617 struct usb_8dev_tx_msg *msg;
618 struct urb *urb;
619 struct usb_8dev_tx_urb_context *context = NULL;
620 u8 *buf;
621 int i, err;
622 size_t size = sizeof(struct usb_8dev_tx_msg);
623
624 if (can_dropped_invalid_skb(netdev, skb))
625 return NETDEV_TX_OK;
626
627 /* create a URB, and a buffer for it, and copy the data to the URB */
628 urb = usb_alloc_urb(0, GFP_ATOMIC);
629 if (!urb) {
630 netdev_err(netdev, "No memory left for URBs\n");
631 goto nomem;
632 }
633
634 buf = usb_alloc_coherent(priv->udev, size, GFP_ATOMIC,
635 &urb->transfer_dma);
636 if (!buf) {
637 netdev_err(netdev, "No memory left for USB buffer\n");
638 goto nomembuf;
639 }
640
641 memset(buf, 0, size);
642
643 msg = (struct usb_8dev_tx_msg *)buf;
644 msg->begin = USB_8DEV_DATA_START;
645 msg->flags = 0x00;
646
647 if (cf->can_id & CAN_RTR_FLAG)
648 msg->flags |= USB_8DEV_RTR;
649
650 if (cf->can_id & CAN_EFF_FLAG)
651 msg->flags |= USB_8DEV_EXTID;
652
653 msg->id = cpu_to_be32(cf->can_id & CAN_ERR_MASK);
654 msg->dlc = cf->can_dlc;
655 memcpy(msg->data, cf->data, cf->can_dlc);
656 msg->end = USB_8DEV_DATA_END;
657
658 for (i = 0; i < MAX_TX_URBS; i++) {
659 if (priv->tx_contexts[i].echo_index == MAX_TX_URBS) {
660 context = &priv->tx_contexts[i];
661 break;
662 }
663 }
664
665 /* May never happen! When this happens we'd more URBs in flight as
666 * allowed (MAX_TX_URBS).
667 */
668 if (!context)
669 goto nofreecontext;
670
671 context->priv = priv;
672 context->echo_index = i;
673 context->dlc = cf->can_dlc;
674
675 usb_fill_bulk_urb(urb, priv->udev,
676 usb_sndbulkpipe(priv->udev, USB_8DEV_ENDP_DATA_TX),
677 buf, size, usb_8dev_write_bulk_callback, context);
678 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
679 usb_anchor_urb(urb, &priv->tx_submitted);
680
681 can_put_echo_skb(skb, netdev, context->echo_index);
682
683 atomic_inc(&priv->active_tx_urbs);
684
685 err = usb_submit_urb(urb, GFP_ATOMIC);
686 if (unlikely(err))
687 goto failed;
688 else if (atomic_read(&priv->active_tx_urbs) >= MAX_TX_URBS)
689 /* Slow down tx path */
690 netif_stop_queue(netdev);
691
692 /* Release our reference to this URB, the USB core will eventually free
693 * it entirely.
694 */
695 usb_free_urb(urb);
696
697 return NETDEV_TX_OK;
698
699nofreecontext:
700 usb_free_coherent(priv->udev, size, buf, urb->transfer_dma);
701 usb_free_urb(urb);
702
703 netdev_warn(netdev, "couldn't find free context");
704
705 return NETDEV_TX_BUSY;
706
707failed:
708 can_free_echo_skb(netdev, context->echo_index);
709
710 usb_unanchor_urb(urb);
711 usb_free_coherent(priv->udev, size, buf, urb->transfer_dma);
712
713 atomic_dec(&priv->active_tx_urbs);
714
715 if (err == -ENODEV)
716 netif_device_detach(netdev);
717 else
718 netdev_warn(netdev, "failed tx_urb %d\n", err);
719
720nomembuf:
721 usb_free_urb(urb);
722
723nomem:
724 dev_kfree_skb(skb);
725 stats->tx_dropped++;
726
727 return NETDEV_TX_OK;
728}
729
730static int usb_8dev_get_berr_counter(const struct net_device *netdev,
731 struct can_berr_counter *bec)
732{
733 struct usb_8dev_priv *priv = netdev_priv(netdev);
734
735 bec->txerr = priv->bec.txerr;
736 bec->rxerr = priv->bec.rxerr;
737
738 return 0;
739}
740
741/* Start USB device */
742static int usb_8dev_start(struct usb_8dev_priv *priv)
743{
744 struct net_device *netdev = priv->netdev;
745 int err, i;
746
747 for (i = 0; i < MAX_RX_URBS; i++) {
748 struct urb *urb = NULL;
749 u8 *buf;
750
751 /* create a URB, and a buffer for it */
752 urb = usb_alloc_urb(0, GFP_KERNEL);
753 if (!urb) {
754 netdev_err(netdev, "No memory left for URBs\n");
755 err = -ENOMEM;
756 break;
757 }
758
759 buf = usb_alloc_coherent(priv->udev, RX_BUFFER_SIZE, GFP_KERNEL,
760 &urb->transfer_dma);
761 if (!buf) {
762 netdev_err(netdev, "No memory left for USB buffer\n");
763 usb_free_urb(urb);
764 err = -ENOMEM;
765 break;
766 }
767
768 usb_fill_bulk_urb(urb, priv->udev,
769 usb_rcvbulkpipe(priv->udev,
770 USB_8DEV_ENDP_DATA_RX),
771 buf, RX_BUFFER_SIZE,
772 usb_8dev_read_bulk_callback, priv);
773 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
774 usb_anchor_urb(urb, &priv->rx_submitted);
775
776 err = usb_submit_urb(urb, GFP_KERNEL);
777 if (err) {
778 usb_unanchor_urb(urb);
779 usb_free_coherent(priv->udev, RX_BUFFER_SIZE, buf,
780 urb->transfer_dma);
781 usb_free_urb(urb);
782 break;
783 }
784
785 /* Drop reference, USB core will take care of freeing it */
786 usb_free_urb(urb);
787 }
788
789 /* Did we submit any URBs */
790 if (i == 0) {
791 netdev_warn(netdev, "couldn't setup read URBs\n");
792 return err;
793 }
794
795 /* Warn if we've couldn't transmit all the URBs */
796 if (i < MAX_RX_URBS)
797 netdev_warn(netdev, "rx performance may be slow\n");
798
799 err = usb_8dev_cmd_open(priv);
800 if (err)
801 goto failed;
802
803 priv->can.state = CAN_STATE_ERROR_ACTIVE;
804
805 return 0;
806
807failed:
808 if (err == -ENODEV)
809 netif_device_detach(priv->netdev);
810
811 netdev_warn(netdev, "couldn't submit control: %d\n", err);
812
813 return err;
814}
815
816/* Open USB device */
817static int usb_8dev_open(struct net_device *netdev)
818{
819 struct usb_8dev_priv *priv = netdev_priv(netdev);
820 int err;
821
822 /* common open */
823 err = open_candev(netdev);
824 if (err)
825 return err;
826
827 can_led_event(netdev, CAN_LED_EVENT_OPEN);
828
829 /* finally start device */
830 err = usb_8dev_start(priv);
831 if (err) {
832 if (err == -ENODEV)
833 netif_device_detach(priv->netdev);
834
835 netdev_warn(netdev, "couldn't start device: %d\n",
836 err);
837
838 close_candev(netdev);
839
840 return err;
841 }
842
843 netif_start_queue(netdev);
844
845 return 0;
846}
847
848static void unlink_all_urbs(struct usb_8dev_priv *priv)
849{
850 int i;
851
852 usb_kill_anchored_urbs(&priv->rx_submitted);
853
854 usb_kill_anchored_urbs(&priv->tx_submitted);
855 atomic_set(&priv->active_tx_urbs, 0);
856
857 for (i = 0; i < MAX_TX_URBS; i++)
858 priv->tx_contexts[i].echo_index = MAX_TX_URBS;
859}
860
861/* Close USB device */
862static int usb_8dev_close(struct net_device *netdev)
863{
864 struct usb_8dev_priv *priv = netdev_priv(netdev);
865 int err = 0;
866
867 /* Send CLOSE command to CAN controller */
868 err = usb_8dev_cmd_close(priv);
869 if (err)
870 netdev_warn(netdev, "couldn't stop device");
871
872 priv->can.state = CAN_STATE_STOPPED;
873
874 netif_stop_queue(netdev);
875
876 /* Stop polling */
877 unlink_all_urbs(priv);
878
879 close_candev(netdev);
880
881 can_led_event(netdev, CAN_LED_EVENT_STOP);
882
883 return err;
884}
885
886static const struct net_device_ops usb_8dev_netdev_ops = {
887 .ndo_open = usb_8dev_open,
888 .ndo_stop = usb_8dev_close,
889 .ndo_start_xmit = usb_8dev_start_xmit,
890 .ndo_change_mtu = can_change_mtu,
891};
892
893static const struct can_bittiming_const usb_8dev_bittiming_const = {
894 .name = "usb_8dev",
895 .tseg1_min = 1,
896 .tseg1_max = 16,
897 .tseg2_min = 1,
898 .tseg2_max = 8,
899 .sjw_max = 4,
900 .brp_min = 1,
901 .brp_max = 1024,
902 .brp_inc = 1,
903};
904
905/* Probe USB device
906 *
907 * Check device and firmware.
908 * Set supported modes and bittiming constants.
909 * Allocate some memory.
910 */
911static int usb_8dev_probe(struct usb_interface *intf,
912 const struct usb_device_id *id)
913{
914 struct net_device *netdev;
915 struct usb_8dev_priv *priv;
916 int i, err = -ENOMEM;
917 u32 version;
918 char buf[18];
919 struct usb_device *usbdev = interface_to_usbdev(intf);
920
921 /* product id looks strange, better we also check iProduct string */
922 if (usb_string(usbdev, usbdev->descriptor.iProduct, buf,
923 sizeof(buf)) > 0 && strcmp(buf, "USB2CAN converter")) {
924 dev_info(&usbdev->dev, "ignoring: not an USB2CAN converter\n");
925 return -ENODEV;
926 }
927
928 netdev = alloc_candev(sizeof(struct usb_8dev_priv), MAX_TX_URBS);
929 if (!netdev) {
930 dev_err(&intf->dev, "Couldn't alloc candev\n");
931 return -ENOMEM;
932 }
933
934 priv = netdev_priv(netdev);
935
936 priv->udev = usbdev;
937 priv->netdev = netdev;
938
939 priv->can.state = CAN_STATE_STOPPED;
940 priv->can.clock.freq = USB_8DEV_ABP_CLOCK;
941 priv->can.bittiming_const = &usb_8dev_bittiming_const;
942 priv->can.do_set_mode = usb_8dev_set_mode;
943 priv->can.do_get_berr_counter = usb_8dev_get_berr_counter;
944 priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK |
945 CAN_CTRLMODE_LISTENONLY |
946 CAN_CTRLMODE_ONE_SHOT;
947
948 netdev->netdev_ops = &usb_8dev_netdev_ops;
949
950 netdev->flags |= IFF_ECHO; /* we support local echo */
951
952 init_usb_anchor(&priv->rx_submitted);
953
954 init_usb_anchor(&priv->tx_submitted);
955 atomic_set(&priv->active_tx_urbs, 0);
956
957 for (i = 0; i < MAX_TX_URBS; i++)
958 priv->tx_contexts[i].echo_index = MAX_TX_URBS;
959
960 priv->cmd_msg_buffer = kzalloc(sizeof(struct usb_8dev_cmd_msg),
961 GFP_KERNEL);
962 if (!priv->cmd_msg_buffer)
963 goto cleanup_candev;
964
965 usb_set_intfdata(intf, priv);
966
967 SET_NETDEV_DEV(netdev, &intf->dev);
968
969 mutex_init(&priv->usb_8dev_cmd_lock);
970
971 err = register_candev(netdev);
972 if (err) {
973 netdev_err(netdev,
974 "couldn't register CAN device: %d\n", err);
975 goto cleanup_cmd_msg_buffer;
976 }
977
978 err = usb_8dev_cmd_version(priv, &version);
979 if (err) {
980 netdev_err(netdev, "can't get firmware version\n");
981 goto cleanup_unregister_candev;
982 } else {
983 netdev_info(netdev,
984 "firmware: %d.%d, hardware: %d.%d\n",
985 (version>>24) & 0xff, (version>>16) & 0xff,
986 (version>>8) & 0xff, version & 0xff);
987 }
988
989 devm_can_led_init(netdev);
990
991 return 0;
992
993cleanup_unregister_candev:
994 unregister_netdev(priv->netdev);
995
996cleanup_cmd_msg_buffer:
997 kfree(priv->cmd_msg_buffer);
998
999cleanup_candev:
1000 free_candev(netdev);
1001
1002 return err;
1003
1004}
1005
1006/* Called by the usb core when driver is unloaded or device is removed */
1007static void usb_8dev_disconnect(struct usb_interface *intf)
1008{
1009 struct usb_8dev_priv *priv = usb_get_intfdata(intf);
1010
1011 usb_set_intfdata(intf, NULL);
1012
1013 if (priv) {
1014 netdev_info(priv->netdev, "device disconnected\n");
1015
1016 unregister_netdev(priv->netdev);
1017 free_candev(priv->netdev);
1018
1019 unlink_all_urbs(priv);
1020 }
1021
1022}
1023
1024static struct usb_driver usb_8dev_driver = {
1025 .name = "usb_8dev",
1026 .probe = usb_8dev_probe,
1027 .disconnect = usb_8dev_disconnect,
1028 .id_table = usb_8dev_table,
1029};
1030
1031module_usb_driver(usb_8dev_driver);
1032
1033MODULE_AUTHOR("Bernd Krumboeck <krumboeck@universalnet.at>");
1034MODULE_DESCRIPTION("CAN driver for 8 devices USB2CAN interfaces");
1035MODULE_LICENSE("GPL v2");