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[deliverable/linux.git] / drivers / net / can / usb / usb_8dev.c
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/init.h>
27 #include <linux/signal.h>
28 #include <linux/slab.h>
29 #include <linux/module.h>
30 #include <linux/netdevice.h>
31 #include <linux/usb.h>
32
33 #include <linux/can.h>
34 #include <linux/can/dev.h>
35 #include <linux/can/error.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 */
47 enum 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 */
64 enum 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 */
117 static const struct usb_device_id usb_8dev_table[] = {
118 { USB_DEVICE(USB_8DEV_VENDOR_ID, USB_8DEV_PRODUCT_ID) },
119 { } /* Terminating entry */
120 };
121
122 MODULE_DEVICE_TABLE(usb, usb_8dev_table);
123
124 struct 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 */
132 struct 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 */
155 struct __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 */
165 struct __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 */
177 struct __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
187 static 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
196 static 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 */
207 static 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
246 failed:
247 mutex_unlock(&priv->usb_8dev_cmd_lock);
248 return err;
249 }
250
251 /* Send open command to device */
252 static 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 */
288 static 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 */
302 static 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 */
326 static 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 */
346 static 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 */
470 static 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 } else {
501 netdev_warn(priv->netdev, "frame type %d unknown",
502 msg->type);
503 }
504
505 }
506
507 /* Callback for reading data from device
508 *
509 * Check urb status, call read function and resubmit urb read operation.
510 */
511 static void usb_8dev_read_bulk_callback(struct urb *urb)
512 {
513 struct usb_8dev_priv *priv = urb->context;
514 struct net_device *netdev;
515 int retval;
516 int pos = 0;
517
518 netdev = priv->netdev;
519
520 if (!netif_device_present(netdev))
521 return;
522
523 switch (urb->status) {
524 case 0: /* success */
525 break;
526
527 case -ENOENT:
528 case -ESHUTDOWN:
529 return;
530
531 default:
532 netdev_info(netdev, "Rx URB aborted (%d)\n",
533 urb->status);
534 goto resubmit_urb;
535 }
536
537 while (pos < urb->actual_length) {
538 struct usb_8dev_rx_msg *msg;
539
540 if (pos + sizeof(struct usb_8dev_rx_msg) > urb->actual_length) {
541 netdev_err(priv->netdev, "format error\n");
542 break;
543 }
544
545 msg = (struct usb_8dev_rx_msg *)(urb->transfer_buffer + pos);
546 usb_8dev_rx_can_msg(priv, msg);
547
548 pos += sizeof(struct usb_8dev_rx_msg);
549 }
550
551 resubmit_urb:
552 usb_fill_bulk_urb(urb, priv->udev,
553 usb_rcvbulkpipe(priv->udev, USB_8DEV_ENDP_DATA_RX),
554 urb->transfer_buffer, RX_BUFFER_SIZE,
555 usb_8dev_read_bulk_callback, priv);
556
557 retval = usb_submit_urb(urb, GFP_ATOMIC);
558
559 if (retval == -ENODEV)
560 netif_device_detach(netdev);
561 else if (retval)
562 netdev_err(netdev,
563 "failed resubmitting read bulk urb: %d\n", retval);
564 }
565
566 /* Callback handler for write operations
567 *
568 * Free allocated buffers, check transmit status and
569 * calculate statistic.
570 */
571 static void usb_8dev_write_bulk_callback(struct urb *urb)
572 {
573 struct usb_8dev_tx_urb_context *context = urb->context;
574 struct usb_8dev_priv *priv;
575 struct net_device *netdev;
576
577 BUG_ON(!context);
578
579 priv = context->priv;
580 netdev = priv->netdev;
581
582 /* free up our allocated buffer */
583 usb_free_coherent(urb->dev, urb->transfer_buffer_length,
584 urb->transfer_buffer, urb->transfer_dma);
585
586 atomic_dec(&priv->active_tx_urbs);
587
588 if (!netif_device_present(netdev))
589 return;
590
591 if (urb->status)
592 netdev_info(netdev, "Tx URB aborted (%d)\n",
593 urb->status);
594
595 netdev->stats.tx_packets++;
596 netdev->stats.tx_bytes += context->dlc;
597
598 can_get_echo_skb(netdev, context->echo_index);
599
600 /* Release context */
601 context->echo_index = MAX_TX_URBS;
602
603 netif_wake_queue(netdev);
604 }
605
606 /* Send data to device */
607 static netdev_tx_t usb_8dev_start_xmit(struct sk_buff *skb,
608 struct net_device *netdev)
609 {
610 struct usb_8dev_priv *priv = netdev_priv(netdev);
611 struct net_device_stats *stats = &netdev->stats;
612 struct can_frame *cf = (struct can_frame *) skb->data;
613 struct usb_8dev_tx_msg *msg;
614 struct urb *urb;
615 struct usb_8dev_tx_urb_context *context = NULL;
616 u8 *buf;
617 int i, err;
618 size_t size = sizeof(struct usb_8dev_tx_msg);
619
620 if (can_dropped_invalid_skb(netdev, skb))
621 return NETDEV_TX_OK;
622
623 /* create a URB, and a buffer for it, and copy the data to the URB */
624 urb = usb_alloc_urb(0, GFP_ATOMIC);
625 if (!urb) {
626 netdev_err(netdev, "No memory left for URBs\n");
627 goto nomem;
628 }
629
630 buf = usb_alloc_coherent(priv->udev, size, GFP_ATOMIC,
631 &urb->transfer_dma);
632 if (!buf) {
633 netdev_err(netdev, "No memory left for USB buffer\n");
634 goto nomembuf;
635 }
636
637 memset(buf, 0, size);
638
639 msg = (struct usb_8dev_tx_msg *)buf;
640 msg->begin = USB_8DEV_DATA_START;
641 msg->flags = 0x00;
642
643 if (cf->can_id & CAN_RTR_FLAG)
644 msg->flags |= USB_8DEV_RTR;
645
646 if (cf->can_id & CAN_EFF_FLAG)
647 msg->flags |= USB_8DEV_EXTID;
648
649 msg->id = cpu_to_be32(cf->can_id & CAN_ERR_MASK);
650 msg->dlc = cf->can_dlc;
651 memcpy(msg->data, cf->data, cf->can_dlc);
652 msg->end = USB_8DEV_DATA_END;
653
654 for (i = 0; i < MAX_TX_URBS; i++) {
655 if (priv->tx_contexts[i].echo_index == MAX_TX_URBS) {
656 context = &priv->tx_contexts[i];
657 break;
658 }
659 }
660
661 /* May never happen! When this happens we'd more URBs in flight as
662 * allowed (MAX_TX_URBS).
663 */
664 if (!context)
665 goto nofreecontext;
666
667 context->priv = priv;
668 context->echo_index = i;
669 context->dlc = cf->can_dlc;
670
671 usb_fill_bulk_urb(urb, priv->udev,
672 usb_sndbulkpipe(priv->udev, USB_8DEV_ENDP_DATA_TX),
673 buf, size, usb_8dev_write_bulk_callback, context);
674 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
675 usb_anchor_urb(urb, &priv->tx_submitted);
676
677 can_put_echo_skb(skb, netdev, context->echo_index);
678
679 atomic_inc(&priv->active_tx_urbs);
680
681 err = usb_submit_urb(urb, GFP_ATOMIC);
682 if (unlikely(err))
683 goto failed;
684 else if (atomic_read(&priv->active_tx_urbs) >= MAX_TX_URBS)
685 /* Slow down tx path */
686 netif_stop_queue(netdev);
687
688 /* Release our reference to this URB, the USB core will eventually free
689 * it entirely.
690 */
691 usb_free_urb(urb);
692
693 return NETDEV_TX_OK;
694
695 nofreecontext:
696 usb_unanchor_urb(urb);
697 usb_free_coherent(priv->udev, size, buf, urb->transfer_dma);
698
699 netdev_warn(netdev, "couldn't find free context");
700
701 return NETDEV_TX_BUSY;
702
703 failed:
704 can_free_echo_skb(netdev, context->echo_index);
705
706 usb_unanchor_urb(urb);
707 usb_free_coherent(priv->udev, size, buf, urb->transfer_dma);
708
709 atomic_dec(&priv->active_tx_urbs);
710
711 if (err == -ENODEV)
712 netif_device_detach(netdev);
713 else
714 netdev_warn(netdev, "failed tx_urb %d\n", err);
715
716 nomembuf:
717 usb_free_urb(urb);
718
719 nomem:
720 dev_kfree_skb(skb);
721 stats->tx_dropped++;
722
723 return NETDEV_TX_OK;
724 }
725
726 static int usb_8dev_get_berr_counter(const struct net_device *netdev,
727 struct can_berr_counter *bec)
728 {
729 struct usb_8dev_priv *priv = netdev_priv(netdev);
730
731 bec->txerr = priv->bec.txerr;
732 bec->rxerr = priv->bec.rxerr;
733
734 return 0;
735 }
736
737 /* Start USB device */
738 static int usb_8dev_start(struct usb_8dev_priv *priv)
739 {
740 struct net_device *netdev = priv->netdev;
741 int err, i;
742
743 for (i = 0; i < MAX_RX_URBS; i++) {
744 struct urb *urb = NULL;
745 u8 *buf;
746
747 /* create a URB, and a buffer for it */
748 urb = usb_alloc_urb(0, GFP_KERNEL);
749 if (!urb) {
750 netdev_err(netdev, "No memory left for URBs\n");
751 err = -ENOMEM;
752 break;
753 }
754
755 buf = usb_alloc_coherent(priv->udev, RX_BUFFER_SIZE, GFP_KERNEL,
756 &urb->transfer_dma);
757 if (!buf) {
758 netdev_err(netdev, "No memory left for USB buffer\n");
759 usb_free_urb(urb);
760 err = -ENOMEM;
761 break;
762 }
763
764 usb_fill_bulk_urb(urb, priv->udev,
765 usb_rcvbulkpipe(priv->udev,
766 USB_8DEV_ENDP_DATA_RX),
767 buf, RX_BUFFER_SIZE,
768 usb_8dev_read_bulk_callback, priv);
769 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
770 usb_anchor_urb(urb, &priv->rx_submitted);
771
772 err = usb_submit_urb(urb, GFP_KERNEL);
773 if (err) {
774 usb_unanchor_urb(urb);
775 usb_free_coherent(priv->udev, RX_BUFFER_SIZE, buf,
776 urb->transfer_dma);
777 break;
778 }
779
780 /* Drop reference, USB core will take care of freeing it */
781 usb_free_urb(urb);
782 }
783
784 /* Did we submit any URBs */
785 if (i == 0) {
786 netdev_warn(netdev, "couldn't setup read URBs\n");
787 return err;
788 }
789
790 /* Warn if we've couldn't transmit all the URBs */
791 if (i < MAX_RX_URBS)
792 netdev_warn(netdev, "rx performance may be slow\n");
793
794 err = usb_8dev_cmd_open(priv);
795 if (err)
796 goto failed;
797
798 priv->can.state = CAN_STATE_ERROR_ACTIVE;
799
800 return 0;
801
802 failed:
803 if (err == -ENODEV)
804 netif_device_detach(priv->netdev);
805
806 netdev_warn(netdev, "couldn't submit control: %d\n", err);
807
808 return err;
809 }
810
811 /* Open USB device */
812 static int usb_8dev_open(struct net_device *netdev)
813 {
814 struct usb_8dev_priv *priv = netdev_priv(netdev);
815 int err;
816
817 /* common open */
818 err = open_candev(netdev);
819 if (err)
820 return err;
821
822 /* finally start device */
823 err = usb_8dev_start(priv);
824 if (err) {
825 if (err == -ENODEV)
826 netif_device_detach(priv->netdev);
827
828 netdev_warn(netdev, "couldn't start device: %d\n",
829 err);
830
831 close_candev(netdev);
832
833 return err;
834 }
835
836 netif_start_queue(netdev);
837
838 return 0;
839 }
840
841 static void unlink_all_urbs(struct usb_8dev_priv *priv)
842 {
843 int i;
844
845 usb_kill_anchored_urbs(&priv->rx_submitted);
846
847 usb_kill_anchored_urbs(&priv->tx_submitted);
848 atomic_set(&priv->active_tx_urbs, 0);
849
850 for (i = 0; i < MAX_TX_URBS; i++)
851 priv->tx_contexts[i].echo_index = MAX_TX_URBS;
852 }
853
854 /* Close USB device */
855 static int usb_8dev_close(struct net_device *netdev)
856 {
857 struct usb_8dev_priv *priv = netdev_priv(netdev);
858 int err = 0;
859
860 /* Send CLOSE command to CAN controller */
861 err = usb_8dev_cmd_close(priv);
862 if (err)
863 netdev_warn(netdev, "couldn't stop device");
864
865 priv->can.state = CAN_STATE_STOPPED;
866
867 netif_stop_queue(netdev);
868
869 /* Stop polling */
870 unlink_all_urbs(priv);
871
872 close_candev(netdev);
873
874 return err;
875 }
876
877 static const struct net_device_ops usb_8dev_netdev_ops = {
878 .ndo_open = usb_8dev_open,
879 .ndo_stop = usb_8dev_close,
880 .ndo_start_xmit = usb_8dev_start_xmit,
881 };
882
883 static const struct can_bittiming_const usb_8dev_bittiming_const = {
884 .name = "usb_8dev",
885 .tseg1_min = 1,
886 .tseg1_max = 16,
887 .tseg2_min = 1,
888 .tseg2_max = 8,
889 .sjw_max = 4,
890 .brp_min = 1,
891 .brp_max = 1024,
892 .brp_inc = 1,
893 };
894
895 /* Probe USB device
896 *
897 * Check device and firmware.
898 * Set supported modes and bittiming constants.
899 * Allocate some memory.
900 */
901 static int usb_8dev_probe(struct usb_interface *intf,
902 const struct usb_device_id *id)
903 {
904 struct net_device *netdev;
905 struct usb_8dev_priv *priv;
906 int i, err = -ENOMEM;
907 u32 version;
908 char buf[18];
909 struct usb_device *usbdev = interface_to_usbdev(intf);
910
911 /* product id looks strange, better we also check iProduct string */
912 if (usb_string(usbdev, usbdev->descriptor.iProduct, buf,
913 sizeof(buf)) > 0 && strcmp(buf, "USB2CAN converter")) {
914 dev_info(&usbdev->dev, "ignoring: not an USB2CAN converter\n");
915 return -ENODEV;
916 }
917
918 netdev = alloc_candev(sizeof(struct usb_8dev_priv), MAX_TX_URBS);
919 if (!netdev) {
920 dev_err(&intf->dev, "Couldn't alloc candev\n");
921 return -ENOMEM;
922 }
923
924 priv = netdev_priv(netdev);
925
926 priv->udev = usbdev;
927 priv->netdev = netdev;
928
929 priv->can.state = CAN_STATE_STOPPED;
930 priv->can.clock.freq = USB_8DEV_ABP_CLOCK;
931 priv->can.bittiming_const = &usb_8dev_bittiming_const;
932 priv->can.do_set_mode = usb_8dev_set_mode;
933 priv->can.do_get_berr_counter = usb_8dev_get_berr_counter;
934 priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK |
935 CAN_CTRLMODE_LISTENONLY |
936 CAN_CTRLMODE_ONE_SHOT;
937
938 netdev->netdev_ops = &usb_8dev_netdev_ops;
939
940 netdev->flags |= IFF_ECHO; /* we support local echo */
941
942 init_usb_anchor(&priv->rx_submitted);
943
944 init_usb_anchor(&priv->tx_submitted);
945 atomic_set(&priv->active_tx_urbs, 0);
946
947 for (i = 0; i < MAX_TX_URBS; i++)
948 priv->tx_contexts[i].echo_index = MAX_TX_URBS;
949
950 priv->cmd_msg_buffer = kzalloc(sizeof(struct usb_8dev_cmd_msg),
951 GFP_KERNEL);
952 if (!priv->cmd_msg_buffer) {
953 netdev_err(netdev, "Couldn't alloc Tx buffer\n");
954 goto cleanup_candev;
955 }
956
957 usb_set_intfdata(intf, priv);
958
959 SET_NETDEV_DEV(netdev, &intf->dev);
960
961 mutex_init(&priv->usb_8dev_cmd_lock);
962
963 err = register_candev(netdev);
964 if (err) {
965 netdev_err(netdev,
966 "couldn't register CAN device: %d\n", err);
967 goto cleanup_cmd_msg_buffer;
968 }
969
970 err = usb_8dev_cmd_version(priv, &version);
971 if (err) {
972 netdev_err(netdev, "can't get firmware version\n");
973 goto cleanup_cmd_msg_buffer;
974 } else {
975 netdev_info(netdev,
976 "firmware: %d.%d, hardware: %d.%d\n",
977 (version>>24) & 0xff, (version>>16) & 0xff,
978 (version>>8) & 0xff, version & 0xff);
979 }
980
981 return 0;
982
983 cleanup_cmd_msg_buffer:
984 kfree(priv->cmd_msg_buffer);
985
986 cleanup_candev:
987 free_candev(netdev);
988
989 return err;
990
991 }
992
993 /* Called by the usb core when driver is unloaded or device is removed */
994 static void usb_8dev_disconnect(struct usb_interface *intf)
995 {
996 struct usb_8dev_priv *priv = usb_get_intfdata(intf);
997
998 usb_set_intfdata(intf, NULL);
999
1000 if (priv) {
1001 netdev_info(priv->netdev, "device disconnected\n");
1002
1003 unregister_netdev(priv->netdev);
1004 free_candev(priv->netdev);
1005
1006 unlink_all_urbs(priv);
1007 }
1008
1009 }
1010
1011 static struct usb_driver usb_8dev_driver = {
1012 .name = "usb_8dev",
1013 .probe = usb_8dev_probe,
1014 .disconnect = usb_8dev_disconnect,
1015 .id_table = usb_8dev_table,
1016 };
1017
1018 module_usb_driver(usb_8dev_driver);
1019
1020 MODULE_AUTHOR("Bernd Krumboeck <krumboeck@universalnet.at>");
1021 MODULE_DESCRIPTION("CAN driver for 8 devices USB2CAN interfaces");
1022 MODULE_LICENSE("GPL v2");
Linux kernel - Deliverables
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