1 /*
2 * CAN driver for esd CAN-USB/2
3 *
4 * Copyright (C) 2010 Matthias Fuchs <matthias.fuchs@esd.eu>, esd gmbh
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; if not, write to the Free Software Foundation, Inc.,
17 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
18 */
19 #include <linux/init.h>
20 #include <linux/signal.h>
21 #include <linux/slab.h>
22 #include <linux/module.h>
23 #include <linux/netdevice.h>
24 #include <linux/usb.h>
25
26 #include <linux/can.h>
27 #include <linux/can/dev.h>
28 #include <linux/can/error.h>
29
30 MODULE_AUTHOR("Matthias Fuchs <matthias.fuchs@esd.eu>");
31 MODULE_DESCRIPTION("CAN driver for esd CAN-USB/2 interfaces");
32 MODULE_LICENSE("GPL v2");
33
34 /* Define these values to match your devices */
35 #define USB_ESDGMBH_VENDOR_ID 0x0ab4
36 #define USB_CANUSB2_PRODUCT_ID 0x0010
37
38 #define ESD_USB2_CAN_CLOCK 60000000
39 #define ESD_USB2_MAX_NETS 2
40
41 /* USB2 commands */
42 #define CMD_VERSION 1 /* also used for VERSION_REPLY */
43 #define CMD_CAN_RX 2 /* device to host only */
44 #define CMD_CAN_TX 3 /* also used for TX_DONE */
45 #define CMD_SETBAUD 4 /* also used for SETBAUD_REPLY */
46 #define CMD_TS 5 /* also used for TS_REPLY */
47 #define CMD_IDADD 6 /* also used for IDADD_REPLY */
48
49 /* esd CAN message flags - dlc field */
50 #define ESD_RTR 0x10
51
52 /* esd CAN message flags - id field */
53 #define ESD_EXTID 0x20000000
54 #define ESD_EVENT 0x40000000
55 #define ESD_IDMASK 0x1fffffff
56
57 /* esd CAN event ids used by this driver */
58 #define ESD_EV_CAN_ERROR_EXT 2
59
60 /* baudrate message flags */
61 #define ESD_USB2_UBR 0x80000000
62 #define ESD_USB2_LOM 0x40000000
63 #define ESD_USB2_NO_BAUDRATE 0x7fffffff
64 #define ESD_USB2_TSEG1_MIN 1
65 #define ESD_USB2_TSEG1_MAX 16
66 #define ESD_USB2_TSEG1_SHIFT 16
67 #define ESD_USB2_TSEG2_MIN 1
68 #define ESD_USB2_TSEG2_MAX 8
69 #define ESD_USB2_TSEG2_SHIFT 20
70 #define ESD_USB2_SJW_MAX 4
71 #define ESD_USB2_SJW_SHIFT 14
72 #define ESD_USB2_BRP_MIN 1
73 #define ESD_USB2_BRP_MAX 1024
74 #define ESD_USB2_BRP_INC 1
75 #define ESD_USB2_3_SAMPLES 0x00800000
76
77 /* esd IDADD message */
78 #define ESD_ID_ENABLE 0x80
79 #define ESD_MAX_ID_SEGMENT 64
80
81 /* SJA1000 ECC register (emulated by usb2 firmware) */
82 #define SJA1000_ECC_SEG 0x1F
83 #define SJA1000_ECC_DIR 0x20
84 #define SJA1000_ECC_ERR 0x06
85 #define SJA1000_ECC_BIT 0x00
86 #define SJA1000_ECC_FORM 0x40
87 #define SJA1000_ECC_STUFF 0x80
88 #define SJA1000_ECC_MASK 0xc0
89
90 /* esd bus state event codes */
91 #define ESD_BUSSTATE_MASK 0xc0
92 #define ESD_BUSSTATE_WARN 0x40
93 #define ESD_BUSSTATE_ERRPASSIVE 0x80
94 #define ESD_BUSSTATE_BUSOFF 0xc0
95
96 #define RX_BUFFER_SIZE 1024
97 #define MAX_RX_URBS 4
98 #define MAX_TX_URBS 16 /* must be power of 2 */
99
100 struct header_msg {
101 u8 len; /* len is always the total message length in 32bit words */
102 u8 cmd;
103 u8 rsvd[2];
104 };
105
106 struct version_msg {
107 u8 len;
108 u8 cmd;
109 u8 rsvd;
110 u8 flags;
111 __le32 drv_version;
112 };
113
114 struct version_reply_msg {
115 u8 len;
116 u8 cmd;
117 u8 nets;
118 u8 features;
119 __le32 version;
120 u8 name[16];
121 __le32 rsvd;
122 __le32 ts;
123 };
124
125 struct rx_msg {
126 u8 len;
127 u8 cmd;
128 u8 net;
129 u8 dlc;
130 __le32 ts;
131 __le32 id; /* upper 3 bits contain flags */
132 u8 data[8];
133 };
134
135 struct tx_msg {
136 u8 len;
137 u8 cmd;
138 u8 net;
139 u8 dlc;
140 __le32 hnd;
141 __le32 id; /* upper 3 bits contain flags */
142 u8 data[8];
143 };
144
145 struct tx_done_msg {
146 u8 len;
147 u8 cmd;
148 u8 net;
149 u8 status;
150 __le32 hnd;
151 __le32 ts;
152 };
153
154 struct id_filter_msg {
155 u8 len;
156 u8 cmd;
157 u8 net;
158 u8 option;
159 __le32 mask[ESD_MAX_ID_SEGMENT + 1];
160 };
161
162 struct set_baudrate_msg {
163 u8 len;
164 u8 cmd;
165 u8 net;
166 u8 rsvd;
167 __le32 baud;
168 };
169
170 /* Main message type used between library and application */
171 struct __attribute__ ((packed)) esd_usb2_msg {
172 union {
173 struct header_msg hdr;
174 struct version_msg version;
175 struct version_reply_msg version_reply;
176 struct rx_msg rx;
177 struct tx_msg tx;
178 struct tx_done_msg txdone;
179 struct set_baudrate_msg setbaud;
180 struct id_filter_msg filter;
181 } msg;
182 };
183
184 static struct usb_device_id esd_usb2_table[] = {
185 {USB_DEVICE(USB_ESDGMBH_VENDOR_ID, USB_CANUSB2_PRODUCT_ID)},
186 {}
187 };
188 MODULE_DEVICE_TABLE(usb, esd_usb2_table);
189
190 struct esd_usb2_net_priv;
191
192 struct esd_tx_urb_context {
193 struct esd_usb2_net_priv *priv;
194 u32 echo_index;
195 int dlc;
196 };
197
198 struct esd_usb2 {
199 struct usb_device *udev;
200 struct esd_usb2_net_priv *nets[ESD_USB2_MAX_NETS];
201
202 struct usb_anchor rx_submitted;
203
204 int net_count;
205 u32 version;
206 int rxinitdone;
207 };
208
209 struct esd_usb2_net_priv {
210 struct can_priv can; /* must be the first member */
211
212 atomic_t active_tx_jobs;
213 struct usb_anchor tx_submitted;
214 struct esd_tx_urb_context tx_contexts[MAX_TX_URBS];
215
216 int open_time;
217 struct esd_usb2 *usb2;
218 struct net_device *netdev;
219 int index;
220 u8 old_state;
221 struct can_berr_counter bec;
222 };
223
esd_usb2_rx_event(struct esd_usb2_net_priv * priv,struct esd_usb2_msg * msg)224 static void esd_usb2_rx_event(struct esd_usb2_net_priv *priv,
225 struct esd_usb2_msg *msg)
226 {
227 struct net_device_stats *stats = &priv->netdev->stats;
228 struct can_frame *cf;
229 struct sk_buff *skb;
230 u32 id = le32_to_cpu(msg->msg.rx.id) & ESD_IDMASK;
231
232 if (id == ESD_EV_CAN_ERROR_EXT) {
233 u8 state = msg->msg.rx.data[0];
234 u8 ecc = msg->msg.rx.data[1];
235 u8 txerr = msg->msg.rx.data[2];
236 u8 rxerr = msg->msg.rx.data[3];
237
238 skb = alloc_can_err_skb(priv->netdev, &cf);
239 if (skb == NULL) {
240 stats->rx_dropped++;
241 return;
242 }
243
244 if (state != priv->old_state) {
245 priv->old_state = state;
246
247 switch (state & ESD_BUSSTATE_MASK) {
248 case ESD_BUSSTATE_BUSOFF:
249 priv->can.state = CAN_STATE_BUS_OFF;
250 cf->can_id |= CAN_ERR_BUSOFF;
251 can_bus_off(priv->netdev);
252 break;
253 case ESD_BUSSTATE_WARN:
254 priv->can.state = CAN_STATE_ERROR_WARNING;
255 priv->can.can_stats.error_warning++;
256 break;
257 case ESD_BUSSTATE_ERRPASSIVE:
258 priv->can.state = CAN_STATE_ERROR_PASSIVE;
259 priv->can.can_stats.error_passive++;
260 break;
261 default:
262 priv->can.state = CAN_STATE_ERROR_ACTIVE;
263 break;
264 }
265 } else {
266 priv->can.can_stats.bus_error++;
267 stats->rx_errors++;
268
269 cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
270
271 switch (ecc & SJA1000_ECC_MASK) {
272 case SJA1000_ECC_BIT:
273 cf->data[2] |= CAN_ERR_PROT_BIT;
274 break;
275 case SJA1000_ECC_FORM:
276 cf->data[2] |= CAN_ERR_PROT_FORM;
277 break;
278 case SJA1000_ECC_STUFF:
279 cf->data[2] |= CAN_ERR_PROT_STUFF;
280 break;
281 default:
282 cf->data[2] |= CAN_ERR_PROT_UNSPEC;
283 cf->data[3] = ecc & SJA1000_ECC_SEG;
284 break;
285 }
286
287 /* Error occurred during transmission? */
288 if (!(ecc & SJA1000_ECC_DIR))
289 cf->data[2] |= CAN_ERR_PROT_TX;
290
291 if (priv->can.state == CAN_STATE_ERROR_WARNING ||
292 priv->can.state == CAN_STATE_ERROR_PASSIVE) {
293 cf->data[1] = (txerr > rxerr) ?
294 CAN_ERR_CRTL_TX_PASSIVE :
295 CAN_ERR_CRTL_RX_PASSIVE;
296 }
297 cf->data[6] = txerr;
298 cf->data[7] = rxerr;
299 }
300
301 netif_rx(skb);
302
303 priv->bec.txerr = txerr;
304 priv->bec.rxerr = rxerr;
305
306 stats->rx_packets++;
307 stats->rx_bytes += cf->can_dlc;
308 }
309 }
310
esd_usb2_rx_can_msg(struct esd_usb2_net_priv * priv,struct esd_usb2_msg * msg)311 static void esd_usb2_rx_can_msg(struct esd_usb2_net_priv *priv,
312 struct esd_usb2_msg *msg)
313 {
314 struct net_device_stats *stats = &priv->netdev->stats;
315 struct can_frame *cf;
316 struct sk_buff *skb;
317 int i;
318 u32 id;
319
320 if (!netif_device_present(priv->netdev))
321 return;
322
323 id = le32_to_cpu(msg->msg.rx.id);
324
325 if (id & ESD_EVENT) {
326 esd_usb2_rx_event(priv, msg);
327 } else {
328 skb = alloc_can_skb(priv->netdev, &cf);
329 if (skb == NULL) {
330 stats->rx_dropped++;
331 return;
332 }
333
334 cf->can_id = id & ESD_IDMASK;
335 cf->can_dlc = get_can_dlc(msg->msg.rx.dlc);
336
337 if (id & ESD_EXTID)
338 cf->can_id |= CAN_EFF_FLAG;
339
340 if (msg->msg.rx.dlc & ESD_RTR) {
341 cf->can_id |= CAN_RTR_FLAG;
342 } else {
343 for (i = 0; i < cf->can_dlc; i++)
344 cf->data[i] = msg->msg.rx.data[i];
345 }
346
347 netif_rx(skb);
348
349 stats->rx_packets++;
350 stats->rx_bytes += cf->can_dlc;
351 }
352
353 return;
354 }
355
esd_usb2_tx_done_msg(struct esd_usb2_net_priv * priv,struct esd_usb2_msg * msg)356 static void esd_usb2_tx_done_msg(struct esd_usb2_net_priv *priv,
357 struct esd_usb2_msg *msg)
358 {
359 struct net_device_stats *stats = &priv->netdev->stats;
360 struct net_device *netdev = priv->netdev;
361 struct esd_tx_urb_context *context;
362
363 if (!netif_device_present(netdev))
364 return;
365
366 context = &priv->tx_contexts[msg->msg.txdone.hnd & (MAX_TX_URBS - 1)];
367
368 if (!msg->msg.txdone.status) {
369 stats->tx_packets++;
370 stats->tx_bytes += context->dlc;
371 can_get_echo_skb(netdev, context->echo_index);
372 } else {
373 stats->tx_errors++;
374 can_free_echo_skb(netdev, context->echo_index);
375 }
376
377 /* Release context */
378 context->echo_index = MAX_TX_URBS;
379 atomic_dec(&priv->active_tx_jobs);
380
381 netif_wake_queue(netdev);
382 }
383
esd_usb2_read_bulk_callback(struct urb * urb)384 static void esd_usb2_read_bulk_callback(struct urb *urb)
385 {
386 struct esd_usb2 *dev = urb->context;
387 int retval;
388 int pos = 0;
389 int i;
390
391 switch (urb->status) {
392 case 0: /* success */
393 break;
394
395 case -ENOENT:
396 case -ESHUTDOWN:
397 return;
398
399 default:
400 dev_info(dev->udev->dev.parent,
401 "Rx URB aborted (%d)\n", urb->status);
402 goto resubmit_urb;
403 }
404
405 while (pos < urb->actual_length) {
406 struct esd_usb2_msg *msg;
407
408 msg = (struct esd_usb2_msg *)(urb->transfer_buffer + pos);
409
410 switch (msg->msg.hdr.cmd) {
411 case CMD_CAN_RX:
412 esd_usb2_rx_can_msg(dev->nets[msg->msg.rx.net], msg);
413 break;
414
415 case CMD_CAN_TX:
416 esd_usb2_tx_done_msg(dev->nets[msg->msg.txdone.net],
417 msg);
418 break;
419 }
420
421 pos += msg->msg.hdr.len << 2;
422
423 if (pos > urb->actual_length) {
424 dev_err(dev->udev->dev.parent, "format error\n");
425 break;
426 }
427 }
428
429 resubmit_urb:
430 usb_fill_bulk_urb(urb, dev->udev, usb_rcvbulkpipe(dev->udev, 1),
431 urb->transfer_buffer, RX_BUFFER_SIZE,
432 esd_usb2_read_bulk_callback, dev);
433
434 retval = usb_submit_urb(urb, GFP_ATOMIC);
435 if (retval == -ENODEV) {
436 for (i = 0; i < dev->net_count; i++) {
437 if (dev->nets[i])
438 netif_device_detach(dev->nets[i]->netdev);
439 }
440 } else if (retval) {
441 dev_err(dev->udev->dev.parent,
442 "failed resubmitting read bulk urb: %d\n", retval);
443 }
444
445 return;
446 }
447
448 /*
449 * callback for bulk IN urb
450 */
esd_usb2_write_bulk_callback(struct urb * urb)451 static void esd_usb2_write_bulk_callback(struct urb *urb)
452 {
453 struct esd_tx_urb_context *context = urb->context;
454 struct esd_usb2_net_priv *priv;
455 struct esd_usb2 *dev;
456 struct net_device *netdev;
457 size_t size = sizeof(struct esd_usb2_msg);
458
459 WARN_ON(!context);
460
461 priv = context->priv;
462 netdev = priv->netdev;
463 dev = priv->usb2;
464
465 /* free up our allocated buffer */
466 usb_free_coherent(urb->dev, size,
467 urb->transfer_buffer, urb->transfer_dma);
468
469 if (!netif_device_present(netdev))
470 return;
471
472 if (urb->status)
473 dev_info(netdev->dev.parent, "Tx URB aborted (%d)\n",
474 urb->status);
475
476 netdev->trans_start = jiffies;
477 }
478
show_firmware(struct device * d,struct device_attribute * attr,char * buf)479 static ssize_t show_firmware(struct device *d,
480 struct device_attribute *attr, char *buf)
481 {
482 struct usb_interface *intf = to_usb_interface(d);
483 struct esd_usb2 *dev = usb_get_intfdata(intf);
484
485 return sprintf(buf, "%d.%d.%d\n",
486 (dev->version >> 12) & 0xf,
487 (dev->version >> 8) & 0xf,
488 dev->version & 0xff);
489 }
490 static DEVICE_ATTR(firmware, S_IRUGO, show_firmware, NULL);
491
show_hardware(struct device * d,struct device_attribute * attr,char * buf)492 static ssize_t show_hardware(struct device *d,
493 struct device_attribute *attr, char *buf)
494 {
495 struct usb_interface *intf = to_usb_interface(d);
496 struct esd_usb2 *dev = usb_get_intfdata(intf);
497
498 return sprintf(buf, "%d.%d.%d\n",
499 (dev->version >> 28) & 0xf,
500 (dev->version >> 24) & 0xf,
501 (dev->version >> 16) & 0xff);
502 }
503 static DEVICE_ATTR(hardware, S_IRUGO, show_hardware, NULL);
504
show_nets(struct device * d,struct device_attribute * attr,char * buf)505 static ssize_t show_nets(struct device *d,
506 struct device_attribute *attr, char *buf)
507 {
508 struct usb_interface *intf = to_usb_interface(d);
509 struct esd_usb2 *dev = usb_get_intfdata(intf);
510
511 return sprintf(buf, "%d", dev->net_count);
512 }
513 static DEVICE_ATTR(nets, S_IRUGO, show_nets, NULL);
514
esd_usb2_send_msg(struct esd_usb2 * dev,struct esd_usb2_msg * msg)515 static int esd_usb2_send_msg(struct esd_usb2 *dev, struct esd_usb2_msg *msg)
516 {
517 int actual_length;
518
519 return usb_bulk_msg(dev->udev,
520 usb_sndbulkpipe(dev->udev, 2),
521 msg,
522 msg->msg.hdr.len << 2,
523 &actual_length,
524 1000);
525 }
526
esd_usb2_wait_msg(struct esd_usb2 * dev,struct esd_usb2_msg * msg)527 static int esd_usb2_wait_msg(struct esd_usb2 *dev,
528 struct esd_usb2_msg *msg)
529 {
530 int actual_length;
531
532 return usb_bulk_msg(dev->udev,
533 usb_rcvbulkpipe(dev->udev, 1),
534 msg,
535 sizeof(*msg),
536 &actual_length,
537 1000);
538 }
539
esd_usb2_setup_rx_urbs(struct esd_usb2 * dev)540 static int esd_usb2_setup_rx_urbs(struct esd_usb2 *dev)
541 {
542 int i, err = 0;
543
544 if (dev->rxinitdone)
545 return 0;
546
547 for (i = 0; i < MAX_RX_URBS; i++) {
548 struct urb *urb = NULL;
549 u8 *buf = NULL;
550
551 /* create a URB, and a buffer for it */
552 urb = usb_alloc_urb(0, GFP_KERNEL);
553 if (!urb) {
554 dev_warn(dev->udev->dev.parent,
555 "No memory left for URBs\n");
556 err = -ENOMEM;
557 break;
558 }
559
560 buf = usb_alloc_coherent(dev->udev, RX_BUFFER_SIZE, GFP_KERNEL,
561 &urb->transfer_dma);
562 if (!buf) {
563 dev_warn(dev->udev->dev.parent,
564 "No memory left for USB buffer\n");
565 err = -ENOMEM;
566 goto freeurb;
567 }
568
569 usb_fill_bulk_urb(urb, dev->udev,
570 usb_rcvbulkpipe(dev->udev, 1),
571 buf, RX_BUFFER_SIZE,
572 esd_usb2_read_bulk_callback, dev);
573 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
574 usb_anchor_urb(urb, &dev->rx_submitted);
575
576 err = usb_submit_urb(urb, GFP_KERNEL);
577 if (err) {
578 usb_unanchor_urb(urb);
579 usb_free_coherent(dev->udev, RX_BUFFER_SIZE, buf,
580 urb->transfer_dma);
581 }
582
583 freeurb:
584 /* Drop reference, USB core will take care of freeing it */
585 usb_free_urb(urb);
586 if (err)
587 break;
588 }
589
590 /* Did we submit any URBs */
591 if (i == 0) {
592 dev_err(dev->udev->dev.parent, "couldn't setup read URBs\n");
593 return err;
594 }
595
596 /* Warn if we've couldn't transmit all the URBs */
597 if (i < MAX_RX_URBS) {
598 dev_warn(dev->udev->dev.parent,
599 "rx performance may be slow\n");
600 }
601
602 dev->rxinitdone = 1;
603 return 0;
604 }
605
606 /*
607 * Start interface
608 */
esd_usb2_start(struct esd_usb2_net_priv * priv)609 static int esd_usb2_start(struct esd_usb2_net_priv *priv)
610 {
611 struct esd_usb2 *dev = priv->usb2;
612 struct net_device *netdev = priv->netdev;
613 struct esd_usb2_msg msg;
614 int err, i;
615
616 /*
617 * Enable all IDs
618 * The IDADD message takes up to 64 32 bit bitmasks (2048 bits).
619 * Each bit represents one 11 bit CAN identifier. A set bit
620 * enables reception of the corresponding CAN identifier. A cleared
621 * bit disabled this identifier. An additional bitmask value
622 * following the CAN 2.0A bits is used to enable reception of
623 * extended CAN frames. Only the LSB of this final mask is checked
624 * for the complete 29 bit ID range. The IDADD message also allows
625 * filter configuration for an ID subset. In this case you can add
626 * the number of the starting bitmask (0..64) to the filter.option
627 * field followed by only some bitmasks.
628 */
629 msg.msg.hdr.cmd = CMD_IDADD;
630 msg.msg.hdr.len = 2 + ESD_MAX_ID_SEGMENT;
631 msg.msg.filter.net = priv->index;
632 msg.msg.filter.option = ESD_ID_ENABLE; /* start with segment 0 */
633 for (i = 0; i < ESD_MAX_ID_SEGMENT; i++)
634 msg.msg.filter.mask[i] = cpu_to_le32(0xffffffff);
635 /* enable 29bit extended IDs */
636 msg.msg.filter.mask[ESD_MAX_ID_SEGMENT] = cpu_to_le32(0x00000001);
637
638 err = esd_usb2_send_msg(dev, &msg);
639 if (err)
640 goto failed;
641
642 err = esd_usb2_setup_rx_urbs(dev);
643 if (err)
644 goto failed;
645
646 priv->can.state = CAN_STATE_ERROR_ACTIVE;
647
648 return 0;
649
650 failed:
651 if (err == -ENODEV)
652 netif_device_detach(netdev);
653
654 dev_err(netdev->dev.parent, "couldn't start device: %d\n", err);
655
656 return err;
657 }
658
unlink_all_urbs(struct esd_usb2 * dev)659 static void unlink_all_urbs(struct esd_usb2 *dev)
660 {
661 struct esd_usb2_net_priv *priv;
662 int i, j;
663
664 usb_kill_anchored_urbs(&dev->rx_submitted);
665 for (i = 0; i < dev->net_count; i++) {
666 priv = dev->nets[i];
667 if (priv) {
668 usb_kill_anchored_urbs(&priv->tx_submitted);
669 atomic_set(&priv->active_tx_jobs, 0);
670
671 for (j = 0; j < MAX_TX_URBS; j++)
672 priv->tx_contexts[j].echo_index = MAX_TX_URBS;
673 }
674 }
675 }
676
esd_usb2_open(struct net_device * netdev)677 static int esd_usb2_open(struct net_device *netdev)
678 {
679 struct esd_usb2_net_priv *priv = netdev_priv(netdev);
680 int err;
681
682 /* common open */
683 err = open_candev(netdev);
684 if (err)
685 return err;
686
687 /* finally start device */
688 err = esd_usb2_start(priv);
689 if (err) {
690 dev_warn(netdev->dev.parent,
691 "couldn't start device: %d\n", err);
692 close_candev(netdev);
693 return err;
694 }
695
696 priv->open_time = jiffies;
697
698 netif_start_queue(netdev);
699
700 return 0;
701 }
702
esd_usb2_start_xmit(struct sk_buff * skb,struct net_device * netdev)703 static netdev_tx_t esd_usb2_start_xmit(struct sk_buff *skb,
704 struct net_device *netdev)
705 {
706 struct esd_usb2_net_priv *priv = netdev_priv(netdev);
707 struct esd_usb2 *dev = priv->usb2;
708 struct esd_tx_urb_context *context = NULL;
709 struct net_device_stats *stats = &netdev->stats;
710 struct can_frame *cf = (struct can_frame *)skb->data;
711 struct esd_usb2_msg *msg;
712 struct urb *urb;
713 u8 *buf;
714 int i, err;
715 int ret = NETDEV_TX_OK;
716 size_t size = sizeof(struct esd_usb2_msg);
717
718 if (can_dropped_invalid_skb(netdev, skb))
719 return NETDEV_TX_OK;
720
721 /* create a URB, and a buffer for it, and copy the data to the URB */
722 urb = usb_alloc_urb(0, GFP_ATOMIC);
723 if (!urb) {
724 dev_err(netdev->dev.parent, "No memory left for URBs\n");
725 stats->tx_dropped++;
726 dev_kfree_skb(skb);
727 goto nourbmem;
728 }
729
730 buf = usb_alloc_coherent(dev->udev, size, GFP_ATOMIC,
731 &urb->transfer_dma);
732 if (!buf) {
733 dev_err(netdev->dev.parent, "No memory left for USB buffer\n");
734 stats->tx_dropped++;
735 dev_kfree_skb(skb);
736 goto nobufmem;
737 }
738
739 msg = (struct esd_usb2_msg *)buf;
740
741 msg->msg.hdr.len = 3; /* minimal length */
742 msg->msg.hdr.cmd = CMD_CAN_TX;
743 msg->msg.tx.net = priv->index;
744 msg->msg.tx.dlc = cf->can_dlc;
745 msg->msg.tx.id = cpu_to_le32(cf->can_id & CAN_ERR_MASK);
746
747 if (cf->can_id & CAN_RTR_FLAG)
748 msg->msg.tx.dlc |= ESD_RTR;
749
750 if (cf->can_id & CAN_EFF_FLAG)
751 msg->msg.tx.id |= cpu_to_le32(ESD_EXTID);
752
753 for (i = 0; i < cf->can_dlc; i++)
754 msg->msg.tx.data[i] = cf->data[i];
755
756 msg->msg.hdr.len += (cf->can_dlc + 3) >> 2;
757
758 for (i = 0; i < MAX_TX_URBS; i++) {
759 if (priv->tx_contexts[i].echo_index == MAX_TX_URBS) {
760 context = &priv->tx_contexts[i];
761 break;
762 }
763 }
764
765 /*
766 * This may never happen.
767 */
768 if (!context) {
769 dev_warn(netdev->dev.parent, "couldn't find free context\n");
770 ret = NETDEV_TX_BUSY;
771 goto releasebuf;
772 }
773
774 context->priv = priv;
775 context->echo_index = i;
776 context->dlc = cf->can_dlc;
777
778 /* hnd must not be 0 - MSB is stripped in txdone handling */
779 msg->msg.tx.hnd = 0x80000000 | i; /* returned in TX done message */
780
781 usb_fill_bulk_urb(urb, dev->udev, usb_sndbulkpipe(dev->udev, 2), buf,
782 msg->msg.hdr.len << 2,
783 esd_usb2_write_bulk_callback, context);
784
785 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
786
787 usb_anchor_urb(urb, &priv->tx_submitted);
788
789 can_put_echo_skb(skb, netdev, context->echo_index);
790
791 atomic_inc(&priv->active_tx_jobs);
792
793 /* Slow down tx path */
794 if (atomic_read(&priv->active_tx_jobs) >= MAX_TX_URBS)
795 netif_stop_queue(netdev);
796
797 err = usb_submit_urb(urb, GFP_ATOMIC);
798 if (err) {
799 can_free_echo_skb(netdev, context->echo_index);
800
801 atomic_dec(&priv->active_tx_jobs);
802 usb_unanchor_urb(urb);
803
804 stats->tx_dropped++;
805
806 if (err == -ENODEV)
807 netif_device_detach(netdev);
808 else
809 dev_warn(netdev->dev.parent, "failed tx_urb %d\n", err);
810
811 goto releasebuf;
812 }
813
814 netdev->trans_start = jiffies;
815
816 /*
817 * Release our reference to this URB, the USB core will eventually free
818 * it entirely.
819 */
820 usb_free_urb(urb);
821
822 return NETDEV_TX_OK;
823
824 releasebuf:
825 usb_free_coherent(dev->udev, size, buf, urb->transfer_dma);
826
827 nobufmem:
828 usb_free_urb(urb);
829
830 nourbmem:
831 return ret;
832 }
833
esd_usb2_close(struct net_device * netdev)834 static int esd_usb2_close(struct net_device *netdev)
835 {
836 struct esd_usb2_net_priv *priv = netdev_priv(netdev);
837 struct esd_usb2_msg msg;
838 int i;
839
840 /* Disable all IDs (see esd_usb2_start()) */
841 msg.msg.hdr.cmd = CMD_IDADD;
842 msg.msg.hdr.len = 2 + ESD_MAX_ID_SEGMENT;
843 msg.msg.filter.net = priv->index;
844 msg.msg.filter.option = ESD_ID_ENABLE; /* start with segment 0 */
845 for (i = 0; i <= ESD_MAX_ID_SEGMENT; i++)
846 msg.msg.filter.mask[i] = 0;
847 if (esd_usb2_send_msg(priv->usb2, &msg) < 0)
848 dev_err(netdev->dev.parent, "sending idadd message failed\n");
849
850 /* set CAN controller to reset mode */
851 msg.msg.hdr.len = 2;
852 msg.msg.hdr.cmd = CMD_SETBAUD;
853 msg.msg.setbaud.net = priv->index;
854 msg.msg.setbaud.rsvd = 0;
855 msg.msg.setbaud.baud = cpu_to_le32(ESD_USB2_NO_BAUDRATE);
856 if (esd_usb2_send_msg(priv->usb2, &msg) < 0)
857 dev_err(netdev->dev.parent, "sending setbaud message failed\n");
858
859 priv->can.state = CAN_STATE_STOPPED;
860
861 netif_stop_queue(netdev);
862
863 close_candev(netdev);
864
865 priv->open_time = 0;
866
867 return 0;
868 }
869
870 static const struct net_device_ops esd_usb2_netdev_ops = {
871 .ndo_open = esd_usb2_open,
872 .ndo_stop = esd_usb2_close,
873 .ndo_start_xmit = esd_usb2_start_xmit,
874 };
875
876 static struct can_bittiming_const esd_usb2_bittiming_const = {
877 .name = "esd_usb2",
878 .tseg1_min = ESD_USB2_TSEG1_MIN,
879 .tseg1_max = ESD_USB2_TSEG1_MAX,
880 .tseg2_min = ESD_USB2_TSEG2_MIN,
881 .tseg2_max = ESD_USB2_TSEG2_MAX,
882 .sjw_max = ESD_USB2_SJW_MAX,
883 .brp_min = ESD_USB2_BRP_MIN,
884 .brp_max = ESD_USB2_BRP_MAX,
885 .brp_inc = ESD_USB2_BRP_INC,
886 };
887
esd_usb2_set_bittiming(struct net_device * netdev)888 static int esd_usb2_set_bittiming(struct net_device *netdev)
889 {
890 struct esd_usb2_net_priv *priv = netdev_priv(netdev);
891 struct can_bittiming *bt = &priv->can.bittiming;
892 struct esd_usb2_msg msg;
893 u32 canbtr;
894
895 canbtr = ESD_USB2_UBR;
896 canbtr |= (bt->brp - 1) & (ESD_USB2_BRP_MAX - 1);
897 canbtr |= ((bt->sjw - 1) & (ESD_USB2_SJW_MAX - 1))
898 << ESD_USB2_SJW_SHIFT;
899 canbtr |= ((bt->prop_seg + bt->phase_seg1 - 1)
900 & (ESD_USB2_TSEG1_MAX - 1))
901 << ESD_USB2_TSEG1_SHIFT;
902 canbtr |= ((bt->phase_seg2 - 1) & (ESD_USB2_TSEG2_MAX - 1))
903 << ESD_USB2_TSEG2_SHIFT;
904 if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
905 canbtr |= ESD_USB2_3_SAMPLES;
906
907 msg.msg.hdr.len = 2;
908 msg.msg.hdr.cmd = CMD_SETBAUD;
909 msg.msg.setbaud.net = priv->index;
910 msg.msg.setbaud.rsvd = 0;
911 msg.msg.setbaud.baud = cpu_to_le32(canbtr);
912
913 dev_info(netdev->dev.parent, "setting BTR=%#x\n", canbtr);
914
915 return esd_usb2_send_msg(priv->usb2, &msg);
916 }
917
esd_usb2_get_berr_counter(const struct net_device * netdev,struct can_berr_counter * bec)918 static int esd_usb2_get_berr_counter(const struct net_device *netdev,
919 struct can_berr_counter *bec)
920 {
921 struct esd_usb2_net_priv *priv = netdev_priv(netdev);
922
923 bec->txerr = priv->bec.txerr;
924 bec->rxerr = priv->bec.rxerr;
925
926 return 0;
927 }
928
esd_usb2_set_mode(struct net_device * netdev,enum can_mode mode)929 static int esd_usb2_set_mode(struct net_device *netdev, enum can_mode mode)
930 {
931 struct esd_usb2_net_priv *priv = netdev_priv(netdev);
932
933 if (!priv->open_time)
934 return -EINVAL;
935
936 switch (mode) {
937 case CAN_MODE_START:
938 netif_wake_queue(netdev);
939 break;
940
941 default:
942 return -EOPNOTSUPP;
943 }
944
945 return 0;
946 }
947
esd_usb2_probe_one_net(struct usb_interface * intf,int index)948 static int esd_usb2_probe_one_net(struct usb_interface *intf, int index)
949 {
950 struct esd_usb2 *dev = usb_get_intfdata(intf);
951 struct net_device *netdev;
952 struct esd_usb2_net_priv *priv;
953 int err = 0;
954 int i;
955
956 netdev = alloc_candev(sizeof(*priv), MAX_TX_URBS);
957 if (!netdev) {
958 dev_err(&intf->dev, "couldn't alloc candev\n");
959 err = -ENOMEM;
960 goto done;
961 }
962
963 priv = netdev_priv(netdev);
964
965 init_usb_anchor(&priv->tx_submitted);
966 atomic_set(&priv->active_tx_jobs, 0);
967
968 for (i = 0; i < MAX_TX_URBS; i++)
969 priv->tx_contexts[i].echo_index = MAX_TX_URBS;
970
971 priv->usb2 = dev;
972 priv->netdev = netdev;
973 priv->index = index;
974
975 priv->can.state = CAN_STATE_STOPPED;
976 priv->can.clock.freq = ESD_USB2_CAN_CLOCK;
977 priv->can.bittiming_const = &esd_usb2_bittiming_const;
978 priv->can.do_set_bittiming = esd_usb2_set_bittiming;
979 priv->can.do_set_mode = esd_usb2_set_mode;
980 priv->can.do_get_berr_counter = esd_usb2_get_berr_counter;
981 priv->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES;
982
983 netdev->flags |= IFF_ECHO; /* we support local echo */
984
985 netdev->netdev_ops = &esd_usb2_netdev_ops;
986
987 SET_NETDEV_DEV(netdev, &intf->dev);
988
989 err = register_candev(netdev);
990 if (err) {
991 dev_err(&intf->dev,
992 "couldn't register CAN device: %d\n", err);
993 free_candev(netdev);
994 err = -ENOMEM;
995 goto done;
996 }
997
998 dev->nets[index] = priv;
999 dev_info(netdev->dev.parent, "device %s registered\n", netdev->name);
1000
1001 done:
1002 return err;
1003 }
1004
1005 /*
1006 * probe function for new USB2 devices
1007 *
1008 * check version information and number of available
1009 * CAN interfaces
1010 */
esd_usb2_probe(struct usb_interface * intf,const struct usb_device_id * id)1011 static int esd_usb2_probe(struct usb_interface *intf,
1012 const struct usb_device_id *id)
1013 {
1014 struct esd_usb2 *dev;
1015 struct esd_usb2_msg msg;
1016 int i, err;
1017
1018 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1019 if (!dev) {
1020 err = -ENOMEM;
1021 goto done;
1022 }
1023
1024 dev->udev = interface_to_usbdev(intf);
1025
1026 init_usb_anchor(&dev->rx_submitted);
1027
1028 usb_set_intfdata(intf, dev);
1029
1030 /* query number of CAN interfaces (nets) */
1031 msg.msg.hdr.cmd = CMD_VERSION;
1032 msg.msg.hdr.len = 2;
1033 msg.msg.version.rsvd = 0;
1034 msg.msg.version.flags = 0;
1035 msg.msg.version.drv_version = 0;
1036
1037 err = esd_usb2_send_msg(dev, &msg);
1038 if (err < 0) {
1039 dev_err(&intf->dev, "sending version message failed\n");
1040 goto free_dev;
1041 }
1042
1043 err = esd_usb2_wait_msg(dev, &msg);
1044 if (err < 0) {
1045 dev_err(&intf->dev, "no version message answer\n");
1046 goto free_dev;
1047 }
1048
1049 dev->net_count = (int)msg.msg.version_reply.nets;
1050 dev->version = le32_to_cpu(msg.msg.version_reply.version);
1051
1052 if (device_create_file(&intf->dev, &dev_attr_firmware))
1053 dev_err(&intf->dev,
1054 "Couldn't create device file for firmware\n");
1055
1056 if (device_create_file(&intf->dev, &dev_attr_hardware))
1057 dev_err(&intf->dev,
1058 "Couldn't create device file for hardware\n");
1059
1060 if (device_create_file(&intf->dev, &dev_attr_nets))
1061 dev_err(&intf->dev,
1062 "Couldn't create device file for nets\n");
1063
1064 /* do per device probing */
1065 for (i = 0; i < dev->net_count; i++)
1066 esd_usb2_probe_one_net(intf, i);
1067
1068 return 0;
1069
1070 free_dev:
1071 kfree(dev);
1072 done:
1073 return err;
1074 }
1075
1076 /*
1077 * called by the usb core when the device is removed from the system
1078 */
esd_usb2_disconnect(struct usb_interface * intf)1079 static void esd_usb2_disconnect(struct usb_interface *intf)
1080 {
1081 struct esd_usb2 *dev = usb_get_intfdata(intf);
1082 struct net_device *netdev;
1083 int i;
1084
1085 device_remove_file(&intf->dev, &dev_attr_firmware);
1086 device_remove_file(&intf->dev, &dev_attr_hardware);
1087 device_remove_file(&intf->dev, &dev_attr_nets);
1088
1089 usb_set_intfdata(intf, NULL);
1090
1091 if (dev) {
1092 for (i = 0; i < dev->net_count; i++) {
1093 if (dev->nets[i]) {
1094 netdev = dev->nets[i]->netdev;
1095 unregister_netdev(netdev);
1096 free_candev(netdev);
1097 }
1098 }
1099 unlink_all_urbs(dev);
1100 }
1101 }
1102
1103 /* usb specific object needed to register this driver with the usb subsystem */
1104 static struct usb_driver esd_usb2_driver = {
1105 .name = "esd_usb2",
1106 .probe = esd_usb2_probe,
1107 .disconnect = esd_usb2_disconnect,
1108 .id_table = esd_usb2_table,
1109 };
1110
1111 module_usb_driver(esd_usb2_driver);
1112