1 /*
2 * CAN driver for esd CAN-USB/2 and CAN-USB/Micro
3 *
4 * Copyright (C) 2010-2012 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/signal.h>
20 #include <linux/slab.h>
21 #include <linux/module.h>
22 #include <linux/netdevice.h>
23 #include <linux/usb.h>
24
25 #include <linux/can.h>
26 #include <linux/can/dev.h>
27 #include <linux/can/error.h>
28
29 MODULE_AUTHOR("Matthias Fuchs <matthias.fuchs@esd.eu>");
30 MODULE_DESCRIPTION("CAN driver for esd CAN-USB/2 and CAN-USB/Micro interfaces");
31 MODULE_LICENSE("GPL v2");
32
33 /* Define these values to match your devices */
34 #define USB_ESDGMBH_VENDOR_ID 0x0ab4
35 #define USB_CANUSB2_PRODUCT_ID 0x0010
36 #define USB_CANUSBM_PRODUCT_ID 0x0011
37
38 #define ESD_USB2_CAN_CLOCK 60000000
39 #define ESD_USBM_CAN_CLOCK 36000000
40 #define ESD_USB2_MAX_NETS 2
41
42 /* USB2 commands */
43 #define CMD_VERSION 1 /* also used for VERSION_REPLY */
44 #define CMD_CAN_RX 2 /* device to host only */
45 #define CMD_CAN_TX 3 /* also used for TX_DONE */
46 #define CMD_SETBAUD 4 /* also used for SETBAUD_REPLY */
47 #define CMD_TS 5 /* also used for TS_REPLY */
48 #define CMD_IDADD 6 /* also used for IDADD_REPLY */
49
50 /* esd CAN message flags - dlc field */
51 #define ESD_RTR 0x10
52
53 /* esd CAN message flags - id field */
54 #define ESD_EXTID 0x20000000
55 #define ESD_EVENT 0x40000000
56 #define ESD_IDMASK 0x1fffffff
57
58 /* esd CAN event ids used by this driver */
59 #define ESD_EV_CAN_ERROR_EXT 2
60
61 /* baudrate message flags */
62 #define ESD_USB2_UBR 0x80000000
63 #define ESD_USB2_LOM 0x40000000
64 #define ESD_USB2_NO_BAUDRATE 0x7fffffff
65 #define ESD_USB2_TSEG1_MIN 1
66 #define ESD_USB2_TSEG1_MAX 16
67 #define ESD_USB2_TSEG1_SHIFT 16
68 #define ESD_USB2_TSEG2_MIN 1
69 #define ESD_USB2_TSEG2_MAX 8
70 #define ESD_USB2_TSEG2_SHIFT 20
71 #define ESD_USB2_SJW_MAX 4
72 #define ESD_USB2_SJW_SHIFT 14
73 #define ESD_USBM_SJW_SHIFT 24
74 #define ESD_USB2_BRP_MIN 1
75 #define ESD_USB2_BRP_MAX 1024
76 #define ESD_USB2_BRP_INC 1
77 #define ESD_USB2_3_SAMPLES 0x00800000
78
79 /* esd IDADD message */
80 #define ESD_ID_ENABLE 0x80
81 #define ESD_MAX_ID_SEGMENT 64
82
83 /* SJA1000 ECC register (emulated by usb2 firmware) */
84 #define SJA1000_ECC_SEG 0x1F
85 #define SJA1000_ECC_DIR 0x20
86 #define SJA1000_ECC_ERR 0x06
87 #define SJA1000_ECC_BIT 0x00
88 #define SJA1000_ECC_FORM 0x40
89 #define SJA1000_ECC_STUFF 0x80
90 #define SJA1000_ECC_MASK 0xc0
91
92 /* esd bus state event codes */
93 #define ESD_BUSSTATE_MASK 0xc0
94 #define ESD_BUSSTATE_WARN 0x40
95 #define ESD_BUSSTATE_ERRPASSIVE 0x80
96 #define ESD_BUSSTATE_BUSOFF 0xc0
97
98 #define RX_BUFFER_SIZE 1024
99 #define MAX_RX_URBS 4
100 #define MAX_TX_URBS 16 /* must be power of 2 */
101
102 struct header_msg {
103 u8 len; /* len is always the total message length in 32bit words */
104 u8 cmd;
105 u8 rsvd[2];
106 };
107
108 struct version_msg {
109 u8 len;
110 u8 cmd;
111 u8 rsvd;
112 u8 flags;
113 __le32 drv_version;
114 };
115
116 struct version_reply_msg {
117 u8 len;
118 u8 cmd;
119 u8 nets;
120 u8 features;
121 __le32 version;
122 u8 name[16];
123 __le32 rsvd;
124 __le32 ts;
125 };
126
127 struct rx_msg {
128 u8 len;
129 u8 cmd;
130 u8 net;
131 u8 dlc;
132 __le32 ts;
133 __le32 id; /* upper 3 bits contain flags */
134 u8 data[8];
135 };
136
137 struct tx_msg {
138 u8 len;
139 u8 cmd;
140 u8 net;
141 u8 dlc;
142 u32 hnd; /* opaque handle, not used by device */
143 __le32 id; /* upper 3 bits contain flags */
144 u8 data[8];
145 };
146
147 struct tx_done_msg {
148 u8 len;
149 u8 cmd;
150 u8 net;
151 u8 status;
152 u32 hnd; /* opaque handle, not used by device */
153 __le32 ts;
154 };
155
156 struct id_filter_msg {
157 u8 len;
158 u8 cmd;
159 u8 net;
160 u8 option;
161 __le32 mask[ESD_MAX_ID_SEGMENT + 1];
162 };
163
164 struct set_baudrate_msg {
165 u8 len;
166 u8 cmd;
167 u8 net;
168 u8 rsvd;
169 __le32 baud;
170 };
171
172 /* Main message type used between library and application */
173 struct __attribute__ ((packed)) esd_usb2_msg {
174 union {
175 struct header_msg hdr;
176 struct version_msg version;
177 struct version_reply_msg version_reply;
178 struct rx_msg rx;
179 struct tx_msg tx;
180 struct tx_done_msg txdone;
181 struct set_baudrate_msg setbaud;
182 struct id_filter_msg filter;
183 } msg;
184 };
185
186 static struct usb_device_id esd_usb2_table[] = {
187 {USB_DEVICE(USB_ESDGMBH_VENDOR_ID, USB_CANUSB2_PRODUCT_ID)},
188 {USB_DEVICE(USB_ESDGMBH_VENDOR_ID, USB_CANUSBM_PRODUCT_ID)},
189 {}
190 };
191 MODULE_DEVICE_TABLE(usb, esd_usb2_table);
192
193 struct esd_usb2_net_priv;
194
195 struct esd_tx_urb_context {
196 struct esd_usb2_net_priv *priv;
197 u32 echo_index;
198 int dlc;
199 };
200
201 struct esd_usb2 {
202 struct usb_device *udev;
203 struct esd_usb2_net_priv *nets[ESD_USB2_MAX_NETS];
204
205 struct usb_anchor rx_submitted;
206
207 int net_count;
208 u32 version;
209 int rxinitdone;
210 };
211
212 struct esd_usb2_net_priv {
213 struct can_priv can; /* must be the first member */
214
215 atomic_t active_tx_jobs;
216 struct usb_anchor tx_submitted;
217 struct esd_tx_urb_context tx_contexts[MAX_TX_URBS];
218
219 struct esd_usb2 *usb2;
220 struct net_device *netdev;
221 int index;
222 u8 old_state;
223 struct can_berr_counter bec;
224 };
225
esd_usb2_rx_event(struct esd_usb2_net_priv * priv,struct esd_usb2_msg * msg)226 static void esd_usb2_rx_event(struct esd_usb2_net_priv *priv,
227 struct esd_usb2_msg *msg)
228 {
229 struct net_device_stats *stats = &priv->netdev->stats;
230 struct can_frame *cf;
231 struct sk_buff *skb;
232 u32 id = le32_to_cpu(msg->msg.rx.id) & ESD_IDMASK;
233
234 if (id == ESD_EV_CAN_ERROR_EXT) {
235 u8 state = msg->msg.rx.data[0];
236 u8 ecc = msg->msg.rx.data[1];
237 u8 txerr = msg->msg.rx.data[2];
238 u8 rxerr = msg->msg.rx.data[3];
239
240 skb = alloc_can_err_skb(priv->netdev, &cf);
241 if (skb == NULL) {
242 stats->rx_dropped++;
243 return;
244 }
245
246 if (state != priv->old_state) {
247 priv->old_state = state;
248
249 switch (state & ESD_BUSSTATE_MASK) {
250 case ESD_BUSSTATE_BUSOFF:
251 priv->can.state = CAN_STATE_BUS_OFF;
252 cf->can_id |= CAN_ERR_BUSOFF;
253 priv->can.can_stats.bus_off++;
254 can_bus_off(priv->netdev);
255 break;
256 case ESD_BUSSTATE_WARN:
257 priv->can.state = CAN_STATE_ERROR_WARNING;
258 priv->can.can_stats.error_warning++;
259 break;
260 case ESD_BUSSTATE_ERRPASSIVE:
261 priv->can.state = CAN_STATE_ERROR_PASSIVE;
262 priv->can.can_stats.error_passive++;
263 break;
264 default:
265 priv->can.state = CAN_STATE_ERROR_ACTIVE;
266 break;
267 }
268 } else {
269 priv->can.can_stats.bus_error++;
270 stats->rx_errors++;
271
272 cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
273
274 switch (ecc & SJA1000_ECC_MASK) {
275 case SJA1000_ECC_BIT:
276 cf->data[2] |= CAN_ERR_PROT_BIT;
277 break;
278 case SJA1000_ECC_FORM:
279 cf->data[2] |= CAN_ERR_PROT_FORM;
280 break;
281 case SJA1000_ECC_STUFF:
282 cf->data[2] |= CAN_ERR_PROT_STUFF;
283 break;
284 default:
285 cf->data[3] = ecc & SJA1000_ECC_SEG;
286 break;
287 }
288
289 /* Error occurred during transmission? */
290 if (!(ecc & SJA1000_ECC_DIR))
291 cf->data[2] |= CAN_ERR_PROT_TX;
292
293 if (priv->can.state == CAN_STATE_ERROR_WARNING ||
294 priv->can.state == CAN_STATE_ERROR_PASSIVE) {
295 cf->data[1] = (txerr > rxerr) ?
296 CAN_ERR_CRTL_TX_PASSIVE :
297 CAN_ERR_CRTL_RX_PASSIVE;
298 }
299 cf->data[6] = txerr;
300 cf->data[7] = rxerr;
301 }
302
303 priv->bec.txerr = txerr;
304 priv->bec.rxerr = rxerr;
305
306 stats->rx_packets++;
307 stats->rx_bytes += cf->can_dlc;
308 netif_rx(skb);
309 }
310 }
311
esd_usb2_rx_can_msg(struct esd_usb2_net_priv * priv,struct esd_usb2_msg * msg)312 static void esd_usb2_rx_can_msg(struct esd_usb2_net_priv *priv,
313 struct esd_usb2_msg *msg)
314 {
315 struct net_device_stats *stats = &priv->netdev->stats;
316 struct can_frame *cf;
317 struct sk_buff *skb;
318 int i;
319 u32 id;
320
321 if (!netif_device_present(priv->netdev))
322 return;
323
324 id = le32_to_cpu(msg->msg.rx.id);
325
326 if (id & ESD_EVENT) {
327 esd_usb2_rx_event(priv, msg);
328 } else {
329 skb = alloc_can_skb(priv->netdev, &cf);
330 if (skb == NULL) {
331 stats->rx_dropped++;
332 return;
333 }
334
335 cf->can_id = id & ESD_IDMASK;
336 cf->can_dlc = get_can_dlc(msg->msg.rx.dlc);
337
338 if (id & ESD_EXTID)
339 cf->can_id |= CAN_EFF_FLAG;
340
341 if (msg->msg.rx.dlc & ESD_RTR) {
342 cf->can_id |= CAN_RTR_FLAG;
343 } else {
344 for (i = 0; i < cf->can_dlc; i++)
345 cf->data[i] = msg->msg.rx.data[i];
346 }
347
348 stats->rx_packets++;
349 stats->rx_bytes += cf->can_dlc;
350 netif_rx(skb);
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 if (msg->msg.rx.net >= dev->net_count) {
413 dev_err(dev->udev->dev.parent, "format error\n");
414 break;
415 }
416
417 esd_usb2_rx_can_msg(dev->nets[msg->msg.rx.net], msg);
418 break;
419
420 case CMD_CAN_TX:
421 if (msg->msg.txdone.net >= dev->net_count) {
422 dev_err(dev->udev->dev.parent, "format error\n");
423 break;
424 }
425
426 esd_usb2_tx_done_msg(dev->nets[msg->msg.txdone.net],
427 msg);
428 break;
429 }
430
431 pos += msg->msg.hdr.len << 2;
432
433 if (pos > urb->actual_length) {
434 dev_err(dev->udev->dev.parent, "format error\n");
435 break;
436 }
437 }
438
439 resubmit_urb:
440 usb_fill_bulk_urb(urb, dev->udev, usb_rcvbulkpipe(dev->udev, 1),
441 urb->transfer_buffer, RX_BUFFER_SIZE,
442 esd_usb2_read_bulk_callback, dev);
443
444 retval = usb_submit_urb(urb, GFP_ATOMIC);
445 if (retval == -ENODEV) {
446 for (i = 0; i < dev->net_count; i++) {
447 if (dev->nets[i])
448 netif_device_detach(dev->nets[i]->netdev);
449 }
450 } else if (retval) {
451 dev_err(dev->udev->dev.parent,
452 "failed resubmitting read bulk urb: %d\n", retval);
453 }
454
455 return;
456 }
457
458 /*
459 * callback for bulk IN urb
460 */
esd_usb2_write_bulk_callback(struct urb * urb)461 static void esd_usb2_write_bulk_callback(struct urb *urb)
462 {
463 struct esd_tx_urb_context *context = urb->context;
464 struct esd_usb2_net_priv *priv;
465 struct net_device *netdev;
466 size_t size = sizeof(struct esd_usb2_msg);
467
468 WARN_ON(!context);
469
470 priv = context->priv;
471 netdev = priv->netdev;
472
473 /* free up our allocated buffer */
474 usb_free_coherent(urb->dev, size,
475 urb->transfer_buffer, urb->transfer_dma);
476
477 if (!netif_device_present(netdev))
478 return;
479
480 if (urb->status)
481 netdev_info(netdev, "Tx URB aborted (%d)\n", urb->status);
482
483 netdev->trans_start = jiffies;
484 }
485
show_firmware(struct device * d,struct device_attribute * attr,char * buf)486 static ssize_t show_firmware(struct device *d,
487 struct device_attribute *attr, char *buf)
488 {
489 struct usb_interface *intf = to_usb_interface(d);
490 struct esd_usb2 *dev = usb_get_intfdata(intf);
491
492 return sprintf(buf, "%d.%d.%d\n",
493 (dev->version >> 12) & 0xf,
494 (dev->version >> 8) & 0xf,
495 dev->version & 0xff);
496 }
497 static DEVICE_ATTR(firmware, S_IRUGO, show_firmware, NULL);
498
show_hardware(struct device * d,struct device_attribute * attr,char * buf)499 static ssize_t show_hardware(struct device *d,
500 struct device_attribute *attr, char *buf)
501 {
502 struct usb_interface *intf = to_usb_interface(d);
503 struct esd_usb2 *dev = usb_get_intfdata(intf);
504
505 return sprintf(buf, "%d.%d.%d\n",
506 (dev->version >> 28) & 0xf,
507 (dev->version >> 24) & 0xf,
508 (dev->version >> 16) & 0xff);
509 }
510 static DEVICE_ATTR(hardware, S_IRUGO, show_hardware, NULL);
511
show_nets(struct device * d,struct device_attribute * attr,char * buf)512 static ssize_t show_nets(struct device *d,
513 struct device_attribute *attr, char *buf)
514 {
515 struct usb_interface *intf = to_usb_interface(d);
516 struct esd_usb2 *dev = usb_get_intfdata(intf);
517
518 return sprintf(buf, "%d", dev->net_count);
519 }
520 static DEVICE_ATTR(nets, S_IRUGO, show_nets, NULL);
521
esd_usb2_send_msg(struct esd_usb2 * dev,struct esd_usb2_msg * msg)522 static int esd_usb2_send_msg(struct esd_usb2 *dev, struct esd_usb2_msg *msg)
523 {
524 int actual_length;
525
526 return usb_bulk_msg(dev->udev,
527 usb_sndbulkpipe(dev->udev, 2),
528 msg,
529 msg->msg.hdr.len << 2,
530 &actual_length,
531 1000);
532 }
533
esd_usb2_wait_msg(struct esd_usb2 * dev,struct esd_usb2_msg * msg)534 static int esd_usb2_wait_msg(struct esd_usb2 *dev,
535 struct esd_usb2_msg *msg)
536 {
537 int actual_length;
538
539 return usb_bulk_msg(dev->udev,
540 usb_rcvbulkpipe(dev->udev, 1),
541 msg,
542 sizeof(*msg),
543 &actual_length,
544 1000);
545 }
546
esd_usb2_setup_rx_urbs(struct esd_usb2 * dev)547 static int esd_usb2_setup_rx_urbs(struct esd_usb2 *dev)
548 {
549 int i, err = 0;
550
551 if (dev->rxinitdone)
552 return 0;
553
554 for (i = 0; i < MAX_RX_URBS; i++) {
555 struct urb *urb = NULL;
556 u8 *buf = NULL;
557
558 /* create a URB, and a buffer for it */
559 urb = usb_alloc_urb(0, GFP_KERNEL);
560 if (!urb) {
561 dev_warn(dev->udev->dev.parent,
562 "No memory left for URBs\n");
563 err = -ENOMEM;
564 break;
565 }
566
567 buf = usb_alloc_coherent(dev->udev, RX_BUFFER_SIZE, GFP_KERNEL,
568 &urb->transfer_dma);
569 if (!buf) {
570 dev_warn(dev->udev->dev.parent,
571 "No memory left for USB buffer\n");
572 err = -ENOMEM;
573 goto freeurb;
574 }
575
576 usb_fill_bulk_urb(urb, dev->udev,
577 usb_rcvbulkpipe(dev->udev, 1),
578 buf, RX_BUFFER_SIZE,
579 esd_usb2_read_bulk_callback, dev);
580 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
581 usb_anchor_urb(urb, &dev->rx_submitted);
582
583 err = usb_submit_urb(urb, GFP_KERNEL);
584 if (err) {
585 usb_unanchor_urb(urb);
586 usb_free_coherent(dev->udev, RX_BUFFER_SIZE, buf,
587 urb->transfer_dma);
588 }
589
590 freeurb:
591 /* Drop reference, USB core will take care of freeing it */
592 usb_free_urb(urb);
593 if (err)
594 break;
595 }
596
597 /* Did we submit any URBs */
598 if (i == 0) {
599 dev_err(dev->udev->dev.parent, "couldn't setup read URBs\n");
600 return err;
601 }
602
603 /* Warn if we've couldn't transmit all the URBs */
604 if (i < MAX_RX_URBS) {
605 dev_warn(dev->udev->dev.parent,
606 "rx performance may be slow\n");
607 }
608
609 dev->rxinitdone = 1;
610 return 0;
611 }
612
613 /*
614 * Start interface
615 */
esd_usb2_start(struct esd_usb2_net_priv * priv)616 static int esd_usb2_start(struct esd_usb2_net_priv *priv)
617 {
618 struct esd_usb2 *dev = priv->usb2;
619 struct net_device *netdev = priv->netdev;
620 struct esd_usb2_msg *msg;
621 int err, i;
622
623 msg = kmalloc(sizeof(*msg), GFP_KERNEL);
624 if (!msg) {
625 err = -ENOMEM;
626 goto out;
627 }
628
629 /*
630 * Enable all IDs
631 * The IDADD message takes up to 64 32 bit bitmasks (2048 bits).
632 * Each bit represents one 11 bit CAN identifier. A set bit
633 * enables reception of the corresponding CAN identifier. A cleared
634 * bit disabled this identifier. An additional bitmask value
635 * following the CAN 2.0A bits is used to enable reception of
636 * extended CAN frames. Only the LSB of this final mask is checked
637 * for the complete 29 bit ID range. The IDADD message also allows
638 * filter configuration for an ID subset. In this case you can add
639 * the number of the starting bitmask (0..64) to the filter.option
640 * field followed by only some bitmasks.
641 */
642 msg->msg.hdr.cmd = CMD_IDADD;
643 msg->msg.hdr.len = 2 + ESD_MAX_ID_SEGMENT;
644 msg->msg.filter.net = priv->index;
645 msg->msg.filter.option = ESD_ID_ENABLE; /* start with segment 0 */
646 for (i = 0; i < ESD_MAX_ID_SEGMENT; i++)
647 msg->msg.filter.mask[i] = cpu_to_le32(0xffffffff);
648 /* enable 29bit extended IDs */
649 msg->msg.filter.mask[ESD_MAX_ID_SEGMENT] = cpu_to_le32(0x00000001);
650
651 err = esd_usb2_send_msg(dev, msg);
652 if (err)
653 goto out;
654
655 err = esd_usb2_setup_rx_urbs(dev);
656 if (err)
657 goto out;
658
659 priv->can.state = CAN_STATE_ERROR_ACTIVE;
660
661 out:
662 if (err == -ENODEV)
663 netif_device_detach(netdev);
664 if (err)
665 netdev_err(netdev, "couldn't start device: %d\n", err);
666
667 kfree(msg);
668 return err;
669 }
670
unlink_all_urbs(struct esd_usb2 * dev)671 static void unlink_all_urbs(struct esd_usb2 *dev)
672 {
673 struct esd_usb2_net_priv *priv;
674 int i, j;
675
676 usb_kill_anchored_urbs(&dev->rx_submitted);
677 for (i = 0; i < dev->net_count; i++) {
678 priv = dev->nets[i];
679 if (priv) {
680 usb_kill_anchored_urbs(&priv->tx_submitted);
681 atomic_set(&priv->active_tx_jobs, 0);
682
683 for (j = 0; j < MAX_TX_URBS; j++)
684 priv->tx_contexts[j].echo_index = MAX_TX_URBS;
685 }
686 }
687 }
688
esd_usb2_open(struct net_device * netdev)689 static int esd_usb2_open(struct net_device *netdev)
690 {
691 struct esd_usb2_net_priv *priv = netdev_priv(netdev);
692 int err;
693
694 /* common open */
695 err = open_candev(netdev);
696 if (err)
697 return err;
698
699 /* finally start device */
700 err = esd_usb2_start(priv);
701 if (err) {
702 netdev_warn(netdev, "couldn't start device: %d\n", err);
703 close_candev(netdev);
704 return err;
705 }
706
707 netif_start_queue(netdev);
708
709 return 0;
710 }
711
esd_usb2_start_xmit(struct sk_buff * skb,struct net_device * netdev)712 static netdev_tx_t esd_usb2_start_xmit(struct sk_buff *skb,
713 struct net_device *netdev)
714 {
715 struct esd_usb2_net_priv *priv = netdev_priv(netdev);
716 struct esd_usb2 *dev = priv->usb2;
717 struct esd_tx_urb_context *context = NULL;
718 struct net_device_stats *stats = &netdev->stats;
719 struct can_frame *cf = (struct can_frame *)skb->data;
720 struct esd_usb2_msg *msg;
721 struct urb *urb;
722 u8 *buf;
723 int i, err;
724 int ret = NETDEV_TX_OK;
725 size_t size = sizeof(struct esd_usb2_msg);
726
727 if (can_dropped_invalid_skb(netdev, skb))
728 return NETDEV_TX_OK;
729
730 /* create a URB, and a buffer for it, and copy the data to the URB */
731 urb = usb_alloc_urb(0, GFP_ATOMIC);
732 if (!urb) {
733 netdev_err(netdev, "No memory left for URBs\n");
734 stats->tx_dropped++;
735 dev_kfree_skb(skb);
736 goto nourbmem;
737 }
738
739 buf = usb_alloc_coherent(dev->udev, size, GFP_ATOMIC,
740 &urb->transfer_dma);
741 if (!buf) {
742 netdev_err(netdev, "No memory left for USB buffer\n");
743 stats->tx_dropped++;
744 dev_kfree_skb(skb);
745 goto nobufmem;
746 }
747
748 msg = (struct esd_usb2_msg *)buf;
749
750 msg->msg.hdr.len = 3; /* minimal length */
751 msg->msg.hdr.cmd = CMD_CAN_TX;
752 msg->msg.tx.net = priv->index;
753 msg->msg.tx.dlc = cf->can_dlc;
754 msg->msg.tx.id = cpu_to_le32(cf->can_id & CAN_ERR_MASK);
755
756 if (cf->can_id & CAN_RTR_FLAG)
757 msg->msg.tx.dlc |= ESD_RTR;
758
759 if (cf->can_id & CAN_EFF_FLAG)
760 msg->msg.tx.id |= cpu_to_le32(ESD_EXTID);
761
762 for (i = 0; i < cf->can_dlc; i++)
763 msg->msg.tx.data[i] = cf->data[i];
764
765 msg->msg.hdr.len += (cf->can_dlc + 3) >> 2;
766
767 for (i = 0; i < MAX_TX_URBS; i++) {
768 if (priv->tx_contexts[i].echo_index == MAX_TX_URBS) {
769 context = &priv->tx_contexts[i];
770 break;
771 }
772 }
773
774 /*
775 * This may never happen.
776 */
777 if (!context) {
778 netdev_warn(netdev, "couldn't find free context\n");
779 ret = NETDEV_TX_BUSY;
780 goto releasebuf;
781 }
782
783 context->priv = priv;
784 context->echo_index = i;
785 context->dlc = cf->can_dlc;
786
787 /* hnd must not be 0 - MSB is stripped in txdone handling */
788 msg->msg.tx.hnd = 0x80000000 | i; /* returned in TX done message */
789
790 usb_fill_bulk_urb(urb, dev->udev, usb_sndbulkpipe(dev->udev, 2), buf,
791 msg->msg.hdr.len << 2,
792 esd_usb2_write_bulk_callback, context);
793
794 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
795
796 usb_anchor_urb(urb, &priv->tx_submitted);
797
798 can_put_echo_skb(skb, netdev, context->echo_index);
799
800 atomic_inc(&priv->active_tx_jobs);
801
802 /* Slow down tx path */
803 if (atomic_read(&priv->active_tx_jobs) >= MAX_TX_URBS)
804 netif_stop_queue(netdev);
805
806 err = usb_submit_urb(urb, GFP_ATOMIC);
807 if (err) {
808 can_free_echo_skb(netdev, context->echo_index);
809
810 atomic_dec(&priv->active_tx_jobs);
811 usb_unanchor_urb(urb);
812
813 stats->tx_dropped++;
814
815 if (err == -ENODEV)
816 netif_device_detach(netdev);
817 else
818 netdev_warn(netdev, "failed tx_urb %d\n", err);
819
820 goto releasebuf;
821 }
822
823 netdev->trans_start = jiffies;
824
825 /*
826 * Release our reference to this URB, the USB core will eventually free
827 * it entirely.
828 */
829 usb_free_urb(urb);
830
831 return NETDEV_TX_OK;
832
833 releasebuf:
834 usb_free_coherent(dev->udev, size, buf, urb->transfer_dma);
835
836 nobufmem:
837 usb_free_urb(urb);
838
839 nourbmem:
840 return ret;
841 }
842
esd_usb2_close(struct net_device * netdev)843 static int esd_usb2_close(struct net_device *netdev)
844 {
845 struct esd_usb2_net_priv *priv = netdev_priv(netdev);
846 struct esd_usb2_msg *msg;
847 int i;
848
849 msg = kmalloc(sizeof(*msg), GFP_KERNEL);
850 if (!msg)
851 return -ENOMEM;
852
853 /* Disable all IDs (see esd_usb2_start()) */
854 msg->msg.hdr.cmd = CMD_IDADD;
855 msg->msg.hdr.len = 2 + ESD_MAX_ID_SEGMENT;
856 msg->msg.filter.net = priv->index;
857 msg->msg.filter.option = ESD_ID_ENABLE; /* start with segment 0 */
858 for (i = 0; i <= ESD_MAX_ID_SEGMENT; i++)
859 msg->msg.filter.mask[i] = 0;
860 if (esd_usb2_send_msg(priv->usb2, msg) < 0)
861 netdev_err(netdev, "sending idadd message failed\n");
862
863 /* set CAN controller to reset mode */
864 msg->msg.hdr.len = 2;
865 msg->msg.hdr.cmd = CMD_SETBAUD;
866 msg->msg.setbaud.net = priv->index;
867 msg->msg.setbaud.rsvd = 0;
868 msg->msg.setbaud.baud = cpu_to_le32(ESD_USB2_NO_BAUDRATE);
869 if (esd_usb2_send_msg(priv->usb2, msg) < 0)
870 netdev_err(netdev, "sending setbaud message failed\n");
871
872 priv->can.state = CAN_STATE_STOPPED;
873
874 netif_stop_queue(netdev);
875
876 close_candev(netdev);
877
878 kfree(msg);
879
880 return 0;
881 }
882
883 static const struct net_device_ops esd_usb2_netdev_ops = {
884 .ndo_open = esd_usb2_open,
885 .ndo_stop = esd_usb2_close,
886 .ndo_start_xmit = esd_usb2_start_xmit,
887 .ndo_change_mtu = can_change_mtu,
888 };
889
890 static const struct can_bittiming_const esd_usb2_bittiming_const = {
891 .name = "esd_usb2",
892 .tseg1_min = ESD_USB2_TSEG1_MIN,
893 .tseg1_max = ESD_USB2_TSEG1_MAX,
894 .tseg2_min = ESD_USB2_TSEG2_MIN,
895 .tseg2_max = ESD_USB2_TSEG2_MAX,
896 .sjw_max = ESD_USB2_SJW_MAX,
897 .brp_min = ESD_USB2_BRP_MIN,
898 .brp_max = ESD_USB2_BRP_MAX,
899 .brp_inc = ESD_USB2_BRP_INC,
900 };
901
esd_usb2_set_bittiming(struct net_device * netdev)902 static int esd_usb2_set_bittiming(struct net_device *netdev)
903 {
904 struct esd_usb2_net_priv *priv = netdev_priv(netdev);
905 struct can_bittiming *bt = &priv->can.bittiming;
906 struct esd_usb2_msg *msg;
907 int err;
908 u32 canbtr;
909 int sjw_shift;
910
911 canbtr = ESD_USB2_UBR;
912 if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
913 canbtr |= ESD_USB2_LOM;
914
915 canbtr |= (bt->brp - 1) & (ESD_USB2_BRP_MAX - 1);
916
917 if (le16_to_cpu(priv->usb2->udev->descriptor.idProduct) ==
918 USB_CANUSBM_PRODUCT_ID)
919 sjw_shift = ESD_USBM_SJW_SHIFT;
920 else
921 sjw_shift = ESD_USB2_SJW_SHIFT;
922
923 canbtr |= ((bt->sjw - 1) & (ESD_USB2_SJW_MAX - 1))
924 << sjw_shift;
925 canbtr |= ((bt->prop_seg + bt->phase_seg1 - 1)
926 & (ESD_USB2_TSEG1_MAX - 1))
927 << ESD_USB2_TSEG1_SHIFT;
928 canbtr |= ((bt->phase_seg2 - 1) & (ESD_USB2_TSEG2_MAX - 1))
929 << ESD_USB2_TSEG2_SHIFT;
930 if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
931 canbtr |= ESD_USB2_3_SAMPLES;
932
933 msg = kmalloc(sizeof(*msg), GFP_KERNEL);
934 if (!msg)
935 return -ENOMEM;
936
937 msg->msg.hdr.len = 2;
938 msg->msg.hdr.cmd = CMD_SETBAUD;
939 msg->msg.setbaud.net = priv->index;
940 msg->msg.setbaud.rsvd = 0;
941 msg->msg.setbaud.baud = cpu_to_le32(canbtr);
942
943 netdev_info(netdev, "setting BTR=%#x\n", canbtr);
944
945 err = esd_usb2_send_msg(priv->usb2, msg);
946
947 kfree(msg);
948 return err;
949 }
950
esd_usb2_get_berr_counter(const struct net_device * netdev,struct can_berr_counter * bec)951 static int esd_usb2_get_berr_counter(const struct net_device *netdev,
952 struct can_berr_counter *bec)
953 {
954 struct esd_usb2_net_priv *priv = netdev_priv(netdev);
955
956 bec->txerr = priv->bec.txerr;
957 bec->rxerr = priv->bec.rxerr;
958
959 return 0;
960 }
961
esd_usb2_set_mode(struct net_device * netdev,enum can_mode mode)962 static int esd_usb2_set_mode(struct net_device *netdev, enum can_mode mode)
963 {
964 switch (mode) {
965 case CAN_MODE_START:
966 netif_wake_queue(netdev);
967 break;
968
969 default:
970 return -EOPNOTSUPP;
971 }
972
973 return 0;
974 }
975
esd_usb2_probe_one_net(struct usb_interface * intf,int index)976 static int esd_usb2_probe_one_net(struct usb_interface *intf, int index)
977 {
978 struct esd_usb2 *dev = usb_get_intfdata(intf);
979 struct net_device *netdev;
980 struct esd_usb2_net_priv *priv;
981 int err = 0;
982 int i;
983
984 netdev = alloc_candev(sizeof(*priv), MAX_TX_URBS);
985 if (!netdev) {
986 dev_err(&intf->dev, "couldn't alloc candev\n");
987 err = -ENOMEM;
988 goto done;
989 }
990
991 priv = netdev_priv(netdev);
992
993 init_usb_anchor(&priv->tx_submitted);
994 atomic_set(&priv->active_tx_jobs, 0);
995
996 for (i = 0; i < MAX_TX_URBS; i++)
997 priv->tx_contexts[i].echo_index = MAX_TX_URBS;
998
999 priv->usb2 = dev;
1000 priv->netdev = netdev;
1001 priv->index = index;
1002
1003 priv->can.state = CAN_STATE_STOPPED;
1004 priv->can.ctrlmode_supported = CAN_CTRLMODE_LISTENONLY;
1005
1006 if (le16_to_cpu(dev->udev->descriptor.idProduct) ==
1007 USB_CANUSBM_PRODUCT_ID)
1008 priv->can.clock.freq = ESD_USBM_CAN_CLOCK;
1009 else {
1010 priv->can.clock.freq = ESD_USB2_CAN_CLOCK;
1011 priv->can.ctrlmode_supported |= CAN_CTRLMODE_3_SAMPLES;
1012 }
1013
1014 priv->can.bittiming_const = &esd_usb2_bittiming_const;
1015 priv->can.do_set_bittiming = esd_usb2_set_bittiming;
1016 priv->can.do_set_mode = esd_usb2_set_mode;
1017 priv->can.do_get_berr_counter = esd_usb2_get_berr_counter;
1018
1019 netdev->flags |= IFF_ECHO; /* we support local echo */
1020
1021 netdev->netdev_ops = &esd_usb2_netdev_ops;
1022
1023 SET_NETDEV_DEV(netdev, &intf->dev);
1024 netdev->dev_id = index;
1025
1026 err = register_candev(netdev);
1027 if (err) {
1028 dev_err(&intf->dev, "couldn't register CAN device: %d\n", err);
1029 free_candev(netdev);
1030 err = -ENOMEM;
1031 goto done;
1032 }
1033
1034 dev->nets[index] = priv;
1035 netdev_info(netdev, "device %s registered\n", netdev->name);
1036
1037 done:
1038 return err;
1039 }
1040
1041 /*
1042 * probe function for new USB2 devices
1043 *
1044 * check version information and number of available
1045 * CAN interfaces
1046 */
esd_usb2_probe(struct usb_interface * intf,const struct usb_device_id * id)1047 static int esd_usb2_probe(struct usb_interface *intf,
1048 const struct usb_device_id *id)
1049 {
1050 struct esd_usb2 *dev;
1051 struct esd_usb2_msg *msg;
1052 int i, err;
1053
1054 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1055 if (!dev) {
1056 err = -ENOMEM;
1057 goto done;
1058 }
1059
1060 dev->udev = interface_to_usbdev(intf);
1061
1062 init_usb_anchor(&dev->rx_submitted);
1063
1064 usb_set_intfdata(intf, dev);
1065
1066 msg = kmalloc(sizeof(*msg), GFP_KERNEL);
1067 if (!msg) {
1068 err = -ENOMEM;
1069 goto free_msg;
1070 }
1071
1072 /* query number of CAN interfaces (nets) */
1073 msg->msg.hdr.cmd = CMD_VERSION;
1074 msg->msg.hdr.len = 2;
1075 msg->msg.version.rsvd = 0;
1076 msg->msg.version.flags = 0;
1077 msg->msg.version.drv_version = 0;
1078
1079 err = esd_usb2_send_msg(dev, msg);
1080 if (err < 0) {
1081 dev_err(&intf->dev, "sending version message failed\n");
1082 goto free_msg;
1083 }
1084
1085 err = esd_usb2_wait_msg(dev, msg);
1086 if (err < 0) {
1087 dev_err(&intf->dev, "no version message answer\n");
1088 goto free_msg;
1089 }
1090
1091 dev->net_count = (int)msg->msg.version_reply.nets;
1092 dev->version = le32_to_cpu(msg->msg.version_reply.version);
1093
1094 if (device_create_file(&intf->dev, &dev_attr_firmware))
1095 dev_err(&intf->dev,
1096 "Couldn't create device file for firmware\n");
1097
1098 if (device_create_file(&intf->dev, &dev_attr_hardware))
1099 dev_err(&intf->dev,
1100 "Couldn't create device file for hardware\n");
1101
1102 if (device_create_file(&intf->dev, &dev_attr_nets))
1103 dev_err(&intf->dev,
1104 "Couldn't create device file for nets\n");
1105
1106 /* do per device probing */
1107 for (i = 0; i < dev->net_count; i++)
1108 esd_usb2_probe_one_net(intf, i);
1109
1110 free_msg:
1111 kfree(msg);
1112 if (err)
1113 kfree(dev);
1114 done:
1115 return err;
1116 }
1117
1118 /*
1119 * called by the usb core when the device is removed from the system
1120 */
esd_usb2_disconnect(struct usb_interface * intf)1121 static void esd_usb2_disconnect(struct usb_interface *intf)
1122 {
1123 struct esd_usb2 *dev = usb_get_intfdata(intf);
1124 struct net_device *netdev;
1125 int i;
1126
1127 device_remove_file(&intf->dev, &dev_attr_firmware);
1128 device_remove_file(&intf->dev, &dev_attr_hardware);
1129 device_remove_file(&intf->dev, &dev_attr_nets);
1130
1131 usb_set_intfdata(intf, NULL);
1132
1133 if (dev) {
1134 for (i = 0; i < dev->net_count; i++) {
1135 if (dev->nets[i]) {
1136 netdev = dev->nets[i]->netdev;
1137 unregister_netdev(netdev);
1138 free_candev(netdev);
1139 }
1140 }
1141 unlink_all_urbs(dev);
1142 kfree(dev);
1143 }
1144 }
1145
1146 /* usb specific object needed to register this driver with the usb subsystem */
1147 static struct usb_driver esd_usb2_driver = {
1148 .name = "esd_usb2",
1149 .probe = esd_usb2_probe,
1150 .disconnect = esd_usb2_disconnect,
1151 .id_table = esd_usb2_table,
1152 };
1153
1154 module_usb_driver(esd_usb2_driver);
1155