1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * CAN driver for esd CAN-USB/2 and CAN-USB/Micro
4 *
5 * Copyright (C) 2010-2012 Matthias Fuchs <matthias.fuchs@esd.eu>, esd gmbh
6 */
7 #include <linux/signal.h>
8 #include <linux/slab.h>
9 #include <linux/module.h>
10 #include <linux/netdevice.h>
11 #include <linux/usb.h>
12
13 #include <linux/can.h>
14 #include <linux/can/dev.h>
15 #include <linux/can/error.h>
16
17 MODULE_AUTHOR("Matthias Fuchs <matthias.fuchs@esd.eu>");
18 MODULE_DESCRIPTION("CAN driver for esd CAN-USB/2 and CAN-USB/Micro interfaces");
19 MODULE_LICENSE("GPL v2");
20
21 /* Define these values to match your devices */
22 #define USB_ESDGMBH_VENDOR_ID 0x0ab4
23 #define USB_CANUSB2_PRODUCT_ID 0x0010
24 #define USB_CANUSBM_PRODUCT_ID 0x0011
25
26 #define ESD_USB2_CAN_CLOCK 60000000
27 #define ESD_USBM_CAN_CLOCK 36000000
28 #define ESD_USB2_MAX_NETS 2
29
30 /* USB2 commands */
31 #define CMD_VERSION 1 /* also used for VERSION_REPLY */
32 #define CMD_CAN_RX 2 /* device to host only */
33 #define CMD_CAN_TX 3 /* also used for TX_DONE */
34 #define CMD_SETBAUD 4 /* also used for SETBAUD_REPLY */
35 #define CMD_TS 5 /* also used for TS_REPLY */
36 #define CMD_IDADD 6 /* also used for IDADD_REPLY */
37
38 /* esd CAN message flags - dlc field */
39 #define ESD_RTR 0x10
40
41 /* esd CAN message flags - id field */
42 #define ESD_EXTID 0x20000000
43 #define ESD_EVENT 0x40000000
44 #define ESD_IDMASK 0x1fffffff
45
46 /* esd CAN event ids used by this driver */
47 #define ESD_EV_CAN_ERROR_EXT 2
48
49 /* baudrate message flags */
50 #define ESD_USB2_UBR 0x80000000
51 #define ESD_USB2_LOM 0x40000000
52 #define ESD_USB2_NO_BAUDRATE 0x7fffffff
53 #define ESD_USB2_TSEG1_MIN 1
54 #define ESD_USB2_TSEG1_MAX 16
55 #define ESD_USB2_TSEG1_SHIFT 16
56 #define ESD_USB2_TSEG2_MIN 1
57 #define ESD_USB2_TSEG2_MAX 8
58 #define ESD_USB2_TSEG2_SHIFT 20
59 #define ESD_USB2_SJW_MAX 4
60 #define ESD_USB2_SJW_SHIFT 14
61 #define ESD_USBM_SJW_SHIFT 24
62 #define ESD_USB2_BRP_MIN 1
63 #define ESD_USB2_BRP_MAX 1024
64 #define ESD_USB2_BRP_INC 1
65 #define ESD_USB2_3_SAMPLES 0x00800000
66
67 /* esd IDADD message */
68 #define ESD_ID_ENABLE 0x80
69 #define ESD_MAX_ID_SEGMENT 64
70
71 /* SJA1000 ECC register (emulated by usb2 firmware) */
72 #define SJA1000_ECC_SEG 0x1F
73 #define SJA1000_ECC_DIR 0x20
74 #define SJA1000_ECC_ERR 0x06
75 #define SJA1000_ECC_BIT 0x00
76 #define SJA1000_ECC_FORM 0x40
77 #define SJA1000_ECC_STUFF 0x80
78 #define SJA1000_ECC_MASK 0xc0
79
80 /* esd bus state event codes */
81 #define ESD_BUSSTATE_MASK 0xc0
82 #define ESD_BUSSTATE_WARN 0x40
83 #define ESD_BUSSTATE_ERRPASSIVE 0x80
84 #define ESD_BUSSTATE_BUSOFF 0xc0
85
86 #define RX_BUFFER_SIZE 1024
87 #define MAX_RX_URBS 4
88 #define MAX_TX_URBS 16 /* must be power of 2 */
89
90 struct header_msg {
91 u8 len; /* len is always the total message length in 32bit words */
92 u8 cmd;
93 u8 rsvd[2];
94 };
95
96 struct version_msg {
97 u8 len;
98 u8 cmd;
99 u8 rsvd;
100 u8 flags;
101 __le32 drv_version;
102 };
103
104 struct version_reply_msg {
105 u8 len;
106 u8 cmd;
107 u8 nets;
108 u8 features;
109 __le32 version;
110 u8 name[16];
111 __le32 rsvd;
112 __le32 ts;
113 };
114
115 struct rx_msg {
116 u8 len;
117 u8 cmd;
118 u8 net;
119 u8 dlc;
120 __le32 ts;
121 __le32 id; /* upper 3 bits contain flags */
122 u8 data[8];
123 };
124
125 struct tx_msg {
126 u8 len;
127 u8 cmd;
128 u8 net;
129 u8 dlc;
130 u32 hnd; /* opaque handle, not used by device */
131 __le32 id; /* upper 3 bits contain flags */
132 u8 data[8];
133 };
134
135 struct tx_done_msg {
136 u8 len;
137 u8 cmd;
138 u8 net;
139 u8 status;
140 u32 hnd; /* opaque handle, not used by device */
141 __le32 ts;
142 };
143
144 struct id_filter_msg {
145 u8 len;
146 u8 cmd;
147 u8 net;
148 u8 option;
149 __le32 mask[ESD_MAX_ID_SEGMENT + 1];
150 };
151
152 struct set_baudrate_msg {
153 u8 len;
154 u8 cmd;
155 u8 net;
156 u8 rsvd;
157 __le32 baud;
158 };
159
160 /* Main message type used between library and application */
161 struct __attribute__ ((packed)) esd_usb2_msg {
162 union {
163 struct header_msg hdr;
164 struct version_msg version;
165 struct version_reply_msg version_reply;
166 struct rx_msg rx;
167 struct tx_msg tx;
168 struct tx_done_msg txdone;
169 struct set_baudrate_msg setbaud;
170 struct id_filter_msg filter;
171 } msg;
172 };
173
174 static struct usb_device_id esd_usb2_table[] = {
175 {USB_DEVICE(USB_ESDGMBH_VENDOR_ID, USB_CANUSB2_PRODUCT_ID)},
176 {USB_DEVICE(USB_ESDGMBH_VENDOR_ID, USB_CANUSBM_PRODUCT_ID)},
177 {}
178 };
179 MODULE_DEVICE_TABLE(usb, esd_usb2_table);
180
181 struct esd_usb2_net_priv;
182
183 struct esd_tx_urb_context {
184 struct esd_usb2_net_priv *priv;
185 u32 echo_index;
186 int len; /* CAN payload length */
187 };
188
189 struct esd_usb2 {
190 struct usb_device *udev;
191 struct esd_usb2_net_priv *nets[ESD_USB2_MAX_NETS];
192
193 struct usb_anchor rx_submitted;
194
195 int net_count;
196 u32 version;
197 int rxinitdone;
198 void *rxbuf[MAX_RX_URBS];
199 dma_addr_t rxbuf_dma[MAX_RX_URBS];
200 };
201
202 struct esd_usb2_net_priv {
203 struct can_priv can; /* must be the first member */
204
205 atomic_t active_tx_jobs;
206 struct usb_anchor tx_submitted;
207 struct esd_tx_urb_context tx_contexts[MAX_TX_URBS];
208
209 struct esd_usb2 *usb2;
210 struct net_device *netdev;
211 int index;
212 u8 old_state;
213 struct can_berr_counter bec;
214 };
215
esd_usb2_rx_event(struct esd_usb2_net_priv * priv,struct esd_usb2_msg * msg)216 static void esd_usb2_rx_event(struct esd_usb2_net_priv *priv,
217 struct esd_usb2_msg *msg)
218 {
219 struct net_device_stats *stats = &priv->netdev->stats;
220 struct can_frame *cf;
221 struct sk_buff *skb;
222 u32 id = le32_to_cpu(msg->msg.rx.id) & ESD_IDMASK;
223
224 if (id == ESD_EV_CAN_ERROR_EXT) {
225 u8 state = msg->msg.rx.data[0];
226 u8 ecc = msg->msg.rx.data[1];
227 u8 rxerr = msg->msg.rx.data[2];
228 u8 txerr = msg->msg.rx.data[3];
229
230 skb = alloc_can_err_skb(priv->netdev, &cf);
231 if (skb == NULL) {
232 stats->rx_dropped++;
233 return;
234 }
235
236 if (state != priv->old_state) {
237 priv->old_state = state;
238
239 switch (state & ESD_BUSSTATE_MASK) {
240 case ESD_BUSSTATE_BUSOFF:
241 priv->can.state = CAN_STATE_BUS_OFF;
242 cf->can_id |= CAN_ERR_BUSOFF;
243 priv->can.can_stats.bus_off++;
244 can_bus_off(priv->netdev);
245 break;
246 case ESD_BUSSTATE_WARN:
247 priv->can.state = CAN_STATE_ERROR_WARNING;
248 priv->can.can_stats.error_warning++;
249 break;
250 case ESD_BUSSTATE_ERRPASSIVE:
251 priv->can.state = CAN_STATE_ERROR_PASSIVE;
252 priv->can.can_stats.error_passive++;
253 break;
254 default:
255 priv->can.state = CAN_STATE_ERROR_ACTIVE;
256 break;
257 }
258 } else {
259 priv->can.can_stats.bus_error++;
260 stats->rx_errors++;
261
262 cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
263
264 switch (ecc & SJA1000_ECC_MASK) {
265 case SJA1000_ECC_BIT:
266 cf->data[2] |= CAN_ERR_PROT_BIT;
267 break;
268 case SJA1000_ECC_FORM:
269 cf->data[2] |= CAN_ERR_PROT_FORM;
270 break;
271 case SJA1000_ECC_STUFF:
272 cf->data[2] |= CAN_ERR_PROT_STUFF;
273 break;
274 default:
275 cf->data[3] = ecc & SJA1000_ECC_SEG;
276 break;
277 }
278
279 /* Error occurred during transmission? */
280 if (!(ecc & SJA1000_ECC_DIR))
281 cf->data[2] |= CAN_ERR_PROT_TX;
282
283 if (priv->can.state == CAN_STATE_ERROR_WARNING ||
284 priv->can.state == CAN_STATE_ERROR_PASSIVE) {
285 cf->data[1] = (txerr > rxerr) ?
286 CAN_ERR_CRTL_TX_PASSIVE :
287 CAN_ERR_CRTL_RX_PASSIVE;
288 }
289 cf->data[6] = txerr;
290 cf->data[7] = rxerr;
291 }
292
293 priv->bec.txerr = txerr;
294 priv->bec.rxerr = rxerr;
295
296 stats->rx_packets++;
297 stats->rx_bytes += cf->len;
298 netif_rx(skb);
299 }
300 }
301
esd_usb2_rx_can_msg(struct esd_usb2_net_priv * priv,struct esd_usb2_msg * msg)302 static void esd_usb2_rx_can_msg(struct esd_usb2_net_priv *priv,
303 struct esd_usb2_msg *msg)
304 {
305 struct net_device_stats *stats = &priv->netdev->stats;
306 struct can_frame *cf;
307 struct sk_buff *skb;
308 int i;
309 u32 id;
310
311 if (!netif_device_present(priv->netdev))
312 return;
313
314 id = le32_to_cpu(msg->msg.rx.id);
315
316 if (id & ESD_EVENT) {
317 esd_usb2_rx_event(priv, msg);
318 } else {
319 skb = alloc_can_skb(priv->netdev, &cf);
320 if (skb == NULL) {
321 stats->rx_dropped++;
322 return;
323 }
324
325 cf->can_id = id & ESD_IDMASK;
326 can_frame_set_cc_len(cf, msg->msg.rx.dlc & ~ESD_RTR,
327 priv->can.ctrlmode);
328
329 if (id & ESD_EXTID)
330 cf->can_id |= CAN_EFF_FLAG;
331
332 if (msg->msg.rx.dlc & ESD_RTR) {
333 cf->can_id |= CAN_RTR_FLAG;
334 } else {
335 for (i = 0; i < cf->len; i++)
336 cf->data[i] = msg->msg.rx.data[i];
337 }
338
339 stats->rx_packets++;
340 stats->rx_bytes += cf->len;
341 netif_rx(skb);
342 }
343
344 return;
345 }
346
esd_usb2_tx_done_msg(struct esd_usb2_net_priv * priv,struct esd_usb2_msg * msg)347 static void esd_usb2_tx_done_msg(struct esd_usb2_net_priv *priv,
348 struct esd_usb2_msg *msg)
349 {
350 struct net_device_stats *stats = &priv->netdev->stats;
351 struct net_device *netdev = priv->netdev;
352 struct esd_tx_urb_context *context;
353
354 if (!netif_device_present(netdev))
355 return;
356
357 context = &priv->tx_contexts[msg->msg.txdone.hnd & (MAX_TX_URBS - 1)];
358
359 if (!msg->msg.txdone.status) {
360 stats->tx_packets++;
361 stats->tx_bytes += context->len;
362 can_get_echo_skb(netdev, context->echo_index, NULL);
363 } else {
364 stats->tx_errors++;
365 can_free_echo_skb(netdev, context->echo_index, NULL);
366 }
367
368 /* Release context */
369 context->echo_index = MAX_TX_URBS;
370 atomic_dec(&priv->active_tx_jobs);
371
372 netif_wake_queue(netdev);
373 }
374
esd_usb2_read_bulk_callback(struct urb * urb)375 static void esd_usb2_read_bulk_callback(struct urb *urb)
376 {
377 struct esd_usb2 *dev = urb->context;
378 int retval;
379 int pos = 0;
380 int i;
381
382 switch (urb->status) {
383 case 0: /* success */
384 break;
385
386 case -ENOENT:
387 case -EPIPE:
388 case -EPROTO:
389 case -ESHUTDOWN:
390 return;
391
392 default:
393 dev_info(dev->udev->dev.parent,
394 "Rx URB aborted (%d)\n", urb->status);
395 goto resubmit_urb;
396 }
397
398 while (pos < urb->actual_length) {
399 struct esd_usb2_msg *msg;
400
401 msg = (struct esd_usb2_msg *)(urb->transfer_buffer + pos);
402
403 switch (msg->msg.hdr.cmd) {
404 case CMD_CAN_RX:
405 if (msg->msg.rx.net >= dev->net_count) {
406 dev_err(dev->udev->dev.parent, "format error\n");
407 break;
408 }
409
410 esd_usb2_rx_can_msg(dev->nets[msg->msg.rx.net], msg);
411 break;
412
413 case CMD_CAN_TX:
414 if (msg->msg.txdone.net >= dev->net_count) {
415 dev_err(dev->udev->dev.parent, "format error\n");
416 break;
417 }
418
419 esd_usb2_tx_done_msg(dev->nets[msg->msg.txdone.net],
420 msg);
421 break;
422 }
423
424 pos += msg->msg.hdr.len << 2;
425
426 if (pos > urb->actual_length) {
427 dev_err(dev->udev->dev.parent, "format error\n");
428 break;
429 }
430 }
431
432 resubmit_urb:
433 usb_fill_bulk_urb(urb, dev->udev, usb_rcvbulkpipe(dev->udev, 1),
434 urb->transfer_buffer, RX_BUFFER_SIZE,
435 esd_usb2_read_bulk_callback, dev);
436
437 retval = usb_submit_urb(urb, GFP_ATOMIC);
438 if (retval == -ENODEV) {
439 for (i = 0; i < dev->net_count; i++) {
440 if (dev->nets[i])
441 netif_device_detach(dev->nets[i]->netdev);
442 }
443 } else if (retval) {
444 dev_err(dev->udev->dev.parent,
445 "failed resubmitting read bulk urb: %d\n", retval);
446 }
447
448 return;
449 }
450
451 /*
452 * callback for bulk IN urb
453 */
esd_usb2_write_bulk_callback(struct urb * urb)454 static void esd_usb2_write_bulk_callback(struct urb *urb)
455 {
456 struct esd_tx_urb_context *context = urb->context;
457 struct esd_usb2_net_priv *priv;
458 struct net_device *netdev;
459 size_t size = sizeof(struct esd_usb2_msg);
460
461 WARN_ON(!context);
462
463 priv = context->priv;
464 netdev = priv->netdev;
465
466 /* free up our allocated buffer */
467 usb_free_coherent(urb->dev, size,
468 urb->transfer_buffer, urb->transfer_dma);
469
470 if (!netif_device_present(netdev))
471 return;
472
473 if (urb->status)
474 netdev_info(netdev, "Tx URB aborted (%d)\n", urb->status);
475
476 netif_trans_update(netdev);
477 }
478
firmware_show(struct device * d,struct device_attribute * attr,char * buf)479 static ssize_t firmware_show(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_RO(firmware);
491
hardware_show(struct device * d,struct device_attribute * attr,char * buf)492 static ssize_t hardware_show(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_RO(hardware);
504
nets_show(struct device * d,struct device_attribute * attr,char * buf)505 static ssize_t nets_show(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_RO(nets);
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 dma_addr_t buf_dma;
551
552 /* create a URB, and a buffer for it */
553 urb = usb_alloc_urb(0, GFP_KERNEL);
554 if (!urb) {
555 err = -ENOMEM;
556 break;
557 }
558
559 buf = usb_alloc_coherent(dev->udev, RX_BUFFER_SIZE, GFP_KERNEL,
560 &buf_dma);
561 if (!buf) {
562 dev_warn(dev->udev->dev.parent,
563 "No memory left for USB buffer\n");
564 err = -ENOMEM;
565 goto freeurb;
566 }
567
568 urb->transfer_dma = buf_dma;
569
570 usb_fill_bulk_urb(urb, dev->udev,
571 usb_rcvbulkpipe(dev->udev, 1),
572 buf, RX_BUFFER_SIZE,
573 esd_usb2_read_bulk_callback, dev);
574 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
575 usb_anchor_urb(urb, &dev->rx_submitted);
576
577 err = usb_submit_urb(urb, GFP_KERNEL);
578 if (err) {
579 usb_unanchor_urb(urb);
580 usb_free_coherent(dev->udev, RX_BUFFER_SIZE, buf,
581 urb->transfer_dma);
582 goto freeurb;
583 }
584
585 dev->rxbuf[i] = buf;
586 dev->rxbuf_dma[i] = buf_dma;
587
588 freeurb:
589 /* Drop reference, USB core will take care of freeing it */
590 usb_free_urb(urb);
591 if (err)
592 break;
593 }
594
595 /* Did we submit any URBs */
596 if (i == 0) {
597 dev_err(dev->udev->dev.parent, "couldn't setup read URBs\n");
598 return err;
599 }
600
601 /* Warn if we've couldn't transmit all the URBs */
602 if (i < MAX_RX_URBS) {
603 dev_warn(dev->udev->dev.parent,
604 "rx performance may be slow\n");
605 }
606
607 dev->rxinitdone = 1;
608 return 0;
609 }
610
611 /*
612 * Start interface
613 */
esd_usb2_start(struct esd_usb2_net_priv * priv)614 static int esd_usb2_start(struct esd_usb2_net_priv *priv)
615 {
616 struct esd_usb2 *dev = priv->usb2;
617 struct net_device *netdev = priv->netdev;
618 struct esd_usb2_msg *msg;
619 int err, i;
620
621 msg = kmalloc(sizeof(*msg), GFP_KERNEL);
622 if (!msg) {
623 err = -ENOMEM;
624 goto out;
625 }
626
627 /*
628 * Enable all IDs
629 * The IDADD message takes up to 64 32 bit bitmasks (2048 bits).
630 * Each bit represents one 11 bit CAN identifier. A set bit
631 * enables reception of the corresponding CAN identifier. A cleared
632 * bit disabled this identifier. An additional bitmask value
633 * following the CAN 2.0A bits is used to enable reception of
634 * extended CAN frames. Only the LSB of this final mask is checked
635 * for the complete 29 bit ID range. The IDADD message also allows
636 * filter configuration for an ID subset. In this case you can add
637 * the number of the starting bitmask (0..64) to the filter.option
638 * field followed by only some bitmasks.
639 */
640 msg->msg.hdr.cmd = CMD_IDADD;
641 msg->msg.hdr.len = 2 + ESD_MAX_ID_SEGMENT;
642 msg->msg.filter.net = priv->index;
643 msg->msg.filter.option = ESD_ID_ENABLE; /* start with segment 0 */
644 for (i = 0; i < ESD_MAX_ID_SEGMENT; i++)
645 msg->msg.filter.mask[i] = cpu_to_le32(0xffffffff);
646 /* enable 29bit extended IDs */
647 msg->msg.filter.mask[ESD_MAX_ID_SEGMENT] = cpu_to_le32(0x00000001);
648
649 err = esd_usb2_send_msg(dev, msg);
650 if (err)
651 goto out;
652
653 err = esd_usb2_setup_rx_urbs(dev);
654 if (err)
655 goto out;
656
657 priv->can.state = CAN_STATE_ERROR_ACTIVE;
658
659 out:
660 if (err == -ENODEV)
661 netif_device_detach(netdev);
662 if (err)
663 netdev_err(netdev, "couldn't start device: %d\n", err);
664
665 kfree(msg);
666 return err;
667 }
668
unlink_all_urbs(struct esd_usb2 * dev)669 static void unlink_all_urbs(struct esd_usb2 *dev)
670 {
671 struct esd_usb2_net_priv *priv;
672 int i, j;
673
674 usb_kill_anchored_urbs(&dev->rx_submitted);
675
676 for (i = 0; i < MAX_RX_URBS; ++i)
677 usb_free_coherent(dev->udev, RX_BUFFER_SIZE,
678 dev->rxbuf[i], dev->rxbuf_dma[i]);
679
680 for (i = 0; i < dev->net_count; i++) {
681 priv = dev->nets[i];
682 if (priv) {
683 usb_kill_anchored_urbs(&priv->tx_submitted);
684 atomic_set(&priv->active_tx_jobs, 0);
685
686 for (j = 0; j < MAX_TX_URBS; j++)
687 priv->tx_contexts[j].echo_index = MAX_TX_URBS;
688 }
689 }
690 }
691
esd_usb2_open(struct net_device * netdev)692 static int esd_usb2_open(struct net_device *netdev)
693 {
694 struct esd_usb2_net_priv *priv = netdev_priv(netdev);
695 int err;
696
697 /* common open */
698 err = open_candev(netdev);
699 if (err)
700 return err;
701
702 /* finally start device */
703 err = esd_usb2_start(priv);
704 if (err) {
705 netdev_warn(netdev, "couldn't start device: %d\n", err);
706 close_candev(netdev);
707 return err;
708 }
709
710 netif_start_queue(netdev);
711
712 return 0;
713 }
714
esd_usb2_start_xmit(struct sk_buff * skb,struct net_device * netdev)715 static netdev_tx_t esd_usb2_start_xmit(struct sk_buff *skb,
716 struct net_device *netdev)
717 {
718 struct esd_usb2_net_priv *priv = netdev_priv(netdev);
719 struct esd_usb2 *dev = priv->usb2;
720 struct esd_tx_urb_context *context = NULL;
721 struct net_device_stats *stats = &netdev->stats;
722 struct can_frame *cf = (struct can_frame *)skb->data;
723 struct esd_usb2_msg *msg;
724 struct urb *urb;
725 u8 *buf;
726 int i, err;
727 int ret = NETDEV_TX_OK;
728 size_t size = sizeof(struct esd_usb2_msg);
729
730 if (can_dropped_invalid_skb(netdev, skb))
731 return NETDEV_TX_OK;
732
733 /* create a URB, and a buffer for it, and copy the data to the URB */
734 urb = usb_alloc_urb(0, GFP_ATOMIC);
735 if (!urb) {
736 stats->tx_dropped++;
737 dev_kfree_skb(skb);
738 goto nourbmem;
739 }
740
741 buf = usb_alloc_coherent(dev->udev, size, GFP_ATOMIC,
742 &urb->transfer_dma);
743 if (!buf) {
744 netdev_err(netdev, "No memory left for USB buffer\n");
745 stats->tx_dropped++;
746 dev_kfree_skb(skb);
747 goto nobufmem;
748 }
749
750 msg = (struct esd_usb2_msg *)buf;
751
752 msg->msg.hdr.len = 3; /* minimal length */
753 msg->msg.hdr.cmd = CMD_CAN_TX;
754 msg->msg.tx.net = priv->index;
755 msg->msg.tx.dlc = can_get_cc_dlc(cf, priv->can.ctrlmode);
756 msg->msg.tx.id = cpu_to_le32(cf->can_id & CAN_ERR_MASK);
757
758 if (cf->can_id & CAN_RTR_FLAG)
759 msg->msg.tx.dlc |= ESD_RTR;
760
761 if (cf->can_id & CAN_EFF_FLAG)
762 msg->msg.tx.id |= cpu_to_le32(ESD_EXTID);
763
764 for (i = 0; i < cf->len; i++)
765 msg->msg.tx.data[i] = cf->data[i];
766
767 msg->msg.hdr.len += (cf->len + 3) >> 2;
768
769 for (i = 0; i < MAX_TX_URBS; i++) {
770 if (priv->tx_contexts[i].echo_index == MAX_TX_URBS) {
771 context = &priv->tx_contexts[i];
772 break;
773 }
774 }
775
776 /*
777 * This may never happen.
778 */
779 if (!context) {
780 netdev_warn(netdev, "couldn't find free context\n");
781 ret = NETDEV_TX_BUSY;
782 goto releasebuf;
783 }
784
785 context->priv = priv;
786 context->echo_index = i;
787 context->len = cf->len;
788
789 /* hnd must not be 0 - MSB is stripped in txdone handling */
790 msg->msg.tx.hnd = 0x80000000 | i; /* returned in TX done message */
791
792 usb_fill_bulk_urb(urb, dev->udev, usb_sndbulkpipe(dev->udev, 2), buf,
793 msg->msg.hdr.len << 2,
794 esd_usb2_write_bulk_callback, context);
795
796 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
797
798 usb_anchor_urb(urb, &priv->tx_submitted);
799
800 can_put_echo_skb(skb, netdev, context->echo_index, 0);
801
802 atomic_inc(&priv->active_tx_jobs);
803
804 /* Slow down tx path */
805 if (atomic_read(&priv->active_tx_jobs) >= MAX_TX_URBS)
806 netif_stop_queue(netdev);
807
808 err = usb_submit_urb(urb, GFP_ATOMIC);
809 if (err) {
810 can_free_echo_skb(netdev, context->echo_index, NULL);
811
812 atomic_dec(&priv->active_tx_jobs);
813 usb_unanchor_urb(urb);
814
815 stats->tx_dropped++;
816
817 if (err == -ENODEV)
818 netif_device_detach(netdev);
819 else
820 netdev_warn(netdev, "failed tx_urb %d\n", err);
821
822 goto releasebuf;
823 }
824
825 netif_trans_update(netdev);
826
827 /*
828 * Release our reference to this URB, the USB core will eventually free
829 * it entirely.
830 */
831 usb_free_urb(urb);
832
833 return NETDEV_TX_OK;
834
835 releasebuf:
836 usb_free_coherent(dev->udev, size, buf, urb->transfer_dma);
837
838 nobufmem:
839 usb_free_urb(urb);
840
841 nourbmem:
842 return ret;
843 }
844
esd_usb2_close(struct net_device * netdev)845 static int esd_usb2_close(struct net_device *netdev)
846 {
847 struct esd_usb2_net_priv *priv = netdev_priv(netdev);
848 struct esd_usb2_msg *msg;
849 int i;
850
851 msg = kmalloc(sizeof(*msg), GFP_KERNEL);
852 if (!msg)
853 return -ENOMEM;
854
855 /* Disable all IDs (see esd_usb2_start()) */
856 msg->msg.hdr.cmd = CMD_IDADD;
857 msg->msg.hdr.len = 2 + ESD_MAX_ID_SEGMENT;
858 msg->msg.filter.net = priv->index;
859 msg->msg.filter.option = ESD_ID_ENABLE; /* start with segment 0 */
860 for (i = 0; i <= ESD_MAX_ID_SEGMENT; i++)
861 msg->msg.filter.mask[i] = 0;
862 if (esd_usb2_send_msg(priv->usb2, msg) < 0)
863 netdev_err(netdev, "sending idadd message failed\n");
864
865 /* set CAN controller to reset mode */
866 msg->msg.hdr.len = 2;
867 msg->msg.hdr.cmd = CMD_SETBAUD;
868 msg->msg.setbaud.net = priv->index;
869 msg->msg.setbaud.rsvd = 0;
870 msg->msg.setbaud.baud = cpu_to_le32(ESD_USB2_NO_BAUDRATE);
871 if (esd_usb2_send_msg(priv->usb2, msg) < 0)
872 netdev_err(netdev, "sending setbaud message failed\n");
873
874 priv->can.state = CAN_STATE_STOPPED;
875
876 netif_stop_queue(netdev);
877
878 close_candev(netdev);
879
880 kfree(msg);
881
882 return 0;
883 }
884
885 static const struct net_device_ops esd_usb2_netdev_ops = {
886 .ndo_open = esd_usb2_open,
887 .ndo_stop = esd_usb2_close,
888 .ndo_start_xmit = esd_usb2_start_xmit,
889 .ndo_change_mtu = can_change_mtu,
890 };
891
892 static const struct can_bittiming_const esd_usb2_bittiming_const = {
893 .name = "esd_usb2",
894 .tseg1_min = ESD_USB2_TSEG1_MIN,
895 .tseg1_max = ESD_USB2_TSEG1_MAX,
896 .tseg2_min = ESD_USB2_TSEG2_MIN,
897 .tseg2_max = ESD_USB2_TSEG2_MAX,
898 .sjw_max = ESD_USB2_SJW_MAX,
899 .brp_min = ESD_USB2_BRP_MIN,
900 .brp_max = ESD_USB2_BRP_MAX,
901 .brp_inc = ESD_USB2_BRP_INC,
902 };
903
esd_usb2_set_bittiming(struct net_device * netdev)904 static int esd_usb2_set_bittiming(struct net_device *netdev)
905 {
906 struct esd_usb2_net_priv *priv = netdev_priv(netdev);
907 struct can_bittiming *bt = &priv->can.bittiming;
908 struct esd_usb2_msg *msg;
909 int err;
910 u32 canbtr;
911 int sjw_shift;
912
913 canbtr = ESD_USB2_UBR;
914 if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
915 canbtr |= ESD_USB2_LOM;
916
917 canbtr |= (bt->brp - 1) & (ESD_USB2_BRP_MAX - 1);
918
919 if (le16_to_cpu(priv->usb2->udev->descriptor.idProduct) ==
920 USB_CANUSBM_PRODUCT_ID)
921 sjw_shift = ESD_USBM_SJW_SHIFT;
922 else
923 sjw_shift = ESD_USB2_SJW_SHIFT;
924
925 canbtr |= ((bt->sjw - 1) & (ESD_USB2_SJW_MAX - 1))
926 << sjw_shift;
927 canbtr |= ((bt->prop_seg + bt->phase_seg1 - 1)
928 & (ESD_USB2_TSEG1_MAX - 1))
929 << ESD_USB2_TSEG1_SHIFT;
930 canbtr |= ((bt->phase_seg2 - 1) & (ESD_USB2_TSEG2_MAX - 1))
931 << ESD_USB2_TSEG2_SHIFT;
932 if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
933 canbtr |= ESD_USB2_3_SAMPLES;
934
935 msg = kmalloc(sizeof(*msg), GFP_KERNEL);
936 if (!msg)
937 return -ENOMEM;
938
939 msg->msg.hdr.len = 2;
940 msg->msg.hdr.cmd = CMD_SETBAUD;
941 msg->msg.setbaud.net = priv->index;
942 msg->msg.setbaud.rsvd = 0;
943 msg->msg.setbaud.baud = cpu_to_le32(canbtr);
944
945 netdev_info(netdev, "setting BTR=%#x\n", canbtr);
946
947 err = esd_usb2_send_msg(priv->usb2, msg);
948
949 kfree(msg);
950 return err;
951 }
952
esd_usb2_get_berr_counter(const struct net_device * netdev,struct can_berr_counter * bec)953 static int esd_usb2_get_berr_counter(const struct net_device *netdev,
954 struct can_berr_counter *bec)
955 {
956 struct esd_usb2_net_priv *priv = netdev_priv(netdev);
957
958 bec->txerr = priv->bec.txerr;
959 bec->rxerr = priv->bec.rxerr;
960
961 return 0;
962 }
963
esd_usb2_set_mode(struct net_device * netdev,enum can_mode mode)964 static int esd_usb2_set_mode(struct net_device *netdev, enum can_mode mode)
965 {
966 switch (mode) {
967 case CAN_MODE_START:
968 netif_wake_queue(netdev);
969 break;
970
971 default:
972 return -EOPNOTSUPP;
973 }
974
975 return 0;
976 }
977
esd_usb2_probe_one_net(struct usb_interface * intf,int index)978 static int esd_usb2_probe_one_net(struct usb_interface *intf, int index)
979 {
980 struct esd_usb2 *dev = usb_get_intfdata(intf);
981 struct net_device *netdev;
982 struct esd_usb2_net_priv *priv;
983 int err = 0;
984 int i;
985
986 netdev = alloc_candev(sizeof(*priv), MAX_TX_URBS);
987 if (!netdev) {
988 dev_err(&intf->dev, "couldn't alloc candev\n");
989 err = -ENOMEM;
990 goto done;
991 }
992
993 priv = netdev_priv(netdev);
994
995 init_usb_anchor(&priv->tx_submitted);
996 atomic_set(&priv->active_tx_jobs, 0);
997
998 for (i = 0; i < MAX_TX_URBS; i++)
999 priv->tx_contexts[i].echo_index = MAX_TX_URBS;
1000
1001 priv->usb2 = dev;
1002 priv->netdev = netdev;
1003 priv->index = index;
1004
1005 priv->can.state = CAN_STATE_STOPPED;
1006 priv->can.ctrlmode_supported = CAN_CTRLMODE_LISTENONLY |
1007 CAN_CTRLMODE_CC_LEN8_DLC;
1008
1009 if (le16_to_cpu(dev->udev->descriptor.idProduct) ==
1010 USB_CANUSBM_PRODUCT_ID)
1011 priv->can.clock.freq = ESD_USBM_CAN_CLOCK;
1012 else {
1013 priv->can.clock.freq = ESD_USB2_CAN_CLOCK;
1014 priv->can.ctrlmode_supported |= CAN_CTRLMODE_3_SAMPLES;
1015 }
1016
1017 priv->can.bittiming_const = &esd_usb2_bittiming_const;
1018 priv->can.do_set_bittiming = esd_usb2_set_bittiming;
1019 priv->can.do_set_mode = esd_usb2_set_mode;
1020 priv->can.do_get_berr_counter = esd_usb2_get_berr_counter;
1021
1022 netdev->flags |= IFF_ECHO; /* we support local echo */
1023
1024 netdev->netdev_ops = &esd_usb2_netdev_ops;
1025
1026 SET_NETDEV_DEV(netdev, &intf->dev);
1027 netdev->dev_id = index;
1028
1029 err = register_candev(netdev);
1030 if (err) {
1031 dev_err(&intf->dev, "couldn't register CAN device: %d\n", err);
1032 free_candev(netdev);
1033 err = -ENOMEM;
1034 goto done;
1035 }
1036
1037 dev->nets[index] = priv;
1038 netdev_info(netdev, "device %s registered\n", netdev->name);
1039
1040 done:
1041 return err;
1042 }
1043
1044 /*
1045 * probe function for new USB2 devices
1046 *
1047 * check version information and number of available
1048 * CAN interfaces
1049 */
esd_usb2_probe(struct usb_interface * intf,const struct usb_device_id * id)1050 static int esd_usb2_probe(struct usb_interface *intf,
1051 const struct usb_device_id *id)
1052 {
1053 struct esd_usb2 *dev;
1054 struct esd_usb2_msg *msg;
1055 int i, err;
1056
1057 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1058 if (!dev) {
1059 err = -ENOMEM;
1060 goto done;
1061 }
1062
1063 dev->udev = interface_to_usbdev(intf);
1064
1065 init_usb_anchor(&dev->rx_submitted);
1066
1067 usb_set_intfdata(intf, dev);
1068
1069 msg = kmalloc(sizeof(*msg), GFP_KERNEL);
1070 if (!msg) {
1071 err = -ENOMEM;
1072 goto free_msg;
1073 }
1074
1075 /* query number of CAN interfaces (nets) */
1076 msg->msg.hdr.cmd = CMD_VERSION;
1077 msg->msg.hdr.len = 2;
1078 msg->msg.version.rsvd = 0;
1079 msg->msg.version.flags = 0;
1080 msg->msg.version.drv_version = 0;
1081
1082 err = esd_usb2_send_msg(dev, msg);
1083 if (err < 0) {
1084 dev_err(&intf->dev, "sending version message failed\n");
1085 goto free_msg;
1086 }
1087
1088 err = esd_usb2_wait_msg(dev, msg);
1089 if (err < 0) {
1090 dev_err(&intf->dev, "no version message answer\n");
1091 goto free_msg;
1092 }
1093
1094 dev->net_count = (int)msg->msg.version_reply.nets;
1095 dev->version = le32_to_cpu(msg->msg.version_reply.version);
1096
1097 if (device_create_file(&intf->dev, &dev_attr_firmware))
1098 dev_err(&intf->dev,
1099 "Couldn't create device file for firmware\n");
1100
1101 if (device_create_file(&intf->dev, &dev_attr_hardware))
1102 dev_err(&intf->dev,
1103 "Couldn't create device file for hardware\n");
1104
1105 if (device_create_file(&intf->dev, &dev_attr_nets))
1106 dev_err(&intf->dev,
1107 "Couldn't create device file for nets\n");
1108
1109 /* do per device probing */
1110 for (i = 0; i < dev->net_count; i++)
1111 esd_usb2_probe_one_net(intf, i);
1112
1113 free_msg:
1114 kfree(msg);
1115 if (err)
1116 kfree(dev);
1117 done:
1118 return err;
1119 }
1120
1121 /*
1122 * called by the usb core when the device is removed from the system
1123 */
esd_usb2_disconnect(struct usb_interface * intf)1124 static void esd_usb2_disconnect(struct usb_interface *intf)
1125 {
1126 struct esd_usb2 *dev = usb_get_intfdata(intf);
1127 struct net_device *netdev;
1128 int i;
1129
1130 device_remove_file(&intf->dev, &dev_attr_firmware);
1131 device_remove_file(&intf->dev, &dev_attr_hardware);
1132 device_remove_file(&intf->dev, &dev_attr_nets);
1133
1134 usb_set_intfdata(intf, NULL);
1135
1136 if (dev) {
1137 for (i = 0; i < dev->net_count; i++) {
1138 if (dev->nets[i]) {
1139 netdev = dev->nets[i]->netdev;
1140 unregister_netdev(netdev);
1141 free_candev(netdev);
1142 }
1143 }
1144 unlink_all_urbs(dev);
1145 kfree(dev);
1146 }
1147 }
1148
1149 /* usb specific object needed to register this driver with the usb subsystem */
1150 static struct usb_driver esd_usb2_driver = {
1151 .name = "esd_usb2",
1152 .probe = esd_usb2_probe,
1153 .disconnect = esd_usb2_disconnect,
1154 .id_table = esd_usb2_table,
1155 };
1156
1157 module_usb_driver(esd_usb2_driver);
1158
