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 netdev_dbg(priv->netdev,
231 "CAN_ERR_EV_EXT: dlc=%#02x state=%02x ecc=%02x rec=%02x tec=%02x\n",
232 msg->msg.rx.dlc, state, ecc, rxerr, txerr);
233
234 skb = alloc_can_err_skb(priv->netdev, &cf);
235 if (skb == NULL) {
236 stats->rx_dropped++;
237 return;
238 }
239
240 if (state != priv->old_state) {
241 priv->old_state = state;
242
243 switch (state & ESD_BUSSTATE_MASK) {
244 case ESD_BUSSTATE_BUSOFF:
245 priv->can.state = CAN_STATE_BUS_OFF;
246 cf->can_id |= CAN_ERR_BUSOFF;
247 priv->can.can_stats.bus_off++;
248 can_bus_off(priv->netdev);
249 break;
250 case ESD_BUSSTATE_WARN:
251 priv->can.state = CAN_STATE_ERROR_WARNING;
252 priv->can.can_stats.error_warning++;
253 break;
254 case ESD_BUSSTATE_ERRPASSIVE:
255 priv->can.state = CAN_STATE_ERROR_PASSIVE;
256 priv->can.can_stats.error_passive++;
257 break;
258 default:
259 priv->can.state = CAN_STATE_ERROR_ACTIVE;
260 txerr = 0;
261 rxerr = 0;
262 break;
263 }
264 } else {
265 priv->can.can_stats.bus_error++;
266 stats->rx_errors++;
267
268 cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
269
270 switch (ecc & SJA1000_ECC_MASK) {
271 case SJA1000_ECC_BIT:
272 cf->data[2] |= CAN_ERR_PROT_BIT;
273 break;
274 case SJA1000_ECC_FORM:
275 cf->data[2] |= CAN_ERR_PROT_FORM;
276 break;
277 case SJA1000_ECC_STUFF:
278 cf->data[2] |= CAN_ERR_PROT_STUFF;
279 break;
280 default:
281 break;
282 }
283
284 /* Error occurred during transmission? */
285 if (!(ecc & SJA1000_ECC_DIR))
286 cf->data[2] |= CAN_ERR_PROT_TX;
287
288 /* Bit stream position in CAN frame as the error was detected */
289 cf->data[3] = ecc & SJA1000_ECC_SEG;
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 priv->bec.txerr = txerr;
302 priv->bec.rxerr = rxerr;
303
304 stats->rx_packets++;
305 stats->rx_bytes += cf->len;
306 netif_rx(skb);
307 }
308 }
309
esd_usb2_rx_can_msg(struct esd_usb2_net_priv * priv,struct esd_usb2_msg * msg)310 static void esd_usb2_rx_can_msg(struct esd_usb2_net_priv *priv,
311 struct esd_usb2_msg *msg)
312 {
313 struct net_device_stats *stats = &priv->netdev->stats;
314 struct can_frame *cf;
315 struct sk_buff *skb;
316 int i;
317 u32 id;
318
319 if (!netif_device_present(priv->netdev))
320 return;
321
322 id = le32_to_cpu(msg->msg.rx.id);
323
324 if (id & ESD_EVENT) {
325 esd_usb2_rx_event(priv, msg);
326 } else {
327 skb = alloc_can_skb(priv->netdev, &cf);
328 if (skb == NULL) {
329 stats->rx_dropped++;
330 return;
331 }
332
333 cf->can_id = id & ESD_IDMASK;
334 can_frame_set_cc_len(cf, msg->msg.rx.dlc & ~ESD_RTR,
335 priv->can.ctrlmode);
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->len; i++)
344 cf->data[i] = msg->msg.rx.data[i];
345 }
346
347 stats->rx_packets++;
348 stats->rx_bytes += cf->len;
349 netif_rx(skb);
350 }
351
352 return;
353 }
354
esd_usb2_tx_done_msg(struct esd_usb2_net_priv * priv,struct esd_usb2_msg * msg)355 static void esd_usb2_tx_done_msg(struct esd_usb2_net_priv *priv,
356 struct esd_usb2_msg *msg)
357 {
358 struct net_device_stats *stats = &priv->netdev->stats;
359 struct net_device *netdev = priv->netdev;
360 struct esd_tx_urb_context *context;
361
362 if (!netif_device_present(netdev))
363 return;
364
365 context = &priv->tx_contexts[msg->msg.txdone.hnd & (MAX_TX_URBS - 1)];
366
367 if (!msg->msg.txdone.status) {
368 stats->tx_packets++;
369 stats->tx_bytes += context->len;
370 can_get_echo_skb(netdev, context->echo_index, NULL);
371 } else {
372 stats->tx_errors++;
373 can_free_echo_skb(netdev, context->echo_index, NULL);
374 }
375
376 /* Release context */
377 context->echo_index = MAX_TX_URBS;
378 atomic_dec(&priv->active_tx_jobs);
379
380 netif_wake_queue(netdev);
381 }
382
esd_usb2_read_bulk_callback(struct urb * urb)383 static void esd_usb2_read_bulk_callback(struct urb *urb)
384 {
385 struct esd_usb2 *dev = urb->context;
386 int retval;
387 int pos = 0;
388 int i;
389
390 switch (urb->status) {
391 case 0: /* success */
392 break;
393
394 case -ENOENT:
395 case -EPIPE:
396 case -EPROTO:
397 case -ESHUTDOWN:
398 return;
399
400 default:
401 dev_info(dev->udev->dev.parent,
402 "Rx URB aborted (%d)\n", urb->status);
403 goto resubmit_urb;
404 }
405
406 while (pos < urb->actual_length) {
407 struct esd_usb2_msg *msg;
408
409 msg = (struct esd_usb2_msg *)(urb->transfer_buffer + pos);
410
411 switch (msg->msg.hdr.cmd) {
412 case CMD_CAN_RX:
413 if (msg->msg.rx.net >= dev->net_count) {
414 dev_err(dev->udev->dev.parent, "format error\n");
415 break;
416 }
417
418 esd_usb2_rx_can_msg(dev->nets[msg->msg.rx.net], msg);
419 break;
420
421 case CMD_CAN_TX:
422 if (msg->msg.txdone.net >= dev->net_count) {
423 dev_err(dev->udev->dev.parent, "format error\n");
424 break;
425 }
426
427 esd_usb2_tx_done_msg(dev->nets[msg->msg.txdone.net],
428 msg);
429 break;
430 }
431
432 pos += msg->msg.hdr.len << 2;
433
434 if (pos > urb->actual_length) {
435 dev_err(dev->udev->dev.parent, "format error\n");
436 break;
437 }
438 }
439
440 resubmit_urb:
441 usb_fill_bulk_urb(urb, dev->udev, usb_rcvbulkpipe(dev->udev, 1),
442 urb->transfer_buffer, RX_BUFFER_SIZE,
443 esd_usb2_read_bulk_callback, dev);
444
445 retval = usb_submit_urb(urb, GFP_ATOMIC);
446 if (retval == -ENODEV) {
447 for (i = 0; i < dev->net_count; i++) {
448 if (dev->nets[i])
449 netif_device_detach(dev->nets[i]->netdev);
450 }
451 } else if (retval) {
452 dev_err(dev->udev->dev.parent,
453 "failed resubmitting read bulk urb: %d\n", retval);
454 }
455
456 return;
457 }
458
459 /*
460 * callback for bulk IN urb
461 */
esd_usb2_write_bulk_callback(struct urb * urb)462 static void esd_usb2_write_bulk_callback(struct urb *urb)
463 {
464 struct esd_tx_urb_context *context = urb->context;
465 struct esd_usb2_net_priv *priv;
466 struct net_device *netdev;
467 size_t size = sizeof(struct esd_usb2_msg);
468
469 WARN_ON(!context);
470
471 priv = context->priv;
472 netdev = priv->netdev;
473
474 /* free up our allocated buffer */
475 usb_free_coherent(urb->dev, size,
476 urb->transfer_buffer, urb->transfer_dma);
477
478 if (!netif_device_present(netdev))
479 return;
480
481 if (urb->status)
482 netdev_info(netdev, "Tx URB aborted (%d)\n", urb->status);
483
484 netif_trans_update(netdev);
485 }
486
firmware_show(struct device * d,struct device_attribute * attr,char * buf)487 static ssize_t firmware_show(struct device *d,
488 struct device_attribute *attr, char *buf)
489 {
490 struct usb_interface *intf = to_usb_interface(d);
491 struct esd_usb2 *dev = usb_get_intfdata(intf);
492
493 return sprintf(buf, "%d.%d.%d\n",
494 (dev->version >> 12) & 0xf,
495 (dev->version >> 8) & 0xf,
496 dev->version & 0xff);
497 }
498 static DEVICE_ATTR_RO(firmware);
499
hardware_show(struct device * d,struct device_attribute * attr,char * buf)500 static ssize_t hardware_show(struct device *d,
501 struct device_attribute *attr, char *buf)
502 {
503 struct usb_interface *intf = to_usb_interface(d);
504 struct esd_usb2 *dev = usb_get_intfdata(intf);
505
506 return sprintf(buf, "%d.%d.%d\n",
507 (dev->version >> 28) & 0xf,
508 (dev->version >> 24) & 0xf,
509 (dev->version >> 16) & 0xff);
510 }
511 static DEVICE_ATTR_RO(hardware);
512
nets_show(struct device * d,struct device_attribute * attr,char * buf)513 static ssize_t nets_show(struct device *d,
514 struct device_attribute *attr, char *buf)
515 {
516 struct usb_interface *intf = to_usb_interface(d);
517 struct esd_usb2 *dev = usb_get_intfdata(intf);
518
519 return sprintf(buf, "%d", dev->net_count);
520 }
521 static DEVICE_ATTR_RO(nets);
522
esd_usb2_send_msg(struct esd_usb2 * dev,struct esd_usb2_msg * msg)523 static int esd_usb2_send_msg(struct esd_usb2 *dev, struct esd_usb2_msg *msg)
524 {
525 int actual_length;
526
527 return usb_bulk_msg(dev->udev,
528 usb_sndbulkpipe(dev->udev, 2),
529 msg,
530 msg->msg.hdr.len << 2,
531 &actual_length,
532 1000);
533 }
534
esd_usb2_wait_msg(struct esd_usb2 * dev,struct esd_usb2_msg * msg)535 static int esd_usb2_wait_msg(struct esd_usb2 *dev,
536 struct esd_usb2_msg *msg)
537 {
538 int actual_length;
539
540 return usb_bulk_msg(dev->udev,
541 usb_rcvbulkpipe(dev->udev, 1),
542 msg,
543 sizeof(*msg),
544 &actual_length,
545 1000);
546 }
547
esd_usb2_setup_rx_urbs(struct esd_usb2 * dev)548 static int esd_usb2_setup_rx_urbs(struct esd_usb2 *dev)
549 {
550 int i, err = 0;
551
552 if (dev->rxinitdone)
553 return 0;
554
555 for (i = 0; i < MAX_RX_URBS; i++) {
556 struct urb *urb = NULL;
557 u8 *buf = NULL;
558 dma_addr_t buf_dma;
559
560 /* create a URB, and a buffer for it */
561 urb = usb_alloc_urb(0, GFP_KERNEL);
562 if (!urb) {
563 err = -ENOMEM;
564 break;
565 }
566
567 buf = usb_alloc_coherent(dev->udev, RX_BUFFER_SIZE, GFP_KERNEL,
568 &buf_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 urb->transfer_dma = buf_dma;
577
578 usb_fill_bulk_urb(urb, dev->udev,
579 usb_rcvbulkpipe(dev->udev, 1),
580 buf, RX_BUFFER_SIZE,
581 esd_usb2_read_bulk_callback, dev);
582 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
583 usb_anchor_urb(urb, &dev->rx_submitted);
584
585 err = usb_submit_urb(urb, GFP_KERNEL);
586 if (err) {
587 usb_unanchor_urb(urb);
588 usb_free_coherent(dev->udev, RX_BUFFER_SIZE, buf,
589 urb->transfer_dma);
590 goto freeurb;
591 }
592
593 dev->rxbuf[i] = buf;
594 dev->rxbuf_dma[i] = buf_dma;
595
596 freeurb:
597 /* Drop reference, USB core will take care of freeing it */
598 usb_free_urb(urb);
599 if (err)
600 break;
601 }
602
603 /* Did we submit any URBs */
604 if (i == 0) {
605 dev_err(dev->udev->dev.parent, "couldn't setup read URBs\n");
606 return err;
607 }
608
609 /* Warn if we've couldn't transmit all the URBs */
610 if (i < MAX_RX_URBS) {
611 dev_warn(dev->udev->dev.parent,
612 "rx performance may be slow\n");
613 }
614
615 dev->rxinitdone = 1;
616 return 0;
617 }
618
619 /*
620 * Start interface
621 */
esd_usb2_start(struct esd_usb2_net_priv * priv)622 static int esd_usb2_start(struct esd_usb2_net_priv *priv)
623 {
624 struct esd_usb2 *dev = priv->usb2;
625 struct net_device *netdev = priv->netdev;
626 struct esd_usb2_msg *msg;
627 int err, i;
628
629 msg = kmalloc(sizeof(*msg), GFP_KERNEL);
630 if (!msg) {
631 err = -ENOMEM;
632 goto out;
633 }
634
635 /*
636 * Enable all IDs
637 * The IDADD message takes up to 64 32 bit bitmasks (2048 bits).
638 * Each bit represents one 11 bit CAN identifier. A set bit
639 * enables reception of the corresponding CAN identifier. A cleared
640 * bit disabled this identifier. An additional bitmask value
641 * following the CAN 2.0A bits is used to enable reception of
642 * extended CAN frames. Only the LSB of this final mask is checked
643 * for the complete 29 bit ID range. The IDADD message also allows
644 * filter configuration for an ID subset. In this case you can add
645 * the number of the starting bitmask (0..64) to the filter.option
646 * field followed by only some bitmasks.
647 */
648 msg->msg.hdr.cmd = CMD_IDADD;
649 msg->msg.hdr.len = 2 + ESD_MAX_ID_SEGMENT;
650 msg->msg.filter.net = priv->index;
651 msg->msg.filter.option = ESD_ID_ENABLE; /* start with segment 0 */
652 for (i = 0; i < ESD_MAX_ID_SEGMENT; i++)
653 msg->msg.filter.mask[i] = cpu_to_le32(0xffffffff);
654 /* enable 29bit extended IDs */
655 msg->msg.filter.mask[ESD_MAX_ID_SEGMENT] = cpu_to_le32(0x00000001);
656
657 err = esd_usb2_send_msg(dev, msg);
658 if (err)
659 goto out;
660
661 err = esd_usb2_setup_rx_urbs(dev);
662 if (err)
663 goto out;
664
665 priv->can.state = CAN_STATE_ERROR_ACTIVE;
666
667 out:
668 if (err == -ENODEV)
669 netif_device_detach(netdev);
670 if (err)
671 netdev_err(netdev, "couldn't start device: %d\n", err);
672
673 kfree(msg);
674 return err;
675 }
676
unlink_all_urbs(struct esd_usb2 * dev)677 static void unlink_all_urbs(struct esd_usb2 *dev)
678 {
679 struct esd_usb2_net_priv *priv;
680 int i, j;
681
682 usb_kill_anchored_urbs(&dev->rx_submitted);
683
684 for (i = 0; i < MAX_RX_URBS; ++i)
685 usb_free_coherent(dev->udev, RX_BUFFER_SIZE,
686 dev->rxbuf[i], dev->rxbuf_dma[i]);
687
688 for (i = 0; i < dev->net_count; i++) {
689 priv = dev->nets[i];
690 if (priv) {
691 usb_kill_anchored_urbs(&priv->tx_submitted);
692 atomic_set(&priv->active_tx_jobs, 0);
693
694 for (j = 0; j < MAX_TX_URBS; j++)
695 priv->tx_contexts[j].echo_index = MAX_TX_URBS;
696 }
697 }
698 }
699
esd_usb2_open(struct net_device * netdev)700 static int esd_usb2_open(struct net_device *netdev)
701 {
702 struct esd_usb2_net_priv *priv = netdev_priv(netdev);
703 int err;
704
705 /* common open */
706 err = open_candev(netdev);
707 if (err)
708 return err;
709
710 /* finally start device */
711 err = esd_usb2_start(priv);
712 if (err) {
713 netdev_warn(netdev, "couldn't start device: %d\n", err);
714 close_candev(netdev);
715 return err;
716 }
717
718 netif_start_queue(netdev);
719
720 return 0;
721 }
722
esd_usb2_start_xmit(struct sk_buff * skb,struct net_device * netdev)723 static netdev_tx_t esd_usb2_start_xmit(struct sk_buff *skb,
724 struct net_device *netdev)
725 {
726 struct esd_usb2_net_priv *priv = netdev_priv(netdev);
727 struct esd_usb2 *dev = priv->usb2;
728 struct esd_tx_urb_context *context = NULL;
729 struct net_device_stats *stats = &netdev->stats;
730 struct can_frame *cf = (struct can_frame *)skb->data;
731 struct esd_usb2_msg *msg;
732 struct urb *urb;
733 u8 *buf;
734 int i, err;
735 int ret = NETDEV_TX_OK;
736 size_t size = sizeof(struct esd_usb2_msg);
737
738 if (can_dropped_invalid_skb(netdev, skb))
739 return NETDEV_TX_OK;
740
741 /* create a URB, and a buffer for it, and copy the data to the URB */
742 urb = usb_alloc_urb(0, GFP_ATOMIC);
743 if (!urb) {
744 stats->tx_dropped++;
745 dev_kfree_skb(skb);
746 goto nourbmem;
747 }
748
749 buf = usb_alloc_coherent(dev->udev, size, GFP_ATOMIC,
750 &urb->transfer_dma);
751 if (!buf) {
752 netdev_err(netdev, "No memory left for USB buffer\n");
753 stats->tx_dropped++;
754 dev_kfree_skb(skb);
755 goto nobufmem;
756 }
757
758 msg = (struct esd_usb2_msg *)buf;
759
760 msg->msg.hdr.len = 3; /* minimal length */
761 msg->msg.hdr.cmd = CMD_CAN_TX;
762 msg->msg.tx.net = priv->index;
763 msg->msg.tx.dlc = can_get_cc_dlc(cf, priv->can.ctrlmode);
764 msg->msg.tx.id = cpu_to_le32(cf->can_id & CAN_ERR_MASK);
765
766 if (cf->can_id & CAN_RTR_FLAG)
767 msg->msg.tx.dlc |= ESD_RTR;
768
769 if (cf->can_id & CAN_EFF_FLAG)
770 msg->msg.tx.id |= cpu_to_le32(ESD_EXTID);
771
772 for (i = 0; i < cf->len; i++)
773 msg->msg.tx.data[i] = cf->data[i];
774
775 msg->msg.hdr.len += (cf->len + 3) >> 2;
776
777 for (i = 0; i < MAX_TX_URBS; i++) {
778 if (priv->tx_contexts[i].echo_index == MAX_TX_URBS) {
779 context = &priv->tx_contexts[i];
780 break;
781 }
782 }
783
784 /*
785 * This may never happen.
786 */
787 if (!context) {
788 netdev_warn(netdev, "couldn't find free context\n");
789 ret = NETDEV_TX_BUSY;
790 goto releasebuf;
791 }
792
793 context->priv = priv;
794 context->echo_index = i;
795 context->len = cf->len;
796
797 /* hnd must not be 0 - MSB is stripped in txdone handling */
798 msg->msg.tx.hnd = 0x80000000 | i; /* returned in TX done message */
799
800 usb_fill_bulk_urb(urb, dev->udev, usb_sndbulkpipe(dev->udev, 2), buf,
801 msg->msg.hdr.len << 2,
802 esd_usb2_write_bulk_callback, context);
803
804 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
805
806 usb_anchor_urb(urb, &priv->tx_submitted);
807
808 can_put_echo_skb(skb, netdev, context->echo_index, 0);
809
810 atomic_inc(&priv->active_tx_jobs);
811
812 /* Slow down tx path */
813 if (atomic_read(&priv->active_tx_jobs) >= MAX_TX_URBS)
814 netif_stop_queue(netdev);
815
816 err = usb_submit_urb(urb, GFP_ATOMIC);
817 if (err) {
818 can_free_echo_skb(netdev, context->echo_index, NULL);
819
820 atomic_dec(&priv->active_tx_jobs);
821 usb_unanchor_urb(urb);
822
823 stats->tx_dropped++;
824
825 if (err == -ENODEV)
826 netif_device_detach(netdev);
827 else
828 netdev_warn(netdev, "failed tx_urb %d\n", err);
829
830 goto releasebuf;
831 }
832
833 netif_trans_update(netdev);
834
835 /*
836 * Release our reference to this URB, the USB core will eventually free
837 * it entirely.
838 */
839 usb_free_urb(urb);
840
841 return NETDEV_TX_OK;
842
843 releasebuf:
844 usb_free_coherent(dev->udev, size, buf, urb->transfer_dma);
845
846 nobufmem:
847 usb_free_urb(urb);
848
849 nourbmem:
850 return ret;
851 }
852
esd_usb2_close(struct net_device * netdev)853 static int esd_usb2_close(struct net_device *netdev)
854 {
855 struct esd_usb2_net_priv *priv = netdev_priv(netdev);
856 struct esd_usb2_msg *msg;
857 int i;
858
859 msg = kmalloc(sizeof(*msg), GFP_KERNEL);
860 if (!msg)
861 return -ENOMEM;
862
863 /* Disable all IDs (see esd_usb2_start()) */
864 msg->msg.hdr.cmd = CMD_IDADD;
865 msg->msg.hdr.len = 2 + ESD_MAX_ID_SEGMENT;
866 msg->msg.filter.net = priv->index;
867 msg->msg.filter.option = ESD_ID_ENABLE; /* start with segment 0 */
868 for (i = 0; i <= ESD_MAX_ID_SEGMENT; i++)
869 msg->msg.filter.mask[i] = 0;
870 if (esd_usb2_send_msg(priv->usb2, msg) < 0)
871 netdev_err(netdev, "sending idadd message failed\n");
872
873 /* set CAN controller to reset mode */
874 msg->msg.hdr.len = 2;
875 msg->msg.hdr.cmd = CMD_SETBAUD;
876 msg->msg.setbaud.net = priv->index;
877 msg->msg.setbaud.rsvd = 0;
878 msg->msg.setbaud.baud = cpu_to_le32(ESD_USB2_NO_BAUDRATE);
879 if (esd_usb2_send_msg(priv->usb2, msg) < 0)
880 netdev_err(netdev, "sending setbaud message failed\n");
881
882 priv->can.state = CAN_STATE_STOPPED;
883
884 netif_stop_queue(netdev);
885
886 close_candev(netdev);
887
888 kfree(msg);
889
890 return 0;
891 }
892
893 static const struct net_device_ops esd_usb2_netdev_ops = {
894 .ndo_open = esd_usb2_open,
895 .ndo_stop = esd_usb2_close,
896 .ndo_start_xmit = esd_usb2_start_xmit,
897 .ndo_change_mtu = can_change_mtu,
898 };
899
900 static const struct can_bittiming_const esd_usb2_bittiming_const = {
901 .name = "esd_usb2",
902 .tseg1_min = ESD_USB2_TSEG1_MIN,
903 .tseg1_max = ESD_USB2_TSEG1_MAX,
904 .tseg2_min = ESD_USB2_TSEG2_MIN,
905 .tseg2_max = ESD_USB2_TSEG2_MAX,
906 .sjw_max = ESD_USB2_SJW_MAX,
907 .brp_min = ESD_USB2_BRP_MIN,
908 .brp_max = ESD_USB2_BRP_MAX,
909 .brp_inc = ESD_USB2_BRP_INC,
910 };
911
esd_usb2_set_bittiming(struct net_device * netdev)912 static int esd_usb2_set_bittiming(struct net_device *netdev)
913 {
914 struct esd_usb2_net_priv *priv = netdev_priv(netdev);
915 struct can_bittiming *bt = &priv->can.bittiming;
916 struct esd_usb2_msg *msg;
917 int err;
918 u32 canbtr;
919 int sjw_shift;
920
921 canbtr = ESD_USB2_UBR;
922 if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
923 canbtr |= ESD_USB2_LOM;
924
925 canbtr |= (bt->brp - 1) & (ESD_USB2_BRP_MAX - 1);
926
927 if (le16_to_cpu(priv->usb2->udev->descriptor.idProduct) ==
928 USB_CANUSBM_PRODUCT_ID)
929 sjw_shift = ESD_USBM_SJW_SHIFT;
930 else
931 sjw_shift = ESD_USB2_SJW_SHIFT;
932
933 canbtr |= ((bt->sjw - 1) & (ESD_USB2_SJW_MAX - 1))
934 << sjw_shift;
935 canbtr |= ((bt->prop_seg + bt->phase_seg1 - 1)
936 & (ESD_USB2_TSEG1_MAX - 1))
937 << ESD_USB2_TSEG1_SHIFT;
938 canbtr |= ((bt->phase_seg2 - 1) & (ESD_USB2_TSEG2_MAX - 1))
939 << ESD_USB2_TSEG2_SHIFT;
940 if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
941 canbtr |= ESD_USB2_3_SAMPLES;
942
943 msg = kmalloc(sizeof(*msg), GFP_KERNEL);
944 if (!msg)
945 return -ENOMEM;
946
947 msg->msg.hdr.len = 2;
948 msg->msg.hdr.cmd = CMD_SETBAUD;
949 msg->msg.setbaud.net = priv->index;
950 msg->msg.setbaud.rsvd = 0;
951 msg->msg.setbaud.baud = cpu_to_le32(canbtr);
952
953 netdev_info(netdev, "setting BTR=%#x\n", canbtr);
954
955 err = esd_usb2_send_msg(priv->usb2, msg);
956
957 kfree(msg);
958 return err;
959 }
960
esd_usb2_get_berr_counter(const struct net_device * netdev,struct can_berr_counter * bec)961 static int esd_usb2_get_berr_counter(const struct net_device *netdev,
962 struct can_berr_counter *bec)
963 {
964 struct esd_usb2_net_priv *priv = netdev_priv(netdev);
965
966 bec->txerr = priv->bec.txerr;
967 bec->rxerr = priv->bec.rxerr;
968
969 return 0;
970 }
971
esd_usb2_set_mode(struct net_device * netdev,enum can_mode mode)972 static int esd_usb2_set_mode(struct net_device *netdev, enum can_mode mode)
973 {
974 switch (mode) {
975 case CAN_MODE_START:
976 netif_wake_queue(netdev);
977 break;
978
979 default:
980 return -EOPNOTSUPP;
981 }
982
983 return 0;
984 }
985
esd_usb2_probe_one_net(struct usb_interface * intf,int index)986 static int esd_usb2_probe_one_net(struct usb_interface *intf, int index)
987 {
988 struct esd_usb2 *dev = usb_get_intfdata(intf);
989 struct net_device *netdev;
990 struct esd_usb2_net_priv *priv;
991 int err = 0;
992 int i;
993
994 netdev = alloc_candev(sizeof(*priv), MAX_TX_URBS);
995 if (!netdev) {
996 dev_err(&intf->dev, "couldn't alloc candev\n");
997 err = -ENOMEM;
998 goto done;
999 }
1000
1001 priv = netdev_priv(netdev);
1002
1003 init_usb_anchor(&priv->tx_submitted);
1004 atomic_set(&priv->active_tx_jobs, 0);
1005
1006 for (i = 0; i < MAX_TX_URBS; i++)
1007 priv->tx_contexts[i].echo_index = MAX_TX_URBS;
1008
1009 priv->usb2 = dev;
1010 priv->netdev = netdev;
1011 priv->index = index;
1012
1013 priv->can.state = CAN_STATE_STOPPED;
1014 priv->can.ctrlmode_supported = CAN_CTRLMODE_LISTENONLY |
1015 CAN_CTRLMODE_CC_LEN8_DLC;
1016
1017 if (le16_to_cpu(dev->udev->descriptor.idProduct) ==
1018 USB_CANUSBM_PRODUCT_ID)
1019 priv->can.clock.freq = ESD_USBM_CAN_CLOCK;
1020 else {
1021 priv->can.clock.freq = ESD_USB2_CAN_CLOCK;
1022 priv->can.ctrlmode_supported |= CAN_CTRLMODE_3_SAMPLES;
1023 }
1024
1025 priv->can.bittiming_const = &esd_usb2_bittiming_const;
1026 priv->can.do_set_bittiming = esd_usb2_set_bittiming;
1027 priv->can.do_set_mode = esd_usb2_set_mode;
1028 priv->can.do_get_berr_counter = esd_usb2_get_berr_counter;
1029
1030 netdev->flags |= IFF_ECHO; /* we support local echo */
1031
1032 netdev->netdev_ops = &esd_usb2_netdev_ops;
1033
1034 SET_NETDEV_DEV(netdev, &intf->dev);
1035 netdev->dev_id = index;
1036
1037 err = register_candev(netdev);
1038 if (err) {
1039 dev_err(&intf->dev, "couldn't register CAN device: %d\n", err);
1040 free_candev(netdev);
1041 err = -ENOMEM;
1042 goto done;
1043 }
1044
1045 dev->nets[index] = priv;
1046 netdev_info(netdev, "device %s registered\n", netdev->name);
1047
1048 done:
1049 return err;
1050 }
1051
1052 /*
1053 * probe function for new USB2 devices
1054 *
1055 * check version information and number of available
1056 * CAN interfaces
1057 */
esd_usb2_probe(struct usb_interface * intf,const struct usb_device_id * id)1058 static int esd_usb2_probe(struct usb_interface *intf,
1059 const struct usb_device_id *id)
1060 {
1061 struct esd_usb2 *dev;
1062 struct esd_usb2_msg *msg;
1063 int i, err;
1064
1065 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1066 if (!dev) {
1067 err = -ENOMEM;
1068 goto done;
1069 }
1070
1071 dev->udev = interface_to_usbdev(intf);
1072
1073 init_usb_anchor(&dev->rx_submitted);
1074
1075 usb_set_intfdata(intf, dev);
1076
1077 msg = kmalloc(sizeof(*msg), GFP_KERNEL);
1078 if (!msg) {
1079 err = -ENOMEM;
1080 goto free_msg;
1081 }
1082
1083 /* query number of CAN interfaces (nets) */
1084 msg->msg.hdr.cmd = CMD_VERSION;
1085 msg->msg.hdr.len = 2;
1086 msg->msg.version.rsvd = 0;
1087 msg->msg.version.flags = 0;
1088 msg->msg.version.drv_version = 0;
1089
1090 err = esd_usb2_send_msg(dev, msg);
1091 if (err < 0) {
1092 dev_err(&intf->dev, "sending version message failed\n");
1093 goto free_msg;
1094 }
1095
1096 err = esd_usb2_wait_msg(dev, msg);
1097 if (err < 0) {
1098 dev_err(&intf->dev, "no version message answer\n");
1099 goto free_msg;
1100 }
1101
1102 dev->net_count = (int)msg->msg.version_reply.nets;
1103 dev->version = le32_to_cpu(msg->msg.version_reply.version);
1104
1105 if (device_create_file(&intf->dev, &dev_attr_firmware))
1106 dev_err(&intf->dev,
1107 "Couldn't create device file for firmware\n");
1108
1109 if (device_create_file(&intf->dev, &dev_attr_hardware))
1110 dev_err(&intf->dev,
1111 "Couldn't create device file for hardware\n");
1112
1113 if (device_create_file(&intf->dev, &dev_attr_nets))
1114 dev_err(&intf->dev,
1115 "Couldn't create device file for nets\n");
1116
1117 /* do per device probing */
1118 for (i = 0; i < dev->net_count; i++)
1119 esd_usb2_probe_one_net(intf, i);
1120
1121 free_msg:
1122 kfree(msg);
1123 if (err)
1124 kfree(dev);
1125 done:
1126 return err;
1127 }
1128
1129 /*
1130 * called by the usb core when the device is removed from the system
1131 */
esd_usb2_disconnect(struct usb_interface * intf)1132 static void esd_usb2_disconnect(struct usb_interface *intf)
1133 {
1134 struct esd_usb2 *dev = usb_get_intfdata(intf);
1135 struct net_device *netdev;
1136 int i;
1137
1138 device_remove_file(&intf->dev, &dev_attr_firmware);
1139 device_remove_file(&intf->dev, &dev_attr_hardware);
1140 device_remove_file(&intf->dev, &dev_attr_nets);
1141
1142 usb_set_intfdata(intf, NULL);
1143
1144 if (dev) {
1145 for (i = 0; i < dev->net_count; i++) {
1146 if (dev->nets[i]) {
1147 netdev = dev->nets[i]->netdev;
1148 unregister_netdev(netdev);
1149 free_candev(netdev);
1150 }
1151 }
1152 unlink_all_urbs(dev);
1153 kfree(dev);
1154 }
1155 }
1156
1157 /* usb specific object needed to register this driver with the usb subsystem */
1158 static struct usb_driver esd_usb2_driver = {
1159 .name = "esd_usb2",
1160 .probe = esd_usb2_probe,
1161 .disconnect = esd_usb2_disconnect,
1162 .id_table = esd_usb2_table,
1163 };
1164
1165 module_usb_driver(esd_usb2_driver);
1166