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 dlc;
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 cf->data[3] = ecc & SJA1000_ECC_SEG;
282 break;
283 }
284
285 /* Error occurred during transmission? */
286 if (!(ecc & SJA1000_ECC_DIR))
287 cf->data[2] |= CAN_ERR_PROT_TX;
288
289 if (priv->can.state == CAN_STATE_ERROR_WARNING ||
290 priv->can.state == CAN_STATE_ERROR_PASSIVE) {
291 cf->data[1] = (txerr > rxerr) ?
292 CAN_ERR_CRTL_TX_PASSIVE :
293 CAN_ERR_CRTL_RX_PASSIVE;
294 }
295 cf->data[6] = txerr;
296 cf->data[7] = rxerr;
297 }
298
299 priv->bec.txerr = txerr;
300 priv->bec.rxerr = rxerr;
301
302 stats->rx_packets++;
303 stats->rx_bytes += cf->can_dlc;
304 netif_rx(skb);
305 }
306 }
307
esd_usb2_rx_can_msg(struct esd_usb2_net_priv * priv,struct esd_usb2_msg * msg)308 static void esd_usb2_rx_can_msg(struct esd_usb2_net_priv *priv,
309 struct esd_usb2_msg *msg)
310 {
311 struct net_device_stats *stats = &priv->netdev->stats;
312 struct can_frame *cf;
313 struct sk_buff *skb;
314 int i;
315 u32 id;
316
317 if (!netif_device_present(priv->netdev))
318 return;
319
320 id = le32_to_cpu(msg->msg.rx.id);
321
322 if (id & ESD_EVENT) {
323 esd_usb2_rx_event(priv, msg);
324 } else {
325 skb = alloc_can_skb(priv->netdev, &cf);
326 if (skb == NULL) {
327 stats->rx_dropped++;
328 return;
329 }
330
331 cf->can_id = id & ESD_IDMASK;
332 cf->can_dlc = get_can_dlc(msg->msg.rx.dlc & ~ESD_RTR);
333
334 if (id & ESD_EXTID)
335 cf->can_id |= CAN_EFF_FLAG;
336
337 if (msg->msg.rx.dlc & ESD_RTR) {
338 cf->can_id |= CAN_RTR_FLAG;
339 } else {
340 for (i = 0; i < cf->can_dlc; i++)
341 cf->data[i] = msg->msg.rx.data[i];
342 }
343
344 stats->rx_packets++;
345 stats->rx_bytes += cf->can_dlc;
346 netif_rx(skb);
347 }
348
349 return;
350 }
351
esd_usb2_tx_done_msg(struct esd_usb2_net_priv * priv,struct esd_usb2_msg * msg)352 static void esd_usb2_tx_done_msg(struct esd_usb2_net_priv *priv,
353 struct esd_usb2_msg *msg)
354 {
355 struct net_device_stats *stats = &priv->netdev->stats;
356 struct net_device *netdev = priv->netdev;
357 struct esd_tx_urb_context *context;
358
359 if (!netif_device_present(netdev))
360 return;
361
362 context = &priv->tx_contexts[msg->msg.txdone.hnd & (MAX_TX_URBS - 1)];
363
364 if (!msg->msg.txdone.status) {
365 stats->tx_packets++;
366 stats->tx_bytes += context->dlc;
367 can_get_echo_skb(netdev, context->echo_index);
368 } else {
369 stats->tx_errors++;
370 can_free_echo_skb(netdev, context->echo_index);
371 }
372
373 /* Release context */
374 context->echo_index = MAX_TX_URBS;
375 atomic_dec(&priv->active_tx_jobs);
376
377 netif_wake_queue(netdev);
378 }
379
esd_usb2_read_bulk_callback(struct urb * urb)380 static void esd_usb2_read_bulk_callback(struct urb *urb)
381 {
382 struct esd_usb2 *dev = urb->context;
383 int retval;
384 int pos = 0;
385 int i;
386
387 switch (urb->status) {
388 case 0: /* success */
389 break;
390
391 case -ENOENT:
392 case -EPIPE:
393 case -EPROTO:
394 case -ESHUTDOWN:
395 return;
396
397 default:
398 dev_info(dev->udev->dev.parent,
399 "Rx URB aborted (%d)\n", urb->status);
400 goto resubmit_urb;
401 }
402
403 while (pos < urb->actual_length) {
404 struct esd_usb2_msg *msg;
405
406 msg = (struct esd_usb2_msg *)(urb->transfer_buffer + pos);
407
408 switch (msg->msg.hdr.cmd) {
409 case CMD_CAN_RX:
410 if (msg->msg.rx.net >= dev->net_count) {
411 dev_err(dev->udev->dev.parent, "format error\n");
412 break;
413 }
414
415 esd_usb2_rx_can_msg(dev->nets[msg->msg.rx.net], msg);
416 break;
417
418 case CMD_CAN_TX:
419 if (msg->msg.txdone.net >= dev->net_count) {
420 dev_err(dev->udev->dev.parent, "format error\n");
421 break;
422 }
423
424 esd_usb2_tx_done_msg(dev->nets[msg->msg.txdone.net],
425 msg);
426 break;
427 }
428
429 pos += msg->msg.hdr.len << 2;
430
431 if (pos > urb->actual_length) {
432 dev_err(dev->udev->dev.parent, "format error\n");
433 break;
434 }
435 }
436
437 resubmit_urb:
438 usb_fill_bulk_urb(urb, dev->udev, usb_rcvbulkpipe(dev->udev, 1),
439 urb->transfer_buffer, RX_BUFFER_SIZE,
440 esd_usb2_read_bulk_callback, dev);
441
442 retval = usb_submit_urb(urb, GFP_ATOMIC);
443 if (retval == -ENODEV) {
444 for (i = 0; i < dev->net_count; i++) {
445 if (dev->nets[i])
446 netif_device_detach(dev->nets[i]->netdev);
447 }
448 } else if (retval) {
449 dev_err(dev->udev->dev.parent,
450 "failed resubmitting read bulk urb: %d\n", retval);
451 }
452
453 return;
454 }
455
456 /*
457 * callback for bulk IN urb
458 */
esd_usb2_write_bulk_callback(struct urb * urb)459 static void esd_usb2_write_bulk_callback(struct urb *urb)
460 {
461 struct esd_tx_urb_context *context = urb->context;
462 struct esd_usb2_net_priv *priv;
463 struct net_device *netdev;
464 size_t size = sizeof(struct esd_usb2_msg);
465
466 WARN_ON(!context);
467
468 priv = context->priv;
469 netdev = priv->netdev;
470
471 /* free up our allocated buffer */
472 usb_free_coherent(urb->dev, size,
473 urb->transfer_buffer, urb->transfer_dma);
474
475 if (!netif_device_present(netdev))
476 return;
477
478 if (urb->status)
479 netdev_info(netdev, "Tx URB aborted (%d)\n", urb->status);
480
481 netif_trans_update(netdev);
482 }
483
show_firmware(struct device * d,struct device_attribute * attr,char * buf)484 static ssize_t show_firmware(struct device *d,
485 struct device_attribute *attr, char *buf)
486 {
487 struct usb_interface *intf = to_usb_interface(d);
488 struct esd_usb2 *dev = usb_get_intfdata(intf);
489
490 return sprintf(buf, "%d.%d.%d\n",
491 (dev->version >> 12) & 0xf,
492 (dev->version >> 8) & 0xf,
493 dev->version & 0xff);
494 }
495 static DEVICE_ATTR(firmware, 0444, show_firmware, NULL);
496
show_hardware(struct device * d,struct device_attribute * attr,char * buf)497 static ssize_t show_hardware(struct device *d,
498 struct device_attribute *attr, char *buf)
499 {
500 struct usb_interface *intf = to_usb_interface(d);
501 struct esd_usb2 *dev = usb_get_intfdata(intf);
502
503 return sprintf(buf, "%d.%d.%d\n",
504 (dev->version >> 28) & 0xf,
505 (dev->version >> 24) & 0xf,
506 (dev->version >> 16) & 0xff);
507 }
508 static DEVICE_ATTR(hardware, 0444, show_hardware, NULL);
509
show_nets(struct device * d,struct device_attribute * attr,char * buf)510 static ssize_t show_nets(struct device *d,
511 struct device_attribute *attr, char *buf)
512 {
513 struct usb_interface *intf = to_usb_interface(d);
514 struct esd_usb2 *dev = usb_get_intfdata(intf);
515
516 return sprintf(buf, "%d", dev->net_count);
517 }
518 static DEVICE_ATTR(nets, 0444, show_nets, NULL);
519
esd_usb2_send_msg(struct esd_usb2 * dev,struct esd_usb2_msg * msg)520 static int esd_usb2_send_msg(struct esd_usb2 *dev, struct esd_usb2_msg *msg)
521 {
522 int actual_length;
523
524 return usb_bulk_msg(dev->udev,
525 usb_sndbulkpipe(dev->udev, 2),
526 msg,
527 msg->msg.hdr.len << 2,
528 &actual_length,
529 1000);
530 }
531
esd_usb2_wait_msg(struct esd_usb2 * dev,struct esd_usb2_msg * msg)532 static int esd_usb2_wait_msg(struct esd_usb2 *dev,
533 struct esd_usb2_msg *msg)
534 {
535 int actual_length;
536
537 return usb_bulk_msg(dev->udev,
538 usb_rcvbulkpipe(dev->udev, 1),
539 msg,
540 sizeof(*msg),
541 &actual_length,
542 1000);
543 }
544
esd_usb2_setup_rx_urbs(struct esd_usb2 * dev)545 static int esd_usb2_setup_rx_urbs(struct esd_usb2 *dev)
546 {
547 int i, err = 0;
548
549 if (dev->rxinitdone)
550 return 0;
551
552 for (i = 0; i < MAX_RX_URBS; i++) {
553 struct urb *urb = NULL;
554 u8 *buf = NULL;
555 dma_addr_t buf_dma;
556
557 /* create a URB, and a buffer for it */
558 urb = usb_alloc_urb(0, GFP_KERNEL);
559 if (!urb) {
560 err = -ENOMEM;
561 break;
562 }
563
564 buf = usb_alloc_coherent(dev->udev, RX_BUFFER_SIZE, GFP_KERNEL,
565 &buf_dma);
566 if (!buf) {
567 dev_warn(dev->udev->dev.parent,
568 "No memory left for USB buffer\n");
569 err = -ENOMEM;
570 goto freeurb;
571 }
572
573 urb->transfer_dma = buf_dma;
574
575 usb_fill_bulk_urb(urb, dev->udev,
576 usb_rcvbulkpipe(dev->udev, 1),
577 buf, RX_BUFFER_SIZE,
578 esd_usb2_read_bulk_callback, dev);
579 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
580 usb_anchor_urb(urb, &dev->rx_submitted);
581
582 err = usb_submit_urb(urb, GFP_KERNEL);
583 if (err) {
584 usb_unanchor_urb(urb);
585 usb_free_coherent(dev->udev, RX_BUFFER_SIZE, buf,
586 urb->transfer_dma);
587 goto freeurb;
588 }
589
590 dev->rxbuf[i] = buf;
591 dev->rxbuf_dma[i] = buf_dma;
592
593 freeurb:
594 /* Drop reference, USB core will take care of freeing it */
595 usb_free_urb(urb);
596 if (err)
597 break;
598 }
599
600 /* Did we submit any URBs */
601 if (i == 0) {
602 dev_err(dev->udev->dev.parent, "couldn't setup read URBs\n");
603 return err;
604 }
605
606 /* Warn if we've couldn't transmit all the URBs */
607 if (i < MAX_RX_URBS) {
608 dev_warn(dev->udev->dev.parent,
609 "rx performance may be slow\n");
610 }
611
612 dev->rxinitdone = 1;
613 return 0;
614 }
615
616 /*
617 * Start interface
618 */
esd_usb2_start(struct esd_usb2_net_priv * priv)619 static int esd_usb2_start(struct esd_usb2_net_priv *priv)
620 {
621 struct esd_usb2 *dev = priv->usb2;
622 struct net_device *netdev = priv->netdev;
623 struct esd_usb2_msg *msg;
624 int err, i;
625
626 msg = kmalloc(sizeof(*msg), GFP_KERNEL);
627 if (!msg) {
628 err = -ENOMEM;
629 goto out;
630 }
631
632 /*
633 * Enable all IDs
634 * The IDADD message takes up to 64 32 bit bitmasks (2048 bits).
635 * Each bit represents one 11 bit CAN identifier. A set bit
636 * enables reception of the corresponding CAN identifier. A cleared
637 * bit disabled this identifier. An additional bitmask value
638 * following the CAN 2.0A bits is used to enable reception of
639 * extended CAN frames. Only the LSB of this final mask is checked
640 * for the complete 29 bit ID range. The IDADD message also allows
641 * filter configuration for an ID subset. In this case you can add
642 * the number of the starting bitmask (0..64) to the filter.option
643 * field followed by only some bitmasks.
644 */
645 msg->msg.hdr.cmd = CMD_IDADD;
646 msg->msg.hdr.len = 2 + ESD_MAX_ID_SEGMENT;
647 msg->msg.filter.net = priv->index;
648 msg->msg.filter.option = ESD_ID_ENABLE; /* start with segment 0 */
649 for (i = 0; i < ESD_MAX_ID_SEGMENT; i++)
650 msg->msg.filter.mask[i] = cpu_to_le32(0xffffffff);
651 /* enable 29bit extended IDs */
652 msg->msg.filter.mask[ESD_MAX_ID_SEGMENT] = cpu_to_le32(0x00000001);
653
654 err = esd_usb2_send_msg(dev, msg);
655 if (err)
656 goto out;
657
658 err = esd_usb2_setup_rx_urbs(dev);
659 if (err)
660 goto out;
661
662 priv->can.state = CAN_STATE_ERROR_ACTIVE;
663
664 out:
665 if (err == -ENODEV)
666 netif_device_detach(netdev);
667 if (err)
668 netdev_err(netdev, "couldn't start device: %d\n", err);
669
670 kfree(msg);
671 return err;
672 }
673
unlink_all_urbs(struct esd_usb2 * dev)674 static void unlink_all_urbs(struct esd_usb2 *dev)
675 {
676 struct esd_usb2_net_priv *priv;
677 int i, j;
678
679 usb_kill_anchored_urbs(&dev->rx_submitted);
680
681 for (i = 0; i < MAX_RX_URBS; ++i)
682 usb_free_coherent(dev->udev, RX_BUFFER_SIZE,
683 dev->rxbuf[i], dev->rxbuf_dma[i]);
684
685 for (i = 0; i < dev->net_count; i++) {
686 priv = dev->nets[i];
687 if (priv) {
688 usb_kill_anchored_urbs(&priv->tx_submitted);
689 atomic_set(&priv->active_tx_jobs, 0);
690
691 for (j = 0; j < MAX_TX_URBS; j++)
692 priv->tx_contexts[j].echo_index = MAX_TX_URBS;
693 }
694 }
695 }
696
esd_usb2_open(struct net_device * netdev)697 static int esd_usb2_open(struct net_device *netdev)
698 {
699 struct esd_usb2_net_priv *priv = netdev_priv(netdev);
700 int err;
701
702 /* common open */
703 err = open_candev(netdev);
704 if (err)
705 return err;
706
707 /* finally start device */
708 err = esd_usb2_start(priv);
709 if (err) {
710 netdev_warn(netdev, "couldn't start device: %d\n", err);
711 close_candev(netdev);
712 return err;
713 }
714
715 netif_start_queue(netdev);
716
717 return 0;
718 }
719
esd_usb2_start_xmit(struct sk_buff * skb,struct net_device * netdev)720 static netdev_tx_t esd_usb2_start_xmit(struct sk_buff *skb,
721 struct net_device *netdev)
722 {
723 struct esd_usb2_net_priv *priv = netdev_priv(netdev);
724 struct esd_usb2 *dev = priv->usb2;
725 struct esd_tx_urb_context *context = NULL;
726 struct net_device_stats *stats = &netdev->stats;
727 struct can_frame *cf = (struct can_frame *)skb->data;
728 struct esd_usb2_msg *msg;
729 struct urb *urb;
730 u8 *buf;
731 int i, err;
732 int ret = NETDEV_TX_OK;
733 size_t size = sizeof(struct esd_usb2_msg);
734
735 if (can_dropped_invalid_skb(netdev, skb))
736 return NETDEV_TX_OK;
737
738 /* create a URB, and a buffer for it, and copy the data to the URB */
739 urb = usb_alloc_urb(0, GFP_ATOMIC);
740 if (!urb) {
741 stats->tx_dropped++;
742 dev_kfree_skb(skb);
743 goto nourbmem;
744 }
745
746 buf = usb_alloc_coherent(dev->udev, size, GFP_ATOMIC,
747 &urb->transfer_dma);
748 if (!buf) {
749 netdev_err(netdev, "No memory left for USB buffer\n");
750 stats->tx_dropped++;
751 dev_kfree_skb(skb);
752 goto nobufmem;
753 }
754
755 msg = (struct esd_usb2_msg *)buf;
756
757 msg->msg.hdr.len = 3; /* minimal length */
758 msg->msg.hdr.cmd = CMD_CAN_TX;
759 msg->msg.tx.net = priv->index;
760 msg->msg.tx.dlc = cf->can_dlc;
761 msg->msg.tx.id = cpu_to_le32(cf->can_id & CAN_ERR_MASK);
762
763 if (cf->can_id & CAN_RTR_FLAG)
764 msg->msg.tx.dlc |= ESD_RTR;
765
766 if (cf->can_id & CAN_EFF_FLAG)
767 msg->msg.tx.id |= cpu_to_le32(ESD_EXTID);
768
769 for (i = 0; i < cf->can_dlc; i++)
770 msg->msg.tx.data[i] = cf->data[i];
771
772 msg->msg.hdr.len += (cf->can_dlc + 3) >> 2;
773
774 for (i = 0; i < MAX_TX_URBS; i++) {
775 if (priv->tx_contexts[i].echo_index == MAX_TX_URBS) {
776 context = &priv->tx_contexts[i];
777 break;
778 }
779 }
780
781 /*
782 * This may never happen.
783 */
784 if (!context) {
785 netdev_warn(netdev, "couldn't find free context\n");
786 ret = NETDEV_TX_BUSY;
787 goto releasebuf;
788 }
789
790 context->priv = priv;
791 context->echo_index = i;
792 context->dlc = cf->can_dlc;
793
794 /* hnd must not be 0 - MSB is stripped in txdone handling */
795 msg->msg.tx.hnd = 0x80000000 | i; /* returned in TX done message */
796
797 usb_fill_bulk_urb(urb, dev->udev, usb_sndbulkpipe(dev->udev, 2), buf,
798 msg->msg.hdr.len << 2,
799 esd_usb2_write_bulk_callback, context);
800
801 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
802
803 usb_anchor_urb(urb, &priv->tx_submitted);
804
805 can_put_echo_skb(skb, netdev, context->echo_index);
806
807 atomic_inc(&priv->active_tx_jobs);
808
809 /* Slow down tx path */
810 if (atomic_read(&priv->active_tx_jobs) >= MAX_TX_URBS)
811 netif_stop_queue(netdev);
812
813 err = usb_submit_urb(urb, GFP_ATOMIC);
814 if (err) {
815 can_free_echo_skb(netdev, context->echo_index);
816
817 atomic_dec(&priv->active_tx_jobs);
818 usb_unanchor_urb(urb);
819
820 stats->tx_dropped++;
821
822 if (err == -ENODEV)
823 netif_device_detach(netdev);
824 else
825 netdev_warn(netdev, "failed tx_urb %d\n", err);
826
827 goto releasebuf;
828 }
829
830 netif_trans_update(netdev);
831
832 /*
833 * Release our reference to this URB, the USB core will eventually free
834 * it entirely.
835 */
836 usb_free_urb(urb);
837
838 return NETDEV_TX_OK;
839
840 releasebuf:
841 usb_free_coherent(dev->udev, size, buf, urb->transfer_dma);
842
843 nobufmem:
844 usb_free_urb(urb);
845
846 nourbmem:
847 return ret;
848 }
849
esd_usb2_close(struct net_device * netdev)850 static int esd_usb2_close(struct net_device *netdev)
851 {
852 struct esd_usb2_net_priv *priv = netdev_priv(netdev);
853 struct esd_usb2_msg *msg;
854 int i;
855
856 msg = kmalloc(sizeof(*msg), GFP_KERNEL);
857 if (!msg)
858 return -ENOMEM;
859
860 /* Disable all IDs (see esd_usb2_start()) */
861 msg->msg.hdr.cmd = CMD_IDADD;
862 msg->msg.hdr.len = 2 + ESD_MAX_ID_SEGMENT;
863 msg->msg.filter.net = priv->index;
864 msg->msg.filter.option = ESD_ID_ENABLE; /* start with segment 0 */
865 for (i = 0; i <= ESD_MAX_ID_SEGMENT; i++)
866 msg->msg.filter.mask[i] = 0;
867 if (esd_usb2_send_msg(priv->usb2, msg) < 0)
868 netdev_err(netdev, "sending idadd message failed\n");
869
870 /* set CAN controller to reset mode */
871 msg->msg.hdr.len = 2;
872 msg->msg.hdr.cmd = CMD_SETBAUD;
873 msg->msg.setbaud.net = priv->index;
874 msg->msg.setbaud.rsvd = 0;
875 msg->msg.setbaud.baud = cpu_to_le32(ESD_USB2_NO_BAUDRATE);
876 if (esd_usb2_send_msg(priv->usb2, msg) < 0)
877 netdev_err(netdev, "sending setbaud message failed\n");
878
879 priv->can.state = CAN_STATE_STOPPED;
880
881 netif_stop_queue(netdev);
882
883 close_candev(netdev);
884
885 kfree(msg);
886
887 return 0;
888 }
889
890 static const struct net_device_ops esd_usb2_netdev_ops = {
891 .ndo_open = esd_usb2_open,
892 .ndo_stop = esd_usb2_close,
893 .ndo_start_xmit = esd_usb2_start_xmit,
894 .ndo_change_mtu = can_change_mtu,
895 };
896
897 static const struct can_bittiming_const esd_usb2_bittiming_const = {
898 .name = "esd_usb2",
899 .tseg1_min = ESD_USB2_TSEG1_MIN,
900 .tseg1_max = ESD_USB2_TSEG1_MAX,
901 .tseg2_min = ESD_USB2_TSEG2_MIN,
902 .tseg2_max = ESD_USB2_TSEG2_MAX,
903 .sjw_max = ESD_USB2_SJW_MAX,
904 .brp_min = ESD_USB2_BRP_MIN,
905 .brp_max = ESD_USB2_BRP_MAX,
906 .brp_inc = ESD_USB2_BRP_INC,
907 };
908
esd_usb2_set_bittiming(struct net_device * netdev)909 static int esd_usb2_set_bittiming(struct net_device *netdev)
910 {
911 struct esd_usb2_net_priv *priv = netdev_priv(netdev);
912 struct can_bittiming *bt = &priv->can.bittiming;
913 struct esd_usb2_msg *msg;
914 int err;
915 u32 canbtr;
916 int sjw_shift;
917
918 canbtr = ESD_USB2_UBR;
919 if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
920 canbtr |= ESD_USB2_LOM;
921
922 canbtr |= (bt->brp - 1) & (ESD_USB2_BRP_MAX - 1);
923
924 if (le16_to_cpu(priv->usb2->udev->descriptor.idProduct) ==
925 USB_CANUSBM_PRODUCT_ID)
926 sjw_shift = ESD_USBM_SJW_SHIFT;
927 else
928 sjw_shift = ESD_USB2_SJW_SHIFT;
929
930 canbtr |= ((bt->sjw - 1) & (ESD_USB2_SJW_MAX - 1))
931 << sjw_shift;
932 canbtr |= ((bt->prop_seg + bt->phase_seg1 - 1)
933 & (ESD_USB2_TSEG1_MAX - 1))
934 << ESD_USB2_TSEG1_SHIFT;
935 canbtr |= ((bt->phase_seg2 - 1) & (ESD_USB2_TSEG2_MAX - 1))
936 << ESD_USB2_TSEG2_SHIFT;
937 if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
938 canbtr |= ESD_USB2_3_SAMPLES;
939
940 msg = kmalloc(sizeof(*msg), GFP_KERNEL);
941 if (!msg)
942 return -ENOMEM;
943
944 msg->msg.hdr.len = 2;
945 msg->msg.hdr.cmd = CMD_SETBAUD;
946 msg->msg.setbaud.net = priv->index;
947 msg->msg.setbaud.rsvd = 0;
948 msg->msg.setbaud.baud = cpu_to_le32(canbtr);
949
950 netdev_info(netdev, "setting BTR=%#x\n", canbtr);
951
952 err = esd_usb2_send_msg(priv->usb2, msg);
953
954 kfree(msg);
955 return err;
956 }
957
esd_usb2_get_berr_counter(const struct net_device * netdev,struct can_berr_counter * bec)958 static int esd_usb2_get_berr_counter(const struct net_device *netdev,
959 struct can_berr_counter *bec)
960 {
961 struct esd_usb2_net_priv *priv = netdev_priv(netdev);
962
963 bec->txerr = priv->bec.txerr;
964 bec->rxerr = priv->bec.rxerr;
965
966 return 0;
967 }
968
esd_usb2_set_mode(struct net_device * netdev,enum can_mode mode)969 static int esd_usb2_set_mode(struct net_device *netdev, enum can_mode mode)
970 {
971 switch (mode) {
972 case CAN_MODE_START:
973 netif_wake_queue(netdev);
974 break;
975
976 default:
977 return -EOPNOTSUPP;
978 }
979
980 return 0;
981 }
982
esd_usb2_probe_one_net(struct usb_interface * intf,int index)983 static int esd_usb2_probe_one_net(struct usb_interface *intf, int index)
984 {
985 struct esd_usb2 *dev = usb_get_intfdata(intf);
986 struct net_device *netdev;
987 struct esd_usb2_net_priv *priv;
988 int err = 0;
989 int i;
990
991 netdev = alloc_candev(sizeof(*priv), MAX_TX_URBS);
992 if (!netdev) {
993 dev_err(&intf->dev, "couldn't alloc candev\n");
994 err = -ENOMEM;
995 goto done;
996 }
997
998 priv = netdev_priv(netdev);
999
1000 init_usb_anchor(&priv->tx_submitted);
1001 atomic_set(&priv->active_tx_jobs, 0);
1002
1003 for (i = 0; i < MAX_TX_URBS; i++)
1004 priv->tx_contexts[i].echo_index = MAX_TX_URBS;
1005
1006 priv->usb2 = dev;
1007 priv->netdev = netdev;
1008 priv->index = index;
1009
1010 priv->can.state = CAN_STATE_STOPPED;
1011 priv->can.ctrlmode_supported = CAN_CTRLMODE_LISTENONLY;
1012
1013 if (le16_to_cpu(dev->udev->descriptor.idProduct) ==
1014 USB_CANUSBM_PRODUCT_ID)
1015 priv->can.clock.freq = ESD_USBM_CAN_CLOCK;
1016 else {
1017 priv->can.clock.freq = ESD_USB2_CAN_CLOCK;
1018 priv->can.ctrlmode_supported |= CAN_CTRLMODE_3_SAMPLES;
1019 }
1020
1021 priv->can.bittiming_const = &esd_usb2_bittiming_const;
1022 priv->can.do_set_bittiming = esd_usb2_set_bittiming;
1023 priv->can.do_set_mode = esd_usb2_set_mode;
1024 priv->can.do_get_berr_counter = esd_usb2_get_berr_counter;
1025
1026 netdev->flags |= IFF_ECHO; /* we support local echo */
1027
1028 netdev->netdev_ops = &esd_usb2_netdev_ops;
1029
1030 SET_NETDEV_DEV(netdev, &intf->dev);
1031 netdev->dev_id = index;
1032
1033 err = register_candev(netdev);
1034 if (err) {
1035 dev_err(&intf->dev, "couldn't register CAN device: %d\n", err);
1036 free_candev(netdev);
1037 err = -ENOMEM;
1038 goto done;
1039 }
1040
1041 dev->nets[index] = priv;
1042 netdev_info(netdev, "device %s registered\n", netdev->name);
1043
1044 done:
1045 return err;
1046 }
1047
1048 /*
1049 * probe function for new USB2 devices
1050 *
1051 * check version information and number of available
1052 * CAN interfaces
1053 */
esd_usb2_probe(struct usb_interface * intf,const struct usb_device_id * id)1054 static int esd_usb2_probe(struct usb_interface *intf,
1055 const struct usb_device_id *id)
1056 {
1057 struct esd_usb2 *dev;
1058 struct esd_usb2_msg *msg;
1059 int i, err;
1060
1061 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1062 if (!dev) {
1063 err = -ENOMEM;
1064 goto done;
1065 }
1066
1067 dev->udev = interface_to_usbdev(intf);
1068
1069 init_usb_anchor(&dev->rx_submitted);
1070
1071 usb_set_intfdata(intf, dev);
1072
1073 msg = kmalloc(sizeof(*msg), GFP_KERNEL);
1074 if (!msg) {
1075 err = -ENOMEM;
1076 goto free_msg;
1077 }
1078
1079 /* query number of CAN interfaces (nets) */
1080 msg->msg.hdr.cmd = CMD_VERSION;
1081 msg->msg.hdr.len = 2;
1082 msg->msg.version.rsvd = 0;
1083 msg->msg.version.flags = 0;
1084 msg->msg.version.drv_version = 0;
1085
1086 err = esd_usb2_send_msg(dev, msg);
1087 if (err < 0) {
1088 dev_err(&intf->dev, "sending version message failed\n");
1089 goto free_msg;
1090 }
1091
1092 err = esd_usb2_wait_msg(dev, msg);
1093 if (err < 0) {
1094 dev_err(&intf->dev, "no version message answer\n");
1095 goto free_msg;
1096 }
1097
1098 dev->net_count = (int)msg->msg.version_reply.nets;
1099 dev->version = le32_to_cpu(msg->msg.version_reply.version);
1100
1101 if (device_create_file(&intf->dev, &dev_attr_firmware))
1102 dev_err(&intf->dev,
1103 "Couldn't create device file for firmware\n");
1104
1105 if (device_create_file(&intf->dev, &dev_attr_hardware))
1106 dev_err(&intf->dev,
1107 "Couldn't create device file for hardware\n");
1108
1109 if (device_create_file(&intf->dev, &dev_attr_nets))
1110 dev_err(&intf->dev,
1111 "Couldn't create device file for nets\n");
1112
1113 /* do per device probing */
1114 for (i = 0; i < dev->net_count; i++)
1115 esd_usb2_probe_one_net(intf, i);
1116
1117 free_msg:
1118 kfree(msg);
1119 if (err)
1120 kfree(dev);
1121 done:
1122 return err;
1123 }
1124
1125 /*
1126 * called by the usb core when the device is removed from the system
1127 */
esd_usb2_disconnect(struct usb_interface * intf)1128 static void esd_usb2_disconnect(struct usb_interface *intf)
1129 {
1130 struct esd_usb2 *dev = usb_get_intfdata(intf);
1131 struct net_device *netdev;
1132 int i;
1133
1134 device_remove_file(&intf->dev, &dev_attr_firmware);
1135 device_remove_file(&intf->dev, &dev_attr_hardware);
1136 device_remove_file(&intf->dev, &dev_attr_nets);
1137
1138 usb_set_intfdata(intf, NULL);
1139
1140 if (dev) {
1141 for (i = 0; i < dev->net_count; i++) {
1142 if (dev->nets[i]) {
1143 netdev = dev->nets[i]->netdev;
1144 unregister_netdev(netdev);
1145 free_candev(netdev);
1146 }
1147 }
1148 unlink_all_urbs(dev);
1149 kfree(dev);
1150 }
1151 }
1152
1153 /* usb specific object needed to register this driver with the usb subsystem */
1154 static struct usb_driver esd_usb2_driver = {
1155 .name = "esd_usb2",
1156 .probe = esd_usb2_probe,
1157 .disconnect = esd_usb2_disconnect,
1158 .id_table = esd_usb2_table,
1159 };
1160
1161 module_usb_driver(esd_usb2_driver);
1162