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 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->can_dlc;
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 cf->can_dlc = get_can_dlc(msg->msg.rx.dlc & ~ESD_RTR);
335
336 if (id & ESD_EXTID)
337 cf->can_id |= CAN_EFF_FLAG;
338
339 if (msg->msg.rx.dlc & ESD_RTR) {
340 cf->can_id |= CAN_RTR_FLAG;
341 } else {
342 for (i = 0; i < cf->can_dlc; i++)
343 cf->data[i] = msg->msg.rx.data[i];
344 }
345
346 stats->rx_packets++;
347 stats->rx_bytes += cf->can_dlc;
348 netif_rx(skb);
349 }
350
351 return;
352 }
353
esd_usb2_tx_done_msg(struct esd_usb2_net_priv *priv, struct esd_usb2_msg *msg)354 static void esd_usb2_tx_done_msg(struct esd_usb2_net_priv *priv,
355 struct esd_usb2_msg *msg)
356 {
357 struct net_device_stats *stats = &priv->netdev->stats;
358 struct net_device *netdev = priv->netdev;
359 struct esd_tx_urb_context *context;
360
361 if (!netif_device_present(netdev))
362 return;
363
364 context = &priv->tx_contexts[msg->msg.txdone.hnd & (MAX_TX_URBS - 1)];
365
366 if (!msg->msg.txdone.status) {
367 stats->tx_packets++;
368 stats->tx_bytes += context->dlc;
369 can_get_echo_skb(netdev, context->echo_index);
370 } else {
371 stats->tx_errors++;
372 can_free_echo_skb(netdev, context->echo_index);
373 }
374
375 /* Release context */
376 context->echo_index = MAX_TX_URBS;
377 atomic_dec(&priv->active_tx_jobs);
378
379 netif_wake_queue(netdev);
380 }
381
esd_usb2_read_bulk_callback(struct urb *urb)382 static void esd_usb2_read_bulk_callback(struct urb *urb)
383 {
384 struct esd_usb2 *dev = urb->context;
385 int retval;
386 int pos = 0;
387 int i;
388
389 switch (urb->status) {
390 case 0: /* success */
391 break;
392
393 case -ENOENT:
394 case -EPIPE:
395 case -EPROTO:
396 case -ESHUTDOWN:
397 return;
398
399 default:
400 dev_info(dev->udev->dev.parent,
401 "Rx URB aborted (%d)\n", urb->status);
402 goto resubmit_urb;
403 }
404
405 while (pos < urb->actual_length) {
406 struct esd_usb2_msg *msg;
407
408 msg = (struct esd_usb2_msg *)(urb->transfer_buffer + pos);
409
410 switch (msg->msg.hdr.cmd) {
411 case CMD_CAN_RX:
412 if (msg->msg.rx.net >= dev->net_count) {
413 dev_err(dev->udev->dev.parent, "format error\n");
414 break;
415 }
416
417 esd_usb2_rx_can_msg(dev->nets[msg->msg.rx.net], msg);
418 break;
419
420 case CMD_CAN_TX:
421 if (msg->msg.txdone.net >= dev->net_count) {
422 dev_err(dev->udev->dev.parent, "format error\n");
423 break;
424 }
425
426 esd_usb2_tx_done_msg(dev->nets[msg->msg.txdone.net],
427 msg);
428 break;
429 }
430
431 pos += msg->msg.hdr.len << 2;
432
433 if (pos > urb->actual_length) {
434 dev_err(dev->udev->dev.parent, "format error\n");
435 break;
436 }
437 }
438
439 resubmit_urb:
440 usb_fill_bulk_urb(urb, dev->udev, usb_rcvbulkpipe(dev->udev, 1),
441 urb->transfer_buffer, RX_BUFFER_SIZE,
442 esd_usb2_read_bulk_callback, dev);
443
444 retval = usb_submit_urb(urb, GFP_ATOMIC);
445 if (retval == -ENODEV) {
446 for (i = 0; i < dev->net_count; i++) {
447 if (dev->nets[i])
448 netif_device_detach(dev->nets[i]->netdev);
449 }
450 } else if (retval) {
451 dev_err(dev->udev->dev.parent,
452 "failed resubmitting read bulk urb: %d\n", retval);
453 }
454
455 return;
456 }
457
458 /*
459 * callback for bulk IN urb
460 */
esd_usb2_write_bulk_callback(struct urb *urb)461 static void esd_usb2_write_bulk_callback(struct urb *urb)
462 {
463 struct esd_tx_urb_context *context = urb->context;
464 struct esd_usb2_net_priv *priv;
465 struct net_device *netdev;
466 size_t size = sizeof(struct esd_usb2_msg);
467
468 WARN_ON(!context);
469
470 priv = context->priv;
471 netdev = priv->netdev;
472
473 /* free up our allocated buffer */
474 usb_free_coherent(urb->dev, size,
475 urb->transfer_buffer, urb->transfer_dma);
476
477 if (!netif_device_present(netdev))
478 return;
479
480 if (urb->status)
481 netdev_info(netdev, "Tx URB aborted (%d)\n", urb->status);
482
483 netif_trans_update(netdev);
484 }
485
show_firmware(struct device *d, struct device_attribute *attr, char *buf)486 static ssize_t show_firmware(struct device *d,
487 struct device_attribute *attr, char *buf)
488 {
489 struct usb_interface *intf = to_usb_interface(d);
490 struct esd_usb2 *dev = usb_get_intfdata(intf);
491
492 return sprintf(buf, "%d.%d.%d\n",
493 (dev->version >> 12) & 0xf,
494 (dev->version >> 8) & 0xf,
495 dev->version & 0xff);
496 }
497 static DEVICE_ATTR(firmware, 0444, show_firmware, NULL);
498
show_hardware(struct device *d, struct device_attribute *attr, char *buf)499 static ssize_t show_hardware(struct device *d,
500 struct device_attribute *attr, char *buf)
501 {
502 struct usb_interface *intf = to_usb_interface(d);
503 struct esd_usb2 *dev = usb_get_intfdata(intf);
504
505 return sprintf(buf, "%d.%d.%d\n",
506 (dev->version >> 28) & 0xf,
507 (dev->version >> 24) & 0xf,
508 (dev->version >> 16) & 0xff);
509 }
510 static DEVICE_ATTR(hardware, 0444, show_hardware, NULL);
511
show_nets(struct device *d, struct device_attribute *attr, char *buf)512 static ssize_t show_nets(struct device *d,
513 struct device_attribute *attr, char *buf)
514 {
515 struct usb_interface *intf = to_usb_interface(d);
516 struct esd_usb2 *dev = usb_get_intfdata(intf);
517
518 return sprintf(buf, "%d", dev->net_count);
519 }
520 static DEVICE_ATTR(nets, 0444, show_nets, NULL);
521
esd_usb2_send_msg(struct esd_usb2 *dev, struct esd_usb2_msg *msg)522 static int esd_usb2_send_msg(struct esd_usb2 *dev, struct esd_usb2_msg *msg)
523 {
524 int actual_length;
525
526 return usb_bulk_msg(dev->udev,
527 usb_sndbulkpipe(dev->udev, 2),
528 msg,
529 msg->msg.hdr.len << 2,
530 &actual_length,
531 1000);
532 }
533
esd_usb2_wait_msg(struct esd_usb2 *dev, struct esd_usb2_msg *msg)534 static int esd_usb2_wait_msg(struct esd_usb2 *dev,
535 struct esd_usb2_msg *msg)
536 {
537 int actual_length;
538
539 return usb_bulk_msg(dev->udev,
540 usb_rcvbulkpipe(dev->udev, 1),
541 msg,
542 sizeof(*msg),
543 &actual_length,
544 1000);
545 }
546
esd_usb2_setup_rx_urbs(struct esd_usb2 *dev)547 static int esd_usb2_setup_rx_urbs(struct esd_usb2 *dev)
548 {
549 int i, err = 0;
550
551 if (dev->rxinitdone)
552 return 0;
553
554 for (i = 0; i < MAX_RX_URBS; i++) {
555 struct urb *urb = NULL;
556 u8 *buf = NULL;
557 dma_addr_t buf_dma;
558
559 /* create a URB, and a buffer for it */
560 urb = usb_alloc_urb(0, GFP_KERNEL);
561 if (!urb) {
562 err = -ENOMEM;
563 break;
564 }
565
566 buf = usb_alloc_coherent(dev->udev, RX_BUFFER_SIZE, GFP_KERNEL,
567 &buf_dma);
568 if (!buf) {
569 dev_warn(dev->udev->dev.parent,
570 "No memory left for USB buffer\n");
571 err = -ENOMEM;
572 goto freeurb;
573 }
574
575 urb->transfer_dma = buf_dma;
576
577 usb_fill_bulk_urb(urb, dev->udev,
578 usb_rcvbulkpipe(dev->udev, 1),
579 buf, RX_BUFFER_SIZE,
580 esd_usb2_read_bulk_callback, dev);
581 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
582 usb_anchor_urb(urb, &dev->rx_submitted);
583
584 err = usb_submit_urb(urb, GFP_KERNEL);
585 if (err) {
586 usb_unanchor_urb(urb);
587 usb_free_coherent(dev->udev, RX_BUFFER_SIZE, buf,
588 urb->transfer_dma);
589 goto freeurb;
590 }
591
592 dev->rxbuf[i] = buf;
593 dev->rxbuf_dma[i] = buf_dma;
594
595 freeurb:
596 /* Drop reference, USB core will take care of freeing it */
597 usb_free_urb(urb);
598 if (err)
599 break;
600 }
601
602 /* Did we submit any URBs */
603 if (i == 0) {
604 dev_err(dev->udev->dev.parent, "couldn't setup read URBs\n");
605 return err;
606 }
607
608 /* Warn if we've couldn't transmit all the URBs */
609 if (i < MAX_RX_URBS) {
610 dev_warn(dev->udev->dev.parent,
611 "rx performance may be slow\n");
612 }
613
614 dev->rxinitdone = 1;
615 return 0;
616 }
617
618 /*
619 * Start interface
620 */
esd_usb2_start(struct esd_usb2_net_priv *priv)621 static int esd_usb2_start(struct esd_usb2_net_priv *priv)
622 {
623 struct esd_usb2 *dev = priv->usb2;
624 struct net_device *netdev = priv->netdev;
625 struct esd_usb2_msg *msg;
626 int err, i;
627
628 msg = kmalloc(sizeof(*msg), GFP_KERNEL);
629 if (!msg) {
630 err = -ENOMEM;
631 goto out;
632 }
633
634 /*
635 * Enable all IDs
636 * The IDADD message takes up to 64 32 bit bitmasks (2048 bits).
637 * Each bit represents one 11 bit CAN identifier. A set bit
638 * enables reception of the corresponding CAN identifier. A cleared
639 * bit disabled this identifier. An additional bitmask value
640 * following the CAN 2.0A bits is used to enable reception of
641 * extended CAN frames. Only the LSB of this final mask is checked
642 * for the complete 29 bit ID range. The IDADD message also allows
643 * filter configuration for an ID subset. In this case you can add
644 * the number of the starting bitmask (0..64) to the filter.option
645 * field followed by only some bitmasks.
646 */
647 msg->msg.hdr.cmd = CMD_IDADD;
648 msg->msg.hdr.len = 2 + ESD_MAX_ID_SEGMENT;
649 msg->msg.filter.net = priv->index;
650 msg->msg.filter.option = ESD_ID_ENABLE; /* start with segment 0 */
651 for (i = 0; i < ESD_MAX_ID_SEGMENT; i++)
652 msg->msg.filter.mask[i] = cpu_to_le32(0xffffffff);
653 /* enable 29bit extended IDs */
654 msg->msg.filter.mask[ESD_MAX_ID_SEGMENT] = cpu_to_le32(0x00000001);
655
656 err = esd_usb2_send_msg(dev, msg);
657 if (err)
658 goto out;
659
660 err = esd_usb2_setup_rx_urbs(dev);
661 if (err)
662 goto out;
663
664 priv->can.state = CAN_STATE_ERROR_ACTIVE;
665
666 out:
667 if (err == -ENODEV)
668 netif_device_detach(netdev);
669 if (err)
670 netdev_err(netdev, "couldn't start device: %d\n", err);
671
672 kfree(msg);
673 return err;
674 }
675
unlink_all_urbs(struct esd_usb2 *dev)676 static void unlink_all_urbs(struct esd_usb2 *dev)
677 {
678 struct esd_usb2_net_priv *priv;
679 int i, j;
680
681 usb_kill_anchored_urbs(&dev->rx_submitted);
682
683 for (i = 0; i < MAX_RX_URBS; ++i)
684 usb_free_coherent(dev->udev, RX_BUFFER_SIZE,
685 dev->rxbuf[i], dev->rxbuf_dma[i]);
686
687 for (i = 0; i < dev->net_count; i++) {
688 priv = dev->nets[i];
689 if (priv) {
690 usb_kill_anchored_urbs(&priv->tx_submitted);
691 atomic_set(&priv->active_tx_jobs, 0);
692
693 for (j = 0; j < MAX_TX_URBS; j++)
694 priv->tx_contexts[j].echo_index = MAX_TX_URBS;
695 }
696 }
697 }
698
esd_usb2_open(struct net_device *netdev)699 static int esd_usb2_open(struct net_device *netdev)
700 {
701 struct esd_usb2_net_priv *priv = netdev_priv(netdev);
702 int err;
703
704 /* common open */
705 err = open_candev(netdev);
706 if (err)
707 return err;
708
709 /* finally start device */
710 err = esd_usb2_start(priv);
711 if (err) {
712 netdev_warn(netdev, "couldn't start device: %d\n", err);
713 close_candev(netdev);
714 return err;
715 }
716
717 netif_start_queue(netdev);
718
719 return 0;
720 }
721
esd_usb2_start_xmit(struct sk_buff *skb, struct net_device *netdev)722 static netdev_tx_t esd_usb2_start_xmit(struct sk_buff *skb,
723 struct net_device *netdev)
724 {
725 struct esd_usb2_net_priv *priv = netdev_priv(netdev);
726 struct esd_usb2 *dev = priv->usb2;
727 struct esd_tx_urb_context *context = NULL;
728 struct net_device_stats *stats = &netdev->stats;
729 struct can_frame *cf = (struct can_frame *)skb->data;
730 struct esd_usb2_msg *msg;
731 struct urb *urb;
732 u8 *buf;
733 int i, err;
734 int ret = NETDEV_TX_OK;
735 size_t size = sizeof(struct esd_usb2_msg);
736
737 if (can_dropped_invalid_skb(netdev, skb))
738 return NETDEV_TX_OK;
739
740 /* create a URB, and a buffer for it, and copy the data to the URB */
741 urb = usb_alloc_urb(0, GFP_ATOMIC);
742 if (!urb) {
743 stats->tx_dropped++;
744 dev_kfree_skb(skb);
745 goto nourbmem;
746 }
747
748 buf = usb_alloc_coherent(dev->udev, size, GFP_ATOMIC,
749 &urb->transfer_dma);
750 if (!buf) {
751 netdev_err(netdev, "No memory left for USB buffer\n");
752 stats->tx_dropped++;
753 dev_kfree_skb(skb);
754 goto nobufmem;
755 }
756
757 msg = (struct esd_usb2_msg *)buf;
758
759 msg->msg.hdr.len = 3; /* minimal length */
760 msg->msg.hdr.cmd = CMD_CAN_TX;
761 msg->msg.tx.net = priv->index;
762 msg->msg.tx.dlc = cf->can_dlc;
763 msg->msg.tx.id = cpu_to_le32(cf->can_id & CAN_ERR_MASK);
764
765 if (cf->can_id & CAN_RTR_FLAG)
766 msg->msg.tx.dlc |= ESD_RTR;
767
768 if (cf->can_id & CAN_EFF_FLAG)
769 msg->msg.tx.id |= cpu_to_le32(ESD_EXTID);
770
771 for (i = 0; i < cf->can_dlc; i++)
772 msg->msg.tx.data[i] = cf->data[i];
773
774 msg->msg.hdr.len += (cf->can_dlc + 3) >> 2;
775
776 for (i = 0; i < MAX_TX_URBS; i++) {
777 if (priv->tx_contexts[i].echo_index == MAX_TX_URBS) {
778 context = &priv->tx_contexts[i];
779 break;
780 }
781 }
782
783 /*
784 * This may never happen.
785 */
786 if (!context) {
787 netdev_warn(netdev, "couldn't find free context\n");
788 ret = NETDEV_TX_BUSY;
789 goto releasebuf;
790 }
791
792 context->priv = priv;
793 context->echo_index = i;
794 context->dlc = cf->can_dlc;
795
796 /* hnd must not be 0 - MSB is stripped in txdone handling */
797 msg->msg.tx.hnd = 0x80000000 | i; /* returned in TX done message */
798
799 usb_fill_bulk_urb(urb, dev->udev, usb_sndbulkpipe(dev->udev, 2), buf,
800 msg->msg.hdr.len << 2,
801 esd_usb2_write_bulk_callback, context);
802
803 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
804
805 usb_anchor_urb(urb, &priv->tx_submitted);
806
807 can_put_echo_skb(skb, netdev, context->echo_index);
808
809 atomic_inc(&priv->active_tx_jobs);
810
811 /* Slow down tx path */
812 if (atomic_read(&priv->active_tx_jobs) >= MAX_TX_URBS)
813 netif_stop_queue(netdev);
814
815 err = usb_submit_urb(urb, GFP_ATOMIC);
816 if (err) {
817 can_free_echo_skb(netdev, context->echo_index);
818
819 atomic_dec(&priv->active_tx_jobs);
820 usb_unanchor_urb(urb);
821
822 stats->tx_dropped++;
823
824 if (err == -ENODEV)
825 netif_device_detach(netdev);
826 else
827 netdev_warn(netdev, "failed tx_urb %d\n", err);
828
829 goto releasebuf;
830 }
831
832 netif_trans_update(netdev);
833
834 /*
835 * Release our reference to this URB, the USB core will eventually free
836 * it entirely.
837 */
838 usb_free_urb(urb);
839
840 return NETDEV_TX_OK;
841
842 releasebuf:
843 usb_free_coherent(dev->udev, size, buf, urb->transfer_dma);
844
845 nobufmem:
846 usb_free_urb(urb);
847
848 nourbmem:
849 return ret;
850 }
851
esd_usb2_close(struct net_device *netdev)852 static int esd_usb2_close(struct net_device *netdev)
853 {
854 struct esd_usb2_net_priv *priv = netdev_priv(netdev);
855 struct esd_usb2_msg *msg;
856 int i;
857
858 msg = kmalloc(sizeof(*msg), GFP_KERNEL);
859 if (!msg)
860 return -ENOMEM;
861
862 /* Disable all IDs (see esd_usb2_start()) */
863 msg->msg.hdr.cmd = CMD_IDADD;
864 msg->msg.hdr.len = 2 + ESD_MAX_ID_SEGMENT;
865 msg->msg.filter.net = priv->index;
866 msg->msg.filter.option = ESD_ID_ENABLE; /* start with segment 0 */
867 for (i = 0; i <= ESD_MAX_ID_SEGMENT; i++)
868 msg->msg.filter.mask[i] = 0;
869 if (esd_usb2_send_msg(priv->usb2, msg) < 0)
870 netdev_err(netdev, "sending idadd message failed\n");
871
872 /* set CAN controller to reset mode */
873 msg->msg.hdr.len = 2;
874 msg->msg.hdr.cmd = CMD_SETBAUD;
875 msg->msg.setbaud.net = priv->index;
876 msg->msg.setbaud.rsvd = 0;
877 msg->msg.setbaud.baud = cpu_to_le32(ESD_USB2_NO_BAUDRATE);
878 if (esd_usb2_send_msg(priv->usb2, msg) < 0)
879 netdev_err(netdev, "sending setbaud message failed\n");
880
881 priv->can.state = CAN_STATE_STOPPED;
882
883 netif_stop_queue(netdev);
884
885 close_candev(netdev);
886
887 kfree(msg);
888
889 return 0;
890 }
891
892 static const struct net_device_ops esd_usb2_netdev_ops = {
893 .ndo_open = esd_usb2_open,
894 .ndo_stop = esd_usb2_close,
895 .ndo_start_xmit = esd_usb2_start_xmit,
896 .ndo_change_mtu = can_change_mtu,
897 };
898
899 static const struct can_bittiming_const esd_usb2_bittiming_const = {
900 .name = "esd_usb2",
901 .tseg1_min = ESD_USB2_TSEG1_MIN,
902 .tseg1_max = ESD_USB2_TSEG1_MAX,
903 .tseg2_min = ESD_USB2_TSEG2_MIN,
904 .tseg2_max = ESD_USB2_TSEG2_MAX,
905 .sjw_max = ESD_USB2_SJW_MAX,
906 .brp_min = ESD_USB2_BRP_MIN,
907 .brp_max = ESD_USB2_BRP_MAX,
908 .brp_inc = ESD_USB2_BRP_INC,
909 };
910
esd_usb2_set_bittiming(struct net_device *netdev)911 static int esd_usb2_set_bittiming(struct net_device *netdev)
912 {
913 struct esd_usb2_net_priv *priv = netdev_priv(netdev);
914 struct can_bittiming *bt = &priv->can.bittiming;
915 struct esd_usb2_msg *msg;
916 int err;
917 u32 canbtr;
918 int sjw_shift;
919
920 canbtr = ESD_USB2_UBR;
921 if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
922 canbtr |= ESD_USB2_LOM;
923
924 canbtr |= (bt->brp - 1) & (ESD_USB2_BRP_MAX - 1);
925
926 if (le16_to_cpu(priv->usb2->udev->descriptor.idProduct) ==
927 USB_CANUSBM_PRODUCT_ID)
928 sjw_shift = ESD_USBM_SJW_SHIFT;
929 else
930 sjw_shift = ESD_USB2_SJW_SHIFT;
931
932 canbtr |= ((bt->sjw - 1) & (ESD_USB2_SJW_MAX - 1))
933 << sjw_shift;
934 canbtr |= ((bt->prop_seg + bt->phase_seg1 - 1)
935 & (ESD_USB2_TSEG1_MAX - 1))
936 << ESD_USB2_TSEG1_SHIFT;
937 canbtr |= ((bt->phase_seg2 - 1) & (ESD_USB2_TSEG2_MAX - 1))
938 << ESD_USB2_TSEG2_SHIFT;
939 if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
940 canbtr |= ESD_USB2_3_SAMPLES;
941
942 msg = kmalloc(sizeof(*msg), GFP_KERNEL);
943 if (!msg)
944 return -ENOMEM;
945
946 msg->msg.hdr.len = 2;
947 msg->msg.hdr.cmd = CMD_SETBAUD;
948 msg->msg.setbaud.net = priv->index;
949 msg->msg.setbaud.rsvd = 0;
950 msg->msg.setbaud.baud = cpu_to_le32(canbtr);
951
952 netdev_info(netdev, "setting BTR=%#x\n", canbtr);
953
954 err = esd_usb2_send_msg(priv->usb2, msg);
955
956 kfree(msg);
957 return err;
958 }
959
esd_usb2_get_berr_counter(const struct net_device *netdev, struct can_berr_counter *bec)960 static int esd_usb2_get_berr_counter(const struct net_device *netdev,
961 struct can_berr_counter *bec)
962 {
963 struct esd_usb2_net_priv *priv = netdev_priv(netdev);
964
965 bec->txerr = priv->bec.txerr;
966 bec->rxerr = priv->bec.rxerr;
967
968 return 0;
969 }
970
esd_usb2_set_mode(struct net_device *netdev, enum can_mode mode)971 static int esd_usb2_set_mode(struct net_device *netdev, enum can_mode mode)
972 {
973 switch (mode) {
974 case CAN_MODE_START:
975 netif_wake_queue(netdev);
976 break;
977
978 default:
979 return -EOPNOTSUPP;
980 }
981
982 return 0;
983 }
984
esd_usb2_probe_one_net(struct usb_interface *intf, int index)985 static int esd_usb2_probe_one_net(struct usb_interface *intf, int index)
986 {
987 struct esd_usb2 *dev = usb_get_intfdata(intf);
988 struct net_device *netdev;
989 struct esd_usb2_net_priv *priv;
990 int err = 0;
991 int i;
992
993 netdev = alloc_candev(sizeof(*priv), MAX_TX_URBS);
994 if (!netdev) {
995 dev_err(&intf->dev, "couldn't alloc candev\n");
996 err = -ENOMEM;
997 goto done;
998 }
999
1000 priv = netdev_priv(netdev);
1001
1002 init_usb_anchor(&priv->tx_submitted);
1003 atomic_set(&priv->active_tx_jobs, 0);
1004
1005 for (i = 0; i < MAX_TX_URBS; i++)
1006 priv->tx_contexts[i].echo_index = MAX_TX_URBS;
1007
1008 priv->usb2 = dev;
1009 priv->netdev = netdev;
1010 priv->index = index;
1011
1012 priv->can.state = CAN_STATE_STOPPED;
1013 priv->can.ctrlmode_supported = CAN_CTRLMODE_LISTENONLY;
1014
1015 if (le16_to_cpu(dev->udev->descriptor.idProduct) ==
1016 USB_CANUSBM_PRODUCT_ID)
1017 priv->can.clock.freq = ESD_USBM_CAN_CLOCK;
1018 else {
1019 priv->can.clock.freq = ESD_USB2_CAN_CLOCK;
1020 priv->can.ctrlmode_supported |= CAN_CTRLMODE_3_SAMPLES;
1021 }
1022
1023 priv->can.bittiming_const = &esd_usb2_bittiming_const;
1024 priv->can.do_set_bittiming = esd_usb2_set_bittiming;
1025 priv->can.do_set_mode = esd_usb2_set_mode;
1026 priv->can.do_get_berr_counter = esd_usb2_get_berr_counter;
1027
1028 netdev->flags |= IFF_ECHO; /* we support local echo */
1029
1030 netdev->netdev_ops = &esd_usb2_netdev_ops;
1031
1032 SET_NETDEV_DEV(netdev, &intf->dev);
1033 netdev->dev_id = index;
1034
1035 err = register_candev(netdev);
1036 if (err) {
1037 dev_err(&intf->dev, "couldn't register CAN device: %d\n", err);
1038 free_candev(netdev);
1039 err = -ENOMEM;
1040 goto done;
1041 }
1042
1043 dev->nets[index] = priv;
1044 netdev_info(netdev, "device %s registered\n", netdev->name);
1045
1046 done:
1047 return err;
1048 }
1049
1050 /*
1051 * probe function for new USB2 devices
1052 *
1053 * check version information and number of available
1054 * CAN interfaces
1055 */
esd_usb2_probe(struct usb_interface *intf, const struct usb_device_id *id)1056 static int esd_usb2_probe(struct usb_interface *intf,
1057 const struct usb_device_id *id)
1058 {
1059 struct esd_usb2 *dev;
1060 struct esd_usb2_msg *msg;
1061 int i, err;
1062
1063 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1064 if (!dev) {
1065 err = -ENOMEM;
1066 goto done;
1067 }
1068
1069 dev->udev = interface_to_usbdev(intf);
1070
1071 init_usb_anchor(&dev->rx_submitted);
1072
1073 usb_set_intfdata(intf, dev);
1074
1075 msg = kmalloc(sizeof(*msg), GFP_KERNEL);
1076 if (!msg) {
1077 err = -ENOMEM;
1078 goto free_msg;
1079 }
1080
1081 /* query number of CAN interfaces (nets) */
1082 msg->msg.hdr.cmd = CMD_VERSION;
1083 msg->msg.hdr.len = 2;
1084 msg->msg.version.rsvd = 0;
1085 msg->msg.version.flags = 0;
1086 msg->msg.version.drv_version = 0;
1087
1088 err = esd_usb2_send_msg(dev, msg);
1089 if (err < 0) {
1090 dev_err(&intf->dev, "sending version message failed\n");
1091 goto free_msg;
1092 }
1093
1094 err = esd_usb2_wait_msg(dev, msg);
1095 if (err < 0) {
1096 dev_err(&intf->dev, "no version message answer\n");
1097 goto free_msg;
1098 }
1099
1100 dev->net_count = (int)msg->msg.version_reply.nets;
1101 dev->version = le32_to_cpu(msg->msg.version_reply.version);
1102
1103 if (device_create_file(&intf->dev, &dev_attr_firmware))
1104 dev_err(&intf->dev,
1105 "Couldn't create device file for firmware\n");
1106
1107 if (device_create_file(&intf->dev, &dev_attr_hardware))
1108 dev_err(&intf->dev,
1109 "Couldn't create device file for hardware\n");
1110
1111 if (device_create_file(&intf->dev, &dev_attr_nets))
1112 dev_err(&intf->dev,
1113 "Couldn't create device file for nets\n");
1114
1115 /* do per device probing */
1116 for (i = 0; i < dev->net_count; i++)
1117 esd_usb2_probe_one_net(intf, i);
1118
1119 free_msg:
1120 kfree(msg);
1121 if (err)
1122 kfree(dev);
1123 done:
1124 return err;
1125 }
1126
1127 /*
1128 * called by the usb core when the device is removed from the system
1129 */
esd_usb2_disconnect(struct usb_interface *intf)1130 static void esd_usb2_disconnect(struct usb_interface *intf)
1131 {
1132 struct esd_usb2 *dev = usb_get_intfdata(intf);
1133 struct net_device *netdev;
1134 int i;
1135
1136 device_remove_file(&intf->dev, &dev_attr_firmware);
1137 device_remove_file(&intf->dev, &dev_attr_hardware);
1138 device_remove_file(&intf->dev, &dev_attr_nets);
1139
1140 usb_set_intfdata(intf, NULL);
1141
1142 if (dev) {
1143 for (i = 0; i < dev->net_count; i++) {
1144 if (dev->nets[i]) {
1145 netdev = dev->nets[i]->netdev;
1146 unregister_netdev(netdev);
1147 free_candev(netdev);
1148 }
1149 }
1150 unlink_all_urbs(dev);
1151 kfree(dev);
1152 }
1153 }
1154
1155 /* usb specific object needed to register this driver with the usb subsystem */
1156 static struct usb_driver esd_usb2_driver = {
1157 .name = "esd_usb2",
1158 .probe = esd_usb2_probe,
1159 .disconnect = esd_usb2_disconnect,
1160 .id_table = esd_usb2_table,
1161 };
1162
1163 module_usb_driver(esd_usb2_driver);
1164