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Linux 3.18.86
[linux/fpc-iii.git] / drivers / net / can / usb / ems_usb.c
blob5c9f06cc35cce6efd6b35b05410a82d208ce0f68
1 /*
2 * CAN driver for EMS Dr. Thomas Wuensche CPC-USB/ARM7
3 *
4 * Copyright (C) 2004-2009 EMS Dr. Thomas Wuensche
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License as published
8 * by the Free Software Foundation; version 2 of the License.
9 *
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License along
16 * with this program; if not, write to the Free Software Foundation, Inc.,
17 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
18 */
19 #include <linux/signal.h>
20 #include <linux/slab.h>
21 #include <linux/module.h>
22 #include <linux/netdevice.h>
23 #include <linux/usb.h>
24
25 #include <linux/can.h>
26 #include <linux/can/dev.h>
27 #include <linux/can/error.h>
28
29 MODULE_AUTHOR("Sebastian Haas <haas@ems-wuensche.com>");
30 MODULE_DESCRIPTION("CAN driver for EMS Dr. Thomas Wuensche CAN/USB interfaces");
31 MODULE_LICENSE("GPL v2");
32
33 /* Control-Values for CPC_Control() Command Subject Selection */
34 #define CONTR_CAN_MESSAGE 0x04
35 #define CONTR_CAN_STATE 0x0C
36 #define CONTR_BUS_ERROR 0x1C
37
38 /* Control Command Actions */
39 #define CONTR_CONT_OFF 0
40 #define CONTR_CONT_ON 1
41 #define CONTR_ONCE 2
42
43 /* Messages from CPC to PC */
44 #define CPC_MSG_TYPE_CAN_FRAME 1 /* CAN data frame */
45 #define CPC_MSG_TYPE_RTR_FRAME 8 /* CAN remote frame */
46 #define CPC_MSG_TYPE_CAN_PARAMS 12 /* Actual CAN parameters */
47 #define CPC_MSG_TYPE_CAN_STATE 14 /* CAN state message */
48 #define CPC_MSG_TYPE_EXT_CAN_FRAME 16 /* Extended CAN data frame */
49 #define CPC_MSG_TYPE_EXT_RTR_FRAME 17 /* Extended remote frame */
50 #define CPC_MSG_TYPE_CONTROL 19 /* change interface behavior */
51 #define CPC_MSG_TYPE_CONFIRM 20 /* command processed confirmation */
52 #define CPC_MSG_TYPE_OVERRUN 21 /* overrun events */
53 #define CPC_MSG_TYPE_CAN_FRAME_ERROR 23 /* detected bus errors */
54 #define CPC_MSG_TYPE_ERR_COUNTER 25 /* RX/TX error counter */
55
56 /* Messages from the PC to the CPC interface */
57 #define CPC_CMD_TYPE_CAN_FRAME 1 /* CAN data frame */
58 #define CPC_CMD_TYPE_CONTROL 3 /* control of interface behavior */
59 #define CPC_CMD_TYPE_CAN_PARAMS 6 /* set CAN parameters */
60 #define CPC_CMD_TYPE_RTR_FRAME 13 /* CAN remote frame */
61 #define CPC_CMD_TYPE_CAN_STATE 14 /* CAN state message */
62 #define CPC_CMD_TYPE_EXT_CAN_FRAME 15 /* Extended CAN data frame */
63 #define CPC_CMD_TYPE_EXT_RTR_FRAME 16 /* Extended CAN remote frame */
64 #define CPC_CMD_TYPE_CAN_EXIT 200 /* exit the CAN */
65
66 #define CPC_CMD_TYPE_INQ_ERR_COUNTER 25 /* request the CAN error counters */
67 #define CPC_CMD_TYPE_CLEAR_MSG_QUEUE 8 /* clear CPC_MSG queue */
68 #define CPC_CMD_TYPE_CLEAR_CMD_QUEUE 28 /* clear CPC_CMD queue */
69
70 #define CPC_CC_TYPE_SJA1000 2 /* Philips basic CAN controller */
71
72 #define CPC_CAN_ECODE_ERRFRAME 0x01 /* Ecode type */
73
74 /* Overrun types */
75 #define CPC_OVR_EVENT_CAN 0x01
76 #define CPC_OVR_EVENT_CANSTATE 0x02
77 #define CPC_OVR_EVENT_BUSERROR 0x04
78
79 /*
80 * If the CAN controller lost a message we indicate it with the highest bit
81 * set in the count field.
82 */
83 #define CPC_OVR_HW 0x80
84
85 /* Size of the "struct ems_cpc_msg" without the union */
86 #define CPC_MSG_HEADER_LEN 11
87 #define CPC_CAN_MSG_MIN_SIZE 5
88
89 /* Define these values to match your devices */
90 #define USB_CPCUSB_VENDOR_ID 0x12D6
91
92 #define USB_CPCUSB_ARM7_PRODUCT_ID 0x0444
93
94 /* Mode register NXP LPC2119/SJA1000 CAN Controller */
95 #define SJA1000_MOD_NORMAL 0x00
96 #define SJA1000_MOD_RM 0x01
97
98 /* ECC register NXP LPC2119/SJA1000 CAN Controller */
99 #define SJA1000_ECC_SEG 0x1F
100 #define SJA1000_ECC_DIR 0x20
101 #define SJA1000_ECC_ERR 0x06
102 #define SJA1000_ECC_BIT 0x00
103 #define SJA1000_ECC_FORM 0x40
104 #define SJA1000_ECC_STUFF 0x80
105 #define SJA1000_ECC_MASK 0xc0
106
107 /* Status register content */
108 #define SJA1000_SR_BS 0x80
109 #define SJA1000_SR_ES 0x40
110
111 #define SJA1000_DEFAULT_OUTPUT_CONTROL 0xDA
112
113 /*
114 * The device actually uses a 16MHz clock to generate the CAN clock
115 * but it expects SJA1000 bit settings based on 8MHz (is internally
116 * converted).
117 */
118 #define EMS_USB_ARM7_CLOCK 8000000
119
120 #define CPC_TX_QUEUE_TRIGGER_LOW 25
121 #define CPC_TX_QUEUE_TRIGGER_HIGH 35
122
123 /*
124 * CAN-Message representation in a CPC_MSG. Message object type is
125 * CPC_MSG_TYPE_CAN_FRAME or CPC_MSG_TYPE_RTR_FRAME or
126 * CPC_MSG_TYPE_EXT_CAN_FRAME or CPC_MSG_TYPE_EXT_RTR_FRAME.
127 */
128 struct cpc_can_msg {
129 u32 id;
130 u8 length;
131 u8 msg[8];
132 };
133
134 /* Representation of the CAN parameters for the SJA1000 controller */
135 struct cpc_sja1000_params {
136 u8 mode;
137 u8 acc_code0;
138 u8 acc_code1;
139 u8 acc_code2;
140 u8 acc_code3;
141 u8 acc_mask0;
142 u8 acc_mask1;
143 u8 acc_mask2;
144 u8 acc_mask3;
145 u8 btr0;
146 u8 btr1;
147 u8 outp_contr;
148 };
149
150 /* CAN params message representation */
151 struct cpc_can_params {
152 u8 cc_type;
153
154 /* Will support M16C CAN controller in the future */
155 union {
156 struct cpc_sja1000_params sja1000;
157 } cc_params;
158 };
159
160 /* Structure for confirmed message handling */
161 struct cpc_confirm {
162 u8 error; /* error code */
163 };
164
165 /* Structure for overrun conditions */
166 struct cpc_overrun {
167 u8 event;
168 u8 count;
169 };
170
171 /* SJA1000 CAN errors (compatible to NXP LPC2119) */
172 struct cpc_sja1000_can_error {
173 u8 ecc;
174 u8 rxerr;
175 u8 txerr;
176 };
177
178 /* structure for CAN error conditions */
179 struct cpc_can_error {
180 u8 ecode;
181
182 struct {
183 u8 cc_type;
184
185 /* Other controllers may also provide error code capture regs */
186 union {
187 struct cpc_sja1000_can_error sja1000;
188 } regs;
189 } cc;
190 };
191
192 /*
193 * Structure containing RX/TX error counter. This structure is used to request
194 * the values of the CAN controllers TX and RX error counter.
195 */
196 struct cpc_can_err_counter {
197 u8 rx;
198 u8 tx;
199 };
200
201 /* Main message type used between library and application */
202 struct __packed ems_cpc_msg {
203 u8 type; /* type of message */
204 u8 length; /* length of data within union 'msg' */
205 u8 msgid; /* confirmation handle */
206 u32 ts_sec; /* timestamp in seconds */
207 u32 ts_nsec; /* timestamp in nano seconds */
208
209 union {
210 u8 generic[64];
211 struct cpc_can_msg can_msg;
212 struct cpc_can_params can_params;
213 struct cpc_confirm confirmation;
214 struct cpc_overrun overrun;
215 struct cpc_can_error error;
216 struct cpc_can_err_counter err_counter;
217 u8 can_state;
218 } msg;
219 };
220
221 /*
222 * Table of devices that work with this driver
223 * NOTE: This driver supports only CPC-USB/ARM7 (LPC2119) yet.
224 */
225 static struct usb_device_id ems_usb_table[] = {
226 {USB_DEVICE(USB_CPCUSB_VENDOR_ID, USB_CPCUSB_ARM7_PRODUCT_ID)},
227 {} /* Terminating entry */
228 };
229
230 MODULE_DEVICE_TABLE(usb, ems_usb_table);
231
232 #define RX_BUFFER_SIZE 64
233 #define CPC_HEADER_SIZE 4
234 #define INTR_IN_BUFFER_SIZE 4
235
236 #define MAX_RX_URBS 10
237 #define MAX_TX_URBS 10
238
239 struct ems_usb;
240
241 struct ems_tx_urb_context {
242 struct ems_usb *dev;
243
244 u32 echo_index;
245 u8 dlc;
246 };
247
248 struct ems_usb {
249 struct can_priv can; /* must be the first member */
250
251 struct sk_buff *echo_skb[MAX_TX_URBS];
252
253 struct usb_device *udev;
254 struct net_device *netdev;
255
256 atomic_t active_tx_urbs;
257 struct usb_anchor tx_submitted;
258 struct ems_tx_urb_context tx_contexts[MAX_TX_URBS];
259
260 struct usb_anchor rx_submitted;
261
262 struct urb *intr_urb;
263
264 u8 *tx_msg_buffer;
265
266 u8 *intr_in_buffer;
267 unsigned int free_slots; /* remember number of available slots */
268
269 struct ems_cpc_msg active_params; /* active controller parameters */
270 };
271
272 static void ems_usb_read_interrupt_callback(struct urb *urb)
273 {
274 struct ems_usb *dev = urb->context;
275 struct net_device *netdev = dev->netdev;
276 int err;
277
278 if (!netif_device_present(netdev))
279 return;
280
281 switch (urb->status) {
282 case 0:
283 dev->free_slots = dev->intr_in_buffer[1];
284 if(dev->free_slots > CPC_TX_QUEUE_TRIGGER_HIGH){
285 if (netif_queue_stopped(netdev)){
286 netif_wake_queue(netdev);
287 }
288 }
289 break;
290
291 case -ECONNRESET: /* unlink */
292 case -ENOENT:
293 case -ESHUTDOWN:
294 return;
295
296 default:
297 netdev_info(netdev, "Rx interrupt aborted %d\n", urb->status);
298 break;
299 }
300
301 err = usb_submit_urb(urb, GFP_ATOMIC);
302
303 if (err == -ENODEV)
304 netif_device_detach(netdev);
305 else if (err)
306 netdev_err(netdev, "failed resubmitting intr urb: %d\n", err);
307 }
308
309 static void ems_usb_rx_can_msg(struct ems_usb *dev, struct ems_cpc_msg *msg)
310 {
311 struct can_frame *cf;
312 struct sk_buff *skb;
313 int i;
314 struct net_device_stats *stats = &dev->netdev->stats;
315
316 skb = alloc_can_skb(dev->netdev, &cf);
317 if (skb == NULL)
318 return;
319
320 cf->can_id = le32_to_cpu(msg->msg.can_msg.id);
321 cf->can_dlc = get_can_dlc(msg->msg.can_msg.length & 0xF);
322
323 if (msg->type == CPC_MSG_TYPE_EXT_CAN_FRAME ||
324 msg->type == CPC_MSG_TYPE_EXT_RTR_FRAME)
325 cf->can_id |= CAN_EFF_FLAG;
326
327 if (msg->type == CPC_MSG_TYPE_RTR_FRAME ||
328 msg->type == CPC_MSG_TYPE_EXT_RTR_FRAME) {
329 cf->can_id |= CAN_RTR_FLAG;
330 } else {
331 for (i = 0; i < cf->can_dlc; i++)
332 cf->data[i] = msg->msg.can_msg.msg[i];
333 }
334
335 netif_rx(skb);
336
337 stats->rx_packets++;
338 stats->rx_bytes += cf->can_dlc;
339 }
340
341 static void ems_usb_rx_err(struct ems_usb *dev, struct ems_cpc_msg *msg)
342 {
343 struct can_frame *cf;
344 struct sk_buff *skb;
345 struct net_device_stats *stats = &dev->netdev->stats;
346
347 skb = alloc_can_err_skb(dev->netdev, &cf);
348 if (skb == NULL)
349 return;
350
351 if (msg->type == CPC_MSG_TYPE_CAN_STATE) {
352 u8 state = msg->msg.can_state;
353
354 if (state & SJA1000_SR_BS) {
355 dev->can.state = CAN_STATE_BUS_OFF;
356 cf->can_id |= CAN_ERR_BUSOFF;
357
358 can_bus_off(dev->netdev);
359 } else if (state & SJA1000_SR_ES) {
360 dev->can.state = CAN_STATE_ERROR_WARNING;
361 dev->can.can_stats.error_warning++;
362 } else {
363 dev->can.state = CAN_STATE_ERROR_ACTIVE;
364 dev->can.can_stats.error_passive++;
365 }
366 } else if (msg->type == CPC_MSG_TYPE_CAN_FRAME_ERROR) {
367 u8 ecc = msg->msg.error.cc.regs.sja1000.ecc;
368 u8 txerr = msg->msg.error.cc.regs.sja1000.txerr;
369 u8 rxerr = msg->msg.error.cc.regs.sja1000.rxerr;
370
371 /* bus error interrupt */
372 dev->can.can_stats.bus_error++;
373 stats->rx_errors++;
374
375 cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
376
377 switch (ecc & SJA1000_ECC_MASK) {
378 case SJA1000_ECC_BIT:
379 cf->data[2] |= CAN_ERR_PROT_BIT;
380 break;
381 case SJA1000_ECC_FORM:
382 cf->data[2] |= CAN_ERR_PROT_FORM;
383 break;
384 case SJA1000_ECC_STUFF:
385 cf->data[2] |= CAN_ERR_PROT_STUFF;
386 break;
387 default:
388 cf->data[2] |= CAN_ERR_PROT_UNSPEC;
389 cf->data[3] = ecc & SJA1000_ECC_SEG;
390 break;
391 }
392
393 /* Error occurred during transmission? */
394 if ((ecc & SJA1000_ECC_DIR) == 0)
395 cf->data[2] |= CAN_ERR_PROT_TX;
396
397 if (dev->can.state == CAN_STATE_ERROR_WARNING ||
398 dev->can.state == CAN_STATE_ERROR_PASSIVE) {
399 cf->data[1] = (txerr > rxerr) ?
400 CAN_ERR_CRTL_TX_PASSIVE : CAN_ERR_CRTL_RX_PASSIVE;
401 }
402 } else if (msg->type == CPC_MSG_TYPE_OVERRUN) {
403 cf->can_id |= CAN_ERR_CRTL;
404 cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
405
406 stats->rx_over_errors++;
407 stats->rx_errors++;
408 }
409
410 netif_rx(skb);
411
412 stats->rx_packets++;
413 stats->rx_bytes += cf->can_dlc;
414 }
415
416 /*
417 * callback for bulk IN urb
418 */
419 static void ems_usb_read_bulk_callback(struct urb *urb)
420 {
421 struct ems_usb *dev = urb->context;
422 struct net_device *netdev;
423 int retval;
424
425 netdev = dev->netdev;
426
427 if (!netif_device_present(netdev))
428 return;
429
430 switch (urb->status) {
431 case 0: /* success */
432 break;
433
434 case -ENOENT:
435 return;
436
437 default:
438 netdev_info(netdev, "Rx URB aborted (%d)\n", urb->status);
439 goto resubmit_urb;
440 }
441
442 if (urb->actual_length > CPC_HEADER_SIZE) {
443 struct ems_cpc_msg *msg;
444 u8 *ibuf = urb->transfer_buffer;
445 u8 msg_count, start;
446
447 msg_count = ibuf[0] & ~0x80;
448
449 start = CPC_HEADER_SIZE;
450
451 while (msg_count) {
452 msg = (struct ems_cpc_msg *)&ibuf[start];
453
454 switch (msg->type) {
455 case CPC_MSG_TYPE_CAN_STATE:
456 /* Process CAN state changes */
457 ems_usb_rx_err(dev, msg);
458 break;
459
460 case CPC_MSG_TYPE_CAN_FRAME:
461 case CPC_MSG_TYPE_EXT_CAN_FRAME:
462 case CPC_MSG_TYPE_RTR_FRAME:
463 case CPC_MSG_TYPE_EXT_RTR_FRAME:
464 ems_usb_rx_can_msg(dev, msg);
465 break;
466
467 case CPC_MSG_TYPE_CAN_FRAME_ERROR:
468 /* Process errorframe */
469 ems_usb_rx_err(dev, msg);
470 break;
471
472 case CPC_MSG_TYPE_OVERRUN:
473 /* Message lost while receiving */
474 ems_usb_rx_err(dev, msg);
475 break;
476 }
477
478 start += CPC_MSG_HEADER_LEN + msg->length;
479 msg_count--;
480
481 if (start > urb->transfer_buffer_length) {
482 netdev_err(netdev, "format error\n");
483 break;
484 }
485 }
486 }
487
488 resubmit_urb:
489 usb_fill_bulk_urb(urb, dev->udev, usb_rcvbulkpipe(dev->udev, 2),
490 urb->transfer_buffer, RX_BUFFER_SIZE,
491 ems_usb_read_bulk_callback, dev);
492
493 retval = usb_submit_urb(urb, GFP_ATOMIC);
494
495 if (retval == -ENODEV)
496 netif_device_detach(netdev);
497 else if (retval)
498 netdev_err(netdev,
499 "failed resubmitting read bulk urb: %d\n", retval);
500 }
501
502 /*
503 * callback for bulk IN urb
504 */
505 static void ems_usb_write_bulk_callback(struct urb *urb)
506 {
507 struct ems_tx_urb_context *context = urb->context;
508 struct ems_usb *dev;
509 struct net_device *netdev;
510
511 BUG_ON(!context);
512
513 dev = context->dev;
514 netdev = dev->netdev;
515
516 /* free up our allocated buffer */
517 usb_free_coherent(urb->dev, urb->transfer_buffer_length,
518 urb->transfer_buffer, urb->transfer_dma);
519
520 atomic_dec(&dev->active_tx_urbs);
521
522 if (!netif_device_present(netdev))
523 return;
524
525 if (urb->status)
526 netdev_info(netdev, "Tx URB aborted (%d)\n", urb->status);
527
528 netdev->trans_start = jiffies;
529
530 /* transmission complete interrupt */
531 netdev->stats.tx_packets++;
532 netdev->stats.tx_bytes += context->dlc;
533
534 can_get_echo_skb(netdev, context->echo_index);
535
536 /* Release context */
537 context->echo_index = MAX_TX_URBS;
538
539 }
540
541 /*
542 * Send the given CPC command synchronously
543 */
544 static int ems_usb_command_msg(struct ems_usb *dev, struct ems_cpc_msg *msg)
545 {
546 int actual_length;
547
548 /* Copy payload */
549 memcpy(&dev->tx_msg_buffer[CPC_HEADER_SIZE], msg,
550 msg->length + CPC_MSG_HEADER_LEN);
551
552 /* Clear header */
553 memset(&dev->tx_msg_buffer[0], 0, CPC_HEADER_SIZE);
554
555 return usb_bulk_msg(dev->udev, usb_sndbulkpipe(dev->udev, 2),
556 &dev->tx_msg_buffer[0],
557 msg->length + CPC_MSG_HEADER_LEN + CPC_HEADER_SIZE,
558 &actual_length, 1000);
559 }
560
561 /*
562 * Change CAN controllers' mode register
563 */
564 static int ems_usb_write_mode(struct ems_usb *dev, u8 mode)
565 {
566 dev->active_params.msg.can_params.cc_params.sja1000.mode = mode;
567
568 return ems_usb_command_msg(dev, &dev->active_params);
569 }
570
571 /*
572 * Send a CPC_Control command to change behaviour when interface receives a CAN
573 * message, bus error or CAN state changed notifications.
574 */
575 static int ems_usb_control_cmd(struct ems_usb *dev, u8 val)
576 {
577 struct ems_cpc_msg cmd;
578
579 cmd.type = CPC_CMD_TYPE_CONTROL;
580 cmd.length = CPC_MSG_HEADER_LEN + 1;
581
582 cmd.msgid = 0;
583
584 cmd.msg.generic[0] = val;
585
586 return ems_usb_command_msg(dev, &cmd);
587 }
588
589 /*
590 * Start interface
591 */
592 static int ems_usb_start(struct ems_usb *dev)
593 {
594 struct net_device *netdev = dev->netdev;
595 int err, i;
596
597 dev->intr_in_buffer[0] = 0;
598 dev->free_slots = 50; /* initial size */
599
600 for (i = 0; i < MAX_RX_URBS; i++) {
601 struct urb *urb = NULL;
602 u8 *buf = NULL;
603
604 /* create a URB, and a buffer for it */
605 urb = usb_alloc_urb(0, GFP_KERNEL);
606 if (!urb) {
607 netdev_err(netdev, "No memory left for URBs\n");
608 err = -ENOMEM;
609 break;
610 }
611
612 buf = usb_alloc_coherent(dev->udev, RX_BUFFER_SIZE, GFP_KERNEL,
613 &urb->transfer_dma);
614 if (!buf) {
615 netdev_err(netdev, "No memory left for USB buffer\n");
616 usb_free_urb(urb);
617 err = -ENOMEM;
618 break;
619 }
620
621 usb_fill_bulk_urb(urb, dev->udev, usb_rcvbulkpipe(dev->udev, 2),
622 buf, RX_BUFFER_SIZE,
623 ems_usb_read_bulk_callback, dev);
624 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
625 usb_anchor_urb(urb, &dev->rx_submitted);
626
627 err = usb_submit_urb(urb, GFP_KERNEL);
628 if (err) {
629 usb_unanchor_urb(urb);
630 usb_free_coherent(dev->udev, RX_BUFFER_SIZE, buf,
631 urb->transfer_dma);
632 usb_free_urb(urb);
633 break;
634 }
635
636 /* Drop reference, USB core will take care of freeing it */
637 usb_free_urb(urb);
638 }
639
640 /* Did we submit any URBs */
641 if (i == 0) {
642 netdev_warn(netdev, "couldn't setup read URBs\n");
643 return err;
644 }
645
646 /* Warn if we've couldn't transmit all the URBs */
647 if (i < MAX_RX_URBS)
648 netdev_warn(netdev, "rx performance may be slow\n");
649
650 /* Setup and start interrupt URB */
651 usb_fill_int_urb(dev->intr_urb, dev->udev,
652 usb_rcvintpipe(dev->udev, 1),
653 dev->intr_in_buffer,
654 INTR_IN_BUFFER_SIZE,
655 ems_usb_read_interrupt_callback, dev, 1);
656
657 err = usb_submit_urb(dev->intr_urb, GFP_KERNEL);
658 if (err) {
659 netdev_warn(netdev, "intr URB submit failed: %d\n", err);
660
661 return err;
662 }
663
664 /* CPC-USB will transfer received message to host */
665 err = ems_usb_control_cmd(dev, CONTR_CAN_MESSAGE | CONTR_CONT_ON);
666 if (err)
667 goto failed;
668
669 /* CPC-USB will transfer CAN state changes to host */
670 err = ems_usb_control_cmd(dev, CONTR_CAN_STATE | CONTR_CONT_ON);
671 if (err)
672 goto failed;
673
674 /* CPC-USB will transfer bus errors to host */
675 err = ems_usb_control_cmd(dev, CONTR_BUS_ERROR | CONTR_CONT_ON);
676 if (err)
677 goto failed;
678
679 err = ems_usb_write_mode(dev, SJA1000_MOD_NORMAL);
680 if (err)
681 goto failed;
682
683 dev->can.state = CAN_STATE_ERROR_ACTIVE;
684
685 return 0;
686
687 failed:
688 netdev_warn(netdev, "couldn't submit control: %d\n", err);
689
690 return err;
691 }
692
693 static void unlink_all_urbs(struct ems_usb *dev)
694 {
695 int i;
696
697 usb_unlink_urb(dev->intr_urb);
698
699 usb_kill_anchored_urbs(&dev->rx_submitted);
700
701 usb_kill_anchored_urbs(&dev->tx_submitted);
702 atomic_set(&dev->active_tx_urbs, 0);
703
704 for (i = 0; i < MAX_TX_URBS; i++)
705 dev->tx_contexts[i].echo_index = MAX_TX_URBS;
706 }
707
708 static int ems_usb_open(struct net_device *netdev)
709 {
710 struct ems_usb *dev = netdev_priv(netdev);
711 int err;
712
713 err = ems_usb_write_mode(dev, SJA1000_MOD_RM);
714 if (err)
715 return err;
716
717 /* common open */
718 err = open_candev(netdev);
719 if (err)
720 return err;
721
722 /* finally start device */
723 err = ems_usb_start(dev);
724 if (err) {
725 if (err == -ENODEV)
726 netif_device_detach(dev->netdev);
727
728 netdev_warn(netdev, "couldn't start device: %d\n", err);
729
730 close_candev(netdev);
731
732 return err;
733 }
734
735
736 netif_start_queue(netdev);
737
738 return 0;
739 }
740
741 static netdev_tx_t ems_usb_start_xmit(struct sk_buff *skb, struct net_device *netdev)
742 {
743 struct ems_usb *dev = netdev_priv(netdev);
744 struct ems_tx_urb_context *context = NULL;
745 struct net_device_stats *stats = &netdev->stats;
746 struct can_frame *cf = (struct can_frame *)skb->data;
747 struct ems_cpc_msg *msg;
748 struct urb *urb;
749 u8 *buf;
750 int i, err;
751 size_t size = CPC_HEADER_SIZE + CPC_MSG_HEADER_LEN
752 + sizeof(struct cpc_can_msg);
753
754 if (can_dropped_invalid_skb(netdev, skb))
755 return NETDEV_TX_OK;
756
757 /* create a URB, and a buffer for it, and copy the data to the URB */
758 urb = usb_alloc_urb(0, GFP_ATOMIC);
759 if (!urb) {
760 netdev_err(netdev, "No memory left for URBs\n");
761 goto nomem;
762 }
763
764 buf = usb_alloc_coherent(dev->udev, size, GFP_ATOMIC, &urb->transfer_dma);
765 if (!buf) {
766 netdev_err(netdev, "No memory left for USB buffer\n");
767 usb_free_urb(urb);
768 goto nomem;
769 }
770
771 msg = (struct ems_cpc_msg *)&buf[CPC_HEADER_SIZE];
772
773 msg->msg.can_msg.id = cf->can_id & CAN_ERR_MASK;
774 msg->msg.can_msg.length = cf->can_dlc;
775
776 if (cf->can_id & CAN_RTR_FLAG) {
777 msg->type = cf->can_id & CAN_EFF_FLAG ?
778 CPC_CMD_TYPE_EXT_RTR_FRAME : CPC_CMD_TYPE_RTR_FRAME;
779
780 msg->length = CPC_CAN_MSG_MIN_SIZE;
781 } else {
782 msg->type = cf->can_id & CAN_EFF_FLAG ?
783 CPC_CMD_TYPE_EXT_CAN_FRAME : CPC_CMD_TYPE_CAN_FRAME;
784
785 for (i = 0; i < cf->can_dlc; i++)
786 msg->msg.can_msg.msg[i] = cf->data[i];
787
788 msg->length = CPC_CAN_MSG_MIN_SIZE + cf->can_dlc;
789 }
790
791 /* Respect byte order */
792 msg->msg.can_msg.id = cpu_to_le32(msg->msg.can_msg.id);
793
794 for (i = 0; i < MAX_TX_URBS; i++) {
795 if (dev->tx_contexts[i].echo_index == MAX_TX_URBS) {
796 context = &dev->tx_contexts[i];
797 break;
798 }
799 }
800
801 /*
802 * May never happen! When this happens we'd more URBs in flight as
803 * allowed (MAX_TX_URBS).
804 */
805 if (!context) {
806 usb_free_coherent(dev->udev, size, buf, urb->transfer_dma);
807 usb_free_urb(urb);
808
809 netdev_warn(netdev, "couldn't find free context\n");
810
811 return NETDEV_TX_BUSY;
812 }
813
814 context->dev = dev;
815 context->echo_index = i;
816 context->dlc = cf->can_dlc;
817
818 usb_fill_bulk_urb(urb, dev->udev, usb_sndbulkpipe(dev->udev, 2), buf,
819 size, ems_usb_write_bulk_callback, context);
820 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
821 usb_anchor_urb(urb, &dev->tx_submitted);
822
823 can_put_echo_skb(skb, netdev, context->echo_index);
824
825 atomic_inc(&dev->active_tx_urbs);
826
827 err = usb_submit_urb(urb, GFP_ATOMIC);
828 if (unlikely(err)) {
829 can_free_echo_skb(netdev, context->echo_index);
830
831 usb_unanchor_urb(urb);
832 usb_free_coherent(dev->udev, size, buf, urb->transfer_dma);
833 dev_kfree_skb(skb);
834
835 atomic_dec(&dev->active_tx_urbs);
836
837 if (err == -ENODEV) {
838 netif_device_detach(netdev);
839 } else {
840 netdev_warn(netdev, "failed tx_urb %d\n", err);
841
842 stats->tx_dropped++;
843 }
844 } else {
845 netdev->trans_start = jiffies;
846
847 /* Slow down tx path */
848 if (atomic_read(&dev->active_tx_urbs) >= MAX_TX_URBS ||
849 dev->free_slots < CPC_TX_QUEUE_TRIGGER_LOW) {
850 netif_stop_queue(netdev);
851 }
852 }
853
854 /*
855 * Release our reference to this URB, the USB core will eventually free
856 * it entirely.
857 */
858 usb_free_urb(urb);
859
860 return NETDEV_TX_OK;
861
862 nomem:
863 dev_kfree_skb(skb);
864 stats->tx_dropped++;
865
866 return NETDEV_TX_OK;
867 }
868
869 static int ems_usb_close(struct net_device *netdev)
870 {
871 struct ems_usb *dev = netdev_priv(netdev);
872
873 /* Stop polling */
874 unlink_all_urbs(dev);
875
876 netif_stop_queue(netdev);
877
878 /* Set CAN controller to reset mode */
879 if (ems_usb_write_mode(dev, SJA1000_MOD_RM))
880 netdev_warn(netdev, "couldn't stop device");
881
882 close_candev(netdev);
883
884 return 0;
885 }
886
887 static const struct net_device_ops ems_usb_netdev_ops = {
888 .ndo_open = ems_usb_open,
889 .ndo_stop = ems_usb_close,
890 .ndo_start_xmit = ems_usb_start_xmit,
891 .ndo_change_mtu = can_change_mtu,
892 };
893
894 static const struct can_bittiming_const ems_usb_bittiming_const = {
895 .name = "ems_usb",
896 .tseg1_min = 1,
897 .tseg1_max = 16,
898 .tseg2_min = 1,
899 .tseg2_max = 8,
900 .sjw_max = 4,
901 .brp_min = 1,
902 .brp_max = 64,
903 .brp_inc = 1,
904 };
905
906 static int ems_usb_set_mode(struct net_device *netdev, enum can_mode mode)
907 {
908 struct ems_usb *dev = netdev_priv(netdev);
909
910 switch (mode) {
911 case CAN_MODE_START:
912 if (ems_usb_write_mode(dev, SJA1000_MOD_NORMAL))
913 netdev_warn(netdev, "couldn't start device");
914
915 if (netif_queue_stopped(netdev))
916 netif_wake_queue(netdev);
917 break;
918
919 default:
920 return -EOPNOTSUPP;
921 }
922
923 return 0;
924 }
925
926 static int ems_usb_set_bittiming(struct net_device *netdev)
927 {
928 struct ems_usb *dev = netdev_priv(netdev);
929 struct can_bittiming *bt = &dev->can.bittiming;
930 u8 btr0, btr1;
931
932 btr0 = ((bt->brp - 1) & 0x3f) | (((bt->sjw - 1) & 0x3) << 6);
933 btr1 = ((bt->prop_seg + bt->phase_seg1 - 1) & 0xf) |
934 (((bt->phase_seg2 - 1) & 0x7) << 4);
935 if (dev->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
936 btr1 |= 0x80;
937
938 netdev_info(netdev, "setting BTR0=0x%02x BTR1=0x%02x\n", btr0, btr1);
939
940 dev->active_params.msg.can_params.cc_params.sja1000.btr0 = btr0;
941 dev->active_params.msg.can_params.cc_params.sja1000.btr1 = btr1;
942
943 return ems_usb_command_msg(dev, &dev->active_params);
944 }
945
946 static void init_params_sja1000(struct ems_cpc_msg *msg)
947 {
948 struct cpc_sja1000_params *sja1000 =
949 &msg->msg.can_params.cc_params.sja1000;
950
951 msg->type = CPC_CMD_TYPE_CAN_PARAMS;
952 msg->length = sizeof(struct cpc_can_params);
953 msg->msgid = 0;
954
955 msg->msg.can_params.cc_type = CPC_CC_TYPE_SJA1000;
956
957 /* Acceptance filter open */
958 sja1000->acc_code0 = 0x00;
959 sja1000->acc_code1 = 0x00;
960 sja1000->acc_code2 = 0x00;
961 sja1000->acc_code3 = 0x00;
962
963 /* Acceptance filter open */
964 sja1000->acc_mask0 = 0xFF;
965 sja1000->acc_mask1 = 0xFF;
966 sja1000->acc_mask2 = 0xFF;
967 sja1000->acc_mask3 = 0xFF;
968
969 sja1000->btr0 = 0;
970 sja1000->btr1 = 0;
971
972 sja1000->outp_contr = SJA1000_DEFAULT_OUTPUT_CONTROL;
973 sja1000->mode = SJA1000_MOD_RM;
974 }
975
976 /*
977 * probe function for new CPC-USB devices
978 */
979 static int ems_usb_probe(struct usb_interface *intf,
980 const struct usb_device_id *id)
981 {
982 struct net_device *netdev;
983 struct ems_usb *dev;
984 int i, err = -ENOMEM;
985
986 netdev = alloc_candev(sizeof(struct ems_usb), MAX_TX_URBS);
987 if (!netdev) {
988 dev_err(&intf->dev, "ems_usb: Couldn't alloc candev\n");
989 return -ENOMEM;
990 }
991
992 dev = netdev_priv(netdev);
993
994 dev->udev = interface_to_usbdev(intf);
995 dev->netdev = netdev;
996
997 dev->can.state = CAN_STATE_STOPPED;
998 dev->can.clock.freq = EMS_USB_ARM7_CLOCK;
999 dev->can.bittiming_const = &ems_usb_bittiming_const;
1000 dev->can.do_set_bittiming = ems_usb_set_bittiming;
1001 dev->can.do_set_mode = ems_usb_set_mode;
1002 dev->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES;
1003
1004 netdev->netdev_ops = &ems_usb_netdev_ops;
1005
1006 netdev->flags |= IFF_ECHO; /* we support local echo */
1007
1008 init_usb_anchor(&dev->rx_submitted);
1009
1010 init_usb_anchor(&dev->tx_submitted);
1011 atomic_set(&dev->active_tx_urbs, 0);
1012
1013 for (i = 0; i < MAX_TX_URBS; i++)
1014 dev->tx_contexts[i].echo_index = MAX_TX_URBS;
1015
1016 dev->intr_urb = usb_alloc_urb(0, GFP_KERNEL);
1017 if (!dev->intr_urb) {
1018 dev_err(&intf->dev, "Couldn't alloc intr URB\n");
1019 goto cleanup_candev;
1020 }
1021
1022 dev->intr_in_buffer = kzalloc(INTR_IN_BUFFER_SIZE, GFP_KERNEL);
1023 if (!dev->intr_in_buffer)
1024 goto cleanup_intr_urb;
1025
1026 dev->tx_msg_buffer = kzalloc(CPC_HEADER_SIZE +
1027 sizeof(struct ems_cpc_msg), GFP_KERNEL);
1028 if (!dev->tx_msg_buffer)
1029 goto cleanup_intr_in_buffer;
1030
1031 usb_set_intfdata(intf, dev);
1032
1033 SET_NETDEV_DEV(netdev, &intf->dev);
1034
1035 init_params_sja1000(&dev->active_params);
1036
1037 err = ems_usb_command_msg(dev, &dev->active_params);
1038 if (err) {
1039 netdev_err(netdev, "couldn't initialize controller: %d\n", err);
1040 goto cleanup_tx_msg_buffer;
1041 }
1042
1043 err = register_candev(netdev);
1044 if (err) {
1045 netdev_err(netdev, "couldn't register CAN device: %d\n", err);
1046 goto cleanup_tx_msg_buffer;
1047 }
1048
1049 return 0;
1050
1051 cleanup_tx_msg_buffer:
1052 kfree(dev->tx_msg_buffer);
1053
1054 cleanup_intr_in_buffer:
1055 kfree(dev->intr_in_buffer);
1056
1057 cleanup_intr_urb:
1058 usb_free_urb(dev->intr_urb);
1059
1060 cleanup_candev:
1061 free_candev(netdev);
1062
1063 return err;
1064 }
1065
1066 /*
1067 * called by the usb core when the device is removed from the system
1068 */
1069 static void ems_usb_disconnect(struct usb_interface *intf)
1070 {
1071 struct ems_usb *dev = usb_get_intfdata(intf);
1072
1073 usb_set_intfdata(intf, NULL);
1074
1075 if (dev) {
1076 unregister_netdev(dev->netdev);
1077 free_candev(dev->netdev);
1078
1079 unlink_all_urbs(dev);
1080
1081 usb_free_urb(dev->intr_urb);
1082
1083 kfree(dev->intr_in_buffer);
1084 }
1085 }
1086
1087 /* usb specific object needed to register this driver with the usb subsystem */
1088 static struct usb_driver ems_usb_driver = {
1089 .name = "ems_usb",
1090 .probe = ems_usb_probe,
1091 .disconnect = ems_usb_disconnect,
1092 .id_table = ems_usb_table,
1093 };
1094
1095 module_usb_driver(ems_usb_driver);
Linux with added FPC-III support