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can: Unify MTU settings for CAN interfaces
[deliverable/linux.git] / drivers / net / can / usb / ems_usb.c
CommitLineData
702171ad
SH		 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 */
702171ad
SH		 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
29MODULE_AUTHOR("Sebastian Haas <haas@ems-wuensche.com>");
30MODULE_DESCRIPTION("CAN driver for EMS Dr. Thomas Wuensche CAN/USB interfaces");
31MODULE_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/*
121 * CAN-Message representation in a CPC_MSG. Message object type is
122 * CPC_MSG_TYPE_CAN_FRAME or CPC_MSG_TYPE_RTR_FRAME or
123 * CPC_MSG_TYPE_EXT_CAN_FRAME or CPC_MSG_TYPE_EXT_RTR_FRAME.
124 */
125struct cpc_can_msg {
126 u32 id;
127 u8 length;
128 u8 msg[8];
129};
130
131/* Representation of the CAN parameters for the SJA1000 controller */
132struct cpc_sja1000_params {
133 u8 mode;
134 u8 acc_code0;
135 u8 acc_code1;
136 u8 acc_code2;
137 u8 acc_code3;
138 u8 acc_mask0;
139 u8 acc_mask1;
140 u8 acc_mask2;
141 u8 acc_mask3;
142 u8 btr0;
143 u8 btr1;
144 u8 outp_contr;
145};
146
147/* CAN params message representation */
148struct cpc_can_params {
149 u8 cc_type;
150
151 /* Will support M16C CAN controller in the future */
152 union {
153 struct cpc_sja1000_params sja1000;
154 } cc_params;
155};
156
157/* Structure for confirmed message handling */
158struct cpc_confirm {
159 u8 error; /* error code */
160};
161
162/* Structure for overrun conditions */
163struct cpc_overrun {
164 u8 event;
165 u8 count;
166};
167
168/* SJA1000 CAN errors (compatible to NXP LPC2119) */
169struct cpc_sja1000_can_error {
170 u8 ecc;
171 u8 rxerr;
172 u8 txerr;
173};
174
175/* structure for CAN error conditions */
176struct cpc_can_error {
177 u8 ecode;
178
179 struct {
180 u8 cc_type;
181
182 /* Other controllers may also provide error code capture regs */
183 union {
184 struct cpc_sja1000_can_error sja1000;
185 } regs;
186 } cc;
187};
188
189/*
190 * Structure containing RX/TX error counter. This structure is used to request
191 * the values of the CAN controllers TX and RX error counter.
192 */
193struct cpc_can_err_counter {
194 u8 rx;
195 u8 tx;
196};
197
198/* Main message type used between library and application */
ba2d3587 199struct __packed ems_cpc_msg {
702171ad
SH		 200 u8 type; /* type of message */
201 u8 length; /* length of data within union 'msg' */
202 u8 msgid; /* confirmation handle */
203 u32 ts_sec; /* timestamp in seconds */
204 u32 ts_nsec; /* timestamp in nano seconds */
205
206 union {
207 u8 generic[64];
208 struct cpc_can_msg can_msg;
209 struct cpc_can_params can_params;
210 struct cpc_confirm confirmation;
211 struct cpc_overrun overrun;
212 struct cpc_can_error error;
213 struct cpc_can_err_counter err_counter;
214 u8 can_state;
215 } msg;
216};
217
218/*
219 * Table of devices that work with this driver
220 * NOTE: This driver supports only CPC-USB/ARM7 (LPC2119) yet.
221 */
222static struct usb_device_id ems_usb_table[] = {
223 {USB_DEVICE(USB_CPCUSB_VENDOR_ID, USB_CPCUSB_ARM7_PRODUCT_ID)},
224 {} /* Terminating entry */
225};
226
227MODULE_DEVICE_TABLE(usb, ems_usb_table);
228
229#define RX_BUFFER_SIZE 64
230#define CPC_HEADER_SIZE 4
231#define INTR_IN_BUFFER_SIZE 4
232
233#define MAX_RX_URBS 10
a6e4bc53 234#define MAX_TX_URBS 10
702171ad
SH		 235
236struct ems_usb;
237
238struct ems_tx_urb_context {
239 struct ems_usb *dev;
240
241 u32 echo_index;
242 u8 dlc;
243};
244
245struct ems_usb {
246 struct can_priv can; /* must be the first member */
702171ad
SH		 247
248 struct sk_buff *echo_skb[MAX_TX_URBS];
249
250 struct usb_device *udev;
251 struct net_device *netdev;
252
253 atomic_t active_tx_urbs;
254 struct usb_anchor tx_submitted;
255 struct ems_tx_urb_context tx_contexts[MAX_TX_URBS];
256
257 struct usb_anchor rx_submitted;
258
259 struct urb *intr_urb;
260
261 u8 *tx_msg_buffer;
262
263 u8 *intr_in_buffer;
264 unsigned int free_slots; /* remember number of available slots */
265
266 struct ems_cpc_msg active_params; /* active controller parameters */
267};
268
269static void ems_usb_read_interrupt_callback(struct urb *urb)
270{
271 struct ems_usb *dev = urb->context;
272 struct net_device *netdev = dev->netdev;
273 int err;
274
275 if (!netif_device_present(netdev))
276 return;
277
278 switch (urb->status) {
279 case 0:
280 dev->free_slots = dev->intr_in_buffer[1];
281 break;
282
283 case -ECONNRESET: /* unlink */
284 case -ENOENT:
285 case -ESHUTDOWN:
286 return;
287
288 default:
aabdfd6a 289 netdev_info(netdev, "Rx interrupt aborted %d\n", urb->status);
702171ad
SH		 290 break;
291 }
292
293 err = usb_submit_urb(urb, GFP_ATOMIC);
294
295 if (err == -ENODEV)
296 netif_device_detach(netdev);
297 else if (err)
aabdfd6a 298 netdev_err(netdev, "failed resubmitting intr urb: %d\n", err);
702171ad
SH		 299}
300
301static void ems_usb_rx_can_msg(struct ems_usb *dev, struct ems_cpc_msg *msg)
302{
303 struct can_frame *cf;
304 struct sk_buff *skb;
305 int i;
306 struct net_device_stats *stats = &dev->netdev->stats;
307
7b6856a0 308 skb = alloc_can_skb(dev->netdev, &cf);
702171ad
SH		 309 if (skb == NULL)
310 return;
311
2b2072e9 312 cf->can_id = le32_to_cpu(msg->msg.can_msg.id);
c7cd606f 313 cf->can_dlc = get_can_dlc(msg->msg.can_msg.length & 0xF);
702171ad 314
8e95a202
JP		 315 if (msg->type == CPC_MSG_TYPE_EXT_CAN_FRAME ||
316 msg->type == CPC_MSG_TYPE_EXT_RTR_FRAME)
702171ad
SH		 317 cf->can_id |= CAN_EFF_FLAG;
318
8e95a202
JP		 319 if (msg->type == CPC_MSG_TYPE_RTR_FRAME ||
320 msg->type == CPC_MSG_TYPE_EXT_RTR_FRAME) {
702171ad
SH		 321 cf->can_id |= CAN_RTR_FLAG;
322 } else {
323 for (i = 0; i < cf->can_dlc; i++)
324 cf->data[i] = msg->msg.can_msg.msg[i];
325 }
326
327 netif_rx(skb);
328
329 stats->rx_packets++;
330 stats->rx_bytes += cf->can_dlc;
331}
332
333static void ems_usb_rx_err(struct ems_usb *dev, struct ems_cpc_msg *msg)
334{
335 struct can_frame *cf;
336 struct sk_buff *skb;
337 struct net_device_stats *stats = &dev->netdev->stats;
338
7b6856a0 339 skb = alloc_can_err_skb(dev->netdev, &cf);
702171ad
SH		 340 if (skb == NULL)
341 return;
342
702171ad
SH		 343 if (msg->type == CPC_MSG_TYPE_CAN_STATE) {
344 u8 state = msg->msg.can_state;
345
346 if (state & SJA1000_SR_BS) {
347 dev->can.state = CAN_STATE_BUS_OFF;
348 cf->can_id |= CAN_ERR_BUSOFF;
349
350 can_bus_off(dev->netdev);
351 } else if (state & SJA1000_SR_ES) {
352 dev->can.state = CAN_STATE_ERROR_WARNING;
353 dev->can.can_stats.error_warning++;
354 } else {
355 dev->can.state = CAN_STATE_ERROR_ACTIVE;
356 dev->can.can_stats.error_passive++;
357 }
358 } else if (msg->type == CPC_MSG_TYPE_CAN_FRAME_ERROR) {
359 u8 ecc = msg->msg.error.cc.regs.sja1000.ecc;
360 u8 txerr = msg->msg.error.cc.regs.sja1000.txerr;
361 u8 rxerr = msg->msg.error.cc.regs.sja1000.rxerr;
362
363 /* bus error interrupt */
364 dev->can.can_stats.bus_error++;
365 stats->rx_errors++;
366
367 cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
368
369 switch (ecc & SJA1000_ECC_MASK) {
370 case SJA1000_ECC_BIT:
371 cf->data[2] |= CAN_ERR_PROT_BIT;
372 break;
373 case SJA1000_ECC_FORM:
374 cf->data[2] |= CAN_ERR_PROT_FORM;
375 break;
376 case SJA1000_ECC_STUFF:
377 cf->data[2] |= CAN_ERR_PROT_STUFF;
378 break;
379 default:
380 cf->data[2] |= CAN_ERR_PROT_UNSPEC;
381 cf->data[3] = ecc & SJA1000_ECC_SEG;
382 break;
383 }
384
25985edc 385 /* Error occurred during transmission? */
702171ad
SH		 386 if ((ecc & SJA1000_ECC_DIR) == 0)
387 cf->data[2] |= CAN_ERR_PROT_TX;
388
389 if (dev->can.state == CAN_STATE_ERROR_WARNING ||
390 dev->can.state == CAN_STATE_ERROR_PASSIVE) {
391 cf->data[1] = (txerr > rxerr) ?
392 CAN_ERR_CRTL_TX_PASSIVE : CAN_ERR_CRTL_RX_PASSIVE;
393 }
394 } else if (msg->type == CPC_MSG_TYPE_OVERRUN) {
395 cf->can_id |= CAN_ERR_CRTL;
396 cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
397
398 stats->rx_over_errors++;
399 stats->rx_errors++;
400 }
401
402 netif_rx(skb);
403
404 stats->rx_packets++;
405 stats->rx_bytes += cf->can_dlc;
406}
407
408/*
409 * callback for bulk IN urb
410 */
411static void ems_usb_read_bulk_callback(struct urb *urb)
412{
413 struct ems_usb *dev = urb->context;
414 struct net_device *netdev;
415 int retval;
416
417 netdev = dev->netdev;
418
419 if (!netif_device_present(netdev))
420 return;
421
422 switch (urb->status) {
423 case 0: /* success */
424 break;
425
426 case -ENOENT:
427 return;
428
429 default:
aabdfd6a 430 netdev_info(netdev, "Rx URB aborted (%d)\n", urb->status);
702171ad
SH		 431 goto resubmit_urb;
432 }
433
434 if (urb->actual_length > CPC_HEADER_SIZE) {
435 struct ems_cpc_msg *msg;
436 u8 *ibuf = urb->transfer_buffer;
437 u8 msg_count, again, start;
438
439 msg_count = ibuf[0] & ~0x80;
440 again = ibuf[0] & 0x80;
441
442 start = CPC_HEADER_SIZE;
443
444 while (msg_count) {
445 msg = (struct ems_cpc_msg *)&ibuf[start];
446
447 switch (msg->type) {
448 case CPC_MSG_TYPE_CAN_STATE:
449 /* Process CAN state changes */
450 ems_usb_rx_err(dev, msg);
451 break;
452
453 case CPC_MSG_TYPE_CAN_FRAME:
454 case CPC_MSG_TYPE_EXT_CAN_FRAME:
455 case CPC_MSG_TYPE_RTR_FRAME:
456 case CPC_MSG_TYPE_EXT_RTR_FRAME:
457 ems_usb_rx_can_msg(dev, msg);
458 break;
459
460 case CPC_MSG_TYPE_CAN_FRAME_ERROR:
461 /* Process errorframe */
462 ems_usb_rx_err(dev, msg);
463 break;
464
465 case CPC_MSG_TYPE_OVERRUN:
466 /* Message lost while receiving */
467 ems_usb_rx_err(dev, msg);
468 break;
469 }
470
471 start += CPC_MSG_HEADER_LEN + msg->length;
472 msg_count--;
473
474 if (start > urb->transfer_buffer_length) {
aabdfd6a 475 netdev_err(netdev, "format error\n");
702171ad
SH		 476 break;
477 }
478 }
479 }
480
481resubmit_urb:
482 usb_fill_bulk_urb(urb, dev->udev, usb_rcvbulkpipe(dev->udev, 2),
483 urb->transfer_buffer, RX_BUFFER_SIZE,
484 ems_usb_read_bulk_callback, dev);
485
486 retval = usb_submit_urb(urb, GFP_ATOMIC);
487
488 if (retval == -ENODEV)
489 netif_device_detach(netdev);
490 else if (retval)
aabdfd6a
WG		 491 netdev_err(netdev,
492 "failed resubmitting read bulk urb: %d\n", retval);
702171ad
SH		 493}
494
495/*
496 * callback for bulk IN urb
497 */
498static void ems_usb_write_bulk_callback(struct urb *urb)
499{
500 struct ems_tx_urb_context *context = urb->context;
501 struct ems_usb *dev;
502 struct net_device *netdev;
503
504 BUG_ON(!context);
505
506 dev = context->dev;
507 netdev = dev->netdev;
508
509 /* free up our allocated buffer */
997ea58e
DM		 510 usb_free_coherent(urb->dev, urb->transfer_buffer_length,
511 urb->transfer_buffer, urb->transfer_dma);
702171ad
SH		 512
513 atomic_dec(&dev->active_tx_urbs);
514
515 if (!netif_device_present(netdev))
516 return;
517
518 if (urb->status)
aabdfd6a 519 netdev_info(netdev, "Tx URB aborted (%d)\n", urb->status);
702171ad
SH		 520
521 netdev->trans_start = jiffies;
522
523 /* transmission complete interrupt */
524 netdev->stats.tx_packets++;
525 netdev->stats.tx_bytes += context->dlc;
526
527 can_get_echo_skb(netdev, context->echo_index);
528
529 /* Release context */
530 context->echo_index = MAX_TX_URBS;
531
532 if (netif_queue_stopped(netdev))
533 netif_wake_queue(netdev);
534}
535
536/*
537 * Send the given CPC command synchronously
538 */
539static int ems_usb_command_msg(struct ems_usb *dev, struct ems_cpc_msg *msg)
540{
541 int actual_length;
542
543 /* Copy payload */
544 memcpy(&dev->tx_msg_buffer[CPC_HEADER_SIZE], msg,
545 msg->length + CPC_MSG_HEADER_LEN);
546
547 /* Clear header */
548 memset(&dev->tx_msg_buffer[0], 0, CPC_HEADER_SIZE);
549
550 return usb_bulk_msg(dev->udev, usb_sndbulkpipe(dev->udev, 2),
551 &dev->tx_msg_buffer[0],
552 msg->length + CPC_MSG_HEADER_LEN + CPC_HEADER_SIZE,
553 &actual_length, 1000);
554}
555
556/*
557 * Change CAN controllers' mode register
558 */
559static int ems_usb_write_mode(struct ems_usb *dev, u8 mode)
560{
561 dev->active_params.msg.can_params.cc_params.sja1000.mode = mode;
562
563 return ems_usb_command_msg(dev, &dev->active_params);
564}
565
566/*
567 * Send a CPC_Control command to change behaviour when interface receives a CAN
568 * message, bus error or CAN state changed notifications.
569 */
570static int ems_usb_control_cmd(struct ems_usb *dev, u8 val)
571{
572 struct ems_cpc_msg cmd;
573
574 cmd.type = CPC_CMD_TYPE_CONTROL;
575 cmd.length = CPC_MSG_HEADER_LEN + 1;
576
577 cmd.msgid = 0;
578
579 cmd.msg.generic[0] = val;
580
581 return ems_usb_command_msg(dev, &cmd);
582}
583
584/*
585 * Start interface
586 */
587static int ems_usb_start(struct ems_usb *dev)
588{
589 struct net_device *netdev = dev->netdev;
590 int err, i;
591
592 dev->intr_in_buffer[0] = 0;
593 dev->free_slots = 15; /* initial size */
594
595 for (i = 0; i < MAX_RX_URBS; i++) {
596 struct urb *urb = NULL;
597 u8 *buf = NULL;
598
599 /* create a URB, and a buffer for it */
600 urb = usb_alloc_urb(0, GFP_KERNEL);
601 if (!urb) {
aabdfd6a 602 netdev_err(netdev, "No memory left for URBs\n");
2ee6850c
SH		 603 err = -ENOMEM;
604 break;
702171ad
SH		 605 }
606
997ea58e
DM		 607 buf = usb_alloc_coherent(dev->udev, RX_BUFFER_SIZE, GFP_KERNEL,
608 &urb->transfer_dma);
702171ad 609 if (!buf) {
aabdfd6a 610 netdev_err(netdev, "No memory left for USB buffer\n");
702171ad 611 usb_free_urb(urb);
2ee6850c
SH		 612 err = -ENOMEM;
613 break;
702171ad
SH		 614 }
615
616 usb_fill_bulk_urb(urb, dev->udev, usb_rcvbulkpipe(dev->udev, 2),
617 buf, RX_BUFFER_SIZE,
618 ems_usb_read_bulk_callback, dev);
619 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
620 usb_anchor_urb(urb, &dev->rx_submitted);
621
622 err = usb_submit_urb(urb, GFP_KERNEL);
623 if (err) {
702171ad 624 usb_unanchor_urb(urb);
997ea58e
DM		 625 usb_free_coherent(dev->udev, RX_BUFFER_SIZE, buf,
626 urb->transfer_dma);
a1c31f1d 627 usb_free_urb(urb);
702171ad
SH		 628 break;
629 }
630
631 /* Drop reference, USB core will take care of freeing it */
632 usb_free_urb(urb);
633 }
634
635 /* Did we submit any URBs */
636 if (i == 0) {
aabdfd6a 637 netdev_warn(netdev, "couldn't setup read URBs\n");
702171ad
SH		 638 return err;
639 }
640
641 /* Warn if we've couldn't transmit all the URBs */
642 if (i < MAX_RX_URBS)
aabdfd6a 643 netdev_warn(netdev, "rx performance may be slow\n");
702171ad
SH		 644
645 /* Setup and start interrupt URB */
646 usb_fill_int_urb(dev->intr_urb, dev->udev,
647 usb_rcvintpipe(dev->udev, 1),
648 dev->intr_in_buffer,
649 INTR_IN_BUFFER_SIZE,
650 ems_usb_read_interrupt_callback, dev, 1);
651
652 err = usb_submit_urb(dev->intr_urb, GFP_KERNEL);
653 if (err) {
aabdfd6a 654 netdev_warn(netdev, "intr URB submit failed: %d\n", err);
702171ad
SH		 655
656 return err;
657 }
658
659 /* CPC-USB will transfer received message to host */
660 err = ems_usb_control_cmd(dev, CONTR_CAN_MESSAGE | CONTR_CONT_ON);
661 if (err)
662 goto failed;
663
664 /* CPC-USB will transfer CAN state changes to host */
665 err = ems_usb_control_cmd(dev, CONTR_CAN_STATE | CONTR_CONT_ON);
666 if (err)
667 goto failed;
668
669 /* CPC-USB will transfer bus errors to host */
670 err = ems_usb_control_cmd(dev, CONTR_BUS_ERROR | CONTR_CONT_ON);
671 if (err)
672 goto failed;
673
674 err = ems_usb_write_mode(dev, SJA1000_MOD_NORMAL);
675 if (err)
676 goto failed;
677
678 dev->can.state = CAN_STATE_ERROR_ACTIVE;
679
680 return 0;
681
682failed:
aabdfd6a 683 netdev_warn(netdev, "couldn't submit control: %d\n", err);
702171ad
SH		 684
685 return err;
686}
687
688static void unlink_all_urbs(struct ems_usb *dev)
689{
690 int i;
691
692 usb_unlink_urb(dev->intr_urb);
693
694 usb_kill_anchored_urbs(&dev->rx_submitted);
695
696 usb_kill_anchored_urbs(&dev->tx_submitted);
697 atomic_set(&dev->active_tx_urbs, 0);
698
699 for (i = 0; i < MAX_TX_URBS; i++)
700 dev->tx_contexts[i].echo_index = MAX_TX_URBS;
701}
702
703static int ems_usb_open(struct net_device *netdev)
704{
705 struct ems_usb *dev = netdev_priv(netdev);
706 int err;
707
708 err = ems_usb_write_mode(dev, SJA1000_MOD_RM);
709 if (err)
710 return err;
711
712 /* common open */
713 err = open_candev(netdev);
714 if (err)
715 return err;
716
717 /* finally start device */
718 err = ems_usb_start(dev);
719 if (err) {
720 if (err == -ENODEV)
721 netif_device_detach(dev->netdev);
722
aabdfd6a 723 netdev_warn(netdev, "couldn't start device: %d\n", err);
702171ad
SH		 724
725 close_candev(netdev);
726
727 return err;
728 }
729
702171ad
SH		 730
731 netif_start_queue(netdev);
732
733 return 0;
734}
735
736static netdev_tx_t ems_usb_start_xmit(struct sk_buff *skb, struct net_device *netdev)
737{
738 struct ems_usb *dev = netdev_priv(netdev);
739 struct ems_tx_urb_context *context = NULL;
740 struct net_device_stats *stats = &netdev->stats;
741 struct can_frame *cf = (struct can_frame *)skb->data;
742 struct ems_cpc_msg *msg;
743 struct urb *urb;
744 u8 *buf;
745 int i, err;
746 size_t size = CPC_HEADER_SIZE + CPC_MSG_HEADER_LEN
747 + sizeof(struct cpc_can_msg);
748
3ccd4c61
OH		 749 if (can_dropped_invalid_skb(netdev, skb))
750 return NETDEV_TX_OK;
751
702171ad
SH		 752 /* create a URB, and a buffer for it, and copy the data to the URB */
753 urb = usb_alloc_urb(0, GFP_ATOMIC);
754 if (!urb) {
aabdfd6a 755 netdev_err(netdev, "No memory left for URBs\n");
702171ad
SH		 756 goto nomem;
757 }
758
997ea58e 759 buf = usb_alloc_coherent(dev->udev, size, GFP_ATOMIC, &urb->transfer_dma);
702171ad 760 if (!buf) {
aabdfd6a 761 netdev_err(netdev, "No memory left for USB buffer\n");
702171ad
SH		 762 usb_free_urb(urb);
763 goto nomem;
764 }
765
766 msg = (struct ems_cpc_msg *)&buf[CPC_HEADER_SIZE];
767
768 msg->msg.can_msg.id = cf->can_id & CAN_ERR_MASK;
769 msg->msg.can_msg.length = cf->can_dlc;
770
771 if (cf->can_id & CAN_RTR_FLAG) {
772 msg->type = cf->can_id & CAN_EFF_FLAG ?
773 CPC_CMD_TYPE_EXT_RTR_FRAME : CPC_CMD_TYPE_RTR_FRAME;
774
775 msg->length = CPC_CAN_MSG_MIN_SIZE;
776 } else {
777 msg->type = cf->can_id & CAN_EFF_FLAG ?
778 CPC_CMD_TYPE_EXT_CAN_FRAME : CPC_CMD_TYPE_CAN_FRAME;
779
780 for (i = 0; i < cf->can_dlc; i++)
781 msg->msg.can_msg.msg[i] = cf->data[i];
782
783 msg->length = CPC_CAN_MSG_MIN_SIZE + cf->can_dlc;
784 }
785
2b2072e9
SH		 786 /* Respect byte order */
787 msg->msg.can_msg.id = cpu_to_le32(msg->msg.can_msg.id);
788
702171ad
SH		 789 for (i = 0; i < MAX_TX_URBS; i++) {
790 if (dev->tx_contexts[i].echo_index == MAX_TX_URBS) {
791 context = &dev->tx_contexts[i];
792 break;
793 }
794 }
795
796 /*
797 * May never happen! When this happens we'd more URBs in flight as
798 * allowed (MAX_TX_URBS).
799 */
800 if (!context) {
997ea58e 801 usb_free_coherent(dev->udev, size, buf, urb->transfer_dma);
a1c31f1d 802 usb_free_urb(urb);
702171ad 803
aabdfd6a 804 netdev_warn(netdev, "couldn't find free context\n");
702171ad
SH		 805
806 return NETDEV_TX_BUSY;
807 }
808
809 context->dev = dev;
810 context->echo_index = i;
811 context->dlc = cf->can_dlc;
812
813 usb_fill_bulk_urb(urb, dev->udev, usb_sndbulkpipe(dev->udev, 2), buf,
814 size, ems_usb_write_bulk_callback, context);
815 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
816 usb_anchor_urb(urb, &dev->tx_submitted);
817
818 can_put_echo_skb(skb, netdev, context->echo_index);
819
820 atomic_inc(&dev->active_tx_urbs);
821
822 err = usb_submit_urb(urb, GFP_ATOMIC);
823 if (unlikely(err)) {
824 can_free_echo_skb(netdev, context->echo_index);
825
826 usb_unanchor_urb(urb);
997ea58e 827 usb_free_coherent(dev->udev, size, buf, urb->transfer_dma);
702171ad
SH		 828 dev_kfree_skb(skb);
829
830 atomic_dec(&dev->active_tx_urbs);
831
832 if (err == -ENODEV) {
833 netif_device_detach(netdev);
834 } else {
aabdfd6a 835 netdev_warn(netdev, "failed tx_urb %d\n", err);
702171ad
SH		 836
837 stats->tx_dropped++;
838 }
839 } else {
840 netdev->trans_start = jiffies;
841
842 /* Slow down tx path */
843 if (atomic_read(&dev->active_tx_urbs) >= MAX_TX_URBS ||
844 dev->free_slots < 5) {
845 netif_stop_queue(netdev);
846 }
847 }
848
849 /*
850 * Release our reference to this URB, the USB core will eventually free
851 * it entirely.
852 */
853 usb_free_urb(urb);
854
855 return NETDEV_TX_OK;
856
857nomem:
ea3fb371 858 dev_kfree_skb(skb);
702171ad
SH		 859 stats->tx_dropped++;
860
861 return NETDEV_TX_OK;
862}
863
864static int ems_usb_close(struct net_device *netdev)
865{
866 struct ems_usb *dev = netdev_priv(netdev);
867
868 /* Stop polling */
869 unlink_all_urbs(dev);
870
871 netif_stop_queue(netdev);
872
873 /* Set CAN controller to reset mode */
874 if (ems_usb_write_mode(dev, SJA1000_MOD_RM))
aabdfd6a 875 netdev_warn(netdev, "couldn't stop device");
702171ad
SH		 876
877 close_candev(netdev);
878
702171ad
SH		 879 return 0;
880}
881
882static const struct net_device_ops ems_usb_netdev_ops = {
883 .ndo_open = ems_usb_open,
884 .ndo_stop = ems_usb_close,
885 .ndo_start_xmit = ems_usb_start_xmit,
c971fa2a 886 .ndo_change_mtu = can_change_mtu,
702171ad
SH		 887};
888
194b9a4c 889static const struct can_bittiming_const ems_usb_bittiming_const = {
702171ad
SH		 890 .name = "ems_usb",
891 .tseg1_min = 1,
892 .tseg1_max = 16,
893 .tseg2_min = 1,
894 .tseg2_max = 8,
895 .sjw_max = 4,
896 .brp_min = 1,
897 .brp_max = 64,
898 .brp_inc = 1,
899};
900
901static int ems_usb_set_mode(struct net_device *netdev, enum can_mode mode)
902{
903 struct ems_usb *dev = netdev_priv(netdev);
904
702171ad
SH		 905 switch (mode) {
906 case CAN_MODE_START:
907 if (ems_usb_write_mode(dev, SJA1000_MOD_NORMAL))
aabdfd6a 908 netdev_warn(netdev, "couldn't start device");
702171ad
SH		 909
910 if (netif_queue_stopped(netdev))
911 netif_wake_queue(netdev);
912 break;
913
914 default:
915 return -EOPNOTSUPP;
916 }
917
918 return 0;
919}
920
921static int ems_usb_set_bittiming(struct net_device *netdev)
922{
923 struct ems_usb *dev = netdev_priv(netdev);
924 struct can_bittiming *bt = &dev->can.bittiming;
925 u8 btr0, btr1;
926
927 btr0 = ((bt->brp - 1) & 0x3f) | (((bt->sjw - 1) & 0x3) << 6);
928 btr1 = ((bt->prop_seg + bt->phase_seg1 - 1) & 0xf) |
929 (((bt->phase_seg2 - 1) & 0x7) << 4);
930 if (dev->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
931 btr1 |= 0x80;
932
aabdfd6a 933 netdev_info(netdev, "setting BTR0=0x%02x BTR1=0x%02x\n", btr0, btr1);
702171ad
SH		 934
935 dev->active_params.msg.can_params.cc_params.sja1000.btr0 = btr0;
936 dev->active_params.msg.can_params.cc_params.sja1000.btr1 = btr1;
937
938 return ems_usb_command_msg(dev, &dev->active_params);
939}
940
941static void init_params_sja1000(struct ems_cpc_msg *msg)
942{
943 struct cpc_sja1000_params *sja1000 =
944 &msg->msg.can_params.cc_params.sja1000;
945
946 msg->type = CPC_CMD_TYPE_CAN_PARAMS;
947 msg->length = sizeof(struct cpc_can_params);
948 msg->msgid = 0;
949
950 msg->msg.can_params.cc_type = CPC_CC_TYPE_SJA1000;
951
952 /* Acceptance filter open */
953 sja1000->acc_code0 = 0x00;
954 sja1000->acc_code1 = 0x00;
955 sja1000->acc_code2 = 0x00;
956 sja1000->acc_code3 = 0x00;
957
958 /* Acceptance filter open */
959 sja1000->acc_mask0 = 0xFF;
960 sja1000->acc_mask1 = 0xFF;
961 sja1000->acc_mask2 = 0xFF;
962 sja1000->acc_mask3 = 0xFF;
963
964 sja1000->btr0 = 0;
965 sja1000->btr1 = 0;
966
967 sja1000->outp_contr = SJA1000_DEFAULT_OUTPUT_CONTROL;
968 sja1000->mode = SJA1000_MOD_RM;
969}
970
971/*
972 * probe function for new CPC-USB devices
973 */
974static int ems_usb_probe(struct usb_interface *intf,
975 const struct usb_device_id *id)
976{
977 struct net_device *netdev;
978 struct ems_usb *dev;
979 int i, err = -ENOMEM;
980
a6e4bc53 981 netdev = alloc_candev(sizeof(struct ems_usb), MAX_TX_URBS);
702171ad 982 if (!netdev) {
1c0b28b1 983 dev_err(&intf->dev, "ems_usb: Couldn't alloc candev\n");
702171ad
SH		 984 return -ENOMEM;
985 }
986
987 dev = netdev_priv(netdev);
988
989 dev->udev = interface_to_usbdev(intf);
990 dev->netdev = netdev;
991
992 dev->can.state = CAN_STATE_STOPPED;
993 dev->can.clock.freq = EMS_USB_ARM7_CLOCK;
994 dev->can.bittiming_const = &ems_usb_bittiming_const;
995 dev->can.do_set_bittiming = ems_usb_set_bittiming;
996 dev->can.do_set_mode = ems_usb_set_mode;
ad72c347 997 dev->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES;
702171ad 998
702171ad
SH		 999 netdev->netdev_ops = &ems_usb_netdev_ops;
1000
1001 netdev->flags |= IFF_ECHO; /* we support local echo */
1002
1003 init_usb_anchor(&dev->rx_submitted);
1004
1005 init_usb_anchor(&dev->tx_submitted);
1006 atomic_set(&dev->active_tx_urbs, 0);
1007
1008 for (i = 0; i < MAX_TX_URBS; i++)
1009 dev->tx_contexts[i].echo_index = MAX_TX_URBS;
1010
1011 dev->intr_urb = usb_alloc_urb(0, GFP_KERNEL);
1012 if (!dev->intr_urb) {
1c0b28b1 1013 dev_err(&intf->dev, "Couldn't alloc intr URB\n");
702171ad
SH		 1014 goto cleanup_candev;
1015 }
1016
1017 dev->intr_in_buffer = kzalloc(INTR_IN_BUFFER_SIZE, GFP_KERNEL);
09da6c5f 1018 if (!dev->intr_in_buffer)
702171ad 1019 goto cleanup_intr_urb;
702171ad
SH		 1020
1021 dev->tx_msg_buffer = kzalloc(CPC_HEADER_SIZE +
1022 sizeof(struct ems_cpc_msg), GFP_KERNEL);
14f8dc49 1023 if (!dev->tx_msg_buffer)
702171ad 1024 goto cleanup_intr_in_buffer;
702171ad
SH		 1025
1026 usb_set_intfdata(intf, dev);
1027
1028 SET_NETDEV_DEV(netdev, &intf->dev);
1029
1030 init_params_sja1000(&dev->active_params);
1031
1032 err = ems_usb_command_msg(dev, &dev->active_params);
1033 if (err) {
aabdfd6a 1034 netdev_err(netdev, "couldn't initialize controller: %d\n", err);
702171ad
SH		 1035 goto cleanup_tx_msg_buffer;
1036 }
1037
1038 err = register_candev(netdev);
1039 if (err) {
aabdfd6a 1040 netdev_err(netdev, "couldn't register CAN device: %d\n", err);
702171ad
SH		 1041 goto cleanup_tx_msg_buffer;
1042 }
1043
1044 return 0;
1045
1046cleanup_tx_msg_buffer:
1047 kfree(dev->tx_msg_buffer);
1048
1049cleanup_intr_in_buffer:
1050 kfree(dev->intr_in_buffer);
1051
1052cleanup_intr_urb:
1053 usb_free_urb(dev->intr_urb);
1054
1055cleanup_candev:
1056 free_candev(netdev);
1057
1058 return err;
1059}
1060
1061/*
1062 * called by the usb core when the device is removed from the system
1063 */
1064static void ems_usb_disconnect(struct usb_interface *intf)
1065{
1066 struct ems_usb *dev = usb_get_intfdata(intf);
1067
1068 usb_set_intfdata(intf, NULL);
1069
1070 if (dev) {
1071 unregister_netdev(dev->netdev);
1072 free_candev(dev->netdev);
1073
1074 unlink_all_urbs(dev);
1075
1076 usb_free_urb(dev->intr_urb);
1077
1078 kfree(dev->intr_in_buffer);
1079 }
1080}
1081
1082/* usb specific object needed to register this driver with the usb subsystem */
1083static struct usb_driver ems_usb_driver = {
1084 .name = "ems_usb",
1085 .probe = ems_usb_probe,
1086 .disconnect = ems_usb_disconnect,
1087 .id_table = ems_usb_table,
1088};
1089
d632eb1b 1090module_usb_driver(ems_usb_driver);
Linux kernel - Deliverables
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