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Merge remote-tracking branch 'spi/for-next'
[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
90cfde46
GU		 120#define CPC_TX_QUEUE_TRIGGER_LOW 25
121#define CPC_TX_QUEUE_TRIGGER_HIGH 35
122
702171ad
SH		 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 */
128struct cpc_can_msg {
8a4b5b0f 129 __le32 id;
702171ad
SH		 130 u8 length;
131 u8 msg[8];
132};
133
134/* Representation of the CAN parameters for the SJA1000 controller */
135struct 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 */
151struct 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 */
161struct cpc_confirm {
162 u8 error; /* error code */
163};
164
165/* Structure for overrun conditions */
166struct cpc_overrun {
167 u8 event;
168 u8 count;
169};
170
171/* SJA1000 CAN errors (compatible to NXP LPC2119) */
172struct cpc_sja1000_can_error {
173 u8 ecc;
174 u8 rxerr;
175 u8 txerr;
176};
177
178/* structure for CAN error conditions */
179struct 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 */
196struct cpc_can_err_counter {
197 u8 rx;
198 u8 tx;
199};
200
201/* Main message type used between library and application */
ba2d3587 202struct __packed ems_cpc_msg {
702171ad
SH		 203 u8 type; /* type of message */
204 u8 length; /* length of data within union 'msg' */
205 u8 msgid; /* confirmation handle */
a0bc163a
MKB		 206 __le32 ts_sec; /* timestamp in seconds */
207 __le32 ts_nsec; /* timestamp in nano seconds */
702171ad
SH		 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 */
225static struct usb_device_id ems_usb_table[] = {
226 {USB_DEVICE(USB_CPCUSB_VENDOR_ID, USB_CPCUSB_ARM7_PRODUCT_ID)},
227 {} /* Terminating entry */
228};
229
230MODULE_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
a6e4bc53 237#define MAX_TX_URBS 10
702171ad
SH		 238
239struct ems_usb;
240
241struct ems_tx_urb_context {
242 struct ems_usb *dev;
243
244 u32 echo_index;
245 u8 dlc;
246};
247
248struct ems_usb {
249 struct can_priv can; /* must be the first member */
702171ad
SH		 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
272static 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];
59097ac9
MKB		 284 if (dev->free_slots > CPC_TX_QUEUE_TRIGGER_HIGH &&
285 netif_queue_stopped(netdev))
286 netif_wake_queue(netdev);
702171ad
SH		 287 break;
288
289 case -ECONNRESET: /* unlink */
290 case -ENOENT:
291 case -ESHUTDOWN:
292 return;
293
294 default:
aabdfd6a 295 netdev_info(netdev, "Rx interrupt aborted %d\n", urb->status);
702171ad
SH		 296 break;
297 }
298
299 err = usb_submit_urb(urb, GFP_ATOMIC);
300
301 if (err == -ENODEV)
302 netif_device_detach(netdev);
303 else if (err)
aabdfd6a 304 netdev_err(netdev, "failed resubmitting intr urb: %d\n", err);
702171ad
SH		 305}
306
307static void ems_usb_rx_can_msg(struct ems_usb *dev, struct ems_cpc_msg *msg)
308{
309 struct can_frame *cf;
310 struct sk_buff *skb;
311 int i;
312 struct net_device_stats *stats = &dev->netdev->stats;
313
7b6856a0 314 skb = alloc_can_skb(dev->netdev, &cf);
702171ad
SH		 315 if (skb == NULL)
316 return;
317
2b2072e9 318 cf->can_id = le32_to_cpu(msg->msg.can_msg.id);
c7cd606f 319 cf->can_dlc = get_can_dlc(msg->msg.can_msg.length & 0xF);
702171ad 320
8e95a202
JP		 321 if (msg->type == CPC_MSG_TYPE_EXT_CAN_FRAME ||
322 msg->type == CPC_MSG_TYPE_EXT_RTR_FRAME)
702171ad
SH		 323 cf->can_id |= CAN_EFF_FLAG;
324
8e95a202
JP		 325 if (msg->type == CPC_MSG_TYPE_RTR_FRAME ||
326 msg->type == CPC_MSG_TYPE_EXT_RTR_FRAME) {
702171ad
SH		 327 cf->can_id |= CAN_RTR_FLAG;
328 } else {
329 for (i = 0; i < cf->can_dlc; i++)
330 cf->data[i] = msg->msg.can_msg.msg[i];
331 }
332
702171ad
SH		 333 stats->rx_packets++;
334 stats->rx_bytes += cf->can_dlc;
43c021e8 335 netif_rx(skb);
702171ad
SH		 336}
337
338static void ems_usb_rx_err(struct ems_usb *dev, struct ems_cpc_msg *msg)
339{
340 struct can_frame *cf;
341 struct sk_buff *skb;
342 struct net_device_stats *stats = &dev->netdev->stats;
343
7b6856a0 344 skb = alloc_can_err_skb(dev->netdev, &cf);
702171ad
SH		 345 if (skb == NULL)
346 return;
347
702171ad
SH		 348 if (msg->type == CPC_MSG_TYPE_CAN_STATE) {
349 u8 state = msg->msg.can_state;
350
351 if (state & SJA1000_SR_BS) {
352 dev->can.state = CAN_STATE_BUS_OFF;
353 cf->can_id |= CAN_ERR_BUSOFF;
354
be38a6f9 355 dev->can.can_stats.bus_off++;
702171ad
SH		 356 can_bus_off(dev->netdev);
357 } else if (state & SJA1000_SR_ES) {
358 dev->can.state = CAN_STATE_ERROR_WARNING;
359 dev->can.can_stats.error_warning++;
360 } else {
361 dev->can.state = CAN_STATE_ERROR_ACTIVE;
362 dev->can.can_stats.error_passive++;
363 }
364 } else if (msg->type == CPC_MSG_TYPE_CAN_FRAME_ERROR) {
365 u8 ecc = msg->msg.error.cc.regs.sja1000.ecc;
366 u8 txerr = msg->msg.error.cc.regs.sja1000.txerr;
367 u8 rxerr = msg->msg.error.cc.regs.sja1000.rxerr;
368
369 /* bus error interrupt */
370 dev->can.can_stats.bus_error++;
371 stats->rx_errors++;
372
373 cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
374
375 switch (ecc & SJA1000_ECC_MASK) {
376 case SJA1000_ECC_BIT:
377 cf->data[2] |= CAN_ERR_PROT_BIT;
378 break;
379 case SJA1000_ECC_FORM:
380 cf->data[2] |= CAN_ERR_PROT_FORM;
381 break;
382 case SJA1000_ECC_STUFF:
383 cf->data[2] |= CAN_ERR_PROT_STUFF;
384 break;
385 default:
702171ad
SH		 386 cf->data[3] = ecc & SJA1000_ECC_SEG;
387 break;
388 }
389
25985edc 390 /* Error occurred during transmission? */
702171ad
SH		 391 if ((ecc & SJA1000_ECC_DIR) == 0)
392 cf->data[2] |= CAN_ERR_PROT_TX;
393
394 if (dev->can.state == CAN_STATE_ERROR_WARNING ||
395 dev->can.state == CAN_STATE_ERROR_PASSIVE) {
396 cf->data[1] = (txerr > rxerr) ?
397 CAN_ERR_CRTL_TX_PASSIVE : CAN_ERR_CRTL_RX_PASSIVE;
398 }
399 } else if (msg->type == CPC_MSG_TYPE_OVERRUN) {
400 cf->can_id |= CAN_ERR_CRTL;
401 cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
402
403 stats->rx_over_errors++;
404 stats->rx_errors++;
405 }
406
702171ad
SH		 407 stats->rx_packets++;
408 stats->rx_bytes += cf->can_dlc;
43c021e8 409 netif_rx(skb);
702171ad
SH		 410}
411
412/*
413 * callback for bulk IN urb
414 */
415static void ems_usb_read_bulk_callback(struct urb *urb)
416{
417 struct ems_usb *dev = urb->context;
418 struct net_device *netdev;
419 int retval;
420
421 netdev = dev->netdev;
422
423 if (!netif_device_present(netdev))
424 return;
425
426 switch (urb->status) {
427 case 0: /* success */
428 break;
429
430 case -ENOENT:
431 return;
432
433 default:
aabdfd6a 434 netdev_info(netdev, "Rx URB aborted (%d)\n", urb->status);
702171ad
SH		 435 goto resubmit_urb;
436 }
437
438 if (urb->actual_length > CPC_HEADER_SIZE) {
439 struct ems_cpc_msg *msg;
440 u8 *ibuf = urb->transfer_buffer;
4e2061b1 441 u8 msg_count, start;
702171ad
SH		 442
443 msg_count = ibuf[0] & ~0x80;
702171ad
SH		 444
445 start = CPC_HEADER_SIZE;
446
447 while (msg_count) {
448 msg = (struct ems_cpc_msg *)&ibuf[start];
449
450 switch (msg->type) {
451 case CPC_MSG_TYPE_CAN_STATE:
452 /* Process CAN state changes */
453 ems_usb_rx_err(dev, msg);
454 break;
455
456 case CPC_MSG_TYPE_CAN_FRAME:
457 case CPC_MSG_TYPE_EXT_CAN_FRAME:
458 case CPC_MSG_TYPE_RTR_FRAME:
459 case CPC_MSG_TYPE_EXT_RTR_FRAME:
460 ems_usb_rx_can_msg(dev, msg);
461 break;
462
463 case CPC_MSG_TYPE_CAN_FRAME_ERROR:
464 /* Process errorframe */
465 ems_usb_rx_err(dev, msg);
466 break;
467
468 case CPC_MSG_TYPE_OVERRUN:
469 /* Message lost while receiving */
470 ems_usb_rx_err(dev, msg);
471 break;
472 }
473
474 start += CPC_MSG_HEADER_LEN + msg->length;
475 msg_count--;
476
477 if (start > urb->transfer_buffer_length) {
aabdfd6a 478 netdev_err(netdev, "format error\n");
702171ad
SH		 479 break;
480 }
481 }
482 }
483
484resubmit_urb:
485 usb_fill_bulk_urb(urb, dev->udev, usb_rcvbulkpipe(dev->udev, 2),
486 urb->transfer_buffer, RX_BUFFER_SIZE,
487 ems_usb_read_bulk_callback, dev);
488
489 retval = usb_submit_urb(urb, GFP_ATOMIC);
490
491 if (retval == -ENODEV)
492 netif_device_detach(netdev);
493 else if (retval)
aabdfd6a
WG		 494 netdev_err(netdev,
495 "failed resubmitting read bulk urb: %d\n", retval);
702171ad
SH		 496}
497
498/*
499 * callback for bulk IN urb
500 */
501static void ems_usb_write_bulk_callback(struct urb *urb)
502{
503 struct ems_tx_urb_context *context = urb->context;
504 struct ems_usb *dev;
505 struct net_device *netdev;
506
507 BUG_ON(!context);
508
509 dev = context->dev;
510 netdev = dev->netdev;
511
512 /* free up our allocated buffer */
997ea58e
DM		 513 usb_free_coherent(urb->dev, urb->transfer_buffer_length,
514 urb->transfer_buffer, urb->transfer_dma);
702171ad
SH		 515
516 atomic_dec(&dev->active_tx_urbs);
517
518 if (!netif_device_present(netdev))
519 return;
520
521 if (urb->status)
aabdfd6a 522 netdev_info(netdev, "Tx URB aborted (%d)\n", urb->status);
702171ad 523
860e9538 524 netif_trans_update(netdev);
702171ad
SH		 525
526 /* transmission complete interrupt */
527 netdev->stats.tx_packets++;
528 netdev->stats.tx_bytes += context->dlc;
529
530 can_get_echo_skb(netdev, context->echo_index);
531
532 /* Release context */
533 context->echo_index = MAX_TX_URBS;
534
702171ad
SH		 535}
536
537/*
538 * Send the given CPC command synchronously
539 */
540static int ems_usb_command_msg(struct ems_usb *dev, struct ems_cpc_msg *msg)
541{
542 int actual_length;
543
544 /* Copy payload */
545 memcpy(&dev->tx_msg_buffer[CPC_HEADER_SIZE], msg,
546 msg->length + CPC_MSG_HEADER_LEN);
547
548 /* Clear header */
549 memset(&dev->tx_msg_buffer[0], 0, CPC_HEADER_SIZE);
550
551 return usb_bulk_msg(dev->udev, usb_sndbulkpipe(dev->udev, 2),
552 &dev->tx_msg_buffer[0],
553 msg->length + CPC_MSG_HEADER_LEN + CPC_HEADER_SIZE,
554 &actual_length, 1000);
555}
556
557/*
558 * Change CAN controllers' mode register
559 */
560static int ems_usb_write_mode(struct ems_usb *dev, u8 mode)
561{
562 dev->active_params.msg.can_params.cc_params.sja1000.mode = mode;
563
564 return ems_usb_command_msg(dev, &dev->active_params);
565}
566
567/*
568 * Send a CPC_Control command to change behaviour when interface receives a CAN
569 * message, bus error or CAN state changed notifications.
570 */
571static int ems_usb_control_cmd(struct ems_usb *dev, u8 val)
572{
573 struct ems_cpc_msg cmd;
574
575 cmd.type = CPC_CMD_TYPE_CONTROL;
576 cmd.length = CPC_MSG_HEADER_LEN + 1;
577
578 cmd.msgid = 0;
579
580 cmd.msg.generic[0] = val;
581
582 return ems_usb_command_msg(dev, &cmd);
583}
584
585/*
586 * Start interface
587 */
588static int ems_usb_start(struct ems_usb *dev)
589{
590 struct net_device *netdev = dev->netdev;
591 int err, i;
592
593 dev->intr_in_buffer[0] = 0;
90cfde46 594 dev->free_slots = 50; /* initial size */
702171ad
SH		 595
596 for (i = 0; i < MAX_RX_URBS; i++) {
597 struct urb *urb = NULL;
598 u8 *buf = NULL;
599
600 /* create a URB, and a buffer for it */
601 urb = usb_alloc_urb(0, GFP_KERNEL);
602 if (!urb) {
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);
87ced2f9 754 if (!urb)
702171ad 755 goto nomem;
702171ad 756
997ea58e 757 buf = usb_alloc_coherent(dev->udev, size, GFP_ATOMIC, &urb->transfer_dma);
702171ad 758 if (!buf) {
aabdfd6a 759 netdev_err(netdev, "No memory left for USB buffer\n");
702171ad
SH		 760 usb_free_urb(urb);
761 goto nomem;
762 }
763
764 msg = (struct ems_cpc_msg *)&buf[CPC_HEADER_SIZE];
765
8a4b5b0f 766 msg->msg.can_msg.id = cpu_to_le32(cf->can_id & CAN_ERR_MASK);
702171ad
SH		 767 msg->msg.can_msg.length = cf->can_dlc;
768
769 if (cf->can_id & CAN_RTR_FLAG) {
770 msg->type = cf->can_id & CAN_EFF_FLAG ?
771 CPC_CMD_TYPE_EXT_RTR_FRAME : CPC_CMD_TYPE_RTR_FRAME;
772
773 msg->length = CPC_CAN_MSG_MIN_SIZE;
774 } else {
775 msg->type = cf->can_id & CAN_EFF_FLAG ?
776 CPC_CMD_TYPE_EXT_CAN_FRAME : CPC_CMD_TYPE_CAN_FRAME;
777
778 for (i = 0; i < cf->can_dlc; i++)
779 msg->msg.can_msg.msg[i] = cf->data[i];
780
781 msg->length = CPC_CAN_MSG_MIN_SIZE + cf->can_dlc;
782 }
783
784 for (i = 0; i < MAX_TX_URBS; i++) {
785 if (dev->tx_contexts[i].echo_index == MAX_TX_URBS) {
786 context = &dev->tx_contexts[i];
787 break;
788 }
789 }
790
791 /*
792 * May never happen! When this happens we'd more URBs in flight as
793 * allowed (MAX_TX_URBS).
794 */
795 if (!context) {
997ea58e 796 usb_free_coherent(dev->udev, size, buf, urb->transfer_dma);
a1c31f1d 797 usb_free_urb(urb);
702171ad 798
aabdfd6a 799 netdev_warn(netdev, "couldn't find free context\n");
702171ad
SH		 800
801 return NETDEV_TX_BUSY;
802 }
803
804 context->dev = dev;
805 context->echo_index = i;
806 context->dlc = cf->can_dlc;
807
808 usb_fill_bulk_urb(urb, dev->udev, usb_sndbulkpipe(dev->udev, 2), buf,
809 size, ems_usb_write_bulk_callback, context);
810 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
811 usb_anchor_urb(urb, &dev->tx_submitted);
812
813 can_put_echo_skb(skb, netdev, context->echo_index);
814
815 atomic_inc(&dev->active_tx_urbs);
816
817 err = usb_submit_urb(urb, GFP_ATOMIC);
818 if (unlikely(err)) {
819 can_free_echo_skb(netdev, context->echo_index);
820
821 usb_unanchor_urb(urb);
997ea58e 822 usb_free_coherent(dev->udev, size, buf, urb->transfer_dma);
702171ad
SH		 823 dev_kfree_skb(skb);
824
825 atomic_dec(&dev->active_tx_urbs);
826
827 if (err == -ENODEV) {
828 netif_device_detach(netdev);
829 } else {
aabdfd6a 830 netdev_warn(netdev, "failed tx_urb %d\n", err);
702171ad
SH		 831
832 stats->tx_dropped++;
833 }
834 } else {
860e9538 835 netif_trans_update(netdev);
702171ad
SH		 836
837 /* Slow down tx path */
838 if (atomic_read(&dev->active_tx_urbs) >= MAX_TX_URBS ||
90cfde46 839 dev->free_slots < CPC_TX_QUEUE_TRIGGER_LOW) {
702171ad
SH		 840 netif_stop_queue(netdev);
841 }
842 }
843
844 /*
845 * Release our reference to this URB, the USB core will eventually free
846 * it entirely.
847 */
848 usb_free_urb(urb);
849
850 return NETDEV_TX_OK;
851
852nomem:
ea3fb371 853 dev_kfree_skb(skb);
702171ad
SH		 854 stats->tx_dropped++;
855
856 return NETDEV_TX_OK;
857}
858
859static int ems_usb_close(struct net_device *netdev)
860{
861 struct ems_usb *dev = netdev_priv(netdev);
862
863 /* Stop polling */
864 unlink_all_urbs(dev);
865
866 netif_stop_queue(netdev);
867
868 /* Set CAN controller to reset mode */
869 if (ems_usb_write_mode(dev, SJA1000_MOD_RM))
aabdfd6a 870 netdev_warn(netdev, "couldn't stop device");
702171ad
SH		 871
872 close_candev(netdev);
873
702171ad
SH		 874 return 0;
875}
876
877static const struct net_device_ops ems_usb_netdev_ops = {
878 .ndo_open = ems_usb_open,
879 .ndo_stop = ems_usb_close,
880 .ndo_start_xmit = ems_usb_start_xmit,
c971fa2a 881 .ndo_change_mtu = can_change_mtu,
702171ad
SH		 882};
883
194b9a4c 884static const struct can_bittiming_const ems_usb_bittiming_const = {
702171ad
SH		 885 .name = "ems_usb",
886 .tseg1_min = 1,
887 .tseg1_max = 16,
888 .tseg2_min = 1,
889 .tseg2_max = 8,
890 .sjw_max = 4,
891 .brp_min = 1,
892 .brp_max = 64,
893 .brp_inc = 1,
894};
895
896static int ems_usb_set_mode(struct net_device *netdev, enum can_mode mode)
897{
898 struct ems_usb *dev = netdev_priv(netdev);
899
702171ad
SH		 900 switch (mode) {
901 case CAN_MODE_START:
902 if (ems_usb_write_mode(dev, SJA1000_MOD_NORMAL))
aabdfd6a 903 netdev_warn(netdev, "couldn't start device");
702171ad
SH		 904
905 if (netif_queue_stopped(netdev))
906 netif_wake_queue(netdev);
907 break;
908
909 default:
910 return -EOPNOTSUPP;
911 }
912
913 return 0;
914}
915
916static int ems_usb_set_bittiming(struct net_device *netdev)
917{
918 struct ems_usb *dev = netdev_priv(netdev);
919 struct can_bittiming *bt = &dev->can.bittiming;
920 u8 btr0, btr1;
921
922 btr0 = ((bt->brp - 1) & 0x3f) | (((bt->sjw - 1) & 0x3) << 6);
923 btr1 = ((bt->prop_seg + bt->phase_seg1 - 1) & 0xf) |
924 (((bt->phase_seg2 - 1) & 0x7) << 4);
925 if (dev->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
926 btr1 |= 0x80;
927
aabdfd6a 928 netdev_info(netdev, "setting BTR0=0x%02x BTR1=0x%02x\n", btr0, btr1);
702171ad
SH		 929
930 dev->active_params.msg.can_params.cc_params.sja1000.btr0 = btr0;
931 dev->active_params.msg.can_params.cc_params.sja1000.btr1 = btr1;
932
933 return ems_usb_command_msg(dev, &dev->active_params);
934}
935
936static void init_params_sja1000(struct ems_cpc_msg *msg)
937{
938 struct cpc_sja1000_params *sja1000 =
939 &msg->msg.can_params.cc_params.sja1000;
940
941 msg->type = CPC_CMD_TYPE_CAN_PARAMS;
942 msg->length = sizeof(struct cpc_can_params);
943 msg->msgid = 0;
944
945 msg->msg.can_params.cc_type = CPC_CC_TYPE_SJA1000;
946
947 /* Acceptance filter open */
948 sja1000->acc_code0 = 0x00;
949 sja1000->acc_code1 = 0x00;
950 sja1000->acc_code2 = 0x00;
951 sja1000->acc_code3 = 0x00;
952
953 /* Acceptance filter open */
954 sja1000->acc_mask0 = 0xFF;
955 sja1000->acc_mask1 = 0xFF;
956 sja1000->acc_mask2 = 0xFF;
957 sja1000->acc_mask3 = 0xFF;
958
959 sja1000->btr0 = 0;
960 sja1000->btr1 = 0;
961
962 sja1000->outp_contr = SJA1000_DEFAULT_OUTPUT_CONTROL;
963 sja1000->mode = SJA1000_MOD_RM;
964}
965
966/*
967 * probe function for new CPC-USB devices
968 */
969static int ems_usb_probe(struct usb_interface *intf,
970 const struct usb_device_id *id)
971{
972 struct net_device *netdev;
973 struct ems_usb *dev;
974 int i, err = -ENOMEM;
975
a6e4bc53 976 netdev = alloc_candev(sizeof(struct ems_usb), MAX_TX_URBS);
702171ad 977 if (!netdev) {
1c0b28b1 978 dev_err(&intf->dev, "ems_usb: Couldn't alloc candev\n");
702171ad
SH		 979 return -ENOMEM;
980 }
981
982 dev = netdev_priv(netdev);
983
984 dev->udev = interface_to_usbdev(intf);
985 dev->netdev = netdev;
986
987 dev->can.state = CAN_STATE_STOPPED;
988 dev->can.clock.freq = EMS_USB_ARM7_CLOCK;
989 dev->can.bittiming_const = &ems_usb_bittiming_const;
990 dev->can.do_set_bittiming = ems_usb_set_bittiming;
991 dev->can.do_set_mode = ems_usb_set_mode;
ad72c347 992 dev->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES;
702171ad 993
702171ad
SH		 994 netdev->netdev_ops = &ems_usb_netdev_ops;
995
996 netdev->flags |= IFF_ECHO; /* we support local echo */
997
998 init_usb_anchor(&dev->rx_submitted);
999
1000 init_usb_anchor(&dev->tx_submitted);
1001 atomic_set(&dev->active_tx_urbs, 0);
1002
1003 for (i = 0; i < MAX_TX_URBS; i++)
1004 dev->tx_contexts[i].echo_index = MAX_TX_URBS;
1005
1006 dev->intr_urb = usb_alloc_urb(0, GFP_KERNEL);
87ced2f9 1007 if (!dev->intr_urb)
702171ad 1008 goto cleanup_candev;
702171ad
SH		 1009
1010 dev->intr_in_buffer = kzalloc(INTR_IN_BUFFER_SIZE, GFP_KERNEL);
09da6c5f 1011 if (!dev->intr_in_buffer)
702171ad 1012 goto cleanup_intr_urb;
702171ad
SH		 1013
1014 dev->tx_msg_buffer = kzalloc(CPC_HEADER_SIZE +
1015 sizeof(struct ems_cpc_msg), GFP_KERNEL);
14f8dc49 1016 if (!dev->tx_msg_buffer)
702171ad 1017 goto cleanup_intr_in_buffer;
702171ad
SH		 1018
1019 usb_set_intfdata(intf, dev);
1020
1021 SET_NETDEV_DEV(netdev, &intf->dev);
1022
1023 init_params_sja1000(&dev->active_params);
1024
1025 err = ems_usb_command_msg(dev, &dev->active_params);
1026 if (err) {
aabdfd6a 1027 netdev_err(netdev, "couldn't initialize controller: %d\n", err);
702171ad
SH		 1028 goto cleanup_tx_msg_buffer;
1029 }
1030
1031 err = register_candev(netdev);
1032 if (err) {
aabdfd6a 1033 netdev_err(netdev, "couldn't register CAN device: %d\n", err);
702171ad
SH		 1034 goto cleanup_tx_msg_buffer;
1035 }
1036
1037 return 0;
1038
1039cleanup_tx_msg_buffer:
1040 kfree(dev->tx_msg_buffer);
1041
1042cleanup_intr_in_buffer:
1043 kfree(dev->intr_in_buffer);
1044
1045cleanup_intr_urb:
1046 usb_free_urb(dev->intr_urb);
1047
1048cleanup_candev:
1049 free_candev(netdev);
1050
1051 return err;
1052}
1053
1054/*
1055 * called by the usb core when the device is removed from the system
1056 */
1057static void ems_usb_disconnect(struct usb_interface *intf)
1058{
1059 struct ems_usb *dev = usb_get_intfdata(intf);
1060
1061 usb_set_intfdata(intf, NULL);
1062
1063 if (dev) {
1064 unregister_netdev(dev->netdev);
1065 free_candev(dev->netdev);
1066
1067 unlink_all_urbs(dev);
1068
1069 usb_free_urb(dev->intr_urb);
1070
1071 kfree(dev->intr_in_buffer);
1072 }
1073}
1074
1075/* usb specific object needed to register this driver with the usb subsystem */
1076static struct usb_driver ems_usb_driver = {
1077 .name = "ems_usb",
1078 .probe = ems_usb_probe,
1079 .disconnect = ems_usb_disconnect,
1080 .id_table = ems_usb_table,
1081};
1082
d632eb1b 1083module_usb_driver(ems_usb_driver);
Linux kernel - Deliverables
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