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net: Fix userspace RTM_NEWLINK notifications.
[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 */
19#include <linux/init.h>
20#include <linux/signal.h>
21#include <linux/slab.h>
22#include <linux/module.h>
23#include <linux/netdevice.h>
24#include <linux/usb.h>
25
26#include <linux/can.h>
27#include <linux/can/dev.h>
28#include <linux/can/error.h>
29
30MODULE_AUTHOR("Sebastian Haas <haas@ems-wuensche.com>");
31MODULE_DESCRIPTION("CAN driver for EMS Dr. Thomas Wuensche CAN/USB interfaces");
32MODULE_LICENSE("GPL v2");
33
34/* Control-Values for CPC_Control() Command Subject Selection */
35#define CONTR_CAN_MESSAGE 0x04
36#define CONTR_CAN_STATE 0x0C
37#define CONTR_BUS_ERROR 0x1C
38
39/* Control Command Actions */
40#define CONTR_CONT_OFF 0
41#define CONTR_CONT_ON 1
42#define CONTR_ONCE 2
43
44/* Messages from CPC to PC */
45#define CPC_MSG_TYPE_CAN_FRAME 1 /* CAN data frame */
46#define CPC_MSG_TYPE_RTR_FRAME 8 /* CAN remote frame */
47#define CPC_MSG_TYPE_CAN_PARAMS 12 /* Actual CAN parameters */
48#define CPC_MSG_TYPE_CAN_STATE 14 /* CAN state message */
49#define CPC_MSG_TYPE_EXT_CAN_FRAME 16 /* Extended CAN data frame */
50#define CPC_MSG_TYPE_EXT_RTR_FRAME 17 /* Extended remote frame */
51#define CPC_MSG_TYPE_CONTROL 19 /* change interface behavior */
52#define CPC_MSG_TYPE_CONFIRM 20 /* command processed confirmation */
53#define CPC_MSG_TYPE_OVERRUN 21 /* overrun events */
54#define CPC_MSG_TYPE_CAN_FRAME_ERROR 23 /* detected bus errors */
55#define CPC_MSG_TYPE_ERR_COUNTER 25 /* RX/TX error counter */
56
57/* Messages from the PC to the CPC interface */
58#define CPC_CMD_TYPE_CAN_FRAME 1 /* CAN data frame */
59#define CPC_CMD_TYPE_CONTROL 3 /* control of interface behavior */
60#define CPC_CMD_TYPE_CAN_PARAMS 6 /* set CAN parameters */
61#define CPC_CMD_TYPE_RTR_FRAME 13 /* CAN remote frame */
62#define CPC_CMD_TYPE_CAN_STATE 14 /* CAN state message */
63#define CPC_CMD_TYPE_EXT_CAN_FRAME 15 /* Extended CAN data frame */
64#define CPC_CMD_TYPE_EXT_RTR_FRAME 16 /* Extended CAN remote frame */
65#define CPC_CMD_TYPE_CAN_EXIT 200 /* exit the CAN */
66
67#define CPC_CMD_TYPE_INQ_ERR_COUNTER 25 /* request the CAN error counters */
68#define CPC_CMD_TYPE_CLEAR_MSG_QUEUE 8 /* clear CPC_MSG queue */
69#define CPC_CMD_TYPE_CLEAR_CMD_QUEUE 28 /* clear CPC_CMD queue */
70
71#define CPC_CC_TYPE_SJA1000 2 /* Philips basic CAN controller */
72
73#define CPC_CAN_ECODE_ERRFRAME 0x01 /* Ecode type */
74
75/* Overrun types */
76#define CPC_OVR_EVENT_CAN 0x01
77#define CPC_OVR_EVENT_CANSTATE 0x02
78#define CPC_OVR_EVENT_BUSERROR 0x04
79
80/*
81 * If the CAN controller lost a message we indicate it with the highest bit
82 * set in the count field.
83 */
84#define CPC_OVR_HW 0x80
85
86/* Size of the "struct ems_cpc_msg" without the union */
87#define CPC_MSG_HEADER_LEN 11
88#define CPC_CAN_MSG_MIN_SIZE 5
89
90/* Define these values to match your devices */
91#define USB_CPCUSB_VENDOR_ID 0x12D6
92
93#define USB_CPCUSB_ARM7_PRODUCT_ID 0x0444
94
95/* Mode register NXP LPC2119/SJA1000 CAN Controller */
96#define SJA1000_MOD_NORMAL 0x00
97#define SJA1000_MOD_RM 0x01
98
99/* ECC register NXP LPC2119/SJA1000 CAN Controller */
100#define SJA1000_ECC_SEG 0x1F
101#define SJA1000_ECC_DIR 0x20
102#define SJA1000_ECC_ERR 0x06
103#define SJA1000_ECC_BIT 0x00
104#define SJA1000_ECC_FORM 0x40
105#define SJA1000_ECC_STUFF 0x80
106#define SJA1000_ECC_MASK 0xc0
107
108/* Status register content */
109#define SJA1000_SR_BS 0x80
110#define SJA1000_SR_ES 0x40
111
112#define SJA1000_DEFAULT_OUTPUT_CONTROL 0xDA
113
114/*
115 * The device actually uses a 16MHz clock to generate the CAN clock
116 * but it expects SJA1000 bit settings based on 8MHz (is internally
117 * converted).
118 */
119#define EMS_USB_ARM7_CLOCK 8000000
120
121/*
122 * CAN-Message representation in a CPC_MSG. Message object type is
123 * CPC_MSG_TYPE_CAN_FRAME or CPC_MSG_TYPE_RTR_FRAME or
124 * CPC_MSG_TYPE_EXT_CAN_FRAME or CPC_MSG_TYPE_EXT_RTR_FRAME.
125 */
126struct cpc_can_msg {
127 u32 id;
128 u8 length;
129 u8 msg[8];
130};
131
132/* Representation of the CAN parameters for the SJA1000 controller */
133struct cpc_sja1000_params {
134 u8 mode;
135 u8 acc_code0;
136 u8 acc_code1;
137 u8 acc_code2;
138 u8 acc_code3;
139 u8 acc_mask0;
140 u8 acc_mask1;
141 u8 acc_mask2;
142 u8 acc_mask3;
143 u8 btr0;
144 u8 btr1;
145 u8 outp_contr;
146};
147
148/* CAN params message representation */
149struct cpc_can_params {
150 u8 cc_type;
151
152 /* Will support M16C CAN controller in the future */
153 union {
154 struct cpc_sja1000_params sja1000;
155 } cc_params;
156};
157
158/* Structure for confirmed message handling */
159struct cpc_confirm {
160 u8 error; /* error code */
161};
162
163/* Structure for overrun conditions */
164struct cpc_overrun {
165 u8 event;
166 u8 count;
167};
168
169/* SJA1000 CAN errors (compatible to NXP LPC2119) */
170struct cpc_sja1000_can_error {
171 u8 ecc;
172 u8 rxerr;
173 u8 txerr;
174};
175
176/* structure for CAN error conditions */
177struct cpc_can_error {
178 u8 ecode;
179
180 struct {
181 u8 cc_type;
182
183 /* Other controllers may also provide error code capture regs */
184 union {
185 struct cpc_sja1000_can_error sja1000;
186 } regs;
187 } cc;
188};
189
190/*
191 * Structure containing RX/TX error counter. This structure is used to request
192 * the values of the CAN controllers TX and RX error counter.
193 */
194struct cpc_can_err_counter {
195 u8 rx;
196 u8 tx;
197};
198
199/* Main message type used between library and application */
200struct __attribute__ ((packed)) ems_cpc_msg {
201 u8 type; /* type of message */
202 u8 length; /* length of data within union 'msg' */
203 u8 msgid; /* confirmation handle */
204 u32 ts_sec; /* timestamp in seconds */
205 u32 ts_nsec; /* timestamp in nano seconds */
206
207 union {
208 u8 generic[64];
209 struct cpc_can_msg can_msg;
210 struct cpc_can_params can_params;
211 struct cpc_confirm confirmation;
212 struct cpc_overrun overrun;
213 struct cpc_can_error error;
214 struct cpc_can_err_counter err_counter;
215 u8 can_state;
216 } msg;
217};
218
219/*
220 * Table of devices that work with this driver
221 * NOTE: This driver supports only CPC-USB/ARM7 (LPC2119) yet.
222 */
223static struct usb_device_id ems_usb_table[] = {
224 {USB_DEVICE(USB_CPCUSB_VENDOR_ID, USB_CPCUSB_ARM7_PRODUCT_ID)},
225 {} /* Terminating entry */
226};
227
228MODULE_DEVICE_TABLE(usb, ems_usb_table);
229
230#define RX_BUFFER_SIZE 64
231#define CPC_HEADER_SIZE 4
232#define INTR_IN_BUFFER_SIZE 4
233
234#define MAX_RX_URBS 10
a6e4bc53 235#define MAX_TX_URBS 10
702171ad
SH		 236
237struct ems_usb;
238
239struct ems_tx_urb_context {
240 struct ems_usb *dev;
241
242 u32 echo_index;
243 u8 dlc;
244};
245
246struct ems_usb {
247 struct can_priv can; /* must be the first member */
248 int open_time;
249
250 struct sk_buff *echo_skb[MAX_TX_URBS];
251
252 struct usb_device *udev;
253 struct net_device *netdev;
254
255 atomic_t active_tx_urbs;
256 struct usb_anchor tx_submitted;
257 struct ems_tx_urb_context tx_contexts[MAX_TX_URBS];
258
259 struct usb_anchor rx_submitted;
260
261 struct urb *intr_urb;
262
263 u8 *tx_msg_buffer;
264
265 u8 *intr_in_buffer;
266 unsigned int free_slots; /* remember number of available slots */
267
268 struct ems_cpc_msg active_params; /* active controller parameters */
269};
270
271static void ems_usb_read_interrupt_callback(struct urb *urb)
272{
273 struct ems_usb *dev = urb->context;
274 struct net_device *netdev = dev->netdev;
275 int err;
276
277 if (!netif_device_present(netdev))
278 return;
279
280 switch (urb->status) {
281 case 0:
282 dev->free_slots = dev->intr_in_buffer[1];
283 break;
284
285 case -ECONNRESET: /* unlink */
286 case -ENOENT:
287 case -ESHUTDOWN:
288 return;
289
290 default:
291 dev_info(netdev->dev.parent, "Rx interrupt aborted %d\n",
292 urb->status);
293 break;
294 }
295
296 err = usb_submit_urb(urb, GFP_ATOMIC);
297
298 if (err == -ENODEV)
299 netif_device_detach(netdev);
300 else if (err)
301 dev_err(netdev->dev.parent,
302 "failed resubmitting intr urb: %d\n", err);
303
304 return;
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);
702171ad
SH		 319 cf->can_dlc = min_t(u8, msg->msg.can_msg.length, 8);
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
333 netif_rx(skb);
334
335 stats->rx_packets++;
336 stats->rx_bytes += cf->can_dlc;
337}
338
339static void ems_usb_rx_err(struct ems_usb *dev, struct ems_cpc_msg *msg)
340{
341 struct can_frame *cf;
342 struct sk_buff *skb;
343 struct net_device_stats *stats = &dev->netdev->stats;
344
7b6856a0 345 skb = alloc_can_err_skb(dev->netdev, &cf);
702171ad
SH		 346 if (skb == NULL)
347 return;
348
702171ad
SH		 349 if (msg->type == CPC_MSG_TYPE_CAN_STATE) {
350 u8 state = msg->msg.can_state;
351
352 if (state & SJA1000_SR_BS) {
353 dev->can.state = CAN_STATE_BUS_OFF;
354 cf->can_id |= CAN_ERR_BUSOFF;
355
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:
386 cf->data[2] |= CAN_ERR_PROT_UNSPEC;
387 cf->data[3] = ecc & SJA1000_ECC_SEG;
388 break;
389 }
390
391 /* Error occured during transmission? */
392 if ((ecc & SJA1000_ECC_DIR) == 0)
393 cf->data[2] |= CAN_ERR_PROT_TX;
394
395 if (dev->can.state == CAN_STATE_ERROR_WARNING ||
396 dev->can.state == CAN_STATE_ERROR_PASSIVE) {
397 cf->data[1] = (txerr > rxerr) ?
398 CAN_ERR_CRTL_TX_PASSIVE : CAN_ERR_CRTL_RX_PASSIVE;
399 }
400 } else if (msg->type == CPC_MSG_TYPE_OVERRUN) {
401 cf->can_id |= CAN_ERR_CRTL;
402 cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
403
404 stats->rx_over_errors++;
405 stats->rx_errors++;
406 }
407
408 netif_rx(skb);
409
410 stats->rx_packets++;
411 stats->rx_bytes += cf->can_dlc;
412}
413
414/*
415 * callback for bulk IN urb
416 */
417static void ems_usb_read_bulk_callback(struct urb *urb)
418{
419 struct ems_usb *dev = urb->context;
420 struct net_device *netdev;
421 int retval;
422
423 netdev = dev->netdev;
424
425 if (!netif_device_present(netdev))
426 return;
427
428 switch (urb->status) {
429 case 0: /* success */
430 break;
431
432 case -ENOENT:
433 return;
434
435 default:
436 dev_info(netdev->dev.parent, "Rx URB aborted (%d)\n",
437 urb->status);
438 goto resubmit_urb;
439 }
440
441 if (urb->actual_length > CPC_HEADER_SIZE) {
442 struct ems_cpc_msg *msg;
443 u8 *ibuf = urb->transfer_buffer;
444 u8 msg_count, again, start;
445
446 msg_count = ibuf[0] & ~0x80;
447 again = 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 dev_err(netdev->dev.parent, "format error\n");
483 break;
484 }
485 }
486 }
487
488resubmit_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 dev_err(netdev->dev.parent,
499 "failed resubmitting read bulk urb: %d\n", retval);
500
501 return;
502}
503
504/*
505 * callback for bulk IN urb
506 */
507static void ems_usb_write_bulk_callback(struct urb *urb)
508{
509 struct ems_tx_urb_context *context = urb->context;
510 struct ems_usb *dev;
511 struct net_device *netdev;
512
513 BUG_ON(!context);
514
515 dev = context->dev;
516 netdev = dev->netdev;
517
518 /* free up our allocated buffer */
519 usb_buffer_free(urb->dev, urb->transfer_buffer_length,
520 urb->transfer_buffer, urb->transfer_dma);
521
522 atomic_dec(&dev->active_tx_urbs);
523
524 if (!netif_device_present(netdev))
525 return;
526
527 if (urb->status)
528 dev_info(netdev->dev.parent, "Tx URB aborted (%d)\n",
529 urb->status);
530
531 netdev->trans_start = jiffies;
532
533 /* transmission complete interrupt */
534 netdev->stats.tx_packets++;
535 netdev->stats.tx_bytes += context->dlc;
536
537 can_get_echo_skb(netdev, context->echo_index);
538
539 /* Release context */
540 context->echo_index = MAX_TX_URBS;
541
542 if (netif_queue_stopped(netdev))
543 netif_wake_queue(netdev);
544}
545
546/*
547 * Send the given CPC command synchronously
548 */
549static int ems_usb_command_msg(struct ems_usb *dev, struct ems_cpc_msg *msg)
550{
551 int actual_length;
552
553 /* Copy payload */
554 memcpy(&dev->tx_msg_buffer[CPC_HEADER_SIZE], msg,
555 msg->length + CPC_MSG_HEADER_LEN);
556
557 /* Clear header */
558 memset(&dev->tx_msg_buffer[0], 0, CPC_HEADER_SIZE);
559
560 return usb_bulk_msg(dev->udev, usb_sndbulkpipe(dev->udev, 2),
561 &dev->tx_msg_buffer[0],
562 msg->length + CPC_MSG_HEADER_LEN + CPC_HEADER_SIZE,
563 &actual_length, 1000);
564}
565
566/*
567 * Change CAN controllers' mode register
568 */
569static int ems_usb_write_mode(struct ems_usb *dev, u8 mode)
570{
571 dev->active_params.msg.can_params.cc_params.sja1000.mode = mode;
572
573 return ems_usb_command_msg(dev, &dev->active_params);
574}
575
576/*
577 * Send a CPC_Control command to change behaviour when interface receives a CAN
578 * message, bus error or CAN state changed notifications.
579 */
580static int ems_usb_control_cmd(struct ems_usb *dev, u8 val)
581{
582 struct ems_cpc_msg cmd;
583
584 cmd.type = CPC_CMD_TYPE_CONTROL;
585 cmd.length = CPC_MSG_HEADER_LEN + 1;
586
587 cmd.msgid = 0;
588
589 cmd.msg.generic[0] = val;
590
591 return ems_usb_command_msg(dev, &cmd);
592}
593
594/*
595 * Start interface
596 */
597static int ems_usb_start(struct ems_usb *dev)
598{
599 struct net_device *netdev = dev->netdev;
600 int err, i;
601
602 dev->intr_in_buffer[0] = 0;
603 dev->free_slots = 15; /* initial size */
604
605 for (i = 0; i < MAX_RX_URBS; i++) {
606 struct urb *urb = NULL;
607 u8 *buf = NULL;
608
609 /* create a URB, and a buffer for it */
610 urb = usb_alloc_urb(0, GFP_KERNEL);
611 if (!urb) {
612 dev_err(netdev->dev.parent,
613 "No memory left for URBs\n");
614 return -ENOMEM;
615 }
616
617 buf = usb_buffer_alloc(dev->udev, RX_BUFFER_SIZE, GFP_KERNEL,
618 &urb->transfer_dma);
619 if (!buf) {
620 dev_err(netdev->dev.parent,
621 "No memory left for USB buffer\n");
622 usb_free_urb(urb);
623 return -ENOMEM;
624 }
625
626 usb_fill_bulk_urb(urb, dev->udev, usb_rcvbulkpipe(dev->udev, 2),
627 buf, RX_BUFFER_SIZE,
628 ems_usb_read_bulk_callback, dev);
629 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
630 usb_anchor_urb(urb, &dev->rx_submitted);
631
632 err = usb_submit_urb(urb, GFP_KERNEL);
633 if (err) {
634 if (err == -ENODEV)
635 netif_device_detach(dev->netdev);
636
637 usb_unanchor_urb(urb);
638 usb_buffer_free(dev->udev, RX_BUFFER_SIZE, buf,
639 urb->transfer_dma);
640 break;
641 }
642
643 /* Drop reference, USB core will take care of freeing it */
644 usb_free_urb(urb);
645 }
646
647 /* Did we submit any URBs */
648 if (i == 0) {
649 dev_warn(netdev->dev.parent, "couldn't setup read URBs\n");
650 return err;
651 }
652
653 /* Warn if we've couldn't transmit all the URBs */
654 if (i < MAX_RX_URBS)
655 dev_warn(netdev->dev.parent, "rx performance may be slow\n");
656
657 /* Setup and start interrupt URB */
658 usb_fill_int_urb(dev->intr_urb, dev->udev,
659 usb_rcvintpipe(dev->udev, 1),
660 dev->intr_in_buffer,
661 INTR_IN_BUFFER_SIZE,
662 ems_usb_read_interrupt_callback, dev, 1);
663
664 err = usb_submit_urb(dev->intr_urb, GFP_KERNEL);
665 if (err) {
666 if (err == -ENODEV)
667 netif_device_detach(dev->netdev);
668
669 dev_warn(netdev->dev.parent, "intr URB submit failed: %d\n",
670 err);
671
672 return err;
673 }
674
675 /* CPC-USB will transfer received message to host */
676 err = ems_usb_control_cmd(dev, CONTR_CAN_MESSAGE | CONTR_CONT_ON);
677 if (err)
678 goto failed;
679
680 /* CPC-USB will transfer CAN state changes to host */
681 err = ems_usb_control_cmd(dev, CONTR_CAN_STATE | CONTR_CONT_ON);
682 if (err)
683 goto failed;
684
685 /* CPC-USB will transfer bus errors to host */
686 err = ems_usb_control_cmd(dev, CONTR_BUS_ERROR | CONTR_CONT_ON);
687 if (err)
688 goto failed;
689
690 err = ems_usb_write_mode(dev, SJA1000_MOD_NORMAL);
691 if (err)
692 goto failed;
693
694 dev->can.state = CAN_STATE_ERROR_ACTIVE;
695
696 return 0;
697
698failed:
699 if (err == -ENODEV)
700 netif_device_detach(dev->netdev);
701
702 dev_warn(netdev->dev.parent, "couldn't submit control: %d\n", err);
703
704 return err;
705}
706
707static void unlink_all_urbs(struct ems_usb *dev)
708{
709 int i;
710
711 usb_unlink_urb(dev->intr_urb);
712
713 usb_kill_anchored_urbs(&dev->rx_submitted);
714
715 usb_kill_anchored_urbs(&dev->tx_submitted);
716 atomic_set(&dev->active_tx_urbs, 0);
717
718 for (i = 0; i < MAX_TX_URBS; i++)
719 dev->tx_contexts[i].echo_index = MAX_TX_URBS;
720}
721
722static int ems_usb_open(struct net_device *netdev)
723{
724 struct ems_usb *dev = netdev_priv(netdev);
725 int err;
726
727 err = ems_usb_write_mode(dev, SJA1000_MOD_RM);
728 if (err)
729 return err;
730
731 /* common open */
732 err = open_candev(netdev);
733 if (err)
734 return err;
735
736 /* finally start device */
737 err = ems_usb_start(dev);
738 if (err) {
739 if (err == -ENODEV)
740 netif_device_detach(dev->netdev);
741
742 dev_warn(netdev->dev.parent, "couldn't start device: %d\n",
743 err);
744
745 close_candev(netdev);
746
747 return err;
748 }
749
750 dev->open_time = jiffies;
751
752 netif_start_queue(netdev);
753
754 return 0;
755}
756
757static netdev_tx_t ems_usb_start_xmit(struct sk_buff *skb, struct net_device *netdev)
758{
759 struct ems_usb *dev = netdev_priv(netdev);
760 struct ems_tx_urb_context *context = NULL;
761 struct net_device_stats *stats = &netdev->stats;
762 struct can_frame *cf = (struct can_frame *)skb->data;
763 struct ems_cpc_msg *msg;
764 struct urb *urb;
765 u8 *buf;
766 int i, err;
767 size_t size = CPC_HEADER_SIZE + CPC_MSG_HEADER_LEN
768 + sizeof(struct cpc_can_msg);
769
770 /* create a URB, and a buffer for it, and copy the data to the URB */
771 urb = usb_alloc_urb(0, GFP_ATOMIC);
772 if (!urb) {
773 dev_err(netdev->dev.parent, "No memory left for URBs\n");
774 goto nomem;
775 }
776
777 buf = usb_buffer_alloc(dev->udev, size, GFP_ATOMIC, &urb->transfer_dma);
778 if (!buf) {
779 dev_err(netdev->dev.parent, "No memory left for USB buffer\n");
780 usb_free_urb(urb);
781 goto nomem;
782 }
783
784 msg = (struct ems_cpc_msg *)&buf[CPC_HEADER_SIZE];
785
786 msg->msg.can_msg.id = cf->can_id & CAN_ERR_MASK;
787 msg->msg.can_msg.length = cf->can_dlc;
788
789 if (cf->can_id & CAN_RTR_FLAG) {
790 msg->type = cf->can_id & CAN_EFF_FLAG ?
791 CPC_CMD_TYPE_EXT_RTR_FRAME : CPC_CMD_TYPE_RTR_FRAME;
792
793 msg->length = CPC_CAN_MSG_MIN_SIZE;
794 } else {
795 msg->type = cf->can_id & CAN_EFF_FLAG ?
796 CPC_CMD_TYPE_EXT_CAN_FRAME : CPC_CMD_TYPE_CAN_FRAME;
797
798 for (i = 0; i < cf->can_dlc; i++)
799 msg->msg.can_msg.msg[i] = cf->data[i];
800
801 msg->length = CPC_CAN_MSG_MIN_SIZE + cf->can_dlc;
802 }
803
2b2072e9
SH		 804 /* Respect byte order */
805 msg->msg.can_msg.id = cpu_to_le32(msg->msg.can_msg.id);
806
702171ad
SH		 807 for (i = 0; i < MAX_TX_URBS; i++) {
808 if (dev->tx_contexts[i].echo_index == MAX_TX_URBS) {
809 context = &dev->tx_contexts[i];
810 break;
811 }
812 }
813
814 /*
815 * May never happen! When this happens we'd more URBs in flight as
816 * allowed (MAX_TX_URBS).
817 */
818 if (!context) {
819 usb_unanchor_urb(urb);
820 usb_buffer_free(dev->udev, size, buf, urb->transfer_dma);
821
822 dev_warn(netdev->dev.parent, "couldn't find free context\n");
823
824 return NETDEV_TX_BUSY;
825 }
826
827 context->dev = dev;
828 context->echo_index = i;
829 context->dlc = cf->can_dlc;
830
831 usb_fill_bulk_urb(urb, dev->udev, usb_sndbulkpipe(dev->udev, 2), buf,
832 size, ems_usb_write_bulk_callback, context);
833 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
834 usb_anchor_urb(urb, &dev->tx_submitted);
835
836 can_put_echo_skb(skb, netdev, context->echo_index);
837
838 atomic_inc(&dev->active_tx_urbs);
839
840 err = usb_submit_urb(urb, GFP_ATOMIC);
841 if (unlikely(err)) {
842 can_free_echo_skb(netdev, context->echo_index);
843
844 usb_unanchor_urb(urb);
845 usb_buffer_free(dev->udev, size, buf, urb->transfer_dma);
846 dev_kfree_skb(skb);
847
848 atomic_dec(&dev->active_tx_urbs);
849
850 if (err == -ENODEV) {
851 netif_device_detach(netdev);
852 } else {
853 dev_warn(netdev->dev.parent, "failed tx_urb %d\n", err);
854
855 stats->tx_dropped++;
856 }
857 } else {
858 netdev->trans_start = jiffies;
859
860 /* Slow down tx path */
861 if (atomic_read(&dev->active_tx_urbs) >= MAX_TX_URBS ||
862 dev->free_slots < 5) {
863 netif_stop_queue(netdev);
864 }
865 }
866
867 /*
868 * Release our reference to this URB, the USB core will eventually free
869 * it entirely.
870 */
871 usb_free_urb(urb);
872
873 return NETDEV_TX_OK;
874
875nomem:
876 if (skb)
877 dev_kfree_skb(skb);
878
879 stats->tx_dropped++;
880
881 return NETDEV_TX_OK;
882}
883
884static int ems_usb_close(struct net_device *netdev)
885{
886 struct ems_usb *dev = netdev_priv(netdev);
887
888 /* Stop polling */
889 unlink_all_urbs(dev);
890
891 netif_stop_queue(netdev);
892
893 /* Set CAN controller to reset mode */
894 if (ems_usb_write_mode(dev, SJA1000_MOD_RM))
895 dev_warn(netdev->dev.parent, "couldn't stop device");
896
897 close_candev(netdev);
898
899 dev->open_time = 0;
900
901 return 0;
902}
903
904static const struct net_device_ops ems_usb_netdev_ops = {
905 .ndo_open = ems_usb_open,
906 .ndo_stop = ems_usb_close,
907 .ndo_start_xmit = ems_usb_start_xmit,
908};
909
910static struct can_bittiming_const ems_usb_bittiming_const = {
911 .name = "ems_usb",
912 .tseg1_min = 1,
913 .tseg1_max = 16,
914 .tseg2_min = 1,
915 .tseg2_max = 8,
916 .sjw_max = 4,
917 .brp_min = 1,
918 .brp_max = 64,
919 .brp_inc = 1,
920};
921
922static int ems_usb_set_mode(struct net_device *netdev, enum can_mode mode)
923{
924 struct ems_usb *dev = netdev_priv(netdev);
925
926 if (!dev->open_time)
927 return -EINVAL;
928
929 switch (mode) {
930 case CAN_MODE_START:
931 if (ems_usb_write_mode(dev, SJA1000_MOD_NORMAL))
932 dev_warn(netdev->dev.parent, "couldn't start device");
933
934 if (netif_queue_stopped(netdev))
935 netif_wake_queue(netdev);
936 break;
937
938 default:
939 return -EOPNOTSUPP;
940 }
941
942 return 0;
943}
944
945static int ems_usb_set_bittiming(struct net_device *netdev)
946{
947 struct ems_usb *dev = netdev_priv(netdev);
948 struct can_bittiming *bt = &dev->can.bittiming;
949 u8 btr0, btr1;
950
951 btr0 = ((bt->brp - 1) & 0x3f) | (((bt->sjw - 1) & 0x3) << 6);
952 btr1 = ((bt->prop_seg + bt->phase_seg1 - 1) & 0xf) |
953 (((bt->phase_seg2 - 1) & 0x7) << 4);
954 if (dev->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
955 btr1 |= 0x80;
956
957 dev_info(netdev->dev.parent, "setting BTR0=0x%02x BTR1=0x%02x\n",
958 btr0, btr1);
959
960 dev->active_params.msg.can_params.cc_params.sja1000.btr0 = btr0;
961 dev->active_params.msg.can_params.cc_params.sja1000.btr1 = btr1;
962
963 return ems_usb_command_msg(dev, &dev->active_params);
964}
965
966static void init_params_sja1000(struct ems_cpc_msg *msg)
967{
968 struct cpc_sja1000_params *sja1000 =
969 &msg->msg.can_params.cc_params.sja1000;
970
971 msg->type = CPC_CMD_TYPE_CAN_PARAMS;
972 msg->length = sizeof(struct cpc_can_params);
973 msg->msgid = 0;
974
975 msg->msg.can_params.cc_type = CPC_CC_TYPE_SJA1000;
976
977 /* Acceptance filter open */
978 sja1000->acc_code0 = 0x00;
979 sja1000->acc_code1 = 0x00;
980 sja1000->acc_code2 = 0x00;
981 sja1000->acc_code3 = 0x00;
982
983 /* Acceptance filter open */
984 sja1000->acc_mask0 = 0xFF;
985 sja1000->acc_mask1 = 0xFF;
986 sja1000->acc_mask2 = 0xFF;
987 sja1000->acc_mask3 = 0xFF;
988
989 sja1000->btr0 = 0;
990 sja1000->btr1 = 0;
991
992 sja1000->outp_contr = SJA1000_DEFAULT_OUTPUT_CONTROL;
993 sja1000->mode = SJA1000_MOD_RM;
994}
995
996/*
997 * probe function for new CPC-USB devices
998 */
999static int ems_usb_probe(struct usb_interface *intf,
1000 const struct usb_device_id *id)
1001{
1002 struct net_device *netdev;
1003 struct ems_usb *dev;
1004 int i, err = -ENOMEM;
1005
a6e4bc53 1006 netdev = alloc_candev(sizeof(struct ems_usb), MAX_TX_URBS);
702171ad
SH		 1007 if (!netdev) {
1008 dev_err(netdev->dev.parent, "Couldn't alloc candev\n");
1009 return -ENOMEM;
1010 }
1011
1012 dev = netdev_priv(netdev);
1013
1014 dev->udev = interface_to_usbdev(intf);
1015 dev->netdev = netdev;
1016
1017 dev->can.state = CAN_STATE_STOPPED;
1018 dev->can.clock.freq = EMS_USB_ARM7_CLOCK;
1019 dev->can.bittiming_const = &ems_usb_bittiming_const;
1020 dev->can.do_set_bittiming = ems_usb_set_bittiming;
1021 dev->can.do_set_mode = ems_usb_set_mode;
1022
1023 netdev->flags |= IFF_ECHO; /* we support local echo */
1024
1025 netdev->netdev_ops = &ems_usb_netdev_ops;
1026
1027 netdev->flags |= IFF_ECHO; /* we support local echo */
1028
1029 init_usb_anchor(&dev->rx_submitted);
1030
1031 init_usb_anchor(&dev->tx_submitted);
1032 atomic_set(&dev->active_tx_urbs, 0);
1033
1034 for (i = 0; i < MAX_TX_URBS; i++)
1035 dev->tx_contexts[i].echo_index = MAX_TX_URBS;
1036
1037 dev->intr_urb = usb_alloc_urb(0, GFP_KERNEL);
1038 if (!dev->intr_urb) {
1039 dev_err(netdev->dev.parent, "Couldn't alloc intr URB\n");
1040 goto cleanup_candev;
1041 }
1042
1043 dev->intr_in_buffer = kzalloc(INTR_IN_BUFFER_SIZE, GFP_KERNEL);
1044 if (!dev->intr_in_buffer) {
1045 dev_err(netdev->dev.parent, "Couldn't alloc Intr buffer\n");
1046 goto cleanup_intr_urb;
1047 }
1048
1049 dev->tx_msg_buffer = kzalloc(CPC_HEADER_SIZE +
1050 sizeof(struct ems_cpc_msg), GFP_KERNEL);
1051 if (!dev->tx_msg_buffer) {
1052 dev_err(netdev->dev.parent, "Couldn't alloc Tx buffer\n");
1053 goto cleanup_intr_in_buffer;
1054 }
1055
1056 usb_set_intfdata(intf, dev);
1057
1058 SET_NETDEV_DEV(netdev, &intf->dev);
1059
1060 init_params_sja1000(&dev->active_params);
1061
1062 err = ems_usb_command_msg(dev, &dev->active_params);
1063 if (err) {
1064 dev_err(netdev->dev.parent,
1065 "couldn't initialize controller: %d\n", err);
1066 goto cleanup_tx_msg_buffer;
1067 }
1068
1069 err = register_candev(netdev);
1070 if (err) {
1071 dev_err(netdev->dev.parent,
1072 "couldn't register CAN device: %d\n", err);
1073 goto cleanup_tx_msg_buffer;
1074 }
1075
1076 return 0;
1077
1078cleanup_tx_msg_buffer:
1079 kfree(dev->tx_msg_buffer);
1080
1081cleanup_intr_in_buffer:
1082 kfree(dev->intr_in_buffer);
1083
1084cleanup_intr_urb:
1085 usb_free_urb(dev->intr_urb);
1086
1087cleanup_candev:
1088 free_candev(netdev);
1089
1090 return err;
1091}
1092
1093/*
1094 * called by the usb core when the device is removed from the system
1095 */
1096static void ems_usb_disconnect(struct usb_interface *intf)
1097{
1098 struct ems_usb *dev = usb_get_intfdata(intf);
1099
1100 usb_set_intfdata(intf, NULL);
1101
1102 if (dev) {
1103 unregister_netdev(dev->netdev);
1104 free_candev(dev->netdev);
1105
1106 unlink_all_urbs(dev);
1107
1108 usb_free_urb(dev->intr_urb);
1109
1110 kfree(dev->intr_in_buffer);
1111 }
1112}
1113
1114/* usb specific object needed to register this driver with the usb subsystem */
1115static struct usb_driver ems_usb_driver = {
1116 .name = "ems_usb",
1117 .probe = ems_usb_probe,
1118 .disconnect = ems_usb_disconnect,
1119 .id_table = ems_usb_table,
1120};
1121
1122static int __init ems_usb_init(void)
1123{
1124 int err;
1125
1126 printk(KERN_INFO "CPC-USB kernel driver loaded\n");
1127
1128 /* register this driver with the USB subsystem */
1129 err = usb_register(&ems_usb_driver);
1130
1131 if (err) {
1132 err("usb_register failed. Error number %d\n", err);
1133 return err;
1134 }
1135
1136 return 0;
1137}
1138
1139static void __exit ems_usb_exit(void)
1140{
1141 /* deregister this driver with the USB subsystem */
1142 usb_deregister(&ems_usb_driver);
1143}
1144
1145module_init(ems_usb_init);
1146module_exit(ems_usb_exit);
Linux kernel - Deliverables
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