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Merge branch 'net' of git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux...
[linux-2.6-block.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 */
ba2d3587 200struct __packed ems_cpc_msg {
702171ad
SH		 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:
aabdfd6a 291 netdev_info(netdev, "Rx interrupt aborted %d\n", urb->status);
702171ad
SH		 292 break;
293 }
294
295 err = usb_submit_urb(urb, GFP_ATOMIC);
296
297 if (err == -ENODEV)
298 netif_device_detach(netdev);
299 else if (err)
aabdfd6a 300 netdev_err(netdev, "failed resubmitting intr urb: %d\n", err);
702171ad
SH		 301}
302
303static void ems_usb_rx_can_msg(struct ems_usb *dev, struct ems_cpc_msg *msg)
304{
305 struct can_frame *cf;
306 struct sk_buff *skb;
307 int i;
308 struct net_device_stats *stats = &dev->netdev->stats;
309
7b6856a0 310 skb = alloc_can_skb(dev->netdev, &cf);
702171ad
SH		 311 if (skb == NULL)
312 return;
313
2b2072e9 314 cf->can_id = le32_to_cpu(msg->msg.can_msg.id);
c7cd606f 315 cf->can_dlc = get_can_dlc(msg->msg.can_msg.length & 0xF);
702171ad 316
8e95a202
JP		 317 if (msg->type == CPC_MSG_TYPE_EXT_CAN_FRAME ||
318 msg->type == CPC_MSG_TYPE_EXT_RTR_FRAME)
702171ad
SH		 319 cf->can_id |= CAN_EFF_FLAG;
320
8e95a202
JP		 321 if (msg->type == CPC_MSG_TYPE_RTR_FRAME ||
322 msg->type == CPC_MSG_TYPE_EXT_RTR_FRAME) {
702171ad
SH		 323 cf->can_id |= CAN_RTR_FLAG;
324 } else {
325 for (i = 0; i < cf->can_dlc; i++)
326 cf->data[i] = msg->msg.can_msg.msg[i];
327 }
328
329 netif_rx(skb);
330
331 stats->rx_packets++;
332 stats->rx_bytes += cf->can_dlc;
333}
334
335static void ems_usb_rx_err(struct ems_usb *dev, struct ems_cpc_msg *msg)
336{
337 struct can_frame *cf;
338 struct sk_buff *skb;
339 struct net_device_stats *stats = &dev->netdev->stats;
340
7b6856a0 341 skb = alloc_can_err_skb(dev->netdev, &cf);
702171ad
SH		 342 if (skb == NULL)
343 return;
344
702171ad
SH		 345 if (msg->type == CPC_MSG_TYPE_CAN_STATE) {
346 u8 state = msg->msg.can_state;
347
348 if (state & SJA1000_SR_BS) {
349 dev->can.state = CAN_STATE_BUS_OFF;
350 cf->can_id |= CAN_ERR_BUSOFF;
351
352 can_bus_off(dev->netdev);
353 } else if (state & SJA1000_SR_ES) {
354 dev->can.state = CAN_STATE_ERROR_WARNING;
355 dev->can.can_stats.error_warning++;
356 } else {
357 dev->can.state = CAN_STATE_ERROR_ACTIVE;
358 dev->can.can_stats.error_passive++;
359 }
360 } else if (msg->type == CPC_MSG_TYPE_CAN_FRAME_ERROR) {
361 u8 ecc = msg->msg.error.cc.regs.sja1000.ecc;
362 u8 txerr = msg->msg.error.cc.regs.sja1000.txerr;
363 u8 rxerr = msg->msg.error.cc.regs.sja1000.rxerr;
364
365 /* bus error interrupt */
366 dev->can.can_stats.bus_error++;
367 stats->rx_errors++;
368
369 cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
370
371 switch (ecc & SJA1000_ECC_MASK) {
372 case SJA1000_ECC_BIT:
373 cf->data[2] |= CAN_ERR_PROT_BIT;
374 break;
375 case SJA1000_ECC_FORM:
376 cf->data[2] |= CAN_ERR_PROT_FORM;
377 break;
378 case SJA1000_ECC_STUFF:
379 cf->data[2] |= CAN_ERR_PROT_STUFF;
380 break;
381 default:
382 cf->data[2] |= CAN_ERR_PROT_UNSPEC;
383 cf->data[3] = ecc & SJA1000_ECC_SEG;
384 break;
385 }
386
25985edc 387 /* Error occurred during transmission? */
702171ad
SH		 388 if ((ecc & SJA1000_ECC_DIR) == 0)
389 cf->data[2] |= CAN_ERR_PROT_TX;
390
391 if (dev->can.state == CAN_STATE_ERROR_WARNING ||
392 dev->can.state == CAN_STATE_ERROR_PASSIVE) {
393 cf->data[1] = (txerr > rxerr) ?
394 CAN_ERR_CRTL_TX_PASSIVE : CAN_ERR_CRTL_RX_PASSIVE;
395 }
396 } else if (msg->type == CPC_MSG_TYPE_OVERRUN) {
397 cf->can_id |= CAN_ERR_CRTL;
398 cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
399
400 stats->rx_over_errors++;
401 stats->rx_errors++;
402 }
403
404 netif_rx(skb);
405
406 stats->rx_packets++;
407 stats->rx_bytes += cf->can_dlc;
408}
409
410/*
411 * callback for bulk IN urb
412 */
413static void ems_usb_read_bulk_callback(struct urb *urb)
414{
415 struct ems_usb *dev = urb->context;
416 struct net_device *netdev;
417 int retval;
418
419 netdev = dev->netdev;
420
421 if (!netif_device_present(netdev))
422 return;
423
424 switch (urb->status) {
425 case 0: /* success */
426 break;
427
428 case -ENOENT:
429 return;
430
431 default:
aabdfd6a 432 netdev_info(netdev, "Rx URB aborted (%d)\n", urb->status);
702171ad
SH		 433 goto resubmit_urb;
434 }
435
436 if (urb->actual_length > CPC_HEADER_SIZE) {
437 struct ems_cpc_msg *msg;
438 u8 *ibuf = urb->transfer_buffer;
439 u8 msg_count, again, start;
440
441 msg_count = ibuf[0] & ~0x80;
442 again = ibuf[0] & 0x80;
443
444 start = CPC_HEADER_SIZE;
445
446 while (msg_count) {
447 msg = (struct ems_cpc_msg *)&ibuf[start];
448
449 switch (msg->type) {
450 case CPC_MSG_TYPE_CAN_STATE:
451 /* Process CAN state changes */
452 ems_usb_rx_err(dev, msg);
453 break;
454
455 case CPC_MSG_TYPE_CAN_FRAME:
456 case CPC_MSG_TYPE_EXT_CAN_FRAME:
457 case CPC_MSG_TYPE_RTR_FRAME:
458 case CPC_MSG_TYPE_EXT_RTR_FRAME:
459 ems_usb_rx_can_msg(dev, msg);
460 break;
461
462 case CPC_MSG_TYPE_CAN_FRAME_ERROR:
463 /* Process errorframe */
464 ems_usb_rx_err(dev, msg);
465 break;
466
467 case CPC_MSG_TYPE_OVERRUN:
468 /* Message lost while receiving */
469 ems_usb_rx_err(dev, msg);
470 break;
471 }
472
473 start += CPC_MSG_HEADER_LEN + msg->length;
474 msg_count--;
475
476 if (start > urb->transfer_buffer_length) {
aabdfd6a 477 netdev_err(netdev, "format error\n");
702171ad
SH		 478 break;
479 }
480 }
481 }
482
483resubmit_urb:
484 usb_fill_bulk_urb(urb, dev->udev, usb_rcvbulkpipe(dev->udev, 2),
485 urb->transfer_buffer, RX_BUFFER_SIZE,
486 ems_usb_read_bulk_callback, dev);
487
488 retval = usb_submit_urb(urb, GFP_ATOMIC);
489
490 if (retval == -ENODEV)
491 netif_device_detach(netdev);
492 else if (retval)
aabdfd6a
WG		 493 netdev_err(netdev,
494 "failed resubmitting read bulk urb: %d\n", retval);
702171ad
SH		 495}
496
497/*
498 * callback for bulk IN urb
499 */
500static void ems_usb_write_bulk_callback(struct urb *urb)
501{
502 struct ems_tx_urb_context *context = urb->context;
503 struct ems_usb *dev;
504 struct net_device *netdev;
505
506 BUG_ON(!context);
507
508 dev = context->dev;
509 netdev = dev->netdev;
510
511 /* free up our allocated buffer */
997ea58e
DM		 512 usb_free_coherent(urb->dev, urb->transfer_buffer_length,
513 urb->transfer_buffer, urb->transfer_dma);
702171ad
SH		 514
515 atomic_dec(&dev->active_tx_urbs);
516
517 if (!netif_device_present(netdev))
518 return;
519
520 if (urb->status)
aabdfd6a 521 netdev_info(netdev, "Tx URB aborted (%d)\n", urb->status);
702171ad
SH		 522
523 netdev->trans_start = jiffies;
524
525 /* transmission complete interrupt */
526 netdev->stats.tx_packets++;
527 netdev->stats.tx_bytes += context->dlc;
528
529 can_get_echo_skb(netdev, context->echo_index);
530
531 /* Release context */
532 context->echo_index = MAX_TX_URBS;
533
534 if (netif_queue_stopped(netdev))
535 netif_wake_queue(netdev);
536}
537
538/*
539 * Send the given CPC command synchronously
540 */
541static int ems_usb_command_msg(struct ems_usb *dev, struct ems_cpc_msg *msg)
542{
543 int actual_length;
544
545 /* Copy payload */
546 memcpy(&dev->tx_msg_buffer[CPC_HEADER_SIZE], msg,
547 msg->length + CPC_MSG_HEADER_LEN);
548
549 /* Clear header */
550 memset(&dev->tx_msg_buffer[0], 0, CPC_HEADER_SIZE);
551
552 return usb_bulk_msg(dev->udev, usb_sndbulkpipe(dev->udev, 2),
553 &dev->tx_msg_buffer[0],
554 msg->length + CPC_MSG_HEADER_LEN + CPC_HEADER_SIZE,
555 &actual_length, 1000);
556}
557
558/*
559 * Change CAN controllers' mode register
560 */
561static int ems_usb_write_mode(struct ems_usb *dev, u8 mode)
562{
563 dev->active_params.msg.can_params.cc_params.sja1000.mode = mode;
564
565 return ems_usb_command_msg(dev, &dev->active_params);
566}
567
568/*
569 * Send a CPC_Control command to change behaviour when interface receives a CAN
570 * message, bus error or CAN state changed notifications.
571 */
572static int ems_usb_control_cmd(struct ems_usb *dev, u8 val)
573{
574 struct ems_cpc_msg cmd;
575
576 cmd.type = CPC_CMD_TYPE_CONTROL;
577 cmd.length = CPC_MSG_HEADER_LEN + 1;
578
579 cmd.msgid = 0;
580
581 cmd.msg.generic[0] = val;
582
583 return ems_usb_command_msg(dev, &cmd);
584}
585
586/*
587 * Start interface
588 */
589static int ems_usb_start(struct ems_usb *dev)
590{
591 struct net_device *netdev = dev->netdev;
592 int err, i;
593
594 dev->intr_in_buffer[0] = 0;
595 dev->free_slots = 15; /* initial size */
596
597 for (i = 0; i < MAX_RX_URBS; i++) {
598 struct urb *urb = NULL;
599 u8 *buf = NULL;
600
601 /* create a URB, and a buffer for it */
602 urb = usb_alloc_urb(0, GFP_KERNEL);
603 if (!urb) {
aabdfd6a 604 netdev_err(netdev, "No memory left for URBs\n");
2ee6850c
SH		 605 err = -ENOMEM;
606 break;
702171ad
SH		 607 }
608
997ea58e
DM		 609 buf = usb_alloc_coherent(dev->udev, RX_BUFFER_SIZE, GFP_KERNEL,
610 &urb->transfer_dma);
702171ad 611 if (!buf) {
aabdfd6a 612 netdev_err(netdev, "No memory left for USB buffer\n");
702171ad 613 usb_free_urb(urb);
2ee6850c
SH		 614 err = -ENOMEM;
615 break;
702171ad
SH		 616 }
617
618 usb_fill_bulk_urb(urb, dev->udev, usb_rcvbulkpipe(dev->udev, 2),
619 buf, RX_BUFFER_SIZE,
620 ems_usb_read_bulk_callback, dev);
621 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
622 usb_anchor_urb(urb, &dev->rx_submitted);
623
624 err = usb_submit_urb(urb, GFP_KERNEL);
625 if (err) {
702171ad 626 usb_unanchor_urb(urb);
997ea58e
DM		 627 usb_free_coherent(dev->udev, RX_BUFFER_SIZE, buf,
628 urb->transfer_dma);
702171ad
SH		 629 break;
630 }
631
632 /* Drop reference, USB core will take care of freeing it */
633 usb_free_urb(urb);
634 }
635
636 /* Did we submit any URBs */
637 if (i == 0) {
aabdfd6a 638 netdev_warn(netdev, "couldn't setup read URBs\n");
702171ad
SH		 639 return err;
640 }
641
642 /* Warn if we've couldn't transmit all the URBs */
643 if (i < MAX_RX_URBS)
aabdfd6a 644 netdev_warn(netdev, "rx performance may be slow\n");
702171ad
SH		 645
646 /* Setup and start interrupt URB */
647 usb_fill_int_urb(dev->intr_urb, dev->udev,
648 usb_rcvintpipe(dev->udev, 1),
649 dev->intr_in_buffer,
650 INTR_IN_BUFFER_SIZE,
651 ems_usb_read_interrupt_callback, dev, 1);
652
653 err = usb_submit_urb(dev->intr_urb, GFP_KERNEL);
654 if (err) {
aabdfd6a 655 netdev_warn(netdev, "intr URB submit failed: %d\n", err);
702171ad
SH		 656
657 return err;
658 }
659
660 /* CPC-USB will transfer received message to host */
661 err = ems_usb_control_cmd(dev, CONTR_CAN_MESSAGE | CONTR_CONT_ON);
662 if (err)
663 goto failed;
664
665 /* CPC-USB will transfer CAN state changes to host */
666 err = ems_usb_control_cmd(dev, CONTR_CAN_STATE | CONTR_CONT_ON);
667 if (err)
668 goto failed;
669
670 /* CPC-USB will transfer bus errors to host */
671 err = ems_usb_control_cmd(dev, CONTR_BUS_ERROR | CONTR_CONT_ON);
672 if (err)
673 goto failed;
674
675 err = ems_usb_write_mode(dev, SJA1000_MOD_NORMAL);
676 if (err)
677 goto failed;
678
679 dev->can.state = CAN_STATE_ERROR_ACTIVE;
680
681 return 0;
682
683failed:
aabdfd6a 684 netdev_warn(netdev, "couldn't submit control: %d\n", err);
702171ad
SH		 685
686 return err;
687}
688
689static void unlink_all_urbs(struct ems_usb *dev)
690{
691 int i;
692
693 usb_unlink_urb(dev->intr_urb);
694
695 usb_kill_anchored_urbs(&dev->rx_submitted);
696
697 usb_kill_anchored_urbs(&dev->tx_submitted);
698 atomic_set(&dev->active_tx_urbs, 0);
699
700 for (i = 0; i < MAX_TX_URBS; i++)
701 dev->tx_contexts[i].echo_index = MAX_TX_URBS;
702}
703
704static int ems_usb_open(struct net_device *netdev)
705{
706 struct ems_usb *dev = netdev_priv(netdev);
707 int err;
708
709 err = ems_usb_write_mode(dev, SJA1000_MOD_RM);
710 if (err)
711 return err;
712
713 /* common open */
714 err = open_candev(netdev);
715 if (err)
716 return err;
717
718 /* finally start device */
719 err = ems_usb_start(dev);
720 if (err) {
721 if (err == -ENODEV)
722 netif_device_detach(dev->netdev);
723
aabdfd6a 724 netdev_warn(netdev, "couldn't start device: %d\n", err);
702171ad
SH		 725
726 close_candev(netdev);
727
728 return err;
729 }
730
731 dev->open_time = jiffies;
732
733 netif_start_queue(netdev);
734
735 return 0;
736}
737
738static netdev_tx_t ems_usb_start_xmit(struct sk_buff *skb, struct net_device *netdev)
739{
740 struct ems_usb *dev = netdev_priv(netdev);
741 struct ems_tx_urb_context *context = NULL;
742 struct net_device_stats *stats = &netdev->stats;
743 struct can_frame *cf = (struct can_frame *)skb->data;
744 struct ems_cpc_msg *msg;
745 struct urb *urb;
746 u8 *buf;
747 int i, err;
748 size_t size = CPC_HEADER_SIZE + CPC_MSG_HEADER_LEN
749 + sizeof(struct cpc_can_msg);
750
3ccd4c61
OH		 751 if (can_dropped_invalid_skb(netdev, skb))
752 return NETDEV_TX_OK;
753
702171ad
SH		 754 /* create a URB, and a buffer for it, and copy the data to the URB */
755 urb = usb_alloc_urb(0, GFP_ATOMIC);
756 if (!urb) {
aabdfd6a 757 netdev_err(netdev, "No memory left for URBs\n");
702171ad
SH		 758 goto nomem;
759 }
760
997ea58e 761 buf = usb_alloc_coherent(dev->udev, size, GFP_ATOMIC, &urb->transfer_dma);
702171ad 762 if (!buf) {
aabdfd6a 763 netdev_err(netdev, "No memory left for USB buffer\n");
702171ad
SH		 764 usb_free_urb(urb);
765 goto nomem;
766 }
767
768 msg = (struct ems_cpc_msg *)&buf[CPC_HEADER_SIZE];
769
770 msg->msg.can_msg.id = cf->can_id & CAN_ERR_MASK;
771 msg->msg.can_msg.length = cf->can_dlc;
772
773 if (cf->can_id & CAN_RTR_FLAG) {
774 msg->type = cf->can_id & CAN_EFF_FLAG ?
775 CPC_CMD_TYPE_EXT_RTR_FRAME : CPC_CMD_TYPE_RTR_FRAME;
776
777 msg->length = CPC_CAN_MSG_MIN_SIZE;
778 } else {
779 msg->type = cf->can_id & CAN_EFF_FLAG ?
780 CPC_CMD_TYPE_EXT_CAN_FRAME : CPC_CMD_TYPE_CAN_FRAME;
781
782 for (i = 0; i < cf->can_dlc; i++)
783 msg->msg.can_msg.msg[i] = cf->data[i];
784
785 msg->length = CPC_CAN_MSG_MIN_SIZE + cf->can_dlc;
786 }
787
2b2072e9
SH		 788 /* Respect byte order */
789 msg->msg.can_msg.id = cpu_to_le32(msg->msg.can_msg.id);
790
702171ad
SH		 791 for (i = 0; i < MAX_TX_URBS; i++) {
792 if (dev->tx_contexts[i].echo_index == MAX_TX_URBS) {
793 context = &dev->tx_contexts[i];
794 break;
795 }
796 }
797
798 /*
799 * May never happen! When this happens we'd more URBs in flight as
800 * allowed (MAX_TX_URBS).
801 */
802 if (!context) {
803 usb_unanchor_urb(urb);
997ea58e 804 usb_free_coherent(dev->udev, size, buf, urb->transfer_dma);
702171ad 805
aabdfd6a 806 netdev_warn(netdev, "couldn't find free context\n");
702171ad
SH		 807
808 return NETDEV_TX_BUSY;
809 }
810
811 context->dev = dev;
812 context->echo_index = i;
813 context->dlc = cf->can_dlc;
814
815 usb_fill_bulk_urb(urb, dev->udev, usb_sndbulkpipe(dev->udev, 2), buf,
816 size, ems_usb_write_bulk_callback, context);
817 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
818 usb_anchor_urb(urb, &dev->tx_submitted);
819
820 can_put_echo_skb(skb, netdev, context->echo_index);
821
822 atomic_inc(&dev->active_tx_urbs);
823
824 err = usb_submit_urb(urb, GFP_ATOMIC);
825 if (unlikely(err)) {
826 can_free_echo_skb(netdev, context->echo_index);
827
828 usb_unanchor_urb(urb);
997ea58e 829 usb_free_coherent(dev->udev, size, buf, urb->transfer_dma);
702171ad
SH		 830 dev_kfree_skb(skb);
831
832 atomic_dec(&dev->active_tx_urbs);
833
834 if (err == -ENODEV) {
835 netif_device_detach(netdev);
836 } else {
aabdfd6a 837 netdev_warn(netdev, "failed tx_urb %d\n", err);
702171ad
SH		 838
839 stats->tx_dropped++;
840 }
841 } else {
842 netdev->trans_start = jiffies;
843
844 /* Slow down tx path */
845 if (atomic_read(&dev->active_tx_urbs) >= MAX_TX_URBS ||
846 dev->free_slots < 5) {
847 netif_stop_queue(netdev);
848 }
849 }
850
851 /*
852 * Release our reference to this URB, the USB core will eventually free
853 * it entirely.
854 */
855 usb_free_urb(urb);
856
857 return NETDEV_TX_OK;
858
859nomem:
ea3fb371 860 dev_kfree_skb(skb);
702171ad
SH		 861 stats->tx_dropped++;
862
863 return NETDEV_TX_OK;
864}
865
866static int ems_usb_close(struct net_device *netdev)
867{
868 struct ems_usb *dev = netdev_priv(netdev);
869
870 /* Stop polling */
871 unlink_all_urbs(dev);
872
873 netif_stop_queue(netdev);
874
875 /* Set CAN controller to reset mode */
876 if (ems_usb_write_mode(dev, SJA1000_MOD_RM))
aabdfd6a 877 netdev_warn(netdev, "couldn't stop device");
702171ad
SH		 878
879 close_candev(netdev);
880
881 dev->open_time = 0;
882
883 return 0;
884}
885
886static const struct net_device_ops ems_usb_netdev_ops = {
887 .ndo_open = ems_usb_open,
888 .ndo_stop = ems_usb_close,
889 .ndo_start_xmit = ems_usb_start_xmit,
890};
891
892static struct can_bittiming_const ems_usb_bittiming_const = {
893 .name = "ems_usb",
894 .tseg1_min = 1,
895 .tseg1_max = 16,
896 .tseg2_min = 1,
897 .tseg2_max = 8,
898 .sjw_max = 4,
899 .brp_min = 1,
900 .brp_max = 64,
901 .brp_inc = 1,
902};
903
904static int ems_usb_set_mode(struct net_device *netdev, enum can_mode mode)
905{
906 struct ems_usb *dev = netdev_priv(netdev);
907
908 if (!dev->open_time)
909 return -EINVAL;
910
911 switch (mode) {
912 case CAN_MODE_START:
913 if (ems_usb_write_mode(dev, SJA1000_MOD_NORMAL))
aabdfd6a 914 netdev_warn(netdev, "couldn't start device");
702171ad
SH		 915
916 if (netif_queue_stopped(netdev))
917 netif_wake_queue(netdev);
918 break;
919
920 default:
921 return -EOPNOTSUPP;
922 }
923
924 return 0;
925}
926
927static int ems_usb_set_bittiming(struct net_device *netdev)
928{
929 struct ems_usb *dev = netdev_priv(netdev);
930 struct can_bittiming *bt = &dev->can.bittiming;
931 u8 btr0, btr1;
932
933 btr0 = ((bt->brp - 1) & 0x3f) | (((bt->sjw - 1) & 0x3) << 6);
934 btr1 = ((bt->prop_seg + bt->phase_seg1 - 1) & 0xf) |
935 (((bt->phase_seg2 - 1) & 0x7) << 4);
936 if (dev->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
937 btr1 |= 0x80;
938
aabdfd6a 939 netdev_info(netdev, "setting BTR0=0x%02x BTR1=0x%02x\n", btr0, btr1);
702171ad
SH		 940
941 dev->active_params.msg.can_params.cc_params.sja1000.btr0 = btr0;
942 dev->active_params.msg.can_params.cc_params.sja1000.btr1 = btr1;
943
944 return ems_usb_command_msg(dev, &dev->active_params);
945}
946
947static void init_params_sja1000(struct ems_cpc_msg *msg)
948{
949 struct cpc_sja1000_params *sja1000 =
950 &msg->msg.can_params.cc_params.sja1000;
951
952 msg->type = CPC_CMD_TYPE_CAN_PARAMS;
953 msg->length = sizeof(struct cpc_can_params);
954 msg->msgid = 0;
955
956 msg->msg.can_params.cc_type = CPC_CC_TYPE_SJA1000;
957
958 /* Acceptance filter open */
959 sja1000->acc_code0 = 0x00;
960 sja1000->acc_code1 = 0x00;
961 sja1000->acc_code2 = 0x00;
962 sja1000->acc_code3 = 0x00;
963
964 /* Acceptance filter open */
965 sja1000->acc_mask0 = 0xFF;
966 sja1000->acc_mask1 = 0xFF;
967 sja1000->acc_mask2 = 0xFF;
968 sja1000->acc_mask3 = 0xFF;
969
970 sja1000->btr0 = 0;
971 sja1000->btr1 = 0;
972
973 sja1000->outp_contr = SJA1000_DEFAULT_OUTPUT_CONTROL;
974 sja1000->mode = SJA1000_MOD_RM;
975}
976
977/*
978 * probe function for new CPC-USB devices
979 */
980static int ems_usb_probe(struct usb_interface *intf,
981 const struct usb_device_id *id)
982{
983 struct net_device *netdev;
984 struct ems_usb *dev;
985 int i, err = -ENOMEM;
986
a6e4bc53 987 netdev = alloc_candev(sizeof(struct ems_usb), MAX_TX_URBS);
702171ad 988 if (!netdev) {
1c0b28b1 989 dev_err(&intf->dev, "ems_usb: Couldn't alloc candev\n");
702171ad
SH		 990 return -ENOMEM;
991 }
992
993 dev = netdev_priv(netdev);
994
995 dev->udev = interface_to_usbdev(intf);
996 dev->netdev = netdev;
997
998 dev->can.state = CAN_STATE_STOPPED;
999 dev->can.clock.freq = EMS_USB_ARM7_CLOCK;
1000 dev->can.bittiming_const = &ems_usb_bittiming_const;
1001 dev->can.do_set_bittiming = ems_usb_set_bittiming;
1002 dev->can.do_set_mode = ems_usb_set_mode;
ad72c347 1003 dev->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES;
702171ad 1004
702171ad
SH		 1005 netdev->netdev_ops = &ems_usb_netdev_ops;
1006
1007 netdev->flags |= IFF_ECHO; /* we support local echo */
1008
1009 init_usb_anchor(&dev->rx_submitted);
1010
1011 init_usb_anchor(&dev->tx_submitted);
1012 atomic_set(&dev->active_tx_urbs, 0);
1013
1014 for (i = 0; i < MAX_TX_URBS; i++)
1015 dev->tx_contexts[i].echo_index = MAX_TX_URBS;
1016
1017 dev->intr_urb = usb_alloc_urb(0, GFP_KERNEL);
1018 if (!dev->intr_urb) {
1c0b28b1 1019 dev_err(&intf->dev, "Couldn't alloc intr URB\n");
702171ad
SH		 1020 goto cleanup_candev;
1021 }
1022
1023 dev->intr_in_buffer = kzalloc(INTR_IN_BUFFER_SIZE, GFP_KERNEL);
1024 if (!dev->intr_in_buffer) {
1c0b28b1 1025 dev_err(&intf->dev, "Couldn't alloc Intr buffer\n");
702171ad
SH		 1026 goto cleanup_intr_urb;
1027 }
1028
1029 dev->tx_msg_buffer = kzalloc(CPC_HEADER_SIZE +
1030 sizeof(struct ems_cpc_msg), GFP_KERNEL);
1031 if (!dev->tx_msg_buffer) {
1c0b28b1 1032 dev_err(&intf->dev, "Couldn't alloc Tx buffer\n");
702171ad
SH		 1033 goto cleanup_intr_in_buffer;
1034 }
1035
1036 usb_set_intfdata(intf, dev);
1037
1038 SET_NETDEV_DEV(netdev, &intf->dev);
1039
1040 init_params_sja1000(&dev->active_params);
1041
1042 err = ems_usb_command_msg(dev, &dev->active_params);
1043 if (err) {
aabdfd6a 1044 netdev_err(netdev, "couldn't initialize controller: %d\n", err);
702171ad
SH		 1045 goto cleanup_tx_msg_buffer;
1046 }
1047
1048 err = register_candev(netdev);
1049 if (err) {
aabdfd6a 1050 netdev_err(netdev, "couldn't register CAN device: %d\n", err);
702171ad
SH		 1051 goto cleanup_tx_msg_buffer;
1052 }
1053
1054 return 0;
1055
1056cleanup_tx_msg_buffer:
1057 kfree(dev->tx_msg_buffer);
1058
1059cleanup_intr_in_buffer:
1060 kfree(dev->intr_in_buffer);
1061
1062cleanup_intr_urb:
1063 usb_free_urb(dev->intr_urb);
1064
1065cleanup_candev:
1066 free_candev(netdev);
1067
1068 return err;
1069}
1070
1071/*
1072 * called by the usb core when the device is removed from the system
1073 */
1074static void ems_usb_disconnect(struct usb_interface *intf)
1075{
1076 struct ems_usb *dev = usb_get_intfdata(intf);
1077
1078 usb_set_intfdata(intf, NULL);
1079
1080 if (dev) {
1081 unregister_netdev(dev->netdev);
1082 free_candev(dev->netdev);
1083
1084 unlink_all_urbs(dev);
1085
1086 usb_free_urb(dev->intr_urb);
1087
1088 kfree(dev->intr_in_buffer);
1089 }
1090}
1091
1092/* usb specific object needed to register this driver with the usb subsystem */
1093static struct usb_driver ems_usb_driver = {
1094 .name = "ems_usb",
1095 .probe = ems_usb_probe,
1096 .disconnect = ems_usb_disconnect,
1097 .id_table = ems_usb_table,
1098};
1099
d632eb1b 1100module_usb_driver(ems_usb_driver);
Linux 6.x block layer and io_uring tree(s)