]>
Commit | Line | Data |
---|---|---|
1 | // SPDX-License-Identifier: GPL-2.0-only | |
2 | /* | |
3 | * CAN driver for EMS Dr. Thomas Wuensche CPC-USB/ARM7 | |
4 | * | |
5 | * Copyright (C) 2004-2009 EMS Dr. Thomas Wuensche | |
6 | */ | |
7 | #include <linux/signal.h> | |
8 | #include <linux/slab.h> | |
9 | #include <linux/module.h> | |
10 | #include <linux/netdevice.h> | |
11 | #include <linux/usb.h> | |
12 | ||
13 | #include <linux/can.h> | |
14 | #include <linux/can/dev.h> | |
15 | #include <linux/can/error.h> | |
16 | ||
17 | MODULE_AUTHOR("Sebastian Haas <haas@ems-wuensche.com>"); | |
18 | MODULE_DESCRIPTION("CAN driver for EMS Dr. Thomas Wuensche CAN/USB interfaces"); | |
19 | MODULE_LICENSE("GPL v2"); | |
20 | ||
21 | /* Control-Values for CPC_Control() Command Subject Selection */ | |
22 | #define CONTR_CAN_MESSAGE 0x04 | |
23 | #define CONTR_CAN_STATE 0x0C | |
24 | #define CONTR_BUS_ERROR 0x1C | |
25 | ||
26 | /* Control Command Actions */ | |
27 | #define CONTR_CONT_OFF 0 | |
28 | #define CONTR_CONT_ON 1 | |
29 | #define CONTR_ONCE 2 | |
30 | ||
31 | /* Messages from CPC to PC */ | |
32 | #define CPC_MSG_TYPE_CAN_FRAME 1 /* CAN data frame */ | |
33 | #define CPC_MSG_TYPE_RTR_FRAME 8 /* CAN remote frame */ | |
34 | #define CPC_MSG_TYPE_CAN_PARAMS 12 /* Actual CAN parameters */ | |
35 | #define CPC_MSG_TYPE_CAN_STATE 14 /* CAN state message */ | |
36 | #define CPC_MSG_TYPE_EXT_CAN_FRAME 16 /* Extended CAN data frame */ | |
37 | #define CPC_MSG_TYPE_EXT_RTR_FRAME 17 /* Extended remote frame */ | |
38 | #define CPC_MSG_TYPE_CONTROL 19 /* change interface behavior */ | |
39 | #define CPC_MSG_TYPE_CONFIRM 20 /* command processed confirmation */ | |
40 | #define CPC_MSG_TYPE_OVERRUN 21 /* overrun events */ | |
41 | #define CPC_MSG_TYPE_CAN_FRAME_ERROR 23 /* detected bus errors */ | |
42 | #define CPC_MSG_TYPE_ERR_COUNTER 25 /* RX/TX error counter */ | |
43 | ||
44 | /* Messages from the PC to the CPC interface */ | |
45 | #define CPC_CMD_TYPE_CAN_FRAME 1 /* CAN data frame */ | |
46 | #define CPC_CMD_TYPE_CONTROL 3 /* control of interface behavior */ | |
47 | #define CPC_CMD_TYPE_CAN_PARAMS 6 /* set CAN parameters */ | |
48 | #define CPC_CMD_TYPE_RTR_FRAME 13 /* CAN remote frame */ | |
49 | #define CPC_CMD_TYPE_CAN_STATE 14 /* CAN state message */ | |
50 | #define CPC_CMD_TYPE_EXT_CAN_FRAME 15 /* Extended CAN data frame */ | |
51 | #define CPC_CMD_TYPE_EXT_RTR_FRAME 16 /* Extended CAN remote frame */ | |
52 | #define CPC_CMD_TYPE_CAN_EXIT 200 /* exit the CAN */ | |
53 | ||
54 | #define CPC_CMD_TYPE_INQ_ERR_COUNTER 25 /* request the CAN error counters */ | |
55 | #define CPC_CMD_TYPE_CLEAR_MSG_QUEUE 8 /* clear CPC_MSG queue */ | |
56 | #define CPC_CMD_TYPE_CLEAR_CMD_QUEUE 28 /* clear CPC_CMD queue */ | |
57 | ||
58 | #define CPC_CC_TYPE_SJA1000 2 /* Philips basic CAN controller */ | |
59 | ||
60 | #define CPC_CAN_ECODE_ERRFRAME 0x01 /* Ecode type */ | |
61 | ||
62 | /* Overrun types */ | |
63 | #define CPC_OVR_EVENT_CAN 0x01 | |
64 | #define CPC_OVR_EVENT_CANSTATE 0x02 | |
65 | #define CPC_OVR_EVENT_BUSERROR 0x04 | |
66 | ||
67 | /* | |
68 | * If the CAN controller lost a message we indicate it with the highest bit | |
69 | * set in the count field. | |
70 | */ | |
71 | #define CPC_OVR_HW 0x80 | |
72 | ||
73 | /* Size of the "struct ems_cpc_msg" without the union */ | |
74 | #define CPC_MSG_HEADER_LEN 11 | |
75 | #define CPC_CAN_MSG_MIN_SIZE 5 | |
76 | ||
77 | /* Define these values to match your devices */ | |
78 | #define USB_CPCUSB_VENDOR_ID 0x12D6 | |
79 | ||
80 | #define USB_CPCUSB_ARM7_PRODUCT_ID 0x0444 | |
81 | ||
82 | /* Mode register NXP LPC2119/SJA1000 CAN Controller */ | |
83 | #define SJA1000_MOD_NORMAL 0x00 | |
84 | #define SJA1000_MOD_RM 0x01 | |
85 | ||
86 | /* ECC register NXP LPC2119/SJA1000 CAN Controller */ | |
87 | #define SJA1000_ECC_SEG 0x1F | |
88 | #define SJA1000_ECC_DIR 0x20 | |
89 | #define SJA1000_ECC_ERR 0x06 | |
90 | #define SJA1000_ECC_BIT 0x00 | |
91 | #define SJA1000_ECC_FORM 0x40 | |
92 | #define SJA1000_ECC_STUFF 0x80 | |
93 | #define SJA1000_ECC_MASK 0xc0 | |
94 | ||
95 | /* Status register content */ | |
96 | #define SJA1000_SR_BS 0x80 | |
97 | #define SJA1000_SR_ES 0x40 | |
98 | ||
99 | #define SJA1000_DEFAULT_OUTPUT_CONTROL 0xDA | |
100 | ||
101 | /* | |
102 | * The device actually uses a 16MHz clock to generate the CAN clock | |
103 | * but it expects SJA1000 bit settings based on 8MHz (is internally | |
104 | * converted). | |
105 | */ | |
106 | #define EMS_USB_ARM7_CLOCK 8000000 | |
107 | ||
108 | #define CPC_TX_QUEUE_TRIGGER_LOW 25 | |
109 | #define CPC_TX_QUEUE_TRIGGER_HIGH 35 | |
110 | ||
111 | /* | |
112 | * CAN-Message representation in a CPC_MSG. Message object type is | |
113 | * CPC_MSG_TYPE_CAN_FRAME or CPC_MSG_TYPE_RTR_FRAME or | |
114 | * CPC_MSG_TYPE_EXT_CAN_FRAME or CPC_MSG_TYPE_EXT_RTR_FRAME. | |
115 | */ | |
116 | struct cpc_can_msg { | |
117 | __le32 id; | |
118 | u8 length; | |
119 | u8 msg[8]; | |
120 | }; | |
121 | ||
122 | /* Representation of the CAN parameters for the SJA1000 controller */ | |
123 | struct cpc_sja1000_params { | |
124 | u8 mode; | |
125 | u8 acc_code0; | |
126 | u8 acc_code1; | |
127 | u8 acc_code2; | |
128 | u8 acc_code3; | |
129 | u8 acc_mask0; | |
130 | u8 acc_mask1; | |
131 | u8 acc_mask2; | |
132 | u8 acc_mask3; | |
133 | u8 btr0; | |
134 | u8 btr1; | |
135 | u8 outp_contr; | |
136 | }; | |
137 | ||
138 | /* CAN params message representation */ | |
139 | struct cpc_can_params { | |
140 | u8 cc_type; | |
141 | ||
142 | /* Will support M16C CAN controller in the future */ | |
143 | union { | |
144 | struct cpc_sja1000_params sja1000; | |
145 | } cc_params; | |
146 | }; | |
147 | ||
148 | /* Structure for confirmed message handling */ | |
149 | struct cpc_confirm { | |
150 | u8 error; /* error code */ | |
151 | }; | |
152 | ||
153 | /* Structure for overrun conditions */ | |
154 | struct cpc_overrun { | |
155 | u8 event; | |
156 | u8 count; | |
157 | }; | |
158 | ||
159 | /* SJA1000 CAN errors (compatible to NXP LPC2119) */ | |
160 | struct cpc_sja1000_can_error { | |
161 | u8 ecc; | |
162 | u8 rxerr; | |
163 | u8 txerr; | |
164 | }; | |
165 | ||
166 | /* structure for CAN error conditions */ | |
167 | struct cpc_can_error { | |
168 | u8 ecode; | |
169 | ||
170 | struct { | |
171 | u8 cc_type; | |
172 | ||
173 | /* Other controllers may also provide error code capture regs */ | |
174 | union { | |
175 | struct cpc_sja1000_can_error sja1000; | |
176 | } regs; | |
177 | } cc; | |
178 | }; | |
179 | ||
180 | /* | |
181 | * Structure containing RX/TX error counter. This structure is used to request | |
182 | * the values of the CAN controllers TX and RX error counter. | |
183 | */ | |
184 | struct cpc_can_err_counter { | |
185 | u8 rx; | |
186 | u8 tx; | |
187 | }; | |
188 | ||
189 | /* Main message type used between library and application */ | |
190 | struct __packed ems_cpc_msg { | |
191 | u8 type; /* type of message */ | |
192 | u8 length; /* length of data within union 'msg' */ | |
193 | u8 msgid; /* confirmation handle */ | |
194 | __le32 ts_sec; /* timestamp in seconds */ | |
195 | __le32 ts_nsec; /* timestamp in nano seconds */ | |
196 | ||
197 | union { | |
198 | u8 generic[64]; | |
199 | struct cpc_can_msg can_msg; | |
200 | struct cpc_can_params can_params; | |
201 | struct cpc_confirm confirmation; | |
202 | struct cpc_overrun overrun; | |
203 | struct cpc_can_error error; | |
204 | struct cpc_can_err_counter err_counter; | |
205 | u8 can_state; | |
206 | } msg; | |
207 | }; | |
208 | ||
209 | /* | |
210 | * Table of devices that work with this driver | |
211 | * NOTE: This driver supports only CPC-USB/ARM7 (LPC2119) yet. | |
212 | */ | |
213 | static struct usb_device_id ems_usb_table[] = { | |
214 | {USB_DEVICE(USB_CPCUSB_VENDOR_ID, USB_CPCUSB_ARM7_PRODUCT_ID)}, | |
215 | {} /* Terminating entry */ | |
216 | }; | |
217 | ||
218 | MODULE_DEVICE_TABLE(usb, ems_usb_table); | |
219 | ||
220 | #define RX_BUFFER_SIZE 64 | |
221 | #define CPC_HEADER_SIZE 4 | |
222 | #define INTR_IN_BUFFER_SIZE 4 | |
223 | ||
224 | #define MAX_RX_URBS 10 | |
225 | #define MAX_TX_URBS 10 | |
226 | ||
227 | struct ems_usb; | |
228 | ||
229 | struct ems_tx_urb_context { | |
230 | struct ems_usb *dev; | |
231 | ||
232 | u32 echo_index; | |
233 | u8 dlc; | |
234 | }; | |
235 | ||
236 | struct ems_usb { | |
237 | struct can_priv can; /* must be the first member */ | |
238 | ||
239 | struct sk_buff *echo_skb[MAX_TX_URBS]; | |
240 | ||
241 | struct usb_device *udev; | |
242 | struct net_device *netdev; | |
243 | ||
244 | atomic_t active_tx_urbs; | |
245 | struct usb_anchor tx_submitted; | |
246 | struct ems_tx_urb_context tx_contexts[MAX_TX_URBS]; | |
247 | ||
248 | struct usb_anchor rx_submitted; | |
249 | ||
250 | struct urb *intr_urb; | |
251 | ||
252 | u8 *tx_msg_buffer; | |
253 | ||
254 | u8 *intr_in_buffer; | |
255 | unsigned int free_slots; /* remember number of available slots */ | |
256 | ||
257 | struct ems_cpc_msg active_params; /* active controller parameters */ | |
258 | void *rxbuf[MAX_RX_URBS]; | |
259 | dma_addr_t rxbuf_dma[MAX_RX_URBS]; | |
260 | }; | |
261 | ||
262 | static void ems_usb_read_interrupt_callback(struct urb *urb) | |
263 | { | |
264 | struct ems_usb *dev = urb->context; | |
265 | struct net_device *netdev = dev->netdev; | |
266 | int err; | |
267 | ||
268 | if (!netif_device_present(netdev)) | |
269 | return; | |
270 | ||
271 | switch (urb->status) { | |
272 | case 0: | |
273 | dev->free_slots = dev->intr_in_buffer[1]; | |
274 | if (dev->free_slots > CPC_TX_QUEUE_TRIGGER_HIGH && | |
275 | netif_queue_stopped(netdev)) | |
276 | netif_wake_queue(netdev); | |
277 | break; | |
278 | ||
279 | case -ECONNRESET: /* unlink */ | |
280 | case -ENOENT: | |
281 | case -EPIPE: | |
282 | case -EPROTO: | |
283 | case -ESHUTDOWN: | |
284 | return; | |
285 | ||
286 | default: | |
287 | netdev_info(netdev, "Rx interrupt aborted %d\n", urb->status); | |
288 | break; | |
289 | } | |
290 | ||
291 | err = usb_submit_urb(urb, GFP_ATOMIC); | |
292 | ||
293 | if (err == -ENODEV) | |
294 | netif_device_detach(netdev); | |
295 | else if (err) | |
296 | netdev_err(netdev, "failed resubmitting intr urb: %d\n", err); | |
297 | } | |
298 | ||
299 | static void ems_usb_rx_can_msg(struct ems_usb *dev, struct ems_cpc_msg *msg) | |
300 | { | |
301 | struct can_frame *cf; | |
302 | struct sk_buff *skb; | |
303 | int i; | |
304 | struct net_device_stats *stats = &dev->netdev->stats; | |
305 | ||
306 | skb = alloc_can_skb(dev->netdev, &cf); | |
307 | if (skb == NULL) | |
308 | return; | |
309 | ||
310 | cf->can_id = le32_to_cpu(msg->msg.can_msg.id); | |
311 | cf->len = can_cc_dlc2len(msg->msg.can_msg.length & 0xF); | |
312 | ||
313 | if (msg->type == CPC_MSG_TYPE_EXT_CAN_FRAME || | |
314 | msg->type == CPC_MSG_TYPE_EXT_RTR_FRAME) | |
315 | cf->can_id |= CAN_EFF_FLAG; | |
316 | ||
317 | if (msg->type == CPC_MSG_TYPE_RTR_FRAME || | |
318 | msg->type == CPC_MSG_TYPE_EXT_RTR_FRAME) { | |
319 | cf->can_id |= CAN_RTR_FLAG; | |
320 | } else { | |
321 | for (i = 0; i < cf->len; i++) | |
322 | cf->data[i] = msg->msg.can_msg.msg[i]; | |
323 | } | |
324 | ||
325 | stats->rx_packets++; | |
326 | stats->rx_bytes += cf->len; | |
327 | netif_rx(skb); | |
328 | } | |
329 | ||
330 | static void ems_usb_rx_err(struct ems_usb *dev, struct ems_cpc_msg *msg) | |
331 | { | |
332 | struct can_frame *cf; | |
333 | struct sk_buff *skb; | |
334 | struct net_device_stats *stats = &dev->netdev->stats; | |
335 | ||
336 | skb = alloc_can_err_skb(dev->netdev, &cf); | |
337 | if (skb == NULL) | |
338 | return; | |
339 | ||
340 | if (msg->type == CPC_MSG_TYPE_CAN_STATE) { | |
341 | u8 state = msg->msg.can_state; | |
342 | ||
343 | if (state & SJA1000_SR_BS) { | |
344 | dev->can.state = CAN_STATE_BUS_OFF; | |
345 | cf->can_id |= CAN_ERR_BUSOFF; | |
346 | ||
347 | dev->can.can_stats.bus_off++; | |
348 | can_bus_off(dev->netdev); | |
349 | } else if (state & SJA1000_SR_ES) { | |
350 | dev->can.state = CAN_STATE_ERROR_WARNING; | |
351 | dev->can.can_stats.error_warning++; | |
352 | } else { | |
353 | dev->can.state = CAN_STATE_ERROR_ACTIVE; | |
354 | dev->can.can_stats.error_passive++; | |
355 | } | |
356 | } else if (msg->type == CPC_MSG_TYPE_CAN_FRAME_ERROR) { | |
357 | u8 ecc = msg->msg.error.cc.regs.sja1000.ecc; | |
358 | u8 txerr = msg->msg.error.cc.regs.sja1000.txerr; | |
359 | u8 rxerr = msg->msg.error.cc.regs.sja1000.rxerr; | |
360 | ||
361 | /* bus error interrupt */ | |
362 | dev->can.can_stats.bus_error++; | |
363 | stats->rx_errors++; | |
364 | ||
365 | cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR; | |
366 | ||
367 | switch (ecc & SJA1000_ECC_MASK) { | |
368 | case SJA1000_ECC_BIT: | |
369 | cf->data[2] |= CAN_ERR_PROT_BIT; | |
370 | break; | |
371 | case SJA1000_ECC_FORM: | |
372 | cf->data[2] |= CAN_ERR_PROT_FORM; | |
373 | break; | |
374 | case SJA1000_ECC_STUFF: | |
375 | cf->data[2] |= CAN_ERR_PROT_STUFF; | |
376 | break; | |
377 | default: | |
378 | cf->data[3] = ecc & SJA1000_ECC_SEG; | |
379 | break; | |
380 | } | |
381 | ||
382 | /* Error occurred during transmission? */ | |
383 | if ((ecc & SJA1000_ECC_DIR) == 0) | |
384 | cf->data[2] |= CAN_ERR_PROT_TX; | |
385 | ||
386 | if (dev->can.state == CAN_STATE_ERROR_WARNING || | |
387 | dev->can.state == CAN_STATE_ERROR_PASSIVE) { | |
388 | cf->can_id |= CAN_ERR_CRTL; | |
389 | cf->data[1] = (txerr > rxerr) ? | |
390 | CAN_ERR_CRTL_TX_PASSIVE : CAN_ERR_CRTL_RX_PASSIVE; | |
391 | } | |
392 | } else if (msg->type == CPC_MSG_TYPE_OVERRUN) { | |
393 | cf->can_id |= CAN_ERR_CRTL; | |
394 | cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW; | |
395 | ||
396 | stats->rx_over_errors++; | |
397 | stats->rx_errors++; | |
398 | } | |
399 | ||
400 | stats->rx_packets++; | |
401 | stats->rx_bytes += cf->len; | |
402 | netif_rx(skb); | |
403 | } | |
404 | ||
405 | /* | |
406 | * callback for bulk IN urb | |
407 | */ | |
408 | static void ems_usb_read_bulk_callback(struct urb *urb) | |
409 | { | |
410 | struct ems_usb *dev = urb->context; | |
411 | struct net_device *netdev; | |
412 | int retval; | |
413 | ||
414 | netdev = dev->netdev; | |
415 | ||
416 | if (!netif_device_present(netdev)) | |
417 | return; | |
418 | ||
419 | switch (urb->status) { | |
420 | case 0: /* success */ | |
421 | break; | |
422 | ||
423 | case -ENOENT: | |
424 | return; | |
425 | ||
426 | default: | |
427 | netdev_info(netdev, "Rx URB aborted (%d)\n", urb->status); | |
428 | goto resubmit_urb; | |
429 | } | |
430 | ||
431 | if (urb->actual_length > CPC_HEADER_SIZE) { | |
432 | struct ems_cpc_msg *msg; | |
433 | u8 *ibuf = urb->transfer_buffer; | |
434 | u8 msg_count, start; | |
435 | ||
436 | msg_count = ibuf[0] & ~0x80; | |
437 | ||
438 | start = CPC_HEADER_SIZE; | |
439 | ||
440 | while (msg_count) { | |
441 | msg = (struct ems_cpc_msg *)&ibuf[start]; | |
442 | ||
443 | switch (msg->type) { | |
444 | case CPC_MSG_TYPE_CAN_STATE: | |
445 | /* Process CAN state changes */ | |
446 | ems_usb_rx_err(dev, msg); | |
447 | break; | |
448 | ||
449 | case CPC_MSG_TYPE_CAN_FRAME: | |
450 | case CPC_MSG_TYPE_EXT_CAN_FRAME: | |
451 | case CPC_MSG_TYPE_RTR_FRAME: | |
452 | case CPC_MSG_TYPE_EXT_RTR_FRAME: | |
453 | ems_usb_rx_can_msg(dev, msg); | |
454 | break; | |
455 | ||
456 | case CPC_MSG_TYPE_CAN_FRAME_ERROR: | |
457 | /* Process errorframe */ | |
458 | ems_usb_rx_err(dev, msg); | |
459 | break; | |
460 | ||
461 | case CPC_MSG_TYPE_OVERRUN: | |
462 | /* Message lost while receiving */ | |
463 | ems_usb_rx_err(dev, msg); | |
464 | break; | |
465 | } | |
466 | ||
467 | start += CPC_MSG_HEADER_LEN + msg->length; | |
468 | msg_count--; | |
469 | ||
470 | if (start > urb->transfer_buffer_length) { | |
471 | netdev_err(netdev, "format error\n"); | |
472 | break; | |
473 | } | |
474 | } | |
475 | } | |
476 | ||
477 | resubmit_urb: | |
478 | usb_fill_bulk_urb(urb, dev->udev, usb_rcvbulkpipe(dev->udev, 2), | |
479 | urb->transfer_buffer, RX_BUFFER_SIZE, | |
480 | ems_usb_read_bulk_callback, dev); | |
481 | ||
482 | retval = usb_submit_urb(urb, GFP_ATOMIC); | |
483 | ||
484 | if (retval == -ENODEV) | |
485 | netif_device_detach(netdev); | |
486 | else if (retval) | |
487 | netdev_err(netdev, | |
488 | "failed resubmitting read bulk urb: %d\n", retval); | |
489 | } | |
490 | ||
491 | /* | |
492 | * callback for bulk IN urb | |
493 | */ | |
494 | static void ems_usb_write_bulk_callback(struct urb *urb) | |
495 | { | |
496 | struct ems_tx_urb_context *context = urb->context; | |
497 | struct ems_usb *dev; | |
498 | struct net_device *netdev; | |
499 | ||
500 | BUG_ON(!context); | |
501 | ||
502 | dev = context->dev; | |
503 | netdev = dev->netdev; | |
504 | ||
505 | /* free up our allocated buffer */ | |
506 | usb_free_coherent(urb->dev, urb->transfer_buffer_length, | |
507 | urb->transfer_buffer, urb->transfer_dma); | |
508 | ||
509 | atomic_dec(&dev->active_tx_urbs); | |
510 | ||
511 | if (!netif_device_present(netdev)) | |
512 | return; | |
513 | ||
514 | if (urb->status) | |
515 | netdev_info(netdev, "Tx URB aborted (%d)\n", urb->status); | |
516 | ||
517 | netif_trans_update(netdev); | |
518 | ||
519 | /* transmission complete interrupt */ | |
520 | netdev->stats.tx_packets++; | |
521 | netdev->stats.tx_bytes += context->dlc; | |
522 | ||
523 | can_get_echo_skb(netdev, context->echo_index, NULL); | |
524 | ||
525 | /* Release context */ | |
526 | context->echo_index = MAX_TX_URBS; | |
527 | ||
528 | } | |
529 | ||
530 | /* | |
531 | * Send the given CPC command synchronously | |
532 | */ | |
533 | static int ems_usb_command_msg(struct ems_usb *dev, struct ems_cpc_msg *msg) | |
534 | { | |
535 | int actual_length; | |
536 | ||
537 | /* Copy payload */ | |
538 | memcpy(&dev->tx_msg_buffer[CPC_HEADER_SIZE], msg, | |
539 | msg->length + CPC_MSG_HEADER_LEN); | |
540 | ||
541 | /* Clear header */ | |
542 | memset(&dev->tx_msg_buffer[0], 0, CPC_HEADER_SIZE); | |
543 | ||
544 | return usb_bulk_msg(dev->udev, usb_sndbulkpipe(dev->udev, 2), | |
545 | &dev->tx_msg_buffer[0], | |
546 | msg->length + CPC_MSG_HEADER_LEN + CPC_HEADER_SIZE, | |
547 | &actual_length, 1000); | |
548 | } | |
549 | ||
550 | /* | |
551 | * Change CAN controllers' mode register | |
552 | */ | |
553 | static int ems_usb_write_mode(struct ems_usb *dev, u8 mode) | |
554 | { | |
555 | dev->active_params.msg.can_params.cc_params.sja1000.mode = mode; | |
556 | ||
557 | return ems_usb_command_msg(dev, &dev->active_params); | |
558 | } | |
559 | ||
560 | /* | |
561 | * Send a CPC_Control command to change behaviour when interface receives a CAN | |
562 | * message, bus error or CAN state changed notifications. | |
563 | */ | |
564 | static int ems_usb_control_cmd(struct ems_usb *dev, u8 val) | |
565 | { | |
566 | struct ems_cpc_msg cmd; | |
567 | ||
568 | cmd.type = CPC_CMD_TYPE_CONTROL; | |
569 | cmd.length = CPC_MSG_HEADER_LEN + 1; | |
570 | ||
571 | cmd.msgid = 0; | |
572 | ||
573 | cmd.msg.generic[0] = val; | |
574 | ||
575 | return ems_usb_command_msg(dev, &cmd); | |
576 | } | |
577 | ||
578 | /* | |
579 | * Start interface | |
580 | */ | |
581 | static int ems_usb_start(struct ems_usb *dev) | |
582 | { | |
583 | struct net_device *netdev = dev->netdev; | |
584 | int err, i; | |
585 | ||
586 | dev->intr_in_buffer[0] = 0; | |
587 | dev->free_slots = 50; /* initial size */ | |
588 | ||
589 | for (i = 0; i < MAX_RX_URBS; i++) { | |
590 | struct urb *urb = NULL; | |
591 | u8 *buf = NULL; | |
592 | dma_addr_t buf_dma; | |
593 | ||
594 | /* create a URB, and a buffer for it */ | |
595 | urb = usb_alloc_urb(0, GFP_KERNEL); | |
596 | if (!urb) { | |
597 | err = -ENOMEM; | |
598 | break; | |
599 | } | |
600 | ||
601 | buf = usb_alloc_coherent(dev->udev, RX_BUFFER_SIZE, GFP_KERNEL, | |
602 | &buf_dma); | |
603 | if (!buf) { | |
604 | netdev_err(netdev, "No memory left for USB buffer\n"); | |
605 | usb_free_urb(urb); | |
606 | err = -ENOMEM; | |
607 | break; | |
608 | } | |
609 | ||
610 | urb->transfer_dma = buf_dma; | |
611 | ||
612 | usb_fill_bulk_urb(urb, dev->udev, usb_rcvbulkpipe(dev->udev, 2), | |
613 | buf, RX_BUFFER_SIZE, | |
614 | ems_usb_read_bulk_callback, dev); | |
615 | urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; | |
616 | usb_anchor_urb(urb, &dev->rx_submitted); | |
617 | ||
618 | err = usb_submit_urb(urb, GFP_KERNEL); | |
619 | if (err) { | |
620 | usb_unanchor_urb(urb); | |
621 | usb_free_coherent(dev->udev, RX_BUFFER_SIZE, buf, | |
622 | urb->transfer_dma); | |
623 | usb_free_urb(urb); | |
624 | break; | |
625 | } | |
626 | ||
627 | dev->rxbuf[i] = buf; | |
628 | dev->rxbuf_dma[i] = buf_dma; | |
629 | ||
630 | /* Drop reference, USB core will take care of freeing it */ | |
631 | usb_free_urb(urb); | |
632 | } | |
633 | ||
634 | /* Did we submit any URBs */ | |
635 | if (i == 0) { | |
636 | netdev_warn(netdev, "couldn't setup read URBs\n"); | |
637 | return err; | |
638 | } | |
639 | ||
640 | /* Warn if we've couldn't transmit all the URBs */ | |
641 | if (i < MAX_RX_URBS) | |
642 | netdev_warn(netdev, "rx performance may be slow\n"); | |
643 | ||
644 | /* Setup and start interrupt URB */ | |
645 | usb_fill_int_urb(dev->intr_urb, dev->udev, | |
646 | usb_rcvintpipe(dev->udev, 1), | |
647 | dev->intr_in_buffer, | |
648 | INTR_IN_BUFFER_SIZE, | |
649 | ems_usb_read_interrupt_callback, dev, 1); | |
650 | ||
651 | err = usb_submit_urb(dev->intr_urb, GFP_KERNEL); | |
652 | if (err) { | |
653 | netdev_warn(netdev, "intr URB submit failed: %d\n", err); | |
654 | ||
655 | return err; | |
656 | } | |
657 | ||
658 | /* CPC-USB will transfer received message to host */ | |
659 | err = ems_usb_control_cmd(dev, CONTR_CAN_MESSAGE | CONTR_CONT_ON); | |
660 | if (err) | |
661 | goto failed; | |
662 | ||
663 | /* CPC-USB will transfer CAN state changes to host */ | |
664 | err = ems_usb_control_cmd(dev, CONTR_CAN_STATE | CONTR_CONT_ON); | |
665 | if (err) | |
666 | goto failed; | |
667 | ||
668 | /* CPC-USB will transfer bus errors to host */ | |
669 | err = ems_usb_control_cmd(dev, CONTR_BUS_ERROR | CONTR_CONT_ON); | |
670 | if (err) | |
671 | goto failed; | |
672 | ||
673 | err = ems_usb_write_mode(dev, SJA1000_MOD_NORMAL); | |
674 | if (err) | |
675 | goto failed; | |
676 | ||
677 | dev->can.state = CAN_STATE_ERROR_ACTIVE; | |
678 | ||
679 | return 0; | |
680 | ||
681 | failed: | |
682 | netdev_warn(netdev, "couldn't submit control: %d\n", err); | |
683 | ||
684 | return err; | |
685 | } | |
686 | ||
687 | static void unlink_all_urbs(struct ems_usb *dev) | |
688 | { | |
689 | int i; | |
690 | ||
691 | usb_unlink_urb(dev->intr_urb); | |
692 | ||
693 | usb_kill_anchored_urbs(&dev->rx_submitted); | |
694 | ||
695 | for (i = 0; i < MAX_RX_URBS; ++i) | |
696 | usb_free_coherent(dev->udev, RX_BUFFER_SIZE, | |
697 | dev->rxbuf[i], dev->rxbuf_dma[i]); | |
698 | ||
699 | usb_kill_anchored_urbs(&dev->tx_submitted); | |
700 | atomic_set(&dev->active_tx_urbs, 0); | |
701 | ||
702 | for (i = 0; i < MAX_TX_URBS; i++) | |
703 | dev->tx_contexts[i].echo_index = MAX_TX_URBS; | |
704 | } | |
705 | ||
706 | static int ems_usb_open(struct net_device *netdev) | |
707 | { | |
708 | struct ems_usb *dev = netdev_priv(netdev); | |
709 | int err; | |
710 | ||
711 | err = ems_usb_write_mode(dev, SJA1000_MOD_RM); | |
712 | if (err) | |
713 | return err; | |
714 | ||
715 | /* common open */ | |
716 | err = open_candev(netdev); | |
717 | if (err) | |
718 | return err; | |
719 | ||
720 | /* finally start device */ | |
721 | err = ems_usb_start(dev); | |
722 | if (err) { | |
723 | if (err == -ENODEV) | |
724 | netif_device_detach(dev->netdev); | |
725 | ||
726 | netdev_warn(netdev, "couldn't start device: %d\n", err); | |
727 | ||
728 | close_candev(netdev); | |
729 | ||
730 | return err; | |
731 | } | |
732 | ||
733 | ||
734 | netif_start_queue(netdev); | |
735 | ||
736 | return 0; | |
737 | } | |
738 | ||
739 | static netdev_tx_t ems_usb_start_xmit(struct sk_buff *skb, struct net_device *netdev) | |
740 | { | |
741 | struct ems_usb *dev = netdev_priv(netdev); | |
742 | struct ems_tx_urb_context *context = NULL; | |
743 | struct net_device_stats *stats = &netdev->stats; | |
744 | struct can_frame *cf = (struct can_frame *)skb->data; | |
745 | struct ems_cpc_msg *msg; | |
746 | struct urb *urb; | |
747 | u8 *buf; | |
748 | int i, err; | |
749 | size_t size = CPC_HEADER_SIZE + CPC_MSG_HEADER_LEN | |
750 | + sizeof(struct cpc_can_msg); | |
751 | ||
752 | if (can_dropped_invalid_skb(netdev, skb)) | |
753 | return NETDEV_TX_OK; | |
754 | ||
755 | /* create a URB, and a buffer for it, and copy the data to the URB */ | |
756 | urb = usb_alloc_urb(0, GFP_ATOMIC); | |
757 | if (!urb) | |
758 | goto nomem; | |
759 | ||
760 | buf = usb_alloc_coherent(dev->udev, size, GFP_ATOMIC, &urb->transfer_dma); | |
761 | if (!buf) { | |
762 | netdev_err(netdev, "No memory left for USB buffer\n"); | |
763 | usb_free_urb(urb); | |
764 | goto nomem; | |
765 | } | |
766 | ||
767 | msg = (struct ems_cpc_msg *)&buf[CPC_HEADER_SIZE]; | |
768 | ||
769 | msg->msg.can_msg.id = cpu_to_le32(cf->can_id & CAN_ERR_MASK); | |
770 | msg->msg.can_msg.length = cf->len; | |
771 | ||
772 | if (cf->can_id & CAN_RTR_FLAG) { | |
773 | msg->type = cf->can_id & CAN_EFF_FLAG ? | |
774 | CPC_CMD_TYPE_EXT_RTR_FRAME : CPC_CMD_TYPE_RTR_FRAME; | |
775 | ||
776 | msg->length = CPC_CAN_MSG_MIN_SIZE; | |
777 | } else { | |
778 | msg->type = cf->can_id & CAN_EFF_FLAG ? | |
779 | CPC_CMD_TYPE_EXT_CAN_FRAME : CPC_CMD_TYPE_CAN_FRAME; | |
780 | ||
781 | for (i = 0; i < cf->len; i++) | |
782 | msg->msg.can_msg.msg[i] = cf->data[i]; | |
783 | ||
784 | msg->length = CPC_CAN_MSG_MIN_SIZE + cf->len; | |
785 | } | |
786 | ||
787 | for (i = 0; i < MAX_TX_URBS; i++) { | |
788 | if (dev->tx_contexts[i].echo_index == MAX_TX_URBS) { | |
789 | context = &dev->tx_contexts[i]; | |
790 | break; | |
791 | } | |
792 | } | |
793 | ||
794 | /* | |
795 | * May never happen! When this happens we'd more URBs in flight as | |
796 | * allowed (MAX_TX_URBS). | |
797 | */ | |
798 | if (!context) { | |
799 | usb_free_coherent(dev->udev, size, buf, urb->transfer_dma); | |
800 | usb_free_urb(urb); | |
801 | ||
802 | netdev_warn(netdev, "couldn't find free context\n"); | |
803 | ||
804 | return NETDEV_TX_BUSY; | |
805 | } | |
806 | ||
807 | context->dev = dev; | |
808 | context->echo_index = i; | |
809 | context->dlc = cf->len; | |
810 | ||
811 | usb_fill_bulk_urb(urb, dev->udev, usb_sndbulkpipe(dev->udev, 2), buf, | |
812 | size, ems_usb_write_bulk_callback, context); | |
813 | urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; | |
814 | usb_anchor_urb(urb, &dev->tx_submitted); | |
815 | ||
816 | can_put_echo_skb(skb, netdev, context->echo_index, 0); | |
817 | ||
818 | atomic_inc(&dev->active_tx_urbs); | |
819 | ||
820 | err = usb_submit_urb(urb, GFP_ATOMIC); | |
821 | if (unlikely(err)) { | |
822 | can_free_echo_skb(netdev, context->echo_index, NULL); | |
823 | ||
824 | usb_unanchor_urb(urb); | |
825 | usb_free_coherent(dev->udev, size, buf, urb->transfer_dma); | |
826 | ||
827 | atomic_dec(&dev->active_tx_urbs); | |
828 | ||
829 | if (err == -ENODEV) { | |
830 | netif_device_detach(netdev); | |
831 | } else { | |
832 | netdev_warn(netdev, "failed tx_urb %d\n", err); | |
833 | ||
834 | stats->tx_dropped++; | |
835 | } | |
836 | } else { | |
837 | netif_trans_update(netdev); | |
838 | ||
839 | /* Slow down tx path */ | |
840 | if (atomic_read(&dev->active_tx_urbs) >= MAX_TX_URBS || | |
841 | dev->free_slots < CPC_TX_QUEUE_TRIGGER_LOW) { | |
842 | netif_stop_queue(netdev); | |
843 | } | |
844 | } | |
845 | ||
846 | /* | |
847 | * Release our reference to this URB, the USB core will eventually free | |
848 | * it entirely. | |
849 | */ | |
850 | usb_free_urb(urb); | |
851 | ||
852 | return NETDEV_TX_OK; | |
853 | ||
854 | nomem: | |
855 | dev_kfree_skb(skb); | |
856 | stats->tx_dropped++; | |
857 | ||
858 | return NETDEV_TX_OK; | |
859 | } | |
860 | ||
861 | static int ems_usb_close(struct net_device *netdev) | |
862 | { | |
863 | struct ems_usb *dev = netdev_priv(netdev); | |
864 | ||
865 | /* Stop polling */ | |
866 | unlink_all_urbs(dev); | |
867 | ||
868 | netif_stop_queue(netdev); | |
869 | ||
870 | /* Set CAN controller to reset mode */ | |
871 | if (ems_usb_write_mode(dev, SJA1000_MOD_RM)) | |
872 | netdev_warn(netdev, "couldn't stop device"); | |
873 | ||
874 | close_candev(netdev); | |
875 | ||
876 | return 0; | |
877 | } | |
878 | ||
879 | static const struct net_device_ops ems_usb_netdev_ops = { | |
880 | .ndo_open = ems_usb_open, | |
881 | .ndo_stop = ems_usb_close, | |
882 | .ndo_start_xmit = ems_usb_start_xmit, | |
883 | .ndo_change_mtu = can_change_mtu, | |
884 | }; | |
885 | ||
886 | static const struct can_bittiming_const ems_usb_bittiming_const = { | |
887 | .name = "ems_usb", | |
888 | .tseg1_min = 1, | |
889 | .tseg1_max = 16, | |
890 | .tseg2_min = 1, | |
891 | .tseg2_max = 8, | |
892 | .sjw_max = 4, | |
893 | .brp_min = 1, | |
894 | .brp_max = 64, | |
895 | .brp_inc = 1, | |
896 | }; | |
897 | ||
898 | static int ems_usb_set_mode(struct net_device *netdev, enum can_mode mode) | |
899 | { | |
900 | struct ems_usb *dev = netdev_priv(netdev); | |
901 | ||
902 | switch (mode) { | |
903 | case CAN_MODE_START: | |
904 | if (ems_usb_write_mode(dev, SJA1000_MOD_NORMAL)) | |
905 | netdev_warn(netdev, "couldn't start device"); | |
906 | ||
907 | if (netif_queue_stopped(netdev)) | |
908 | netif_wake_queue(netdev); | |
909 | break; | |
910 | ||
911 | default: | |
912 | return -EOPNOTSUPP; | |
913 | } | |
914 | ||
915 | return 0; | |
916 | } | |
917 | ||
918 | static int ems_usb_set_bittiming(struct net_device *netdev) | |
919 | { | |
920 | struct ems_usb *dev = netdev_priv(netdev); | |
921 | struct can_bittiming *bt = &dev->can.bittiming; | |
922 | u8 btr0, btr1; | |
923 | ||
924 | btr0 = ((bt->brp - 1) & 0x3f) | (((bt->sjw - 1) & 0x3) << 6); | |
925 | btr1 = ((bt->prop_seg + bt->phase_seg1 - 1) & 0xf) | | |
926 | (((bt->phase_seg2 - 1) & 0x7) << 4); | |
927 | if (dev->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES) | |
928 | btr1 |= 0x80; | |
929 | ||
930 | netdev_info(netdev, "setting BTR0=0x%02x BTR1=0x%02x\n", btr0, btr1); | |
931 | ||
932 | dev->active_params.msg.can_params.cc_params.sja1000.btr0 = btr0; | |
933 | dev->active_params.msg.can_params.cc_params.sja1000.btr1 = btr1; | |
934 | ||
935 | return ems_usb_command_msg(dev, &dev->active_params); | |
936 | } | |
937 | ||
938 | static void init_params_sja1000(struct ems_cpc_msg *msg) | |
939 | { | |
940 | struct cpc_sja1000_params *sja1000 = | |
941 | &msg->msg.can_params.cc_params.sja1000; | |
942 | ||
943 | msg->type = CPC_CMD_TYPE_CAN_PARAMS; | |
944 | msg->length = sizeof(struct cpc_can_params); | |
945 | msg->msgid = 0; | |
946 | ||
947 | msg->msg.can_params.cc_type = CPC_CC_TYPE_SJA1000; | |
948 | ||
949 | /* Acceptance filter open */ | |
950 | sja1000->acc_code0 = 0x00; | |
951 | sja1000->acc_code1 = 0x00; | |
952 | sja1000->acc_code2 = 0x00; | |
953 | sja1000->acc_code3 = 0x00; | |
954 | ||
955 | /* Acceptance filter open */ | |
956 | sja1000->acc_mask0 = 0xFF; | |
957 | sja1000->acc_mask1 = 0xFF; | |
958 | sja1000->acc_mask2 = 0xFF; | |
959 | sja1000->acc_mask3 = 0xFF; | |
960 | ||
961 | sja1000->btr0 = 0; | |
962 | sja1000->btr1 = 0; | |
963 | ||
964 | sja1000->outp_contr = SJA1000_DEFAULT_OUTPUT_CONTROL; | |
965 | sja1000->mode = SJA1000_MOD_RM; | |
966 | } | |
967 | ||
968 | /* | |
969 | * probe function for new CPC-USB devices | |
970 | */ | |
971 | static int ems_usb_probe(struct usb_interface *intf, | |
972 | const struct usb_device_id *id) | |
973 | { | |
974 | struct net_device *netdev; | |
975 | struct ems_usb *dev; | |
976 | int i, err = -ENOMEM; | |
977 | ||
978 | netdev = alloc_candev(sizeof(struct ems_usb), MAX_TX_URBS); | |
979 | if (!netdev) { | |
980 | dev_err(&intf->dev, "ems_usb: Couldn't alloc candev\n"); | |
981 | return -ENOMEM; | |
982 | } | |
983 | ||
984 | dev = netdev_priv(netdev); | |
985 | ||
986 | dev->udev = interface_to_usbdev(intf); | |
987 | dev->netdev = netdev; | |
988 | ||
989 | dev->can.state = CAN_STATE_STOPPED; | |
990 | dev->can.clock.freq = EMS_USB_ARM7_CLOCK; | |
991 | dev->can.bittiming_const = &ems_usb_bittiming_const; | |
992 | dev->can.do_set_bittiming = ems_usb_set_bittiming; | |
993 | dev->can.do_set_mode = ems_usb_set_mode; | |
994 | dev->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES; | |
995 | ||
996 | netdev->netdev_ops = &ems_usb_netdev_ops; | |
997 | ||
998 | netdev->flags |= IFF_ECHO; /* we support local echo */ | |
999 | ||
1000 | init_usb_anchor(&dev->rx_submitted); | |
1001 | ||
1002 | init_usb_anchor(&dev->tx_submitted); | |
1003 | atomic_set(&dev->active_tx_urbs, 0); | |
1004 | ||
1005 | for (i = 0; i < MAX_TX_URBS; i++) | |
1006 | dev->tx_contexts[i].echo_index = MAX_TX_URBS; | |
1007 | ||
1008 | dev->intr_urb = usb_alloc_urb(0, GFP_KERNEL); | |
1009 | if (!dev->intr_urb) | |
1010 | goto cleanup_candev; | |
1011 | ||
1012 | dev->intr_in_buffer = kzalloc(INTR_IN_BUFFER_SIZE, GFP_KERNEL); | |
1013 | if (!dev->intr_in_buffer) | |
1014 | goto cleanup_intr_urb; | |
1015 | ||
1016 | dev->tx_msg_buffer = kzalloc(CPC_HEADER_SIZE + | |
1017 | sizeof(struct ems_cpc_msg), GFP_KERNEL); | |
1018 | if (!dev->tx_msg_buffer) | |
1019 | goto cleanup_intr_in_buffer; | |
1020 | ||
1021 | usb_set_intfdata(intf, dev); | |
1022 | ||
1023 | SET_NETDEV_DEV(netdev, &intf->dev); | |
1024 | ||
1025 | init_params_sja1000(&dev->active_params); | |
1026 | ||
1027 | err = ems_usb_command_msg(dev, &dev->active_params); | |
1028 | if (err) { | |
1029 | netdev_err(netdev, "couldn't initialize controller: %d\n", err); | |
1030 | goto cleanup_tx_msg_buffer; | |
1031 | } | |
1032 | ||
1033 | err = register_candev(netdev); | |
1034 | if (err) { | |
1035 | netdev_err(netdev, "couldn't register CAN device: %d\n", err); | |
1036 | goto cleanup_tx_msg_buffer; | |
1037 | } | |
1038 | ||
1039 | return 0; | |
1040 | ||
1041 | cleanup_tx_msg_buffer: | |
1042 | kfree(dev->tx_msg_buffer); | |
1043 | ||
1044 | cleanup_intr_in_buffer: | |
1045 | kfree(dev->intr_in_buffer); | |
1046 | ||
1047 | cleanup_intr_urb: | |
1048 | usb_free_urb(dev->intr_urb); | |
1049 | ||
1050 | cleanup_candev: | |
1051 | free_candev(netdev); | |
1052 | ||
1053 | return err; | |
1054 | } | |
1055 | ||
1056 | /* | |
1057 | * called by the usb core when the device is removed from the system | |
1058 | */ | |
1059 | static void ems_usb_disconnect(struct usb_interface *intf) | |
1060 | { | |
1061 | struct ems_usb *dev = usb_get_intfdata(intf); | |
1062 | ||
1063 | usb_set_intfdata(intf, NULL); | |
1064 | ||
1065 | if (dev) { | |
1066 | unregister_netdev(dev->netdev); | |
1067 | ||
1068 | unlink_all_urbs(dev); | |
1069 | ||
1070 | usb_free_urb(dev->intr_urb); | |
1071 | ||
1072 | kfree(dev->intr_in_buffer); | |
1073 | kfree(dev->tx_msg_buffer); | |
1074 | ||
1075 | free_candev(dev->netdev); | |
1076 | } | |
1077 | } | |
1078 | ||
1079 | /* usb specific object needed to register this driver with the usb subsystem */ | |
1080 | static struct usb_driver ems_usb_driver = { | |
1081 | .name = "ems_usb", | |
1082 | .probe = ems_usb_probe, | |
1083 | .disconnect = ems_usb_disconnect, | |
1084 | .id_table = ems_usb_table, | |
1085 | }; | |
1086 | ||
1087 | module_usb_driver(ems_usb_driver); |