Commit | Line | Data |
---|---|---|
39549eef WG |
1 | /* |
2 | * Copyright (C) 2005 Marc Kleine-Budde, Pengutronix | |
3 | * Copyright (C) 2006 Andrey Volkov, Varma Electronics | |
4 | * Copyright (C) 2008-2009 Wolfgang Grandegger <wg@grandegger.com> | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify | |
7 | * it under the terms of the version 2 of the GNU General Public License | |
8 | * as published by the Free Software Foundation | |
9 | * | |
10 | * This program is distributed in the hope that it will be useful, | |
11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
13 | * GNU General Public License for more details. | |
14 | * | |
15 | * You should have received a copy of the GNU General Public License | |
16 | * along with this program; if not, write to the Free Software | |
17 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
18 | */ | |
19 | ||
20 | #include <linux/module.h> | |
21 | #include <linux/kernel.h> | |
5a0e3ad6 | 22 | #include <linux/slab.h> |
39549eef WG |
23 | #include <linux/netdevice.h> |
24 | #include <linux/if_arp.h> | |
25 | #include <linux/can.h> | |
26 | #include <linux/can/dev.h> | |
27 | #include <linux/can/netlink.h> | |
28 | #include <net/rtnetlink.h> | |
29 | ||
30 | #define MOD_DESC "CAN device driver interface" | |
31 | ||
32 | MODULE_DESCRIPTION(MOD_DESC); | |
33 | MODULE_LICENSE("GPL v2"); | |
34 | MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>"); | |
35 | ||
36 | #ifdef CONFIG_CAN_CALC_BITTIMING | |
37 | #define CAN_CALC_MAX_ERROR 50 /* in one-tenth of a percent */ | |
38 | ||
39 | /* | |
40 | * Bit-timing calculation derived from: | |
41 | * | |
42 | * Code based on LinCAN sources and H8S2638 project | |
43 | * Copyright 2004-2006 Pavel Pisa - DCE FELK CVUT cz | |
44 | * Copyright 2005 Stanislav Marek | |
45 | * email: pisa@cmp.felk.cvut.cz | |
46 | * | |
47 | * Calculates proper bit-timing parameters for a specified bit-rate | |
48 | * and sample-point, which can then be used to set the bit-timing | |
49 | * registers of the CAN controller. You can find more information | |
50 | * in the header file linux/can/netlink.h. | |
51 | */ | |
52 | static int can_update_spt(const struct can_bittiming_const *btc, | |
53 | int sampl_pt, int tseg, int *tseg1, int *tseg2) | |
54 | { | |
55 | *tseg2 = tseg + 1 - (sampl_pt * (tseg + 1)) / 1000; | |
56 | if (*tseg2 < btc->tseg2_min) | |
57 | *tseg2 = btc->tseg2_min; | |
58 | if (*tseg2 > btc->tseg2_max) | |
59 | *tseg2 = btc->tseg2_max; | |
60 | *tseg1 = tseg - *tseg2; | |
61 | if (*tseg1 > btc->tseg1_max) { | |
62 | *tseg1 = btc->tseg1_max; | |
63 | *tseg2 = tseg - *tseg1; | |
64 | } | |
65 | return 1000 * (tseg + 1 - *tseg2) / (tseg + 1); | |
66 | } | |
67 | ||
68 | static int can_calc_bittiming(struct net_device *dev, struct can_bittiming *bt) | |
69 | { | |
70 | struct can_priv *priv = netdev_priv(dev); | |
71 | const struct can_bittiming_const *btc = priv->bittiming_const; | |
72 | long rate, best_rate = 0; | |
73 | long best_error = 1000000000, error = 0; | |
74 | int best_tseg = 0, best_brp = 0, brp = 0; | |
75 | int tsegall, tseg = 0, tseg1 = 0, tseg2 = 0; | |
76 | int spt_error = 1000, spt = 0, sampl_pt; | |
77 | u64 v64; | |
78 | ||
79 | if (!priv->bittiming_const) | |
80 | return -ENOTSUPP; | |
81 | ||
82 | /* Use CIA recommended sample points */ | |
83 | if (bt->sample_point) { | |
84 | sampl_pt = bt->sample_point; | |
85 | } else { | |
86 | if (bt->bitrate > 800000) | |
87 | sampl_pt = 750; | |
88 | else if (bt->bitrate > 500000) | |
89 | sampl_pt = 800; | |
90 | else | |
91 | sampl_pt = 875; | |
92 | } | |
93 | ||
94 | /* tseg even = round down, odd = round up */ | |
95 | for (tseg = (btc->tseg1_max + btc->tseg2_max) * 2 + 1; | |
96 | tseg >= (btc->tseg1_min + btc->tseg2_min) * 2; tseg--) { | |
97 | tsegall = 1 + tseg / 2; | |
98 | /* Compute all possible tseg choices (tseg=tseg1+tseg2) */ | |
99 | brp = priv->clock.freq / (tsegall * bt->bitrate) + tseg % 2; | |
100 | /* chose brp step which is possible in system */ | |
101 | brp = (brp / btc->brp_inc) * btc->brp_inc; | |
102 | if ((brp < btc->brp_min) || (brp > btc->brp_max)) | |
103 | continue; | |
104 | rate = priv->clock.freq / (brp * tsegall); | |
105 | error = bt->bitrate - rate; | |
106 | /* tseg brp biterror */ | |
107 | if (error < 0) | |
108 | error = -error; | |
109 | if (error > best_error) | |
110 | continue; | |
111 | best_error = error; | |
112 | if (error == 0) { | |
113 | spt = can_update_spt(btc, sampl_pt, tseg / 2, | |
114 | &tseg1, &tseg2); | |
115 | error = sampl_pt - spt; | |
116 | if (error < 0) | |
117 | error = -error; | |
118 | if (error > spt_error) | |
119 | continue; | |
120 | spt_error = error; | |
121 | } | |
122 | best_tseg = tseg / 2; | |
123 | best_brp = brp; | |
124 | best_rate = rate; | |
125 | if (error == 0) | |
126 | break; | |
127 | } | |
128 | ||
129 | if (best_error) { | |
130 | /* Error in one-tenth of a percent */ | |
131 | error = (best_error * 1000) / bt->bitrate; | |
132 | if (error > CAN_CALC_MAX_ERROR) { | |
133 | dev_err(dev->dev.parent, | |
134 | "bitrate error %ld.%ld%% too high\n", | |
135 | error / 10, error % 10); | |
136 | return -EDOM; | |
137 | } else { | |
138 | dev_warn(dev->dev.parent, "bitrate error %ld.%ld%%\n", | |
139 | error / 10, error % 10); | |
140 | } | |
141 | } | |
142 | ||
143 | /* real sample point */ | |
144 | bt->sample_point = can_update_spt(btc, sampl_pt, best_tseg, | |
145 | &tseg1, &tseg2); | |
146 | ||
147 | v64 = (u64)best_brp * 1000000000UL; | |
148 | do_div(v64, priv->clock.freq); | |
149 | bt->tq = (u32)v64; | |
150 | bt->prop_seg = tseg1 / 2; | |
151 | bt->phase_seg1 = tseg1 - bt->prop_seg; | |
152 | bt->phase_seg2 = tseg2; | |
153 | bt->sjw = 1; | |
154 | bt->brp = best_brp; | |
155 | /* real bit-rate */ | |
156 | bt->bitrate = priv->clock.freq / (bt->brp * (tseg1 + tseg2 + 1)); | |
157 | ||
158 | return 0; | |
159 | } | |
160 | #else /* !CONFIG_CAN_CALC_BITTIMING */ | |
161 | static int can_calc_bittiming(struct net_device *dev, struct can_bittiming *bt) | |
162 | { | |
163 | dev_err(dev->dev.parent, "bit-timing calculation not available\n"); | |
164 | return -EINVAL; | |
165 | } | |
166 | #endif /* CONFIG_CAN_CALC_BITTIMING */ | |
167 | ||
168 | /* | |
169 | * Checks the validity of the specified bit-timing parameters prop_seg, | |
170 | * phase_seg1, phase_seg2 and sjw and tries to determine the bitrate | |
171 | * prescaler value brp. You can find more information in the header | |
172 | * file linux/can/netlink.h. | |
173 | */ | |
174 | static int can_fixup_bittiming(struct net_device *dev, struct can_bittiming *bt) | |
175 | { | |
176 | struct can_priv *priv = netdev_priv(dev); | |
177 | const struct can_bittiming_const *btc = priv->bittiming_const; | |
178 | int tseg1, alltseg; | |
179 | u64 brp64; | |
180 | ||
181 | if (!priv->bittiming_const) | |
182 | return -ENOTSUPP; | |
183 | ||
184 | tseg1 = bt->prop_seg + bt->phase_seg1; | |
185 | if (!bt->sjw) | |
186 | bt->sjw = 1; | |
187 | if (bt->sjw > btc->sjw_max || | |
188 | tseg1 < btc->tseg1_min || tseg1 > btc->tseg1_max || | |
189 | bt->phase_seg2 < btc->tseg2_min || bt->phase_seg2 > btc->tseg2_max) | |
190 | return -ERANGE; | |
191 | ||
192 | brp64 = (u64)priv->clock.freq * (u64)bt->tq; | |
193 | if (btc->brp_inc > 1) | |
194 | do_div(brp64, btc->brp_inc); | |
195 | brp64 += 500000000UL - 1; | |
196 | do_div(brp64, 1000000000UL); /* the practicable BRP */ | |
197 | if (btc->brp_inc > 1) | |
198 | brp64 *= btc->brp_inc; | |
199 | bt->brp = (u32)brp64; | |
200 | ||
201 | if (bt->brp < btc->brp_min || bt->brp > btc->brp_max) | |
202 | return -EINVAL; | |
203 | ||
204 | alltseg = bt->prop_seg + bt->phase_seg1 + bt->phase_seg2 + 1; | |
205 | bt->bitrate = priv->clock.freq / (bt->brp * alltseg); | |
206 | bt->sample_point = ((tseg1 + 1) * 1000) / alltseg; | |
207 | ||
208 | return 0; | |
209 | } | |
210 | ||
61463a30 | 211 | static int can_get_bittiming(struct net_device *dev, struct can_bittiming *bt) |
39549eef WG |
212 | { |
213 | struct can_priv *priv = netdev_priv(dev); | |
214 | int err; | |
215 | ||
216 | /* Check if the CAN device has bit-timing parameters */ | |
217 | if (priv->bittiming_const) { | |
218 | ||
219 | /* Non-expert mode? Check if the bitrate has been pre-defined */ | |
220 | if (!bt->tq) | |
221 | /* Determine bit-timing parameters */ | |
222 | err = can_calc_bittiming(dev, bt); | |
223 | else | |
224 | /* Check bit-timing params and calculate proper brp */ | |
225 | err = can_fixup_bittiming(dev, bt); | |
226 | if (err) | |
227 | return err; | |
228 | } | |
229 | ||
230 | return 0; | |
231 | } | |
232 | ||
233 | /* | |
234 | * Local echo of CAN messages | |
235 | * | |
236 | * CAN network devices *should* support a local echo functionality | |
237 | * (see Documentation/networking/can.txt). To test the handling of CAN | |
238 | * interfaces that do not support the local echo both driver types are | |
239 | * implemented. In the case that the driver does not support the echo | |
240 | * the IFF_ECHO remains clear in dev->flags. This causes the PF_CAN core | |
241 | * to perform the echo as a fallback solution. | |
242 | */ | |
243 | static void can_flush_echo_skb(struct net_device *dev) | |
244 | { | |
245 | struct can_priv *priv = netdev_priv(dev); | |
246 | struct net_device_stats *stats = &dev->stats; | |
247 | int i; | |
248 | ||
a6e4bc53 | 249 | for (i = 0; i < priv->echo_skb_max; i++) { |
39549eef WG |
250 | if (priv->echo_skb[i]) { |
251 | kfree_skb(priv->echo_skb[i]); | |
252 | priv->echo_skb[i] = NULL; | |
253 | stats->tx_dropped++; | |
254 | stats->tx_aborted_errors++; | |
255 | } | |
256 | } | |
257 | } | |
258 | ||
259 | /* | |
260 | * Put the skb on the stack to be looped backed locally lateron | |
261 | * | |
262 | * The function is typically called in the start_xmit function | |
263 | * of the device driver. The driver must protect access to | |
264 | * priv->echo_skb, if necessary. | |
265 | */ | |
a6e4bc53 WG |
266 | void can_put_echo_skb(struct sk_buff *skb, struct net_device *dev, |
267 | unsigned int idx) | |
39549eef WG |
268 | { |
269 | struct can_priv *priv = netdev_priv(dev); | |
270 | ||
a6e4bc53 WG |
271 | BUG_ON(idx >= priv->echo_skb_max); |
272 | ||
39549eef WG |
273 | /* check flag whether this packet has to be looped back */ |
274 | if (!(dev->flags & IFF_ECHO) || skb->pkt_type != PACKET_LOOPBACK) { | |
275 | kfree_skb(skb); | |
276 | return; | |
277 | } | |
278 | ||
279 | if (!priv->echo_skb[idx]) { | |
280 | struct sock *srcsk = skb->sk; | |
281 | ||
282 | if (atomic_read(&skb->users) != 1) { | |
283 | struct sk_buff *old_skb = skb; | |
284 | ||
285 | skb = skb_clone(old_skb, GFP_ATOMIC); | |
286 | kfree_skb(old_skb); | |
287 | if (!skb) | |
288 | return; | |
289 | } else | |
290 | skb_orphan(skb); | |
291 | ||
292 | skb->sk = srcsk; | |
293 | ||
294 | /* make settings for echo to reduce code in irq context */ | |
295 | skb->protocol = htons(ETH_P_CAN); | |
296 | skb->pkt_type = PACKET_BROADCAST; | |
297 | skb->ip_summed = CHECKSUM_UNNECESSARY; | |
298 | skb->dev = dev; | |
299 | ||
300 | /* save this skb for tx interrupt echo handling */ | |
301 | priv->echo_skb[idx] = skb; | |
302 | } else { | |
303 | /* locking problem with netif_stop_queue() ?? */ | |
304 | dev_err(dev->dev.parent, "%s: BUG! echo_skb is occupied!\n", | |
305 | __func__); | |
306 | kfree_skb(skb); | |
307 | } | |
308 | } | |
309 | EXPORT_SYMBOL_GPL(can_put_echo_skb); | |
310 | ||
311 | /* | |
312 | * Get the skb from the stack and loop it back locally | |
313 | * | |
314 | * The function is typically called when the TX done interrupt | |
315 | * is handled in the device driver. The driver must protect | |
316 | * access to priv->echo_skb, if necessary. | |
317 | */ | |
a6e4bc53 | 318 | void can_get_echo_skb(struct net_device *dev, unsigned int idx) |
39549eef WG |
319 | { |
320 | struct can_priv *priv = netdev_priv(dev); | |
321 | ||
a6e4bc53 WG |
322 | BUG_ON(idx >= priv->echo_skb_max); |
323 | ||
39e3ab6f | 324 | if (priv->echo_skb[idx]) { |
39549eef WG |
325 | netif_rx(priv->echo_skb[idx]); |
326 | priv->echo_skb[idx] = NULL; | |
327 | } | |
328 | } | |
329 | EXPORT_SYMBOL_GPL(can_get_echo_skb); | |
330 | ||
39e3ab6f WG |
331 | /* |
332 | * Remove the skb from the stack and free it. | |
333 | * | |
334 | * The function is typically called when TX failed. | |
335 | */ | |
a6e4bc53 | 336 | void can_free_echo_skb(struct net_device *dev, unsigned int idx) |
39e3ab6f WG |
337 | { |
338 | struct can_priv *priv = netdev_priv(dev); | |
339 | ||
a6e4bc53 WG |
340 | BUG_ON(idx >= priv->echo_skb_max); |
341 | ||
39e3ab6f WG |
342 | if (priv->echo_skb[idx]) { |
343 | kfree_skb(priv->echo_skb[idx]); | |
344 | priv->echo_skb[idx] = NULL; | |
345 | } | |
346 | } | |
347 | EXPORT_SYMBOL_GPL(can_free_echo_skb); | |
348 | ||
39549eef WG |
349 | /* |
350 | * CAN device restart for bus-off recovery | |
351 | */ | |
352 | void can_restart(unsigned long data) | |
353 | { | |
354 | struct net_device *dev = (struct net_device *)data; | |
355 | struct can_priv *priv = netdev_priv(dev); | |
356 | struct net_device_stats *stats = &dev->stats; | |
357 | struct sk_buff *skb; | |
358 | struct can_frame *cf; | |
359 | int err; | |
360 | ||
361 | BUG_ON(netif_carrier_ok(dev)); | |
362 | ||
363 | /* | |
364 | * No synchronization needed because the device is bus-off and | |
365 | * no messages can come in or go out. | |
366 | */ | |
367 | can_flush_echo_skb(dev); | |
368 | ||
369 | /* send restart message upstream */ | |
7b6856a0 | 370 | skb = alloc_can_err_skb(dev, &cf); |
39549eef WG |
371 | if (skb == NULL) { |
372 | err = -ENOMEM; | |
b3d0df7c | 373 | goto restart; |
39549eef | 374 | } |
7b6856a0 | 375 | cf->can_id |= CAN_ERR_RESTARTED; |
39549eef WG |
376 | |
377 | netif_rx(skb); | |
378 | ||
39549eef WG |
379 | stats->rx_packets++; |
380 | stats->rx_bytes += cf->can_dlc; | |
381 | ||
b3d0df7c | 382 | restart: |
39549eef WG |
383 | dev_dbg(dev->dev.parent, "restarted\n"); |
384 | priv->can_stats.restarts++; | |
385 | ||
386 | /* Now restart the device */ | |
387 | err = priv->do_set_mode(dev, CAN_MODE_START); | |
388 | ||
39549eef WG |
389 | netif_carrier_on(dev); |
390 | if (err) | |
391 | dev_err(dev->dev.parent, "Error %d during restart", err); | |
392 | } | |
393 | ||
394 | int can_restart_now(struct net_device *dev) | |
395 | { | |
396 | struct can_priv *priv = netdev_priv(dev); | |
397 | ||
398 | /* | |
399 | * A manual restart is only permitted if automatic restart is | |
400 | * disabled and the device is in the bus-off state | |
401 | */ | |
402 | if (priv->restart_ms) | |
403 | return -EINVAL; | |
404 | if (priv->state != CAN_STATE_BUS_OFF) | |
405 | return -EBUSY; | |
406 | ||
407 | /* Runs as soon as possible in the timer context */ | |
408 | mod_timer(&priv->restart_timer, jiffies); | |
409 | ||
410 | return 0; | |
411 | } | |
412 | ||
413 | /* | |
414 | * CAN bus-off | |
415 | * | |
416 | * This functions should be called when the device goes bus-off to | |
417 | * tell the netif layer that no more packets can be sent or received. | |
418 | * If enabled, a timer is started to trigger bus-off recovery. | |
419 | */ | |
420 | void can_bus_off(struct net_device *dev) | |
421 | { | |
422 | struct can_priv *priv = netdev_priv(dev); | |
423 | ||
424 | dev_dbg(dev->dev.parent, "bus-off\n"); | |
425 | ||
426 | netif_carrier_off(dev); | |
427 | priv->can_stats.bus_off++; | |
428 | ||
429 | if (priv->restart_ms) | |
430 | mod_timer(&priv->restart_timer, | |
431 | jiffies + (priv->restart_ms * HZ) / 1000); | |
432 | } | |
433 | EXPORT_SYMBOL_GPL(can_bus_off); | |
434 | ||
435 | static void can_setup(struct net_device *dev) | |
436 | { | |
437 | dev->type = ARPHRD_CAN; | |
438 | dev->mtu = sizeof(struct can_frame); | |
439 | dev->hard_header_len = 0; | |
440 | dev->addr_len = 0; | |
441 | dev->tx_queue_len = 10; | |
442 | ||
443 | /* New-style flags. */ | |
444 | dev->flags = IFF_NOARP; | |
445 | dev->features = NETIF_F_NO_CSUM; | |
446 | } | |
447 | ||
7b6856a0 WG |
448 | struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf) |
449 | { | |
450 | struct sk_buff *skb; | |
451 | ||
452 | skb = netdev_alloc_skb(dev, sizeof(struct can_frame)); | |
453 | if (unlikely(!skb)) | |
454 | return NULL; | |
455 | ||
456 | skb->protocol = htons(ETH_P_CAN); | |
457 | skb->pkt_type = PACKET_BROADCAST; | |
458 | skb->ip_summed = CHECKSUM_UNNECESSARY; | |
459 | *cf = (struct can_frame *)skb_put(skb, sizeof(struct can_frame)); | |
460 | memset(*cf, 0, sizeof(struct can_frame)); | |
461 | ||
462 | return skb; | |
463 | } | |
464 | EXPORT_SYMBOL_GPL(alloc_can_skb); | |
465 | ||
466 | struct sk_buff *alloc_can_err_skb(struct net_device *dev, struct can_frame **cf) | |
467 | { | |
468 | struct sk_buff *skb; | |
469 | ||
470 | skb = alloc_can_skb(dev, cf); | |
471 | if (unlikely(!skb)) | |
472 | return NULL; | |
473 | ||
474 | (*cf)->can_id = CAN_ERR_FLAG; | |
475 | (*cf)->can_dlc = CAN_ERR_DLC; | |
476 | ||
477 | return skb; | |
478 | } | |
479 | EXPORT_SYMBOL_GPL(alloc_can_err_skb); | |
480 | ||
39549eef WG |
481 | /* |
482 | * Allocate and setup space for the CAN network device | |
483 | */ | |
a6e4bc53 | 484 | struct net_device *alloc_candev(int sizeof_priv, unsigned int echo_skb_max) |
39549eef WG |
485 | { |
486 | struct net_device *dev; | |
487 | struct can_priv *priv; | |
a6e4bc53 | 488 | int size; |
39549eef | 489 | |
a6e4bc53 WG |
490 | if (echo_skb_max) |
491 | size = ALIGN(sizeof_priv, sizeof(struct sk_buff *)) + | |
492 | echo_skb_max * sizeof(struct sk_buff *); | |
493 | else | |
494 | size = sizeof_priv; | |
495 | ||
496 | dev = alloc_netdev(size, "can%d", can_setup); | |
39549eef WG |
497 | if (!dev) |
498 | return NULL; | |
499 | ||
500 | priv = netdev_priv(dev); | |
501 | ||
a6e4bc53 WG |
502 | if (echo_skb_max) { |
503 | priv->echo_skb_max = echo_skb_max; | |
504 | priv->echo_skb = (void *)priv + | |
505 | ALIGN(sizeof_priv, sizeof(struct sk_buff *)); | |
506 | } | |
507 | ||
39549eef WG |
508 | priv->state = CAN_STATE_STOPPED; |
509 | ||
510 | init_timer(&priv->restart_timer); | |
511 | ||
512 | return dev; | |
513 | } | |
514 | EXPORT_SYMBOL_GPL(alloc_candev); | |
515 | ||
516 | /* | |
517 | * Free space of the CAN network device | |
518 | */ | |
519 | void free_candev(struct net_device *dev) | |
520 | { | |
521 | free_netdev(dev); | |
522 | } | |
523 | EXPORT_SYMBOL_GPL(free_candev); | |
524 | ||
525 | /* | |
526 | * Common open function when the device gets opened. | |
527 | * | |
528 | * This function should be called in the open function of the device | |
529 | * driver. | |
530 | */ | |
531 | int open_candev(struct net_device *dev) | |
532 | { | |
533 | struct can_priv *priv = netdev_priv(dev); | |
534 | ||
535 | if (!priv->bittiming.tq && !priv->bittiming.bitrate) { | |
536 | dev_err(dev->dev.parent, "bit-timing not yet defined\n"); | |
537 | return -EINVAL; | |
538 | } | |
539 | ||
1b0d9224 WG |
540 | /* Switch carrier on if device was stopped while in bus-off state */ |
541 | if (!netif_carrier_ok(dev)) | |
542 | netif_carrier_on(dev); | |
543 | ||
39549eef WG |
544 | setup_timer(&priv->restart_timer, can_restart, (unsigned long)dev); |
545 | ||
546 | return 0; | |
547 | } | |
128ced8f | 548 | EXPORT_SYMBOL_GPL(open_candev); |
39549eef WG |
549 | |
550 | /* | |
551 | * Common close function for cleanup before the device gets closed. | |
552 | * | |
553 | * This function should be called in the close function of the device | |
554 | * driver. | |
555 | */ | |
556 | void close_candev(struct net_device *dev) | |
557 | { | |
558 | struct can_priv *priv = netdev_priv(dev); | |
559 | ||
560 | if (del_timer_sync(&priv->restart_timer)) | |
561 | dev_put(dev); | |
562 | can_flush_echo_skb(dev); | |
563 | } | |
564 | EXPORT_SYMBOL_GPL(close_candev); | |
565 | ||
566 | /* | |
567 | * CAN netlink interface | |
568 | */ | |
569 | static const struct nla_policy can_policy[IFLA_CAN_MAX + 1] = { | |
570 | [IFLA_CAN_STATE] = { .type = NLA_U32 }, | |
571 | [IFLA_CAN_CTRLMODE] = { .len = sizeof(struct can_ctrlmode) }, | |
572 | [IFLA_CAN_RESTART_MS] = { .type = NLA_U32 }, | |
573 | [IFLA_CAN_RESTART] = { .type = NLA_U32 }, | |
574 | [IFLA_CAN_BITTIMING] = { .len = sizeof(struct can_bittiming) }, | |
575 | [IFLA_CAN_BITTIMING_CONST] | |
576 | = { .len = sizeof(struct can_bittiming_const) }, | |
577 | [IFLA_CAN_CLOCK] = { .len = sizeof(struct can_clock) }, | |
52c793f2 | 578 | [IFLA_CAN_BERR_COUNTER] = { .len = sizeof(struct can_berr_counter) }, |
39549eef WG |
579 | }; |
580 | ||
581 | static int can_changelink(struct net_device *dev, | |
582 | struct nlattr *tb[], struct nlattr *data[]) | |
583 | { | |
584 | struct can_priv *priv = netdev_priv(dev); | |
585 | int err; | |
586 | ||
587 | /* We need synchronization with dev->stop() */ | |
588 | ASSERT_RTNL(); | |
589 | ||
590 | if (data[IFLA_CAN_CTRLMODE]) { | |
591 | struct can_ctrlmode *cm; | |
592 | ||
593 | /* Do not allow changing controller mode while running */ | |
594 | if (dev->flags & IFF_UP) | |
595 | return -EBUSY; | |
596 | cm = nla_data(data[IFLA_CAN_CTRLMODE]); | |
ad72c347 CP |
597 | if (cm->flags & ~priv->ctrlmode_supported) |
598 | return -EOPNOTSUPP; | |
39549eef WG |
599 | priv->ctrlmode &= ~cm->mask; |
600 | priv->ctrlmode |= cm->flags; | |
601 | } | |
602 | ||
603 | if (data[IFLA_CAN_BITTIMING]) { | |
604 | struct can_bittiming bt; | |
605 | ||
606 | /* Do not allow changing bittiming while running */ | |
607 | if (dev->flags & IFF_UP) | |
608 | return -EBUSY; | |
609 | memcpy(&bt, nla_data(data[IFLA_CAN_BITTIMING]), sizeof(bt)); | |
610 | if ((!bt.bitrate && !bt.tq) || (bt.bitrate && bt.tq)) | |
611 | return -EINVAL; | |
612 | err = can_get_bittiming(dev, &bt); | |
613 | if (err) | |
614 | return err; | |
615 | memcpy(&priv->bittiming, &bt, sizeof(bt)); | |
616 | ||
617 | if (priv->do_set_bittiming) { | |
618 | /* Finally, set the bit-timing registers */ | |
619 | err = priv->do_set_bittiming(dev); | |
620 | if (err) | |
621 | return err; | |
622 | } | |
623 | } | |
624 | ||
625 | if (data[IFLA_CAN_RESTART_MS]) { | |
626 | /* Do not allow changing restart delay while running */ | |
627 | if (dev->flags & IFF_UP) | |
628 | return -EBUSY; | |
629 | priv->restart_ms = nla_get_u32(data[IFLA_CAN_RESTART_MS]); | |
630 | } | |
631 | ||
632 | if (data[IFLA_CAN_RESTART]) { | |
633 | /* Do not allow a restart while not running */ | |
634 | if (!(dev->flags & IFF_UP)) | |
635 | return -EINVAL; | |
636 | err = can_restart_now(dev); | |
637 | if (err) | |
638 | return err; | |
639 | } | |
640 | ||
641 | return 0; | |
642 | } | |
643 | ||
53a0ef86 WG |
644 | static size_t can_get_size(const struct net_device *dev) |
645 | { | |
646 | struct can_priv *priv = netdev_priv(dev); | |
647 | size_t size; | |
648 | ||
649 | size = nla_total_size(sizeof(u32)); /* IFLA_CAN_STATE */ | |
650 | size += sizeof(struct can_ctrlmode); /* IFLA_CAN_CTRLMODE */ | |
651 | size += nla_total_size(sizeof(u32)); /* IFLA_CAN_RESTART_MS */ | |
652 | size += sizeof(struct can_bittiming); /* IFLA_CAN_BITTIMING */ | |
653 | size += sizeof(struct can_clock); /* IFLA_CAN_CLOCK */ | |
52c793f2 WG |
654 | if (priv->do_get_berr_counter) /* IFLA_CAN_BERR_COUNTER */ |
655 | size += sizeof(struct can_berr_counter); | |
53a0ef86 WG |
656 | if (priv->bittiming_const) /* IFLA_CAN_BITTIMING_CONST */ |
657 | size += sizeof(struct can_bittiming_const); | |
658 | ||
659 | return size; | |
660 | } | |
661 | ||
39549eef WG |
662 | static int can_fill_info(struct sk_buff *skb, const struct net_device *dev) |
663 | { | |
664 | struct can_priv *priv = netdev_priv(dev); | |
665 | struct can_ctrlmode cm = {.flags = priv->ctrlmode}; | |
52c793f2 | 666 | struct can_berr_counter bec; |
39549eef WG |
667 | enum can_state state = priv->state; |
668 | ||
669 | if (priv->do_get_state) | |
670 | priv->do_get_state(dev, &state); | |
671 | NLA_PUT_U32(skb, IFLA_CAN_STATE, state); | |
672 | NLA_PUT(skb, IFLA_CAN_CTRLMODE, sizeof(cm), &cm); | |
673 | NLA_PUT_U32(skb, IFLA_CAN_RESTART_MS, priv->restart_ms); | |
674 | NLA_PUT(skb, IFLA_CAN_BITTIMING, | |
675 | sizeof(priv->bittiming), &priv->bittiming); | |
676 | NLA_PUT(skb, IFLA_CAN_CLOCK, sizeof(cm), &priv->clock); | |
52c793f2 WG |
677 | if (priv->do_get_berr_counter && !priv->do_get_berr_counter(dev, &bec)) |
678 | NLA_PUT(skb, IFLA_CAN_BERR_COUNTER, sizeof(bec), &bec); | |
39549eef WG |
679 | if (priv->bittiming_const) |
680 | NLA_PUT(skb, IFLA_CAN_BITTIMING_CONST, | |
681 | sizeof(*priv->bittiming_const), priv->bittiming_const); | |
682 | ||
683 | return 0; | |
684 | ||
685 | nla_put_failure: | |
686 | return -EMSGSIZE; | |
687 | } | |
688 | ||
55369c0a WG |
689 | static size_t can_get_xstats_size(const struct net_device *dev) |
690 | { | |
691 | return sizeof(struct can_device_stats); | |
692 | } | |
693 | ||
39549eef WG |
694 | static int can_fill_xstats(struct sk_buff *skb, const struct net_device *dev) |
695 | { | |
696 | struct can_priv *priv = netdev_priv(dev); | |
697 | ||
698 | NLA_PUT(skb, IFLA_INFO_XSTATS, | |
699 | sizeof(priv->can_stats), &priv->can_stats); | |
700 | ||
701 | return 0; | |
702 | ||
703 | nla_put_failure: | |
704 | return -EMSGSIZE; | |
705 | } | |
706 | ||
81adee47 | 707 | static int can_newlink(struct net *src_net, struct net_device *dev, |
993e6f2f OH |
708 | struct nlattr *tb[], struct nlattr *data[]) |
709 | { | |
710 | return -EOPNOTSUPP; | |
711 | } | |
712 | ||
39549eef WG |
713 | static struct rtnl_link_ops can_link_ops __read_mostly = { |
714 | .kind = "can", | |
715 | .maxtype = IFLA_CAN_MAX, | |
716 | .policy = can_policy, | |
717 | .setup = can_setup, | |
993e6f2f | 718 | .newlink = can_newlink, |
39549eef | 719 | .changelink = can_changelink, |
53a0ef86 | 720 | .get_size = can_get_size, |
39549eef | 721 | .fill_info = can_fill_info, |
55369c0a | 722 | .get_xstats_size = can_get_xstats_size, |
39549eef WG |
723 | .fill_xstats = can_fill_xstats, |
724 | }; | |
725 | ||
726 | /* | |
727 | * Register the CAN network device | |
728 | */ | |
729 | int register_candev(struct net_device *dev) | |
730 | { | |
731 | dev->rtnl_link_ops = &can_link_ops; | |
732 | return register_netdev(dev); | |
733 | } | |
734 | EXPORT_SYMBOL_GPL(register_candev); | |
735 | ||
736 | /* | |
737 | * Unregister the CAN network device | |
738 | */ | |
739 | void unregister_candev(struct net_device *dev) | |
740 | { | |
741 | unregister_netdev(dev); | |
742 | } | |
743 | EXPORT_SYMBOL_GPL(unregister_candev); | |
744 | ||
745 | static __init int can_dev_init(void) | |
746 | { | |
747 | int err; | |
748 | ||
749 | err = rtnl_link_register(&can_link_ops); | |
750 | if (!err) | |
751 | printk(KERN_INFO MOD_DESC "\n"); | |
752 | ||
753 | return err; | |
754 | } | |
755 | module_init(can_dev_init); | |
756 | ||
757 | static __exit void can_dev_exit(void) | |
758 | { | |
759 | rtnl_link_unregister(&can_link_ops); | |
760 | } | |
761 | module_exit(can_dev_exit); | |
762 | ||
763 | MODULE_ALIAS_RTNL_LINK("can"); |