Commit | Line | Data |
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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> | |
156c2bb9 | 27 | #include <linux/can/skb.h> |
39549eef | 28 | #include <linux/can/netlink.h> |
a1ef7bd9 | 29 | #include <linux/can/led.h> |
39549eef WG |
30 | #include <net/rtnetlink.h> |
31 | ||
32 | #define MOD_DESC "CAN device driver interface" | |
33 | ||
34 | MODULE_DESCRIPTION(MOD_DESC); | |
35 | MODULE_LICENSE("GPL v2"); | |
36 | MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>"); | |
37 | ||
1e0625fa OH |
38 | /* CAN DLC to real data length conversion helpers */ |
39 | ||
40 | static const u8 dlc2len[] = {0, 1, 2, 3, 4, 5, 6, 7, | |
41 | 8, 12, 16, 20, 24, 32, 48, 64}; | |
42 | ||
43 | /* get data length from can_dlc with sanitized can_dlc */ | |
44 | u8 can_dlc2len(u8 can_dlc) | |
45 | { | |
46 | return dlc2len[can_dlc & 0x0F]; | |
47 | } | |
48 | EXPORT_SYMBOL_GPL(can_dlc2len); | |
49 | ||
50 | static const u8 len2dlc[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, /* 0 - 8 */ | |
51 | 9, 9, 9, 9, /* 9 - 12 */ | |
52 | 10, 10, 10, 10, /* 13 - 16 */ | |
53 | 11, 11, 11, 11, /* 17 - 20 */ | |
54 | 12, 12, 12, 12, /* 21 - 24 */ | |
55 | 13, 13, 13, 13, 13, 13, 13, 13, /* 25 - 32 */ | |
56 | 14, 14, 14, 14, 14, 14, 14, 14, /* 33 - 40 */ | |
57 | 14, 14, 14, 14, 14, 14, 14, 14, /* 41 - 48 */ | |
58 | 15, 15, 15, 15, 15, 15, 15, 15, /* 49 - 56 */ | |
59 | 15, 15, 15, 15, 15, 15, 15, 15}; /* 57 - 64 */ | |
60 | ||
61 | /* map the sanitized data length to an appropriate data length code */ | |
62 | u8 can_len2dlc(u8 len) | |
63 | { | |
64 | if (unlikely(len > 64)) | |
65 | return 0xF; | |
66 | ||
67 | return len2dlc[len]; | |
68 | } | |
69 | EXPORT_SYMBOL_GPL(can_len2dlc); | |
70 | ||
39549eef WG |
71 | #ifdef CONFIG_CAN_CALC_BITTIMING |
72 | #define CAN_CALC_MAX_ERROR 50 /* in one-tenth of a percent */ | |
73 | ||
74 | /* | |
75 | * Bit-timing calculation derived from: | |
76 | * | |
77 | * Code based on LinCAN sources and H8S2638 project | |
78 | * Copyright 2004-2006 Pavel Pisa - DCE FELK CVUT cz | |
79 | * Copyright 2005 Stanislav Marek | |
80 | * email: pisa@cmp.felk.cvut.cz | |
81 | * | |
82 | * Calculates proper bit-timing parameters for a specified bit-rate | |
83 | * and sample-point, which can then be used to set the bit-timing | |
84 | * registers of the CAN controller. You can find more information | |
85 | * in the header file linux/can/netlink.h. | |
86 | */ | |
87 | static int can_update_spt(const struct can_bittiming_const *btc, | |
88 | int sampl_pt, int tseg, int *tseg1, int *tseg2) | |
89 | { | |
90 | *tseg2 = tseg + 1 - (sampl_pt * (tseg + 1)) / 1000; | |
91 | if (*tseg2 < btc->tseg2_min) | |
92 | *tseg2 = btc->tseg2_min; | |
93 | if (*tseg2 > btc->tseg2_max) | |
94 | *tseg2 = btc->tseg2_max; | |
95 | *tseg1 = tseg - *tseg2; | |
96 | if (*tseg1 > btc->tseg1_max) { | |
97 | *tseg1 = btc->tseg1_max; | |
98 | *tseg2 = tseg - *tseg1; | |
99 | } | |
100 | return 1000 * (tseg + 1 - *tseg2) / (tseg + 1); | |
101 | } | |
102 | ||
103 | static int can_calc_bittiming(struct net_device *dev, struct can_bittiming *bt) | |
104 | { | |
105 | struct can_priv *priv = netdev_priv(dev); | |
106 | const struct can_bittiming_const *btc = priv->bittiming_const; | |
107 | long rate, best_rate = 0; | |
108 | long best_error = 1000000000, error = 0; | |
109 | int best_tseg = 0, best_brp = 0, brp = 0; | |
110 | int tsegall, tseg = 0, tseg1 = 0, tseg2 = 0; | |
111 | int spt_error = 1000, spt = 0, sampl_pt; | |
112 | u64 v64; | |
113 | ||
114 | if (!priv->bittiming_const) | |
115 | return -ENOTSUPP; | |
116 | ||
117 | /* Use CIA recommended sample points */ | |
118 | if (bt->sample_point) { | |
119 | sampl_pt = bt->sample_point; | |
120 | } else { | |
121 | if (bt->bitrate > 800000) | |
122 | sampl_pt = 750; | |
123 | else if (bt->bitrate > 500000) | |
124 | sampl_pt = 800; | |
125 | else | |
126 | sampl_pt = 875; | |
127 | } | |
128 | ||
129 | /* tseg even = round down, odd = round up */ | |
130 | for (tseg = (btc->tseg1_max + btc->tseg2_max) * 2 + 1; | |
131 | tseg >= (btc->tseg1_min + btc->tseg2_min) * 2; tseg--) { | |
132 | tsegall = 1 + tseg / 2; | |
133 | /* Compute all possible tseg choices (tseg=tseg1+tseg2) */ | |
134 | brp = priv->clock.freq / (tsegall * bt->bitrate) + tseg % 2; | |
135 | /* chose brp step which is possible in system */ | |
136 | brp = (brp / btc->brp_inc) * btc->brp_inc; | |
137 | if ((brp < btc->brp_min) || (brp > btc->brp_max)) | |
138 | continue; | |
139 | rate = priv->clock.freq / (brp * tsegall); | |
140 | error = bt->bitrate - rate; | |
141 | /* tseg brp biterror */ | |
142 | if (error < 0) | |
143 | error = -error; | |
144 | if (error > best_error) | |
145 | continue; | |
146 | best_error = error; | |
147 | if (error == 0) { | |
148 | spt = can_update_spt(btc, sampl_pt, tseg / 2, | |
149 | &tseg1, &tseg2); | |
150 | error = sampl_pt - spt; | |
151 | if (error < 0) | |
152 | error = -error; | |
153 | if (error > spt_error) | |
154 | continue; | |
155 | spt_error = error; | |
156 | } | |
157 | best_tseg = tseg / 2; | |
158 | best_brp = brp; | |
159 | best_rate = rate; | |
160 | if (error == 0) | |
161 | break; | |
162 | } | |
163 | ||
164 | if (best_error) { | |
165 | /* Error in one-tenth of a percent */ | |
166 | error = (best_error * 1000) / bt->bitrate; | |
167 | if (error > CAN_CALC_MAX_ERROR) { | |
aabdfd6a WG |
168 | netdev_err(dev, |
169 | "bitrate error %ld.%ld%% too high\n", | |
170 | error / 10, error % 10); | |
39549eef WG |
171 | return -EDOM; |
172 | } else { | |
aabdfd6a WG |
173 | netdev_warn(dev, "bitrate error %ld.%ld%%\n", |
174 | error / 10, error % 10); | |
39549eef WG |
175 | } |
176 | } | |
177 | ||
178 | /* real sample point */ | |
179 | bt->sample_point = can_update_spt(btc, sampl_pt, best_tseg, | |
180 | &tseg1, &tseg2); | |
181 | ||
182 | v64 = (u64)best_brp * 1000000000UL; | |
183 | do_div(v64, priv->clock.freq); | |
184 | bt->tq = (u32)v64; | |
185 | bt->prop_seg = tseg1 / 2; | |
186 | bt->phase_seg1 = tseg1 - bt->prop_seg; | |
187 | bt->phase_seg2 = tseg2; | |
2e114374 OH |
188 | |
189 | /* check for sjw user settings */ | |
190 | if (!bt->sjw || !btc->sjw_max) | |
191 | bt->sjw = 1; | |
192 | else { | |
193 | /* bt->sjw is at least 1 -> sanitize upper bound to sjw_max */ | |
194 | if (bt->sjw > btc->sjw_max) | |
195 | bt->sjw = btc->sjw_max; | |
196 | /* bt->sjw must not be higher than tseg2 */ | |
197 | if (tseg2 < bt->sjw) | |
198 | bt->sjw = tseg2; | |
199 | } | |
200 | ||
39549eef WG |
201 | bt->brp = best_brp; |
202 | /* real bit-rate */ | |
203 | bt->bitrate = priv->clock.freq / (bt->brp * (tseg1 + tseg2 + 1)); | |
204 | ||
205 | return 0; | |
206 | } | |
207 | #else /* !CONFIG_CAN_CALC_BITTIMING */ | |
208 | static int can_calc_bittiming(struct net_device *dev, struct can_bittiming *bt) | |
209 | { | |
aabdfd6a | 210 | netdev_err(dev, "bit-timing calculation not available\n"); |
39549eef WG |
211 | return -EINVAL; |
212 | } | |
213 | #endif /* CONFIG_CAN_CALC_BITTIMING */ | |
214 | ||
215 | /* | |
216 | * Checks the validity of the specified bit-timing parameters prop_seg, | |
217 | * phase_seg1, phase_seg2 and sjw and tries to determine the bitrate | |
218 | * prescaler value brp. You can find more information in the header | |
219 | * file linux/can/netlink.h. | |
220 | */ | |
221 | static int can_fixup_bittiming(struct net_device *dev, struct can_bittiming *bt) | |
222 | { | |
223 | struct can_priv *priv = netdev_priv(dev); | |
224 | const struct can_bittiming_const *btc = priv->bittiming_const; | |
225 | int tseg1, alltseg; | |
226 | u64 brp64; | |
227 | ||
228 | if (!priv->bittiming_const) | |
229 | return -ENOTSUPP; | |
230 | ||
231 | tseg1 = bt->prop_seg + bt->phase_seg1; | |
232 | if (!bt->sjw) | |
233 | bt->sjw = 1; | |
234 | if (bt->sjw > btc->sjw_max || | |
235 | tseg1 < btc->tseg1_min || tseg1 > btc->tseg1_max || | |
236 | bt->phase_seg2 < btc->tseg2_min || bt->phase_seg2 > btc->tseg2_max) | |
237 | return -ERANGE; | |
238 | ||
239 | brp64 = (u64)priv->clock.freq * (u64)bt->tq; | |
240 | if (btc->brp_inc > 1) | |
241 | do_div(brp64, btc->brp_inc); | |
242 | brp64 += 500000000UL - 1; | |
243 | do_div(brp64, 1000000000UL); /* the practicable BRP */ | |
244 | if (btc->brp_inc > 1) | |
245 | brp64 *= btc->brp_inc; | |
246 | bt->brp = (u32)brp64; | |
247 | ||
248 | if (bt->brp < btc->brp_min || bt->brp > btc->brp_max) | |
249 | return -EINVAL; | |
250 | ||
251 | alltseg = bt->prop_seg + bt->phase_seg1 + bt->phase_seg2 + 1; | |
252 | bt->bitrate = priv->clock.freq / (bt->brp * alltseg); | |
253 | bt->sample_point = ((tseg1 + 1) * 1000) / alltseg; | |
254 | ||
255 | return 0; | |
256 | } | |
257 | ||
61463a30 | 258 | static int can_get_bittiming(struct net_device *dev, struct can_bittiming *bt) |
39549eef WG |
259 | { |
260 | struct can_priv *priv = netdev_priv(dev); | |
261 | int err; | |
262 | ||
263 | /* Check if the CAN device has bit-timing parameters */ | |
264 | if (priv->bittiming_const) { | |
265 | ||
266 | /* Non-expert mode? Check if the bitrate has been pre-defined */ | |
267 | if (!bt->tq) | |
268 | /* Determine bit-timing parameters */ | |
269 | err = can_calc_bittiming(dev, bt); | |
270 | else | |
271 | /* Check bit-timing params and calculate proper brp */ | |
272 | err = can_fixup_bittiming(dev, bt); | |
273 | if (err) | |
274 | return err; | |
275 | } | |
276 | ||
277 | return 0; | |
278 | } | |
279 | ||
280 | /* | |
281 | * Local echo of CAN messages | |
282 | * | |
283 | * CAN network devices *should* support a local echo functionality | |
284 | * (see Documentation/networking/can.txt). To test the handling of CAN | |
285 | * interfaces that do not support the local echo both driver types are | |
286 | * implemented. In the case that the driver does not support the echo | |
287 | * the IFF_ECHO remains clear in dev->flags. This causes the PF_CAN core | |
288 | * to perform the echo as a fallback solution. | |
289 | */ | |
290 | static void can_flush_echo_skb(struct net_device *dev) | |
291 | { | |
292 | struct can_priv *priv = netdev_priv(dev); | |
293 | struct net_device_stats *stats = &dev->stats; | |
294 | int i; | |
295 | ||
a6e4bc53 | 296 | for (i = 0; i < priv->echo_skb_max; i++) { |
39549eef WG |
297 | if (priv->echo_skb[i]) { |
298 | kfree_skb(priv->echo_skb[i]); | |
299 | priv->echo_skb[i] = NULL; | |
300 | stats->tx_dropped++; | |
301 | stats->tx_aborted_errors++; | |
302 | } | |
303 | } | |
304 | } | |
305 | ||
306 | /* | |
307 | * Put the skb on the stack to be looped backed locally lateron | |
308 | * | |
309 | * The function is typically called in the start_xmit function | |
310 | * of the device driver. The driver must protect access to | |
311 | * priv->echo_skb, if necessary. | |
312 | */ | |
a6e4bc53 WG |
313 | void can_put_echo_skb(struct sk_buff *skb, struct net_device *dev, |
314 | unsigned int idx) | |
39549eef WG |
315 | { |
316 | struct can_priv *priv = netdev_priv(dev); | |
317 | ||
a6e4bc53 WG |
318 | BUG_ON(idx >= priv->echo_skb_max); |
319 | ||
39549eef WG |
320 | /* check flag whether this packet has to be looped back */ |
321 | if (!(dev->flags & IFF_ECHO) || skb->pkt_type != PACKET_LOOPBACK) { | |
322 | kfree_skb(skb); | |
323 | return; | |
324 | } | |
325 | ||
326 | if (!priv->echo_skb[idx]) { | |
327 | struct sock *srcsk = skb->sk; | |
328 | ||
329 | if (atomic_read(&skb->users) != 1) { | |
330 | struct sk_buff *old_skb = skb; | |
331 | ||
332 | skb = skb_clone(old_skb, GFP_ATOMIC); | |
333 | kfree_skb(old_skb); | |
334 | if (!skb) | |
335 | return; | |
336 | } else | |
337 | skb_orphan(skb); | |
338 | ||
339 | skb->sk = srcsk; | |
340 | ||
341 | /* make settings for echo to reduce code in irq context */ | |
342 | skb->protocol = htons(ETH_P_CAN); | |
343 | skb->pkt_type = PACKET_BROADCAST; | |
344 | skb->ip_summed = CHECKSUM_UNNECESSARY; | |
345 | skb->dev = dev; | |
346 | ||
347 | /* save this skb for tx interrupt echo handling */ | |
348 | priv->echo_skb[idx] = skb; | |
349 | } else { | |
350 | /* locking problem with netif_stop_queue() ?? */ | |
aabdfd6a | 351 | netdev_err(dev, "%s: BUG! echo_skb is occupied!\n", __func__); |
39549eef WG |
352 | kfree_skb(skb); |
353 | } | |
354 | } | |
355 | EXPORT_SYMBOL_GPL(can_put_echo_skb); | |
356 | ||
357 | /* | |
358 | * Get the skb from the stack and loop it back locally | |
359 | * | |
360 | * The function is typically called when the TX done interrupt | |
361 | * is handled in the device driver. The driver must protect | |
362 | * access to priv->echo_skb, if necessary. | |
363 | */ | |
cf5046b3 | 364 | unsigned int can_get_echo_skb(struct net_device *dev, unsigned int idx) |
39549eef WG |
365 | { |
366 | struct can_priv *priv = netdev_priv(dev); | |
367 | ||
a6e4bc53 WG |
368 | BUG_ON(idx >= priv->echo_skb_max); |
369 | ||
39e3ab6f | 370 | if (priv->echo_skb[idx]) { |
cf5046b3 MKB |
371 | struct sk_buff *skb = priv->echo_skb[idx]; |
372 | struct can_frame *cf = (struct can_frame *)skb->data; | |
373 | u8 dlc = cf->can_dlc; | |
374 | ||
39549eef WG |
375 | netif_rx(priv->echo_skb[idx]); |
376 | priv->echo_skb[idx] = NULL; | |
cf5046b3 MKB |
377 | |
378 | return dlc; | |
39549eef | 379 | } |
cf5046b3 MKB |
380 | |
381 | return 0; | |
39549eef WG |
382 | } |
383 | EXPORT_SYMBOL_GPL(can_get_echo_skb); | |
384 | ||
39e3ab6f WG |
385 | /* |
386 | * Remove the skb from the stack and free it. | |
387 | * | |
388 | * The function is typically called when TX failed. | |
389 | */ | |
a6e4bc53 | 390 | void can_free_echo_skb(struct net_device *dev, unsigned int idx) |
39e3ab6f WG |
391 | { |
392 | struct can_priv *priv = netdev_priv(dev); | |
393 | ||
a6e4bc53 WG |
394 | BUG_ON(idx >= priv->echo_skb_max); |
395 | ||
39e3ab6f WG |
396 | if (priv->echo_skb[idx]) { |
397 | kfree_skb(priv->echo_skb[idx]); | |
398 | priv->echo_skb[idx] = NULL; | |
399 | } | |
400 | } | |
401 | EXPORT_SYMBOL_GPL(can_free_echo_skb); | |
402 | ||
39549eef WG |
403 | /* |
404 | * CAN device restart for bus-off recovery | |
405 | */ | |
77fc95a3 | 406 | static void can_restart(unsigned long data) |
39549eef WG |
407 | { |
408 | struct net_device *dev = (struct net_device *)data; | |
409 | struct can_priv *priv = netdev_priv(dev); | |
410 | struct net_device_stats *stats = &dev->stats; | |
411 | struct sk_buff *skb; | |
412 | struct can_frame *cf; | |
413 | int err; | |
414 | ||
415 | BUG_ON(netif_carrier_ok(dev)); | |
416 | ||
417 | /* | |
418 | * No synchronization needed because the device is bus-off and | |
419 | * no messages can come in or go out. | |
420 | */ | |
421 | can_flush_echo_skb(dev); | |
422 | ||
423 | /* send restart message upstream */ | |
7b6856a0 | 424 | skb = alloc_can_err_skb(dev, &cf); |
39549eef WG |
425 | if (skb == NULL) { |
426 | err = -ENOMEM; | |
b3d0df7c | 427 | goto restart; |
39549eef | 428 | } |
7b6856a0 | 429 | cf->can_id |= CAN_ERR_RESTARTED; |
39549eef WG |
430 | |
431 | netif_rx(skb); | |
432 | ||
39549eef WG |
433 | stats->rx_packets++; |
434 | stats->rx_bytes += cf->can_dlc; | |
435 | ||
b3d0df7c | 436 | restart: |
aabdfd6a | 437 | netdev_dbg(dev, "restarted\n"); |
39549eef WG |
438 | priv->can_stats.restarts++; |
439 | ||
440 | /* Now restart the device */ | |
441 | err = priv->do_set_mode(dev, CAN_MODE_START); | |
442 | ||
39549eef WG |
443 | netif_carrier_on(dev); |
444 | if (err) | |
aabdfd6a | 445 | netdev_err(dev, "Error %d during restart", err); |
39549eef WG |
446 | } |
447 | ||
448 | int can_restart_now(struct net_device *dev) | |
449 | { | |
450 | struct can_priv *priv = netdev_priv(dev); | |
451 | ||
452 | /* | |
453 | * A manual restart is only permitted if automatic restart is | |
454 | * disabled and the device is in the bus-off state | |
455 | */ | |
456 | if (priv->restart_ms) | |
457 | return -EINVAL; | |
458 | if (priv->state != CAN_STATE_BUS_OFF) | |
459 | return -EBUSY; | |
460 | ||
461 | /* Runs as soon as possible in the timer context */ | |
462 | mod_timer(&priv->restart_timer, jiffies); | |
463 | ||
464 | return 0; | |
465 | } | |
466 | ||
467 | /* | |
468 | * CAN bus-off | |
469 | * | |
470 | * This functions should be called when the device goes bus-off to | |
471 | * tell the netif layer that no more packets can be sent or received. | |
472 | * If enabled, a timer is started to trigger bus-off recovery. | |
473 | */ | |
474 | void can_bus_off(struct net_device *dev) | |
475 | { | |
476 | struct can_priv *priv = netdev_priv(dev); | |
477 | ||
aabdfd6a | 478 | netdev_dbg(dev, "bus-off\n"); |
39549eef WG |
479 | |
480 | netif_carrier_off(dev); | |
481 | priv->can_stats.bus_off++; | |
482 | ||
483 | if (priv->restart_ms) | |
484 | mod_timer(&priv->restart_timer, | |
485 | jiffies + (priv->restart_ms * HZ) / 1000); | |
486 | } | |
487 | EXPORT_SYMBOL_GPL(can_bus_off); | |
488 | ||
489 | static void can_setup(struct net_device *dev) | |
490 | { | |
491 | dev->type = ARPHRD_CAN; | |
1e0625fa | 492 | dev->mtu = CAN_MTU; |
39549eef WG |
493 | dev->hard_header_len = 0; |
494 | dev->addr_len = 0; | |
495 | dev->tx_queue_len = 10; | |
496 | ||
497 | /* New-style flags. */ | |
498 | dev->flags = IFF_NOARP; | |
34324dc2 | 499 | dev->features = NETIF_F_HW_CSUM; |
39549eef WG |
500 | } |
501 | ||
7b6856a0 WG |
502 | struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf) |
503 | { | |
504 | struct sk_buff *skb; | |
505 | ||
156c2bb9 OH |
506 | skb = netdev_alloc_skb(dev, sizeof(struct can_skb_priv) + |
507 | sizeof(struct can_frame)); | |
7b6856a0 WG |
508 | if (unlikely(!skb)) |
509 | return NULL; | |
510 | ||
511 | skb->protocol = htons(ETH_P_CAN); | |
512 | skb->pkt_type = PACKET_BROADCAST; | |
513 | skb->ip_summed = CHECKSUM_UNNECESSARY; | |
156c2bb9 | 514 | |
2bf3440d OH |
515 | can_skb_reserve(skb); |
516 | can_skb_prv(skb)->ifindex = dev->ifindex; | |
156c2bb9 | 517 | |
7b6856a0 WG |
518 | *cf = (struct can_frame *)skb_put(skb, sizeof(struct can_frame)); |
519 | memset(*cf, 0, sizeof(struct can_frame)); | |
520 | ||
521 | return skb; | |
522 | } | |
523 | EXPORT_SYMBOL_GPL(alloc_can_skb); | |
524 | ||
525 | struct sk_buff *alloc_can_err_skb(struct net_device *dev, struct can_frame **cf) | |
526 | { | |
527 | struct sk_buff *skb; | |
528 | ||
529 | skb = alloc_can_skb(dev, cf); | |
530 | if (unlikely(!skb)) | |
531 | return NULL; | |
532 | ||
533 | (*cf)->can_id = CAN_ERR_FLAG; | |
534 | (*cf)->can_dlc = CAN_ERR_DLC; | |
535 | ||
536 | return skb; | |
537 | } | |
538 | EXPORT_SYMBOL_GPL(alloc_can_err_skb); | |
539 | ||
39549eef WG |
540 | /* |
541 | * Allocate and setup space for the CAN network device | |
542 | */ | |
a6e4bc53 | 543 | struct net_device *alloc_candev(int sizeof_priv, unsigned int echo_skb_max) |
39549eef WG |
544 | { |
545 | struct net_device *dev; | |
546 | struct can_priv *priv; | |
a6e4bc53 | 547 | int size; |
39549eef | 548 | |
a6e4bc53 WG |
549 | if (echo_skb_max) |
550 | size = ALIGN(sizeof_priv, sizeof(struct sk_buff *)) + | |
551 | echo_skb_max * sizeof(struct sk_buff *); | |
552 | else | |
553 | size = sizeof_priv; | |
554 | ||
555 | dev = alloc_netdev(size, "can%d", can_setup); | |
39549eef WG |
556 | if (!dev) |
557 | return NULL; | |
558 | ||
559 | priv = netdev_priv(dev); | |
560 | ||
a6e4bc53 WG |
561 | if (echo_skb_max) { |
562 | priv->echo_skb_max = echo_skb_max; | |
563 | priv->echo_skb = (void *)priv + | |
564 | ALIGN(sizeof_priv, sizeof(struct sk_buff *)); | |
565 | } | |
566 | ||
39549eef WG |
567 | priv->state = CAN_STATE_STOPPED; |
568 | ||
569 | init_timer(&priv->restart_timer); | |
570 | ||
571 | return dev; | |
572 | } | |
573 | EXPORT_SYMBOL_GPL(alloc_candev); | |
574 | ||
575 | /* | |
576 | * Free space of the CAN network device | |
577 | */ | |
578 | void free_candev(struct net_device *dev) | |
579 | { | |
580 | free_netdev(dev); | |
581 | } | |
582 | EXPORT_SYMBOL_GPL(free_candev); | |
583 | ||
584 | /* | |
585 | * Common open function when the device gets opened. | |
586 | * | |
587 | * This function should be called in the open function of the device | |
588 | * driver. | |
589 | */ | |
590 | int open_candev(struct net_device *dev) | |
591 | { | |
592 | struct can_priv *priv = netdev_priv(dev); | |
593 | ||
594 | if (!priv->bittiming.tq && !priv->bittiming.bitrate) { | |
aabdfd6a | 595 | netdev_err(dev, "bit-timing not yet defined\n"); |
39549eef WG |
596 | return -EINVAL; |
597 | } | |
598 | ||
1b0d9224 WG |
599 | /* Switch carrier on if device was stopped while in bus-off state */ |
600 | if (!netif_carrier_ok(dev)) | |
601 | netif_carrier_on(dev); | |
602 | ||
39549eef WG |
603 | setup_timer(&priv->restart_timer, can_restart, (unsigned long)dev); |
604 | ||
605 | return 0; | |
606 | } | |
128ced8f | 607 | EXPORT_SYMBOL_GPL(open_candev); |
39549eef WG |
608 | |
609 | /* | |
610 | * Common close function for cleanup before the device gets closed. | |
611 | * | |
612 | * This function should be called in the close function of the device | |
613 | * driver. | |
614 | */ | |
615 | void close_candev(struct net_device *dev) | |
616 | { | |
617 | struct can_priv *priv = netdev_priv(dev); | |
618 | ||
ab48b03e | 619 | del_timer_sync(&priv->restart_timer); |
39549eef WG |
620 | can_flush_echo_skb(dev); |
621 | } | |
622 | EXPORT_SYMBOL_GPL(close_candev); | |
623 | ||
624 | /* | |
625 | * CAN netlink interface | |
626 | */ | |
627 | static const struct nla_policy can_policy[IFLA_CAN_MAX + 1] = { | |
628 | [IFLA_CAN_STATE] = { .type = NLA_U32 }, | |
629 | [IFLA_CAN_CTRLMODE] = { .len = sizeof(struct can_ctrlmode) }, | |
630 | [IFLA_CAN_RESTART_MS] = { .type = NLA_U32 }, | |
631 | [IFLA_CAN_RESTART] = { .type = NLA_U32 }, | |
632 | [IFLA_CAN_BITTIMING] = { .len = sizeof(struct can_bittiming) }, | |
633 | [IFLA_CAN_BITTIMING_CONST] | |
634 | = { .len = sizeof(struct can_bittiming_const) }, | |
635 | [IFLA_CAN_CLOCK] = { .len = sizeof(struct can_clock) }, | |
52c793f2 | 636 | [IFLA_CAN_BERR_COUNTER] = { .len = sizeof(struct can_berr_counter) }, |
39549eef WG |
637 | }; |
638 | ||
639 | static int can_changelink(struct net_device *dev, | |
640 | struct nlattr *tb[], struct nlattr *data[]) | |
641 | { | |
642 | struct can_priv *priv = netdev_priv(dev); | |
643 | int err; | |
644 | ||
645 | /* We need synchronization with dev->stop() */ | |
646 | ASSERT_RTNL(); | |
647 | ||
648 | if (data[IFLA_CAN_CTRLMODE]) { | |
649 | struct can_ctrlmode *cm; | |
650 | ||
651 | /* Do not allow changing controller mode while running */ | |
652 | if (dev->flags & IFF_UP) | |
653 | return -EBUSY; | |
654 | cm = nla_data(data[IFLA_CAN_CTRLMODE]); | |
ad72c347 CP |
655 | if (cm->flags & ~priv->ctrlmode_supported) |
656 | return -EOPNOTSUPP; | |
39549eef WG |
657 | priv->ctrlmode &= ~cm->mask; |
658 | priv->ctrlmode |= cm->flags; | |
659 | } | |
660 | ||
661 | if (data[IFLA_CAN_BITTIMING]) { | |
662 | struct can_bittiming bt; | |
663 | ||
664 | /* Do not allow changing bittiming while running */ | |
665 | if (dev->flags & IFF_UP) | |
666 | return -EBUSY; | |
667 | memcpy(&bt, nla_data(data[IFLA_CAN_BITTIMING]), sizeof(bt)); | |
668 | if ((!bt.bitrate && !bt.tq) || (bt.bitrate && bt.tq)) | |
669 | return -EINVAL; | |
670 | err = can_get_bittiming(dev, &bt); | |
671 | if (err) | |
672 | return err; | |
673 | memcpy(&priv->bittiming, &bt, sizeof(bt)); | |
674 | ||
675 | if (priv->do_set_bittiming) { | |
676 | /* Finally, set the bit-timing registers */ | |
677 | err = priv->do_set_bittiming(dev); | |
678 | if (err) | |
679 | return err; | |
680 | } | |
681 | } | |
682 | ||
683 | if (data[IFLA_CAN_RESTART_MS]) { | |
684 | /* Do not allow changing restart delay while running */ | |
685 | if (dev->flags & IFF_UP) | |
686 | return -EBUSY; | |
687 | priv->restart_ms = nla_get_u32(data[IFLA_CAN_RESTART_MS]); | |
688 | } | |
689 | ||
690 | if (data[IFLA_CAN_RESTART]) { | |
691 | /* Do not allow a restart while not running */ | |
692 | if (!(dev->flags & IFF_UP)) | |
693 | return -EINVAL; | |
694 | err = can_restart_now(dev); | |
695 | if (err) | |
696 | return err; | |
697 | } | |
698 | ||
699 | return 0; | |
700 | } | |
701 | ||
53a0ef86 WG |
702 | static size_t can_get_size(const struct net_device *dev) |
703 | { | |
704 | struct can_priv *priv = netdev_priv(dev); | |
705 | size_t size; | |
706 | ||
707 | size = nla_total_size(sizeof(u32)); /* IFLA_CAN_STATE */ | |
fe119a05 | 708 | size += nla_total_size(sizeof(struct can_ctrlmode)); /* IFLA_CAN_CTRLMODE */ |
53a0ef86 | 709 | size += nla_total_size(sizeof(u32)); /* IFLA_CAN_RESTART_MS */ |
fe119a05 MKB |
710 | size += nla_total_size(sizeof(struct can_bittiming)); /* IFLA_CAN_BITTIMING */ |
711 | size += nla_total_size(sizeof(struct can_clock)); /* IFLA_CAN_CLOCK */ | |
52c793f2 | 712 | if (priv->do_get_berr_counter) /* IFLA_CAN_BERR_COUNTER */ |
fe119a05 | 713 | size += nla_total_size(sizeof(struct can_berr_counter)); |
53a0ef86 | 714 | if (priv->bittiming_const) /* IFLA_CAN_BITTIMING_CONST */ |
fe119a05 | 715 | size += nla_total_size(sizeof(struct can_bittiming_const)); |
53a0ef86 WG |
716 | |
717 | return size; | |
718 | } | |
719 | ||
39549eef WG |
720 | static int can_fill_info(struct sk_buff *skb, const struct net_device *dev) |
721 | { | |
722 | struct can_priv *priv = netdev_priv(dev); | |
723 | struct can_ctrlmode cm = {.flags = priv->ctrlmode}; | |
52c793f2 | 724 | struct can_berr_counter bec; |
39549eef WG |
725 | enum can_state state = priv->state; |
726 | ||
727 | if (priv->do_get_state) | |
728 | priv->do_get_state(dev, &state); | |
31e0e328 DM |
729 | if (nla_put_u32(skb, IFLA_CAN_STATE, state) || |
730 | nla_put(skb, IFLA_CAN_CTRLMODE, sizeof(cm), &cm) || | |
731 | nla_put_u32(skb, IFLA_CAN_RESTART_MS, priv->restart_ms) || | |
732 | nla_put(skb, IFLA_CAN_BITTIMING, | |
733 | sizeof(priv->bittiming), &priv->bittiming) || | |
734 | nla_put(skb, IFLA_CAN_CLOCK, sizeof(cm), &priv->clock) || | |
735 | (priv->do_get_berr_counter && | |
736 | !priv->do_get_berr_counter(dev, &bec) && | |
737 | nla_put(skb, IFLA_CAN_BERR_COUNTER, sizeof(bec), &bec)) || | |
738 | (priv->bittiming_const && | |
739 | nla_put(skb, IFLA_CAN_BITTIMING_CONST, | |
740 | sizeof(*priv->bittiming_const), priv->bittiming_const))) | |
741 | goto nla_put_failure; | |
39549eef WG |
742 | return 0; |
743 | ||
744 | nla_put_failure: | |
745 | return -EMSGSIZE; | |
746 | } | |
747 | ||
55369c0a WG |
748 | static size_t can_get_xstats_size(const struct net_device *dev) |
749 | { | |
750 | return sizeof(struct can_device_stats); | |
751 | } | |
752 | ||
39549eef WG |
753 | static int can_fill_xstats(struct sk_buff *skb, const struct net_device *dev) |
754 | { | |
755 | struct can_priv *priv = netdev_priv(dev); | |
756 | ||
31e0e328 DM |
757 | if (nla_put(skb, IFLA_INFO_XSTATS, |
758 | sizeof(priv->can_stats), &priv->can_stats)) | |
759 | goto nla_put_failure; | |
39549eef WG |
760 | return 0; |
761 | ||
762 | nla_put_failure: | |
763 | return -EMSGSIZE; | |
764 | } | |
765 | ||
81adee47 | 766 | static int can_newlink(struct net *src_net, struct net_device *dev, |
993e6f2f OH |
767 | struct nlattr *tb[], struct nlattr *data[]) |
768 | { | |
769 | return -EOPNOTSUPP; | |
770 | } | |
771 | ||
39549eef WG |
772 | static struct rtnl_link_ops can_link_ops __read_mostly = { |
773 | .kind = "can", | |
774 | .maxtype = IFLA_CAN_MAX, | |
775 | .policy = can_policy, | |
776 | .setup = can_setup, | |
993e6f2f | 777 | .newlink = can_newlink, |
39549eef | 778 | .changelink = can_changelink, |
53a0ef86 | 779 | .get_size = can_get_size, |
39549eef | 780 | .fill_info = can_fill_info, |
55369c0a | 781 | .get_xstats_size = can_get_xstats_size, |
39549eef WG |
782 | .fill_xstats = can_fill_xstats, |
783 | }; | |
784 | ||
785 | /* | |
786 | * Register the CAN network device | |
787 | */ | |
788 | int register_candev(struct net_device *dev) | |
789 | { | |
790 | dev->rtnl_link_ops = &can_link_ops; | |
791 | return register_netdev(dev); | |
792 | } | |
793 | EXPORT_SYMBOL_GPL(register_candev); | |
794 | ||
795 | /* | |
796 | * Unregister the CAN network device | |
797 | */ | |
798 | void unregister_candev(struct net_device *dev) | |
799 | { | |
800 | unregister_netdev(dev); | |
801 | } | |
802 | EXPORT_SYMBOL_GPL(unregister_candev); | |
803 | ||
bf03a537 KVD |
804 | /* |
805 | * Test if a network device is a candev based device | |
806 | * and return the can_priv* if so. | |
807 | */ | |
808 | struct can_priv *safe_candev_priv(struct net_device *dev) | |
809 | { | |
810 | if ((dev->type != ARPHRD_CAN) || (dev->rtnl_link_ops != &can_link_ops)) | |
811 | return NULL; | |
812 | ||
813 | return netdev_priv(dev); | |
814 | } | |
815 | EXPORT_SYMBOL_GPL(safe_candev_priv); | |
816 | ||
39549eef WG |
817 | static __init int can_dev_init(void) |
818 | { | |
819 | int err; | |
820 | ||
a1ef7bd9 KVD |
821 | can_led_notifier_init(); |
822 | ||
39549eef WG |
823 | err = rtnl_link_register(&can_link_ops); |
824 | if (!err) | |
825 | printk(KERN_INFO MOD_DESC "\n"); | |
826 | ||
827 | return err; | |
828 | } | |
829 | module_init(can_dev_init); | |
830 | ||
831 | static __exit void can_dev_exit(void) | |
832 | { | |
833 | rtnl_link_unregister(&can_link_ops); | |
a1ef7bd9 KVD |
834 | |
835 | can_led_notifier_exit(); | |
39549eef WG |
836 | } |
837 | module_exit(can_dev_exit); | |
838 | ||
839 | MODULE_ALIAS_RTNL_LINK("can"); |