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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 | |
05780d98 | 16 | * along with this program; if not, see <http://www.gnu.org/licenses/>. |
39549eef WG |
17 | */ |
18 | ||
19 | #include <linux/module.h> | |
20 | #include <linux/kernel.h> | |
5a0e3ad6 | 21 | #include <linux/slab.h> |
39549eef WG |
22 | #include <linux/netdevice.h> |
23 | #include <linux/if_arp.h> | |
24 | #include <linux/can.h> | |
25 | #include <linux/can/dev.h> | |
156c2bb9 | 26 | #include <linux/can/skb.h> |
39549eef | 27 | #include <linux/can/netlink.h> |
a1ef7bd9 | 28 | #include <linux/can/led.h> |
39549eef WG |
29 | #include <net/rtnetlink.h> |
30 | ||
31 | #define MOD_DESC "CAN device driver interface" | |
32 | ||
33 | MODULE_DESCRIPTION(MOD_DESC); | |
34 | MODULE_LICENSE("GPL v2"); | |
35 | MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>"); | |
36 | ||
1e0625fa OH |
37 | /* CAN DLC to real data length conversion helpers */ |
38 | ||
39 | static const u8 dlc2len[] = {0, 1, 2, 3, 4, 5, 6, 7, | |
40 | 8, 12, 16, 20, 24, 32, 48, 64}; | |
41 | ||
42 | /* get data length from can_dlc with sanitized can_dlc */ | |
43 | u8 can_dlc2len(u8 can_dlc) | |
44 | { | |
45 | return dlc2len[can_dlc & 0x0F]; | |
46 | } | |
47 | EXPORT_SYMBOL_GPL(can_dlc2len); | |
48 | ||
49 | static const u8 len2dlc[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, /* 0 - 8 */ | |
50 | 9, 9, 9, 9, /* 9 - 12 */ | |
51 | 10, 10, 10, 10, /* 13 - 16 */ | |
52 | 11, 11, 11, 11, /* 17 - 20 */ | |
53 | 12, 12, 12, 12, /* 21 - 24 */ | |
54 | 13, 13, 13, 13, 13, 13, 13, 13, /* 25 - 32 */ | |
55 | 14, 14, 14, 14, 14, 14, 14, 14, /* 33 - 40 */ | |
56 | 14, 14, 14, 14, 14, 14, 14, 14, /* 41 - 48 */ | |
57 | 15, 15, 15, 15, 15, 15, 15, 15, /* 49 - 56 */ | |
58 | 15, 15, 15, 15, 15, 15, 15, 15}; /* 57 - 64 */ | |
59 | ||
60 | /* map the sanitized data length to an appropriate data length code */ | |
61 | u8 can_len2dlc(u8 len) | |
62 | { | |
63 | if (unlikely(len > 64)) | |
64 | return 0xF; | |
65 | ||
66 | return len2dlc[len]; | |
67 | } | |
68 | EXPORT_SYMBOL_GPL(can_len2dlc); | |
69 | ||
39549eef WG |
70 | #ifdef CONFIG_CAN_CALC_BITTIMING |
71 | #define CAN_CALC_MAX_ERROR 50 /* in one-tenth of a percent */ | |
72 | ||
73 | /* | |
74 | * Bit-timing calculation derived from: | |
75 | * | |
76 | * Code based on LinCAN sources and H8S2638 project | |
77 | * Copyright 2004-2006 Pavel Pisa - DCE FELK CVUT cz | |
78 | * Copyright 2005 Stanislav Marek | |
79 | * email: pisa@cmp.felk.cvut.cz | |
80 | * | |
81 | * Calculates proper bit-timing parameters for a specified bit-rate | |
82 | * and sample-point, which can then be used to set the bit-timing | |
83 | * registers of the CAN controller. You can find more information | |
84 | * in the header file linux/can/netlink.h. | |
85 | */ | |
86 | static int can_update_spt(const struct can_bittiming_const *btc, | |
87 | int sampl_pt, int tseg, int *tseg1, int *tseg2) | |
88 | { | |
89 | *tseg2 = tseg + 1 - (sampl_pt * (tseg + 1)) / 1000; | |
90 | if (*tseg2 < btc->tseg2_min) | |
91 | *tseg2 = btc->tseg2_min; | |
92 | if (*tseg2 > btc->tseg2_max) | |
93 | *tseg2 = btc->tseg2_max; | |
94 | *tseg1 = tseg - *tseg2; | |
95 | if (*tseg1 > btc->tseg1_max) { | |
96 | *tseg1 = btc->tseg1_max; | |
97 | *tseg2 = tseg - *tseg1; | |
98 | } | |
99 | return 1000 * (tseg + 1 - *tseg2) / (tseg + 1); | |
100 | } | |
101 | ||
08da7da4 OH |
102 | static int can_calc_bittiming(struct net_device *dev, struct can_bittiming *bt, |
103 | const struct can_bittiming_const *btc) | |
39549eef WG |
104 | { |
105 | struct can_priv *priv = netdev_priv(dev); | |
39549eef WG |
106 | long rate, best_rate = 0; |
107 | long best_error = 1000000000, error = 0; | |
108 | int best_tseg = 0, best_brp = 0, brp = 0; | |
109 | int tsegall, tseg = 0, tseg1 = 0, tseg2 = 0; | |
110 | int spt_error = 1000, spt = 0, sampl_pt; | |
111 | u64 v64; | |
112 | ||
39549eef WG |
113 | /* Use CIA recommended sample points */ |
114 | if (bt->sample_point) { | |
115 | sampl_pt = bt->sample_point; | |
116 | } else { | |
117 | if (bt->bitrate > 800000) | |
118 | sampl_pt = 750; | |
119 | else if (bt->bitrate > 500000) | |
120 | sampl_pt = 800; | |
121 | else | |
122 | sampl_pt = 875; | |
123 | } | |
124 | ||
125 | /* tseg even = round down, odd = round up */ | |
126 | for (tseg = (btc->tseg1_max + btc->tseg2_max) * 2 + 1; | |
127 | tseg >= (btc->tseg1_min + btc->tseg2_min) * 2; tseg--) { | |
128 | tsegall = 1 + tseg / 2; | |
129 | /* Compute all possible tseg choices (tseg=tseg1+tseg2) */ | |
130 | brp = priv->clock.freq / (tsegall * bt->bitrate) + tseg % 2; | |
131 | /* chose brp step which is possible in system */ | |
132 | brp = (brp / btc->brp_inc) * btc->brp_inc; | |
133 | if ((brp < btc->brp_min) || (brp > btc->brp_max)) | |
134 | continue; | |
135 | rate = priv->clock.freq / (brp * tsegall); | |
136 | error = bt->bitrate - rate; | |
137 | /* tseg brp biterror */ | |
138 | if (error < 0) | |
139 | error = -error; | |
140 | if (error > best_error) | |
141 | continue; | |
142 | best_error = error; | |
143 | if (error == 0) { | |
144 | spt = can_update_spt(btc, sampl_pt, tseg / 2, | |
145 | &tseg1, &tseg2); | |
146 | error = sampl_pt - spt; | |
147 | if (error < 0) | |
148 | error = -error; | |
149 | if (error > spt_error) | |
150 | continue; | |
151 | spt_error = error; | |
152 | } | |
153 | best_tseg = tseg / 2; | |
154 | best_brp = brp; | |
155 | best_rate = rate; | |
156 | if (error == 0) | |
157 | break; | |
158 | } | |
159 | ||
160 | if (best_error) { | |
161 | /* Error in one-tenth of a percent */ | |
162 | error = (best_error * 1000) / bt->bitrate; | |
163 | if (error > CAN_CALC_MAX_ERROR) { | |
aabdfd6a WG |
164 | netdev_err(dev, |
165 | "bitrate error %ld.%ld%% too high\n", | |
166 | error / 10, error % 10); | |
39549eef WG |
167 | return -EDOM; |
168 | } else { | |
aabdfd6a WG |
169 | netdev_warn(dev, "bitrate error %ld.%ld%%\n", |
170 | error / 10, error % 10); | |
39549eef WG |
171 | } |
172 | } | |
173 | ||
174 | /* real sample point */ | |
175 | bt->sample_point = can_update_spt(btc, sampl_pt, best_tseg, | |
176 | &tseg1, &tseg2); | |
177 | ||
178 | v64 = (u64)best_brp * 1000000000UL; | |
179 | do_div(v64, priv->clock.freq); | |
180 | bt->tq = (u32)v64; | |
181 | bt->prop_seg = tseg1 / 2; | |
182 | bt->phase_seg1 = tseg1 - bt->prop_seg; | |
183 | bt->phase_seg2 = tseg2; | |
2e114374 OH |
184 | |
185 | /* check for sjw user settings */ | |
186 | if (!bt->sjw || !btc->sjw_max) | |
187 | bt->sjw = 1; | |
188 | else { | |
189 | /* bt->sjw is at least 1 -> sanitize upper bound to sjw_max */ | |
190 | if (bt->sjw > btc->sjw_max) | |
191 | bt->sjw = btc->sjw_max; | |
192 | /* bt->sjw must not be higher than tseg2 */ | |
193 | if (tseg2 < bt->sjw) | |
194 | bt->sjw = tseg2; | |
195 | } | |
196 | ||
39549eef WG |
197 | bt->brp = best_brp; |
198 | /* real bit-rate */ | |
199 | bt->bitrate = priv->clock.freq / (bt->brp * (tseg1 + tseg2 + 1)); | |
200 | ||
201 | return 0; | |
202 | } | |
203 | #else /* !CONFIG_CAN_CALC_BITTIMING */ | |
08da7da4 OH |
204 | static int can_calc_bittiming(struct net_device *dev, struct can_bittiming *bt, |
205 | const struct can_bittiming_const *btc) | |
39549eef | 206 | { |
aabdfd6a | 207 | netdev_err(dev, "bit-timing calculation not available\n"); |
39549eef WG |
208 | return -EINVAL; |
209 | } | |
210 | #endif /* CONFIG_CAN_CALC_BITTIMING */ | |
211 | ||
212 | /* | |
213 | * Checks the validity of the specified bit-timing parameters prop_seg, | |
214 | * phase_seg1, phase_seg2 and sjw and tries to determine the bitrate | |
215 | * prescaler value brp. You can find more information in the header | |
216 | * file linux/can/netlink.h. | |
217 | */ | |
08da7da4 OH |
218 | static int can_fixup_bittiming(struct net_device *dev, struct can_bittiming *bt, |
219 | const struct can_bittiming_const *btc) | |
39549eef WG |
220 | { |
221 | struct can_priv *priv = netdev_priv(dev); | |
39549eef WG |
222 | int tseg1, alltseg; |
223 | u64 brp64; | |
224 | ||
39549eef WG |
225 | tseg1 = bt->prop_seg + bt->phase_seg1; |
226 | if (!bt->sjw) | |
227 | bt->sjw = 1; | |
228 | if (bt->sjw > btc->sjw_max || | |
229 | tseg1 < btc->tseg1_min || tseg1 > btc->tseg1_max || | |
230 | bt->phase_seg2 < btc->tseg2_min || bt->phase_seg2 > btc->tseg2_max) | |
231 | return -ERANGE; | |
232 | ||
233 | brp64 = (u64)priv->clock.freq * (u64)bt->tq; | |
234 | if (btc->brp_inc > 1) | |
235 | do_div(brp64, btc->brp_inc); | |
236 | brp64 += 500000000UL - 1; | |
237 | do_div(brp64, 1000000000UL); /* the practicable BRP */ | |
238 | if (btc->brp_inc > 1) | |
239 | brp64 *= btc->brp_inc; | |
240 | bt->brp = (u32)brp64; | |
241 | ||
242 | if (bt->brp < btc->brp_min || bt->brp > btc->brp_max) | |
243 | return -EINVAL; | |
244 | ||
245 | alltseg = bt->prop_seg + bt->phase_seg1 + bt->phase_seg2 + 1; | |
246 | bt->bitrate = priv->clock.freq / (bt->brp * alltseg); | |
247 | bt->sample_point = ((tseg1 + 1) * 1000) / alltseg; | |
248 | ||
249 | return 0; | |
250 | } | |
251 | ||
08da7da4 OH |
252 | static int can_get_bittiming(struct net_device *dev, struct can_bittiming *bt, |
253 | const struct can_bittiming_const *btc) | |
39549eef | 254 | { |
39549eef WG |
255 | int err; |
256 | ||
257 | /* Check if the CAN device has bit-timing parameters */ | |
08da7da4 | 258 | if (!btc) |
d4824432 | 259 | return -EOPNOTSUPP; |
39549eef | 260 | |
d5298dff OH |
261 | /* |
262 | * Depending on the given can_bittiming parameter structure the CAN | |
263 | * timing parameters are calculated based on the provided bitrate OR | |
264 | * alternatively the CAN timing parameters (tq, prop_seg, etc.) are | |
265 | * provided directly which are then checked and fixed up. | |
266 | */ | |
267 | if (!bt->tq && bt->bitrate) | |
08da7da4 | 268 | err = can_calc_bittiming(dev, bt, btc); |
d5298dff | 269 | else if (bt->tq && !bt->bitrate) |
08da7da4 | 270 | err = can_fixup_bittiming(dev, bt, btc); |
d5298dff OH |
271 | else |
272 | err = -EINVAL; | |
39549eef | 273 | |
d5298dff | 274 | return err; |
39549eef WG |
275 | } |
276 | ||
277 | /* | |
278 | * Local echo of CAN messages | |
279 | * | |
280 | * CAN network devices *should* support a local echo functionality | |
281 | * (see Documentation/networking/can.txt). To test the handling of CAN | |
282 | * interfaces that do not support the local echo both driver types are | |
283 | * implemented. In the case that the driver does not support the echo | |
284 | * the IFF_ECHO remains clear in dev->flags. This causes the PF_CAN core | |
285 | * to perform the echo as a fallback solution. | |
286 | */ | |
287 | static void can_flush_echo_skb(struct net_device *dev) | |
288 | { | |
289 | struct can_priv *priv = netdev_priv(dev); | |
290 | struct net_device_stats *stats = &dev->stats; | |
291 | int i; | |
292 | ||
a6e4bc53 | 293 | for (i = 0; i < priv->echo_skb_max; i++) { |
39549eef WG |
294 | if (priv->echo_skb[i]) { |
295 | kfree_skb(priv->echo_skb[i]); | |
296 | priv->echo_skb[i] = NULL; | |
297 | stats->tx_dropped++; | |
298 | stats->tx_aborted_errors++; | |
299 | } | |
300 | } | |
301 | } | |
302 | ||
303 | /* | |
304 | * Put the skb on the stack to be looped backed locally lateron | |
305 | * | |
306 | * The function is typically called in the start_xmit function | |
307 | * of the device driver. The driver must protect access to | |
308 | * priv->echo_skb, if necessary. | |
309 | */ | |
a6e4bc53 WG |
310 | void can_put_echo_skb(struct sk_buff *skb, struct net_device *dev, |
311 | unsigned int idx) | |
39549eef WG |
312 | { |
313 | struct can_priv *priv = netdev_priv(dev); | |
314 | ||
a6e4bc53 WG |
315 | BUG_ON(idx >= priv->echo_skb_max); |
316 | ||
39549eef | 317 | /* check flag whether this packet has to be looped back */ |
a94bc9c4 OH |
318 | if (!(dev->flags & IFF_ECHO) || skb->pkt_type != PACKET_LOOPBACK || |
319 | (skb->protocol != htons(ETH_P_CAN) && | |
320 | skb->protocol != htons(ETH_P_CANFD))) { | |
39549eef WG |
321 | kfree_skb(skb); |
322 | return; | |
323 | } | |
324 | ||
325 | if (!priv->echo_skb[idx]) { | |
39549eef | 326 | |
0ae89beb OH |
327 | skb = can_create_echo_skb(skb); |
328 | if (!skb) | |
329 | return; | |
39549eef WG |
330 | |
331 | /* make settings for echo to reduce code in irq context */ | |
39549eef WG |
332 | skb->pkt_type = PACKET_BROADCAST; |
333 | skb->ip_summed = CHECKSUM_UNNECESSARY; | |
334 | skb->dev = dev; | |
335 | ||
336 | /* save this skb for tx interrupt echo handling */ | |
337 | priv->echo_skb[idx] = skb; | |
338 | } else { | |
339 | /* locking problem with netif_stop_queue() ?? */ | |
aabdfd6a | 340 | netdev_err(dev, "%s: BUG! echo_skb is occupied!\n", __func__); |
39549eef WG |
341 | kfree_skb(skb); |
342 | } | |
343 | } | |
344 | EXPORT_SYMBOL_GPL(can_put_echo_skb); | |
345 | ||
346 | /* | |
347 | * Get the skb from the stack and loop it back locally | |
348 | * | |
349 | * The function is typically called when the TX done interrupt | |
350 | * is handled in the device driver. The driver must protect | |
351 | * access to priv->echo_skb, if necessary. | |
352 | */ | |
cf5046b3 | 353 | unsigned int can_get_echo_skb(struct net_device *dev, unsigned int idx) |
39549eef WG |
354 | { |
355 | struct can_priv *priv = netdev_priv(dev); | |
356 | ||
a6e4bc53 WG |
357 | BUG_ON(idx >= priv->echo_skb_max); |
358 | ||
39e3ab6f | 359 | if (priv->echo_skb[idx]) { |
cf5046b3 MKB |
360 | struct sk_buff *skb = priv->echo_skb[idx]; |
361 | struct can_frame *cf = (struct can_frame *)skb->data; | |
362 | u8 dlc = cf->can_dlc; | |
363 | ||
39549eef WG |
364 | netif_rx(priv->echo_skb[idx]); |
365 | priv->echo_skb[idx] = NULL; | |
cf5046b3 MKB |
366 | |
367 | return dlc; | |
39549eef | 368 | } |
cf5046b3 MKB |
369 | |
370 | return 0; | |
39549eef WG |
371 | } |
372 | EXPORT_SYMBOL_GPL(can_get_echo_skb); | |
373 | ||
39e3ab6f WG |
374 | /* |
375 | * Remove the skb from the stack and free it. | |
376 | * | |
377 | * The function is typically called when TX failed. | |
378 | */ | |
a6e4bc53 | 379 | void can_free_echo_skb(struct net_device *dev, unsigned int idx) |
39e3ab6f WG |
380 | { |
381 | struct can_priv *priv = netdev_priv(dev); | |
382 | ||
a6e4bc53 WG |
383 | BUG_ON(idx >= priv->echo_skb_max); |
384 | ||
39e3ab6f WG |
385 | if (priv->echo_skb[idx]) { |
386 | kfree_skb(priv->echo_skb[idx]); | |
387 | priv->echo_skb[idx] = NULL; | |
388 | } | |
389 | } | |
390 | EXPORT_SYMBOL_GPL(can_free_echo_skb); | |
391 | ||
39549eef WG |
392 | /* |
393 | * CAN device restart for bus-off recovery | |
394 | */ | |
77fc95a3 | 395 | static void can_restart(unsigned long data) |
39549eef WG |
396 | { |
397 | struct net_device *dev = (struct net_device *)data; | |
398 | struct can_priv *priv = netdev_priv(dev); | |
399 | struct net_device_stats *stats = &dev->stats; | |
400 | struct sk_buff *skb; | |
401 | struct can_frame *cf; | |
402 | int err; | |
403 | ||
404 | BUG_ON(netif_carrier_ok(dev)); | |
405 | ||
406 | /* | |
407 | * No synchronization needed because the device is bus-off and | |
408 | * no messages can come in or go out. | |
409 | */ | |
410 | can_flush_echo_skb(dev); | |
411 | ||
412 | /* send restart message upstream */ | |
7b6856a0 | 413 | skb = alloc_can_err_skb(dev, &cf); |
39549eef WG |
414 | if (skb == NULL) { |
415 | err = -ENOMEM; | |
b3d0df7c | 416 | goto restart; |
39549eef | 417 | } |
7b6856a0 | 418 | cf->can_id |= CAN_ERR_RESTARTED; |
39549eef WG |
419 | |
420 | netif_rx(skb); | |
421 | ||
39549eef WG |
422 | stats->rx_packets++; |
423 | stats->rx_bytes += cf->can_dlc; | |
424 | ||
b3d0df7c | 425 | restart: |
aabdfd6a | 426 | netdev_dbg(dev, "restarted\n"); |
39549eef WG |
427 | priv->can_stats.restarts++; |
428 | ||
429 | /* Now restart the device */ | |
430 | err = priv->do_set_mode(dev, CAN_MODE_START); | |
431 | ||
39549eef WG |
432 | netif_carrier_on(dev); |
433 | if (err) | |
aabdfd6a | 434 | netdev_err(dev, "Error %d during restart", err); |
39549eef WG |
435 | } |
436 | ||
437 | int can_restart_now(struct net_device *dev) | |
438 | { | |
439 | struct can_priv *priv = netdev_priv(dev); | |
440 | ||
441 | /* | |
442 | * A manual restart is only permitted if automatic restart is | |
443 | * disabled and the device is in the bus-off state | |
444 | */ | |
445 | if (priv->restart_ms) | |
446 | return -EINVAL; | |
447 | if (priv->state != CAN_STATE_BUS_OFF) | |
448 | return -EBUSY; | |
449 | ||
450 | /* Runs as soon as possible in the timer context */ | |
451 | mod_timer(&priv->restart_timer, jiffies); | |
452 | ||
453 | return 0; | |
454 | } | |
455 | ||
456 | /* | |
457 | * CAN bus-off | |
458 | * | |
459 | * This functions should be called when the device goes bus-off to | |
460 | * tell the netif layer that no more packets can be sent or received. | |
461 | * If enabled, a timer is started to trigger bus-off recovery. | |
462 | */ | |
463 | void can_bus_off(struct net_device *dev) | |
464 | { | |
465 | struct can_priv *priv = netdev_priv(dev); | |
466 | ||
aabdfd6a | 467 | netdev_dbg(dev, "bus-off\n"); |
39549eef WG |
468 | |
469 | netif_carrier_off(dev); | |
470 | priv->can_stats.bus_off++; | |
471 | ||
472 | if (priv->restart_ms) | |
473 | mod_timer(&priv->restart_timer, | |
474 | jiffies + (priv->restart_ms * HZ) / 1000); | |
475 | } | |
476 | EXPORT_SYMBOL_GPL(can_bus_off); | |
477 | ||
478 | static void can_setup(struct net_device *dev) | |
479 | { | |
480 | dev->type = ARPHRD_CAN; | |
1e0625fa | 481 | dev->mtu = CAN_MTU; |
39549eef WG |
482 | dev->hard_header_len = 0; |
483 | dev->addr_len = 0; | |
484 | dev->tx_queue_len = 10; | |
485 | ||
486 | /* New-style flags. */ | |
487 | dev->flags = IFF_NOARP; | |
34324dc2 | 488 | dev->features = NETIF_F_HW_CSUM; |
39549eef WG |
489 | } |
490 | ||
7b6856a0 WG |
491 | struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf) |
492 | { | |
493 | struct sk_buff *skb; | |
494 | ||
156c2bb9 OH |
495 | skb = netdev_alloc_skb(dev, sizeof(struct can_skb_priv) + |
496 | sizeof(struct can_frame)); | |
7b6856a0 WG |
497 | if (unlikely(!skb)) |
498 | return NULL; | |
499 | ||
500 | skb->protocol = htons(ETH_P_CAN); | |
501 | skb->pkt_type = PACKET_BROADCAST; | |
502 | skb->ip_summed = CHECKSUM_UNNECESSARY; | |
156c2bb9 | 503 | |
2bf3440d OH |
504 | can_skb_reserve(skb); |
505 | can_skb_prv(skb)->ifindex = dev->ifindex; | |
156c2bb9 | 506 | |
7b6856a0 WG |
507 | *cf = (struct can_frame *)skb_put(skb, sizeof(struct can_frame)); |
508 | memset(*cf, 0, sizeof(struct can_frame)); | |
509 | ||
510 | return skb; | |
511 | } | |
512 | EXPORT_SYMBOL_GPL(alloc_can_skb); | |
513 | ||
cb2518ca SG |
514 | struct sk_buff *alloc_canfd_skb(struct net_device *dev, |
515 | struct canfd_frame **cfd) | |
516 | { | |
517 | struct sk_buff *skb; | |
518 | ||
519 | skb = netdev_alloc_skb(dev, sizeof(struct can_skb_priv) + | |
520 | sizeof(struct canfd_frame)); | |
521 | if (unlikely(!skb)) | |
522 | return NULL; | |
523 | ||
524 | skb->protocol = htons(ETH_P_CANFD); | |
525 | skb->pkt_type = PACKET_BROADCAST; | |
526 | skb->ip_summed = CHECKSUM_UNNECESSARY; | |
527 | ||
528 | can_skb_reserve(skb); | |
529 | can_skb_prv(skb)->ifindex = dev->ifindex; | |
530 | ||
531 | *cfd = (struct canfd_frame *)skb_put(skb, sizeof(struct canfd_frame)); | |
532 | memset(*cfd, 0, sizeof(struct canfd_frame)); | |
533 | ||
534 | return skb; | |
535 | } | |
536 | EXPORT_SYMBOL_GPL(alloc_canfd_skb); | |
537 | ||
7b6856a0 WG |
538 | struct sk_buff *alloc_can_err_skb(struct net_device *dev, struct can_frame **cf) |
539 | { | |
540 | struct sk_buff *skb; | |
541 | ||
542 | skb = alloc_can_skb(dev, cf); | |
543 | if (unlikely(!skb)) | |
544 | return NULL; | |
545 | ||
546 | (*cf)->can_id = CAN_ERR_FLAG; | |
547 | (*cf)->can_dlc = CAN_ERR_DLC; | |
548 | ||
549 | return skb; | |
550 | } | |
551 | EXPORT_SYMBOL_GPL(alloc_can_err_skb); | |
552 | ||
39549eef WG |
553 | /* |
554 | * Allocate and setup space for the CAN network device | |
555 | */ | |
a6e4bc53 | 556 | struct net_device *alloc_candev(int sizeof_priv, unsigned int echo_skb_max) |
39549eef WG |
557 | { |
558 | struct net_device *dev; | |
559 | struct can_priv *priv; | |
a6e4bc53 | 560 | int size; |
39549eef | 561 | |
a6e4bc53 WG |
562 | if (echo_skb_max) |
563 | size = ALIGN(sizeof_priv, sizeof(struct sk_buff *)) + | |
564 | echo_skb_max * sizeof(struct sk_buff *); | |
565 | else | |
566 | size = sizeof_priv; | |
567 | ||
c835a677 | 568 | dev = alloc_netdev(size, "can%d", NET_NAME_UNKNOWN, can_setup); |
39549eef WG |
569 | if (!dev) |
570 | return NULL; | |
571 | ||
572 | priv = netdev_priv(dev); | |
573 | ||
a6e4bc53 WG |
574 | if (echo_skb_max) { |
575 | priv->echo_skb_max = echo_skb_max; | |
576 | priv->echo_skb = (void *)priv + | |
577 | ALIGN(sizeof_priv, sizeof(struct sk_buff *)); | |
578 | } | |
579 | ||
39549eef WG |
580 | priv->state = CAN_STATE_STOPPED; |
581 | ||
582 | init_timer(&priv->restart_timer); | |
583 | ||
584 | return dev; | |
585 | } | |
586 | EXPORT_SYMBOL_GPL(alloc_candev); | |
587 | ||
588 | /* | |
589 | * Free space of the CAN network device | |
590 | */ | |
591 | void free_candev(struct net_device *dev) | |
592 | { | |
593 | free_netdev(dev); | |
594 | } | |
595 | EXPORT_SYMBOL_GPL(free_candev); | |
596 | ||
bc05a894 OH |
597 | /* |
598 | * changing MTU and control mode for CAN/CANFD devices | |
599 | */ | |
600 | int can_change_mtu(struct net_device *dev, int new_mtu) | |
601 | { | |
602 | struct can_priv *priv = netdev_priv(dev); | |
603 | ||
604 | /* Do not allow changing the MTU while running */ | |
605 | if (dev->flags & IFF_UP) | |
606 | return -EBUSY; | |
607 | ||
608 | /* allow change of MTU according to the CANFD ability of the device */ | |
609 | switch (new_mtu) { | |
610 | case CAN_MTU: | |
611 | priv->ctrlmode &= ~CAN_CTRLMODE_FD; | |
612 | break; | |
613 | ||
614 | case CANFD_MTU: | |
615 | if (!(priv->ctrlmode_supported & CAN_CTRLMODE_FD)) | |
616 | return -EINVAL; | |
617 | ||
618 | priv->ctrlmode |= CAN_CTRLMODE_FD; | |
619 | break; | |
620 | ||
621 | default: | |
622 | return -EINVAL; | |
623 | } | |
624 | ||
625 | dev->mtu = new_mtu; | |
626 | return 0; | |
627 | } | |
628 | EXPORT_SYMBOL_GPL(can_change_mtu); | |
629 | ||
39549eef WG |
630 | /* |
631 | * Common open function when the device gets opened. | |
632 | * | |
633 | * This function should be called in the open function of the device | |
634 | * driver. | |
635 | */ | |
636 | int open_candev(struct net_device *dev) | |
637 | { | |
638 | struct can_priv *priv = netdev_priv(dev); | |
639 | ||
b30749fd | 640 | if (!priv->bittiming.bitrate) { |
aabdfd6a | 641 | netdev_err(dev, "bit-timing not yet defined\n"); |
39549eef WG |
642 | return -EINVAL; |
643 | } | |
644 | ||
dd22586d OH |
645 | /* For CAN FD the data bitrate has to be >= the arbitration bitrate */ |
646 | if ((priv->ctrlmode & CAN_CTRLMODE_FD) && | |
647 | (!priv->data_bittiming.bitrate || | |
648 | (priv->data_bittiming.bitrate < priv->bittiming.bitrate))) { | |
649 | netdev_err(dev, "incorrect/missing data bit-timing\n"); | |
650 | return -EINVAL; | |
651 | } | |
652 | ||
1b0d9224 WG |
653 | /* Switch carrier on if device was stopped while in bus-off state */ |
654 | if (!netif_carrier_ok(dev)) | |
655 | netif_carrier_on(dev); | |
656 | ||
39549eef WG |
657 | setup_timer(&priv->restart_timer, can_restart, (unsigned long)dev); |
658 | ||
659 | return 0; | |
660 | } | |
128ced8f | 661 | EXPORT_SYMBOL_GPL(open_candev); |
39549eef WG |
662 | |
663 | /* | |
664 | * Common close function for cleanup before the device gets closed. | |
665 | * | |
666 | * This function should be called in the close function of the device | |
667 | * driver. | |
668 | */ | |
669 | void close_candev(struct net_device *dev) | |
670 | { | |
671 | struct can_priv *priv = netdev_priv(dev); | |
672 | ||
ab48b03e | 673 | del_timer_sync(&priv->restart_timer); |
39549eef WG |
674 | can_flush_echo_skb(dev); |
675 | } | |
676 | EXPORT_SYMBOL_GPL(close_candev); | |
677 | ||
678 | /* | |
679 | * CAN netlink interface | |
680 | */ | |
681 | static const struct nla_policy can_policy[IFLA_CAN_MAX + 1] = { | |
682 | [IFLA_CAN_STATE] = { .type = NLA_U32 }, | |
683 | [IFLA_CAN_CTRLMODE] = { .len = sizeof(struct can_ctrlmode) }, | |
684 | [IFLA_CAN_RESTART_MS] = { .type = NLA_U32 }, | |
685 | [IFLA_CAN_RESTART] = { .type = NLA_U32 }, | |
686 | [IFLA_CAN_BITTIMING] = { .len = sizeof(struct can_bittiming) }, | |
687 | [IFLA_CAN_BITTIMING_CONST] | |
688 | = { .len = sizeof(struct can_bittiming_const) }, | |
689 | [IFLA_CAN_CLOCK] = { .len = sizeof(struct can_clock) }, | |
52c793f2 | 690 | [IFLA_CAN_BERR_COUNTER] = { .len = sizeof(struct can_berr_counter) }, |
9859ccd2 OH |
691 | [IFLA_CAN_DATA_BITTIMING] |
692 | = { .len = sizeof(struct can_bittiming) }, | |
693 | [IFLA_CAN_DATA_BITTIMING_CONST] | |
694 | = { .len = sizeof(struct can_bittiming_const) }, | |
39549eef WG |
695 | }; |
696 | ||
697 | static int can_changelink(struct net_device *dev, | |
698 | struct nlattr *tb[], struct nlattr *data[]) | |
699 | { | |
700 | struct can_priv *priv = netdev_priv(dev); | |
701 | int err; | |
702 | ||
703 | /* We need synchronization with dev->stop() */ | |
704 | ASSERT_RTNL(); | |
705 | ||
39549eef WG |
706 | if (data[IFLA_CAN_BITTIMING]) { |
707 | struct can_bittiming bt; | |
708 | ||
709 | /* Do not allow changing bittiming while running */ | |
710 | if (dev->flags & IFF_UP) | |
711 | return -EBUSY; | |
712 | memcpy(&bt, nla_data(data[IFLA_CAN_BITTIMING]), sizeof(bt)); | |
08da7da4 | 713 | err = can_get_bittiming(dev, &bt, priv->bittiming_const); |
39549eef WG |
714 | if (err) |
715 | return err; | |
716 | memcpy(&priv->bittiming, &bt, sizeof(bt)); | |
717 | ||
718 | if (priv->do_set_bittiming) { | |
719 | /* Finally, set the bit-timing registers */ | |
720 | err = priv->do_set_bittiming(dev); | |
721 | if (err) | |
722 | return err; | |
723 | } | |
724 | } | |
725 | ||
49cb5c0e MKB |
726 | if (data[IFLA_CAN_CTRLMODE]) { |
727 | struct can_ctrlmode *cm; | |
728 | ||
729 | /* Do not allow changing controller mode while running */ | |
730 | if (dev->flags & IFF_UP) | |
731 | return -EBUSY; | |
732 | cm = nla_data(data[IFLA_CAN_CTRLMODE]); | |
733 | if (cm->flags & ~priv->ctrlmode_supported) | |
734 | return -EOPNOTSUPP; | |
735 | priv->ctrlmode &= ~cm->mask; | |
736 | priv->ctrlmode |= cm->flags; | |
bc05a894 OH |
737 | |
738 | /* CAN_CTRLMODE_FD can only be set when driver supports FD */ | |
739 | if (priv->ctrlmode & CAN_CTRLMODE_FD) | |
740 | dev->mtu = CANFD_MTU; | |
741 | else | |
742 | dev->mtu = CAN_MTU; | |
49cb5c0e MKB |
743 | } |
744 | ||
39549eef WG |
745 | if (data[IFLA_CAN_RESTART_MS]) { |
746 | /* Do not allow changing restart delay while running */ | |
747 | if (dev->flags & IFF_UP) | |
748 | return -EBUSY; | |
749 | priv->restart_ms = nla_get_u32(data[IFLA_CAN_RESTART_MS]); | |
750 | } | |
751 | ||
752 | if (data[IFLA_CAN_RESTART]) { | |
753 | /* Do not allow a restart while not running */ | |
754 | if (!(dev->flags & IFF_UP)) | |
755 | return -EINVAL; | |
756 | err = can_restart_now(dev); | |
757 | if (err) | |
758 | return err; | |
759 | } | |
760 | ||
9859ccd2 OH |
761 | if (data[IFLA_CAN_DATA_BITTIMING]) { |
762 | struct can_bittiming dbt; | |
763 | ||
764 | /* Do not allow changing bittiming while running */ | |
765 | if (dev->flags & IFF_UP) | |
766 | return -EBUSY; | |
767 | memcpy(&dbt, nla_data(data[IFLA_CAN_DATA_BITTIMING]), | |
768 | sizeof(dbt)); | |
769 | err = can_get_bittiming(dev, &dbt, priv->data_bittiming_const); | |
770 | if (err) | |
771 | return err; | |
772 | memcpy(&priv->data_bittiming, &dbt, sizeof(dbt)); | |
773 | ||
774 | if (priv->do_set_data_bittiming) { | |
775 | /* Finally, set the bit-timing registers */ | |
776 | err = priv->do_set_data_bittiming(dev); | |
777 | if (err) | |
778 | return err; | |
779 | } | |
780 | } | |
781 | ||
39549eef WG |
782 | return 0; |
783 | } | |
784 | ||
53a0ef86 WG |
785 | static size_t can_get_size(const struct net_device *dev) |
786 | { | |
787 | struct can_priv *priv = netdev_priv(dev); | |
c13c64d8 MKB |
788 | size_t size = 0; |
789 | ||
b30749fd OH |
790 | if (priv->bittiming.bitrate) /* IFLA_CAN_BITTIMING */ |
791 | size += nla_total_size(sizeof(struct can_bittiming)); | |
c13c64d8 | 792 | if (priv->bittiming_const) /* IFLA_CAN_BITTIMING_CONST */ |
fe119a05 | 793 | size += nla_total_size(sizeof(struct can_bittiming_const)); |
c13c64d8 MKB |
794 | size += nla_total_size(sizeof(struct can_clock)); /* IFLA_CAN_CLOCK */ |
795 | size += nla_total_size(sizeof(u32)); /* IFLA_CAN_STATE */ | |
796 | size += nla_total_size(sizeof(struct can_ctrlmode)); /* IFLA_CAN_CTRLMODE */ | |
797 | size += nla_total_size(sizeof(u32)); /* IFLA_CAN_RESTART_MS */ | |
798 | if (priv->do_get_berr_counter) /* IFLA_CAN_BERR_COUNTER */ | |
799 | size += nla_total_size(sizeof(struct can_berr_counter)); | |
9859ccd2 OH |
800 | if (priv->data_bittiming.bitrate) /* IFLA_CAN_DATA_BITTIMING */ |
801 | size += nla_total_size(sizeof(struct can_bittiming)); | |
802 | if (priv->data_bittiming_const) /* IFLA_CAN_DATA_BITTIMING_CONST */ | |
803 | size += nla_total_size(sizeof(struct can_bittiming_const)); | |
53a0ef86 WG |
804 | |
805 | return size; | |
806 | } | |
807 | ||
39549eef WG |
808 | static int can_fill_info(struct sk_buff *skb, const struct net_device *dev) |
809 | { | |
810 | struct can_priv *priv = netdev_priv(dev); | |
811 | struct can_ctrlmode cm = {.flags = priv->ctrlmode}; | |
52c793f2 | 812 | struct can_berr_counter bec; |
39549eef WG |
813 | enum can_state state = priv->state; |
814 | ||
815 | if (priv->do_get_state) | |
816 | priv->do_get_state(dev, &state); | |
9859ccd2 | 817 | |
b30749fd OH |
818 | if ((priv->bittiming.bitrate && |
819 | nla_put(skb, IFLA_CAN_BITTIMING, | |
820 | sizeof(priv->bittiming), &priv->bittiming)) || | |
9859ccd2 | 821 | |
57a59b9e MKB |
822 | (priv->bittiming_const && |
823 | nla_put(skb, IFLA_CAN_BITTIMING_CONST, | |
824 | sizeof(*priv->bittiming_const), priv->bittiming_const)) || | |
9859ccd2 | 825 | |
31e0e328 | 826 | nla_put(skb, IFLA_CAN_CLOCK, sizeof(cm), &priv->clock) || |
57a59b9e MKB |
827 | nla_put_u32(skb, IFLA_CAN_STATE, state) || |
828 | nla_put(skb, IFLA_CAN_CTRLMODE, sizeof(cm), &cm) || | |
829 | nla_put_u32(skb, IFLA_CAN_RESTART_MS, priv->restart_ms) || | |
9859ccd2 | 830 | |
31e0e328 DM |
831 | (priv->do_get_berr_counter && |
832 | !priv->do_get_berr_counter(dev, &bec) && | |
9859ccd2 OH |
833 | nla_put(skb, IFLA_CAN_BERR_COUNTER, sizeof(bec), &bec)) || |
834 | ||
835 | (priv->data_bittiming.bitrate && | |
836 | nla_put(skb, IFLA_CAN_DATA_BITTIMING, | |
837 | sizeof(priv->data_bittiming), &priv->data_bittiming)) || | |
838 | ||
839 | (priv->data_bittiming_const && | |
840 | nla_put(skb, IFLA_CAN_DATA_BITTIMING_CONST, | |
841 | sizeof(*priv->data_bittiming_const), | |
842 | priv->data_bittiming_const))) | |
57a59b9e | 843 | return -EMSGSIZE; |
9859ccd2 | 844 | |
39549eef | 845 | return 0; |
39549eef WG |
846 | } |
847 | ||
55369c0a WG |
848 | static size_t can_get_xstats_size(const struct net_device *dev) |
849 | { | |
850 | return sizeof(struct can_device_stats); | |
851 | } | |
852 | ||
39549eef WG |
853 | static int can_fill_xstats(struct sk_buff *skb, const struct net_device *dev) |
854 | { | |
855 | struct can_priv *priv = netdev_priv(dev); | |
856 | ||
31e0e328 DM |
857 | if (nla_put(skb, IFLA_INFO_XSTATS, |
858 | sizeof(priv->can_stats), &priv->can_stats)) | |
859 | goto nla_put_failure; | |
39549eef WG |
860 | return 0; |
861 | ||
862 | nla_put_failure: | |
863 | return -EMSGSIZE; | |
864 | } | |
865 | ||
81adee47 | 866 | static int can_newlink(struct net *src_net, struct net_device *dev, |
993e6f2f OH |
867 | struct nlattr *tb[], struct nlattr *data[]) |
868 | { | |
869 | return -EOPNOTSUPP; | |
870 | } | |
871 | ||
39549eef WG |
872 | static struct rtnl_link_ops can_link_ops __read_mostly = { |
873 | .kind = "can", | |
874 | .maxtype = IFLA_CAN_MAX, | |
875 | .policy = can_policy, | |
876 | .setup = can_setup, | |
993e6f2f | 877 | .newlink = can_newlink, |
39549eef | 878 | .changelink = can_changelink, |
53a0ef86 | 879 | .get_size = can_get_size, |
39549eef | 880 | .fill_info = can_fill_info, |
55369c0a | 881 | .get_xstats_size = can_get_xstats_size, |
39549eef WG |
882 | .fill_xstats = can_fill_xstats, |
883 | }; | |
884 | ||
885 | /* | |
886 | * Register the CAN network device | |
887 | */ | |
888 | int register_candev(struct net_device *dev) | |
889 | { | |
890 | dev->rtnl_link_ops = &can_link_ops; | |
891 | return register_netdev(dev); | |
892 | } | |
893 | EXPORT_SYMBOL_GPL(register_candev); | |
894 | ||
895 | /* | |
896 | * Unregister the CAN network device | |
897 | */ | |
898 | void unregister_candev(struct net_device *dev) | |
899 | { | |
900 | unregister_netdev(dev); | |
901 | } | |
902 | EXPORT_SYMBOL_GPL(unregister_candev); | |
903 | ||
bf03a537 KVD |
904 | /* |
905 | * Test if a network device is a candev based device | |
906 | * and return the can_priv* if so. | |
907 | */ | |
908 | struct can_priv *safe_candev_priv(struct net_device *dev) | |
909 | { | |
910 | if ((dev->type != ARPHRD_CAN) || (dev->rtnl_link_ops != &can_link_ops)) | |
911 | return NULL; | |
912 | ||
913 | return netdev_priv(dev); | |
914 | } | |
915 | EXPORT_SYMBOL_GPL(safe_candev_priv); | |
916 | ||
39549eef WG |
917 | static __init int can_dev_init(void) |
918 | { | |
919 | int err; | |
920 | ||
a1ef7bd9 KVD |
921 | can_led_notifier_init(); |
922 | ||
39549eef WG |
923 | err = rtnl_link_register(&can_link_ops); |
924 | if (!err) | |
925 | printk(KERN_INFO MOD_DESC "\n"); | |
926 | ||
927 | return err; | |
928 | } | |
929 | module_init(can_dev_init); | |
930 | ||
931 | static __exit void can_dev_exit(void) | |
932 | { | |
933 | rtnl_link_unregister(&can_link_ops); | |
a1ef7bd9 KVD |
934 | |
935 | can_led_notifier_exit(); | |
39549eef WG |
936 | } |
937 | module_exit(can_dev_exit); | |
938 | ||
939 | MODULE_ALIAS_RTNL_LINK("can"); |