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![Lad, Prabhakar](/assets/img/avatar_default.png)
this patch removes best_rate variable from can_calc_bittiming() function which was set but was never used. Signed-off-by: Lad, Prabhakar <prabhakar.csengg@gmail.com> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
938 lines
24 KiB
C
938 lines
24 KiB
C
/*
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* Copyright (C) 2005 Marc Kleine-Budde, Pengutronix
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* Copyright (C) 2006 Andrey Volkov, Varma Electronics
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* Copyright (C) 2008-2009 Wolfgang Grandegger <wg@grandegger.com>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the version 2 of the GNU General Public License
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* as published by the Free Software Foundation
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, see <http://www.gnu.org/licenses/>.
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*/
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#include <linux/module.h>
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#include <linux/kernel.h>
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#include <linux/slab.h>
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#include <linux/netdevice.h>
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#include <linux/if_arp.h>
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#include <linux/can.h>
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#include <linux/can/dev.h>
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#include <linux/can/skb.h>
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#include <linux/can/netlink.h>
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#include <linux/can/led.h>
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#include <net/rtnetlink.h>
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#define MOD_DESC "CAN device driver interface"
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MODULE_DESCRIPTION(MOD_DESC);
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MODULE_LICENSE("GPL v2");
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MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
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/* CAN DLC to real data length conversion helpers */
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static const u8 dlc2len[] = {0, 1, 2, 3, 4, 5, 6, 7,
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8, 12, 16, 20, 24, 32, 48, 64};
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/* get data length from can_dlc with sanitized can_dlc */
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u8 can_dlc2len(u8 can_dlc)
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{
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return dlc2len[can_dlc & 0x0F];
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}
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EXPORT_SYMBOL_GPL(can_dlc2len);
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static const u8 len2dlc[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, /* 0 - 8 */
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9, 9, 9, 9, /* 9 - 12 */
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10, 10, 10, 10, /* 13 - 16 */
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11, 11, 11, 11, /* 17 - 20 */
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12, 12, 12, 12, /* 21 - 24 */
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13, 13, 13, 13, 13, 13, 13, 13, /* 25 - 32 */
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14, 14, 14, 14, 14, 14, 14, 14, /* 33 - 40 */
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14, 14, 14, 14, 14, 14, 14, 14, /* 41 - 48 */
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15, 15, 15, 15, 15, 15, 15, 15, /* 49 - 56 */
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15, 15, 15, 15, 15, 15, 15, 15}; /* 57 - 64 */
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/* map the sanitized data length to an appropriate data length code */
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u8 can_len2dlc(u8 len)
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{
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if (unlikely(len > 64))
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return 0xF;
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return len2dlc[len];
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}
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EXPORT_SYMBOL_GPL(can_len2dlc);
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#ifdef CONFIG_CAN_CALC_BITTIMING
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#define CAN_CALC_MAX_ERROR 50 /* in one-tenth of a percent */
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/*
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* Bit-timing calculation derived from:
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*
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* Code based on LinCAN sources and H8S2638 project
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* Copyright 2004-2006 Pavel Pisa - DCE FELK CVUT cz
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* Copyright 2005 Stanislav Marek
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* email: pisa@cmp.felk.cvut.cz
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*
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* Calculates proper bit-timing parameters for a specified bit-rate
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* and sample-point, which can then be used to set the bit-timing
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* registers of the CAN controller. You can find more information
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* in the header file linux/can/netlink.h.
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*/
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static int can_update_spt(const struct can_bittiming_const *btc,
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int sampl_pt, int tseg, int *tseg1, int *tseg2)
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{
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*tseg2 = tseg + 1 - (sampl_pt * (tseg + 1)) / 1000;
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if (*tseg2 < btc->tseg2_min)
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*tseg2 = btc->tseg2_min;
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if (*tseg2 > btc->tseg2_max)
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*tseg2 = btc->tseg2_max;
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*tseg1 = tseg - *tseg2;
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if (*tseg1 > btc->tseg1_max) {
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*tseg1 = btc->tseg1_max;
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*tseg2 = tseg - *tseg1;
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}
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return 1000 * (tseg + 1 - *tseg2) / (tseg + 1);
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}
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static int can_calc_bittiming(struct net_device *dev, struct can_bittiming *bt,
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const struct can_bittiming_const *btc)
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{
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struct can_priv *priv = netdev_priv(dev);
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long best_error = 1000000000, error = 0;
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int best_tseg = 0, best_brp = 0, brp = 0;
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int tsegall, tseg = 0, tseg1 = 0, tseg2 = 0;
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int spt_error = 1000, spt = 0, sampl_pt;
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long rate;
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u64 v64;
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/* Use CIA recommended sample points */
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if (bt->sample_point) {
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sampl_pt = bt->sample_point;
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} else {
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if (bt->bitrate > 800000)
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sampl_pt = 750;
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else if (bt->bitrate > 500000)
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sampl_pt = 800;
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else
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sampl_pt = 875;
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}
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/* tseg even = round down, odd = round up */
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for (tseg = (btc->tseg1_max + btc->tseg2_max) * 2 + 1;
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tseg >= (btc->tseg1_min + btc->tseg2_min) * 2; tseg--) {
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tsegall = 1 + tseg / 2;
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/* Compute all possible tseg choices (tseg=tseg1+tseg2) */
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brp = priv->clock.freq / (tsegall * bt->bitrate) + tseg % 2;
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/* chose brp step which is possible in system */
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brp = (brp / btc->brp_inc) * btc->brp_inc;
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if ((brp < btc->brp_min) || (brp > btc->brp_max))
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continue;
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rate = priv->clock.freq / (brp * tsegall);
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error = bt->bitrate - rate;
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/* tseg brp biterror */
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if (error < 0)
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error = -error;
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if (error > best_error)
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continue;
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best_error = error;
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if (error == 0) {
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spt = can_update_spt(btc, sampl_pt, tseg / 2,
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&tseg1, &tseg2);
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error = sampl_pt - spt;
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if (error < 0)
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error = -error;
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if (error > spt_error)
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continue;
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spt_error = error;
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}
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best_tseg = tseg / 2;
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best_brp = brp;
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if (error == 0)
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break;
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}
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if (best_error) {
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/* Error in one-tenth of a percent */
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error = (best_error * 1000) / bt->bitrate;
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if (error > CAN_CALC_MAX_ERROR) {
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netdev_err(dev,
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"bitrate error %ld.%ld%% too high\n",
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error / 10, error % 10);
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return -EDOM;
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} else {
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netdev_warn(dev, "bitrate error %ld.%ld%%\n",
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error / 10, error % 10);
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}
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}
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/* real sample point */
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bt->sample_point = can_update_spt(btc, sampl_pt, best_tseg,
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&tseg1, &tseg2);
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v64 = (u64)best_brp * 1000000000UL;
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do_div(v64, priv->clock.freq);
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bt->tq = (u32)v64;
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bt->prop_seg = tseg1 / 2;
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bt->phase_seg1 = tseg1 - bt->prop_seg;
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bt->phase_seg2 = tseg2;
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/* check for sjw user settings */
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if (!bt->sjw || !btc->sjw_max)
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bt->sjw = 1;
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else {
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/* bt->sjw is at least 1 -> sanitize upper bound to sjw_max */
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if (bt->sjw > btc->sjw_max)
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bt->sjw = btc->sjw_max;
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/* bt->sjw must not be higher than tseg2 */
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if (tseg2 < bt->sjw)
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bt->sjw = tseg2;
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}
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bt->brp = best_brp;
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/* real bit-rate */
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bt->bitrate = priv->clock.freq / (bt->brp * (tseg1 + tseg2 + 1));
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return 0;
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}
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#else /* !CONFIG_CAN_CALC_BITTIMING */
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static int can_calc_bittiming(struct net_device *dev, struct can_bittiming *bt,
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const struct can_bittiming_const *btc)
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{
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netdev_err(dev, "bit-timing calculation not available\n");
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return -EINVAL;
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}
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#endif /* CONFIG_CAN_CALC_BITTIMING */
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/*
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* Checks the validity of the specified bit-timing parameters prop_seg,
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* phase_seg1, phase_seg2 and sjw and tries to determine the bitrate
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* prescaler value brp. You can find more information in the header
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* file linux/can/netlink.h.
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*/
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static int can_fixup_bittiming(struct net_device *dev, struct can_bittiming *bt,
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const struct can_bittiming_const *btc)
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{
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struct can_priv *priv = netdev_priv(dev);
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int tseg1, alltseg;
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u64 brp64;
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tseg1 = bt->prop_seg + bt->phase_seg1;
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if (!bt->sjw)
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bt->sjw = 1;
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if (bt->sjw > btc->sjw_max ||
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tseg1 < btc->tseg1_min || tseg1 > btc->tseg1_max ||
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bt->phase_seg2 < btc->tseg2_min || bt->phase_seg2 > btc->tseg2_max)
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return -ERANGE;
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brp64 = (u64)priv->clock.freq * (u64)bt->tq;
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if (btc->brp_inc > 1)
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do_div(brp64, btc->brp_inc);
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brp64 += 500000000UL - 1;
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do_div(brp64, 1000000000UL); /* the practicable BRP */
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if (btc->brp_inc > 1)
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brp64 *= btc->brp_inc;
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bt->brp = (u32)brp64;
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if (bt->brp < btc->brp_min || bt->brp > btc->brp_max)
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return -EINVAL;
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alltseg = bt->prop_seg + bt->phase_seg1 + bt->phase_seg2 + 1;
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bt->bitrate = priv->clock.freq / (bt->brp * alltseg);
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bt->sample_point = ((tseg1 + 1) * 1000) / alltseg;
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return 0;
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}
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static int can_get_bittiming(struct net_device *dev, struct can_bittiming *bt,
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const struct can_bittiming_const *btc)
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{
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int err;
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/* Check if the CAN device has bit-timing parameters */
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if (!btc)
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return -EOPNOTSUPP;
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/*
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* Depending on the given can_bittiming parameter structure the CAN
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* timing parameters are calculated based on the provided bitrate OR
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* alternatively the CAN timing parameters (tq, prop_seg, etc.) are
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* provided directly which are then checked and fixed up.
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*/
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if (!bt->tq && bt->bitrate)
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err = can_calc_bittiming(dev, bt, btc);
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else if (bt->tq && !bt->bitrate)
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err = can_fixup_bittiming(dev, bt, btc);
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else
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err = -EINVAL;
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return err;
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}
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/*
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* Local echo of CAN messages
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*
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* CAN network devices *should* support a local echo functionality
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* (see Documentation/networking/can.txt). To test the handling of CAN
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* interfaces that do not support the local echo both driver types are
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* implemented. In the case that the driver does not support the echo
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* the IFF_ECHO remains clear in dev->flags. This causes the PF_CAN core
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* to perform the echo as a fallback solution.
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*/
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static void can_flush_echo_skb(struct net_device *dev)
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{
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struct can_priv *priv = netdev_priv(dev);
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struct net_device_stats *stats = &dev->stats;
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int i;
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for (i = 0; i < priv->echo_skb_max; i++) {
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if (priv->echo_skb[i]) {
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kfree_skb(priv->echo_skb[i]);
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priv->echo_skb[i] = NULL;
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stats->tx_dropped++;
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stats->tx_aborted_errors++;
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}
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}
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}
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/*
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* Put the skb on the stack to be looped backed locally lateron
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*
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* The function is typically called in the start_xmit function
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* of the device driver. The driver must protect access to
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* priv->echo_skb, if necessary.
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*/
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void can_put_echo_skb(struct sk_buff *skb, struct net_device *dev,
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unsigned int idx)
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{
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struct can_priv *priv = netdev_priv(dev);
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BUG_ON(idx >= priv->echo_skb_max);
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/* check flag whether this packet has to be looped back */
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if (!(dev->flags & IFF_ECHO) || skb->pkt_type != PACKET_LOOPBACK ||
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(skb->protocol != htons(ETH_P_CAN) &&
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skb->protocol != htons(ETH_P_CANFD))) {
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kfree_skb(skb);
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return;
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}
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if (!priv->echo_skb[idx]) {
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skb = can_create_echo_skb(skb);
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if (!skb)
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return;
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/* make settings for echo to reduce code in irq context */
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skb->pkt_type = PACKET_BROADCAST;
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skb->ip_summed = CHECKSUM_UNNECESSARY;
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skb->dev = dev;
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/* save this skb for tx interrupt echo handling */
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priv->echo_skb[idx] = skb;
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} else {
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/* locking problem with netif_stop_queue() ?? */
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netdev_err(dev, "%s: BUG! echo_skb is occupied!\n", __func__);
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kfree_skb(skb);
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}
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}
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EXPORT_SYMBOL_GPL(can_put_echo_skb);
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/*
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* Get the skb from the stack and loop it back locally
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*
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* The function is typically called when the TX done interrupt
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* is handled in the device driver. The driver must protect
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* access to priv->echo_skb, if necessary.
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*/
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unsigned int can_get_echo_skb(struct net_device *dev, unsigned int idx)
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{
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struct can_priv *priv = netdev_priv(dev);
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BUG_ON(idx >= priv->echo_skb_max);
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if (priv->echo_skb[idx]) {
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struct sk_buff *skb = priv->echo_skb[idx];
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struct can_frame *cf = (struct can_frame *)skb->data;
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u8 dlc = cf->can_dlc;
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netif_rx(priv->echo_skb[idx]);
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priv->echo_skb[idx] = NULL;
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return dlc;
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}
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return 0;
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}
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EXPORT_SYMBOL_GPL(can_get_echo_skb);
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/*
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* Remove the skb from the stack and free it.
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*
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* The function is typically called when TX failed.
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*/
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void can_free_echo_skb(struct net_device *dev, unsigned int idx)
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{
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struct can_priv *priv = netdev_priv(dev);
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BUG_ON(idx >= priv->echo_skb_max);
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if (priv->echo_skb[idx]) {
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kfree_skb(priv->echo_skb[idx]);
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priv->echo_skb[idx] = NULL;
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}
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}
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EXPORT_SYMBOL_GPL(can_free_echo_skb);
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/*
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* CAN device restart for bus-off recovery
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*/
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static void can_restart(unsigned long data)
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{
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struct net_device *dev = (struct net_device *)data;
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struct can_priv *priv = netdev_priv(dev);
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struct net_device_stats *stats = &dev->stats;
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struct sk_buff *skb;
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struct can_frame *cf;
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int err;
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BUG_ON(netif_carrier_ok(dev));
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/*
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* No synchronization needed because the device is bus-off and
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* no messages can come in or go out.
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*/
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can_flush_echo_skb(dev);
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/* send restart message upstream */
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skb = alloc_can_err_skb(dev, &cf);
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if (skb == NULL) {
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err = -ENOMEM;
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goto restart;
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}
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cf->can_id |= CAN_ERR_RESTARTED;
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netif_rx(skb);
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stats->rx_packets++;
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stats->rx_bytes += cf->can_dlc;
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restart:
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netdev_dbg(dev, "restarted\n");
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priv->can_stats.restarts++;
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/* Now restart the device */
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err = priv->do_set_mode(dev, CAN_MODE_START);
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|
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netif_carrier_on(dev);
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if (err)
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netdev_err(dev, "Error %d during restart", err);
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}
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int can_restart_now(struct net_device *dev)
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{
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struct can_priv *priv = netdev_priv(dev);
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|
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/*
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* A manual restart is only permitted if automatic restart is
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* disabled and the device is in the bus-off state
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*/
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if (priv->restart_ms)
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return -EINVAL;
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if (priv->state != CAN_STATE_BUS_OFF)
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return -EBUSY;
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|
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/* Runs as soon as possible in the timer context */
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mod_timer(&priv->restart_timer, jiffies);
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return 0;
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}
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|
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/*
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* CAN bus-off
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*
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* This functions should be called when the device goes bus-off to
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* tell the netif layer that no more packets can be sent or received.
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* If enabled, a timer is started to trigger bus-off recovery.
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*/
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void can_bus_off(struct net_device *dev)
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{
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struct can_priv *priv = netdev_priv(dev);
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netdev_dbg(dev, "bus-off\n");
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netif_carrier_off(dev);
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priv->can_stats.bus_off++;
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if (priv->restart_ms)
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mod_timer(&priv->restart_timer,
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jiffies + (priv->restart_ms * HZ) / 1000);
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}
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EXPORT_SYMBOL_GPL(can_bus_off);
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|
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static void can_setup(struct net_device *dev)
|
|
{
|
|
dev->type = ARPHRD_CAN;
|
|
dev->mtu = CAN_MTU;
|
|
dev->hard_header_len = 0;
|
|
dev->addr_len = 0;
|
|
dev->tx_queue_len = 10;
|
|
|
|
/* New-style flags. */
|
|
dev->flags = IFF_NOARP;
|
|
dev->features = NETIF_F_HW_CSUM;
|
|
}
|
|
|
|
struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf)
|
|
{
|
|
struct sk_buff *skb;
|
|
|
|
skb = netdev_alloc_skb(dev, sizeof(struct can_skb_priv) +
|
|
sizeof(struct can_frame));
|
|
if (unlikely(!skb))
|
|
return NULL;
|
|
|
|
skb->protocol = htons(ETH_P_CAN);
|
|
skb->pkt_type = PACKET_BROADCAST;
|
|
skb->ip_summed = CHECKSUM_UNNECESSARY;
|
|
|
|
can_skb_reserve(skb);
|
|
can_skb_prv(skb)->ifindex = dev->ifindex;
|
|
|
|
*cf = (struct can_frame *)skb_put(skb, sizeof(struct can_frame));
|
|
memset(*cf, 0, sizeof(struct can_frame));
|
|
|
|
return skb;
|
|
}
|
|
EXPORT_SYMBOL_GPL(alloc_can_skb);
|
|
|
|
struct sk_buff *alloc_canfd_skb(struct net_device *dev,
|
|
struct canfd_frame **cfd)
|
|
{
|
|
struct sk_buff *skb;
|
|
|
|
skb = netdev_alloc_skb(dev, sizeof(struct can_skb_priv) +
|
|
sizeof(struct canfd_frame));
|
|
if (unlikely(!skb))
|
|
return NULL;
|
|
|
|
skb->protocol = htons(ETH_P_CANFD);
|
|
skb->pkt_type = PACKET_BROADCAST;
|
|
skb->ip_summed = CHECKSUM_UNNECESSARY;
|
|
|
|
can_skb_reserve(skb);
|
|
can_skb_prv(skb)->ifindex = dev->ifindex;
|
|
|
|
*cfd = (struct canfd_frame *)skb_put(skb, sizeof(struct canfd_frame));
|
|
memset(*cfd, 0, sizeof(struct canfd_frame));
|
|
|
|
return skb;
|
|
}
|
|
EXPORT_SYMBOL_GPL(alloc_canfd_skb);
|
|
|
|
struct sk_buff *alloc_can_err_skb(struct net_device *dev, struct can_frame **cf)
|
|
{
|
|
struct sk_buff *skb;
|
|
|
|
skb = alloc_can_skb(dev, cf);
|
|
if (unlikely(!skb))
|
|
return NULL;
|
|
|
|
(*cf)->can_id = CAN_ERR_FLAG;
|
|
(*cf)->can_dlc = CAN_ERR_DLC;
|
|
|
|
return skb;
|
|
}
|
|
EXPORT_SYMBOL_GPL(alloc_can_err_skb);
|
|
|
|
/*
|
|
* Allocate and setup space for the CAN network device
|
|
*/
|
|
struct net_device *alloc_candev(int sizeof_priv, unsigned int echo_skb_max)
|
|
{
|
|
struct net_device *dev;
|
|
struct can_priv *priv;
|
|
int size;
|
|
|
|
if (echo_skb_max)
|
|
size = ALIGN(sizeof_priv, sizeof(struct sk_buff *)) +
|
|
echo_skb_max * sizeof(struct sk_buff *);
|
|
else
|
|
size = sizeof_priv;
|
|
|
|
dev = alloc_netdev(size, "can%d", NET_NAME_UNKNOWN, can_setup);
|
|
if (!dev)
|
|
return NULL;
|
|
|
|
priv = netdev_priv(dev);
|
|
|
|
if (echo_skb_max) {
|
|
priv->echo_skb_max = echo_skb_max;
|
|
priv->echo_skb = (void *)priv +
|
|
ALIGN(sizeof_priv, sizeof(struct sk_buff *));
|
|
}
|
|
|
|
priv->state = CAN_STATE_STOPPED;
|
|
|
|
init_timer(&priv->restart_timer);
|
|
|
|
return dev;
|
|
}
|
|
EXPORT_SYMBOL_GPL(alloc_candev);
|
|
|
|
/*
|
|
* Free space of the CAN network device
|
|
*/
|
|
void free_candev(struct net_device *dev)
|
|
{
|
|
free_netdev(dev);
|
|
}
|
|
EXPORT_SYMBOL_GPL(free_candev);
|
|
|
|
/*
|
|
* changing MTU and control mode for CAN/CANFD devices
|
|
*/
|
|
int can_change_mtu(struct net_device *dev, int new_mtu)
|
|
{
|
|
struct can_priv *priv = netdev_priv(dev);
|
|
|
|
/* Do not allow changing the MTU while running */
|
|
if (dev->flags & IFF_UP)
|
|
return -EBUSY;
|
|
|
|
/* allow change of MTU according to the CANFD ability of the device */
|
|
switch (new_mtu) {
|
|
case CAN_MTU:
|
|
priv->ctrlmode &= ~CAN_CTRLMODE_FD;
|
|
break;
|
|
|
|
case CANFD_MTU:
|
|
if (!(priv->ctrlmode_supported & CAN_CTRLMODE_FD))
|
|
return -EINVAL;
|
|
|
|
priv->ctrlmode |= CAN_CTRLMODE_FD;
|
|
break;
|
|
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
|
|
dev->mtu = new_mtu;
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(can_change_mtu);
|
|
|
|
/*
|
|
* Common open function when the device gets opened.
|
|
*
|
|
* This function should be called in the open function of the device
|
|
* driver.
|
|
*/
|
|
int open_candev(struct net_device *dev)
|
|
{
|
|
struct can_priv *priv = netdev_priv(dev);
|
|
|
|
if (!priv->bittiming.bitrate) {
|
|
netdev_err(dev, "bit-timing not yet defined\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* For CAN FD the data bitrate has to be >= the arbitration bitrate */
|
|
if ((priv->ctrlmode & CAN_CTRLMODE_FD) &&
|
|
(!priv->data_bittiming.bitrate ||
|
|
(priv->data_bittiming.bitrate < priv->bittiming.bitrate))) {
|
|
netdev_err(dev, "incorrect/missing data bit-timing\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* Switch carrier on if device was stopped while in bus-off state */
|
|
if (!netif_carrier_ok(dev))
|
|
netif_carrier_on(dev);
|
|
|
|
setup_timer(&priv->restart_timer, can_restart, (unsigned long)dev);
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(open_candev);
|
|
|
|
/*
|
|
* Common close function for cleanup before the device gets closed.
|
|
*
|
|
* This function should be called in the close function of the device
|
|
* driver.
|
|
*/
|
|
void close_candev(struct net_device *dev)
|
|
{
|
|
struct can_priv *priv = netdev_priv(dev);
|
|
|
|
del_timer_sync(&priv->restart_timer);
|
|
can_flush_echo_skb(dev);
|
|
}
|
|
EXPORT_SYMBOL_GPL(close_candev);
|
|
|
|
/*
|
|
* CAN netlink interface
|
|
*/
|
|
static const struct nla_policy can_policy[IFLA_CAN_MAX + 1] = {
|
|
[IFLA_CAN_STATE] = { .type = NLA_U32 },
|
|
[IFLA_CAN_CTRLMODE] = { .len = sizeof(struct can_ctrlmode) },
|
|
[IFLA_CAN_RESTART_MS] = { .type = NLA_U32 },
|
|
[IFLA_CAN_RESTART] = { .type = NLA_U32 },
|
|
[IFLA_CAN_BITTIMING] = { .len = sizeof(struct can_bittiming) },
|
|
[IFLA_CAN_BITTIMING_CONST]
|
|
= { .len = sizeof(struct can_bittiming_const) },
|
|
[IFLA_CAN_CLOCK] = { .len = sizeof(struct can_clock) },
|
|
[IFLA_CAN_BERR_COUNTER] = { .len = sizeof(struct can_berr_counter) },
|
|
[IFLA_CAN_DATA_BITTIMING]
|
|
= { .len = sizeof(struct can_bittiming) },
|
|
[IFLA_CAN_DATA_BITTIMING_CONST]
|
|
= { .len = sizeof(struct can_bittiming_const) },
|
|
};
|
|
|
|
static int can_changelink(struct net_device *dev,
|
|
struct nlattr *tb[], struct nlattr *data[])
|
|
{
|
|
struct can_priv *priv = netdev_priv(dev);
|
|
int err;
|
|
|
|
/* We need synchronization with dev->stop() */
|
|
ASSERT_RTNL();
|
|
|
|
if (data[IFLA_CAN_BITTIMING]) {
|
|
struct can_bittiming bt;
|
|
|
|
/* Do not allow changing bittiming while running */
|
|
if (dev->flags & IFF_UP)
|
|
return -EBUSY;
|
|
memcpy(&bt, nla_data(data[IFLA_CAN_BITTIMING]), sizeof(bt));
|
|
err = can_get_bittiming(dev, &bt, priv->bittiming_const);
|
|
if (err)
|
|
return err;
|
|
memcpy(&priv->bittiming, &bt, sizeof(bt));
|
|
|
|
if (priv->do_set_bittiming) {
|
|
/* Finally, set the bit-timing registers */
|
|
err = priv->do_set_bittiming(dev);
|
|
if (err)
|
|
return err;
|
|
}
|
|
}
|
|
|
|
if (data[IFLA_CAN_CTRLMODE]) {
|
|
struct can_ctrlmode *cm;
|
|
|
|
/* Do not allow changing controller mode while running */
|
|
if (dev->flags & IFF_UP)
|
|
return -EBUSY;
|
|
cm = nla_data(data[IFLA_CAN_CTRLMODE]);
|
|
if (cm->flags & ~priv->ctrlmode_supported)
|
|
return -EOPNOTSUPP;
|
|
priv->ctrlmode &= ~cm->mask;
|
|
priv->ctrlmode |= cm->flags;
|
|
|
|
/* CAN_CTRLMODE_FD can only be set when driver supports FD */
|
|
if (priv->ctrlmode & CAN_CTRLMODE_FD)
|
|
dev->mtu = CANFD_MTU;
|
|
else
|
|
dev->mtu = CAN_MTU;
|
|
}
|
|
|
|
if (data[IFLA_CAN_RESTART_MS]) {
|
|
/* Do not allow changing restart delay while running */
|
|
if (dev->flags & IFF_UP)
|
|
return -EBUSY;
|
|
priv->restart_ms = nla_get_u32(data[IFLA_CAN_RESTART_MS]);
|
|
}
|
|
|
|
if (data[IFLA_CAN_RESTART]) {
|
|
/* Do not allow a restart while not running */
|
|
if (!(dev->flags & IFF_UP))
|
|
return -EINVAL;
|
|
err = can_restart_now(dev);
|
|
if (err)
|
|
return err;
|
|
}
|
|
|
|
if (data[IFLA_CAN_DATA_BITTIMING]) {
|
|
struct can_bittiming dbt;
|
|
|
|
/* Do not allow changing bittiming while running */
|
|
if (dev->flags & IFF_UP)
|
|
return -EBUSY;
|
|
memcpy(&dbt, nla_data(data[IFLA_CAN_DATA_BITTIMING]),
|
|
sizeof(dbt));
|
|
err = can_get_bittiming(dev, &dbt, priv->data_bittiming_const);
|
|
if (err)
|
|
return err;
|
|
memcpy(&priv->data_bittiming, &dbt, sizeof(dbt));
|
|
|
|
if (priv->do_set_data_bittiming) {
|
|
/* Finally, set the bit-timing registers */
|
|
err = priv->do_set_data_bittiming(dev);
|
|
if (err)
|
|
return err;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static size_t can_get_size(const struct net_device *dev)
|
|
{
|
|
struct can_priv *priv = netdev_priv(dev);
|
|
size_t size = 0;
|
|
|
|
if (priv->bittiming.bitrate) /* IFLA_CAN_BITTIMING */
|
|
size += nla_total_size(sizeof(struct can_bittiming));
|
|
if (priv->bittiming_const) /* IFLA_CAN_BITTIMING_CONST */
|
|
size += nla_total_size(sizeof(struct can_bittiming_const));
|
|
size += nla_total_size(sizeof(struct can_clock)); /* IFLA_CAN_CLOCK */
|
|
size += nla_total_size(sizeof(u32)); /* IFLA_CAN_STATE */
|
|
size += nla_total_size(sizeof(struct can_ctrlmode)); /* IFLA_CAN_CTRLMODE */
|
|
size += nla_total_size(sizeof(u32)); /* IFLA_CAN_RESTART_MS */
|
|
if (priv->do_get_berr_counter) /* IFLA_CAN_BERR_COUNTER */
|
|
size += nla_total_size(sizeof(struct can_berr_counter));
|
|
if (priv->data_bittiming.bitrate) /* IFLA_CAN_DATA_BITTIMING */
|
|
size += nla_total_size(sizeof(struct can_bittiming));
|
|
if (priv->data_bittiming_const) /* IFLA_CAN_DATA_BITTIMING_CONST */
|
|
size += nla_total_size(sizeof(struct can_bittiming_const));
|
|
|
|
return size;
|
|
}
|
|
|
|
static int can_fill_info(struct sk_buff *skb, const struct net_device *dev)
|
|
{
|
|
struct can_priv *priv = netdev_priv(dev);
|
|
struct can_ctrlmode cm = {.flags = priv->ctrlmode};
|
|
struct can_berr_counter bec;
|
|
enum can_state state = priv->state;
|
|
|
|
if (priv->do_get_state)
|
|
priv->do_get_state(dev, &state);
|
|
|
|
if ((priv->bittiming.bitrate &&
|
|
nla_put(skb, IFLA_CAN_BITTIMING,
|
|
sizeof(priv->bittiming), &priv->bittiming)) ||
|
|
|
|
(priv->bittiming_const &&
|
|
nla_put(skb, IFLA_CAN_BITTIMING_CONST,
|
|
sizeof(*priv->bittiming_const), priv->bittiming_const)) ||
|
|
|
|
nla_put(skb, IFLA_CAN_CLOCK, sizeof(cm), &priv->clock) ||
|
|
nla_put_u32(skb, IFLA_CAN_STATE, state) ||
|
|
nla_put(skb, IFLA_CAN_CTRLMODE, sizeof(cm), &cm) ||
|
|
nla_put_u32(skb, IFLA_CAN_RESTART_MS, priv->restart_ms) ||
|
|
|
|
(priv->do_get_berr_counter &&
|
|
!priv->do_get_berr_counter(dev, &bec) &&
|
|
nla_put(skb, IFLA_CAN_BERR_COUNTER, sizeof(bec), &bec)) ||
|
|
|
|
(priv->data_bittiming.bitrate &&
|
|
nla_put(skb, IFLA_CAN_DATA_BITTIMING,
|
|
sizeof(priv->data_bittiming), &priv->data_bittiming)) ||
|
|
|
|
(priv->data_bittiming_const &&
|
|
nla_put(skb, IFLA_CAN_DATA_BITTIMING_CONST,
|
|
sizeof(*priv->data_bittiming_const),
|
|
priv->data_bittiming_const)))
|
|
return -EMSGSIZE;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static size_t can_get_xstats_size(const struct net_device *dev)
|
|
{
|
|
return sizeof(struct can_device_stats);
|
|
}
|
|
|
|
static int can_fill_xstats(struct sk_buff *skb, const struct net_device *dev)
|
|
{
|
|
struct can_priv *priv = netdev_priv(dev);
|
|
|
|
if (nla_put(skb, IFLA_INFO_XSTATS,
|
|
sizeof(priv->can_stats), &priv->can_stats))
|
|
goto nla_put_failure;
|
|
return 0;
|
|
|
|
nla_put_failure:
|
|
return -EMSGSIZE;
|
|
}
|
|
|
|
static int can_newlink(struct net *src_net, struct net_device *dev,
|
|
struct nlattr *tb[], struct nlattr *data[])
|
|
{
|
|
return -EOPNOTSUPP;
|
|
}
|
|
|
|
static struct rtnl_link_ops can_link_ops __read_mostly = {
|
|
.kind = "can",
|
|
.maxtype = IFLA_CAN_MAX,
|
|
.policy = can_policy,
|
|
.setup = can_setup,
|
|
.newlink = can_newlink,
|
|
.changelink = can_changelink,
|
|
.get_size = can_get_size,
|
|
.fill_info = can_fill_info,
|
|
.get_xstats_size = can_get_xstats_size,
|
|
.fill_xstats = can_fill_xstats,
|
|
};
|
|
|
|
/*
|
|
* Register the CAN network device
|
|
*/
|
|
int register_candev(struct net_device *dev)
|
|
{
|
|
dev->rtnl_link_ops = &can_link_ops;
|
|
return register_netdev(dev);
|
|
}
|
|
EXPORT_SYMBOL_GPL(register_candev);
|
|
|
|
/*
|
|
* Unregister the CAN network device
|
|
*/
|
|
void unregister_candev(struct net_device *dev)
|
|
{
|
|
unregister_netdev(dev);
|
|
}
|
|
EXPORT_SYMBOL_GPL(unregister_candev);
|
|
|
|
/*
|
|
* Test if a network device is a candev based device
|
|
* and return the can_priv* if so.
|
|
*/
|
|
struct can_priv *safe_candev_priv(struct net_device *dev)
|
|
{
|
|
if ((dev->type != ARPHRD_CAN) || (dev->rtnl_link_ops != &can_link_ops))
|
|
return NULL;
|
|
|
|
return netdev_priv(dev);
|
|
}
|
|
EXPORT_SYMBOL_GPL(safe_candev_priv);
|
|
|
|
static __init int can_dev_init(void)
|
|
{
|
|
int err;
|
|
|
|
can_led_notifier_init();
|
|
|
|
err = rtnl_link_register(&can_link_ops);
|
|
if (!err)
|
|
printk(KERN_INFO MOD_DESC "\n");
|
|
|
|
return err;
|
|
}
|
|
module_init(can_dev_init);
|
|
|
|
static __exit void can_dev_exit(void)
|
|
{
|
|
rtnl_link_unregister(&can_link_ops);
|
|
|
|
can_led_notifier_exit();
|
|
}
|
|
module_exit(can_dev_exit);
|
|
|
|
MODULE_ALIAS_RTNL_LINK("can");
|