can: CAN Network device driver and Netlink interface
The CAN network device driver interface provides a generic interface to setup, configure and monitor CAN network devices. It exports a set of common data structures and functions, which all real CAN network device drivers should use. Please have a look to the SJA1000 or MSCAN driver to understand how to use them. The name of the module is can-dev.ko. Furthermore, it adds a Netlink interface allowing to configure the CAN device using the program "ip" from the iproute2 utility suite. For further information please check "Documentation/networking/can.txt" Signed-off-by: Wolfgang Grandegger <wg@grandegger.com> Signed-off-by: Oliver Hartkopp <oliver.hartkopp@volkswagen.de> Signed-off-by: David S. Miller <davem@davemloft.net>hifive-unleashed-5.1
Wolfgang Grandegger
David S. Miller
parent
4261a2043f
commit
39549eef35
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@ -12,6 +12,29 @@ config CAN_VCAN
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This driver can also be built as a module. If so, the module
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will be called vcan.
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config CAN_DEV
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tristate "Platform CAN drivers with Netlink support"
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depends on CAN
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default Y
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---help---
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Enables the common framework for platform CAN drivers with Netlink
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support. This is the standard library for CAN drivers.
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If unsure, say Y.
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config CAN_CALC_BITTIMING
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bool "CAN bit-timing calculation"
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depends on CAN_DEV
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default Y
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---help---
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If enabled, CAN bit-timing parameters will be calculated for the
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bit-rate specified via Netlink argument "bitrate" when the device
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get started. This works fine for the most common CAN controllers
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with standard bit-rates but may fail for exotic bit-rates or CAN
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source clock frequencies. Disabling saves some space, but then the
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bit-timing parameters must be specified directly using the Netlink
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arguments "tq", "prop_seg", "phase_seg1", "phase_seg2" and "sjw".
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If unsure, say Y.
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config CAN_DEBUG_DEVICES
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bool "CAN devices debugging messages"
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depends on CAN
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@ -3,3 +3,8 @@
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#
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obj-$(CONFIG_CAN_VCAN) += vcan.o
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obj-$(CONFIG_CAN_DEV) += can-dev.o
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can-dev-y := dev.o
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ccflags-$(CONFIG_CAN_DEBUG_DEVICES) := -DDEBUG
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@ -0,0 +1,657 @@
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/*
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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, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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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/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/netlink.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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#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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{
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struct can_priv *priv = netdev_priv(dev);
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const struct can_bittiming_const *btc = priv->bittiming_const;
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long rate, best_rate = 0;
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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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u64 v64;
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if (!priv->bittiming_const)
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return -ENOTSUPP;
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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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best_rate = rate;
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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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dev_err(dev->dev.parent,
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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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dev_warn(dev->dev.parent, "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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bt->sjw = 1;
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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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{
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dev_err(dev->dev.parent, "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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{
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struct can_priv *priv = netdev_priv(dev);
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const struct can_bittiming_const *btc = priv->bittiming_const;
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int tseg1, alltseg;
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u64 brp64;
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if (!priv->bittiming_const)
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return -ENOTSUPP;
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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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int can_get_bittiming(struct net_device *dev, struct can_bittiming *bt)
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{
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struct can_priv *priv = netdev_priv(dev);
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int err;
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/* Check if the CAN device has bit-timing parameters */
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if (priv->bittiming_const) {
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/* Non-expert mode? Check if the bitrate has been pre-defined */
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if (!bt->tq)
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/* Determine bit-timing parameters */
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err = can_calc_bittiming(dev, bt);
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else
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/* Check bit-timing params and calculate proper brp */
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err = can_fixup_bittiming(dev, bt);
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if (err)
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return err;
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}
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return 0;
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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 < CAN_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, int idx)
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{
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struct can_priv *priv = netdev_priv(dev);
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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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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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struct sock *srcsk = skb->sk;
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if (atomic_read(&skb->users) != 1) {
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struct sk_buff *old_skb = skb;
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skb = skb_clone(old_skb, GFP_ATOMIC);
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kfree_skb(old_skb);
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if (!skb)
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return;
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} else
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skb_orphan(skb);
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skb->sk = srcsk;
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/* make settings for echo to reduce code in irq context */
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skb->protocol = htons(ETH_P_CAN);
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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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dev_err(dev->dev.parent, "%s: BUG! echo_skb is occupied!\n",
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__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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void can_get_echo_skb(struct net_device *dev, int idx)
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{
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struct can_priv *priv = netdev_priv(dev);
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if ((dev->flags & IFF_ECHO) && priv->echo_skb[idx]) {
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netif_rx(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_get_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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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 = dev_alloc_skb(sizeof(struct can_frame));
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if (skb == NULL) {
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err = -ENOMEM;
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goto out;
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}
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skb->dev = dev;
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skb->protocol = htons(ETH_P_CAN);
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cf = (struct can_frame *)skb_put(skb, sizeof(struct can_frame));
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memset(cf, 0, sizeof(struct can_frame));
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cf->can_id = CAN_ERR_FLAG | CAN_ERR_RESTARTED;
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cf->can_dlc = CAN_ERR_DLC;
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netif_rx(skb);
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dev->last_rx = jiffies;
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stats->rx_packets++;
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stats->rx_bytes += cf->can_dlc;
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dev_dbg(dev->dev.parent, "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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out:
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netif_carrier_on(dev);
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if (err)
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dev_err(dev->dev.parent, "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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* 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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/* 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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* 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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||||
|
||||
dev_dbg(dev->dev.parent, "bus-off\n");
|
||||
|
||||
netif_carrier_off(dev);
|
||||
priv->can_stats.bus_off++;
|
||||
|
||||
if (priv->restart_ms)
|
||||
mod_timer(&priv->restart_timer,
|
||||
jiffies + (priv->restart_ms * HZ) / 1000);
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(can_bus_off);
|
||||
|
||||
static void can_setup(struct net_device *dev)
|
||||
{
|
||||
dev->type = ARPHRD_CAN;
|
||||
dev->mtu = sizeof(struct can_frame);
|
||||
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_NO_CSUM;
|
||||
}
|
||||
|
||||
/*
|
||||
* Allocate and setup space for the CAN network device
|
||||
*/
|
||||
struct net_device *alloc_candev(int sizeof_priv)
|
||||
{
|
||||
struct net_device *dev;
|
||||
struct can_priv *priv;
|
||||
|
||||
dev = alloc_netdev(sizeof_priv, "can%d", can_setup);
|
||||
if (!dev)
|
||||
return NULL;
|
||||
|
||||
priv = netdev_priv(dev);
|
||||
|
||||
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);
|
||||
|
||||
/*
|
||||
* 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.tq && !priv->bittiming.bitrate) {
|
||||
dev_err(dev->dev.parent, "bit-timing not yet defined\n");
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
setup_timer(&priv->restart_timer, can_restart, (unsigned long)dev);
|
||||
|
||||
return 0;
|
||||
}
|
||||
EXPORT_SYMBOL(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);
|
||||
|
||||
if (del_timer_sync(&priv->restart_timer))
|
||||
dev_put(dev);
|
||||
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) },
|
||||
};
|
||||
|
||||
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_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]);
|
||||
priv->ctrlmode &= ~cm->mask;
|
||||
priv->ctrlmode |= cm->flags;
|
||||
}
|
||||
|
||||
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));
|
||||
if ((!bt.bitrate && !bt.tq) || (bt.bitrate && bt.tq))
|
||||
return -EINVAL;
|
||||
err = can_get_bittiming(dev, &bt);
|
||||
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_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;
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
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};
|
||||
enum can_state state = priv->state;
|
||||
|
||||
if (priv->do_get_state)
|
||||
priv->do_get_state(dev, &state);
|
||||
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);
|
||||
NLA_PUT(skb, IFLA_CAN_BITTIMING,
|
||||
sizeof(priv->bittiming), &priv->bittiming);
|
||||
NLA_PUT(skb, IFLA_CAN_CLOCK, sizeof(cm), &priv->clock);
|
||||
if (priv->bittiming_const)
|
||||
NLA_PUT(skb, IFLA_CAN_BITTIMING_CONST,
|
||||
sizeof(*priv->bittiming_const), priv->bittiming_const);
|
||||
|
||||
return 0;
|
||||
|
||||
nla_put_failure:
|
||||
return -EMSGSIZE;
|
||||
}
|
||||
|
||||
static int can_fill_xstats(struct sk_buff *skb, const struct net_device *dev)
|
||||
{
|
||||
struct can_priv *priv = netdev_priv(dev);
|
||||
|
||||
NLA_PUT(skb, IFLA_INFO_XSTATS,
|
||||
sizeof(priv->can_stats), &priv->can_stats);
|
||||
|
||||
return 0;
|
||||
|
||||
nla_put_failure:
|
||||
return -EMSGSIZE;
|
||||
}
|
||||
|
||||
static struct rtnl_link_ops can_link_ops __read_mostly = {
|
||||
.kind = "can",
|
||||
.maxtype = IFLA_CAN_MAX,
|
||||
.policy = can_policy,
|
||||
.setup = can_setup,
|
||||
.changelink = can_changelink,
|
||||
.fill_info = can_fill_info,
|
||||
.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);
|
||||
|
||||
static __init int can_dev_init(void)
|
||||
{
|
||||
int err;
|
||||
|
||||
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);
|
||||
}
|
||||
module_exit(can_dev_exit);
|
||||
|
||||
MODULE_ALIAS_RTNL_LINK("can");
|
||||
|
|
@ -1,3 +1,4 @@
|
|||
header-y += raw.h
|
||||
header-y += bcm.h
|
||||
header-y += error.h
|
||||
header-y += netlink.h
|
||||
|
|
|
|||
|
|
@ -0,0 +1,70 @@
|
|||
/*
|
||||
* linux/can/dev.h
|
||||
*
|
||||
* Definitions for the CAN network device driver interface
|
||||
*
|
||||
* Copyright (C) 2006 Andrey Volkov <avolkov@varma-el.com>
|
||||
* Varma Electronics Oy
|
||||
*
|
||||
* Copyright (C) 2008 Wolfgang Grandegger <wg@grandegger.com>
|
||||
*
|
||||
* Send feedback to <socketcan-users@lists.berlios.de>
|
||||
*/
|
||||
|
||||
#ifndef CAN_DEV_H
|
||||
#define CAN_DEV_H
|
||||
|
||||
#include <linux/can/netlink.h>
|
||||
#include <linux/can/error.h>
|
||||
|
||||
/*
|
||||
* CAN mode
|
||||
*/
|
||||
enum can_mode {
|
||||
CAN_MODE_STOP = 0,
|
||||
CAN_MODE_START,
|
||||
CAN_MODE_SLEEP
|
||||
};
|
||||
|
||||
/*
|
||||
* CAN common private data
|
||||
*/
|
||||
#define CAN_ECHO_SKB_MAX 4
|
||||
|
||||
struct can_priv {
|
||||
struct can_device_stats can_stats;
|
||||
|
||||
struct can_bittiming bittiming;
|
||||
struct can_bittiming_const *bittiming_const;
|
||||
struct can_clock clock;
|
||||
|
||||
enum can_state state;
|
||||
u32 ctrlmode;
|
||||
|
||||
int restart_ms;
|
||||
struct timer_list restart_timer;
|
||||
|
||||
struct sk_buff *echo_skb[CAN_ECHO_SKB_MAX];
|
||||
|
||||
int (*do_set_bittiming)(struct net_device *dev);
|
||||
int (*do_set_mode)(struct net_device *dev, enum can_mode mode);
|
||||
int (*do_get_state)(const struct net_device *dev,
|
||||
enum can_state *state);
|
||||
};
|
||||
|
||||
struct net_device *alloc_candev(int sizeof_priv);
|
||||
void free_candev(struct net_device *dev);
|
||||
|
||||
int open_candev(struct net_device *dev);
|
||||
void close_candev(struct net_device *dev);
|
||||
|
||||
int register_candev(struct net_device *dev);
|
||||
void unregister_candev(struct net_device *dev);
|
||||
|
||||
int can_restart_now(struct net_device *dev);
|
||||
void can_bus_off(struct net_device *dev);
|
||||
|
||||
void can_put_echo_skb(struct sk_buff *skb, struct net_device *dev, int idx);
|
||||
void can_get_echo_skb(struct net_device *dev, int idx);
|
||||
|
||||
#endif /* CAN_DEV_H */
|
||||
|
|
@ -0,0 +1,113 @@
|
|||
/*
|
||||
* linux/can/netlink.h
|
||||
*
|
||||
* Definitions for the CAN netlink interface
|
||||
*
|
||||
* Copyright (c) 2009 Wolfgang Grandegger <wg@grandegger.com>
|
||||
*
|
||||
* Send feedback to <socketcan-users@lists.berlios.de>
|
||||
*
|
||||
*/
|
||||
|
||||
#ifndef CAN_NETLINK_H
|
||||
#define CAN_NETLINK_H
|
||||
|
||||
#include <linux/types.h>
|
||||
|
||||
/*
|
||||
* CAN bit-timing parameters
|
||||
*
|
||||
* For futher information, please read chapter "8 BIT TIMING
|
||||
* REQUIREMENTS" of the "Bosch CAN Specification version 2.0"
|
||||
* at http://www.semiconductors.bosch.de/pdf/can2spec.pdf.
|
||||
*/
|
||||
struct can_bittiming {
|
||||
__u32 bitrate; /* Bit-rate in bits/second */
|
||||
__u32 sample_point; /* Sample point in one-tenth of a percent */
|
||||
__u32 tq; /* Time quanta (TQ) in nanoseconds */
|
||||
__u32 prop_seg; /* Propagation segment in TQs */
|
||||
__u32 phase_seg1; /* Phase buffer segment 1 in TQs */
|
||||
__u32 phase_seg2; /* Phase buffer segment 2 in TQs */
|
||||
__u32 sjw; /* Synchronisation jump width in TQs */
|
||||
__u32 brp; /* Bit-rate prescaler */
|
||||
};
|
||||
|
||||
/*
|
||||
* CAN harware-dependent bit-timing constant
|
||||
*
|
||||
* Used for calculating and checking bit-timing parameters
|
||||
*/
|
||||
struct can_bittiming_const {
|
||||
char name[16]; /* Name of the CAN controller hardware */
|
||||
__u32 tseg1_min; /* Time segement 1 = prop_seg + phase_seg1 */
|
||||
__u32 tseg1_max;
|
||||
__u32 tseg2_min; /* Time segement 2 = phase_seg2 */
|
||||
__u32 tseg2_max;
|
||||
__u32 sjw_max; /* Synchronisation jump width */
|
||||
__u32 brp_min; /* Bit-rate prescaler */
|
||||
__u32 brp_max;
|
||||
__u32 brp_inc;
|
||||
};
|
||||
|
||||
/*
|
||||
* CAN clock parameters
|
||||
*/
|
||||
struct can_clock {
|
||||
__u32 freq; /* CAN system clock frequency in Hz */
|
||||
};
|
||||
|
||||
/*
|
||||
* CAN operational and error states
|
||||
*/
|
||||
enum can_state {
|
||||
CAN_STATE_ERROR_ACTIVE = 0, /* RX/TX error count < 96 */
|
||||
CAN_STATE_ERROR_WARNING, /* RX/TX error count < 128 */
|
||||
CAN_STATE_ERROR_PASSIVE, /* RX/TX error count < 256 */
|
||||
CAN_STATE_BUS_OFF, /* RX/TX error count >= 256 */
|
||||
CAN_STATE_STOPPED, /* Device is stopped */
|
||||
CAN_STATE_SLEEPING, /* Device is sleeping */
|
||||
CAN_STATE_MAX
|
||||
};
|
||||
|
||||
/*
|
||||
* CAN controller mode
|
||||
*/
|
||||
struct can_ctrlmode {
|
||||
__u32 mask;
|
||||
__u32 flags;
|
||||
};
|
||||
|
||||
#define CAN_CTRLMODE_LOOPBACK 0x1 /* Loopback mode */
|
||||
#define CAN_CTRLMODE_LISTENONLY 0x2 /* Listen-only mode */
|
||||
#define CAN_CTRLMODE_3_SAMPLES 0x4 /* Triple sampling mode */
|
||||
|
||||
/*
|
||||
* CAN device statistics
|
||||
*/
|
||||
struct can_device_stats {
|
||||
__u32 bus_error; /* Bus errors */
|
||||
__u32 error_warning; /* Changes to error warning state */
|
||||
__u32 error_passive; /* Changes to error passive state */
|
||||
__u32 bus_off; /* Changes to bus off state */
|
||||
__u32 arbitration_lost; /* Arbitration lost errors */
|
||||
__u32 restarts; /* CAN controller re-starts */
|
||||
};
|
||||
|
||||
/*
|
||||
* CAN netlink interface
|
||||
*/
|
||||
enum {
|
||||
IFLA_CAN_UNSPEC,
|
||||
IFLA_CAN_BITTIMING,
|
||||
IFLA_CAN_BITTIMING_CONST,
|
||||
IFLA_CAN_CLOCK,
|
||||
IFLA_CAN_STATE,
|
||||
IFLA_CAN_CTRLMODE,
|
||||
IFLA_CAN_RESTART_MS,
|
||||
IFLA_CAN_RESTART,
|
||||
__IFLA_CAN_MAX
|
||||
};
|
||||
|
||||
#define IFLA_CAN_MAX (__IFLA_CAN_MAX - 1)
|
||||
|
||||
#endif /* CAN_NETLINK_H */
|
||||
Loading…
Reference in New Issue