From 5251188673e425bfddcbbe7fad19f7e0e945bf62 Mon Sep 17 00:00:00 2001 From: Benedikt Spranger Date: Thu, 29 Nov 2012 19:48:45 +0100 Subject: link: basic socket-CAN support Controller Area Network (CAN) is a networking technology which has widespread use in automation, embedded devices and automotive fields. The socket-CAN package is an implementation of CAN protocols for Linux. All socket-CAN related configurations are carried out through Netlink. Add basic socket-CAN support to libnl to be able to configure CAN devices with libnl. Signed-off-by: Benedikt Spranger Signed-off-by: Thomas Graf --- lib/route/link/can.c | 404 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 404 insertions(+) create mode 100644 lib/route/link/can.c (limited to 'lib/route/link/can.c') diff --git a/lib/route/link/can.c b/lib/route/link/can.c new file mode 100644 index 0000000..a987ca3 --- /dev/null +++ b/lib/route/link/can.c @@ -0,0 +1,404 @@ +/* + * lib/route/link/can.c CAN Link Info + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation version 2.1 + * of the License. + * + * Copyright (c) 2012 Benedikt Spranger + */ + +/** + * @ingroup link + * @defgroup can CAN + * Controller Area Network link module + * + * @details + * \b Link Type Name: "can" + * + * @route_doc{link_can, CAN Documentation} + * + * @{ + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +/** @cond SKIP */ +#define CAN_HAS_BITTIMING (1<<0) +#define CAN_HAS_BITTIMING_CONST (1<<1) +#define CAN_HAS_CLOCK (1<<2) +#define CAN_HAS_STATE (1<<3) +#define CAN_HAS_CTRLMODE (1<<4) +#define CAN_HAS_RESTART_MS (1<<5) +#define CAN_HAS_RESTART (1<<6) +#define CAN_HAS_BERR_COUNTER (1<<7) + +struct can_info { + uint32_t ci_state; + uint32_t ci_restart; + uint32_t ci_restart_ms; + struct can_ctrlmode ci_ctrlmode; + struct can_bittiming ci_bittiming; + struct can_bittiming_const ci_bittiming_const; + struct can_clock ci_clock; + struct can_berr_counter ci_berr_counter; + uint32_t ci_mask; +}; + +/** @endcond */ + +static struct nla_policy can_policy[IFLA_CAN_MAX + 1] = { + [IFLA_CAN_STATE] = { .type = NLA_U32 }, + [IFLA_CAN_CTRLMODE] = { .minlen = sizeof(struct can_ctrlmode) }, + [IFLA_CAN_RESTART_MS] = { .type = NLA_U32 }, + [IFLA_CAN_RESTART] = { .type = NLA_U32 }, + [IFLA_CAN_BITTIMING] = { .minlen = sizeof(struct can_bittiming) }, + [IFLA_CAN_BITTIMING_CONST] + = { .minlen = sizeof(struct can_bittiming_const) }, + [IFLA_CAN_CLOCK] = { .minlen = sizeof(struct can_clock) }, + [IFLA_CAN_BERR_COUNTER] = { .minlen = sizeof(struct can_berr_counter) }, +}; + +static int can_alloc(struct rtnl_link *link) +{ + struct can_info *ci; + + ci = calloc(1, sizeof(*ci)); + if (!ci) + return -NLE_NOMEM; + + link->l_info = ci; + + return 0; +} + +static int can_parse(struct rtnl_link *link, struct nlattr *data, + struct nlattr *xstats) +{ + struct nlattr *tb[IFLA_CAN_MAX+1]; + struct can_info *ci; + int err; + + NL_DBG(3, "Parsing CAN link info"); + + if ((err = nla_parse_nested(tb, IFLA_CAN_MAX, data, can_policy)) < 0) + goto errout; + + if ((err = can_alloc(link)) < 0) + goto errout; + + ci = link->l_info; + + if (tb[IFLA_CAN_STATE]) { + ci->ci_state = nla_get_u32(tb[IFLA_CAN_STATE]); + ci->ci_mask |= CAN_HAS_STATE; + } + + if (tb[IFLA_CAN_RESTART]) { + ci->ci_restart = nla_get_u32(tb[IFLA_CAN_RESTART]); + ci->ci_mask |= CAN_HAS_RESTART; + } + + if (tb[IFLA_CAN_RESTART_MS]) { + ci->ci_restart_ms = nla_get_u32(tb[IFLA_CAN_RESTART_MS]); + ci->ci_mask |= CAN_HAS_RESTART_MS; + } + + if (tb[IFLA_CAN_CTRLMODE]) { + nla_memcpy(&ci->ci_ctrlmode, tb[IFLA_CAN_CTRLMODE], + sizeof(ci->ci_ctrlmode)); + ci->ci_mask |= CAN_HAS_CTRLMODE; + } + + if (tb[IFLA_CAN_BITTIMING]) { + nla_memcpy(&ci->ci_bittiming, tb[IFLA_CAN_BITTIMING], + sizeof(ci->ci_bittiming)); + ci->ci_mask |= CAN_HAS_BITTIMING; + } + + if (tb[IFLA_CAN_BITTIMING_CONST]) { + nla_memcpy(&ci->ci_bittiming_const, + tb[IFLA_CAN_BITTIMING_CONST], + sizeof(ci->ci_bittiming_const)); + ci->ci_mask |= CAN_HAS_BITTIMING_CONST; + } + + if (tb[IFLA_CAN_CLOCK]) { + nla_memcpy(&ci->ci_clock, tb[IFLA_CAN_CLOCK], + sizeof(ci->ci_clock)); + ci->ci_mask |= CAN_HAS_CLOCK; + } + + if (tb[IFLA_CAN_BERR_COUNTER]) { + nla_memcpy(&ci->ci_berr_counter, tb[IFLA_CAN_BERR_COUNTER], + sizeof(ci->ci_berr_counter)); + ci->ci_mask |= CAN_HAS_BERR_COUNTER; + } + + err = 0; +errout: + return err; +} + +static void can_free(struct rtnl_link *link) +{ + struct can_info *ci = link->l_info; + + free(ci); + link->l_info = NULL; +} + +static char *print_can_state (uint32_t state) +{ + char *text; + + switch (state) + { + case CAN_STATE_ERROR_ACTIVE: + text = "error active"; + break; + case CAN_STATE_ERROR_WARNING: + text = "error warning"; + break; + case CAN_STATE_ERROR_PASSIVE: + text = "error passive"; + break; + case CAN_STATE_BUS_OFF: + text = "bus off"; + break; + case CAN_STATE_STOPPED: + text = "stopped"; + break; + case CAN_STATE_SLEEPING: + text = "sleeping"; + break; + default: + text = "unknown state"; + } + + return text; +} + +static void can_dump_line(struct rtnl_link *link, struct nl_dump_params *p) +{ + struct can_info *ci = link->l_info; + char buf [64]; + + rtnl_link_can_ctrlmode2str(ci->ci_ctrlmode.flags, buf, sizeof(buf)); + nl_dump(p, "bitrate %d %s <%s>", + ci->ci_bittiming.bitrate, print_can_state(ci->ci_state), buf); +} + +static void can_dump_details(struct rtnl_link *link, struct nl_dump_params *p) +{ + struct can_info *ci = link->l_info; + char buf [64]; + + rtnl_link_can_ctrlmode2str(ci->ci_ctrlmode.flags, buf, sizeof(buf)); + nl_dump(p, " bitrate %d %s <%s>", + ci->ci_bittiming.bitrate, print_can_state(ci->ci_state), buf); + + if (ci->ci_mask & CAN_HAS_RESTART) { + if (ci->ci_restart) + nl_dump_line(p," restarting\n"); + } + + if (ci->ci_mask & CAN_HAS_RESTART_MS) { + nl_dump_line(p," restart interval %d ms\n", + ci->ci_restart_ms); + } + + if (ci->ci_mask & CAN_HAS_BITTIMING) { + nl_dump_line(p," sample point %f %%\n", + ((float) ci->ci_bittiming.sample_point)/10); + nl_dump_line(p," time quanta %d ns\n", + ci->ci_bittiming.tq); + nl_dump_line(p," propagation segment %d tq\n", + ci->ci_bittiming.prop_seg); + nl_dump_line(p," phase buffer segment1 %d tq\n", + ci->ci_bittiming.phase_seg1); + nl_dump_line(p," phase buffer segment2 %d tq\n", + ci->ci_bittiming.phase_seg2); + nl_dump_line(p," synchronisation jump width %d tq\n", + ci->ci_bittiming.sjw); + nl_dump_line(p," bitrate prescaler %d\n", + ci->ci_bittiming.brp); + } + + if (ci->ci_mask & CAN_HAS_BITTIMING_CONST) { + nl_dump_line(p," minimum tsig1 %d tq\n", + ci->ci_bittiming_const.tseg1_min); + nl_dump_line(p," maximum tsig1 %d tq\n", + ci->ci_bittiming_const.tseg1_max); + nl_dump_line(p," minimum tsig2 %d tq\n", + ci->ci_bittiming_const.tseg2_min); + nl_dump_line(p," maximum tsig2 %d tq\n", + ci->ci_bittiming_const.tseg2_max); + nl_dump_line(p," maximum sjw %d tq\n", + ci->ci_bittiming_const.sjw_max); + nl_dump_line(p," minimum brp %d\n", + ci->ci_bittiming_const.brp_min); + nl_dump_line(p," maximum brp %d\n", + ci->ci_bittiming_const.brp_max); + nl_dump_line(p," brp increment %d\n", + ci->ci_bittiming_const.brp_inc); + } + + if (ci->ci_mask & CAN_HAS_CLOCK) { + nl_dump_line(p," base freq %d Hz\n", ci->ci_clock); + + } + + if (ci->ci_mask & CAN_HAS_BERR_COUNTER) { + nl_dump_line(p," bus error RX %d\n", + ci->ci_berr_counter.rxerr); + nl_dump_line(p," bus error TX %d\n", + ci->ci_berr_counter.txerr); + } + + return; +} + +static int can_clone(struct rtnl_link *dst, struct rtnl_link *src) +{ + struct can_info *cdst, *csrc = src->l_info; + int ret; + + dst->l_info = NULL; + ret = rtnl_link_set_type(dst, "can"); + if (ret < 0) + return ret; + + cdst = malloc(sizeof(*cdst)); + if (!cdst) + return -NLE_NOMEM; + + *cdst = *csrc; + dst->l_info = cdst; + + return 0; +} + +static int can_put_attrs(struct nl_msg *msg, struct rtnl_link *link) +{ + struct can_info *ci = link->l_info; + struct nlattr *data; + + data = nla_nest_start(msg, IFLA_INFO_DATA); + if (!data) + return -NLE_MSGSIZE; + + if (ci->ci_mask & CAN_HAS_RESTART) + NLA_PUT_U32(msg, CAN_HAS_RESTART, ci->ci_restart); + + if (ci->ci_mask & CAN_HAS_RESTART_MS) + NLA_PUT_U32(msg, CAN_HAS_RESTART_MS, ci->ci_restart_ms); + + if (ci->ci_mask & CAN_HAS_CTRLMODE) + NLA_PUT(msg, CAN_HAS_CTRLMODE, sizeof(ci->ci_ctrlmode), + &ci->ci_ctrlmode); + + if (ci->ci_mask & CAN_HAS_BITTIMING) + NLA_PUT(msg, CAN_HAS_BITTIMING, sizeof(ci->ci_bittiming), + &ci->ci_bittiming); + + if (ci->ci_mask & CAN_HAS_BITTIMING_CONST) + NLA_PUT(msg, CAN_HAS_BITTIMING_CONST, + sizeof(ci->ci_bittiming_const), + &ci->ci_bittiming_const); + + if (ci->ci_mask & CAN_HAS_CLOCK) + NLA_PUT(msg, CAN_HAS_CLOCK, sizeof(ci->ci_clock), + &ci->ci_clock); + +nla_put_failure: + + return 0; +} + +static struct rtnl_link_info_ops can_info_ops = { + .io_name = "can", + .io_alloc = can_alloc, + .io_parse = can_parse, + .io_dump = { + [NL_DUMP_LINE] = can_dump_line, + [NL_DUMP_DETAILS] = can_dump_details, + }, + .io_clone = can_clone, + .io_put_attrs = can_put_attrs, + .io_free = can_free, +}; + +/** @cond SKIP */ +#define IS_CAN_LINK_ASSERT(link) \ + if ((link)->l_info_ops != &can_info_ops) { \ + APPBUG("Link is not a CAN link. set type \"can\" first."); \ + return -NLE_OPNOTSUPP; \ + } +/** @endcond */ + +/** + * @name CAN Object + * @{ + */ + +/** + * Check if link is a CAN link + * @arg link Link object + * + * @return True if link is a CAN link, otherwise false is returned. + */ +int rtnl_link_is_can(struct rtnl_link *link) +{ + return link->l_info_ops && !strcmp(link->l_info_ops->io_name, "can"); +} + +/** @} */ + +/** + * @name Control Mode Translation + * @{ + */ + +static const struct trans_tbl can_ctrlmode[] = { + __ADD(CAN_CTRLMODE_LOOPBACK, loopback) + __ADD(CAN_CTRLMODE_LISTENONLY, listen-only) + __ADD(CAN_CTRLMODE_3_SAMPLES, triple-sampling) + __ADD(CAN_CTRLMODE_ONE_SHOT, one-shot) + __ADD(CAN_CTRLMODE_BERR_REPORTING, berr-reporting) +}; + +char *rtnl_link_can_ctrlmode2str(int ctrlmode, char *buf, size_t len) +{ + return __flags2str(ctrlmode, buf, len, can_ctrlmode, + ARRAY_SIZE(can_ctrlmode)); +} + +int rtnl_link_can_str2ctrlmode(const char *name) +{ + return __str2flags(name, can_ctrlmode, ARRAY_SIZE(can_ctrlmode)); +} + +/** @} */ + +static void __init can_init(void) +{ + rtnl_link_register_info(&can_info_ops); +} + +static void __exit can_exit(void) +{ + rtnl_link_unregister_info(&can_info_ops); +} + +/** @} */ -- cgit v1.2.1