Subject: [PATCH 2/2] iproute2: Support for the CAN netlink

From: Wolfgang Grandegger <[email-masked]>
Date: Tue, 12 May 2009 11:42:50 +0200

Signed-off-by: Wolfgang Grandegger <[email-masked]>
---
 include/linux/can/netlink.h |  113 ++++++++++++++++++
 ip/Makefile                 |    2 
 ip/iplink.c                 |    2 
 ip/iplink_can.c             |  264 ++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 379 insertions(+), 2 deletions(-)

Index: iproute2/ip/Makefile
===================================================================
--- iproute2.orig/ip/Makefile
+++ iproute2/ip/Makefile
@@ -2,7 +2,7 @@ IPOBJ=ip.o ipaddress.o ipaddrlabel.o ipr
     rtm_map.o iptunnel.o ip6tunnel.o tunnel.o ipneigh.o ipntable.o iplink.o \
     ipmaddr.o ipmonitor.o ipmroute.o ipprefix.o \
     ipxfrm.o xfrm_state.o xfrm_policy.o xfrm_monitor.o \
-    iplink_vlan.o link_veth.o link_gre.o
+    iplink_vlan.o link_veth.o link_gre.o iplink_can.o
 
 RTMONOBJ=rtmon.o
 
Index: iproute2/ip/iplink_can.c
===================================================================
--- /dev/null
+++ iproute2/ip/iplink_can.c
@@ -0,0 +1,264 @@
+/*
+ * iplink_can.c	CAN device support
+ *
+ *              This program is free software; you can redistribute it and/or
+ *              modify it under the terms of the GNU General Public License
+ *              as published by the Free Software Foundation; either version
+ *              2 of the License, or (at your option) any later version.
+ *
+ * Authors:     Wolfgang Grandegger <[email-masked]>
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <linux/can/netlink.h>
+
+#include "rt_names.h"
+#include "utils.h"
+#include "ip_common.h"
+
+static void usage(void)
+{
+	fprintf(stderr,
+		"Usage: ip link set DEVICE type can\n"
+	        "\t[ bitrate BITRATE [ sample-point SAMPLE-POINT] ] | \n"
+	        "\t[ tq TQ prop-seg PROP_SEG phase-seg1 PHASE-SEG1\n "
+		"\t  phase-seg2 PHASE-SEG2 [ sjw SJW ] ]\n"
+		"\n"
+	        "\t[ loopback { on | off } ]\n"
+	        "\t[ listen-only { on | off } ]\n"
+	        "\t[ triple-sampling { on | off } ]\n"
+		"\n"
+	        "\t[ restart-ms TIME-MS ]\n"
+	        "\t[ restart ]\n"
+		"\n"
+		"\tWhere: BITRATE       := { 1..1000000 }\n"
+		"\t       SAMPLE-POINT  := { 0.000..0.999 }\n"
+		"\t       TQ            := { NUMBER }\n"
+		"\t       PROP-SEG      := { 1..8 }\n"
+		"\t       PHASE-SEG1    := { 1..8 }\n"
+		"\t       PHASE-SEG2    := { 1..8 }\n"
+		"\t       SJW           := { 1..4 }\n"
+		"\t       RESTART-MS    := { 0 | NUMBER }\n"
+		);
+}
+
+static int get_float(float *val, const char *arg)
+{
+	float res;
+	char *ptr;
+
+	if (!arg || !*arg)
+		return -1;
+	res = strtof(arg, &ptr);
+	if (!ptr || ptr == arg || *ptr)
+		return -1;
+	*val = res;
+	return 0;
+}
+
+static void set_ctrlmode(char* name, char *arg,
+			 struct can_ctrlmode *cm, __u32 flags)
+{
+	if (strcmp(arg, "on") == 0) {
+		cm->flags |= flags;
+	} else if (strcmp(arg, "off") != 0) {
+		fprintf(stderr,
+			"Error: argument of \"%s\" must be \"on\" or \"off\"\n",
+			name);
+		exit(-1);
+	}
+	cm->mask |= flags;
+}
+
+static void print_ctrlmode(FILE *f, __u32 cm)
+{
+	fprintf(f, "<");
+#define _PF(cmflag, cmname)					\
+	if (cm & cmflag) {					\
+		cm &= ~cmflag;					\
+		fprintf(f, "%s%s", cmname, cm ? "," : "");	\
+	}
+	_PF(CAN_CTRLMODE_LOOPBACK, "LOOPBACK");
+	_PF(CAN_CTRLMODE_LISTENONLY, "LISTEN-ONLY");
+	_PF(CAN_CTRLMODE_3_SAMPLES, "TRIPLE-SAMPLING");
+#undef _PF
+	if (cm)
+		fprintf(f, "%x", cm);
+	fprintf(f, "> ");
+}
+
+static int can_parse_opt(struct link_util *lu, int argc, char **argv,
+			 struct nlmsghdr *n)
+{
+	struct can_bittiming bt;
+	struct can_ctrlmode cm = {0, 0};
+
+	memset(&bt, 0, sizeof(bt));
+	while (argc > 0) {
+		if (matches(*argv, "bitrate") == 0) {
+			NEXT_ARG();
+			if (get_u32(&bt.bitrate, *argv, 0))
+				invarg("invalid \"bitrate\" value\n", *argv);
+		} else if (matches(*argv, "sample-point") == 0) {
+			float sp;
+
+			NEXT_ARG();
+			if (get_float(&sp, *argv))
+				invarg("invalid \"sample-point\" value\n",
+				       *argv);
+			bt.sample_point = (__u32)(sp * 1000);
+		} else if (matches(*argv, "tq") == 0) {
+			NEXT_ARG();
+			if (get_u32(&bt.tq, *argv, 0))
+				invarg("invalid \"tq\" value\n", *argv);
+		} else if (matches(*argv, "prop-seg") == 0) {
+			NEXT_ARG();
+			if (get_u32(&bt.prop_seg, *argv, 0))
+				invarg("invalid \"prop-seg\" value\n", *argv);
+		} else if (matches(*argv, "phase-seg1") == 0) {
+			NEXT_ARG();
+			if (get_u32(&bt.phase_seg1, *argv, 0))
+				invarg("invalid \"phase-seg1\" value\n", *argv);
+		} else if (matches(*argv, "phase-seg2") == 0) {
+			NEXT_ARG();
+			if (get_u32(&bt.phase_seg2, *argv, 0))
+				invarg("invalid \"phase-seg2\" value\n", *argv);
+		} else if (matches(*argv, "sjw") == 0) {
+			NEXT_ARG();
+			if (get_u32(&bt.sjw, *argv, 0))
+				invarg("invalid \"sjw\" value\n", *argv);
+		} else if (matches(*argv, "loopback") == 0) {
+			NEXT_ARG();
+			set_ctrlmode("loopback", *argv, &cm,
+				     CAN_CTRLMODE_LOOPBACK);
+		} else if (matches(*argv, "listen-only") == 0) {
+			NEXT_ARG();
+			set_ctrlmode("listen-only", *argv, &cm,
+				     CAN_CTRLMODE_LISTENONLY);
+		} else if (matches(*argv, "triple-sampling") == 0) {
+			NEXT_ARG();
+			set_ctrlmode("triple-sampling", *argv, &cm,
+				     CAN_CTRLMODE_3_SAMPLES);
+		} else if (matches(*argv, "restart") == 0) {
+			__u32 val = 1;
+
+			addattr32(n, 1024, IFLA_CAN_RESTART, val);
+		} else if (matches(*argv, "restart-ms") == 0) {
+			__u32 val;
+
+			NEXT_ARG();
+			if (get_u32(&val, *argv, 0))
+				invarg("invalid \"restart-ms\" value\n", *argv);
+			addattr32(n, 1024, IFLA_CAN_RESTART_MS, val);
+		} else if (matches(*argv, "help") == 0) {
+			usage();
+			return -1;
+		} else {
+			fprintf(stderr, "can: what is \"%s\"?\n", *argv);
+			usage();
+			return -1;
+		}
+		argc--, argv++;
+	}
+
+	if (bt.bitrate || bt.tq)
+		addattr_l(n, 1024, IFLA_CAN_BITTIMING, &bt, sizeof(bt));
+	if (cm.mask)
+		addattr_l(n, 1024, IFLA_CAN_CTRLMODE, &cm, sizeof(cm));
+
+	return 0;
+}
+
+static const char *can_state_names[] = {
+		[CAN_STATE_ERROR_ACTIVE] = "ERROR-ACTIVE",
+		[CAN_STATE_ERROR_WARNING] = "ERROR-WARNING",
+		[CAN_STATE_ERROR_PASSIVE] = "ERROR-PASSIVE",
+		[CAN_STATE_BUS_OFF] = "BUS-OFF",
+		[CAN_STATE_STOPPED] = "STOPPED",
+		[CAN_STATE_SLEEPING] = "SLEEPING"
+};
+
+static void can_print_opt(struct link_util *lu, FILE *f, struct rtattr *tb[])
+{
+	if (!tb)
+		return;
+
+	if (tb[IFLA_CAN_CTRLMODE]) {
+		struct can_ctrlmode *cm = RTA_DATA(tb[IFLA_CAN_CTRLMODE]);
+
+		if (cm->flags)
+			print_ctrlmode(f, cm->flags);
+	}
+
+	if (tb[IFLA_CAN_STATE]) {
+		int *state = RTA_DATA(tb[IFLA_CAN_STATE]);
+
+		fprintf(f, "state %s ", *state <= CAN_STATE_MAX ?
+			can_state_names[*state] : "UNKNOWN");
+	}
+
+	if (tb[IFLA_CAN_RESTART_MS]) {
+		__u32 *restart_ms = RTA_DATA(tb[IFLA_CAN_RESTART_MS]);
+
+		fprintf(f, "restart-ms %d ", *restart_ms);
+	}
+
+	if (tb[IFLA_CAN_BITTIMING]) {
+		struct can_bittiming *bt = RTA_DATA(tb[IFLA_CAN_BITTIMING]);
+
+		fprintf(f, "\n    "
+			"bitrate %d sample-point %.3f ",
+		        bt->bitrate, (float)bt->sample_point / 1000.);
+		fprintf(f, "\n    "
+			"tq %d prop-seg %d phase-seg1 %d phase-seg2 %d sjw %d",
+			bt->tq, bt->prop_seg, bt->phase_seg1, bt->phase_seg2,
+			bt->sjw);
+	}
+
+	if (tb[IFLA_CAN_BITTIMING_CONST]) {
+		struct can_bittiming_const *btc =
+			RTA_DATA(tb[IFLA_CAN_BITTIMING_CONST]);
+
+		fprintf(f, "\n    "
+			"%s: tseg1 %d..%d tseg2 %d..%d "
+			"sjw 1..%d brp %d..%d brp-inc %d",
+		        btc->name, btc->tseg1_min, btc->tseg1_max,
+			btc->tseg2_min, btc->tseg2_max, btc->sjw_max,
+			btc->brp_min, btc->brp_max, btc->brp_inc);
+	}
+
+	if (tb[IFLA_CAN_CLOCK]) {
+		struct can_clock *clock = RTA_DATA(tb[IFLA_CAN_CLOCK]);
+
+		fprintf(f, "\n    clock %d", clock->freq);
+	}
+
+}
+
+static void can_print_xstats(struct link_util *lu,
+			     FILE *f, struct rtattr *xstats)
+{
+	struct can_device_stats *stats;
+
+	if (xstats && RTA_PAYLOAD(xstats) == sizeof(*stats)) {
+		stats = RTA_DATA(xstats);
+		fprintf(f, "\n    "
+			"re-started bus-errors arbit-lost "
+			"error-warn error-pass bus-off");
+		fprintf(f, "\n    %-10d %-10d %-10d %-10d %-10d %-10d",
+			stats->restarts, stats->bus_error,
+			stats->arbitration_lost, stats->error_warning,
+			stats->error_passive, stats->bus_off);
+	}
+}
+
+struct link_util can_link_util = {
+	.id		= "can",
+	.maxattr	= IFLA_CAN_MAX,
+	.parse_opt	= can_parse_opt,
+	.print_opt	= can_print_opt,
+	.print_xstats 	= can_print_xstats,
+};
Index: iproute2/ip/iplink.c
===================================================================
--- iproute2.orig/ip/iplink.c
+++ iproute2/ip/iplink.c
@@ -72,7 +72,7 @@ void iplink_usage(void)
 
 	if (iplink_have_newlink()) {
 		fprintf(stderr, "\n");
-		fprintf(stderr, "TYPE := { vlan | veth | vcan | dummy | ifb | macvlan }\n");
+		fprintf(stderr, "TYPE := { vlan | veth | vcan | dummy | ifb | macvlan | can }\n");
 	}
 	exit(-1);
 }
Index: iproute2/include/linux/can/netlink.h
===================================================================
--- /dev/null
+++ iproute2/include/linux/can/netlink.h
@@ -0,0 +1,113 @@
+/*
+ * linux/can/netlink.h
+ *
+ * Definitions for the CAN netlink interface
+ *
+ * Copyright (c) 2009 Wolfgang Grandegger <[email-masked]>
+ *
+ * Send feedback to <[email-masked]>
+ *
+ */
+
+#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 */