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authorDavid Howells2012-10-09 09:48:41 +0100
committerMarc Kleine-Budde2012-10-10 22:24:21 +0200
commit922cd657c95fe3e4214d68a958e98288b7a55bba (patch)
treed55095ac1cba7e4e9c715cadb932045e46bb953c /include/uapi/linux/can/gw.h
parent85457685e0e314f6902caaef976b3fd8ef4f51b4 (diff)
UAPI: (Scripted) Disintegrate include/linux/can
Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Michael Kerrisk <mtk.manpages@gmail.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: Dave Jones <davej@redhat.com> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Diffstat (limited to 'include/uapi/linux/can/gw.h')
-rw-r--r--include/uapi/linux/can/gw.h162
1 files changed, 162 insertions, 0 deletions
diff --git a/include/uapi/linux/can/gw.h b/include/uapi/linux/can/gw.h
new file mode 100644
index 000000000000..8e1db18c3cb6
--- /dev/null
+++ b/include/uapi/linux/can/gw.h
@@ -0,0 +1,162 @@
+/*
+ * linux/can/gw.h
+ *
+ * Definitions for CAN frame Gateway/Router/Bridge
+ *
+ * Author: Oliver Hartkopp <oliver.hartkopp@volkswagen.de>
+ * Copyright (c) 2011 Volkswagen Group Electronic Research
+ * All rights reserved.
+ *
+ */
+
+#ifndef CAN_GW_H
+#define CAN_GW_H
+
+#include <linux/types.h>
+#include <linux/can.h>
+
+struct rtcanmsg {
+ __u8 can_family;
+ __u8 gwtype;
+ __u16 flags;
+};
+
+/* CAN gateway types */
+enum {
+ CGW_TYPE_UNSPEC,
+ CGW_TYPE_CAN_CAN, /* CAN->CAN routing */
+ __CGW_TYPE_MAX
+};
+
+#define CGW_TYPE_MAX (__CGW_TYPE_MAX - 1)
+
+/* CAN rtnetlink attribute definitions */
+enum {
+ CGW_UNSPEC,
+ CGW_MOD_AND, /* CAN frame modification binary AND */
+ CGW_MOD_OR, /* CAN frame modification binary OR */
+ CGW_MOD_XOR, /* CAN frame modification binary XOR */
+ CGW_MOD_SET, /* CAN frame modification set alternate values */
+ CGW_CS_XOR, /* set data[] XOR checksum into data[index] */
+ CGW_CS_CRC8, /* set data[] CRC8 checksum into data[index] */
+ CGW_HANDLED, /* number of handled CAN frames */
+ CGW_DROPPED, /* number of dropped CAN frames */
+ CGW_SRC_IF, /* ifindex of source network interface */
+ CGW_DST_IF, /* ifindex of destination network interface */
+ CGW_FILTER, /* specify struct can_filter on source CAN device */
+ __CGW_MAX
+};
+
+#define CGW_MAX (__CGW_MAX - 1)
+
+#define CGW_FLAGS_CAN_ECHO 0x01
+#define CGW_FLAGS_CAN_SRC_TSTAMP 0x02
+
+#define CGW_MOD_FUNCS 4 /* AND OR XOR SET */
+
+/* CAN frame elements that are affected by curr. 3 CAN frame modifications */
+#define CGW_MOD_ID 0x01
+#define CGW_MOD_DLC 0x02
+#define CGW_MOD_DATA 0x04
+
+#define CGW_FRAME_MODS 3 /* ID DLC DATA */
+
+#define MAX_MODFUNCTIONS (CGW_MOD_FUNCS * CGW_FRAME_MODS)
+
+struct cgw_frame_mod {
+ struct can_frame cf;
+ __u8 modtype;
+} __attribute__((packed));
+
+#define CGW_MODATTR_LEN sizeof(struct cgw_frame_mod)
+
+struct cgw_csum_xor {
+ __s8 from_idx;
+ __s8 to_idx;
+ __s8 result_idx;
+ __u8 init_xor_val;
+} __attribute__((packed));
+
+struct cgw_csum_crc8 {
+ __s8 from_idx;
+ __s8 to_idx;
+ __s8 result_idx;
+ __u8 init_crc_val;
+ __u8 final_xor_val;
+ __u8 crctab[256];
+ __u8 profile;
+ __u8 profile_data[20];
+} __attribute__((packed));
+
+/* length of checksum operation parameters. idx = index in CAN frame data[] */
+#define CGW_CS_XOR_LEN sizeof(struct cgw_csum_xor)
+#define CGW_CS_CRC8_LEN sizeof(struct cgw_csum_crc8)
+
+/* CRC8 profiles (compute CRC for additional data elements - see below) */
+enum {
+ CGW_CRC8PRF_UNSPEC,
+ CGW_CRC8PRF_1U8, /* compute one additional u8 value */
+ CGW_CRC8PRF_16U8, /* u8 value table indexed by data[1] & 0xF */
+ CGW_CRC8PRF_SFFID_XOR, /* (can_id & 0xFF) ^ (can_id >> 8 & 0xFF) */
+ __CGW_CRC8PRF_MAX
+};
+
+#define CGW_CRC8PRF_MAX (__CGW_CRC8PRF_MAX - 1)
+
+/*
+ * CAN rtnetlink attribute contents in detail
+ *
+ * CGW_XXX_IF (length 4 bytes):
+ * Sets an interface index for source/destination network interfaces.
+ * For the CAN->CAN gwtype the indices of _two_ CAN interfaces are mandatory.
+ *
+ * CGW_FILTER (length 8 bytes):
+ * Sets a CAN receive filter for the gateway job specified by the
+ * struct can_filter described in include/linux/can.h
+ *
+ * CGW_MOD_XXX (length 17 bytes):
+ * Specifies a modification that's done to a received CAN frame before it is
+ * send out to the destination interface.
+ *
+ * <struct can_frame> data used as operator
+ * <u8> affected CAN frame elements
+ *
+ * CGW_CS_XOR (length 4 bytes):
+ * Set a simple XOR checksum starting with an initial value into
+ * data[result-idx] using data[start-idx] .. data[end-idx]
+ *
+ * The XOR checksum is calculated like this:
+ *
+ * xor = init_xor_val
+ *
+ * for (i = from_idx .. to_idx)
+ * xor ^= can_frame.data[i]
+ *
+ * can_frame.data[ result_idx ] = xor
+ *
+ * CGW_CS_CRC8 (length 282 bytes):
+ * Set a CRC8 value into data[result-idx] using a given 256 byte CRC8 table,
+ * a given initial value and a defined input data[start-idx] .. data[end-idx].
+ * Finally the result value is XOR'ed with the final_xor_val.
+ *
+ * The CRC8 checksum is calculated like this:
+ *
+ * crc = init_crc_val
+ *
+ * for (i = from_idx .. to_idx)
+ * crc = crctab[ crc ^ can_frame.data[i] ]
+ *
+ * can_frame.data[ result_idx ] = crc ^ final_xor_val
+ *
+ * The calculated CRC may contain additional source data elements that can be
+ * defined in the handling of 'checksum profiles' e.g. shown in AUTOSAR specs
+ * like http://www.autosar.org/download/R4.0/AUTOSAR_SWS_E2ELibrary.pdf
+ * E.g. the profile_data[] may contain additional u8 values (called DATA_IDs)
+ * that are used depending on counter values inside the CAN frame data[].
+ * So far only three profiles have been implemented for illustration.
+ *
+ * Remark: In general the attribute data is a linear buffer.
+ * Beware of sending unpacked or aligned structs!
+ */
+
+#endif