[CAN]: Add broadcast manager (bcm) protocol

This patch adds the CAN broadcast manager (bcm) protocol.

Signed-off-by: Oliver Hartkopp <[email protected]>
Signed-off-by: Urs Thuermann <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

Author: Oliver Hartkopp

include/linux/can/bcm.h

@@ -0,0 +1,65 @@
+/*
+ * linux/can/bcm.h
+ *
+ * Definitions for CAN Broadcast Manager (BCM)
+ *
+ * Author: Oliver Hartkopp <[email protected]>
+ * Copyright (c) 2002-2007 Volkswagen Group Electronic Research
+ * All rights reserved.
+ *
+ * Send feedback to <[email protected]>
+ *
+ */
+
+#ifndef CAN_BCM_H
+#define CAN_BCM_H
+
+/**
+ * struct bcm_msg_head - head of messages to/from the broadcast manager
+ * @opcode:    opcode, see enum below.
+ * @flags:     special flags, see below.
+ * @count:     number of frames to send before changing interval.
+ * @ival1:     interval for the first @count frames.
+ * @ival2:     interval for the following frames.
+ * @can_id:    CAN ID of frames to be sent or received.
+ * @nframes:   number of frames appended to the message head.
+ * @frames:    array of CAN frames.
+ */
+struct bcm_msg_head {
+	int opcode;
+	int flags;
+	int count;
+	struct timeval ival1, ival2;
+	canid_t can_id;
+	int nframes;
+	struct can_frame frames[0];
+};
+
+enum {
+	TX_SETUP = 1,	/* create (cyclic) transmission task */
+	TX_DELETE,	/* remove (cyclic) transmission task */
+	TX_READ,	/* read properties of (cyclic) transmission task */
+	TX_SEND,	/* send one CAN frame */
+	RX_SETUP,	/* create RX content filter subscription */
+	RX_DELETE,	/* remove RX content filter subscription */
+	RX_READ,	/* read properties of RX content filter subscription */
+	TX_STATUS,	/* reply to TX_READ request */
+	TX_EXPIRED,	/* notification on performed transmissions (count=0) */
+	RX_STATUS,	/* reply to RX_READ request */
+	RX_TIMEOUT,	/* cyclic message is absent */
+	RX_CHANGED	/* updated CAN frame (detected content change) */
+};
+
+#define SETTIMER            0x0001
+#define STARTTIMER          0x0002
+#define TX_COUNTEVT         0x0004
+#define TX_ANNOUNCE         0x0008
+#define TX_CP_CAN_ID        0x0010
+#define RX_FILTER_ID        0x0020
+#define RX_CHECK_DLC        0x0040
+#define RX_NO_AUTOTIMER     0x0080
+#define RX_ANNOUNCE_RESUME  0x0100
+#define TX_RESET_MULTI_IDX  0x0200
+#define RX_RTR_FRAME        0x0400
+
+#endif /* CAN_BCM_H */

net/can/Kconfig

@@ -26,3 +26,16 @@ config CAN_RAW
 	  most cases where no higher level protocol is being used. The raw
 	  socket has several filter options e.g. ID masking / error frames.
 	  To receive/send raw CAN messages, use AF_CAN with protocol CAN_RAW.
+
+config CAN_BCM
+	tristate "Broadcast Manager CAN Protocol (with content filtering)"
+	depends on CAN
+	default N
+	---help---
+	  The Broadcast Manager offers content filtering, timeout monitoring,
+	  sending of RTR frames, and cyclic CAN messages without permanent user
+	  interaction. The BCM can be 'programmed' via the BSD socket API and
+	  informs you on demand e.g. only on content updates / timeouts.
+	  You probably want to use the bcm socket in most cases where cyclic
+	  CAN messages are used on the bus (e.g. in automotive environments).
+	  To use the Broadcast Manager, use AF_CAN with protocol CAN_BCM.

net/can/Makefile

@@ -7,3 +7,6 @@ can-objs		:= af_can.o proc.o
 
 obj-$(CONFIG_CAN_RAW)	+= can-raw.o
 can-raw-objs		:= raw.o
+
+obj-$(CONFIG_CAN_BCM)	+= can-bcm.o
+can-bcm-objs		:= bcm.o