CAN bus Linux driver

From ArmadeusWiki
Revision as of 15:48, 18 April 2011 by KevinJ (Talk | contribs) (→‎Driver installation)

Jump to: navigation, search

The current CAN bus driver uses SocketCAN API which is now the official CAN API for Linux. SocketCAN is based on the Linux socket. Further details can be found on the links at the bottom of this page.

Warning Warning: Please ensure that you use the trunk version of armadeus (kernel linux-2.6.38.1 is required) before trying the instructions described on this page!


Driver installation

 $ make linux26-menuconfig

Networking support  --->
    <M>   CAN bus subsystem support ---> 
        --- CAN bus subsystem support
        <M>   Raw CAN Protocol (raw access with CAN-ID filtering)
        <M>   Broadcast Manager CAN Protocol (with content filtering)
              CAN Device Drivers  --->
                  <M> Virtual Local CAN Interface (vcan)
                  <M> Platform CAN drivers with Netlink support
                  [*]   CAN bit-timing calculation   
                  <M> Microchip 251x series SPI CAN Controller

 $ make linux26
 $ make
  • Reflash kernel and rootfs

Usage

  • Load all the needed drivers:
modprobe can
modprobe can-dev
modprobe can-raw 
modprobe mcp251x
  • Set the bitrate before all operations

Example: Set the bitrate of the can interface can0 on 125kbps 

ip link set can0 up type can bitrate 125000

Quick test

Once the driver installed and the bitrate is set, the CAN interface has to be started like a standard net interface 

 # ifconfig can0 up

and can be stopped like that: 

 # ifconfig can0 down

The socketCAN version can be retrieved like that: 

 # cat /proc/net/can/version

The socketCAN statistics can be retrieved like that: 

 # cat /proc/net/can/stats

Userspace tools

  • Several tools are provided by socketCAN:
    • candump: dump traffic on a CAN network
    • cansend: simple command line tool to send CAN-frames via CAN_RAW sockets
    • cangen: CAN frames generator for testing purpose
    • canplayer: send CAN frames from a file to a CAN interface
  • These tools can be compiled and installed on the target by means of the Buildroot menuconfig:
$ make menuconfig

Package Selection for the target  --->
    Networking  --->
        [*]   Socket CAN

$ make

then, reflash your rootfs.

Links

Retrieved from "http://armadeus.org/wiki/index.php?title=CAN_bus_Linux_driver&oldid=9544"