Linux drivers development

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This page summarizes all you need to know before starting to develop Linux drivers for your Armadeus board

Recommended reading before starting

We advise you to read (not necessarly understand ;-) ):

Adding your own drivers

Our custom drivers build is integrated to the Linux build system (kbuild). You can select, in the linux "menuconfig / xconfig" tool, which Armadeus drivers you want to add on your target.

 $ make linux-menuconfig
Device Drivers  --->
    Armadeus specific drivers  --->

Here is the way to add custom drivers:

  • change current dir to your armadeus view
  • in target/linux/modules/, add a directory for your driver (ex toto/)
  • put reference to this directory in the target/linux/modules/Makefile and target/linux/modules/Kconfig files
  • in toto/ put your driver source code and create 2 files, Kconfig and Makefile. (Use target/linux/modules/gpio/Makefile & Kconfig as examples.)

To compile all the custom modules, either launch:

 $ make -C target/linux/modules/


 $ make linux

Only make linux will install the modules in the target rootfs image

i.MX register access from driver

To access i.MX registers from your driver, please use the readw/readl/writew/writel helper functions. Take a look at at arch/arm/mach-mx2/apf27.c or arch/arm/mach-imx/apf9328.c to have examples.


  • Activate debug messages (from pr_debug() function) on console:
 # echo 8 > /proc/sys/kernel/printk

Useful Links