I have been experimenting with the RaspberryPi. In particular I wanted to get a webcam working with the Debian “squeeze” distro available on the Raspberry Pi downloads page.

The original Debian squeeze img contains a kernel that does not have v4l2 configured. However the latest firmware for the Raspberry Pi does include a recompiled kernel with v4l2 support added.

There is a tool for updating the Raspberry Pi firmware – however a bit of cajoling was required to get it to work.

$ sudo apt-get install ca-certificates
$ sudo apt-get install git-core
$ sudo wget http://goo.gl/1BOfJ -O /usr/bin/rpi-update
$ sudo chmod +x /usr/bin/rpi-update
$ sudo rpi-update
Raspberry Pi firmware updater by Hexxeh, enhanced by AndrewS
Performing self-update
Autodetecting memory split
Using ARM/GPU memory split of 192MB/64MB
We're running for the first time
Setting up firmware (this will take a few minutes)
Using SoftFP libraries
/opt/vc/sbin/vcfiled: error while loading shared libraries: libvchiq_arm.so: cannot open shared object file: No such file or directory
If no errors appeared, your firmware was successfully setup
A reboot is needed to activate the new firmware

The first time I tried this I ignored the error and rebooted only to get a black screen and the Raspberry Pi’s “red light of fail”.

So I set up a fresh image and started again.
This time I added a couple of extra steps

$ sudo rpi-update
Raspberry Pi firmware updater by Hexxeh, enhanced by AndrewS
Performing self-update
Autodetecting memory split
Using ARM/GPU memory split of 192MB/64MB
We're running for the first time
Setting up firmware (this will take a few minutes)
Using SoftFP libraries
/opt/vc/sbin/vcfiled: error while loading shared libraries: libvchiq_arm.so: cannot open shared object file: No such file or directory
If no errors appeared, your firmware was successfully setup
A reboot is needed to activate the new firmware
$ sudo ldconfig
$ sudo rpi-update
Raspberry Pi firmware updater by Hexxeh, enhanced by AndrewS
Performing self-update
Autodetecting memory split
Using ARM/GPU memory split of 192MB/64MB
Updating firmware (this will take a few minutes)
Your firmware is already up to date
$ sudo reboot

By running

$ sudo ldconfig
$ sudo rpi-update

After the first failure, the rpi-update completes and reboot is successful.

On reboot running

$ ls /dev/

shows that /dev/video0 is now available.