I recently found that you can fix the hotplug problem (When you connect a USB device to the computer it doesn't activate automatically, you have to reboot), when using linux on HP Pavilion dv6220la.
In a previous post I wrote you have to add some flags to the linux kernel when you boot the computer. These flags are:
The problem comes with noapic. It seems to disable hotplug. To fix this, you just need to add another flag:
So the final flags are:
noapic nolapic irqfixup
If you dont want to edit directly the /boot/grub/menu.lst you can download the package qgrubeditor. You can find it within Synaptics. It comes with a nice GUI to edit grub.