I have a DCR-TRV20. It works w/o problems in my gentoo using IEEE1394. It works with the driver from the kernel as long as you configure it:
# IEEE 1394 (FireWire) support
#
CONFIG_IEEE1394=y
#
# Subsystem Options
#
# CONFIG_IEEE1394_VERBOSEDEBUG is not set
# CONFIG_IEEE1394_OUI_DB is not set
# CONFIG_IEEE1394_EXTRA_CONFIG_ROMS is not set
# CONFIG_IEEE1394_EXPORT_FULL_API is not set
#
# Device Drivers
#
# CONFIG_IEEE1394_PCILYNX is not set
CONFIG_IEEE1394_OHCI1394=y
There are many guides online, one very good to do capture, editing and burn would be:
http://www.kinodv.org/, w/ this and the correct driver you can even watch in real time your movie while it is being transfered from your mini DV to your hard drive.
hope this helps, even if just a little bit. Good luck.