When read it returns all enabled interrupt sources
When written it enables interrupt sources for each bit set
So just like VIC_INT_EN_CLEAR, we don't have to read the previous value
before writing to it (VIC_INT_EN_CLEAR is write-only anyway)
Thanks to Fred Bauer for spotting
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@23734 a1c6a512-1295-4272-9138-f99709370657
registering and unregistering are handled by the non target-specific functions of timer.c
Remove arguments from the new TIMER_START since they are unused by targets
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@21553 a1c6a512-1295-4272-9138-f99709370657
