
*_init():

each subdev should init fields:
	type
	n_chan
	subdev_flags
	maxdata || maxdata_list
	flags || flag_list
	range_type || range_type_list
	trig

    (optional)
	timer_type
	len_chanlist
	maxbufsz
	cancel


check subdev_flags, RT, etc.

check for mem leaks

check that each synchronous function returns 1

check that comedi_done is eventually called.

