[alsa-devel] driver or plugin?

hi everybody, this is my first post in the list.

currently i work in a new project, and i need is some help to finish this. I wrote an application whose take data from serial port or from bluetooth device(spp) and store the data in a raw file(the data is audio). Now i need to do this: the data received from the port, send to internet through voip software like ekiga, kphone, etc. I read writing-an-alsa-driver.pdf, alsa-driver-api.pdf but i dont know how create a source of data, for softwares of voip take data like a microphone and also receive data from these programs. I've been looking serial-u16550.c

would be something similar to what the bluez bluetooth headphones

Sorry for my english is not very good.

greetings