On Do, 2014-09-04 at 00:22 -0700, Harry Cruise wrote: > Hello, > > > I am trying to comprehend QEMU AUDIO backend functionality and need to > implementing device which has few audio channels from which it > receives audio streams (sampled at some specific frequency), and > further process that data stream like mixing two stream. > > > I am new for the QEMU, Please help me in following queries: > > > 1) Please suggest some document and example/device implement which has > use qemu audio backend.
hw/usb/dev-audio.c (implementing usb speaker emulation) is probably the best sample code for that. > 3) What steps I need to add into device to setup audio support as per > the requirement I mentioned above ? You can just create multiple streams. AUD_open_* returns a handle so you can disturgist them. > 4) what is the basic working flow of audio backend and accessing audio > streams using dma ? Nothing special for audio here, they do dma like any other device. You don't see that in hw/usb/dev-audio.c though as DMA is handled elsewhere (uhci/ehci/xhci usb host adapter emulation). You might want to look at intel-hda for pci dma sample code. HTH, Gerd
