[Qemu-devel] Re: Audio output for CS4231, patch/RFC

[malc]

Blue Swirl <blueswir1 <at> hotmail.com> writes:

> 
> Hi,
> 
> This patch hooks CS4231 to the audio subsystem. It's not ready for applying, 
> though I can already make some noise. Any comments?

After having a cursory look at it only one thing really caught my attention:
in the audio callback you set s->audio_free to the provided value, but then
in you never use it. If i'm reading everything correctly this would lead to
reading N bytes from DMA in write_audio, succeeding in writing only M bytes
(where M < N) to the audio subsystem and loosing N-M bytes forever. Basically
you should never attempt to do volatile reads of more than audio_free bytes.
SB16 operates in similar fashion.