[Pxc] pxc development

[Alessandro Rubini]

I'm working on the pxc driver (well, I've been for a few days, but I
can't devote full-time to a single project).

I'm adding support for a list of buffers. A process can get hold of a
buffer and no DMA will be performed on that buffer before it releases
the buffer.  If DMA is continuously running and you asked for at least
three buffers, a program can always release a buffer an immediately
access the most recent frame (buffer) with no delay at all.

Things are being massively restructured and will be overall
simplified. I'm also adding proper locking for SMP operation and other
goodies (like select() etc).

However, I plant to drop support for version 2.0 of the kernel, for a
few reasons (I have problems in testing it twice, I can use
generalized lists that are not there in 2.0, I can implement poll and
not select).

Is there some use of the pxc driver that needs 2.0 support and some
feature that is not yet present in the current versions? If so, I
think I'll split the source tree and port back those needed features
to the 2.0 source tree; given my strict schedule the next version will
most likely be 2.2 only (and 2.4 in a near future).

Thanks for your feedback
/alessandro