On Fri, 21 May 2010, Ralf Baechle wrote: > > particular in: > > sound/oss/swarm_cs4297a.c > > This one is specific to the Swarm, a MIPS-based platform indeed; I'll cc > Maciej Rozycki who most likely is the only person on the planet knowing the > technical details. I don't even recall touching that file so my (C) > header in there is a surprise :) You probably added a missing header inclusion or suchlike. ;) That's a Crystal Sound CS4297A AC'97 codec wired to a synchronous serial interface of the SWARM board. It used to work with 2.4 after some tweaks I did back then (it broke in the little-endian mode or something like that), but I can't say anything about 2.6. I think the driver should be dropped and the serial port in the sound mode (there's a demux to switch the interface's external connection between the codec and a DE-9 connector; the serial port supports asynchronous mode as well) properly abstracted as a "sound card". There's a separate CS4297A driver already in our tree, so it should be used in place of the codec bits from this driver (which I believe were simply copied over at some point). The rest is glue logic to set up serial line parameters correctly for the codec and switch the demux to the codec (no proper resource management is done for that though; the selection used to be made at the kernel build time). This glue logic is all that's needed to be carried over to the new "sound card" driver. I have plans to do so in some indefinite future, probably when I retire and my grandchildren have grown up; anyone please feel free to take it first. ;) Maciej