On Sun, May 10, 2015 at 08:33:20PM +0100, Russell King - ARM Linux wrote:
My personal view is that where we're dealing with PCM audio, the driver needs to set these bits correctly as there is nothing in userspace to do this. This provides an identical interface between each audio device which accepts PCM samples - whether it's a SPDIF or non-SPDIF based device.
For non-audio data sent via an audio device, the AES bits need to be conveyed from userspace, and we should respect what userspace gives us. (If it's wrong, it's a userspace bug, and userspace should be fixed, rather than trying to work around the bug by patching the kernel.)
For what it's worth this is exactly what I'd be expecting to happen - the kernel should do something by default and then let applications override it if they so desire.