On Thu, Sep 22, 2011 at 09:42:14AM +0800, Leo Yan wrote:

On our platform, there have some devices (like hdmi/bt) do not need config from the CODEC driver, they have their own s/w stack and interface to configure; for the audio driver, just need to set the I2S/PCM timing for them. So if there have a common dummy codec driver, then it can meet our requirement well. Otherwise, there will have some duplicate codes for these dummy codecs.

The general thought here has been that for dumb CODECs the boilerplate is sufficiently small and simple to mean that the discoverability from writing a skeletal driver outweighs the cost of having it kicking around - while there is some boilerplate there it's easier for someone to grab and use this code than it is to work out how exactly to translate the datasheets into code each time they encounter the part. However, a sufficiently well written generic driver would maintain that advantage while reducing the duplication.