Hi,
I am looking for ways to download audio calibration data to a co-processor under ALSA framework. I would like to know if there is already a precedent which handles this use case. I considered request_firmware() approach but there are few drawbacks to this approach. The audio calibration data size can be substantial as number of audio use cases grows. It also requires co-processor perform extensive parsing of data. Furthermore, host processor and co-processor need to establish common use case definitions so co-processor know what chunk of calibration data to apply in certain scenario such as device switch.
If there is no precedent, my idea is to apply calibration data through sysfs. After introduction of ASoC multi-component architecture, PCM stream created from dailink is registered as device. So, there is syfs entry for each dailink. If ALSA ASoC can provide API for drivers(platform/CPU) to register additional attributes to the PCM device, this approach gives user-space application the ability to push down new calibration as audio situation changes. I believe it's a viable solution to my problem and perhaps can be useful to other systems as well.
Your feedback is appreciated.
Thanks Patrick