[alsa-devel] No device for DAI %s

[Patrick Doyle]

Hello all,
In snd_soc_register_dai() there is a warning message generated:

	/* The device should become mandatory over time */
	if (!dai->dev)
		printk(KERN_WARNING "No device for DAI %s\n", dai->name);

I am curious -- what is the intent of that warning message?  If the
device "should become mandatory over time" when will that happen
(obviously, when the developer of a particular device makes it
happen), but what would motivate the developer to do so?  If I am that
developer, and I am adapting code from another device, what do I need
to do (and why should I do it) to associate a device with a DAI?

Actually, in a more general sense, is there any good
article/book/tutorial/blog explaining the design and architecture of
the SoC code in ALSA?  Right now, I am in a maze of little twisty
passages, all alike, composed of calls to snd_soc_register_dai(),
platform_register_driver(), platform_register_device, "soc-audio"
platform drivers, i2s drivers, i2c drivers, etc... and would like to
find something to help me pull my head back above water.  (Have I
mixed enough metaphors here?)

Thanks for any tips folks can give.

--wpd