Re: [PATCH v4 00/17] ALSA: hda: cirrus: Add initial DSP support and firmware loading

From: Charles Keepax
Date: Mon May 30 2022 - 06:53:56 EST


On Mon, May 30, 2022 at 12:45:08PM +0200, Takashi Iwai wrote:
> On Mon, 30 May 2022 12:34:15 +0200,
> Charles Keepax wrote:
> Well, if an ALSA control can trigger the firmware loading, that's
> already fragile. A firmware loading is a heavy task, which should
> happen only at probing and/or resuming in general. Do we have other
> drivers doing the f/w loading triggered by a kctl...?
>
> > I guess we could look at adding locked versions of the add
> > control functions as well if that might be preferred?
>
> If the patterns of additional kctls (specific for firmware?) are
> fixed, we may create all such kctls beforehand and let them inactive
> unless the corresponding firmware is really loaded, too.
>

I am afraid we do, basically all the Wolfson/Cirrus audio devices
allow you to select the firmware through a kctl. The patterns of
controls are specific to the firmwares, so we can't really create
them ahead of time. One could maybe look at changing when the
firmwares are loaded, such as attempting to load all possible
firmwares on boot or something but its a fairly sizable change
that isn't without some side effects.

Thanks,
Charles