Re: Persistent module storage [was Linux 2.4 Status / TODO page]

Oliver Xymoron
2000-11-06T19:10:02Z

On Mon, 6 Nov 2000, Jeff Garzik wrote:

> Oliver Xymoron wrote:
> >
> > On Mon, 6 Nov 2000, David Woodhouse wrote:
> >
> > > The point here is that although I've put up with just keeping the sound
> > > driver loaded for the last few years, permanently taking up a large amount
> > > of DMA memory, the inter_module_xxx stuff that Keith is proposing would
> > > give us a simple way of storing the data which we want to store.
> > ...
> > > Being able to do it completely in userspace would be neater, though.
> >
> > I think there are a bunch of other devices that need stuff from userspace
> > before they fully init, namely the ones that load proprietary firmware
> > images. Will an approach like that work here?
>
> Some devices have a firmware.h that is compiled into the driver. A few
> sound devices use a function that loads a firmware file from userspace,
> given a filename. The comment in drivers/sound/sound_firmware.c says
> that this is a poor method, and that the recommended method for
> uploading firmware to a device is via ioctl.

Ioctl (or alternate device for plan9 groupies) is fine. My point is final
initialization of the device is obviously delayed until the firmware is
loaded. Adopting a similar strategy for initializing mixers (possibly
falling back to initializing with zero levels) minimizes the window
between resetting a device and having sane mixer settings.

--
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