Re: [PATCH v3 2/2] drivers: misc: adi-axi-tdd: Add TDD engine

["Nuno Sá" <noname.nuno@gmail.com>]

On Mon, 2023-10-23 at 16:19 +0200, Arnd Bergmann wrote:
> On Mon, Oct 23, 2023, at 15:30, Balas, Eliza wrote:
> > > -----Original Message-----
> > > Cvetic <dragan.cvetic@amd.com>; Arnd Bergmann <arnd@arndb.de>
> > > Subject: Re: [PATCH v3 2/2] drivers: misc: adi-axi-tdd: Add TDD engine
> 
> > > > > > Since the device is not an iio device, using an iio function would
> > > > > > be confusing.
> > > > > 
> > > > > Why isn't this an iio device?
> > > > 
> > > > The device is not registered into the IIO device tree,
> > > > and does not rely on IIO kernel APIs.
> > > > Even though there are a few attributes that resemble the
> > > > ones from iio, and the sysfs structure is similar,
> > > > this is not an IIO device.
> > > > In the previous patch versions 1 and 2 we concluded
> > > > that this device fits better in the misc subsystem.
> > > 
> > > Ok, can you point to that in the changelog where the IIO maintainer
> > > agreed that this doesn't fit into that subsystem?
> > > 
> > This was one of the discussions from previous v2 : 
> > https://lore.kernel.org/all/5b6318f16799e6e2575fe541e83e42e0afebe6cf.camel@gmail.com/
> > 
> > I will add it to the changelog the next time I submit the patches.
> 
> It sounds like Jonathan wasn't quite sure either here, and I would
> still argue (as I did in that thread), that drivers/iio is probably
> a better option than drivers/misc.
> 

Well, if Jonathan agrees to have this in IIO, it would actually be better for
us... The below hack would not be needed at all and IIO is very familiar.

> In particular, you mention that you actually make this device
> appear as an IIO device to user space using the "iio-fake" hack.
> 

I want to emphasize that is just our hack to make use of libiio RPC so that we
can remotely access this device.
 
- Nuno Sá