Re: [PATCH 1/6] mfd: Add Delta TN48M CPLD driver

[Lee Jones]

On Wed, 19 May 2021, Michael Walle wrote:

> Hi,
> 
> Am 2021-05-19 13:53, schrieb Robert Marko:
> > On Thu, May 6, 2021 at 6:34 PM Michael Walle <michael@xxxxxxxx> wrote:
> > > Am 2021-04-30 14:35, schrieb Robert Marko:
> > > > Delta TN48M switches have a Lattice CPLD that serves
> > > > multiple purposes including being a GPIO expander.
> > > > So lets add the MFD core driver for it.
> > > 
> > > Did you have a look at mfd/simple-mfd-i2c.c?
> > 
> > Yes, that was my first idea but we have a requirement to expose CPLD
> > information via debugfs as there are userspace applications using it.
> > And simple-mfd-i2c does not allow us to do so.
> 
> Mh, last time Lee wasn't very fond of having a driver that just populates
> sub-drivers while doing almost nothing itself. See
> https://lore.kernel.org/lkml/20200605065709.GD3714@dell/

Right.  I still feel that way.

> That being said, I'd also like to expose our CPLD version, but until now
> haven't found a good solution.

Why though?  Does S/W *need* it?

-- 
Lee Jones [李琼斯]
Senior Technical Lead - Developer Services
Linaro.org │ Open source software for Arm SoCs
Follow Linaro: Facebook | Twitter | Blog