Re: [PATCH 1/4] dt-bindings: net: dsa: nxp,sja1105: Add reset-gpios property

[Rob Herring <robh@kernel.org>]

On Wed, Sep 10, 2025 at 06:55:18PM +0200, Marco Felsch wrote:
> On 25-09-10, Vladimir Oltean wrote:
> > On Wed, Sep 10, 2025 at 05:53:59PM +0200, Marco Felsch wrote:
> > > IMHO silently removing the support will break designs for sure and
> > > should never be done. As said, imagine that the firmware will handle the
> > > supplies and the driver only needs to release the reset. If you silently
> > > remove the support, the device will be kept in reset-state. In field
> > > firmware updates are seldom, so you break your device by updating to a
> > > new kernel.
> > > 
> > > One could argue that the driver supported it but there was no dt-binding
> > > yet, so it was a hidden/unstable feature but I don't know the policy.
> > 
> > Ok, I didn't think about, or meet, the case where Linux is required by
> > previous boot stages to deassert the reset. It is the first time you are
> > explicitly saying this, though.
> > 
> > So we can keep and document the 'reset-gpios' support, but we need to
> > explicitly point out that if present, it does not supplant the need to
> > ensure the proper POR sequence as per AH1704.
> 
> We could do that but I think that no one should assume that the driver
> ensures this due to the missing power-supply and clock support. But this
> goes to the DT maintainers. IMHO we shouldn't mention any document
> within the binding, maybe within the commit message, since those
> documents may get removed.

We probably have lots of dead links... So what's one more possible one. 
If the information is useful, then I'd put the link there.

Rob