Subject: Re: [PATCH] net: dsa: mv88e6xxx: Add MV88E6352 DT compatible

From: Andrew Lunn <[email-masked]>
Date: Wed, 12 Sep 2018 02:46:02 +0200

On Wed, Sep 12, 2018 at 02:04:54AM +0200, Marek Vasut wrote:
> On 09/12/2018 01:32 AM, Andrew Lunn wrote:
> >> compatible = "marvell,mv88e6352", "marvell,mv88e6085";
> > 
> > Just "marvell,mv88e6085";
> > 
> > Please take a look at all the other DT files using the Marvell
> > chips. You will only ever find "marvell,mv88e6085" or
> > "marvell,mv88e6190", because everything is compatible to one of these
> > two.
> 
> Well, until you find a difference between those chips which you cannot
> discern based solely on the ID register content. Then it's better to
> have a compatible to match on which matches the actual chip.

Hi Marek

We have been around this loop before. The problem with putting in a
more specific compatible is that nothing is validating it. So it is
going to be wrong, simple because people cut/paste, and don't
necessary change it. So when we do need to look at it, we cannot look
at it, because it is wrong.

I would only add a more specific compatible if and when we need it, it
is actually used, and we can verify it is correct.

   Andrew