Re: [PATCH v3] net: wan: framer: Add version sysfs attribute for the Lantiq PEF2256 framer

From: Jakub Kicinski

Date: Fri Sep 26 2025 - 16:35:24 EST


On Thu, 25 Sep 2025 09:06:13 +0200 Christophe Leroy wrote:
> Le 25/09/2025 à 01:48, Jakub Kicinski a écrit :
> > On Wed, 24 Sep 2025 17:06:47 +0200 Christophe Leroy wrote:
> >> Lantiq PEF2256 framer has some little differences in behaviour
> >> depending on its version.
> >>
> >> Add a sysfs attribute to allow user applications to know the
> >> version.
> >
> > Outsider question perhaps but what is the version of?
> > It sounds like a HW revision but point releases for ASICs are quite
> > uncommon. So I suspect it's some SW/FW version?
>
> The datasheet of the component just calls it 'version'.
>
> Among all registers there is a register called 'version status register'
> which contains a single field named 'Version Number of chip'. This field
> is an 8 bits value and the documentation tells that value 0x00 is
> version 1.2, value 0x10 is version 2.1, etc...
>
> > We generally recommend using devlink dev info for reporting all sort
> > of versions...
>
> Ok, I'll look at devlink. Based on the above, what type of
> DEVLINK_INFO_VERSION_GENERIC_XXXX would you use here ?

That all sounds very mysterious. Maybe let's stick with sysfs if
we don't really know the details and where to put the value..