[PATCH v4 05/20] dt-bindings: memory: factorise LPDDR props into SDRAM props

[Julius Werner]

> > I don't think this will identify a part unambiguously, I would expect
> > the DDR revision ID to be specific to the part number. (In fact, we're
> > also not sure whether manufacturer+revision identifies LPDDR parts
> > unambiguously for every vendor, we just didn't have anything more to
> > work with there.) I would suggest to use either `ddrX-YYYY,AAA...,ZZ`
> > or `ddrX-YYYY,ZZ,AAA...` (where AAA... is the part number string from
> > SPD 329-348 without the trailing spaces). The first version looks a
> > bit more natural but it might get confusing on the off chance that
> > someone uses a comma in a part number string.
>
> The first one seems better indeed.
> If the manufacturer put a comma in the part number we should handle it
> at a software level to me and if it is a devicetree error it is up to
> the devicetree writer to fix it.
> What do you think ?

Not sure what you mean by "handle it at a software level"? Using comma
characters in the part number is not illegal according to the SPD
spec, as far as I can tell.

That said, it is still possible to disambiguate this as long as the
revision number is always there, you just have to look for the last
comma from the end (so e.g. the string `ddr4-1234,some,part,567,89`
could be unambiguously parsed as manufacturer ID 0x1234, part number
`some,part,567` and revision ID 0x89, the parsing code just needs to
be a bit careful). So maybe this is not actually a problem.