Re: [PATCH 3/3] dt-bindings: ddr: Add bindings for Samsung LPDDR3 memories

From: Krzysztof Kozlowski
Date: Fri Sep 06 2019 - 07:50:43 EST


On Fri, 6 Sep 2019 at 13:39, Lukasz Luba <l.luba@xxxxxxxxxxxxxxxxxxx> wrote:
>
> Hi Krzysztof,
>
> On 9/6/19 12:56 PM, Krzysztof Kozlowski wrote:
> > On Fri, 6 Sep 2019 at 12:14, Lukasz Luba <l.luba@xxxxxxxxxxxxxxxxxxx> wrote:
> >>
> >> Add description of bindings for Samsung k3qf2f20db LPDDR3 memory.
> >> Minor fixes in the old documentation.
> >>
> >> Signed-off-by: Lukasz Luba <l.luba@xxxxxxxxxxxxxxxxxxx>
> >> ---
> >> .../devicetree/bindings/ddr/lpddr3.txt | 29 +++++++++++++++++--
> >> 1 file changed, 27 insertions(+), 2 deletions(-)
> >>
> >> diff --git a/Documentation/devicetree/bindings/ddr/lpddr3.txt b/Documentation/devicetree/bindings/ddr/lpddr3.txt
> >> index 3b2485b84b3f..de0905239767 100644
> >> --- a/Documentation/devicetree/bindings/ddr/lpddr3.txt
> >> +++ b/Documentation/devicetree/bindings/ddr/lpddr3.txt
> >> @@ -40,10 +40,34 @@ Child nodes:
> >> a given speed-bin. Please see Documentation/devicetree/
> >> bindings/ddr/lpddr3-timings.txt for more information on "lpddr3-timings"
> >>
> >> +Samsung K3QF2F20DB LPDDR3 memory
> >> +------------------------------------------------------------
> >> +
> >> +This binding uses the LPDDR3 binding (described above)
> >> +
> >> +Required properties:
> >> +- compatible: Should be:
> >> + "samsung,K3QF2F20DB"
> >> + followed by "jedec,lpddr3"
> >> +- density : <u32> representing density in Mb (Mega bits)
> >> +- io-width : <u32> representing bus width. Possible value 32
> >> +- #address-cells: Must be set to 1
> >> +- #size-cells: Must be set to 0
> >
> > If you decided to repeat all properties again, then it deserves its
> > own bindings file. However I though about simpler solution - just
> > document compatible. Exactly the same as AT24 or AT25 EEPROM bindings.
> > There is not much benefit from copying all these properties.
> OK, I see. I will add only 'compatible' and skip the rest then.
> So the lpddr3.txt file will get this addition:
>
> +Samsung K3QF2F20DB LPDDR3 memory
> +------------------------------------------------------------
> +
> +This binding uses the LPDDR3 binding (described above)
> +
> +Required properties:
> +- compatible: Should be:
> + "samsung,K3QF2F20DB"
> + followed by "jedec,lpddr3"
> +
> +Optional properties:
> +
> +The optional properties are the same as in the LPDDR3 generic bindings and
> +values should be taken from the data-sheet. Detailed bindings are described
> +above.
> +
> +Child nodes:
> +
> +Detailed bindings are described in LPDDR3 generic bindings described above.
> +
>
> Is it OK?

To me it is still a lot of text just for one compatible and I can
image more of such entries for other memories... However I do not mind
and anyway, YAML will simplify it. If you're in doubt, wait for Rob's
reply as this is his part.

Best regards,
Krzysztof