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

[Lukasz Luba]

Hi Rob,

On 9/13/19 4:36 PM, Rob Herring wrote:
> On Fri, Sep 06, 2019 at 01:50:26PM +0200, Krzysztof Kozlowski wrote:
>> 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.
> 
> We can't have multiple (top-level) schema in one file, so better to add
> in where the existing compatible strings are.

Thank you for your comment. I will add the needed string into existing
compatible then.

Regards,
Lukasz