[PATCH v4 00/20] eeprom: at24: Add OF device ID table

[Rob Herring]

On Mon, May 22, 2017 at 9:23 AM, Geert Uytterhoeven
<geert at linux-m68k.org> wrote:
> Hi Javier,
>
> On Mon, May 22, 2017 at 4:01 PM, Javier Martinez Canillas
> <javier at dowhile0.org> wrote:
>> This series is a follow-up to patch [0] that added an OF device ID table
>> to the at24 EEPROM driver. As you suggested [1], this version instead of
>> adding entries for every used <vendor,device> tuple, only adds a single
>> entry for each chip type using the "atmel" vendor as a generic fallback.
>>
>> This is a re-spin that addresses some issues pointed out by Rob Herring.
>>
>> The first patch documents in the DT binding what's the correct vendor to
>> use and what are the ones that are being deprecated. The second one adds
>> the OF device ID table for the at24 driver and the next patches use this
>> vendor in the compatible string to each DTS that defines a compatible I2C
>> EEPROM device node.
>>
>> Patches can be applied independently since the DTS changes without driver
>> changes are no-op and the OF table won't be used without the DTS changes.
>>
>> [0]: https://lkml.org/lkml/2017/3/14/589
>> [1]: https://lkml.org/lkml/2017/3/15/99
>>
>> Best regards,
>> Javier
>>
>> Changes in v4:
>> - Document the manufacturers that have been deprecated (Rob Herring).
>> - Only use the atmel manufacturer in the compatible string instead of
>>   keeping the deprecated ones (Rob Herring).
>
> I think you're referring to this (https://lkml.org/lkml/2017/4/19/1136)?
>
> | > --- a/arch/arm/boot/dts/am335x-baltos.dtsi
> | > +++ b/arch/arm/boot/dts/am335x-baltos.dtsi
> | > @@ -255,7 +255,7 @@
> | >     };
> | >
> | >     at24 at 50 {
> | > -           compatible = "at24,24c02";
> | > +           compatible = "at24,24c02", "atmel,24c02";
> |
> | I think you can just drop the at24 compatibles. A new kernel doesn't
> | need it. An old kernel ignores the manufacturer. I checked that u-boot
> | only matches on "atmel,*", so okay there. Don't know about the *BSDs. I
> | couldn't find anything.
>
> I think you misunderstood what Rob means.
>
> In the case above it makes sense to drop the first compatible, as "at24" is
> not a manufacturer, but refers to ATMEL's "AT24" line of i2c FLASH ROMs.
>
> However, in cases where a real vendor/part combo is specified, like on
> r8a7791-koelsch.dts:
>
> -               compatible = "renesas,24c02";
> +               compatible = "atmel,24c02";
>
> you do want to keep the real vendor/part combo, i.e.
>
>      compatible = "renesas,24c02", "atmel,24c02";

Yes, Geert is correct.

Rob