Re: [PATCH] Input: atmel_mxt_ts - add missing compatible strings to OF device table

[Rob Herring]

On Tue, May 1, 2018 at 1:48 PM, Dmitry Torokhov
<dmitry.torokhov@xxxxxxxxx> wrote:
> On Tue, Apr 10, 2018 at 11:53:40AM +0200, Javier Martinez Canillas wrote:
>> Commit af503716ac14 ("i2c: core: report OF style module alias for devices
>> registered via OF") fixed how the I2C core reports the module alias when
>> devices are registered via OF.
>>
>> But the atmel_mxt_ts driver only has an "atmel,maxtouch" compatible in its
>> OF device ID table, so if a Device Tree is using a different one, autoload
>> won't be working for the module (the matching works because the I2C device
>> ID table is used as a fallback).
>>
>> So add compatible strings for each of the entries in the I2C device table.
>>
>> Fixes: af503716ac14 ("i2c: core: report OF style module alias for devices registered via OF")
>> Reported-by: Enric Balletbo i Serra <enric.balletbo@xxxxxxxxxxxxx>
>> Signed-off-by: Javier Martinez Canillas <javierm@xxxxxxxxxx>
>> ---
>>
>>  Documentation/devicetree/bindings/input/atmel,maxtouch.txt | 6 +++++-
>>  drivers/input/touchscreen/atmel_mxt_ts.c                   | 4 ++++
>>  2 files changed, 9 insertions(+), 1 deletion(-)
>>
>> diff --git a/Documentation/devicetree/bindings/input/atmel,maxtouch.txt b/Documentation/devicetree/bindings/input/atmel,maxtouch.txt
>> index 23e3abc3fdef..cd43fb8bc2ce 100644
>> --- a/Documentation/devicetree/bindings/input/atmel,maxtouch.txt
>> +++ b/Documentation/devicetree/bindings/input/atmel,maxtouch.txt
>> @@ -1,8 +1,12 @@
>>  Atmel maXTouch touchscreen/touchpad
>>
>>  Required properties:
>> -- compatible:
>> +- compatible: Must be one of the following
>> +    atmel,qt602240_ts
>> +    atmel,atmel_mxt_ts
>> +    atmel,atmel_mxt_tp
>>      atmel,maxtouch
>> +    atmel,mXT224
>
> I do not think we should document ad-hoc compatible strings that were
> introduced by various vendors as the documented ones, so I'd rather
> dropped this chunk and leave only "atmel,maxtouch" as compatible that
> everyone should be using.
>
> The changes to the driver to support the existing DTSes can of course be
> applied.
>
> Rob, any objections?

I'd prefer we list them in the binding as deprecated. Then we document
somewhere besides this thread to not use them.

And there are 3 dts changes needed as well:

$ git grep atmel,mXT224
$ git grep atmel,qt6
$ git grep atmel,atmel_mxt
arch/arm/boot/dts/at91-sama5d4ek.dts:
 compatible = "atmel,atmel_mxt_ts";
arch/arm64/boot/dts/rockchip/rk3399-gru-kevin.dts:
compatible = "atmel,atmel_mxt_tp";
arch/arm64/boot/dts/rockchip/rk3399-gru-kevin.dts:
compatible = "atmel,atmel_mxt_ts";

Rob