Re: [PATCH v2 1/2] dt-bindings: input: touchscreen: Add 'hold-in-reset-in-suspend' property to goodix

[Jan Jasper de Kroon <jajadekroon@gmail.com>]

Op 14-03-2023 om 18:47 schreef Krzysztof Kozlowski:
> On 12/03/2023 19:31, Jan Jasper de Kroon wrote:
>> This patch adds a new optional property, 'hold-in-reset-in-suspend', to the
> Do not use "This commit/patch", but imperative mood. See:
> https://elixir.bootlin.com/linux/v5.17.1/source/Documentation/process/submitting-patches.rst#L95
>
>> Goodix touchscreen device tree binding. When set to true, the touchscreen
>> controller will be held in reset mode during system suspend, reducing
>> power consumption. If not present, the property defaults to false.
>>
>> I am submitting this patch to the Device Tree mailing list to add a new
> Drop the "I am ..." Same comment as above.
>
>> property to the Goodix touchscreen device tree binding. This patch
>> supplements a related patch sent to the linux-input mailing list, which
>> updates the Goodix touchscreen driver to use this new property.
> Anyway entire paragraph does not look related to commit msg. Drop it.
>
>> The
>> linux-input patch can be found at:
>> https://lore.kernel.org/all/20230311131534.484700-1-jajadekroon@gmail.com/
> Also this. It should be rather places under ---.
>
>> Signed-off-by: Jan Jasper de Kroon <jajadekroon@gmail.com>
>> ---
>> V1 -> V2:
>> - Updated subject prefix to match subsystem
>> - Added more detailed description of the change
>> - Fixed formatting issues in commit message
>>   .../devicetree/bindings/input/touchscreen/goodix.yaml  | 10 ++++++++++
>>   1 file changed, 10 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/input/touchscreen/goodix.yaml b/Documentation/devicetree/bindings/input/touchscreen/goodix.yaml
>> index 3d016b87c8df..cd4dd3d25364 100644
>> --- a/Documentation/devicetree/bindings/input/touchscreen/goodix.yaml
>> +++ b/Documentation/devicetree/bindings/input/touchscreen/goodix.yaml
>> @@ -56,6 +56,15 @@ properties:
>>     touchscreen-size-y: true
>>     touchscreen-swapped-x-y: true
>>   
>> +  hold-in-reset-in-suspend:
> Missing vendor prefix.
>
>> +    type: boolean
>> +    default: false
> Drop default.
>
>> +    description: |
>> +      When set to true, the touchscreen controller will be held in reset mode
>> +      during system suspend. This can help reduce power consumption, but may
>> +      cause the touchscreen to take longer to resume when the system is woken
>> +      up from suspend. Defaults to false if not present.
> Drop last sentence.
>
> Anyway, the property does not look suitable for Devicetree. You describe
> system policy - trade off between energy saving and responsivness to the
> user. DT is not for policies. Use other interfaces for configuring it,
> e.g. some user-space, existing PM interfaces or /sysfs (which is ABI and
> needs its Documentation).
>
>
>> +
>>   additionalProperties: false
>>   
>>   required:
>> @@ -75,6 +84,7 @@ examples:
>>           interrupts = <0 0>;
>>           irq-gpios = <&gpio1 0 0>;
>>           reset-gpios = <&gpio1 1 0>;
>> +        hold-in-reset-in-suspend;
>>         };
>>       };
>>   
> Best regards,
> Krzysztof
>
I think the latest patch covers most of the feedback you provided.
Regarding the addition of this feature to the DeviceTree. Currently this
is only used on the Linux powered PinePhone Original and PinePhone Pro. It
also isn't really a policy change, but rather an attempt to minimize
battery consumption on these power hungry devices. Developers made a lot
of tweaks here and there, to make the PinePhone get through a day of light
use. This is one of these tweaks.

Best regards,
Jan Jasper de Kroon