Re: [PATCH v2] Input: gpio_keys: Add level trigger support for GPIO keys

[Baolin Wang <baolin.wang@linaro.org>]

Hi Rob,

On 20 February 2018 at 02:11, Rob Herring <robh@kernel.org> wrote:
> On Sun, Feb 11, 2018 at 02:55:04PM +0800, Baolin Wang wrote:
>> On some platforms (such as Spreadtrum platform), the GPIO keys can only
>> be triggered by level type. So this patch introduces one property to
>> indicate if the GPIO trigger type is level trigger or edge trigger.
>
> If the parent interrupt controller only supports a certain trigger, then
> it should ignore setting the trigger type.

We still need to set high level type trigger or low level type trigger
if it only supports level trigger.

>
>>
>> Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
>> ---
>> Changes since v1:
>>  - Diable the GPIO irq until reversing the GPIO level type.
>> ---
>>  .../devicetree/bindings/input/gpio-keys.txt        |    2 ++
>>  drivers/input/keyboard/gpio_keys.c                 |   26 +++++++++++++++++++-
>>  include/linux/gpio_keys.h                          |    1 +
>>  3 files changed, 28 insertions(+), 1 deletion(-)
>>
>> diff --git a/Documentation/devicetree/bindings/input/gpio-keys.txt b/Documentation/devicetree/bindings/input/gpio-keys.txt
>> index a949404..e3104bd 100644
>> --- a/Documentation/devicetree/bindings/input/gpio-keys.txt
>> +++ b/Documentation/devicetree/bindings/input/gpio-keys.txt
>> @@ -29,6 +29,8 @@ Optional subnode-properties:
>>       - linux,can-disable: Boolean, indicates that button is connected
>>         to dedicated (not shared) interrupt which can be disabled to
>>         suppress events from the button.
>> +     - gpio-key,level-trigger: Boolean, indicates that button's interrupt
>> +       type is level trigger. Otherwise it is edge trigger as default.
>
> No. Just use 'interrupts' instead of 'gpios' and specify the trigger
> type. Or put both if you need to read the state.

Okay, so something as below to get the level type from the
'interrupts' property.
if (fwnode_property_read_u32(child, "interrupts", &button->level_type))
        button->level_type = IRQ_TYPE_NONE;

-- 
Baolin.wang
Best Regards