Re: [PATCH 1/2] extcon: usb-gpio: Add level trigger support

From: Baolin Wang
Date: Wed May 03 2017 - 06:56:53 EST


Hi Rob,

On 29 March 2017 at 14:08, Baolin Wang <baolin.wang@xxxxxxxxxx> wrote:
> Hi,
>
> On 24 March 2017 at 20:41, Rob Herring <robh+dt@xxxxxxxxxx> wrote:
>> On Fri, Mar 24, 2017 at 6:56 AM, Baolin Wang <baolin.wang@xxxxxxxxxx> wrote:
>>> Hi,
>>>
>>> On 24 March 2017 at 19:08, Chanwoo Choi <cw00.choi@xxxxxxxxxxx> wrote:
>>>> Hi,
>>>>
>>>> On 2017ë 03ì 20ì 16:59, Baolin Wang wrote:
>>>>> Now extcon-usb-gpio only supports for GPIO egdge trigger, but VBUS/ID
>>>>> gpios' detection can be triggered by the level trigger on some platforms.
>>>>> Thus intoduce one property 'extcon-gpio,level-trigger' to identify this
>>>>> situation.
>>>>>
>>>>> Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxx>
>>>>> ---
>>>>> .../devicetree/bindings/extcon/extcon-usb-gpio.txt | 3 +++
>>>>> 1 file changed, 3 insertions(+)
>>>>>
>>>>> diff --git a/Documentation/devicetree/bindings/extcon/extcon-usb-gpio.txt b/Documentation/devicetree/bindings/extcon/extcon-usb-gpio.txt
>>>>> index dfc14f7..191504b 100644
>>>>> --- a/Documentation/devicetree/bindings/extcon/extcon-usb-gpio.txt
>>>>> +++ b/Documentation/devicetree/bindings/extcon/extcon-usb-gpio.txt
>>>>> @@ -9,6 +9,9 @@ Required properties:
>>>>> Either one of id-gpio or vbus-gpio must be present. Both can be present as well.
>>>>> - id-gpio: gpio for USB ID pin. See gpio binding.
>>>>> - vbus-gpio: gpio for USB VBUS pin.
>>>>> +- extcon-gpio,level-trigger: Boolean, set this gpio's interrupt flag to
>>>>
>>>> It is 'extcon-usb-gpio' instead of 'extcon-gpio'.
>>>
>>> Sure.
>>
>> "extcon-gpio" is not a vendor, so don't make it a vendor prefix.
>
> OK.
>
>>
>>>>> +level trigger. If not specified defaults to false, gpio's interrupt flag
>>>>> +defaults to edge trigger.
>>>>
>>>> I understand why you need the new flag.
>>>> But, I'm not sure it is right way to add the new flag for interrupt flag.
>>>>
>>>> IMHO, I think that we need to find the more proper way to get the interrupt flag
>>>> or maybe, we may need to implement the new helper api to get the interrupt
>>>> flag for gpio pin when we use the gpio as the interrupt source,
>>>
>>> Yes, I agree with you. We already have helper functions to get
>>> interrupt flag from device tree, but we can not get the irq number of
>>> GPIO to configure in device tree, then I introduce one new flag to
>>> indicate the trigger type. But I like to change the patch if there are
>>> any good suggestion. Thanks.
>>
>> The extcon binding needs an overhaul in general. I'm not going to take
>> extensions to a broken binding. What's needed is a USB connector
>> binding like we have for HDMI and other video connectors. And for
>> USB-C, those need to be combined.

Could you elaborate on how to make an overhaul for the extcon binding?
I can help to do that and then we can consider to modify my patch.
Thanks.

>
> I am not sure I understand your points correctly, could you elaborate
> on how to modify for extcon? Thanks.
>
> --
> Baolin.wang
> Best Regards



--
Baolin.wang
Best Regards