Re: [PATCH] ARM: dts: am437x-gp-evm: Add wakeup interrupt source for pixcir_i2c_ts

From: Vignesh R
Date: Wed Oct 14 2015 - 07:38:34 EST




On 10/14/2015 04:34 PM, Roger Quadros wrote:
> Vignesh,
>
> On 14/10/15 12:12, Vignesh R wrote:
>>
>>
>> On 10/14/2015 02:16 PM, Roger Quadros wrote:
>>
>>>
>>> On 14/10/15 08:52, Vignesh R wrote:
>>>> On am437x-gp-evm, pixcir_i2c_ts can wakeup the system from lower power
>>>> state via pinctrl and IO daisy chain using generic wakeirq framework.
>>>> With commit 3fffd1283927 ("i2c: allow specifying separate wakeup
>>>> interrupt in device tree") i2c core allows optional wakeirq to be
>>>> specified via device tree. Add wakeup irq entry to enable pixcir_i2c_ts
>>>> to wake the system from low power state.
>>>>
>>>> Signed-off-by: Vignesh R <vigneshr@xxxxxx>
>>>> ---
>>>> arch/arm/boot/dts/am437x-gp-evm.dts | 5 +++++
>>>> 1 file changed, 5 insertions(+)
>>>>
>>>> diff --git a/arch/arm/boot/dts/am437x-gp-evm.dts b/arch/arm/boot/dts/am437x-gp-evm.dts
>>>> index 22038f21f228..69e93af7df0d 100644
>>>> --- a/arch/arm/boot/dts/am437x-gp-evm.dts
>>>> +++ b/arch/arm/boot/dts/am437x-gp-evm.dts
>>>> @@ -581,8 +581,13 @@
>>>>
>>>> attb-gpio = <&gpio3 22 GPIO_ACTIVE_HIGH>;
>>>>
>>>> + interrupts-extended = <&gpio3 22 GPIO_ACTIVE_HIGH>,
>>>> + <&am43xx_pinmux 0x264>;
>>>
>>> How does this work?
>>>
>>> interrupts-extended property must have
>>> 1) interrupt parent
>>> 2) interrupt number
>>> 3) interrupt flags
>>>
>>> Your change doesn't seem to comply with those requirements.
>>
>> AFAIU, interrupts-extended has two parts: interrupt parent phandle and
>> interrupt specifier.
>> The number of cells in interrupt specifier is determined by
>> interrupt-cells property of interrupt parent node.
>
> Got it.
>
>> In above case, gpio3 has interrupt-cells = 2 hence interrupt specifier
>> has interrupt number and interrupt flag field.
>
> But is GPIO_ACTIVE_HIGH an interrupt flag?

Oops.. I will change it to IRQ_TYPE_NONE as represented in interrupts
property.

>
>> But in case am43xx_pinmux node, interrupt-cells is 1 hence has no
>> interrupt flag field.
>>
> Understood, thanks. Might be worth adding a comment as to what 0x264 means though.
>

Will add a one line comment indicating its the offset of gpio3_22
padconf register from am43xx_pinmux base.

> cheers,
> -roger
>

--
Regards
Vignesh
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