From mboxrd@z Thu Jan  1 00:00:00 1970
From: nm@ti.com (Nishanth Menon)
Date: Tue, 19 Aug 2014 05:23:35 -0500
Subject: [PATCH 1/2] doc: dt/bindings: input: introduce palmas power button
 description
In-Reply-To: <20140819052842.GB21199@core.coreip.homeip.net>
References: <1408392810-16011-1-git-send-email-nm@ti.com>
 <1408392810-16011-2-git-send-email-nm@ti.com>
 <20140819052842.GB21199@core.coreip.homeip.net>
Message-ID: <53F325A7.4020806@ti.com>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On 08/19/2014 12:28 AM, Dmitry Torokhov wrote:
> On Mon, Aug 18, 2014 at 03:13:29PM -0500, Nishanth Menon wrote:
>> Many palmas family of PMICs have support for interrupt based power
>> button. This allows the device to notify the processor of external
>> push button events over the shared palmas interrupt.
>>
>> Document the hardware support for the same.
>>
>> Signed-off-by: Nishanth Menon <nm@ti.com>
>> ---
>>   .../bindings/input/ti,palmas-pwrbutton.txt         |   32 ++++++++++++++++++++
>>   1 file changed, 32 insertions(+)
>>   create mode 100644 Documentation/devicetree/bindings/input/ti,palmas-pwrbutton.txt
>>
>> diff --git a/Documentation/devicetree/bindings/input/ti,palmas-pwrbutton.txt b/Documentation/devicetree/bindings/input/ti,palmas-pwrbutton.txt
>> new file mode 100644
>> index 0000000..6a89bcd
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/input/ti,palmas-pwrbutton.txt
>> @@ -0,0 +1,32 @@
>> +Texas Instruments Palmas family power button module
>> +
>> +This module is part of the Palmas family of PMICs. For more details
>> +about the whole chip see:
>> +Documentation/devicetree/bindings/mfd/palmas.txt.
>> +
>> +This module provides a simple power button event via an Interrupt.
>> +
>> +Required properties:
>> +- compatible: should be one of the following
>> +   - "ti,palmas-pwrbutton": For Palmas compatible power on button
>> +- interrupt-parent: Parent interrupt device, must be handle of palmas node.
>> +- interrupts: Interrupt number of power button submodule on device.
>> +
>> +Optional Properties:
>> +
>> +- ti,palmas-long-press-seconds: Duration in seconds which the power
>> +  button should be kept pressed for Palmas to power off automatically.
>> +  NOTE: This depends on OTP support and POWERHOLD signal configuration
>> +  on platform.
>
> Only a few values are valid for this property, I think you should mention that.

Agreed. Will do so.
>
>> +
>> +Example:
>> +
>> +&palmas {
>> +	palmas_pwr_button: pwrbutton {
>> +		compatible = "ti,palmas-pwrbutton";
>> +		interrupt-parent = <&tps659038>;
>> +		interrupts = <1 IRQ_TYPE_NONE>;
>
> Why none? Can we specify appropriate trigger here instead of hard-coding in the
> driver?

Following the convention as in 
Documentation/devicetree/bindings/mfd/palmas.txt - for whatever reason 
we went with interrupt-cells = <2> when palmas interrupt configuration 
was hardcoded in the chip(not reconfigurable). I believe it was level, 
will check and update the example here.
>
>> +		wakeup-source;
>
> What handles this attribute? I do not see it handled in the driver.

we dont explicitly need to in the driver, it was meant to indicate that 
this is a wakeup source, but in reality, it is a palmas PMIC which is 
the wakeup source.. so, will drop this.

>
>> +		ti,palmas-long-press-seconds = <12>;
>> +	};
>> +};
>> --
>> 1.7.9.5
>>
>
> Thanks.
>