Re: [PATCH V2] Input: pm8941-pwrkey: add resin key capabilities

[Bjorn Andersson <bjorn.andersson@linaro.org>]

On Tue 13 Mar 01:35 PDT 2018, Tirupathi Reddy wrote:

> Add resin key support to handle different types of key events
> defined in different platforms.
> 
> Signed-off-by: Tirupathi Reddy <tirupath@codeaurora.org>
> ---
>  .../bindings/input/qcom,pm8941-pwrkey.txt          | 20 ++++++-
>  drivers/input/misc/pm8941-pwrkey.c                 | 65 +++++++++++++++++++++-
>  2 files changed, 83 insertions(+), 2 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/input/qcom,pm8941-pwrkey.txt b/Documentation/devicetree/bindings/input/qcom,pm8941-pwrkey.txt
> index 07bf55f..f499cf8 100644
> --- a/Documentation/devicetree/bindings/input/qcom,pm8941-pwrkey.txt
> +++ b/Documentation/devicetree/bindings/input/qcom,pm8941-pwrkey.txt
> @@ -20,6 +20,14 @@ PROPERTIES
>  		    defined by the binding document describing the node's
>  		    interrupt parent.
>  
> +- interrupt-names:
> +	Usage: required
> +	Value type: <stringlist>
> +	Definition: Interrupt names.  This list must match up 1-to-1 with the
> +		    interrupts specified in the 'interrupts' property. "kpdpwr"
> +		    must be specified and should be the first entry of the list.
> +		    "resin" may be specified for some platforms.
> +
>  - debounce:
>  	Usage: optional
>  	Value type: <u32>
> @@ -32,12 +40,22 @@ PROPERTIES
>  	Definition: presence of this property indicates that the KPDPWR_N pin
>  		    should be configured for pull up.
>  
> +- linux,code:
> +	Usage: required for "resin" key
> +	Value type: <u32>
> +	Definition: The input key-code associated with the resin key.
> +		    Use the linux event codes defined in
> +		    include/dt-bindings/input/linux-event-codes.h

For completeness sake I think this should list both the key code for the
power key and for the RESIN key.

> +
>  EXAMPLE
>  
>  	pwrkey@800 {
>  		compatible = "qcom,pm8941-pwrkey";
>  		reg = <0x800>;
> -		interrupts = <0x0 0x8 0 IRQ_TYPE_EDGE_BOTH>;
> +		interrupts = <0x0 0x8 0 IRQ_TYPE_EDGE_BOTH>,
> +			     <0x0 0x8 1 IRQ_TYPE_EDGE_BOTH>;
> +		interrupt-names = "kpdpwr", "resin";
>  		debounce = <15625>;
>  		bias-pull-up;

Do we need to support defining the bias for the resin as well?

Perhaps it makes more sense to describe the RESIN key with a separate
compatible and define that in a node of its own (we can still implement
this in the same driver - if there's any chance of reuse...).

> +		linux,code = <KEY_VOLUMEDOWN>;
>  	};
> diff --git a/drivers/input/misc/pm8941-pwrkey.c b/drivers/input/misc/pm8941-pwrkey.c
> index 18ad956..2fffc7c 100644
> --- a/drivers/input/misc/pm8941-pwrkey.c
> +++ b/drivers/input/misc/pm8941-pwrkey.c
> @@ -28,6 +28,7 @@
>  
>  #define PON_RT_STS			0x10
>  #define  PON_KPDPWR_N_SET		BIT(0)
> +#define  PON_RESIN_N_SET		BIT(1)
>  
>  #define PON_PS_HOLD_RST_CTL		0x5a
>  #define PON_PS_HOLD_RST_CTL2		0x5b
> @@ -46,6 +47,7 @@
>  struct pm8941_pwrkey {
>  	struct device *dev;
>  	int irq;
> +	u32 resin_key_code;
>  	u32 baseaddr;
>  	struct regmap *regmap;
>  	struct input_dev *input;
> @@ -130,6 +132,24 @@ static irqreturn_t pm8941_pwrkey_irq(int irq, void *_data)
>  	return IRQ_HANDLED;
>  }
>  
> +static irqreturn_t pm8941_resinkey_irq(int irq, void *_data)
> +{
> +	struct pm8941_pwrkey *pwrkey = _data;
> +	unsigned int sts;
> +	int error;
> +
> +	error = regmap_read(pwrkey->regmap,
> +			    pwrkey->baseaddr + PON_RT_STS, &sts);

This needs to be broken because the line is 81 chars long, if you use a
shorter name for the return value (e.g. "ret") you don't need to do
this.

> +	if (error)
> +		return IRQ_HANDLED;
> +
> +	input_report_key(pwrkey->input, pwrkey->resin_key_code,
> +			 !!(sts & PON_RESIN_N_SET));

Put pwrkey->resin_key_code in a local variable named "key" (or even
key_code) and you don't need to line wrap this one.

> +	input_sync(pwrkey->input);
> +
> +	return IRQ_HANDLED;
> +}
> +

Regards,
Bjorn