RE: [PATCH 2/2] extcon: gpio: add DT binding doc for extcon-gpio

From: Venkat Reddy Talla
Date: Tue May 17 2016 - 07:27:16 EST


Thanks for review, please find my inline reply.

> -----Original Message-----
> From: Rob Herring [mailto:robh@xxxxxxxxxx]
> Sent: Wednesday, May 04, 2016 7:01 PM
> To: Venkat Reddy Talla
> Cc: MyungJoo Ham; Chanwoo Choi; Pawel Moll; Mark Rutland; Ian Campbell;
> Kumar Gala; linux-kernel@xxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx;
> Laxman Dewangan
> Subject: Re: [PATCH 2/2] extcon: gpio: add DT binding doc for extcon-gpio
>
> On Tue, May 03, 2016 at 11:19:51AM +0530, Venkat Reddy Talla wrote:
> > Addiing DT binding doc for the extcon gpios properties.
> >
> > Signed-off-by: Venkat Reddy Talla <vreddytalla@xxxxxxxxxx>
> > ---
> > .../devicetree/bindings/extcon/extcon-gpio.txt | 19
> +++++++++++++++++++
> > 1 file changed, 19 insertions(+)
> > create mode 100644
> > Documentation/devicetree/bindings/extcon/extcon-gpio.txt
> >
> > diff --git a/Documentation/devicetree/bindings/extcon/extcon-gpio.txt
> > b/Documentation/devicetree/bindings/extcon/extcon-gpio.txt
> > new file mode 100644
> > index 0000000..4a49c23
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/extcon/extcon-gpio.txt
> > @@ -0,0 +1,19 @@
> > +EXTCON FOR GPIO
>
> This needs a better description of what this is and what h/w this applies to.
>
I will take care in my next patch.

> > +
> > +Required Properties:
> > + - compatible : Should be "extcon-gpio";
> > +
> > +Optional Properties:
> > + - extcon-gpio,name: Name of extcon device.
> > + - gpio: gpio number.
>
> Should be 'gpios'.
>
OK, I will take care in my next patch.

> > + - extcon-gpio,irq-flags: IRQ flags for GPIO.
>
> If this is an interrupt, then you should be using the interrupts property.
>
Need to provide GPIO number instead of interrupt from DTS to read GPIO value when external connected attached/detached and also driver supports platform data with passing GPIO number.
So need to pass irq-flags using separate dts property or need to hardcode in driver.

> > + - extcon-gpio,debounce: Debounce time in ms.
>
> extcon-gpio is not a vendor prefix, so drop it.
>
> Add unit suffix (-ms).
>
OK, I will take care in my next patch.

> > + - extcon-gpio,connection-state-low: boolean, Connection state with
> > + gpio state. True if gpio low means connected.
>
> The active state should be in the GPIO flags cell.
>
OK, I will take care in my next patch.
> > +
> > +extcon-gpio {
> > + compatible = "extcon-gpio";
> > + extcon-gpio,name = "VBUS";
>
> How is VBus a gpio?
>
Here VBUS is not gpio number, VBUS is extcon device name, extcon gpio is used to detect VBUS.

> > + gpio = <&gpio 20 0>;
> > + extcon-gpio,cable-names = <EXTCON_USB EXTCON_NONE>;
>
> Not documented.
>
> Rob
OK, I will take care in my next patch.