Re: [PATCH v4 05/10] dt-bindings: gpio: Add gpio nodes for Actions S900 SoC

[Manivannan Sadhasivam]

Hi Rob,

Thanks for the review.

On Wed, Mar 07, 2018 at 01:52:33PM -0600, Rob Herring wrote:
> On Fri, Mar 02, 2018 at 09:20:40AM +0530, Manivannan Sadhasivam wrote:
> > Add gpio nodes for Actions Semi S900 SoC.
> > 
> > Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
> > ---
> >  .../devicetree/bindings/gpio/actions,owl-gpio.txt  | 95 ++++++++++++++++++++++
> >  1 file changed, 95 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/gpio/actions,owl-gpio.txt
> > 
> > diff --git a/Documentation/devicetree/bindings/gpio/actions,owl-gpio.txt b/Documentation/devicetree/bindings/gpio/actions,owl-gpio.txt
> > new file mode 100644
> > index 000000000000..d2939ca6cfaf
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/gpio/actions,owl-gpio.txt
> > @@ -0,0 +1,95 @@
> > +* Actions Semi OWL GPIO controller bindings
> > +
> > +The GPIOs are organized as individual banks/ports with variable number
> > +of GPIOs. Each bank is represented as an individual GPIO controller.
> > +
> > +Required properties:
> > +- compatible            : Should be "actions,s900-gpio"
> > +- reg                   : Address and range of the GPIO controller registers.
> > +- gpio-controller       : Marks the device node as a GPIO controller.
> > +- #gpio-cells           : Should be <2>. The first cell is the gpio number
> > +                          and the second cell is used to specify optional
> > +                          parameters.
> > +- interrupt-controller  : Marks the device node as an interrupt controller.
> > +- #interrupt-cells      : Specifies the number of cells needed to encode an
> > +                          interrupt.  Shall be set to 2.  The first cell
> > +                          defines the interrupt number, the second encodes
> > +                          the trigger flags described in
> > +                          bindings/interrupt-controller/interrupts.txt
> > +
> > +Optional properties:
> > +- gpio-ranges           : Mapping between GPIO and pinctrl
> > +
> > +Note: Each GPIO port should have an alias correctly numbered in "aliases"
> > +node.
> 
> Why? Please don't use aliases for gpios.
> 

Okay.

> > +
> > +Examples:
> > +
> > +aliases {
> > +        gpio0 = &gpioa;
> > +        gpio1 = &gpiob;
> > +        gpio2 = &gpioc;
> > +        gpio3 = &gpiod;
> > +        gpio4 = &gpioe;
> > +        gpio5 = &gpiof;
> > +};
> > +
> > +       gpioa: gpioa@e01b0000 {
> 
> Use generic node names (gpio).
>

Okay. But how about the label? Should it be gpioa... or gpio1...
In datasheet, the registers are named from gpioa to gpiof.
 
> > +               compatible = "actions,s900-gpio";
> > +               reg = <0x0 0xe01b0000 0x0 0x1000>;
> > +               gpio-controller;
> > +               #gpio-cells = <2>;
> > +               gpio-ranges = <&pinctrl 0 0 32>;
> > +               interrupt-controller;
> > +               #interrupt-cells = <2>;
> > +       };
> > +
> > +       gpiob: gpiob@e01b0000 {
> 
> Ah, but your are duplicating addresses here which you shouldn't do 
> either. These should be all one node if you can avoid overlapping.
>

Hmmm. Okay. Then I can use the sub address for all nodes. But having a single
node doesn't makes sense here since each bank has its own interrupt
domain and somewhat resembles an individual controller.

Thanks,
Mani

> > +               compatible = "actions,s900-gpio";
> > +               reg = <0x0 0xe01b0000 0x0 0x1000>;
> > +               gpio-controller;
> > +               #gpio-cells = <2>;
> > +               gpio-ranges = <&pinctrl 0 32 32>;
> > +               interrupt-controller;
> > +               #interrupt-cells = <2>;
> > +       };
> > +
> > +       gpioc: gpioc@e01b0000 {
> > +               compatible = "actions,s900-gpio";
> > +               reg = <0x0 0xe01b0000 0x0 0x1000>;
> > +               gpio-controller;
> > +               #gpio-cells = <2>;
> > +               gpio-ranges = <&pinctrl 0 64 12>;
> > +               interrupt-controller;
> > +               #interrupt-cells = <2>;
> > +       };
> > +
> > +       gpiod: gpiod@e01b0000 {
> > +               compatible = "actions,s900-gpio";
> > +               reg = <0x0 0xe01b0000 0x0 0x1000>;
> > +               gpio-controller;
> > +               #gpio-cells = <2>;
> > +               gpio-ranges = <&pinctrl 0 76 30>;
> > +               interrupt-controller;
> > +               #interrupt-cells = <2>;
> > +       };
> > +
> > +       gpioe: gpioe@e01b0000 {
> > +               compatible = "actions,s900-gpio";
> > +               reg = <0x0 0xe01b0000 0x0 0x1000>;
> > +               gpio-controller;
> > +               #gpio-cells = <2>;
> > +               gpio-ranges = <&pinctrl 0 106 32>;
> > +               interrupt-controller;
> > +               #interrupt-cells = <2>;
> > +       };
> > +
> > +       gpiof: gpiof@e01b0000 {
> > +               compatible = "actions,s900-gpio";
> > +               reg = <0x0 0xe01b0000 0x0 0x1000>;
> > +               gpio-controller;
> > +               #gpio-cells = <2>;
> > +               gpio-ranges = <&pinctrl 0 138 8>;
> > +               interrupt-controller;
> > +               #interrupt-cells = <2>;
> > +       };
> > -- 
> > 2.14.1
> >