Re: [PATCH 05/14] dt-bindings: gpio: Convert Broadcom STB GPIO to YAML

[Gregory Fong <gregory.0xf0@xxxxxxxxx>]

Hi Florian,

I haven't kept up with the new yaml format, so not entirely sure I
know what I'm talking about yet, but here are a few comments:

On Wed, Dec 1, 2021 at 12:51 PM Florian Fainelli <f.fainelli@xxxxxxxxx> wrote:
>
> Convert the Broadcom STB GPIO Device Tree binding to YAML to help with
> validation.
>
> Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
> ---
>  .../bindings/gpio/brcm,brcmstb-gpio.txt       |  83 --------------
>  .../bindings/gpio/brcm,brcmstb-gpio.yaml      | 104 ++++++++++++++++++
>  MAINTAINERS                                   |   2 +-
>  3 files changed, 105 insertions(+), 84 deletions(-)
>  delete mode 100644 Documentation/devicetree/bindings/gpio/brcm,brcmstb-gpio.txt
>  create mode 100644 Documentation/devicetree/bindings/gpio/brcm,brcmstb-gpio.yaml
>
> diff --git a/Documentation/devicetree/bindings/gpio/brcm,brcmstb-gpio.txt b/Documentation/devicetree/bindings/gpio/brcm,brcmstb-gpio.txt
> deleted file mode 100644
> index 5d468ecd1809..000000000000
> --- a/Documentation/devicetree/bindings/gpio/brcm,brcmstb-gpio.txt
> +++ /dev/null
> @@ -1,83 +0,0 @@
> [snip]
> -
> -- interrupts-extended:
> -    Alternate form of specifying interrupts and parents that allows for
> -    multiple parents.  This takes precedence over 'interrupts' and
> -    'interrupt-parent'.  Wakeup-capable GPIO controllers often route their
> -    wakeup interrupt lines through a different interrupt controller than the
> -    primary interrupt line, making this property necessary.

It looks like interrupts-extended was removed from the new docs, I'm
assuming that was intentional?

> [snip]
> diff --git a/Documentation/devicetree/bindings/gpio/brcm,brcmstb-gpio.yaml b/Documentation/devicetree/bindings/gpio/brcm,brcmstb-gpio.yaml
> new file mode 100644
> index 000000000000..4b7309dc74dc
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/gpio/brcm,brcmstb-gpio.yaml
> @@ -0,0 +1,104 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/gpio/brcm,brcmstb-gpio.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Broadcom STB "UPG GIO" GPIO controller
> +
> +description: >
> +  The controller's registers are organized as sets of eight 32-bit
> +  registers with each set controlling a bank of up to 32 pins.  A single
> +  interrupt is shared for all of the banks handled by the controller.
> +
> +maintainers:
> +  - Doug Berger <opendmb@xxxxxxxxx>
> +  - Florian Fainelli <f.fainelli@xxxxxxxxx>
> +
> +properties:
> +  compatible:
> +    oneOf:
> +      - items:
> +          - enum:
> +              - brcm,bcm7445-gpio
> +          - const: brcm,brcmstb-gpio
> +
> +  reg:
> +    maxItems: 1
> +    description:

Missing folded block scalar marker ('>') above

> +      Define the base and range of the I/O address space containing
> +      the brcmstb GPIO controller registers
> +
> +  "#gpio-cells":
> +    const: 2
> +    description: >
> +      The first cell is the pin number (within the controller's
> +      pin space), and the second is used for the following:
> +      bit[0]: polarity (0 for active-high, 1 for active-low)
> +
> +  gpio-controller: true
> +
> +  "brcm,gpio-bank-widths":
> +    $ref: /schemas/types.yaml#/definitions/uint32-array
> +    description:

Same here

> +      Number of GPIO lines for each bank.  Number of elements must
> +      correspond to number of banks suggested by the 'reg' property.
> +
> +  interrupts:
> +    maxItems: 1
> +    description:

While it's not necessary while this is only one line, consider adding
'>' here too.

> +      The interrupt shared by all GPIO lines for this controller.
> +
> +  "#interrupt-cells":
> +    const: 2
> +    description: >

This next block could get formatted strangely with '>'; recommend
using '|' instead

> +      The first cell is the GPIO number, the second should specify
> +      flags.  The following subset of flags is supported:
> +      - bits[3:0] trigger type and level flags
> +        1 = low-to-high edge triggered
> +        2 = high-to-low edge triggered
> +        4 = active high level-sensitive
> +        8 = active low level-sensitive
> +      Valid combinations are 1, 2, 3, 4, 8.
> +
> +  interrupt-controller: true
> +
> +  wakeup-source:
> +    type: boolean
> +    description: >
> +      GPIOs for this controller can be used as a wakeup source
> +
> +required:
> +  - compatible
> +  - reg
> +  - gpio-controller
> +  - "#gpio-cells"

Need to add required property "brcm,gpio-bank-widths"

> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    upg_gio: gpio@f040a700 {
> +        #gpio-cells = <2>;
> +        #interrupt-cells = <2>;
> +        compatible = "brcm,bcm7445-gpio", "brcm,brcmstb-gpio";
> +        gpio-controller;
> +        interrupt-controller;
> +        reg = <0xf040a700 0x80>;
> +        interrupt-parent = <&irq0_intc>;
> +        interrupts = <0x6>;
> +        brcm,gpio-bank-widths = <32 32 32 24>;
> +    };
> +
> +    upg_gio_aon: gpio@f04172c0 {
> +        #gpio-cells = <2>;
> +        #interrupt-cells = <2>;
> +        compatible = "brcm,bcm7445-gpio", "brcm,brcmstb-gpio";
> +        gpio-controller;
> +        interrupt-controller;
> +        reg = <0xf04172c0 0x40>;
> +        interrupt-parent = <&irq0_aon_intc>;
> +        interrupts = <0x6>;
> +        wakeup-source;
> +        brcm,gpio-bank-widths = <18 4>;
> +    };
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 913856599623..78161abc384f 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -3772,7 +3772,7 @@ BROADCOM BRCMSTB GPIO DRIVER
>  M:     Gregory Fong <gregory.0xf0@xxxxxxxxx>

Not really related to this patch, but I should probably update this
entry to reflect current reality. Should that be you and/or Doug?

>  L:     bcm-kernel-feedback-list@xxxxxxxxxxxx
>  S:     Supported
> -F:     Documentation/devicetree/bindings/gpio/brcm,brcmstb-gpio.txt
> +F:     Documentation/devicetree/bindings/gpio/brcm,brcmstb-gpio.yaml
>  F:     drivers/gpio/gpio-brcmstb.c
>
>  BROADCOM BRCMSTB I2C DRIVER
> --
> 2.25.1
>

Best regards,
Gregory