Re: [PATCH v1 1/6] dt_bindings: mfd: Add ROHM BD9576MUF and BD9573MUF PMICs

[Rob Herring <robh@kernel.org>]

On Thu, Sep 17, 2020 at 11:01:52AM +0300, Matti Vaittinen wrote:
> Add bindings for ROHM BD9576MUF and BD9573MUF PMICs. These
> PMICs are primarily intended to be used to power the R-Car series
> processors. They provide 6 power outputs, safety features and a
> watchdog with two functional modes.
> 
> Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
> ---
>  .../bindings/mfd/rohm,bd9576-pmic.yaml        | 129 ++++++++++++++++++
>  1 file changed, 129 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/mfd/rohm,bd9576-pmic.yaml
> 
> diff --git a/Documentation/devicetree/bindings/mfd/rohm,bd9576-pmic.yaml b/Documentation/devicetree/bindings/mfd/rohm,bd9576-pmic.yaml
> new file mode 100644
> index 000000000000..f17d4d621585
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mfd/rohm,bd9576-pmic.yaml
> @@ -0,0 +1,129 @@
> +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/mfd/rohm,bd9576-pmic.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: ROHM BD9576MUF and BD9573MUF Power Management Integrated Circuit bindings
> +
> +maintainers:
> +  - Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
> +
> +description: |
> +  BD9576MUF and BD9573MUF are power management ICs primarily intended for
> +  powering the R-Car series processors.
> +  The IC provides 6 power outputs with configurable sequencing and safety
> +  monitoring. A watchdog logic with slow ping/windowed modes is also included.
> +
> +properties:
> +  compatible:
> +    enum:
> +      - rohm,bd9576
> +      - rohm,bd9573
> +
> +  reg:
> +    description:
> +      I2C slave address.
> +    maxItems: 1
> +
> +  interrupts:
> +    maxItems: 1
> +
> +  rohm,vout1-en-low:
> +    description:
> +      BD9576 and BD9573 VOUT1 regulator enable state can be individually
> +      controlled by a GPIO. This is dictated by state of vout1-en pin during
> +      the PMIC startup. If vout1-en is LOW during PMIC startup then the VOUT1
> +      enable sate is controlled via this pin. Set this property if vout1-en
> +      is wired to be down at PMIC start-up.
> +    type: boolean
> +
> +  rohm,vout1-en-gpios:
> +    description:
> +      GPIO specifier to specify the GPIO connected to vout1-en for vout1 ON/OFF
> +      state control.
> +    maxItems: 1
> +
> +  rohm,ddr-sel-low:
> +    description:
> +      The BD9576 and BD9573 output voltage for DDR can be selected by setting
> +      the ddr-sel pin low or high. Set this property if ddr-sel is grounded.
> +    type: boolean
> +
> +  rohm,watchdog-enable-gpios:
> +    description: The GPIO line used to enable the watchdog.
> +    maxItems: 1
> +
> +  rohm,watchdog-ping-gpios:
> +    description: The GPIO line used to ping the watchdog.
> +    maxItems: 1
> +
> +  hw_margin_ms:

Needs a vendor prefix.

s/_/-/

> +    minimum: 4
> +    maximum: 4416
> +    description: Watchog timeout in milliseconds

Maybe the words in the description should be in the property name as 
I don't see how 'h/w margin' relates to 'watchdog timeout'.

Is this a max and below is the min?:

> +
> +  rohm,hw-margin-min-ms:
> +    minimum: 2
> +    maximum: 220
> +    description:
> +      Watchdog on these ICs can be configured in a window mode where the ping
> +      must come within certain time-window. Eg. too quick pinging will also
> +      trigger timeout. Specify the minimum delay between pings if you wish to
> +      use the window mode. Note, the maximum delay is internally configured as
> +      a certain multiple of this value so maximum delay can be only up to 15
> +      times this value. For example for 73 ms short ping value the maximum
> +      timeout will be close to 1 sec.
> +
> +  regulators:
> +    $ref: ../regulator/rohm,bd9576-regulator.yaml
> +    description:
> +      List of child nodes that specify the regulators.
> +
> +required:
> +  - compatible
> +  - reg
> +  - regulators
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/gpio/gpio.h>
> +    #include <dt-bindings/leds/common.h>
> +    i2c {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +        pmic: pmic@30 {
> +            compatible = "rohm,bd9576";
> +            reg = <0x30>;
> +            rohm,vout1-en-low;
> +            rohm,vout1-en-gpios = <&gpio2 6 GPIO_ACTIVE_HIGH>;
> +            rohm,ddr-sel-low;
> +            rohm,watchdog-enable-gpios = <&gpio2 6 GPIO_ACTIVE_HIGH>;
> +            rohm,watchdog-ping-gpios = <&gpio2 7 GPIO_ACTIVE_HIGH>;
> +            hw_margin_ms = <30>;
> +            rohm,hw-margin-min-ms = <4>;
> +
> +            regulators {
> +                boost1: regulator-vd50 {
> +                    regulator-name = "VD50";
> +                };
> +                buck1: regulator-vd18 {
> +                    regulator-name = "VD18";
> +                };
> +                buck2: regulator-vdddr {
> +                    regulator-name = "vdddr";
> +                };
> +                buck3: regulator-vd10 {
> +                    regulator-name = "vd10";
> +                };
> +                ldo: regulator-voutl1 {
> +                    regulator-name = "VOUTL1";
> +                };
> +                sw: regulator-vouts1 {
> +                    regulator-name = "VOUTS1";
> +                };
> +            };
> +        };
> +    };
> -- 
> 2.21.0
> 
> 
> -- 
> Matti Vaittinen, Linux device drivers
> ROHM Semiconductors, Finland SWDC
> Kiviharjunlenkki 1E
> 90220 OULU
> FINLAND
> 
> ~~~ "I don't think so," said Rene Descartes. Just then he vanished ~~~
> Simon says - in Latin please.
> ~~~ "non cogito me" dixit Rene Descarte, deinde evanescavit ~~~
> Thanks to Simon Glass for the translation =]