Re: [PATCH v12 2/4] dt-bindings: power: Convert battery.txt to battery.yaml

[Rob Herring <robh@kernel.org>]

On Thu, May 28, 2020 at 05:53:48PM -0500, Ricardo Rivera-Matos wrote:
> From: Dan Murphy <dmurphy@ti.com>
> 
> Convert the battery.txt file to yaml and fix up the examples.
> 
> Signed-off-by: Dan Murphy <dmurphy@ti.com>
> ---
>  .../bindings/power/supply/battery.txt         |  82 +---------
>  .../bindings/power/supply/battery.yaml        | 143 ++++++++++++++++++
>  2 files changed, 144 insertions(+), 81 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/power/supply/battery.yaml
> 
> diff --git a/Documentation/devicetree/bindings/power/supply/battery.txt b/Documentation/devicetree/bindings/power/supply/battery.txt
> index 3049cf88bdcf..b9a81621ce59 100644
> --- a/Documentation/devicetree/bindings/power/supply/battery.txt
> +++ b/Documentation/devicetree/bindings/power/supply/battery.txt
> @@ -1,81 +1 @@
> -Battery Characteristics
> -
> -The devicetree battery node provides static battery characteristics.
> -In smart batteries, these are typically stored in non-volatile memory
> -on a fuel gauge chip. The battery node should be used where there is
> -no appropriate non-volatile memory, or it is unprogrammed/incorrect.
> -
> -Upstream dts files should not include battery nodes, unless the battery
> -represented cannot easily be replaced in the system by one of a
> -different type. This prevents unpredictable, potentially harmful,
> -behavior should a replacement that changes the battery type occur
> -without a corresponding update to the dtb.
> -
> -Required Properties:
> - - compatible: Must be "simple-battery"
> -
> -Optional Properties:
> - - voltage-min-design-microvolt: drained battery voltage
> - - voltage-max-design-microvolt: fully charged battery voltage
> - - energy-full-design-microwatt-hours: battery design energy
> - - charge-full-design-microamp-hours: battery design capacity
> - - precharge-current-microamp: current for pre-charge phase
> - - charge-term-current-microamp: current for charge termination phase
> - - constant-charge-current-max-microamp: maximum constant input current
> - - constant-charge-voltage-max-microvolt: maximum constant input voltage
> - - factory-internal-resistance-micro-ohms: battery factory internal resistance
> - - ocv-capacity-table-0: An array providing the open circuit voltage (OCV)
> -   of the battery and corresponding battery capacity percent, which is used
> -   to look up battery capacity according to current OCV value. And the open
> -   circuit voltage unit is microvolt.
> - - ocv-capacity-table-1: Same as ocv-capacity-table-0
> - ......
> - - ocv-capacity-table-n: Same as ocv-capacity-table-0
> - - ocv-capacity-celsius: An array containing the temperature in degree Celsius,
> -   for each of the battery capacity lookup table. The first temperature value
> -   specifies the OCV table 0, and the second temperature value specifies the
> -   OCV table 1, and so on.
> - - resistance-temp-table: An array providing the temperature in degree Celsius
> -   and corresponding battery internal resistance percent, which is used to look
> -   up the resistance percent according to current temperature to get a accurate
> -   batterty internal resistance in different temperatures.
> -
> -Battery properties are named, where possible, for the corresponding
> -elements in enum power_supply_property, defined in
> -https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/include/linux/power_supply.h
> -
> -Batteries must be referenced by chargers and/or fuel-gauges
> -using a phandle. The phandle's property should be named
> -"monitored-battery".
> -
> -Example:
> -
> -	bat: battery {
> -		compatible = "simple-battery";
> -		voltage-min-design-microvolt = <3200000>;
> -		voltage-max-design-microvolt = <4200000>;
> -		energy-full-design-microwatt-hours = <5290000>;
> -		charge-full-design-microamp-hours = <1430000>;
> -		precharge-current-microamp = <256000>;
> -		charge-term-current-microamp = <128000>;
> -		constant-charge-current-max-microamp = <900000>;
> -		constant-charge-voltage-max-microvolt = <4200000>;
> -		factory-internal-resistance-micro-ohms = <250000>;
> -		ocv-capacity-celsius = <(-10) 0 10>;
> -		ocv-capacity-table-0 = <4185000 100>, <4113000 95>, <4066000 90>, ...;
> -		ocv-capacity-table-1 = <4200000 100>, <4185000 95>, <4113000 90>, ...;
> -		ocv-capacity-table-2 = <4250000 100>, <4200000 95>, <4185000 90>, ...;
> -		resistance-temp-table = <20 100>, <10 90>, <0 80>, <(-10) 60>;
> -	};
> -
> -	charger: charger@11 {
> -		....
> -		monitored-battery = <&bat>;
> -		...
> -	};
> -
> -	fuel_gauge: fuel-gauge@22 {
> -		....
> -		monitored-battery = <&bat>;
> -		...
> -	};
> +The contents of this file has been moved to battery.yaml
> diff --git a/Documentation/devicetree/bindings/power/supply/battery.yaml b/Documentation/devicetree/bindings/power/supply/battery.yaml
> new file mode 100644
> index 000000000000..f0b544a22219
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/power/supply/battery.yaml
> @@ -0,0 +1,143 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/power/supply/battery.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Battery Characteristics
> +
> +maintainers:
> +  - Sebastian Reichel <sre@kernel.org> 
> +
> +description: |
> +  The devicetree battery node provides static battery characteristics.
> +  In smart batteries, these are typically stored in non-volatile memory
> +  on a fuel gauge chip. The battery node should be used where there is
> +  no appropriate non-volatile memory, or it is unprogrammed/incorrect.
> +
> +  Upstream dts files should not include battery nodes, unless the battery
> +  represented cannot easily be replaced in the system by one of a
> +  different type. This prevents unpredictable, potentially harmful,
> +  behavior should a replacement that changes the battery type occur
> +  without a corresponding update to the dtb.
> +
> +  Battery properties are named, where possible, for the corresponding elements
> +  in enum power_supply_property, defined in include/linux/power_supply.h
> +
> +  Batteries must be referenced by chargers and/or fuel-gauges using a phandle.
> +  The phandle's property should be named "monitored-battery".
> +
> +properties:
> +  compatible:
> +    const: simple-battery

I suspect we'll need a battery.yaml and simple-battery.yaml schema if 
these properties are used for other batteries. Not sure really, so fine 
for now.

> +
> +  voltage-min-design-microvolt: 
> +    $ref: /schemas/types.yaml#/definitions/uint32

Don't need types on many of these as standard units have a type already.

> +    description: drained battery voltage
> +
> +  voltage-max-design-microvolt:
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    description: fully charged battery voltage
> +
> +  energy-full-design-microwatt-hours:
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    description: battery design energy
> +
> +  charge-full-design-microamp-hours:
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    description: battery design capacity
> +
> +  precharge-current-microamp:
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    description: current for pre-charge phase
> +
> +  charge-term-current-microamp:
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    description: current for charge termination phase
> +
> +  constant-charge-current-max-microamp:
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    description: maximum constant input current
> +
> +  constant-charge-voltage-max-microvolt:
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    description: maximum constant input voltage
> +
> +  factory-internal-resistance-micro-ohms:
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    description: battery factory internal resistance
> +
> +  ocv-capacity-table-0:
> +    $ref: /schemas/types.yaml#/definitions/uint32-matrix
> +    description: |
> +      An array providing the open circuit voltage (OCV)
> +      of the battery and corresponding battery capacity percent, which is used
> +      to look up battery capacity according to current OCV value. And the open
> +      circuit voltage unit is microvolt.
> +
> +  ocv-capacity-table-1:
> +    $ref: /schemas/types.yaml#/definitions/uint32-matrix
> +    description: Same as ocv-capacity-table-0
> +
> +  ocv-capacity-table-n:
> +    $ref: /schemas/types.yaml#/definitions/uint32-matrix
> +    description: Same as ocv-capacity-table-0

Make this a pattern under patternProperties: '^ocv-capacity-table-[0-9]$' 

Is 10 enough or maybe you need more.

maxItems: 100 ?? I asssume 1% granularity would be enough for everyone?
items:
  items:
    - description: open circuit voltage (OCV) in microvolts
    - description: battery capacity percent
      maximum: 100

> +
> +  ocv-capacity-celsius:
> +    $ref: /schemas/types.yaml#/definitions/uint32-array
> +    description: |
> +      An array containing the temperature in degree Celsius,
> +      for each of the battery capacity lookup table. The first temperature value
> +      specifies the OCV table 0, and the second temperature value specifies the
> +      OCV table 1, and so on.
> +
> +  resistance-temp-table:
> +    $ref: /schemas/types.yaml#/definitions/uint32-matrix
> +    description: |
> +      An array providing the temperature in degree Celsius
> +      and corresponding battery internal resistance percent, which is used to
> +      look up the resistance percent according to current temperature to get an
> +      accurate batterty internal resistance in different temperatures.

Similar definition needed here.

> +
> +  monitored-battery:
> +    $ref: /schemas/types.yaml#/definitions/phandle
> +    description: phandle to the battery node being monitored

As this is the battery node, this property doesn't belong here.

> +
> +required:
> +  - compatible
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    power {
> +      #address-cells = <1>;
> +      #size-cells = <0>;
> +
> +      battery:battery {
> +        compatible = "simple-battery";
> +        voltage-min-design-microvolt = <3200000>;
> +        voltage-max-design-microvolt = <4200000>;
> +        energy-full-design-microwatt-hours = <5290000>;
> +        charge-full-design-microamp-hours = <1430000>;
> +        precharge-current-microamp = <256000>;
> +        charge-term-current-microamp = <128000>;
> +        constant-charge-current-max-microamp = <900000>;
> +        constant-charge-voltage-max-microvolt = <4200000>;
> +        factory-internal-resistance-micro-ohms = <250000>;
> +        ocv-capacity-celsius = <(-10) 0 10>;
> +        ocv-capacity-table-0 = <4185000 100>, <4113000 95>, <4066000 90>;
> +        ocv-capacity-table-1 = <4200000 100>, <4185000 95>, <4113000 90>;
> +        resistance-temp-table = <20 100>, <10 90>, <0 80>, <(-10) 60>;
> +      };
> +
> +      charger:charger@11 {

Drop unused labels.

> +        reg = <0x11>;
> +        monitored-battery = <&battery>;
> +      };
> +
> +      fuel_gauge:fuel-gauge@22 {
> +        reg = <0x22>;
> +        monitored-battery = <&battery>;
> +      };
> +    };
> -- 
> 2.26.2
>