[PATCH v9 2/3] dt-bindings: hwmon: Support Aspeed g6 PWM TACH Control

Billy Tsai billy_tsai at aspeedtech.com
Wed Oct 4 18:26:45 PDT 2023


>> Document the compatible for aspeed,ast2600-pwm-tach device, which can
>> support up to 16 PWM outputs and 16 fan tach input.
>>
>> Signed-off-by: Billy Tsai <billy_tsai at aspeedtech.com>
>> ---
>>  .../bindings/hwmon/aspeed,g6-pwm-tach.yaml    | 69 +++++++++++++++++++
>>  1 file changed, 69 insertions(+)
>>  create mode 100644 Documentation/devicetree/bindings/hwmon/aspeed,g6-pwm-tach.yaml
>>
>> diff --git a/Documentation/devicetree/bindings/hwmon/aspeed,g6-pwm-tach.yaml b/Documentation/devicetree/>bindings/hwmon/aspeed,g6-pwm-tach.yaml
>> new file mode 100644
>> index 000000000000..5a679f4ad2fa
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/hwmon/aspeed,g6-pwm-tach.yaml
>> @@ -0,0 +1,69 @@
>> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
>> +# Copyright (C) 2023 Aspeed, Inc.
>> +%YAML 1.2
>> +---
>> +$id: http://devicetree.org/schemas/hwmon/aspeed,g6-pwm-tach.yaml#
>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>> +
>> +title: ASPEED G6 PWM and Fan Tach controller device driver

> This is binding for the h/w, not a 'device driver'.

Okay, I will remove the 'device driver'.

>> +
>> +maintainers:
>> +  - Billy Tsai <billy_tsai at aspeedtech.com>
>> +
>> +description: |
>> +  The ASPEED PWM controller can support up to 16 PWM outputs.
>> +  The ASPEED Fan Tacho controller can support up to 16 fan tach input.
>> +  They are independent hardware blocks, which are different from the
>> +  previous version of the ASPEED chip.
>> +
>> +properties:
>> +  compatible:
>> +    enum:
>> +      - aspeed,ast2600-pwm-tach
>> +
>> +  reg:
>> +    maxItems: 1
>> +
>> +  clocks:
>> +    maxItems: 1
>> +
>> +  resets:
>> +    maxItems: 1
>> +
>> +  "#pwm-cells":
>> +    const: 3
>> +
>> +patternProperties:
>> +  "^fan-[0-9a-f]+$":

> foo-<index> naming is decimal, not hex. (unit-addresses are hex)

Okay, I will change it to the decimal.

> But if 0 and 1 correspond to something in the h/w, then you should
> probably be using 'reg' instead (which means a unit-address too).

The number doesn't unrelate to the hardware.

>> +    $ref: fan-common.yaml#
>> +    unevaluatedProperties: false
>> +    required:
>> +      - tach-ch
>> +
>> +required:
>> +  - reg
>> +  - clocks
>> +  - resets
>> +  - "#pwm-cells"
>> +  - compatible
>> +
>> +additionalProperties: false
>> +
>> +examples:
>> +  - |
>> +    #include <dt-bindings/clock/aspeed-clock.h>
>> +    pwm_tach: pwm-tach-controller at 1e610000 {
>> +      compatible = "aspeed,ast2600-pwm-tach";
>> +      reg = <0x1e610000 0x100>;
>> +      clocks = <&syscon ASPEED_CLK_AHB>;
>> +      resets = <&syscon ASPEED_RESET_PWM>;
>> +      #pwm-cells = <3>;
>> +
>> +      fan-0 {
>> +        tach-ch = /bits/ 8 <0x0>;

> What about the PWM connection?

I only want to create the fan monitor without fan control.
So, the PWM connection is unnecessary.

Thanks

>> +      };
>> +
>> +      fan-1 {
>> +        tach-ch = /bits/ 8 <0x1 0x2>;
>> +      };
>> +    };
>> --
>> 2.25.1
>>



More information about the linux-arm-kernel mailing list