[PATCH v2 1/4] dt-bindings: hwmon: Add Aspeed AST2600 PWM/Fan

Troy Lee
2021-01-13T07:12:04Z

We add binding for supporting a new AST2600 PWM/Fan hwmon driver.

Changes since v1:
- dt binding with DT schema format

Signed-off-by: Troy Lee <troy_lee@aspeedtech.com>
---
.../hwmon/aspeed,ast2600-pwm-tachometer.yaml | 137 ++++++++++++++++++
1 file changed, 137 insertions(+)
create mode 100644 Documentation/devicetree/bindings/hwmon/aspeed,ast2600-pwm-tachometer.yaml

diff --git a/Documentation/devicetree/bindings/hwmon/aspeed,ast2600-pwm-tachometer.yaml b/Documentation/devicetree/bindings/hwmon/aspeed,ast2600-pwm-tachometer.yaml
new file mode 100644
index 000000000000..b84076a4a338
--- /dev/null
+++ b/Documentation/devicetree/bindings/hwmon/aspeed,ast2600-pwm-tachometer.yaml
@@ -0,0 +1,137 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+
+$id: http://devicetree.org/schemas/hwmon/aspeed,ast2600-pwm-tachometer.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: ASPEED AST2600 PWM and Fan Tacho controller device driver
+
+maintainers:
+ - Ryan Chen <ryan_chen@aspeedtech.com>
+
+description: |
+ The ASPEED PWM controller can support upto 16 PWM outputs. The ASPEED Fan Tacho
+ controller can support upto 16 Fan tachometer inputs.
+ There can be upto 16 fans supported. Each fan can have one PWM output and
+ one Fan tach inputs.
+
+properties:
+ compatible:
+ const: aspeed,ast2600-pwm-tachometer
+
+ "#address-cells":
+ const: 1
+
+ "#size-cells":
+ const: 0
+
+ "#cooling-cells":
+ const: 2
+
+ reg:
+ description:
+ Address and length of the register set for the device.
+
+ clocks:
+ description:
+ phandle to clock provider with the clock number in the second cell
+
+ resets:
+ description:
+ phandle to reset controller with the reset number in the second cell
+
+patternProperties:
+ "@[0-9]+$":
+ type: object
+ description:
+ Under fan subnode there can upto 16 child nodes, with each child node
+ representing a fan. There are 16 fans each fan can have one PWM port and one
+ Fan tach inputs.
+ For PWM port can be configured cooling-levels to create cooling device.
+ Cooling device could be bound to a thermal zone for the thermal control.
+
+ properties:
+ reg:
+ minimum: 0
+ maximum: 15
+ description:
+ This property identify the PWM control channel of this fan.
+
+ fan-tach-ch:
+ $ref: /schemas/types.yaml#/definitions/uint8
+ minimum: 0
+ maximum: 15
+ description:
+ This property identify the fan tach input channel.
+
+ pulses-per-revolution:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ default: 2
+ minimum: 1
+ description:
+ Specify tacho pulse per revolution of the fan.
+
+ cooling-levels:
+ description:
+ PWM duty cycle values in a range from 0 to 255
+ which correspond to thermal cooling states.
+
+ aspeed,pwm-freq:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ default: 25000
+ minimum: 24
+ maximum: 780000
+ description:
+ Specify the frequency of PWM.
+
+ aspeed,inverse-pin:
+ type: boolean
+ description:
+ Inverse PWM output signal.
+
+ aspeed,falling-point:
+ $ref: /schemas/types.yaml#/definitions/uint8
+ default: 10
+ minimum: 0
+ maximum: 255
+ description:
+ Initialize the pulse width.
+
+ required:
+ - fan-tach-ch
+ - reg
+
+ additionalProperties: true
+
+required:
+ - compatible
+ - reg
+
+additionalProperties: false
+
+examples:
+ - |
+ pwm_tacho: pwm-tacho-controller@1e610000 {
+ compatible = "aspeed,ast2600-pwm-tachometer";
+ #address-cells = <1>;
+ #size-cells = <0>;
+ reg = <0x1e610000 0x100>;
+
+ fan@1 {
+ reg = <0x00>;
+ aspeed,pwm-freq = <25000>;
+ cooling-levels = /bits/ 8 <125 151 177 203 229 255>;
+ fan-tach-ch = /bits/ 8 <0x00>;
+ pulses-per-revolution = <2>;
+ };
+
+ fan@2 {
+ reg = <0x01>;
+ aspeed,pwm-freq = <25000>;
+ cooling-levels = /bits/ 8 <125 151 177 203 229 255>;
+ fan-tach-ch = /bits/ 8 <0x01>;
+ pulses-per-revolution = <2>;
+ };
+ };
+...
--
2.25.1