Add fan child nodes that allow describing the connections for the
ADT7475 to the fans it controls. This also allows setting some
initial values for the pwm duty cycle and frequency.
Signed-off-by: Chris Packham <chris.packham@xxxxxxxxxxxxxxxxxxx>
---
Notes:
Changes in v5:
- Use nanoseconds for PWM frequency and duty cycle as per existing
conventions for PWMs
- Set flags to 0 in example to match adi,pwm-active-state setting
Changes in v4:
- 0 is not a valid frequency value
Changes in v3:
- Use the pwm provider/consumer bindings
Changes in v2:
- Document 0 as a valid value (leaves hardware as-is)
.../devicetree/bindings/hwmon/adt7475.yaml | 35 ++++++++++++++++++-
1 file changed, 34 insertions(+), 1 deletion(-)
diff --git a/Documentation/devicetree/bindings/hwmon/adt7475.yaml b/Documentation/devicetree/bindings/hwmon/adt7475.yaml
index 051c976ab711..df2b5b889e4d 100644
--- a/Documentation/devicetree/bindings/hwmon/adt7475.yaml
+++ b/Documentation/devicetree/bindings/hwmon/adt7475.yaml
@@ -51,6 +51,24 @@ properties:
enum: [0, 1]
default: 1
+ "#pwm-cells":
+ const: 4
+ description: |
+ Number of cells in a PWM specifier.
+ - 0: The PWM channel
+ - 1: The PWM period in nanoseconds
+ - 90909091 (11 Hz)
+ - 71428571 (14 Hz)
+ - 45454545 (22 Hz)
+ - 34482759 (29 Hz)
+ - 28571429 (35 Hz)
+ - 22727273 (44 Hz)
+ - 17241379 (58 Hz)
+ - 11363636 (88 Hz)
+ - 44444 (22 kHz)
+ - 2: PWM flags 0 or PWM_POLARITY_INVERTED
+ - 3: The default PWM duty cycle in nanoseconds
+
patternProperties:
"^adi,bypass-attenuator-in[0-4]$":
description: |
@@ -81,6 +99,10 @@ patternProperties:
- smbalert#
- gpio
+ "^fan-[0-9]+$":
+ $ref: fan-common.yaml#
+ unevaluatedProperties: false
+
required:
- compatible
- reg
@@ -89,11 +111,12 @@ additionalProperties: false
examples:
- |
+ #include <dt-bindings/pwm/pwm.h>
i2c {
#address-cells = <1>;
#size-cells = <0>;
- hwmon@2e {
+ pwm: hwmon@2e {
compatible = "adi,adt7476";
reg = <0x2e>;
adi,bypass-attenuator-in0 = <1>;
@@ -101,5 +124,15 @@ examples:
adi,pwm-active-state = <1 0 1>;
adi,pin10-function = "smbalert#";
adi,pin14-function = "tach4";
+ #pwm-cells = <4>;
+
+ /* PWMs at 22.5 kHz frequency, 50% duty*/
+ fan-0 {
+ pwms = <&pwm 0 44444 0 22222>;
+ };
+
+ fan-1 {
+ pwms = <&pwm 2 44444 0 22222>;
+ };
};
};
--
2.45.2
