[PATCH v3 1/3] dt-bindings: hwmon: Add adt7475 fan/pwm properties

[Chris Packham <chris.packham@alliedtelesis.co.nz>]

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@alliedtelesis.co.nz>
---

Notes:
    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    | 25 ++++++++++++++++++-
 1 file changed, 24 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/hwmon/adt7475.yaml b/Documentation/devicetree/bindings/hwmon/adt7475.yaml
index 051c976ab711..99bd689ae0cd 100644
--- a/Documentation/devicetree/bindings/hwmon/adt7475.yaml
+++ b/Documentation/devicetree/bindings/hwmon/adt7475.yaml
@@ -51,6 +51,15 @@ 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 frequency in hertz - 0, 11, 14, 22, 29, 35, 44, 58, 88, 22500
+      - 2: PWM flags 0 or PWM_POLARITY_INVERTED
+      - 3: The default pwm duty cycle - 0-255
+
 patternProperties:
   "^adi,bypass-attenuator-in[0-4]$":
     description: |
@@ -81,6 +90,10 @@ patternProperties:
       - smbalert#
       - gpio
 
+  "^fan-[0-9]+$":
+    $ref: fan-common.yaml#
+    unevaluatedProperties: false
+
 required:
   - compatible
   - reg
@@ -89,11 +102,12 @@ 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 +115,14 @@ examples:
         adi,pwm-active-state = <1 0 1>;
         adi,pin10-function = "smbalert#";
         adi,pin14-function = "tach4";
+        #pwm-cells = <4>;
+
+        fan-0 {
+          pwms = <&pwm 0 22500 PWM_POLARITY_INVERTED 255>;
+        };
+
+        fan-1 {
+          pwms = <&pwm 2 22500 PWM_POLARITY_INVERTED 255>;
+        };
       };
     };
-- 
2.45.1