From: Oleksij Rempel <o.rempel@pengutronix.de>
Date: Tue, 10 Feb 2026 13:51:09 +0000 (+0100)
Subject: dt-bindings: iio: dac: maxim,ds4424: add maxim,rfs-ohms property
X-Git-Tag: v7.1-rc1~17^2~120^2~16
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f789b8cc39f0dc46b1654aff84e420927bea4272;p=thirdparty%2Fkernel%2Fstable.git

dt-bindings: iio: dac: maxim,ds4424: add maxim,rfs-ohms property

The Maxim DS4422/DS4424 and DS4402/DS4404 current DACs determine their
full-scale output current via external resistors (Rfs) connected to the
FSx pins. Without knowing these values, the full-scale range of the
hardware is undefined.

Add the 'maxim,rfs-ohms' property to describe these physical components.
This property is required to provide a complete description of the
hardware configuration.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
---

diff --git a/Documentation/devicetree/bindings/iio/dac/maxim,ds4424.yaml b/Documentation/devicetree/bindings/iio/dac/maxim,ds4424.yaml
index efe63e6cb55d7..4323df2036acb 100644
--- a/Documentation/devicetree/bindings/iio/dac/maxim,ds4424.yaml
+++ b/Documentation/devicetree/bindings/iio/dac/maxim,ds4424.yaml
@@ -27,9 +27,43 @@ properties:
 
   vcc-supply: true
 
+  maxim,rfs-ohms:
+    description: |
+      Array of resistance values in Ohms for the external Rfs resistors
+      connected to the FS pins. These values determine the full-scale
+      output current. The actual resistance depends on the chip variant
+      and specific hardware design requirements.
+    minItems: 2
+    maxItems: 4
+
 required:
   - compatible
   - reg
+  - maxim,rfs-ohms
+
+allOf:
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - maxim,ds4402
+              - maxim,ds4422
+    then:
+      properties:
+        maxim,rfs-ohms:
+          maxItems: 2
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - maxim,ds4404
+              - maxim,ds4424
+    then:
+      properties:
+        maxim,rfs-ohms:
+          minItems: 4
 
 additionalProperties: false
 
@@ -43,6 +77,7 @@ examples:
             compatible = "maxim,ds4424";
             reg = <0x10>; /* When A0, A1 pins are ground */
             vcc-supply = <&vcc_3v3>;
+            maxim,rfs-ohms = <40000>, <40000>, <40000>, <40000>;
         };
     };
 ...