dt-bindings: iio: io-channel-mux: allow duplicate channel, labels

This is needed since an empty channel label is used to indicate an
unused channel, and there can be more that one of those.

Fixes the following problem reported by dtbs_check:
envelope-detector-mux: channels: ['', '', 'sync-1', 'in', 'out', 'sync-2', 'sys-reg', 'ana-reg'] has non-unique elements
	arch/arm/boot/dts/at91-tse850-3.dt.yaml

Suggested-by: Rob Herring <robh@kernel.org>
Signed-off-by: Peter Rosin <peda@axentia.se>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/Documentation/devicetree/bindings/iio/multiplexer/io-channel-mux.yaml b/Documentation/devicetree/bindings/iio/multiplexer/io-channel-mux.yaml
index 80b6229a6fad8dbb833fc3420643e9fa70f37a9e..611ad4444cf0cb9c4083e7b2014ee1fae80442d9 100644 (file)
--- a/Documentation/devicetree/bindings/iio/multiplexer/io-channel-mux.yaml
+++ b/Documentation/devicetree/bindings/iio/multiplexer/io-channel-mux.yaml
@@ -35,9 +35,10 @@ properties:
   mux-control-names: true
 
   channels:
-    $ref: /schemas/types.yaml#/definitions/string-array
+    $ref: /schemas/types.yaml#/definitions/non-unique-string-array
     description:
-      List of strings, labeling the mux controller states.
+      List of strings, labeling the mux controller states. An empty
+      string for a state means that the channel is not available.
 
   settle-time-us:
     default: 0