dt-bindings: phy: cadence-torrent: Add binding to specify SSC mode

Add binding to specify Spread Spectrum Clocking mode used.

Signed-off-by: Swapnil Jakhade <sjakhade@cadence.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/1600280911-9214-7-git-send-email-sjakhade@cadence.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
diff --git a/Documentation/devicetree/bindings/phy/phy-cadence-torrent.yaml b/Documentation/devicetree/bindings/phy/phy-cadence-torrent.yaml
index 4071438..a7ee19d 100644
--- a/Documentation/devicetree/bindings/phy/phy-cadence-torrent.yaml
+++ b/Documentation/devicetree/bindings/phy/phy-cadence-torrent.yaml
@@ -87,6 +87,15 @@
         enum: [1, 2, 4]
         default: 4
 
+      cdns,ssc-mode:
+        description:
+          Specifies the Spread Spectrum Clocking mode used. It can be NO_SSC,
+          EXTERNAL_SSC or INTERNAL_SSC.
+          Refer include/dt-bindings/phy/phy-cadence-torrent.h for the constants to be used.
+        $ref: /schemas/types.yaml#/definitions/uint32
+        enum: [0, 1, 2]
+        default: 0
+
       cdns,max-bit-rate:
         description:
           Maximum DisplayPort link bit rate to use, in Mbps