dt-bindings: mmc: Add optional generic properties for mmc

Add optional properties for mmc hosts which are used to set clk delays
for different speed modes in the controller.

Signed-off-by: Manish Narani <manish.narani@xilinx.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Documentation/devicetree/bindings/mmc/mmc-controller.yaml

@@ -333,6 +333,18 @@ patternProperties:
     required:
       - reg
 
+  "^clk-phase-(legacy|sd-hs|mmc-(hs|hs[24]00|ddr52)|uhs-(sdr(12|25|50|104)|ddr50))$":
+    minItems: 2
+    maxItems: 2
+    allOf:
+      - $ref: /schemas/types.yaml#/definitions/uint32
+      - minimum: 0
+        maximum: 359
+    description:
+      Set the clock (phase) delays which are to be configured in the
+      controller while switching to particular speed mode. These values
+      are in pair of degrees.
+
 dependencies:
   cd-debounce-delay-ms: [ cd-gpios ]
   fixed-emmc-driver-type: [ non-removable ]
@@ -351,6 +363,7 @@ examples:
         keep-power-in-suspend;
         wakeup-source;
         mmc-pwrseq = <&sdhci0_pwrseq>;
+        clk-phase-sd-hs = <63>, <72>;
     };
 
   - |