dt-bindings: clk: vc5: Add properties for configuring the SD/OE pin

These properties allow configuring the SD/OE pin as described in the
datasheet.

Signed-off-by: Sean Anderson <sean.anderson@seco.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Luca Ceresoli <luca@lucaceresoli.net>
Link: https://lore.kernel.org/r/20210809223813.3766204-1-sean.anderson@seco.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

Author: sean-anderson-seco

Documentation/devicetree/bindings/clock/idt,versaclock5.yaml

@@ -30,6 +30,20 @@ description: |
     3 -- OUT3
     4 -- OUT4
 
+  The idt,shutdown and idt,output-enable-active properties control the
+  SH (en_global_shutdown) and SP bits of the Primary Source and Shutdown
+  Register, respectively. Their behavior is summarized by the following
+  table:
+
+  SH SP Output when the SD/OE pin is Low/High
+  == == =====================================
+   0  0 Active/Inactive
+   0  1 Inactive/Active
+   1  0 Active/Shutdown
+   1  1 Inactive/Shutdown
+
+  The case where SH and SP are both 1 is likely not very interesting.
+
 maintainers:
   - Luca Ceresoli <luca@lucaceresoli.net>
 
@@ -64,6 +78,26 @@ properties:
     maximum: 22760
     description: Optional load capacitor for XTAL1 and XTAL2
 
+  idt,shutdown:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    enum: [0, 1]
+    description: |
+      If 1, this enables the shutdown functionality: the chip will be
+      shut down if the SD/OE pin is driven high. If 0, this disables the
+      shutdown functionality: the chip will never be shut down based on
+      the value of the SD/OE pin. This property corresponds to the SH
+      bit of the Primary Source and Shutdown Register.
+
+  idt,output-enable-active:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    enum: [0, 1]
+    description: |
+      If 1, this enables output when the SD/OE pin is high, and disables
+      output when the SD/OE pin is low. If 0, this disables output when
+      the SD/OE pin is high, and enables output when the SD/OE pin is
+      low. This corresponds to the SP bit of the Primary Source and
+      Shutdown Register.
+
 patternProperties:
   "^OUT[1-4]$":
     type: object
@@ -90,6 +124,8 @@ required:
   - compatible
   - reg
   - '#clock-cells'
+  - idt,shutdown
+  - idt,output-enable-active
 
 allOf:
   - if:
@@ -139,6 +175,10 @@ examples:
             clocks = <&ref25m>;
             clock-names = "xin";
 
+            /* Set the SD/OE pin's settings */
+            idt,shutdown = <0>;
+            idt,output-enable-active = <0>;
+
             OUT1 {
                 idt,mode = <VC5_CMOSD>;
                 idt,voltage-microvolt = <1800000>;