dt-bindings: hwmon: Convert ltc2978.txt to yaml

Convert binding doc ltc2978.txt to yaml format.
Additional change:
- add i2c node.

Fix below warning:
arch/arm64/boot/dts/freescale/fsl-lx2160a-clearfog-cx.dtb: /soc/i2c@2000000/i2c-mux@77/i2c@2/regulator@5c:
	failed to match any schema with compatible: ['lltc,ltc3882']

Signed-off-by: Frank Li <[email protected]>
Reviewed-by: Rob Herring (Arm) <[email protected]>
Message-ID: <[email protected]>
Signed-off-by: Guenter Roeck <[email protected]>

Author: nxpfrankli

Documentation/devicetree/bindings/hwmon/lltc,ltc2978.yaml

@@ -0,0 +1,94 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/hwmon/lltc,ltc2978.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Octal Digital Power-supply monitor/supervisor/sequencer/margin controller.
+
+maintainers:
+  - Frank Li <[email protected]>
+
+properties:
+  compatible:
+    enum:
+      - lltc,ltc2972
+      - lltc,ltc2974
+      - lltc,ltc2975
+      - lltc,ltc2977
+      - lltc,ltc2978
+      - lltc,ltc2979
+      - lltc,ltc2980
+      - lltc,ltc3880
+      - lltc,ltc3882
+      - lltc,ltc3883
+      - lltc,ltc3884
+      - lltc,ltc3886
+      - lltc,ltc3887
+      - lltc,ltc3889
+      - lltc,ltc7880
+      - lltc,ltm2987
+      - lltc,ltm4664
+      - lltc,ltm4675
+      - lltc,ltm4676
+      - lltc,ltm4677
+      - lltc,ltm4678
+      - lltc,ltm4680
+      - lltc,ltm4686
+      - lltc,ltm4700
+
+  reg:
+    maxItems: 1
+
+  regulators:
+    type: object
+    description: |
+      list of regulators provided by this controller.
+      Valid names of regulators depend on number of supplies supported per device:
+      * ltc2972 vout0 - vout1
+      * ltc2974, ltc2975 : vout0 - vout3
+      * ltc2977, ltc2979, ltc2980, ltm2987 : vout0 - vout7
+      * ltc2978 : vout0 - vout7
+      * ltc3880, ltc3882, ltc3884, ltc3886, ltc3887, ltc3889 : vout0 - vout1
+      * ltc7880 : vout0 - vout1
+      * ltc3883 : vout0
+      * ltm4664 : vout0 - vout1
+      * ltm4675, ltm4676, ltm4677, ltm4678 : vout0 - vout1
+      * ltm4680, ltm4686 : vout0 - vout1
+      * ltm4700 : vout0 - vout1
+
+    patternProperties:
+      "^vout[0-7]$":
+        $ref: /schemas/regulator/regulator.yaml#
+        type: object
+        unevaluatedProperties: false
+
+    additionalProperties: false
+
+required:
+  - compatible
+  - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    i2c {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        regulator@5e {
+            compatible = "lltc,ltc2978";
+            reg = <0x5e>;
+
+            regulators {
+                vout0 {
+                     regulator-name = "FPGA-2.5V";
+                };
+                vout2 {
+                     regulator-name = "FPGA-1.5V";
+                };
+            };
+        };
+    };
+