dt-bindings: Add generic bindings for PECI

Add device tree bindings for the PECI controller.
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Acked-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Iwona Winiarska <iwona.winiarska@intel.com>
Link: https://lore.kernel.org/r/20220208153639.255278-2-iwona.winiarska@intel.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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

+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/peci/peci-controller.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Generic Device Tree Bindings for PECI
+
+maintainers:
+  - Iwona Winiarska <iwona.winiarska@intel.com>
+
+description:
+  PECI (Platform Environment Control Interface) is an interface that provides a
+  communication channel from Intel processors and chipset components to external
+  monitoring or control devices.
+
+properties:
+  $nodename:
+    pattern: "^peci-controller(@.*)?$"
+
+  cmd-timeout-ms:
+    description:
+      Command timeout in units of ms.
+
+additionalProperties: true
+
+examples:
+  - |
+    peci-controller@1e78b000 {
+      reg = <0x1e78b000 0x100>;
+      cmd-timeout-ms = <500>;
+    };
+...