[PATCH v5 1/4] dt-bindings: rtc: Document NVIDIA VRS RTC

[Shubhi Garg <shgarg@nvidia.com>]

Add device tree bindings for NVIDIA VRS (Voltage Regulator Specification)
RTC device. NVIDIA VRS RTC provides functionality to get/set system time,
retain system time across boot, wake system from suspend and shutdown
state.

Supported platforms:
- NVIDIA Jetson AGX Orin Developer Kit
- NVIDIA IGX Orin Development Kit
- NVIDIA Jetson Orin NX Developer Kit
- NVIDIA Jetson Orin Nano Developer Kit

Signed-off-by: Shubhi Garg <shgarg@nvidia.com>
---

v5:
- moved device tree bindings from mfd to rtc
- changed dtb node name to rtc@3c
- changed compatible string to "nvidia,vrs10-rtc" 

v4:
- no changes

v3:
- fixed device tree node name to generic "pmic@3c"
- fixed indentation

v2:
- fixed copyrights
- updated description with RTC information
- added status node in dtb node example

 .../bindings/rtc/nvidia,vrs10-rtc.yaml        | 57 +++++++++++++++++++
 1 file changed, 57 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/rtc/nvidia,vrs10-rtc.yaml

diff --git a/Documentation/devicetree/bindings/rtc/nvidia,vrs10-rtc.yaml b/Documentation/devicetree/bindings/rtc/nvidia,vrs10-rtc.yaml
new file mode 100644
index 000000000000..b7eea5f03e5a
--- /dev/null
+++ b/Documentation/devicetree/bindings/rtc/nvidia,vrs10-rtc.yaml
@@ -0,0 +1,57 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/rtc/nvidia,vrs10-rtc.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: NVIDIA Voltage Regulator Specification Real Time Clock
+
+maintainers:
+  - Shubhi Garg <shgarg@nvidia.com>
+
+description:
+  NVIDIA VRS (Voltage Regulator Specification) RTC provides 32kHz RTC clock
+  support with backup battery for system timing. It provides alarm functionality
+  to wake system from suspend and shutdown state. The device also acts as an
+  interrupt controller for managing interrupts from the VRS.
+
+properties:
+  compatible:
+    const: nvidia,vrs10-rtc
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  interrupt-controller: true
+
+  '#interrupt-cells':
+    const: 2
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - interrupt-controller
+  - '#interrupt-cells'
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/irq.h>
+    i2c {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        rtc@3c {
+            compatible = "nvidia,vrs10-rtc";
+            reg = <0x3c>;
+            interrupt-parent = <&pmc>;
+            interrupts = <24 IRQ_TYPE_LEVEL_LOW>;
+            interrupt-controller;
+            #interrupt-cells = <2>;
+        };
+    };
-- 
2.43.0