dt-bindings: iio: adc: Add NXP IMX93 ADC

The IMX93 SoC has a new ADC IP, so add binding documentation
for NXP IMX93 ADC.
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Haibo Chen <haibo.chen@nxp.com>
Link: https://lore.kernel.org/r/20230117135137.1735536-3-haibo.chen@nxp.comSigned-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

Documentation/devicetree/bindings/iio/adc/nxp,imx93-adc.yaml

+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iio/adc/nxp,imx93-adc.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: NXP iMX93 ADC
+
+maintainers:
+  - Haibo Chen <haibo.chen@nxp.com>
+
+description:
+  The ADC on iMX93 is a 8-channel 12-bit 1MS/s ADC with 4 channels
+  connected to pins. it support normal and inject mode, include
+  One-Shot and Scan (continuous) conversions. Programmable DMA
+  enables for each channel  Also this ADC contain alternate analog
+  watchdog thresholds, select threshold through input ports. And
+  also has Self-test logic and Software-initiated calibration.
+
+properties:
+  compatible:
+    const: nxp,imx93-adc
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    items:
+      - description: WDGnL, watchdog threshold interrupt requests.
+      - description: WDGnH, watchdog threshold interrupt requests.
+      - description: normal conversion, include EOC (End of Conversion),
+          ECH (End of Chain), JEOC (End of Injected Conversion) and
+          JECH (End of injected Chain).
+      - description: Self-testing Interrupts.
+
+  clocks:
+    maxItems: 1
+
+  clock-names:
+    const: ipg
+
+  vref-supply:
+    description:
+      The reference voltage which used to establish channel scaling.
+
+  "#io-channel-cells":
+    const: 1
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - clocks
+  - clock-names
+  - vref-supply
+  - "#io-channel-cells"
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/irq.h>
+    #include <dt-bindings/clock/imx93-clock.h>
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+    soc {
+        #address-cells = <1>;
+        #size-cells = <1>;
+        adc@44530000 {
+            compatible = "nxp,imx93-adc";
+            reg = <0x44530000 0x10000>;
+            interrupts = <GIC_SPI 217 IRQ_TYPE_LEVEL_HIGH>,
+                         <GIC_SPI 218 IRQ_TYPE_LEVEL_HIGH>,
+                         <GIC_SPI 219 IRQ_TYPE_LEVEL_HIGH>,
+                         <GIC_SPI 268 IRQ_TYPE_LEVEL_HIGH>;
+            clocks = <&clk IMX93_CLK_ADC1_GATE>;
+            clock-names = "ipg";
+            vref-supply = <&reg_vref_1v8>;
+            #io-channel-cells = <1>;
+        };
+    };
+...