Add Richtek RT5759 buck converter support

new file mode 100644
index 00000000..0a4c957
@@ -0,0 +1,90 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/regulator/richtek,rt5759-regulator.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Richtek RT5759 High Performance DCDC Converter
+
+maintainers:
+  - ChiYuan Huang <[email protected]>
+
+description: |
+  The RT5759 is a high-performance, synchronous step-down DC-DC converter that
+  can deliver up to 9A output current from 3V to 6.5V input supply, The output
+  voltage can be programmable with I2C controlled 7-Bit VID.
+
+  Datasheet is available at
+  https://www.richtek.com/assets/product_file/RT5759/DS5759-00.pdf
+
+properties:
+  compatible:
+    enum:
+      - richtek,rt5759
+      - richtek,rt5759a
+
+  reg:
+    maxItems: 1
+
+  regulator-allowed-modes:
+    description: |
+      buck allowed operating mode
+        0: auto mode (PSKIP: pulse skipping)
+        1: force pwm mode
+    items:
+      enum: [0, 1]
+
+  richtek,watchdog-enable:
+    description: enable the external watchdog reset pin listening
+    type: boolean
+
+allOf:
+  - $ref: regulator.yaml#
+
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: richtek,rt5759
+    then:
+      properties:
+        richtek,watchdog-enable: false
+
+required:
+  - compatible
+  - reg
+
+unevaluatedProperties: false
+
+examples:
+  # example 1 for RT5759
+  - |
+    i2c {
+      #address-cells = <1>;
+      #size-cells = <0>;
+
+      regulator@62 {
+        compatible = "richtek,rt5759";
+        reg = <0x62>;
+        regulator-name = "rt5759-buck";
+        regulator-min-microvolt = <600000>;
+        regulator-max-microvolt = <1500000>;
+        regulator-boot-on;
+      };
+    };
+  # example 2 for RT5759A
+  - |
+    i2c {
+      #address-cells = <1>;
+      #size-cells = <0>;
+
+      regulator@62 {
+        compatible = "richtek,rt5759a";
+        reg = <0x62>;
+        regulator-name = "rt5759a-buck";
+        regulator-min-microvolt = <600000>;
+        regulator-max-microvolt = <1725000>;
+        regulator-boot-on;
+        richtek,watchdog-enable;
+      };
+    };

index 1c35fed2..72e0318 100644
@@ -1046,6 +1046,16 @@ config REGULATOR_RT5033
 	  RT5033 PMIC. The device supports multiple regulators like
 	  current source, LDO and Buck.
 
+config REGULATOR_RT5759
+	tristate "Richtek RT5759 Regulator"
+	depends on I2C
+	select REGMAP_I2C
+	help
+	  This adds support for voltage regulator in Richtek RT5759.
+	  The RT5759 is a high-performance, synchronous step-down DC-DC
+	  converter that can deliver up to 9A output current from 3V to 6.5V
+	  input supply.
+
 config REGULATOR_RT6160
 	tristate "Richtek RT6160 BuckBoost voltage regulator"
 	depends on I2C

index 2e1b087..239a3a3 100644
@@ -126,6 +126,7 @@ obj-$(CONFIG_REGULATOR_ROHM)	+= rohm-regulator.o
 obj-$(CONFIG_REGULATOR_RT4801)	+= rt4801-regulator.o
 obj-$(CONFIG_REGULATOR_RT4831)	+= rt4831-regulator.o
 obj-$(CONFIG_REGULATOR_RT5033)	+= rt5033-regulator.o
+obj-$(CONFIG_REGULATOR_RT5759)	+= rt5759-regulator.o
 obj-$(CONFIG_REGULATOR_RT6160)	+= rt6160-regulator.o
 obj-$(CONFIG_REGULATOR_RT6245)	+= rt6245-regulator.o
 obj-$(CONFIG_REGULATOR_RTMV20)	+= rtmv20-regulator.o