dt-bindings: regulator: Document MediaTek MT6316 PMIC Regulators

Add bindings for the regulators found in the MediaTek MT6316 PMIC,
usually found in board designs using the MT6991 Dimensity 9400 and
on MT8196 Kompanio SoC for Chromebooks.

This chip is fully controlled by SPMI and has multiple variants
providing different phase configurations.

Reviewed-by: Chen-Yu Tsai <wenst@chromium.org>
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://patch.msgid.link/20251027110527.21002-2-angelogioacchino.delregno@collabora.com
Signed-off-by: Mark Brown <broonie@kernel.org>

3 files changed, 227 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/regulator/mediatek,mt6316b-regulator.yaml b/Documentation/devicetree/bindings/regulator/mediatek,mt6316b-regulator.yaml
new file mode 100644
index 000000000000..ea595935f4c4
--- /dev/null
+++ b/Documentation/devicetree/bindings/regulator/mediatek,mt6316b-regulator.yaml
@@ -0,0 +1,76 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/regulator/mediatek,mt6316b-regulator.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: MediaTek MT6316 BP/VP SPMI PMIC Regulators
+
+maintainers:
+  - AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
+
+description:
+  The MediaTek MT6316BP/VP PMICs are fully controlled by SPMI interface, both
+  feature four step-down DC/DC (buck) converters, and provides 2+2 Phases,
+  joining Buck 1+2 for the first phase, and Buck 3+4 for the second phase.
+
+properties:
+  compatible:
+    const: mediatek,mt6316b-regulator
+
+  reg:
+    maxItems: 1
+
+patternProperties:
+  "^vbuck(12|34)$":
+    type: object
+    $ref: regulator.yaml#
+    unevaluatedProperties: false
+    properties:
+      regulator-allowed-modes:
+        description: |
+          Allowed Buck regulator operating modes allowed. Valid values below.
+            0 - Normal mode with automatic power saving, reducing the switching
+                frequency when light load conditions are detected
+            1 - Forced Continuous Conduction mode (FCCM) for improved voltage
+                regulation accuracy with constant switching frequency but lower
+                regulator efficiency
+            2 - Forced Low Power mode for improved regulator efficiency, used
+                when no heavy load is expected, will shut down unnecessary IP
+                blocks and secondary phases to reduce quiescent current.
+                This mode does not limit the maximum output current but unless
+                only a light load is applied, there will be regulation accuracy
+                and efficiency losses.
+        minItems: 1
+        maxItems: 3
+        items:
+          enum: [ 0, 1, 2 ]
+
+required:
+  - compatible
+  - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/spmi/spmi.h>
+
+    spmi {
+      #address-cells = <2>;
+      #size-cells = <0>;
+
+      pmic@8 {
+        compatible = "mediatek,mt6316b-regulator";
+        reg = <0x8 SPMI_USID>;
+
+        vbuck12 {
+          regulator-name = "dvdd_core";
+          regulator-min-microvolt = <450000>;
+          regulator-max-microvolt = <965000>;
+          regulator-allowed-modes = <0 1 2>;
+          regulator-enable-ramp-delay = <256>;
+        };
+      };
+    };
+...
diff --git a/Documentation/devicetree/bindings/regulator/mediatek,mt6316c-regulator.yaml b/Documentation/devicetree/bindings/regulator/mediatek,mt6316c-regulator.yaml
new file mode 100644
index 000000000000..186dcd3f11ed
--- /dev/null
+++ b/Documentation/devicetree/bindings/regulator/mediatek,mt6316c-regulator.yaml
@@ -0,0 +1,76 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/regulator/mediatek,mt6316c-regulator.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: MediaTek MT6316 CP/HP/KP SPMI PMIC Regulators
+
+maintainers:
+  - AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
+
+description:
+  The MediaTek MT6316CP/HP/KP PMICs are fully controlled by SPMI interface,
+  features four step-down DC/DC (buck) converters, and provides 3+1 Phases,
+  joining Buck 1+2+4 for the first phase, and uses Buck 3 for the second.
+
+properties:
+  compatible:
+    const: mediatek,mt6316c-regulator
+
+  reg:
+    maxItems: 1
+
+patternProperties:
+  "^vbuck(124|3)$":
+    type: object
+    $ref: regulator.yaml#
+    unevaluatedProperties: false
+    properties:
+      regulator-allowed-modes:
+        description: |
+          Allowed Buck regulator operating modes allowed. Valid values below.
+            0 - Normal mode with automatic power saving, reducing the switching
+                frequency when light load conditions are detected
+            1 - Forced Continuous Conduction mode (FCCM) for improved voltage
+                regulation accuracy with constant switching frequency but lower
+                regulator efficiency
+            2 - Forced Low Power mode for improved regulator efficiency, used
+                when no heavy load is expected, will shut down unnecessary IP
+                blocks and secondary phases to reduce quiescent current.
+                This mode does not limit the maximum output current but unless
+                only a light load is applied, there will be regulation accuracy
+                and efficiency losses.
+        minItems: 1
+        maxItems: 3
+        items:
+          enum: [ 0, 1, 2 ]
+
+required:
+  - compatible
+  - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/spmi/spmi.h>
+
+    spmi {
+      #address-cells = <2>;
+      #size-cells = <0>;
+
+      pmic@6 {
+        compatible = "mediatek,mt6316c-regulator";
+        reg = <0x6 SPMI_USID>;
+
+        vbuck124 {
+          regulator-name = "dvdd_proc_m";
+          regulator-min-microvolt = <450000>;
+          regulator-max-microvolt = <1277500>;
+          regulator-allowed-modes = <0 1 2>;
+          regulator-enable-ramp-delay = <256>;
+        };
+      };
+    };
+...
diff --git a/Documentation/devicetree/bindings/regulator/mediatek,mt6316d-regulator.yaml b/Documentation/devicetree/bindings/regulator/mediatek,mt6316d-regulator.yaml
new file mode 100644
index 000000000000..aa9e9ef3b52d
--- /dev/null
+++ b/Documentation/devicetree/bindings/regulator/mediatek,mt6316d-regulator.yaml
@@ -0,0 +1,75 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/regulator/mediatek,mt6316d-regulator.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: MediaTek MT6316 DP/TP SPMI PMIC Regulators
+
+maintainers:
+  - AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
+
+description:
+  The MediaTek MT6316DP/TP PMICs are fully controlled by SPMI interface, both
+  feature four step-down DC/DC (buck) converters, and provides a single Phase,
+  joining Buck 1+2+3+4.
+
+properties:
+  compatible:
+    const: mediatek,mt6316d-regulator
+
+  reg:
+    maxItems: 1
+
+  vbuck1234:
+    type: object
+    $ref: regulator.yaml#
+    unevaluatedProperties: false
+    properties:
+      regulator-allowed-modes:
+        description: |
+          Allowed Buck regulator operating modes allowed. Valid values below.
+            0 - Normal mode with automatic power saving, reducing the switching
+                frequency when light load conditions are detected
+            1 - Forced Continuous Conduction mode (FCCM) for improved voltage
+                regulation accuracy with constant switching frequency but lower
+                regulator efficiency
+            2 - Forced Low Power mode for improved regulator efficiency, used
+                when no heavy load is expected, will shut down unnecessary IP
+                blocks and secondary phases to reduce quiescent current.
+                This mode does not limit the maximum output current but unless
+                only a light load is applied, there will be regulation accuracy
+                and efficiency losses.
+        minItems: 1
+        maxItems: 3
+        items:
+          enum: [ 0, 1, 2 ]
+
+required:
+  - compatible
+  - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/spmi/spmi.h>
+
+    spmi {
+      #address-cells = <2>;
+      #size-cells = <0>;
+
+      pmic@7 {
+        compatible = "mediatek,mt6316d-regulator";
+        reg = <0x7 SPMI_USID>;
+
+        vbuck1234 {
+          regulator-name = "dvdd_gpustack";
+          regulator-min-microvolt = <400000>;
+          regulator-max-microvolt = <1277500>;
+          regulator-allowed-modes = <0 1 2>;
+          regulator-enable-ramp-delay = <256>;
+        };
+      };
+    };
+...