[PATCH v2 3/4] regulator: dt-bindings: Add Allwinner D1 LDOs

[Samuel Holland <samuel@sholland.org>]

The Allwinner D1 SoC contains two pairs of in-package LDOs. One pair is
for general purpose use. LDOA generally powers the board's 1.8 V rail.
LDOB generally powers the in-package DRAM, where applicable.

The other pair of LDOs powers the analog power domains inside the SoC,
including the audio codec, thermal sensor, and ADCs. These LDOs require
a 0.9 V bandgap voltage reference. The calibration value for the voltage
reference is stored in an eFuse, accessed via an NVMEM cell.

Neither LDO control register is in its own MMIO range; instead, each
regulator device relies on a regmap/syscon exported by its parent.

Signed-off-by: Samuel Holland <samuel@sholland.org>
---

Changes in v2:
 - Remove syscon property from bindings
 - Update binding examples to fix warnings and provide context

 .../allwinner,sun20i-d1-analog-ldos.yaml      | 65 +++++++++++++++++++
 .../allwinner,sun20i-d1-system-ldos.yaml      | 57 ++++++++++++++++
 2 files changed, 122 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/regulator/allwinner,sun20i-d1-analog-ldos.yaml
 create mode 100644 Documentation/devicetree/bindings/regulator/allwinner,sun20i-d1-system-ldos.yaml

diff --git a/Documentation/devicetree/bindings/regulator/allwinner,sun20i-d1-analog-ldos.yaml b/Documentation/devicetree/bindings/regulator/allwinner,sun20i-d1-analog-ldos.yaml
new file mode 100644
index 000000000000..19c984ef4e53
--- /dev/null
+++ b/Documentation/devicetree/bindings/regulator/allwinner,sun20i-d1-analog-ldos.yaml
@@ -0,0 +1,65 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/regulator/allwinner,sun20i-d1-analog-ldos.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Allwinner D1 Analog LDOs
+
+description:
+  Allwinner D1 contains a set of LDOs which are designed to supply analog power
+  inside and outside the SoC. They are controlled by a register within the audio
+  codec MMIO space, but which is not part of the audio codec clock/reset domain.
+
+maintainers:
+  - Samuel Holland <samuel@sholland.org>
+
+properties:
+  compatible:
+    enum:
+      - allwinner,sun20i-d1-analog-ldos
+
+  nvmem-cells:
+    items:
+      - description: NVMEM cell for the calibrated bandgap reference trim value
+
+  nvmem-cell-names:
+    items:
+      - const: bg_trim
+
+patternProperties:
+  "^(aldo|hpldo)$":
+    type: object
+    $ref: regulator.yaml#
+
+required:
+  - compatible
+  - nvmem-cells
+  - nvmem-cell-names
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    audio-codec@2030000 {
+        compatible = "simple-mfd", "syscon";
+        reg = <0x2030000 0x1000>;
+
+        regulators {
+            compatible = "allwinner,sun20i-d1-analog-ldos";
+            nvmem-cells = <&bg_trim>;
+            nvmem-cell-names = "bg_trim";
+
+            reg_aldo: aldo {
+                regulator-min-microvolt = <1800000>;
+                regulator-max-microvolt = <1800000>;
+            };
+
+            reg_hpldo: hpldo {
+                regulator-min-microvolt = <1800000>;
+                regulator-max-microvolt = <1800000>;
+            };
+        };
+    };
+
+...
diff --git a/Documentation/devicetree/bindings/regulator/allwinner,sun20i-d1-system-ldos.yaml b/Documentation/devicetree/bindings/regulator/allwinner,sun20i-d1-system-ldos.yaml
new file mode 100644
index 000000000000..c95030a827d6
--- /dev/null
+++ b/Documentation/devicetree/bindings/regulator/allwinner,sun20i-d1-system-ldos.yaml
@@ -0,0 +1,57 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/regulator/allwinner,sun20i-d1-system-ldos.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Allwinner D1 System LDOs
+
+description:
+  Allwinner D1 contains a pair of general-purpose LDOs which are designed to
+  supply power inside and outside the SoC. They are controlled by a register
+  within the system control MMIO space.
+
+maintainers:
+  - Samuel Holland <samuel@sholland.org>
+
+properties:
+  compatible:
+    enum:
+      - allwinner,sun20i-d1-system-ldos
+
+patternProperties:
+  "^(ldoa|ldob)$":
+    type: object
+    $ref: regulator.yaml#
+
+required:
+  - compatible
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    syscon@3000000 {
+        compatible = "allwinner,sun20i-d1-system-control";
+        reg = <0x3000000 0x1000>;
+        ranges;
+        #address-cells = <1>;
+        #size-cells = <1>;
+
+        regulators {
+            compatible = "allwinner,sun20i-d1-system-ldos";
+
+            reg_ldoa: ldoa {
+                regulator-min-microvolt = <1800000>;
+                regulator-max-microvolt = <1800000>;
+            };
+
+            reg_ldob: ldob {
+                regulator-name = "vcc-dram";
+                regulator-min-microvolt = <1500000>;
+                regulator-max-microvolt = <1500000>;
+            };
+        };
+    };
+
+...
-- 
2.35.1