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

From: Samuel Holland
Date: Tue Aug 02 2022 - 01:32:36 EST


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@xxxxxxxxxxxx>
---

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@xxxxxxxxxxxx>
+
+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#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Allwinner D1 System LDOs
+
+description:
+ Allwinner D1 contains a pair of general-purpose LDOs which are designed to
+ supply power inside and outside the SoC. They are controlled by a register
+ within the system control MMIO space.
+
+maintainers:
+ - Samuel Holland <samuel@xxxxxxxxxxxx>
+
+properties:
+ compatible:
+ enum:
+ - allwinner,sun20i-d1-system-ldos
+
+patternProperties:
+ "^(ldoa|ldob)$":
+ 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