[PATCH v2] regulator: dt-bindings: willsemi,wl2868c: add the WL2868C camera PMIC

[Qianhui Xu]

The WL2868C is a camera power management IC with seven programmable LDOs.
LDO1 and LDO2 share the VIN12 input, LDO3 and LDO4 share VIN34, and LDO5 to
LDO7 have one input each. LDO1 and LDO2 cover 0.496 V to 1.512 V, the other
five cover 1.504 V to 3.544 V, all in 8 mV steps.

It is used on the Lenovo Legion Tab (TB322FC, SM8750), where the two camera
sensors take their DVDD, AVDD and DOVDD rails from LDO1 to LDO5 and LDO7.
Without this binding those supply references cannot be described, so the
camera stack on that board cannot be brought up.

Signed-off-by: Qianhui Xu <xiaqinghuan@xxxxxxxxxxxxxxxx>
---
Changes in v2:
 - Regenerated with git format-patch from a real commit on pristine
   7.3-rc7.  v1 was sent with a diffstat typed into the commit message, so
   the mail carried two of them; that is what Krzysztof called a broken
   patch.
 - Subject rewritten to the regulator tree style:
   "regulator: dt-bindings: willsemi,wl2868c: ..." (was
   "dt-bindings: regulator: ...").
 - MAINTAINERS: the entry was in the V section while its name starts with
   W.  Moved between WIIMOTE and WILOCITY, and renamed from "WILLSEMI
   WL2868C CAMERA PMIC DRIVER" to "WILLSEMI WL2868C CAMERA PMIC" since
   there is no driver in this patch.
 - MAINTAINERS: dropped L: linux-media@xxxxxxxxxxxxxxx, using
   L: linux-kernel@xxxxxxxxxxxxxxx like the other single-file regulator
   bindings.  The device registers as a regulator, so the regulator tree
   is where it belongs.
 - Commit message now says who uses the binding: the camera PMIC on the
   Lenovo Legion Tab (TB322FC, SM8750), supplying DVDD/AVDD/DOVDD of both
   camera sensors.
 - Binding: gave the five input supplies descriptions, grouped the
   regulators patternProperties, used the real board voltage in the
   example, and added the closing "..." marker.
 .../bindings/regulator/willsemi,wl2868c.yaml  | 79 +++++++++++++++++++
 MAINTAINERS                                   |  6 ++
 2 files changed, 85 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/regulator/willsemi,wl2868c.yaml

diff --git a/Documentation/devicetree/bindings/regulator/willsemi,wl2868c.yaml b/Documentation/devicetree/bindings/regulator/willsemi,wl2868c.yaml
new file mode 100644
index 000000000..7abbd53fd
--- /dev/null
+++ b/Documentation/devicetree/bindings/regulator/willsemi,wl2868c.yaml
@@ -0,0 +1,79 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/regulator/willsemi,wl2868c.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Will Semiconductor WL2868C camera power management IC
+
+maintainers:
+  - Qianhui Xu <xiaqinghuan@xxxxxxxxxxxxxxxx>
+
+description:
+  The WL2868C is a camera power management IC with seven programmable LDOs.
+  LDO1 and LDO2 share the VIN12 input and cover 0.496 V to 1.512 V; LDO3 and
+  LDO4 share VIN34, and LDO5 to LDO7 have one input each, covering 1.504 V to
+  3.544 V. All outputs are programmable in 8 mV steps.
+
+properties:
+  compatible:
+    const: willsemi,wl2868c
+
+  reg:
+    maxItems: 1
+
+  reset-gpios:
+    maxItems: 1
+    description: Active-low RST_N input.
+
+  vin12-supply:
+    description: Input supply for LDO1 and LDO2.
+
+  vin34-supply:
+    description: Input supply for LDO3 and LDO4.
+
+  vin5-supply:
+    description: Input supply for LDO5.
+
+  vin6-supply:
+    description: Input supply for LDO6.
+
+  vin7-supply:
+    description: Input supply for LDO7.
+
+  regulators:
+    type: object
+    additionalProperties: false
+
+    patternProperties:
+      "^ldo[1-7]$":
+        type: object
+        $ref: regulator.yaml#
+        unevaluatedProperties: false
+
+required:
+  - compatible
+  - reg
+  - regulators
+
+additionalProperties: false
+
+examples:
+  - |
+    i2c {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        pmic@2f {
+            compatible = "willsemi,wl2868c";
+            reg = <0x2f>;
+
+            regulators {
+                ldo1 {
+                    regulator-min-microvolt = <1128000>;
+                    regulator-max-microvolt = <1128000>;
+                };
+            };
+        };
+    };
+...
diff --git a/MAINTAINERS b/MAINTAINERS
index f53047aa8..632b17b3e 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -29413,6 +29413,12 @@ L:	linux-input@xxxxxxxxxxxxxxx
 S:	Maintained
 F:	drivers/hid/hid-wiimote*
 
+WILLSEMI WL2868C CAMERA PMIC
+M:	Qianhui Xu <xiaqinghuan@xxxxxxxxxxxxxxxx>
+L:	linux-kernel@xxxxxxxxxxxxxxx
+S:	Maintained
+F:	Documentation/devicetree/bindings/regulator/willsemi,wl2868c.yaml
+
 WILOCITY WIL6210 WIRELESS DRIVER
 L:	linux-wireless@xxxxxxxxxxxxxxx
 S:	Orphan
-- 
2.53.0