[PATCH 1/6] dt-bindings: clocks: add binding for generic clock-generators

Heiko Stuebner
2024-07-09T12:31:47Z

In contrast to fixed clocks that are described as ungateable, boards
sometimes use additional clock generators for things like PCIe reference
clocks, that need actual supplies to get enabled and enable-gpios to be
toggled for them to work.

This adds a binding for such clock generators that are not configurable
themself, but need to handle supplies for them to work.

While in a lot of cases the type of the IC used is described in board
schematics, in some cases just a generic type description like
"100MHz, 3.3V" might also be used. The binding therefore allows both
cases. Specifying the type is of course preferred.

The clock-frequency is set in devicetree, because while some clock
generators have pins to decide between multipls output rates, those
are generally set statically on the board-layout-level.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
---
.../bindings/clock/clock-generator.yaml | 62 +++++++++++++++++++
1 file changed, 62 insertions(+)
create mode 100644 Documentation/devicetree/bindings/clock/clock-generator.yaml

diff --git a/Documentation/devicetree/bindings/clock/clock-generator.yaml b/Documentation/devicetree/bindings/clock/clock-generator.yaml
new file mode 100644
index 0000000000000..f44e61e414e89
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/clock-generator.yaml
@@ -0,0 +1,62 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/clock/clock-generator.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Simple clock generators
+
+maintainers:
+ - Heiko Stuebner <heiko@sntech.de>
+
+properties:
+ $nodename:
+ anyOf:
+ - description:
+ Preferred name is 'clock-<freq>' with <freq> being the output
+ frequency as defined in the 'clock-frequency' property.
+ pattern: "^clock-([0-9]+|[a-z0-9-]+)$"
+ - description: Any name allowed
+ deprecated: true
+
+ compatible:
+ oneOf:
+ - const: clock-generator
+ - items:
+ - enum:
+ - diodes,pi6c557-03b
+ - diodes,pi6c557-05b
+ - const: clock-generator
+
+ "#clock-cells":
+ const: 0
+
+ clock-frequency: true
+
+ clock-output-names:
+ maxItems: 1
+
+ enable-gpios:
+ description:
+ Contains a single GPIO specifier for the GPIO that enables and disables
+ the clock generator.
+ maxItems: 1
+
+ vdd-supply:
+ description: handle of the regulator that provides the supply voltage
+
+required:
+ - compatible
+ - "#clock-cells"
+ - clock-frequency
+
+additionalProperties: false
+
+examples:
+ - |
+ clock {
+ compatible = "clock-generator";
+ #clock-cells = <0>;
+ clock-frequency = <1000000000>;
+ };
+...
--
2.39.2