[PATCH v7 1/3] dt-bindings: pwm: add support for AE350 PWM controller

From: Ben Zong-You Xie <[email protected]>

The ATCPIT100 is a set of compact multi-function timers, which can be
used as pulse width modulators (PWM) as well as simple timers.
ATCPIT100 supports up to 4 PIT channels, and each PIT channel may be
configured as a simple timer or PWM, or a combination of the timer and
the PWM. This IP block is a core component of the Andes AE350 platform,
which serves as a reference architecture for SoC designs. The QiLai SoC
also integrates this controller.

The binding introduces the following compatible strings:
- "andestech,qilai-pwm": For the implementation integrated into the
  Andes QiLai SoC.
- "andestech,ae350-pwm": As a fallback compatible string representing
  the base IP design used across the AE350 platform architecture.

Reviewed-by: Rob Herring (Arm) <[email protected]>
Signed-off-by: Ben Zong-You Xie <[email protected]>
---
 .../bindings/pwm/andestech,ae350-pwm.yaml          | 61 ++++++++++++++++++++++
 1 file changed, 61 insertions(+)

diff --git a/Documentation/devicetree/bindings/pwm/andestech,ae350-pwm.yaml b/Documentation/devicetree/bindings/pwm/andestech,ae350-pwm.yaml
new file mode 100644
index 000000000000..287f3c62965f
--- /dev/null
+++ b/Documentation/devicetree/bindings/pwm/andestech,ae350-pwm.yaml
@@ -0,0 +1,61 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/pwm/andestech,ae350-pwm.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Andes PWM controller on AE350 platform
+
+description:
+  This controller has 4 channels and two clock sources. Each channel can
+  switch the clock source by programming the corresponding register.
+
+maintainers:
+  - Ben Zong-You Xie <[email protected]>
+
+allOf:
+  - $ref: pwm.yaml#
+
+properties:
+  compatible:
+    oneOf:
+      - items:
+          - enum:
+              - andestech,qilai-pwm
+          - const: andestech,ae350-pwm
+      - const: andestech,ae350-pwm
+
+  reg:
+    maxItems: 1
+
+  "#pwm-cells":
+    const: 3
+
+  clocks:
+    items:
+      - description: APB bus clock
+      - description: External clock
+
+  clock-names:
+    items:
+      - const: pclk
+      - const: extclk
+
+required:
+  - compatible
+  - reg
+  - "#pwm-cells"
+  - clocks
+  - clock-names
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    pwm@f0400000 {
+        compatible = "andestech,ae350-pwm";
+        reg = <0xf0400000 0x100000>;
+        #pwm-cells = <3>;
+        clocks = <&pclk>, <&extclk>;
+        clock-names = "pclk", "extclk";
+    };

-- 
2.34.1