On Wed, Jan 18, 2023 at 02:40:00PM +0100, Krzysztof Kozlowski wrote:

On 18/01/2023 14:10, Jianhua Lu wrote:

quoted

Add Kinetic KTZ8866 backlight binding documentation.

Signed-off-by: Jianhua Lu <lujianhua000@gmail.com>
---
Changes in v2:
  - Remove "items" between "compatible" and "const: kinetic,ktz8866"
  - Change "additionalProperties" to "unevaluatedProperties"

Changes in v3:
  - Add Krzysztof's R-b

Changes in v4:
  - Drop Krzysztof's R-b
  - Add some new properties

Changes in v5:
  - Add missing enum under property description.
  - Rename uncorrect properties.

Changes in v6:
  - Correct wrong property suffix and description.

 .../leds/backlight/kinetic,ktz8866.yaml       | 59 +++++++++++++++++++
 1 file changed, 59 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/leds/backlight/kinetic,ktz8866.yaml

diff --git a/Documentation/devicetree/bindings/leds/backlight/kinetic,ktz8866.yaml b/Documentation/devicetree/bindings/leds/backlight/kinetic,ktz8866.yaml
new file mode 100644
index 000000000000..ca0deba14523
--- /dev/null
+++ b/Documentation/devicetree/bindings/leds/backlight/kinetic,ktz8866.yaml

@@ -0,0 +1,59 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/leds/backlight/kinetic,ktz8866.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Kinetic Technologies KTZ8866 backlight
+
+maintainers:
+  - Jianhua Lu <lujianhua000@gmail.com>
+
+description: |
+  The Kinetic Technologies KTZ8866 is a high efficiency 6-sinks led backlight
+  with dual lcd bias power.
+  https://www.kinet-ic.com/ktz8866/
+
+allOf:
+  - $ref: common.yaml#
+
+properties:
+  compatible:
+    const: kinetic,ktz8866
+
+  current-num-sinks:
+    description: Number of LED current sinks.
+    enum: [1, 2, 3, 4, 5, 6]
+
+  current-ramping-time-ms:
+    description: LED current ramping time in milliseconds.
+    enum: [2, 4, 8, 16, 32, 64, 128, 192, 256, 320, 384, 448, 512, 576, 640]
+
+  led-ramping-time-ms:
+    description: |
+      LED on/off ramping time in milliseconds, note that the case 0 will be mapped
+      to 512μs because ktz8866 can't ramp faster than it.

Aren't you just missing supplies here and their ramp up time?

backlight ic supply bias power to panel, but downsteam devicetree adds power supplies node to panel node, 
so I'm not sure if need to add power supplies to backlight node.

quoted

+    enum: [0, 1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096, 8192, 16384]
+
+  enable-lcd-bias:
+    description: Set if we want to output bias power supply for LCD.

Is it a generic property? I don't see any other users, so this looks
device specific thus needs vendor prefix.

This applies to all of the properties. They might be generic or might
not, I don't know the backlight hardware that much.

It surely is device specific, thanks.

quoted

+    type: boolean
+
+required:
+  - compatible
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    backlight {
+        compatible = "kinetic,ktz8866";
+
+        pinctrl-names = "default";
+        pinctrl-0 = <&bl_en_default>;
+
+        current-num-sinks = <5>;
+        current-ramping-time-ms = <128>;
+        led-ramping-time-ms = <1>;
+        enable-lcd-bias;
+    };

Best regards,
Krzysztof