From: Alexander Sverdlin <[email protected]> Extend the TI LP8864/LP8866 device-tree binding to support backlight class properties alongside the existing LED class child node.
This is a preparatory change for converting the LP8864 driver from a pure LED class driver to additionally register a backlight class device, motivated by a use case on a hot-pluggable segment of an I2C bus. The generic led-backlight driver (led_bl.c) is a platform driver and thus inherently non-hotpluggable, which makes it unsuitable for hardware topologies where the backlight controller resides on a hot-pluggable I2C bus segment. By making the LP8864 driver itself register a backlight class device, it becomes a native I2C driver that properly supports hot-plug/unplug events. The binding is updated to: - Reference backlight common.yaml at the top level, making default-brightness and max-brightness valid optional properties - Make the "led" child node optional rather than required, since the backlight class device is now the primary interface - Use unevaluatedProperties instead of additionalProperties to properly allow properties inherited from the referenced common schema The LED child node is preserved for backward compatibility with existing device-trees. No in-tree device-trees reference this binding, so this change has no impact on existing mainline users. Signed-off-by: Alexander Sverdlin <[email protected]> --- .../bindings/leds/backlight/ti,lp8864.yaml | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) diff --git a/Documentation/devicetree/bindings/leds/backlight/ti,lp8864.yaml b/Documentation/devicetree/bindings/leds/backlight/ti,lp8864.yaml index d44232d462bde..11d7e3840c6fb 100644 --- a/Documentation/devicetree/bindings/leds/backlight/ti,lp8864.yaml +++ b/Documentation/devicetree/bindings/leds/backlight/ti,lp8864.yaml @@ -4,7 +4,7 @@ $id: http://devicetree.org/schemas/leds/backlight/ti,lp8864.yaml# $schema: http://devicetree.org/meta-schemas/core.yaml# -title: Texas Instruments - LP8864/LP8866 4/6-Channel LED Driver family +title: Texas Instruments - LP8864/LP8866 4/6-Channel LED Backlight Driver family maintainers: - Andrew Davis <[email protected]> @@ -21,6 +21,9 @@ description: | https://www.ti.com/product/LP8866-Q1 https://www.ti.com/product/LP8866S-Q1 +allOf: + - $ref: common.yaml# + properties: compatible: const: ti,lp8864 @@ -36,9 +39,15 @@ properties: vled-supply: description: LED supply + default-brightness: + maximum: 65535 + + max-brightness: + maximum: 65535 + led: type: object - $ref: common.yaml# + $ref: /schemas/leds/common.yaml# properties: function: true color: true @@ -50,9 +59,8 @@ properties: required: - compatible - reg - - led -additionalProperties: false +unevaluatedProperties: false examples: - | -- 2.54.0
