[PATCH v3 2/4] dt-bindings: leds: Add virtualcolor group dt bindings documentation.

Jonathan Brophy
2025-10-19T09:24:14Z

From: Jonathan Brophy <professor_jonny@hotmail.com>

Add device tree binding documentation for the virtual LED group driver
that implements virtual LED groups by aggregating multiple monochromatic
LEDs

Bindings for the virtual driver are not describing hardware LEDs they
describe virtual devices made from groups of hardware LEDs created from an array
of LED phandles.

Normally the device tree is used to describe hardware not virtual hardware
but it is particularly useful in situations where you require an LED to be a
specific color by mixing primary colors, such as multi element multi color LEDs
to be operated from a device tree binding.

It also becomes useful with multiple LEDs operating the same indicator such as
ring of light indicators where the LEDs are driven From different GPIO outputs
unifying the control that can give basic indication during system startup,
shutdown upgrade etc...

co-developed-by: Radoslav Tsvetkov <rtsvetkov@gradotech.eu>
Signed-off-by: Radoslav Tsvetkov <rtsvetkov@gradotech.eu>
Signed-off-by: Jonathan Brophy <professor_jonny@hotmail.com>
---
.../leds/leds-group-virtualcolor.yaml | 110 ++++++++++++++++++
1 file changed, 110 insertions(+)
create mode 100644 Documentation/devicetree/bindings/leds/leds-group-virtualcolor.yaml

diff --git a/Documentation/devicetree/bindings/leds/leds-group-virtualcolor.yaml b/Documentation/devicetree/bindings/leds/leds-group-virtualcolor.yaml
new file mode 100644
index 000000000000..f638bdd4d65e
--- /dev/null
+++ b/Documentation/devicetree/bindings/leds/leds-group-virtualcolor.yaml
@@ -0,0 +1,110 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/leds/leds-group-virtualcolor.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+title: virtualcolor LED group driver
+maintainers:
+ - Radoslav Tsvetkov <rtsvetkov@gradotech.eu>
+description: |
+ Implements virtual LED groups by aggregating multiple monochromatic LEDs.
+ Provides priority-based control for managing concurrent LED activation requests,
+ ensuring only the highest-priority LED state is active at any given time.
+properties:
+ compatible:
+ const: leds-group-virtualcolor
+ '#address-cells':
+ const: 1
+ '#size-cells':
+ const: 0
+patternProperties:
+ "^virtual":
+ $ref: leds-class-virtualcolor.yaml#
+required:
+ - compatible
+additionalProperties: false
+examples:
+ - |
+ #include <dt-bindings/leds/common.h>
+ #include <dt-bindings/gpio/gpio.h>
+
+ led-controller {
+ compatible = "gpio-leds";
+ led_red: led_red {
+ gpios = <&gpio0 10 GPIO_ACTIVE_HIGH>;
+ default-state = "off";
+ };
+ led_green: led_green {
+ gpios = <&gpio0 11 GPIO_ACTIVE_HIGH>;
+ default-state = "off";
+ };
+ led_blue: led_blue {
+ gpios = <&gpio0 12 GPIO_ACTIVE_HIGH>;
+ default-state = "off";
+ };
+ };
+
+ pwm-led-controller {
+ compatible = "pwm-leds";
+
+ led_1: led-1 {
+ color = <LED_COLOR_ID_RED>;
+ pwms = <&twl_pwm 0 7812500>;
+ };
+
+ led_2: led-2 {
+ color = <LED_COLOR_ID_GREEN>;
+ pwms = <&twl_pwmled 0 7812500>;
+ };
+
+ led_3: led-3 {
+ color = <LED_COLOR_ID_RED>;
+ pwms = <&twl_pwm 0 7812500>;
+ };
+
+ led_4: led-4 {
+ color = <LED_COLOR_ID_GREEN>;
+ pwms = <&twl_pwmled 0 7812500>;
+ };
+
+ };
+
+ virtual-led-controller {
+ compatible = "leds-group-virtualcolor";
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ virtual_red@0 {
+ reg = <0>;
+ function = LED_FUNCTION_VIRTUAL_STATUS;
+ color = <LED_COLOR_ID_RED>;
+ leds = <&led_red>;
+ priority = <2>;
+ };
+
+ virtual_yellow_mix@1 {
+ reg = <1>;
+ function = LED_FUNCTION_VIRTUAL_STATUS;
+ color = <LED_COLOR_ID_YELLOW>;
+ leds = <&led_green &led_red>;
+ pwm-leds-red = <&led_1 &led_2>;
+ pwm-leds-green = <&led_1 &led_3>;
+ priority = <1>;
+ };
+
+ virtual_white@2 {
+ reg = <2>;
+ function = LED_FUNCTION_VIRTUAL_STATUS;
+ color = <LED_COLOR_ID_WHITE>;
+ leds = <&led_red &led_green &led_blue>;
+ priority = <15>;
+ };
+
+ virtual_pwm_red@3 {
+ reg = <3>;
+ function = LED_FUNCTION_VIRTUAL_STATUS;
+ color = <LED_COLOR_ID_RED>;
+ pwm-leds-red = <&led_1 &led_3>;
+ priority = <1>;
+ };
+ };
--
2.43.0