Some devices use PCA963x controllers to drive RGB LEDs, where
multiple PWM channels correspond to a single logical LED. Add
support for grouping such channels into a multicolor LED device,
using the LED multicolor class framework.

The DT bindings are extended to describe these groupings via a
multi-led@N node with sub-nodes representing individual color
channels. This follows conventions used by other multicolor LED
drivers, while maintaining full backward compatibility with
existing single-color LED definitions.

The PCA963x driver is updated accordingly to detect these grouped
definitions and register multicolor LEDs.

Finally, the Monaco Arduino Monza device tree is updated to expose
the onboard MCU-controlled LEDs (compatible with PCA9635). The MCU
manages four RGB LEDs mapped to channels 0–11, which are described
using the new multicolor bindings.

Signed-off-by: Loic Poulain <loic.poulain@oss.qualcomm.com>
---
Changes in v3:
- Add color to required multi-color leds (sashiko/Conor)
- Bounded registers value for nested led subnodes (sashiko/Conor)
- Add fix for PCA6535 reg limit (extend it to spec)
- Link to v2: https://lore.kernel.org/r/20260701-monza-leds-v2-0-c1be0b472926@oss.qualcomm.com (local)

Changes in v2:
Changes in v2:
- bindings: Reworded commit message to explain the motivation (Krzysztof)
- bindings: Kept the "^led@..." pattern and modeled multicolor groups
  via a dedicated "^multi-led@..." subtree.
- dts: Renamed node from "leds-controller@22" to "led-controller@22"
  and dropped the unused label. (Konrad).
- dts: Moved "reg" to directly follow "compatible" (Konrad).
- dts: Fixed unit addresses to lowercase hex (sashiko).
- Fixed checkpatch issues
- Link to v1: https://lore.kernel.org/r/20260629-monza-leds-v1-0-0cf7c0a7dc14@oss.qualcomm.com (local)

---
Loic Poulain (4):
      dt-bindings: leds: nxp,pca963x: fix reg maximum for pca9635
      dt-bindings: leds: nxp,pca963x: add multicolor LED support
      leds: pca963x: add multicolor LED class support
      arm64: dts: monaco-arduino-monza: microcontroller LEDs

 .../devicetree/bindings/leds/nxp,pca963x.yaml      | 116 ++++++++++++++++++-
 arch/arm64/boot/dts/qcom/monaco-arduino-monza.dts  | 110 ++++++++++++++++++
 drivers/leds/Kconfig                               |   1 +
 drivers/leds/leds-pca963x.c                        | 126 ++++++++++++++++++---
 4 files changed, 333 insertions(+), 20 deletions(-)
---
base-commit: dc59e4fea9d83f03bad6bddf3fa2e52491777482
change-id: 20260629-monza-leds-c292e68c9a49

Best regards,
-- 
Loic Poulain [off-list ref]