Hi Marek, Em Wed, 19 May 2021 09:57:13 +0200 Marek Behún <kabel@xxxxxxxxxx> escreveu: > We have multicolor LED framerwork in Linux. This should be implemented > via that framework. Please do not implement your own way for RGB leds. > > Marek I saw the multicolor LED framework, but IMO it won't fit here. See, Linux doesn't have direct access to the LED. The access is provided via ACPI WMI. The way BIOS reports the type of the led is via a bitmap flag. So, the same LED can be represented with either single-color or multi-color one. See: https://www.intel.com/content/dam/support/us/en/documents/intel-nuc/WMI-Spec-Intel-NUC-NUC10ixFNx.pdf Table 2.2 LED Color Type Bit Number Type 0 Dual-color Blue / Amber 1 Dual-color Blue / White 2 RGB-color 3 Single-color LED Also as each NUC can support up to 7, and they may have a mix of single color, dual color and RGB LEDs, if we would use the multicolor class for the colored ones, that would mean that the code will need to be duplicated, as, depending on what the BIOS reports, the LED would need to be exposed either as via led-multicolor-class or as leds-class. Worse than that, there's even a WMI command that would allow to "switch LED type" (see page 8). On other words, the BIOS can expose a "virtual" single-color LED, but actually implemented in hardware using a RGB one, and this can be changed in real time. (note: I didn't implement support yet for this, as the hardware I have doesn't seem to support the "switch LED type" command). Thanks, Mauro
