[PATCH 00/17] Add an experimental driver for Intel NUC leds

From: Mauro Carvalho Chehab
Date: Sun May 16 2021 - 06:54:18 EST


Hi Greg,

This series add support for the LEDs found at Intel NUCs since
NUC version 6.

On several NUC models, the function of the LEDs are programmable,
which allow them to indicate several different hardware events.

They can even be programmed to represent an userspace-driven event.

Some models come with single colored or dual-colored LEDs, but
high end models have RGB LEDs.

Programming them can ether be done via BIOS or by the OS.

There are 3 different API types, and there is already some OOT
drivers that were written to support them, using procfs, each
one using a different (and IMO confusing) API.

After looking at the existing drivers and not liking the uAPI
interfaces there, I opted to write a new driver from scratch,
unifying support for all different versions and using sysfs
via the leds class.

It should be noticed that those devices use the Windows Management
Interface (WMI). There are actually 3 different implementations for it:

- one for NUC6/NUC7, which has limited support for programming just
two LEDs;
- a complely re-written interface for NUC8, which can program up to
seven LEDs, named version 0.64;
- an extended version of the NUC8 API, added for NUC10, called version
1.0, with has a few differences from version 0.64.

Such WMI APIs are documented at:
- https://www.intel.com/content/www/us/en/support/articles/000023426/intel-nuc/intel-nuc-kits.html
- https://raw.githubusercontent.com/nomego/intel_nuc_led/master/specs/INTEL_WMI_LED_0.64.pdf
- https://www.intel.com/content/dam/support/us/en/documents/intel-nuc/WMI-Spec-Intel-NUC-NUC10ixFNx.pdf

I wrote this driver mainly for my NUC8 (NUC8i7HNK), but I used a NUC6
in order to double-check if NUC6 support was not crashing. Yet, while
the NUC6 model I have accepts the WMI LED API, it doesn't work, as it
seems that the BIOS of my NUC6 doesn't let userspace to program the LEDs.

I don't have any devices using NUC10 API.

Due to the lack of full tests on NUC6 and NUC10, and because I
wrote a new uAPI that's different than the procfs-based ones found
at the OOT drivers, I'm opting to submit this first to staging.

This should allow adjusting the uAPI if needed, and to get feedback from
people using it on NUC6, NUC10 and on other NUC models that would be
compatible with it.

Mauro Carvalho Chehab (17):
staging: add support for NUC WMI LEDs
staging: nuc-wmi: detect WMI API detection
staging: nuc-wmi: add support for changing S0 brightness
staging: nuc-wmi: add all types of brightness
staging: nuc-wmi: allow changing the LED colors
staging: nuc-wmi: add support for WMI API version 1.0
staging: nuc-wmi: add basic support for NUC6 WMI
staging: muc-wmi: add brightness and color for NUC6 API
staging: nuc-wmi: Add support to blink behavior for NUC8/10
staging: nuc-wmi: get rid of an unused variable
staging: nuc-wmi: implement blink control for NUC6
staging: nuc-wmi: better detect NUC6/NUC7 devices
staging: nuc-led: add support for HDD activity default
staging: nuc-wmi: fix software blink behavior logic
staging: nuc-wmi: add support for changing the ethernet type indicator
staging: nuc-wmi: add support for changing the power limit scheme
staging: nuc-led: update the TODOs

MAINTAINERS | 6 +
drivers/staging/Kconfig | 2 +
drivers/staging/Makefile | 1 +
drivers/staging/nuc-led/Kconfig | 11 +
drivers/staging/nuc-led/Makefile | 3 +
drivers/staging/nuc-led/TODO | 8 +
drivers/staging/nuc-led/nuc-wmi.c | 2100 +++++++++++++++++++++++++++++
7 files changed, 2131 insertions(+)
create mode 100644 drivers/staging/nuc-led/Kconfig
create mode 100644 drivers/staging/nuc-led/Makefile
create mode 100644 drivers/staging/nuc-led/TODO
create mode 100644 drivers/staging/nuc-led/nuc-wmi.c

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2.31.1