Hi Jakub, These RGB LEDs have been part of the Time Card hardware since the original design, beside the four SMA connectors and the GNSS inputs. We never had the opportunity to add Linux driver support, so they have remained unused under Linux.
There is recurring confusion about which logical SMA number corresponds to which physical connector and how each connector is configured. The LEDs address a similar operational need to ethtool -p: they help an operator correlate a logical interface with the physical connector. Their colors can also represent the SMA input/output configuration and timing status, together with GNSS fix or lock status. This series exposes the LEDs through the standard LED class, avoiding board-specific raw I2C commands. The generic LED controller driver provides the standard interface, while the board-specific status policy remains outside that driver. The second GNSS LED supports the card variant with a second receiver. I should have stated this existing hardware and end-user use case explicitly in the cover letter. I will add it to the next revision. On Tue, Aug 18, 2026 at 9:56 AM Jakub Kicinski <[email protected]> wrote: > > On Fri, 14 Aug 2026 16:10:48 -0700 Ahmad Byagowi wrote: > > Add the generic LED and I2C-mux support needed to describe peripherals > > behind the FPGA I2C controller, then use it to instantiate the R4006 and > > Time Card V9 board topologies from software nodes. > > Ahmad, could you explain why? What are you going to do with these LEDs > as a end user? > > The influx of the LLM generated patches has a hugely negative impact on > the community. -- 73 With best wishes / Mit herzlichsten Grüßen Ahmad Byagowi, Ph.D., Dr. Techn., P.Eng. Phone: +1 (650) 924 6653 Please consider the environment before printing this e-mail.
