I am sorry but I have to return to this subject and remove the tick in the “solved” box.
According to Jack of the Radxa team:
This is implemented by the ADC monitoring the input voltage on the ROCK 5B.
Further info is supplied by the user amazingfate:
Sysfs is provided by kernel driver, no userspace program is necessary.
So it might be possible to see the usb-c input voltage after all. Could it be that the placement of that information in the /sys file system has changed in later kernels, such as the 6.8 I have?
I’ve seen that wiki page before but only glanced over it. There’s no product called Rock Pi 5.
Radxa produces the Rock 5A that is sized as a Raspberry Pi 5 and The Rock 5B (the one I have) at a pico-ITX size. Recently they have announced three more additions to the Rock 5 series; the Rock 5C and Rock 5C lite, both with a Raspberry Pi 5 size, and the Rock 5 ITX in a mini-ITX size.
Having just one wiki page for the Rock 5 series is a bit problematic as the hardware differs between the models. One example is that the Rock 5C Lite uses a RK3582 SoC, while the others use some variant of the 3588 chip.
So the mailing-lists offer something like a haystack situation. However, I did find the post that helped me get started. Sadly that user hasn’t published anything since.
But homework is homework, after all, so back to the haystack.
@hukka Um, no, not a haystack, that is were the openSUSE ARM developers hangout that bring the images to life that you installed, or create a bug report.
If the mailing-list references the HCL: Rock Pi 5 page then that leads to a dead end.
The link on that page leads to https://rockpi.org/ where the Rock Pi 5 product can’t be found.
The Radxa site is now actually located at http://radxa.com/
The Radxa site has a products page but there’s no product called Rock Pi 5
The specifications on the HCL page instead hint at the Rock 5A.
But there’s also a SBC called Rock 5B which is the one I have.
…and the new Rock 5C that soon will be followed by the cut-corner Rock 5C Lite.
Later this year Radxa will add a mini-ITX motherboard too, the Rock 5 ITX.
They’re all different and need separate HCL pages.
On top of that I don’t know enough to formulate what I am searching for. Yes, the input voltage is what I want to know, but how does the computer measure it and what process makes that measurement available? The suggestions I get from the Radxa Forum (from their Debian viewpoint) fail because the path to the information that I want doesn’t exist on my machine running Tumbleweed.
The latest comments from the Radxa Forum points at ACPI being the reason to why that folder inside of /sys doesn’t exist here. So I carry on, regrettably irritating people in the process, but slooowly getting there. …I hope.
And it all started with an innocent quest for the input voltage of the USB-c socket. Little did I know…
@hukka yes, for external hardware. In this case I’m using the GPS pps signal for chrony to use on a GPIO input and also telling it I have an RTC module for it to use to keep the hardware time current on shutdown/boot.
Yours is an actual module, how it gets activated on that hardware I have no idea…
So… I’m actually relieved that tumbleweed does most of the work by itself. Now I just have to figure out what makes the work and how… I have a headache.
If i run sensors as root I only get the data about the nvme device. I get the composite and two sensor readings. Nothing else.
I expected something like the sensors command to display the input voltage of the usb-c connector, but so far I only get a subset of the sensor data, a subset that doesn’t contain the information I want.
Using an external volt meter for usb-c is a possibility, but I wanted to know if the OS itself knows. The answer is yes but I don’t know how to see that information, at least not yet.