Librem Mini v2 - Keyboard and mouse issues with KVM

[sienks]

I’m using a Librem Mini v2, connected via a TESmart KVM switch (model HKS0802A1U-AUBK) to swap between multiple computers.

When using the KVM with the Librem, I’m encountering the following issues:

• After some period of time using the Librem with the keyboard and mouse connected via the KVM the mouse and keyboard will become unresponsive. It could take 10 or 20 minutes for the issue to occur. Disconnecting and reconnecting the keyboard and mouse resolve the issue, but only temporarily, after the issue beings disconnecting and reconnecting will only work before the issue occurs again maybe 1 - 2 minutes later.
• In addition, a less common issue that sometimes occurs is a key on the keyboard becoming stuck, the key will repeat as if held down until I can interrupt the sequence by pressing another key.

Note:

• These problems do not occur when the keyboard and mouse are connected directly to the Librem.
• In addition these issues do not occur with other computers connected via the KVM, one of which being my laptop (Lenovo X1 Extreme Gen 2).
• The KVM has two dedicated keyboard and mouse ports which are emulated to support keyboard and mouse switching and addition to a USB port at the front. The issues seem to occur with both the USB port an the dedicated keyboard and mouse ports.

Current peripherals:

• Logitech G502 X PLUS LIGHTSPEED Wireless RGB Gaming Mouse (wireless)
• Das Keyboard 4 (wired)

Previously tested peripherals (same issues occurred):

• Logitech M720 Triathlon Mouse (wireless)
• Logitech G915 TKL LIGHTSPEED Wireless Mechanical Keyboard (wireless)

As stated these issues only occur with the Librem Mini, I have tested using both Fedora and QubesOS.

This feels like a firmware issue to me, is there anyway that I can test to confirm or get some more insight into whats going on?

Does anyone have any ideas?

[Skalman]

@sienks

Does anyone have any ideas?

One idea is to try looking at logs, things like “sudo journalctl” and “sudo dmesg” and see if there are clues there to what is going wrong, especially if there are log messages at the precise moment when things stop working.

[FranklyFlawless]

@jonathon.hall

[irvinewade]

@sienks

Does anyone have any ideas?

Are you in a position to (borrow a KVM switch to) test with a different make/model of KVM switch?

I have two sets of Linux computers that either have been or are still used via a KVM switch, and don’t experience problems, but I don’t have a Librem Mini and I don’t have a full KVM switch - I find it cheaper to use a separate video switch (HDMI) and USB switch, even though that means pushing two buttons to switch from one computer to another, albeit that sometimes I only want to switch the video anyway. (By definition therefore in my case, there are no dedicated keyboard and mouse ports, just a bunch of USB ports to switch across, which also include audio and/or video.)

Maybe a separate USB switch would be an affordable test, depending in part on how many computers you are switching between¹.

In my case, both mouse and keyboard are wired, and that eliminates the additional variable of how the receiver dongle handles the switching.

Does your KVM switch support having an external power supply and, if so, are you using it?

¹ Yes, I know that I could hunt up that model number in order to find out. Maybe you could include a product link.

[sienks]

Unfortunately no I cant get another KVM to test.

I originally thought it was just wireless receivers that caused the issue however my keyboard is wired and it stopped working along with the mouse yesterday.

Given that I have tried multiple keyboard and mouse combos, the same operating system across different computers with the KVM switch and the only computer that has issues is the Librem, I feel like speculating that its a firmware issue is a fair guess.

Yes it does have a power adaptor and im using it.

Here is a link:

4 Port Dual Monitor KVM Switch Kit HDMI 4K60Hz with EDID HKS0802A1U

[irvinewade]

@sienks

I feel like speculating that its a firmware issue is a fair guess

Fair enough. Or at least you appear to have solid fault isolation down to the Librem Mini, other than trying a different switch.

One other difference I note is that yours appears to be USB 2.0 only whereas my setup is USB 3.0 - but I don’t think that would make a difference.

Could it be some kind of powersave / standby / sleep scenario??

I guess I would be checking whether software and firmware on the Librem Mini are up to date.

[wctaylor]

Many months (maybe over a year) ago, I was also dealing with this issue. I spent some time iterating with @jonathon.hall to test various USB tuning parameters in the firmware, but I don’t think we ever fully resolved it, at least in my case.

This thread has some info:

Librem Mini v2: USB tuning preview, episode 3

I have a new USB tuning build for Librem Mini v2. As before, this is coreboot+SeaBIOS only for now, if it works out well it will go into a proper release for PureBoot. Also Mini v2 only at the moment, it’s likely this will apply to v1 also but I have not tested that yet. As always, use the preview branch’s coreboot_util.sh to flash: mkdir ~/updates cd ~/updates wget https://source.puri.sm/firmware/utility/-/raw/4.22.01-Purism-1-Preview-Mini-USB2-202405/coreboot_util.sh sudo bash coreboot_uti…

In my case, I think I decided I should try to replace the capacitor, as mentioned in this particular post within that thread:

Librem Mini v2: USB tuning preview, episode 3

@howil and others - this needs a hardware rework, change one capacitor. The ODM was very helpful in troubleshooting this, but we cannot address it in firmware since the tuning improvements above were not sufficient. Please contact support@puri.sm if you would like to discuss an RMA or out-of-warranty repair. If you are comfortable replacing an SMT capacitor, you can make the change below. This capacitor on the bottom of the board needs to be replaced with 22 uF 6.3V 0603 on affected devices. …

It’s a pretty low priority for me at this point, so I doubt I will get around to checking how things work with a different capacitor.

[sienks]

@Skalman @wctaylor below is a portion of the logs captured when the issue occurred:

In this instance, the issue lasted for approximately 10 seconds, during which the mouse and keyboard became unresponsive. This happened while using the KVM keyboard and mouse connected to the front USB 2.0 port of the Librem.

[ 4306.291132] usb 1-4.2: reset full-speed USB device number 3 using xhci_hcd
[ 4306.659145] usb 1-4.3: reset full-speed USB device number 4 using xhci_hcd
[ 4307.035232] usb 1-4.3: reset full-speed USB device number 4 using xhci_hcd
[ 4307.732106] usb 1-4.2: reset full-speed USB device number 3 using xhci_hcd
[ 4308.403251] usb 1-4.3: reset full-speed USB device number 4 using xhci_hcd
[ 4309.099252] usb 1-4.2: reset full-speed USB device number 3 using xhci_hcd
[ 4309.772180] usb 1-4.3: reset full-speed USB device number 4 using xhci_hcd
[ 4310.139070] usb 1-4.3: reset full-speed USB device number 4 using xhci_hcd
[ 4310.539149] usb 1-4.2: reset full-speed USB device number 3 using xhci_hcd
[ 4311.507262] usb 1-4.3: reset full-speed USB device number 4 using xhci_hcd
[ 4311.883245] usb 1-4.3: reset full-speed USB device number 4 using xhci_hcd
[ 4312.251337] usb 1-4.2: reset full-speed USB device number 3 using xhci_hcd
[ 4313.252303] usb 1-4.3: reset full-speed USB device number 4 using xhci_hcd
[ 4313.619331] usb 1-4.2: reset full-speed USB device number 3 using xhci_hcd
[ 4314.619180] usb 1-4.3: reset full-speed USB device number 4 using xhci_hcd
[ 4314.995354] usb 1-4.3: reset full-speed USB device number 4 using xhci_hcd
[ 4315.355172] usb 1-4.2: reset full-speed USB device number 3 using xhci_hcd
[ 4316.363274] usb 1-4.3: reset full-speed USB device number 4 using xhci_hcd
[ 4316.723343] usb 1-4.2: reset full-speed USB device number 3 using xhci_hcd
[ 4317.084135] usb 1-4.3: reset full-speed USB device number 4 using xhci_hcd
[ 4318.091261] usb 1-4.2: reset full-speed USB device number 3 using xhci_hcd
[ 4318.459195] usb 1-4.3: reset full-speed USB device number 4 using xhci_hcd
[ 4318.843240] usb 1-4.3: reset full-speed USB device number 4 using xhci_hcd
[ 4319.459221] usb 1-4.2: reset full-speed USB device number 3 using xhci_hcd
[ 4320.211236] usb 1-4.3: reset full-speed USB device number 4 using xhci_hcd
[ 4320.587249] usb 1-4.3: reset full-speed USB device number 4 using xhci_hcd
[ 4320.947156] usb 1-4.2: reset full-speed USB device number 3 using xhci_hcd
[ 4321.963311] usb 1-4.3: reset full-speed USB device number 4 using xhci_hcd
[ 4322.324201] usb 1-4.2: reset full-speed USB device number 3 using xhci_hcd
[ 4322.683228] usb 1-4.3: reset full-speed USB device number 4 using xhci_hcd
[ 4323.699356] usb 1-4.2: reset full-speed USB device number 3 using xhci_hcd
[ 4324.067361] usb 1-4.3: reset full-speed USB device number 4 using xhci_hcd
[ 4324.443987] usb 1-4.3: reset full-speed USB device number 4 using xhci_hcd

The issue occurred again later and did not resolve on its own while the KVM keyboard and mouse were connected to the USB 3.0 ports at the back of the Librem.

While I can’t say for certain, the issue appears to be more severe when using the USB 3.0 ports, please note during this both the keyboard and mouse are unresponsive.

In the second instance after a while the keyboard became responsive again but not the mouse, I performed a reboot via terminal, after the reboot the keyboard was working but not the mouse. The mouse however would work when connected directly to a Librem USB port, but when I plugged it back into the KVM USB port the mouse (and only the mouse) was unresponsive.

Any thoughts ?

[FranklyFlawless]

What boot firmware and version are you using?

[sienks]

@FranklyFlawless Pureboot 30

[FranklyFlawless]

I suggest contacting Purism:

• Contact - Purism user documentation

Use this quote as a basis for the email body:

@jonathon.hall

This capacitor on the bottom of the board needs to be replaced with 22 uF 6.3V 0603 on affected devices.

This change fixed the issue on both affected devices that I have with the current firmware release, no tuning changes were needed.

[wctaylor]

Unfortunately, I think your options are

1. Try to replace the capacitor yourself, as described in the thread I mentioned
2. (Maybe) Send the Mini back to Purism to see if they can replace the capacitor for you (I would expect this to take a very long time, given how busy Purism support often is, and I doubt it would be free)
3. Wait for a Mini v3, then buy that and hope the problem is fixed

I will add that I am not sure replacing the capacitor is even guaranteed to fix things. I think Jonathon or someone else at Purism would be more qualified to answer that. It is also not my intent to belittle Purism - the company and the support team both do great work! They just do really, really hard stuff, and so issues happen.

[sienks]

Thanks for your response.

1. I don’t really have the ability to do this, maybe finding a board repair shop is an option if I got instructions from purism.
2. I could but as you said time and cost are big factors here.
3. Honestly after all the issues I’ve encountered I cant see myself purchasing from Purism again. I understand issues occur but there have just been too many since purchase.

I’ll send an email to purism and I’ll include this thread, I hope in the meantime someone from purism comes across this thread with a solution.