Wifi and camara switches

Those switches are not power lines that kill power to the component or the data line, they are just arbitrary switches that the os checks just like a software switch, so to me it seems it defeats the purpose of what they are for, which is incase your laptop is hacked at least they can not see you and because of the power failure the driver will log to the kernel log and now you know you are hacked and some one is trying to view you. At which point you can revert the system to a state that may not be hacked. Those switches need to be either, power lines, data lines, or switches that release relays and cut power. Since power is intirrupted the driver for the camera or wifi will log to kernel and you will see that some one is poking around.

I am not sure which devices you are talking about here, but if you are referring to the Librem14 or the Librem5 phone then I can inform you that in these we actually do sever the power to the respective device using the kill switches and not just flip the #disable line as most other do. When flipping the kill switches in our L14 and L5 you will notice that these devices (like WiFi, Bluetooth, cellular modem etc.) actually disappear from the system (PCIe, USB, SDIO). They are off and no software can re-enable them (except that software control a robot finger that flips the kill switch again :wink:


  • hks wwan & wlan/bt upper right corner
  • hks camera in the middle a bit to the right margin

All of them cutting power lines.


Well, the OP did write “laptop” so I assumed Librem 14, but for the Librem 5, the actual schematics are even more definitive than the block diagram.

For the Librem 5 WiFi and modem hardware kill switches, you can see the connection to their respective AP2281 load switches, cutting the 3.3V power into the respective M.2 modules. (So I suppose even if you have replaced the M.2 modules with suitably-keyed alternative modules of any type, the hardware kill switch will still kill the damn thing.)

That gave me a chuckle. So when is the Librem Robot Finger going to be available? I think we all have some non-automated hardware where that would be useful.


Especially if it’s the robot’s middle one.


I was asking about the purism laptop not the phone. Reason I say this there was a video made where an individual flips the switch for the camara and takes 3 seconds of feed until it shuts down. A switch that carries power to the chip would shut the camara of instantaneously.

Can you find that video?

Keep in mind that the video feed keeps getting processed before it’s displayed. It’s typically less than 3 seconds, but if you try hard enough, even 3 seconds of delay are achievable!

Which Librem laptop are you referring to? The Librem 14 has better kill switches than the older Librem laptops (Librem 13 & 15). See this post.

From the post:

Sorry, misinterpreted your request then. I don’t know the resources for the Librem14(?) notebook.

If I’d not trust the marketing promises I’d just open up the device and measure the power connection to the wifi/bt module. Might be a bit harder to do that for the mic…

I’d be interested in that video, also.

here is the video of the switch being used and taking seconds meaning the bios probably looks at it as an interrupt and is not a kill switch.

How about the camara cause he hit the kill switch https://www.youtube.com/watch?v=hVcJgCvFuWo&t=15s and took three seconds which seems very similar to the way that you used to send the m2 shutdown.

It could also be the amount of time it takes the camera to run out of juice.

Cool video :slight_smile: Looks like the kill switches worked.

In the video the guy is using a Librem 13, with the older kill switches.

I bought a Librem 14, but that was a present for my oldest son. He’s moved out, so maybe I can test out the camera kill switch when he visits. He comes over quite often for game night :slight_smile:

… which makes the video obsolete. The Librem 13 is not even sold any more. The video needs to be redone using the Librem 14.

However the camera hardware kill switch probably hasn’t changed i.e. just cuts the power as it always did.

There is a range of subtlety involved in how quickly the switch takes effect:

  • the load switch may have an intentional delay (and the exact choice of component will determine the delay, but the delay would be low in human terms and high in computer terms e.g. 1 ms)
  • circuits often have stored energy and it takes a little while for the energy to dissipate once power is no longer applied
  • if the video stream (or an audio stream) is being encoded in software then a typical codec always introduces a delay
  • any other delays in the video / audio software pipeline

A robot finger that flips the kill switch…

Yes, Google will send out an Arnold Schwarzenegger looking T-1000 robot that breaks down your door and says “give me your phone”. He flips on all of your kill switches and says “if you turn them off again, I’ll be back”.

The Ultimate Machine. This unique feature would increase the L5’s volume. Will Purism make a dedicated device named “Librem Kill”? :smiley:


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