Lenovo Yoga 20CD Suspend to Ram

[t4thfavor]

I have a Lenovo Yoga 20CD with an I7 and 8GB ram. It suffers from Lenovo not enabling S3 in the bios, so it won't properly suspend.

When I suspend it will act like it's going to behave, the LED will start to "breathe", and then the whole system will just spontaneously wake up. I played with enabling s2idle, but that just kills the battery in like 2 hours.

The weird thing I'm coming to post and get information on is that when I enable s2Idle, then open a root terminal and change s2Idle to deep, and then suspend, it works perfectly. The LED breathes, the fans are off, everything is great until I wake it up, and try to suspend again.

I'm changing the /sys/power/mem_sleep setting using this command:

Code: Select all

cat  s2idle > /sys/power/mem_sleep
cat deep > /sys/power/mem_sleep

EDIT: The working process involves suspending to s2dle waking up, switching to deep, then suspending again using pm-suspend. So weird...

So I know S3 is working, but how do I make it work each time instead of just once?

The OS is 20.2 Uma, and it's a fresh install from about a week ago. I can post output from Journalctl if anyone is interested in what is happening.

TIA

[Pjotr]

Is there a BIOS update available? If so, apply it and test.

[t4thfavor]

There is not, I am on 1.34 bios which was released in April of 2021. I flashed it a day or so ago and there is still no S3 power options in the bios.

Suspending to s2Idle or shallow before switching to deep and issuing the pm-suspend command seems to be the silver bullet, I just wish I knew what was wrong as that's very inconvenient.

[Pjotr]

Please generate an overview of your system like this:

- Launch a terminal window (this is how to launch a terminal window);

- Make the terminal window full screen, to avoid chopped lines;

- Copy/paste this command into the terminal:

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inxi -Fxpmrz

(if you type: the letter F is a capital letter, and don't omit the space after inxi!)

Press Enter.

Copy/paste the output in your next message.

[t4thfavor]

I did a bad thing and reloaded it with Debian 11, it still does the same thing. I'm going to try a few other distros before I come back and follow through on this thread.

Thanks for your help so far.

[SMG]

I did a bad thing and reloaded it with Debian 11, it still does the same thing. I'm going to try a few other distros before I come back and follow through on this thread.

Thanks for your help so far.

I recommend you check the Lenovo community site for info and advice regarding this. Using S2idle rather than S3 is something which I understand to be a changed prompted by Windows requirements. This has been implemented on a number of laptops from many different manufacturers. The Lenovo forum would be more likely to be able to give you specifics about your particular model. (Many people with Lenovos use Linux-based distros, so there is a lot of info about Linux-based distro installs available on that site.)

[t4thfavor]

Been there already. They say it's not possible to support S3 because of the bios. And they won't release the bios that has S3 options enabled because it's not on their Linux compatibility list (the laptop)

I know that is incorrect because I can reliably trick the system into a very good S3 state and it comes back from said state flawlessly every time.

I have a post in the thread on the lenovo forum as well describing my "workaround" and I'll see what they say about it.

[SMG]

They say it's not possible to support S3 because of the bios. And they won't release the bios that has S3 options enabled because it's not on their Linux compatibility list (the laptop)

That is an interesting statement. Seems to fit in with the theory that it may be a Microsoft requirement to have S3 disabled.

I know that is incorrect because I can reliably trick the system into a very good S3 state and it comes back from said state flawlessly every time.

There may be something specific in the sequence you are using which is getting devices to power down that would not otherwise power down. I do not yet know enough about the synergy between the ACPI in the firmware (UEFI) and the ACPI settings the kernel uses to be able to give you a theory of what is happening.