GRUB2, without initrd.

[Yawning]

If you made it work with other boot loaders please help out

For what it's worth, GRUB2 can handle installing a DSDT override if configured to do so (acpi /boot/dsdt.aml).

There's a script floating around (I got the copy I used from https://blog.michael.kuron-germany.de/2011/03/patching-dsdt-in-recent-linux-kernels-without-recompiling/) to drop into /etc/grub.d so the entry persists through grub2-mkconfig, though it required a minor edit to work on Fedora.

The downside is that the only way to tell if it's working is to examing /sys/power/mem_sleep, but it saves the hassle of messing with cpio.

[dal00]

Interesting, this looks simpler. I can have a look in a couple of days perhaps.

[komali2]

Shit makes no sense, yo

I'll try to use my dumb webengineer brain to parse the above blog into steps that work on ubuntu 18, which comes with grub2

[Yawning]

1. Stick the patched DSDT in /boot (/boot/dsdt.aml).
2. Stick the script in /etc/grub.d (This is what I use on F28, YMMV).
3. Add mem_sleep_default=deep to the kernel command line (Edit /etc/default/grub).
4. Regenerate the grub.cfg file (Ubuntu seems to do this with update-grub).
5. Reboot.
6. cat /sys/power/mem_sleep should look like s2idle [deep].
7. Ignore the problem forever.

[komali2]

These instructions were clear, and I had no problem following them. Thank you for writing them out. Unfortunately, they did not work. I have no [deep] in my sys/power/mem_sleep, and attempting to add it manually causes "invalid argument" errors.

I might be incorrectly assuming that this fix works for thinkpad x1 yoga, the same as it works for thinkpad x1 carbon. Ah well.

[komali2]

I wonder if this is because I had to create the 01_acpi file in /etc/grub.d. I don't know much about anything, but all the other 00_whatever or 10_whatever files are green font colored in the terminal, and mine is white, like the sad little README off to the side :(

[komali2]

Oh, duh, stat on the file, shows Access: (0644/-rw-r--r--), while the 00_header file, for example, has Access: (0755/-rwxr-xr-x). Now I just need to learn enough about permission stuff to get them identical...

[dal00]

"sudo chmod 0755 yourfile" should do it! -- Sent from my Android device with K-9 Mail. Please excuse my brevity.

[komali2]

Haha damn, almost had you beat! I had gotten to the point where I was doing sudo chmod myfile 0755 and was trying to figure out the proper order! Thanks for the help :)

[komali2]

For others: last time, I didn't see the line Found custom ACPI table: .... which I thought was weird, cause I saw it in the script, but now I do, yay! So when you sudo update-grub, it should look like:

caleb@laptop:/etc/grub.d$ sudo update-grub
Generating grub configuration file ...
Found custom ACPI table: /boot/dsdt.aml
Found linux image: /boot/vmlinuz-4.15.0-29-generic

[komali2]

Huh, still didn't work, oh well, that was about as valiant an effort as I think is possible. I will monitor this repo to see what else crops up. Thanks @dal00 and @Yawning !

[ccressent]

Just a quick note to say that, using GRUB2 on Arch Linux, I've followed @Yawning's instructions and everything works perfectly fine!

~$ dmesg | grep -i "acpi: (supports"
[    0.557055] ACPI: (supports S0 S3 S4 S5)

~$ cat /sys/power/mem_sleep 
s2idle [deep]

Not sure about the downside @Yawning mentioned in his/her original post.

[fiji-flo]

Closing this, since Lenovo added S3 support.