My father uses Ubuntu for his Dell 7530 and I'm asking this question on his behalf. He recently upgraded to Ubuntu 20.04 and found that the monitor for the laptop doesn't turn back on when the laptop is closed and then reopened.
When the sleep button and power button is tapped, the screen turns off but the power button light doesn't change or blink to indicate sleep mode.
Nothing wakes up the laptop or turns the screen back on, not pressing power, spacebar, switch screen buttons, none of the function keys to get into the terminal mode, nothing. The only way to get the screen back is to perform a hard reset.
Here's what I've done to try to solve this, with no success:
- Upgraded to 20.10 and Kernel 5.8 to see if it's a kernel issue
- Changed all sleep directives in /etc/systems/logins.cond to ignore
- Disabled sleep mode in the BIOS (doesn't solve the problem but does stop the screen from turning off when the screen is closed or power button is used)
- Removed gnome-tweak-tool because it has the ignore sleep mode extension.
- Set grub boot property mem_sleep_default to all of the various states
I feel as though ignoring the sleep mode isn't really a solution to the screen problem, but it at least prevents it from happening if the monitor closes. I'd like to get the screen to turn back on or sleep mode to work properly.
One thing I should note is that when I tried pressing the volume up buttons once while the screen was off I could hear a ping tone, as if the volume was being affected, but I tried the same thing a few more times without the same result. I'm not certain if the OS is still running while the screen is off.
I can provide additional logs in a few days. I would be happy to provide anything I can.