Comment 21 for bug 1661741

Exactly the same for me : E5470, with 4.15.0-30 and 3 month previous kernel
with lvm inside cryptsetup partition

Bios version: 1.18.6, EFI not secure mode, without legacy
latest intel ME update
SSD : Crucial MX100 CT512MX100SSD1 SATA 512GB with MU03 firmware

I discover this problem 3 month ago, it took me time before I link the problem to power cable,
suspend works only if power cable is not remove, even suspend battery only is not working.

I test 2 Dell idea: enable usb wake support and disable block sleep (C3 state) but no luck

I try post #4 solution: swap size is smaller than memory size so hibernate never works for me,
after removing all #4 change now suspend works without power cable

Thank you Jonathan