Noticing everyone in this bug report has Intel + Radeon graphics, I tried disabling the Radeon. Simply running 'sudo rmmod radeon' after the laptop boots up with the stock 4.4 kernel allows it to properly sleep. Removing the kernel module causes kernel oops, but otherwise everything seems fine after unloading it. I've attached a dmesg showing the kernel module removal with the oops, and the successful sleep/wake that follows it. I've tried it several times and sleep/wake is working every time after removing radeon, and fails every time while radeon is loaded.
** Attachment added: "dmesg after removing radeon module" https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1566828/+attachment/4640297/+files/dmesg.txt -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1566828 Title: Suspension does not work, freezes the pc To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1566828/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs