It's been an issue with this laptop since the day the laptop released, so there has never been a solution. testing the latest kernel is always what I do, so I can verify that 4.8-rc2 does not include a fix for this model.
** Tags added: kernel-bug-exists-upstream -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1613106 Title: Sony VAIO PCG-61A12L (VPCEG16FM) Intel Backlight Issue To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1613106/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs