I have a similar issue with a samsumg series 3 laptop with "VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] BeaverCreek [Radeon HD 6620G]" and "VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Seymour [Radeon HD 6400M/7400M Series]". after resume an external monitor show the system is still responsive.
BUT I can make the screen turn on after suspend with the next command:
sudo pm-suspend --quirk-test --quirk-s3-bios
so if you can try and this work maybe we can kick this issue.
I have a similar issue with a samsumg series 3 laptop with "VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] BeaverCreek [Radeon HD 6620G]" and "VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Seymour [Radeon HD 6400M/7400M Series]". after resume an external monitor show the system is still responsive.
BUT I can make the screen turn on after suspend with the next command:
sudo pm-suspend --quirk-test --quirk-s3-bios
so if you can try and this work maybe we can kick this issue.