[systemd-devel] Alienware graphics amplifier scancodes

[Alexander E. Patrakov]

28.05.2015 01:59, Mario Limonciello wrote:
> Hi,
>
> Some Alienware notebooks and desktops support an external graphics
> housing called the "Alienware Graphics Amplifier". It allows the usage
> of a larger or more modern graphics card than your gaming PC would
> already support.  In order to provide a good experience, systems that
> support it can provide notification to the OS via the scancodes on the
> the keyboard controller of events related to the cable.
>
> The following 4 events are supported (and the presumed OS response):
> * Cable plugged in (An app on the existing display or terminal would
> tell the user to reboot the system to activate)
> * Undock cable pressed (An app would let the user know to reboot the
> system to complete undock process; also when supported by GFX driver,
> driver can clean up and work without a reboot)
> * Undock hotkey pressed (Same result as undock cable expected)
> * Surprise removal of cable (System immediately reboots).

OK, so you have described GPU hotplug in detail. Please note that 
Alienware is not the only system that has a hot-pluggable GPU. My 
laptop, Sony VAIO VPC-Z23A4R, manufactured in 2012, also has a similar 
facility (the AMD GPU, including two additional outputs, is in the 
docking station), but AFAIK it is not based on scancodes. So maybe it 
makes sense to unify handling of the "Undock" buttons on these devices. 
Feel free to contact me via email or XMPP (same address) so that we can 
figure out how to make this possible.

P.S. Under Windows 7, if the dock station is configured to be used for 
additional outputs only, it handles both docking and undocking without a 
reboot.

-- 
Alexander E. Patrakov