enum vga_switcheroo_client_id — client identifier
enum vga_switcheroo_client_id {
VGA_SWITCHEROO_UNKNOWN_ID,
VGA_SWITCHEROO_IGD,
VGA_SWITCHEROO_DIS,
VGA_SWITCHEROO_MAX_CLIENTS
};
initial identifier assigned to vga clients.
Determining the id requires the handler, so GPUs are given their
true id in a delayed fashion in vga_switcheroo_enable
integrated graphics device
discrete graphics device
currently no more than two GPUs are supported