On Saturday 14 April 2018 13:17:11 Lukas Wunner wrote: > On Sat, Apr 14, 2018 at 12:49:50PM +0200, Pali Rohár wrote: > > On Saturday 14 April 2018 12:45:12 Lukas Wunner wrote: > > > On Thu, Apr 12, 2018 at 10:15:41PM +0800, Kai-Heng Feng wrote: > > > > Do you have any suggestion to check if it connects to the system via > > > > Thunderbolt? > > > > > > Just use pci_is_thunderbolt_attached(), introduced by 8531e283bee6, > > > like this: > > > > > > if (check_dell_switchable_gfx(pci) && !pci_is_thunderbolt_attached(pci)) > > > > And what about PCI-e device attached to ExpressCard slot? > > I don't know of a bullet-proof way to recognize those. In theory > one could check if the PCIe port above the GPU is a non-hotplug > root port, but I think there are machines with hotplug capable > root ports with GPUs below them that aren't actually removable. > > However I think ExpressCard-attached GPUs were rare, much less ones > with integrated HDA controller, so in reality that's probably a > non-issue. Hm... maybe another idea: Is it possible to detect which audio pci device belongs to graphics card via vga_switcheroo? Currently, looking at output it is same PCI device as graphic card, just different PCI function. -- Pali Rohár pali.rohar@xxxxxxxxx
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