<html> <head> <base href="https://bugs.freedesktop.org/"> </head> <body> <div> <a class="bz_bug_link bz_status_NEW " title="NEW - [NVC1] HDMI audio device only visible after rescan" href="https://bugs.freedesktop.org/show_bug.cgi?id=75985#c79">Comment # 79</a> on <a class="bz_bug_link bz_status_NEW " title="NEW - [NVC1] HDMI audio device only visible after rescan" href="https://bugs.freedesktop.org/show_bug.cgi?id=75985">bug 75985</a> from <a class="email" href="mailto:dan@reactivated.net" title="Daniel Drake <dan@reactivated.net>"> Daniel Drake</a> <pre>Thanks, you're right, the value changes based on HDMI connector status. So for this platform, \_SB.PCI0.PEG0 has a PG00 PowerResource that will set the magic bit in _ON, and likewise \_SB.PCI0.PEG0.PEGP has a _PS0 that will set the bit too. This all sounds like it should set the appropriate state at boot time, but I wouldn't expect these methods to be called when the HDMI connector is hotplugged. And I can't see any linkage to anything more dynamic like _DSM. Indeed booting Linux with HDMI already connected, the HDMI audio PCI device appears. Same on Windows, testing without the nvidia driver installed. I used the Clover UEFI bootloader to boot windows with a custom DSDT, modified the GGIV() function to always return zero (disconnected) for this GPIO. Then booting Windows with HDMI connected, the PCI device no longer appears. Then I installed the Nvidia windows driver. Connecting HDMI either at boot or later, the HDMI audio device appears on the PCI bus. Conclusion: The nvidia windows driver directly controls the magic bit here, triggering a PCI bus rescan too, without relying on ACPI.</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the assignee for the bug.</li> </ul> </body> </html>