On Thu, Aug 05, 2021 at 04:04:03PM +0200, Oliver Neukum wrote: > Hi, > > I am trying this on a new laptop, but I am getting a result I do not > understand. > ucsi_acpi_probe() is called, but ucsi_register() fails with -ENODEV, > because ucsi->version is 0. > > If I dump the ucsi_acpi buffer I get: > > 00 00 00 00 02 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > > And, frankly I do not understand that. Why have the ACPI device > but show version number 0? Because of BIOS bugs. Ideally we should be able to rely on the _STA method of the ACPI device, but unfortunately with UCSI we can't rely on that alone. On some systems the BIOS claims that the device is enabled (based on _STA) even when the platform doesn't actually support UCSI at all. If you remove the check, does the driver work? Br, -- heikki
