Re: [PATCH 5/6] ACPI: Add support for native USB4 control _OSC

Hi,

On Tue, Jan 26, 2021 at 06:35:20PM +0100, Rafael J. Wysocki wrote:

quoted

+       capbuf[OSC_QUERY_DWORD] = 0;
+       capbuf[OSC_SUPPORT_DWORD] = 0;
+       capbuf[OSC_CONTROL_DWORD] = control;
+
+       status = acpi_run_osc(handle, &context);

This is the same _OSC that is evaluated in
acpi_bus_osc_negotiate_platform_control(), right?

Yes, but different UUID.

So shouldn't the capbuf[OSC_SUPPORT_DWORD] be whatever is negotiated
through acpi_bus_osc_negotiate_platform_control()?  At least that
would be consistent with acpi_pci_osc_control_set().

The ACPI 6.4 spec says that the support field for this _OSC is reserved
(table 6.14 in the spec). So as far as I can tell this is not the same
as what we pass for the platform _OSC.