Rafael J. Wysocki wrote: > On Thu, Sep 8, 2022 at 8:05 AM Dan Williams <dan.j.williams@xxxxxxxxx> wrote: > > > > Robert Richter wrote: > > > A lookup of a host bridge's corresponding acpi device (struct > > > acpi_device) is not possible, for example: > > > > > > adev = ACPI_COMPANION(&host_bridge->dev); > > > > > > This could be useful to find a host bridge's fwnode handle and to > > > determine and call additional host bridge ACPI parameters and methods > > > such as HID/CID or _UID. > > > > When is this explicitly needed. "Could be useful" is interesting, but it > > needs to have a practical need. > > It is needed and it is present on x86 AFAICS (see my last reply in this thread). > > This seems to be addressing an ARM64-specific issue. > Ah, ok, thanks for pointing that out.