Hi Mario, thanks for joining the discussion! > 1) Systems returning SMBUS address 0xff > > The address can be potentially be returned using port I/O or it can be done > using MMIO. > > There is already a thread in process to add support for MMIO, but last I > heard it's waiting for review comments. > > https://lore.kernel.org/all/20210715221828.244536-1-Terry.Bowman@amd.com/ This thread is under active discussion again. > Now something else interesting - the SMBUS controller in these laptops often > is listed in the ACPI tables on IRQ7 with a _HID of SMB0001. IIRC tests done by Miroslav showed that interrupt 7 was used for completing SMBus Block transfers and alike, but not for HostNotify. He suspects this is wired via GPIO somehow. Would be really cool if we can fix the bugzilla entry you mentioned as well during all this! Happy hacking, Wolfram