Hi, On 1/12/22 09:33, Wolfram Sang wrote: > 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@xxxxxxx/ > > 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. I expect host-notify to use IRQ7 too, but that it first needs to be enabled by poking some registers in the SMBUS controller. Regards, Hans