On Thu, Jun 18, 2020 at 3:05 AM Hans Verkuil <hverkuil-cisco@xxxxxxxxx> wrote: > > On 18/06/2020 10:59, Jeff Chase wrote: > > Hi Hans, > > > > We are using two of these in an Intel-based Chromebox. I see that the > > cros-ec and seco drivers just statically define the PCI BDF of the > > Intel graphics device for their boards. I don't see an example of ACPI > > passing this information. I can copy cros-ec and seco by adding a > > board table and then use the UID of each device to select the correct > > port. Adding board-specific configuration to the driver doesn't seem > > ideal but I'm not sure what the proper way to pass this using ACPI is. > > You are right, it's not ACPI, it's using DMI matching. > > I have zero knowledge about ACPI, so I have no idea if there is some standard > method of retrieving this association via ACPI. I'm not very familiar with ACPI either. I looked for but did not find an ACPI equivalent of_get_mac_address(). I believe it's possible to reference the PCI node but it would take a bit of work on both the coreboot and linux side. > > This particular chip can actually be used both with DMI matching but also > on an ARM with device tree, but since you can't test this on an ARM board, > there is no point in adding support for that. > > However, compared to the cros-ec and seco drivers you can do something a bit > different here: those drivers just return -ENODEV if there is no match, but > since this driver reads the EDID it can just continue as long as it does not > set the CEC_CAP_CONNECTOR_INFO capability. Is it necessary to add support if we don't set CEC_CAP_CONNECTOR_INFO? Thanks, Jeff
