> On Thu, 2006-08-31 at 17:06 -0600, Bjorn Helgaas wrote: >> Problem 1: acpi_reserve_io_ranges() needs to return an acpi_status >> like AE_OK or AE_CTRL_TERMINATE, not a -EINVAL. > > Sure great sounds. I understand AE_OK is a 0 return so I can change it > to AE_CTRL_TERMINATE. I don't want acpi_reserve_io_ranges to return a > happy state when if finds a resource type is doesn't know. Except that when the motherboard driver claims a device, it really should claim all the resources used by the device. It currently only claims I/O port resources, but I think it should also claim MMIO resources. Otherwise, the system resource accounting is screwed up, and resources consumed by the motherboard device could be mistakenly allocated to another device. > Kame (who helped me greatly in tracking down the source my troubles) > thinks that the root cause is that the device (my memory_device) has > both a _HID and _CID. The driver for _HID is different for _CID and the > driver for _CID is found before _HID and I pass the wrong device up the > chain. Ok, this is starting to make sense. It sounds like your memory device has _HID of PNP0C80 and _CID of PNP0C01 (or PNP0C02). The current ACPI driver binding algorithm in acpi_bus_find_driver() looks at each driver, checking whether it can match either the _HID or the _CID of a device. Since we try the motherboard driver first, it matches the memory device _CID. I couldn't find a specific reference in the spec, but this seems intuitively sub-optimal. It seems like it'd be better to look first for a driver that can claim the _HID (which is more specific), and only fall back to checking the _CIDs if no _HID-specific driver is found. This looks fairly easy to do in ACPI. Not so easy in PNPACPI, since I don't think PNP has the concept of _HID vs _CID. Maybe Len will chime in with an opinion. Bjorn - To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
