Hi All, There are some problems with our handling of ACPI power resources that have accumulated over time or have never been addressed. First of all, the interface represented by acpi_power_resource_[un]register_device() doesn't really work as it should, so it needs to be redesigned (details in the changelog of patch [1/12]). Second, power resources really have to be treated in a special way by the ACPI namespace scanning code, because they may need to be ready to use as soon as they are discovered. Moreover, the are represented by struct acpi_device objects, so that they appear in sysfs along with "regular" ACPI device nodes, they really don't represent devices, so they need special configuration treatment in some cases. This special casing is obnoxiously present in scan.c, but if we accept the fact that power resources really are a special case, things can be simplified quite a bit (patch [3/12] with some preparations in [2/12]). If the above changes are made, then it turns out that the entire acpi_power_driver structure is not necessary any more and we don't need the device power states of power resources for anything (patches [4-5/12]). Moreover, ACPI power resources are supposed to be ordered. Namely, they have an attribute defining the order in which they are supposed to turned on and off. Currently, though, we don't take that attribute into accound, although we obviously should do that. After the previous changes that may be implemented at a relatively low cost (patch [6-7/12]). Patches [8-9/12] move code around and clean it up in preparation for patch [10/12], which consolidates the way in which power resources lists are extracted from the output of _PRW and _PR[0-3]. Patch [11/12] improves the handling of power resource initialization errors and patch [12/12] causes the system level attribute of wakeup power resources to be taken into account during device setup. All patches are on top of the git branch at: git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm.git linux-next Tested on HP nx6325 (and other boxes where ACPI power resources aren't used). Thanks, Rafael -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center. -- 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
