Bug 15373 - Bogus modalias entries in sysfs for sub devices
Summary: Bogus modalias entries in sysfs for sub devices
Status: CLOSED DOCUMENTED
Alias: None
Product: ACPI
Classification: Unclassified
Component: Config-Hotplug (show other bugs)
Hardware: All Linux
: P1 normal
Assignee: acpi_config-hotplug
URL: bjorn.helgaas
Keywords:
Depends on:
Blocks:
 
Reported: 2010-02-22 12:16 UTC by Andi Kleen
Modified: 2010-04-04 00:29 UTC (History)
3 users (show)

See Also:
Kernel Version: 2.6.32
Subsystem:
Regression: No
Bisected commit-id:


Attachments

Description Andi Kleen 2010-02-22 12:16:37 UTC
I noticed that a lot of the modalias entries generated for ACPI devices
are useless.

"acpi:device:" doesn't really help anything. 

Fill in something useful?


./LNXSYSTM:00/LNXSYBUS:00/PNP0C0E:00/modalias:acpi:PNP0C0E:
./LNXSYSTM:00/LNXSYBUS:00/PNP0A08:00/modalias:acpi:PNP0A08:PNP0A03:
./LNXSYSTM:00/LNXSYBUS:00/PNP0A08:00/device:00/modalias:acpi:device:
./LNXSYSTM:00/LNXSYBUS:00/PNP0A08:00/device:01/modalias:acpi:device:
./LNXSYSTM:00/LNXSYBUS:00/PNP0A08:00/device:02/modalias:acpi:device:
./LNXSYSTM:00/LNXSYBUS:00/PNP0A08:00/device:03/modalias:acpi:device:
./LNXSYSTM:00/LNXSYBUS:00/PNP0A08:00/device:04/modalias:acpi:device:
./LNXSYSTM:00/LNXSYBUS:00/PNP0A08:00/device:05/modalias:acpi:device:
./LNXSYSTM:00/LNXSYBUS:00/PNP0A08:00/device:06/modalias:acpi:device:
./LNXSYSTM:00/LNXSYBUS:00/PNP0A08:00/device:07/modalias:acpi:device:
Comment 1 Zhang Rui 2010-03-02 08:22:34 UTC
These names (PNPxxxx) are defined in the ACPI scan code, by invoking the _HID method of the ACPI device. And this PNP id is used to bind to ACPI drivers.

But unfortunately, not all the ACPI devices have such a method.

And some drivers, especially the platform drivers, use certain device/method name as an indicator to bind the ACPI devices, which is not stated in the ACPI spec, and beyond the ACPI core code's scope.

For the devices left, "acpi:device" just mean that there is no ACPI driver associated with any of these devices.

I don't think there is anything useful can be filled here for these devices. :)

Andi, please re-open it if you still have any questions.

Note You need to log in before you can comment on or make changes to this bug.