sync libusb usb_set_configuration() + sysfs .../bConfigurationValue
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
libusb (Ubuntu) |
New
|
Undecided
|
Unassigned | ||
linux (Ubuntu) |
Incomplete
|
Undecided
|
Unassigned |
Bug Description
A USB device can offering a number of possible Configurations, with the host/operating system selecting the most suitable configuration for its needs. An example could be a media device offering either proprietary, or Mass Storage configurations.
Changing the selected configuration can be done by either:
echo 3 > /sys/devices/
or, using libusb:
usb_set_
Currently using one of these methods means that the kernel sysfs state gets out-of-sync; meaning that udev events are incorrect and the available '/dev/usbdev7.
Ideally 'libusb' should use sysfs on Linux to make the configuration change, or the kernel should make note of the raw USB commands that it passes through and update its state.
<Keybuk> the raw devices nodes are *beneath* the host
<Keybuk> they're there so you can bypass the host entirely
<Keybuk> that's kinda the difficult point
<sladen> yeah it's like raw ethernet access and complaining that you're sending ARP updates that don't match the kernel ARP table