Arguments

Description

WARNING - don't use this routine to reset a composite device (one with multiple interfaces owned by separate drivers)! Use usb_reset_composite_device instead.

Do a port reset, reassign the device's address, and establish its former operating configuration. If the reset fails, or the device's descriptors change from their values before the reset, or the original configuration and altsettings cannot be restored, a flag will be set telling khubd to pretend the device has been disconnected and then re-connected. All drivers will be unbound, and the device will be re-enumerated and probed all over again.

Returns 0 if the reset succeeded, -ENODEV if the device has been flagged for logical disconnection, or some other negative error code if the reset wasn't even attempted.

The caller must own the device lock. For example, it's safe to use this from a driver probe routine after downloading new firmware. For calls that might not occur during probe, drivers should lock the device using usb_lock_device_for_reset.

Locking exception

This routine may also be called from within an autoresume handler. Such usage won't conflict with other tasks holding the device lock because these tasks should always call usb_autopm_resume_device, thereby preventing any unwanted autoresume.