On Fri, Feb 28, 2025 at 07:50:25AM +0000, Pawel Laszczak wrote:
The xHC resources allocated for USB devices are not released in correct order after resuming in case when while suspend device was reconnected.
This issue has been detected during the fallowing scenario:
- connect hub HS to root port
- connect LS/FS device to hub port
- wait for enumeration to finish
- force host to suspend
- reconnect hub attached to root port
- wake host
For this scenario during enumeration of USB LS/FS device the Cadence xHC reports completion error code for xHC commands because the xHC resources used for devices has not been properly released. XHCI specification doesn't mention that device can be reset in any order so, we should not treat this issue as Cadence xHC controller bug. Similar as during disconnecting in this case the device resources should be cleared starting form the last usb device in tree toward the root hub. To fix this issue usbcore driver should call hcd->driver->reset_device for all USB devices connected to hub which was reconnected while suspending.
Fixes: 3d82904559f4 ("usb: cdnsp: cdns3 Add main part of Cadence USBSSP DRD Driver") cc: stable@vger.kernel.org Signed-off-by: Pawel Laszczak pawell@cadence.com
Changelog: v3:
- Changed patch title
- Corrected typo
- Moved hub_hc_release_resources above mutex_lock(hcd->address0_mutex)
v2:
- Replaced disconnection procedure with releasing only the xHC resources
Reviewed-by: Alan Stern stern@rowland.harvard.edu