3.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Hemant Kumar <hemantk@xxxxxxxxxxxxxx> commit ce5bf9a50daf2d9078b505aca1cea22e88ecb94a upstream. Upon usb composition switch there is possibility of ep0 file release happening after gadget driver bind. In case of composition switch from adb to a non-adb composition gadget will never gets bound again resulting into failure of usb device enumeration. Fix this issue by checking FFS_FL_BOUND flag and avoid extra gadget driver unbind if it is already done as part of composition switch. This fixes adb reconnection error reported on Android running v4.4 and above kernel versions. Verified on Hikey running vanilla v4.15-rc7 + few out of tree Mali patches. Reviewed-at: https://android-review.googlesource.com/#/c/582632/ Cc: Felipe Balbi <balbi@xxxxxxxxxx> Cc: Greg KH <gregkh@xxxxxxxxxxxxxxxxxxxx> Cc: Michal Nazarewicz <mina86@xxxxxxxxxx> Cc: John Stultz <john.stultz@xxxxxxxxxx> Cc: Dmitry Shmidt <dimitrysh@xxxxxxxxxx> Cc: Badhri <badhri@xxxxxxxxxx> Cc: Android Kernel Team <kernel-team@xxxxxxxxxxx> Signed-off-by: Hemant Kumar <hemantk@xxxxxxxxxxxxxx> [AmitP: Cherry-picked it from android-4.14 and updated the commit log] Signed-off-by: Amit Pundir <amit.pundir@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/usb/gadget/function/f_fs.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/usb/gadget/function/f_fs.c +++ b/drivers/usb/gadget/function/f_fs.c @@ -3438,7 +3438,8 @@ static void ffs_closed(struct ffs_data * ci = opts->func_inst.group.cg_item.ci_parent->ci_parent; ffs_dev_unlock(); - unregister_gadget_item(ci); + if (test_bit(FFS_FL_BOUND, &ffs->flags)) + unregister_gadget_item(ci); return; done: ffs_dev_unlock();