Bluetooth: hidp: fix device disconnect on idle timeout
commit 660f0fc0 upstream. The HIDP specs define an idle-timeout which automatically disconnects a device. This has always been implemented in the HIDP layer and forced a synchronous shutdown of the hidp-scheduler. This works just fine, but lacks a forced disconnect on the underlying l2cap channels. This has been broken since: commit 5205185d Author: David Herrmann <dh.herrmann@gmail.com> Date: Sat Apr 6 20:28:47 2013 +0200 Bluetooth: hidp: remove old session-management The old session-management always forced an l2cap error on the ctrl/intr channels when shutting down. The new session-management skips this, as we don't want to enforce channel policy on the caller. In other words, if user-space removes an HIDP device, the underlying channels (which are *owned* and *referenced* by user-space) are still left active. User-space needs to call shutdown(2) or close(2) to release them. Unfortunately, this does not work with idle-timeouts. There is no way to signal user-space that the HIDP layer has been stopped. The API simply does not support any event-passing except for poll(2). Hence, we restore old behavior and force EUNATCH on the sockets if the HIDP layer is disconnected due to idle-timeouts (behavior of explicit disconnects remains unmodified). User-space can still call getsockopt(..., SO_ERROR, ...) ..to retrieve the EUNATCH error and clear sk_err. Hence, the channels can still be re-used (which nobody does so far, though). Therefore, the API still supports the new behavior, but with this patch it's also compatible to the old implicit channel shutdown. Reported-by: Mark Haun <haunma@keteu.org> Reported-by: Luiz Augusto von Dentz <luiz.dentz@gmail.com> Signed-off-by: David Herrmann <dh.herrmann@gmail.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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