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This is a rewrite of the HIDP session management. It implements HIDP as an l2cap_user sub-module so we get proper notification when the underlying connection goes away. The helpers are not yet used but only added in this commit. The old session management is still used and will be removed in a following patch. The old session-management was flawed. Hotplugging is horribly broken and we have no way of getting notified when the underlying connection goes down. The whole idea of removing the HID/input sub-devices from within the session itself is broken and suffers from major dead-locks. We never can guarantee that the session can unregister itself as long as we use synchronous shutdowns. This can only work with asynchronous shutdowns. However, in this case we _must_ be able to unregister the session from the outside as otherwise the l2cap_conn object might be unlinked before we are. The new session-management is based on l2cap_user. There is only one way how to add a session and how to delete a session: "probe" and "remove" callbacks from l2cap_user. This guarantees that the session can be registered and unregistered at _any_ time without any synchronous shutdown. On the other hand, much work has been put into proper session-refcounting. We can unregister/unlink the session only if we can guarantee that it will stay alive. But for asynchronous shutdowns we never know when the last user goes away so we must use proper ref-counting. The old ->conn field has been renamed to ->hconn so we can reuse ->conn in the new session management. No other existing HIDP code is modified. Signed-off-by: David Herrmann <dh.herrmann@gmail.com> Acked-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk> |
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.. | ||
core.c | ||
hidp.h | ||
Kconfig | ||
Makefile | ||
sock.c |