USB: make HCDs responsible for managing endpoint queues
This patch (as954) implements a suggestion of David Brownell's. Now the host controller drivers are responsible for linking and unlinking URBs to/from their endpoint queues. This eliminates the possiblity of strange situations where usbcore thinks an URB is linked but the HCD thinks it isn't. It also means HCDs no longer have to check for URBs being dequeued before they were fully enqueued. In addition to the core changes, this requires changing every host controller driver and the root-hub URB handler. For the most part the required changes are fairly small; drivers have to call usb_hcd_link_urb_to_ep() in their urb_enqueue method, usb_hcd_check_unlink_urb() in their urb_dequeue method, and usb_hcd_unlink_urb_from_ep() before giving URBs back. A few HCDs make matters more complicated by the way they split up the flow of control. In addition some method interfaces get changed. The endpoint argument for urb_enqueue is now redundant so it is removed. The unlink status is required by usb_hcd_check_unlink_urb(), so it has been added to urb_dequeue. Signed-off-by: NAlan Stern <stern@rowland.harvard.edu> CC: David Brownell <david-b@pacbell.net> CC: Olav Kongas <ok@artecdesign.ee> CC: Tony Olech <tony.olech@elandigitalsystems.com> CC: Yoshihiro Shimoda <shimoda.yoshihiro@renesas.com> Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
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