From d8521afe35862f4fbe3ccd6ca37897c0a304edf3 Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Tue, 20 May 2014 18:08:28 -0700 Subject: usb: assign default peer ports for root hubs Assume that the peer of a superspeed port is the port with the same id on the shared_hcd root hub. This identification scheme is required of external hubs by the USB3 spec [1]. However, for root hubs, tier mismatch may be in effect [2]. Tier mismatch can only be enumerated via platform firmware. For now, simply perform the nominal association. A new lock 'usb_port_peer_mutex' is introduced to synchronize port device add/remove with peer lookups. It protects peering against changes to hcd->shared_hcd, hcd->self.root_hub, hdev->maxchild, and port_dev->child pointers. [1]: usb 3.1 section 10.3.3 [2]: xhci 1.1 appendix D Cc: Alan Stern [alan: usb_port_peer_mutex locking scheme] Acked-by: Alan Stern Signed-off-by: Dan Williams Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/hub.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'drivers/usb/core/hub.h') diff --git a/drivers/usb/core/hub.h b/drivers/usb/core/hub.h index 4bd72dd303d5..fcad5f9d12f0 100644 --- a/drivers/usb/core/hub.h +++ b/drivers/usb/core/hub.h @@ -82,6 +82,7 @@ struct usb_hub { * @child: usb device attached to the port * @dev: generic device interface * @port_owner: port's owner + * @peer: related usb2 and usb3 ports (share the same connector) * @connect_type: port's connect type * @portnum: port index num based one * @power_is_on: port's power state @@ -91,6 +92,7 @@ struct usb_port { struct usb_device *child; struct device dev; struct usb_dev_state *port_owner; + struct usb_port *peer; enum usb_port_connect_type connect_type; u8 portnum; unsigned power_is_on:1; -- cgit