xHCI: keep track of ports being resumed and indicate in hub_status_data
This commit adds a bit-array to xhci bus_state for keeping track of
which ports are undergoing a resume transition. If any of the bits
are set when xhci_hub_status_data() is called, the routine will return
a non-zero value even if no ports have any status changes pending.
This will allow usbcore to handle races between root-hub suspend and
port wakeup.
This patch should be backported to kernels as old as 3.4, that contain
the commit 879d38e6bc36d73b0ac40ec9b0d839fda9fa8b1a "USB: fix race
between root-hub suspend and remote wakeup".
Signed-off-by: Andiry Xu <andiry.xu@amd.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: stable@vger.kernel.org
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index 3d69c4b..ce1edd7 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1362,6 +1362,8 @@
u32 suspended_ports;
u32 port_remote_wakeup;
unsigned long resume_done[USB_MAXCHILDREN];
+ /* which ports have started to resume */
+ unsigned long resuming_ports;
};
static inline unsigned int hcd_index(struct usb_hcd *hcd)