[PATCH 1/1] USB: EHCI: wait 4ms until the device enters full-speed idle

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If the high-speed device does not enter full-speed idle after
wakeup on disconnect logic has effected, there will be an
unexpected disconnect wakeup interrupt due to the bus is still SE0.

Signed-off-by: Peter Chen <peter.chen@xxxxxxxxxxxxx>
---
 drivers/usb/host/ehci-hub.c |    9 +++++++++
 1 files changed, 9 insertions(+), 0 deletions(-)

diff --git a/drivers/usb/host/ehci-hub.c b/drivers/usb/host/ehci-hub.c
index 47b858f..d14827d 100644
--- a/drivers/usb/host/ehci-hub.c
+++ b/drivers/usb/host/ehci-hub.c
@@ -301,6 +301,15 @@ static int ehci_bus_suspend (struct usb_hcd *hcd)
 
 		if (t1 != t2) {
 			ehci_writel(ehci, t2, reg);
+			if ((t2 & PORT_WKDISC_E)
+				&& (ehci_port_speed(ehci, t2) ==
+					USB_PORT_STAT_HIGH_SPEED))
+				/*
+				 * If the high-speed device has not switched
+				 * to full-speed idle before WKDISC_E has
+				 * effected, there will be a WKDISC event.
+				 */
+				mdelay(4);
 			changed = 1;
 		}
 	}
-- 
1.7.8


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