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From ad3f6b5b188c572bd07cc5929e844138c2d95915 Mon Sep 17 00:00:00 2001
From: Gerd Hoffmann <kraxel@redhat.com>
Date: Fri, 13 Nov 2015 13:32:34 +0100
Subject: [PATCH 1/6] ehci: clear suspend bit on detach

Message-id: <1447421554-28366-2-git-send-email-kraxel@redhat.com>
Patchwork-id: 68349
O-Subject: [RHEL-7.3 qemu-kvm PATCH 1/1] ehci: clear suspend bit on detach
Bugzilla: 1268879
RH-Acked-by: Markus Armbruster <armbru@redhat.com>
RH-Acked-by: John Snow <jsnow@redhat.com>
RH-Acked-by: Laszlo Ersek <lersek@redhat.com>

When a device is detached, clear the suspend bit (PORTSC_SUSPEND)
in the port status register.

The specs are not *that* clear what is supposed to happen in case
a suspended device is unplugged.  But the enable bit (PORTSC_PED)
is cleared, and the specs mention setting suspend with enable being
unset is undefined behavior.  So clearing them both looks reasonable,
and it actually fixes the reported bug.

Cc: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Message-id: 1445413462-18004-1-git-send-email-kraxel@redhat.com
(cherry picked from commit cbf82fa01e6fd4ecb234b235b10ffce548154a95)
Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
---
 hw/usb/hcd-ehci.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/hw/usb/hcd-ehci.c b/hw/usb/hcd-ehci.c
index 02d2ab7..3429c77 100644
--- a/hw/usb/hcd-ehci.c
+++ b/hw/usb/hcd-ehci.c
@@ -802,7 +802,7 @@ static void ehci_detach(USBPort *port)
     ehci_queues_rip_device(s, port->dev, 0);
     ehci_queues_rip_device(s, port->dev, 1);
 
-    *portsc &= ~(PORTSC_CONNECT|PORTSC_PED);
+    *portsc &= ~(PORTSC_CONNECT|PORTSC_PED|PORTSC_SUSPEND);
     *portsc |= PORTSC_CSC;
 
     ehci_raise_irq(s, USBSTS_PCD);
-- 
1.8.3.1