[38/94] USB: UHCI: fix for suspend of virtual HP controller

[Ben Hutchings]

3.2.46-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>

commit 997ff893603c6455da4c5e26ba1d0f81adfecdfc upstream.

HP's virtual UHCI host controller takes a long time to suspend
(several hundred microseconds), even when no devices are attached.
This provokes a warning message from uhci-hcd in the auto-stop case.

To prevent this from happening, this patch adds a test to avoid
performing an auto-stop when the wait_for_hp quirk flag is set.  The
controller will still suspend through the normal runtime PM mechanism.
And since that pathway includes a 1-ms delay, the slowness of the
virtual hardware won't matter.

Signed-off-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
Reported-and-tested-by: ZhenHua <zhen-hual@xxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 drivers/usb/host/uhci-hub.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/usb/host/uhci-hub.c
+++ b/drivers/usb/host/uhci-hub.c
@@ -221,7 +221,8 @@ static int uhci_hub_status_data(struct u
 		/* auto-stop if nothing connected for 1 second */
 		if (any_ports_active(uhci))
 			uhci->rh_state = UHCI_RH_RUNNING;
-		else if (time_after_eq(jiffies, uhci->auto_stop_time))
+		else if (time_after_eq(jiffies, uhci->auto_stop_time) &&
+				!uhci->wait_for_hp)
 			suspend_rh(uhci, UHCI_RH_AUTO_STOPPED);
 		break;
 

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