[PATCH 12/70] USB: UHCI: fix for suspend of virtual HP controller

From: Luis Henriques
Date: Tue Jun 04 2013 - 10:25:51 EST -stable 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: Luis Henriques <luis.henriques@xxxxxxxxxxxxx>
drivers/usb/host/uhci-hub.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/host/uhci-hub.c b/drivers/usb/host/uhci-hub.c
index 768d542..c994655 100644
--- a/drivers/usb/host/uhci-hub.c
+++ b/drivers/usb/host/uhci-hub.c
@@ -222,7 +222,8 @@ static int uhci_hub_status_data(struct usb_hcd *hcd, char *buf)
/* 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);


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