[PATCH 3.18 24/90] usb: chipidea: Prevent unbalanced IRQ disable

[Greg Kroah-Hartman]

3.18-stable review patch.  If anyone has any objections, please let me know.

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

From: Loic Poulain <loic.poulain@xxxxxxxxxx>

[ Upstream commit 8b97d73c4d72a2abf58f8e49062a7ee1e5f1334e ]

The ChipIdea IRQ is disabled before scheduling the otg work and
re-enabled on otg work completion. However if the job is already
scheduled we have to undo the effect of disable_irq int order to
balance the IRQ disable-depth value.

Fixes: be6b0c1bd0be ("usb: chipidea: using one inline function to cover queue work operations")
Signed-off-by: Loic Poulain <loic.poulain@xxxxxxxxxx>
Signed-off-by: Peter Chen <peter.chen@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/usb/chipidea/otg.h |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/usb/chipidea/otg.h
+++ b/drivers/usb/chipidea/otg.h
@@ -20,7 +20,8 @@ void ci_handle_vbus_change(struct ci_hdr
 static inline void ci_otg_queue_work(struct ci_hdrc *ci)
 {
 	disable_irq_nosync(ci->irq);
-	queue_work(ci->wq, &ci->work);
+	if (queue_work(ci->wq, &ci->work) == false)
+		enable_irq(ci->irq);
 }
 
 #endif /* __DRIVERS_USB_CHIPIDEA_OTG_H */