[PATCH 4.0 41/72] usb: chipidea: otg: remove mutex unlock and lock while stop and start role

[Greg Kroah-Hartman]

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

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

From: Li Jun <jun.li@xxxxxxxxxxxxx>

commit a5a356cee89f86ff86cc3ce24136ca1f802c1bf1 upstream.

Wrongly release mutex lock during otg_statemachine may result in re-enter
otg_statemachine, which is not allowed, we should do next state transtition
after previous one completed.

Fixes: 826cfe751f3e ("usb: chipidea: add OTG fsm operation functions implementation")
Signed-off-by: Li Jun <jun.li@xxxxxxxxxxxxx>
Signed-off-by: Peter Chen <peter.chen@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/usb/chipidea/otg_fsm.c |    4 ----
 1 file changed, 4 deletions(-)

--- a/drivers/usb/chipidea/otg_fsm.c
+++ b/drivers/usb/chipidea/otg_fsm.c
@@ -537,7 +537,6 @@ static int ci_otg_start_host(struct otg_
 {
 	struct ci_hdrc	*ci = container_of(fsm, struct ci_hdrc, fsm);
 
-	mutex_unlock(&fsm->lock);
 	if (on) {
 		ci_role_stop(ci);
 		ci_role_start(ci, CI_ROLE_HOST);
@@ -546,7 +545,6 @@ static int ci_otg_start_host(struct otg_
 		hw_device_reset(ci);
 		ci_role_start(ci, CI_ROLE_GADGET);
 	}
-	mutex_lock(&fsm->lock);
 	return 0;
 }
 
@@ -554,12 +552,10 @@ static int ci_otg_start_gadget(struct ot
 {
 	struct ci_hdrc	*ci = container_of(fsm, struct ci_hdrc, fsm);
 
-	mutex_unlock(&fsm->lock);
 	if (on)
 		usb_gadget_vbus_connect(&ci->gadget);
 	else
 		usb_gadget_vbus_disconnect(&ci->gadget);
-	mutex_lock(&fsm->lock);
 
 	return 0;
 }


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