[PATCH 3.19 48/75] usb: common: otg-fsm: only signal connect after switching to peripheral

[Greg Kroah-Hartman]

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

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

From: Peter Chen <peter.chen@xxxxxxxxxxxxx>

commit a886bd92267c9e3d5c912860c6fb5a68479a7643 upstream.

We should signal connect (pull up dp) after we have already
at peripheral mode, otherwise, the dp may be toggled due to
we reset controller or do disconnect during the initialization
for peripheral, then, the host may be confused during the
enumeration, eg, it finds the reset can't succeed, but the
device is still there, see below error message.

hub 1-0:1.0: USB hub found
hub 1-0:1.0: 1 port detected
hub 1-0:1.0: cannot reset port 1 (err = -32)
hub 1-0:1.0: cannot reset port 1 (err = -32)
hub 1-0:1.0: cannot reset port 1 (err = -32)
hub 1-0:1.0: cannot reset port 1 (err = -32)
hub 1-0:1.0: cannot reset port 1 (err = -32)
hub 1-0:1.0: Cannot enable port 1.  Maybe the USB cable is bad?
hub 1-0:1.0: cannot reset port 1 (err = -32)
hub 1-0:1.0: cannot reset port 1 (err = -32)
hub 1-0:1.0: cannot reset port 1 (err = -32)
hub 1-0:1.0: cannot reset port 1 (err = -32)
hub 1-0:1.0: cannot reset port 1 (err = -32)
hub 1-0:1.0: Cannot enable port 1.  Maybe the USB cable is bad?
hub 1-0:1.0: cannot reset port 1 (err = -32)
hub 1-0:1.0: cannot reset port 1 (err = -32)
hub 1-0:1.0: cannot reset port 1 (err = -32)
hub 1-0:1.0: cannot reset port 1 (err = -32)
hub 1-0:1.0: cannot reset port 1 (err = -32)
hub 1-0:1.0: Cannot enable port 1.  Maybe the USB cable is bad?
hub 1-0:1.0: cannot reset port 1 (err = -32)
hub 1-0:1.0: cannot reset port 1 (err = -32)
hub 1-0:1.0: cannot reset port 1 (err = -32)
hub 1-0:1.0: cannot reset port 1 (err = -32)
hub 1-0:1.0: cannot reset port 1 (err = -32)
hub 1-0:1.0: Cannot enable port 1.  Maybe the USB cable is bad?
hub 1-0:1.0: unable to enumerate USB device on port 1

Fixes: the issue existed when the otg fsm code was added.
Signed-off-by: Peter Chen <peter.chen@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/usb/common/usb-otg-fsm.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/usb/common/usb-otg-fsm.c
+++ b/drivers/usb/common/usb-otg-fsm.c
@@ -150,9 +150,9 @@ static int otg_set_state(struct otg_fsm
 		break;
 	case OTG_STATE_B_PERIPHERAL:
 		otg_chrg_vbus(fsm, 0);
-		otg_loc_conn(fsm, 1);
 		otg_loc_sof(fsm, 0);
 		otg_set_protocol(fsm, PROTO_GADGET);
+		otg_loc_conn(fsm, 1);
 		break;
 	case OTG_STATE_B_WAIT_ACON:
 		otg_chrg_vbus(fsm, 0);
@@ -213,10 +213,10 @@ static int otg_set_state(struct otg_fsm
 
 		break;
 	case OTG_STATE_A_PERIPHERAL:
-		otg_loc_conn(fsm, 1);
 		otg_loc_sof(fsm, 0);
 		otg_set_protocol(fsm, PROTO_GADGET);
 		otg_drv_vbus(fsm, 1);
+		otg_loc_conn(fsm, 1);
 		otg_add_timer(fsm, A_BIDL_ADIS);
 		break;
 	case OTG_STATE_A_WAIT_VFALL:


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