usb: chipidea: udc: don't touch DP when controller is in host mode

When the controller is configured to be dual role and it's in host mode,
if bind udc and gadgt driver, those gadget operations will do gadget
disconnect and finally pull down DP line, which will break host function.

Cc: <stable@vger.kernel.org> # 4.1+
Signed-off-by: Li Jun <jun.li@nxp.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>

diff --git a/drivers/usb/chipidea/udc.c b/drivers/usb/chipidea/udc.c
index 065f5d97aa6708ebb3239d7778bb185d19412e5b..dfec5a176315c8545d951f88d56cc18d7f4fda45 100644 (file)
--- a/drivers/usb/chipidea/udc.c
+++ b/drivers/usb/chipidea/udc.c
@@ -1596,8 +1596,11 @@ static int ci_udc_pullup(struct usb_gadget *_gadget, int is_on)
 {
        struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
 
-       /* Data+ pullup controlled by OTG state machine in OTG fsm mode */
-       if (ci_otg_is_fsm_mode(ci))
+       /*
+        * Data+ pullup controlled by OTG state machine in OTG fsm mode;
+        * and don't touch Data+ in host mode for dual role config.
+        */
+       if (ci_otg_is_fsm_mode(ci) || ci->role == CI_ROLE_HOST)
                return 0;
 
        pm_runtime_get_sync(&ci->gadget.dev);