[RESEND PATCH v3 1/2] usb: dwc3: gadget: Add disconnect checking when changing function dynamically

[Baolin Wang]

When system has stpped the gadget, we should avoid queuing any requests
which will cause tranfer failed. Thus adding some disconnect checking to
avoid this situation.

Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxx>
---
Changes since v2:
 - Move disconnect checking into dwc3_send_gadget_ep_cmd().
 - Rename completion name and issue complete() at one place.
 - Move completion initialization into dwc3_gadget_init().

Changes since v1:
 - Split into 2 separate ptaches.
 - Choose complete mechanism instead of polling.
---
 drivers/usb/dwc3/gadget.c |    3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 1783406..ca2ae5b 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -241,6 +241,9 @@ int dwc3_send_gadget_ep_cmd(struct dwc3_ep *dep, unsigned cmd,
 	int			susphy = false;
 	int			ret = -EINVAL;
 
+	if (!dwc->pullups_connected)
+		return -ESHUTDOWN;
+
 	/*
 	 * Synopsys Databook 2.60a states, on section 6.3.2.5.[1-8], that if
 	 * we're issuing an endpoint command, we must check if
-- 
1.7.9.5