From 7ababa926c66c5c5a862489b475ff5d96a7dd03a Mon Sep 17 00:00:00 2001 From: Gregory Herrero Date: Wed, 29 Apr 2015 22:09:08 +0200 Subject: [PATCH] usb: dwc2: gadget: prevent new request submission during suspend If usb controller is in partial power down, any write to registers may cause unpredictable behavior. Thus, prevent any new request submission once controller is in partial power down. Acked-by: John Youn Signed-off-by: Gregory Herrero Signed-off-by: Felipe Balbi --- drivers/usb/dwc2/gadget.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c index a360f49d3fd0..732761f9466b 100644 --- a/drivers/usb/dwc2/gadget.c +++ b/drivers/usb/dwc2/gadget.c @@ -790,6 +790,13 @@ static int s3c_hsotg_ep_queue(struct usb_ep *ep, struct usb_request *req, ep->name, req, req->length, req->buf, req->no_interrupt, req->zero, req->short_not_ok); + /* Prevent new request submission when controller is suspended */ + if (hs->lx_state == DWC2_L2) { + dev_dbg(hs->dev, "%s: don't submit request while suspended\n", + __func__); + return -EAGAIN; + } + /* initialise status of the request */ INIT_LIST_HEAD(&hs_req->queue); req->actual = 0;