diff options
author | Janusz Dziedzic <januszx.dziedzic@intel.com> | 2017-03-13 14:11:32 +0200 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-04-18 07:14:35 +0200 |
commit | 297f55bcb62ad0b6b290b01177d9395305d57020 (patch) | |
tree | 8f5f61c83283321a7f804e52d53f9437b8215fc9 /drivers | |
parent | 8cfaf0ae1f566ddfcda661bd81b625a71b16459a (diff) | |
download | linux-stable-297f55bcb62ad0b6b290b01177d9395305d57020.tar.gz linux-stable-297f55bcb62ad0b6b290b01177d9395305d57020.tar.bz2 linux-stable-297f55bcb62ad0b6b290b01177d9395305d57020.zip |
usb: dwc3: gadget: delay unmap of bounced requests
commit de288e36fe33f7e06fa272bc8e2f85aa386d99aa upstream.
In the case of bounced ep0 requests, we must delay DMA operation until
after ->complete() otherwise we might overwrite contents of req->buf.
This caused problems with RNDIS gadget.
Signed-off-by: Janusz Dziedzic <januszx.dziedzic@intel.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/usb/dwc3/gadget.c | 21 |
1 files changed, 17 insertions, 4 deletions
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index 210ff64857e1..ec7a50f98f57 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -235,6 +235,7 @@ void dwc3_gadget_giveback(struct dwc3_ep *dep, struct dwc3_request *req, int status) { struct dwc3 *dwc = dep->dwc; + unsigned int unmap_after_complete = false; int i; if (req->queued) { @@ -259,11 +260,19 @@ void dwc3_gadget_giveback(struct dwc3_ep *dep, struct dwc3_request *req, if (req->request.status == -EINPROGRESS) req->request.status = status; - if (dwc->ep0_bounced && dep->number <= 1) + /* + * NOTICE we don't want to unmap before calling ->complete() if we're + * dealing with a bounced ep0 request. If we unmap it here, we would end + * up overwritting the contents of req->buf and this could confuse the + * gadget driver. + */ + if (dwc->ep0_bounced && dep->number <= 1) { dwc->ep0_bounced = false; - - usb_gadget_unmap_request(&dwc->gadget, &req->request, - req->direction); + unmap_after_complete = true; + } else { + usb_gadget_unmap_request(&dwc->gadget, + &req->request, req->direction); + } dev_dbg(dwc->dev, "request %p from %s completed %d/%d ===> %d\n", req, dep->name, req->request.actual, @@ -273,6 +282,10 @@ void dwc3_gadget_giveback(struct dwc3_ep *dep, struct dwc3_request *req, spin_unlock(&dwc->lock); usb_gadget_giveback_request(&dep->endpoint, &req->request); spin_lock(&dwc->lock); + + if (unmap_after_complete) + usb_gadget_unmap_request(&dwc->gadget, + &req->request, req->direction); } int dwc3_send_gadget_generic_command(struct dwc3 *dwc, unsigned cmd, u32 param) |