diff options
| author | Janusz Dziedzic <januszx.dziedzic@intel.com> | 2017-03-13 13:11:32 +0100 |
|---|---|---|
| committer | Felipe Balbi <felipe.balbi@linux.intel.com> | 2017-03-22 10:20:36 +0100 |
| commit | de288e36fe33f7e06fa272bc8e2f85aa386d99aa (patch) | |
| tree | 852db978a33b3518b4e4a74b977fc75da3ead2a6 /drivers | |
| parent | Linux 4.11-rc3 (diff) | |
| download | linux-de288e36fe33f7e06fa272bc8e2f85aa386d99aa.tar.xz linux-de288e36fe33f7e06fa272bc8e2f85aa386d99aa.zip | |
usb: dwc3: gadget: delay unmap of bounced requests
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>
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 0d75158e43fe..79e7a3480d51 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -171,6 +171,7 @@ 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; req->started = false; list_del(&req->list); @@ -180,11 +181,19 @@ 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_by_dev(dwc->sysdev, - &req->request, req->direction); + unmap_after_complete = true; + } else { + usb_gadget_unmap_request_by_dev(dwc->sysdev, + &req->request, req->direction); + } trace_dwc3_gadget_giveback(req); @@ -192,6 +201,10 @@ void dwc3_gadget_giveback(struct dwc3_ep *dep, struct dwc3_request *req, usb_gadget_giveback_request(&dep->endpoint, &req->request); spin_lock(&dwc->lock); + if (unmap_after_complete) + usb_gadget_unmap_request_by_dev(dwc->sysdev, + &req->request, req->direction); + if (dep->number > 1) pm_runtime_put(dwc->dev); } |