[PATCH 3.10 106/319] usb: dwc3: gadget: increment request->actual once

Willy Tarreau
2017-02-05T19:28:35Z

From: Felipe Balbi <felipe.balbi@linux.intel.com>

commit c7de573471832dff7d31f0c13b0f143d6f017799 upstream.

When using SG lists, we would end up setting
request->actual to:

num_mapped_sgs * (request->length - count)

Let's fix that up by incrementing request->actual
only once.

Reported-by: Brian E Rogers <brian.e.rogers@intel.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
---
drivers/usb/dwc3/gadget.c | 19 +++++++++++--------
1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 6e70c88..0dfee61 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -1802,14 +1802,6 @@ static int __dwc3_cleanup_done_trbs(struct dwc3 *dwc, struct dwc3_ep *dep,
s_pkt = 1;
}

- /*
- * We assume here we will always receive the entire data block
- * which we should receive. Meaning, if we program RX to
- * receive 4K but we receive only 2K, we assume that's all we
- * should receive and we simply bounce the request back to the
- * gadget driver for further processing.
- */
- req->request.actual += req->request.length - count;
if (s_pkt)
return 1;
if ((event->status & DEPEVT_STATUS_LST) &&
@@ -1829,6 +1821,7 @@ static int dwc3_cleanup_done_reqs(struct dwc3 *dwc, struct dwc3_ep *dep,
struct dwc3_trb *trb;
unsigned int slot;
unsigned int i;
+ int count = 0;
int ret;

do {
@@ -1845,6 +1838,8 @@ static int dwc3_cleanup_done_reqs(struct dwc3 *dwc, struct dwc3_ep *dep,
slot++;
slot %= DWC3_TRB_NUM;
trb = &dep->trb_pool[slot];
+ count += trb->size & DWC3_TRB_SIZE_MASK;
+

ret = __dwc3_cleanup_done_trbs(dwc, dep, req, trb,
event, status);
@@ -1852,6 +1847,14 @@ static int dwc3_cleanup_done_reqs(struct dwc3 *dwc, struct dwc3_ep *dep,
break;
}while (++i < req->request.num_mapped_sgs);

+ /*
+ * We assume here we will always receive the entire data block
+ * which we should receive. Meaning, if we program RX to
+ * receive 4K but we receive only 2K, we assume that's all we
+ * should receive and we simply bounce the request back to the
+ * gadget driver for further processing.
+ */
+ req->request.actual += req->request.length - count;
dwc3_gadget_giveback(dep, req, status);

if (ret)
--
2.8.0.rc2.1.gbe9624a