[PATCH 3.16 065/212] usb: dwc3: gadget: skip Set/Clear Halt when invalid

[Ben Hutchings]

3.16.44-rc1 review patch.  If anyone has any objections, please let me know.

------------------

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

commit ffb80fc672c3a7b6afd0cefcb1524fb99917b2f3 upstream.

At least macOS seems to be sending
ClearFeature(ENDPOINT_HALT) to endpoints which
aren't Halted. This makes DWC3's CLEARSTALL command
time out which causes several issues for the driver.

Instead, let's just return 0 and bail out early.

Signed-off-by: Felipe Balbi <felipe.ba...@linux.intel.com>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <b...@decadent.org.uk>
---
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -1346,6 +1346,9 @@ int __dwc3_gadget_ep_set_halt(struct dwc
        memset(&params, 0x00, sizeof(params));
 
        if (value) {
+               if (dep->flags & DWC3_EP_STALL)
+                       return 0;
+
                if (!protocol && ((dep->direction && dep->flags & DWC3_EP_BUSY) 
||
                                (!list_empty(&dep->req_queued) ||
                                 !list_empty(&dep->request_list)))) {
@@ -1362,6 +1365,9 @@ int __dwc3_gadget_ep_set_halt(struct dwc
                else
                        dep->flags |= DWC3_EP_STALL;
        } else {
+               if (!(dep->flags & DWC3_EP_STALL))
+                       return 0;
+
                ret = dwc3_send_gadget_ep_cmd(dwc, dep->number,
                        DWC3_DEPCMD_CLEARSTALL, &params);
                if (ret)