usb: dwc3: gadget: fix set_halt() bug with pending transfers

[ Upstream commit 7a60855972f0d3c014093046cb6f013a1ee5bb19 ]

According to our Gadget Framework API documentation,
->set_halt() *must* return -EAGAIN if we have pending
transfers (on either direction) or FIFO isn't empty (on
TX endpoints).

Fix this bug so that the mass storage gadget can be used
without stall=0 parameter.

This patch should be backported to all kernels since v3.2.

Suggested-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c
index 21a3520..0985ff7 100644 (file)
--- a/drivers/usb/dwc3/ep0.c
+++ b/drivers/usb/dwc3/ep0.c
@@ -251,7 +251,7 @@ static void dwc3_ep0_stall_and_restart(struct dwc3 *dwc)
 
        /* stall is always issued on EP0 */
        dep = dwc->eps[0];
-       __dwc3_gadget_ep_set_halt(dep, 1);
+       __dwc3_gadget_ep_set_halt(dep, 1, false);
        dep->flags = DWC3_EP_ENABLED;
        dwc->delayed_status = false;
 
@@ -461,7 +461,7 @@ static int dwc3_ep0_handle_feature(struct dwc3 *dwc,
                                return -EINVAL;
                        if (set == 0 && (dep->flags & DWC3_EP_WEDGE))
                                break;
-                       ret = __dwc3_gadget_ep_set_halt(dep, set);
+                       ret = __dwc3_gadget_ep_set_halt(dep, set, true);
                        if (ret)
                                return -EINVAL;
                        break;

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index bdff527..d90c70c 100644 (file)
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -587,7 +587,7 @@ static int __dwc3_gadget_ep_disable(struct dwc3_ep *dep)
 
        /* make sure HW endpoint isn't stalled */
        if (dep->flags & DWC3_EP_STALL)
-               __dwc3_gadget_ep_set_halt(dep, 0);
+               __dwc3_gadget_ep_set_halt(dep, 0, false);
 
        reg = dwc3_readl(dwc->regs, DWC3_DALEPENA);
        reg &= ~DWC3_DALEPENA_EP(dep->number);
@@ -1185,7 +1185,7 @@ out0:
        return ret;
 }
 
-int __dwc3_gadget_ep_set_halt(struct dwc3_ep *dep, int value)
+int __dwc3_gadget_ep_set_halt(struct dwc3_ep *dep, int value, int protocol)
 {
        struct dwc3_gadget_ep_cmd_params        params;
        struct dwc3                             *dwc = dep->dwc;
@@ -1194,6 +1194,14 @@ int __dwc3_gadget_ep_set_halt(struct dwc3_ep *dep, int value)
        memset(&params, 0x00, sizeof(params));
 
        if (value) {
+               if (!protocol && ((dep->direction && dep->flags & DWC3_EP_BUSY) ||
+                               (!list_empty(&dep->req_queued) ||
+                                !list_empty(&dep->request_list)))) {
+                       dev_dbg(dwc->dev, "%s: pending request, cannot halt\n",
+                                       dep->name);
+                       return -EAGAIN;
+               }
+
                ret = dwc3_send_gadget_ep_cmd(dwc, dep->number,
                        DWC3_DEPCMD_SETSTALL, &params);
                if (ret)
@@ -1233,7 +1241,7 @@ static int dwc3_gadget_ep_set_halt(struct usb_ep *ep, int value)
                goto out;
        }
 
-       ret = __dwc3_gadget_ep_set_halt(dep, value);
+       ret = __dwc3_gadget_ep_set_halt(dep, value, false);
 out:
        spin_unlock_irqrestore(&dwc->lock, flags);
 
@@ -1253,7 +1261,7 @@ static int dwc3_gadget_ep_set_wedge(struct usb_ep *ep)
        if (dep->number == 0 || dep->number == 1)
                return dwc3_gadget_ep0_set_halt(ep, 1);
        else
-               return dwc3_gadget_ep_set_halt(ep, 1);
+               return __dwc3_gadget_ep_set_halt(dep, 1, false);
 }
 
 /* -------------------------------------------------------------------------- */

diff --git a/drivers/usb/dwc3/gadget.h b/drivers/usb/dwc3/gadget.h
index a0ee75b..ac62558 100644 (file)
--- a/drivers/usb/dwc3/gadget.h
+++ b/drivers/usb/dwc3/gadget.h
@@ -85,7 +85,7 @@ void dwc3_ep0_out_start(struct dwc3 *dwc);
 int dwc3_gadget_ep0_set_halt(struct usb_ep *ep, int value);
 int dwc3_gadget_ep0_queue(struct usb_ep *ep, struct usb_request *request,
                gfp_t gfp_flags);
-int __dwc3_gadget_ep_set_halt(struct dwc3_ep *dep, int value);
+int __dwc3_gadget_ep_set_halt(struct dwc3_ep *dep, int value, int protocol);
 
 /**
  * dwc3_gadget_ep_get_transfer_index - Gets transfer index from HW