[PATCH 3.14 186/203] usb: dwc3: gadget: fix set_halt() bug with pending transfers

From: Greg Kroah-Hartman
Date: Tue Nov 11 2014 - 20:47:45 EST


3.14-stable review patch. If anyone has any objections, please let me know.

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

From: Felipe Balbi <balbi@xxxxxx>

[ 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@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Felipe Balbi <balbi@xxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/usb/dwc3/ep0.c | 4 ++--
drivers/usb/dwc3/gadget.c | 16 ++++++++++++----
drivers/usb/dwc3/gadget.h | 2 +-
3 files changed, 15 insertions(+), 7 deletions(-)

--- a/drivers/usb/dwc3/ep0.c
+++ b/drivers/usb/dwc3/ep0.c
@@ -251,7 +251,7 @@ static void dwc3_ep0_stall_and_restart(s

/* 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(struc
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;
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -587,7 +587,7 @@ static int __dwc3_gadget_ep_disable(stru

/* 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 dwc
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(struc
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(stru
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);
}

/* -------------------------------------------------------------------------- */
--- 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


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/