usb: dwc3: gadget: don't wait for ep cmd IRQ
That IRQ is causing way too much trouble. We have
a different handling which was agreed with IP
provider and has been tested with FPGA and OMAP5.
Tested-by: Pratyush Anand <pratyush.anand@st.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 056ace8..0f19978 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -555,9 +555,34 @@
{
struct dwc3_request *req;
- if (!list_empty(&dep->req_queued))
+ if (!list_empty(&dep->req_queued)) {
dwc3_stop_active_transfer(dwc, dep->number);
+ /*
+ * NOTICE: We are violating what the Databook says about the
+ * EndTransfer command. Ideally we would _always_ wait for the
+ * EndTransfer Command Completion IRQ, but that's causing too
+ * much trouble synchronizing between us and gadget driver.
+ *
+ * We have discussed this with the IP Provider and it was
+ * suggested to giveback all requests here, but give HW some
+ * extra time to synchronize with the interconnect. We're using
+ * an arbitraty 100us delay for that.
+ *
+ * Note also that a similar handling was tested by Synopsys
+ * (thanks a lot Paul) and nothing bad has come out of it.
+ * In short, what we're doing is:
+ *
+ * - Issue EndTransfer WITH CMDIOC bit set
+ * - Wait 100us
+ * - giveback all requests to gadget driver
+ */
+ udelay(100);
+
+ req = next_request(&dep->req_queued);
+ dwc3_gadget_giveback(dep, req, -ESHUTDOWN);
+ }
+
while (!list_empty(&dep->request_list)) {
req = next_request(&dep->request_list);
@@ -1735,43 +1760,6 @@
}
}
-static void dwc3_process_ep_cmd_complete(struct dwc3_ep *dep,
- const struct dwc3_event_depevt *event)
-{
- struct dwc3 *dwc = dep->dwc;
- struct dwc3_event_depevt mod_ev = *event;
-
- /*
- * We were asked to remove one request. It is possible that this
- * request and a few others were started together and have the same
- * transfer index. Since we stopped the complete endpoint we don't
- * know how many requests were already completed (and not yet)
- * reported and how could be done (later). We purge them all until
- * the end of the list.
- */
- mod_ev.status = DEPEVT_STATUS_LST;
- dwc3_cleanup_done_reqs(dwc, dep, &mod_ev, -ESHUTDOWN);
- dep->flags &= ~DWC3_EP_BUSY;
- /* pending requests are ignored and are queued on XferNotReady */
-}
-
-static void dwc3_ep_cmd_compl(struct dwc3_ep *dep,
- const struct dwc3_event_depevt *event)
-{
- u32 param = event->parameters;
- u32 cmd_type = (param >> 8) & ((1 << 5) - 1);
-
- switch (cmd_type) {
- case DWC3_DEPCMD_ENDTRANSFER:
- dwc3_process_ep_cmd_complete(dep, event);
- break;
- default:
- printk(KERN_ERR "%s() unknown /unexpected type: %d\n",
- __func__, cmd_type);
- break;
- };
-}
-
static void dwc3_endpoint_interrupt(struct dwc3 *dwc,
const struct dwc3_event_depevt *event)
{
@@ -1853,7 +1841,7 @@
dev_dbg(dwc->dev, "%s FIFO Overrun\n", dep->name);
break;
case DWC3_DEPEVT_EPCMDCMPLT:
- dwc3_ep_cmd_compl(dep, event);
+ dev_vdbg(dwc->dev, "Endpoint Command Complete\n");
break;
}
}