We need udelay(100) after every END TRANSFER, so it is better to keep it
within dwc3_stop_active_transfer.
Signed-off-by: Pratyush Anand <pratyush.anand@xxxxxx>
---
drivers/usb/dwc3/gadget.c | 42 +++++++++++++++++++++---------------------
1 files changed, 21 insertions(+), 21 deletions(-)
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index cc8834c..9699723 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -566,27 +566,6 @@ static void dwc3_remove_requests(struct dwc3 *dwc, struct dwc3_ep *dep)
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);
-
while (!list_empty(&dep->req_queued)) {
req = next_request(&dep->req_queued);
@@ -1927,6 +1906,27 @@ static void dwc3_stop_active_transfer(struct dwc3 *dwc, u32 epnum)
ret = dwc3_send_gadget_ep_cmd(dwc, dep->number, cmd, ¶ms);
WARN_ON_ONCE(ret);
dep->resource_index = 0;
+
+ /*
+ * 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);
}
static void dwc3_stop_active_transfers(struct dwc3 *dwc)
--
1.7.5.4
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