USB: musb: gadget_ep0: avoid SetupEnd interrupt

Gadget stalling a zero-length SETUP request results in this error message:

SetupEnd came in a wrong ep0stage idle

In order to avoid it, always set the CSR0.DataEnd bit after detecting a zero-
length request.  Add the missing '\n' to the error message itself as well...

Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Acked-by: Anand Gadiyar <gadiyar@ti.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Felipe Balbi <felipe.balbi@nokia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/musb/musb_gadget_ep0.c b/drivers/usb/musb/musb_gadget_ep0.c
index 8fba3f1..53d0645 100644 (file)
--- a/drivers/usb/musb/musb_gadget_ep0.c
+++ b/drivers/usb/musb/musb_gadget_ep0.c
@@ -664,7 +664,7 @@ irqreturn_t musb_g_ep0_irq(struct musb *musb)
                        musb->ep0_state = MUSB_EP0_STAGE_STATUSIN;
                        break;
                default:
-                       ERR("SetupEnd came in a wrong ep0stage %s",
+                       ERR("SetupEnd came in a wrong ep0stage %s\n",
                            decode_ep0stage(musb->ep0_state));
                }
                csr = musb_readw(regs, MUSB_CSR0);
@@ -787,12 +787,18 @@ setup:
                                handled = service_zero_data_request(
                                                musb, &setup);
 
+                               /*
+                                * We're expecting no data in any case, so
+                                * always set the DATAEND bit -- doing this
+                                * here helps avoid SetupEnd interrupt coming
+                                * in the idle stage when we're stalling...
+                                */
+                               musb->ackpend |= MUSB_CSR0_P_DATAEND;
+
                                /* status stage might be immediate */
-                               if (handled > 0) {
-                                       musb->ackpend |= MUSB_CSR0_P_DATAEND;
+                               if (handled > 0)
                                        musb->ep0_state =
                                                MUSB_EP0_STAGE_STATUSIN;
-                               }
                                break;
 
                        /* sequence #1 (IN to host), includes GET_STATUS