1 files changed, 29 insertions, 14 deletions

diff --git a/drivers/usb/musb/musb_host.c b/drivers/usb/musb/musb_host.c
index ff095956ca96..521fd83f5b9d 100644
--- a/drivers/usb/musb/musb_host.c
+++ b/drivers/usb/musb/musb_host.c
@@ -125,6 +125,29 @@ static void musb_h_tx_flush_fifo(struct musb_hw_ep *ep)
         }
 }
 
+static void musb_h_ep0_flush_fifo(struct musb_hw_ep *ep)
+{
+        void __iomem    *epio = ep->regs;
+        u16             csr;
+        int             retries = 5;
+
+        /* scrub any data left in the fifo */
+        do {
+                csr = musb_readw(epio, MUSB_TXCSR);
+                if (!(csr & (MUSB_CSR0_TXPKTRDY | MUSB_CSR0_RXPKTRDY)))
+                        break;
+                musb_writew(epio, MUSB_TXCSR, MUSB_CSR0_FLUSHFIFO);
+                csr = musb_readw(epio, MUSB_TXCSR);
+                udelay(10);
+        } while (--retries);
+
+        WARN(!retries, "Could not flush host TX%d fifo: csr: %04x\n",
+                        ep->epnum, csr);
+
+        /* and reset for the next transfer */
+        musb_writew(epio, MUSB_TXCSR, 0);
+}
+
 /*
  * Start transmit. Caller is responsible for locking shared resources.
  * musb must be locked.
@@ -694,10 +717,7 @@ static void musb_ep_program(struct musb *musb, u8 epnum,
                         csr = musb_readw(epio, MUSB_TXCSR);
                 } else {
                         /* endpoint 0: just flush */
-                        musb_writew(epio, MUSB_CSR0,
-                                csr | MUSB_CSR0_FLUSHFIFO);
-                        musb_writew(epio, MUSB_CSR0,
-                                csr | MUSB_CSR0_FLUSHFIFO);
+                        musb_h_ep0_flush_fifo(hw_ep);
                 }
 
                 /* target addr and (for multipoint) hub addr/port */
@@ -1063,11 +1083,7 @@ irqreturn_t musb_h_ep0_irq(struct musb *musb)
                         csr &= ~MUSB_CSR0_H_NAKTIMEOUT;
                         musb_writew(epio, MUSB_CSR0, csr);
                 } else {
-                        csr |= MUSB_CSR0_FLUSHFIFO;
-                        musb_writew(epio, MUSB_CSR0, csr);
-                        musb_writew(epio, MUSB_CSR0, csr);
-                        csr &= ~MUSB_CSR0_H_NAKTIMEOUT;
-                        musb_writew(epio, MUSB_CSR0, csr);
+                        musb_h_ep0_flush_fifo(hw_ep);
                 }
 
                 musb_writeb(epio, MUSB_NAKLIMIT0, 0);
@@ -1081,10 +1097,7 @@ irqreturn_t musb_h_ep0_irq(struct musb *musb)
                  * SHOULD NEVER HAPPEN! */
                 ERR("no URB for end 0\n");
 
-                musb_writew(epio, MUSB_CSR0, MUSB_CSR0_FLUSHFIFO);
-                musb_writew(epio, MUSB_CSR0, MUSB_CSR0_FLUSHFIFO);
-                musb_writew(epio, MUSB_CSR0, 0);
-
+                musb_h_ep0_flush_fifo(hw_ep);
                 goto done;
         }
 
@@ -2043,7 +2056,7 @@ static int musb_cleanup_urb(struct urb *urb, struct musb_qh *qh, int is_in)
                  * endpoint's irq status here to avoid bogus irqs.
                  * clearing that status is platform-specific...
                  */
-        } else {
+        } else if (ep->epnum) {
                 musb_h_tx_flush_fifo(ep);
                 csr = musb_readw(epio, MUSB_TXCSR);
                 csr &= ~(MUSB_TXCSR_AUTOSET
@@ -2057,6 +2070,8 @@ static int musb_cleanup_urb(struct urb *urb, struct musb_qh *qh, int is_in)
                 musb_writew(epio, MUSB_TXCSR, csr);
                 /* flush cpu writebuffer */
                 csr = musb_readw(epio, MUSB_TXCSR);
+        } else  {
+                musb_h_ep0_flush_fifo(ep);
         }
         if (status == 0)
                 musb_advance_schedule(ep->musb, urb, ep, is_in);