USB: musb_gadget: remove pointless loop

Remove the pointless 'do () while (0)' loop from musb_g_tx() -- it
makes this function symmetric to musb_g_rx()...

Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/musb/musb_gadget.c b/drivers/usb/musb/musb_gadget.c
index 173c963e7f020f0d1c2e80d72efbd4c4ee385328..07d5dc97ff5e3a14494ba645407f263b87a8d6a8 100644 (file)
--- a/drivers/usb/musb/musb_gadget.c
+++ b/drivers/usb/musb/musb_gadget.c
@@ -429,112 +429,102 @@ void musb_g_tx(struct musb *musb, u8 epnum)
        DBG(4, "<== %s, txcsr %04x\n", musb_ep->end_point.name, csr);
 
        dma = is_dma_capable() ? musb_ep->dma : NULL;
-       do {
-               /* REVISIT for high bandwidth, MUSB_TXCSR_P_INCOMPTX
-                * probably rates reporting as a host error
+
+       /*
+        * REVISIT: for high bandwidth, MUSB_TXCSR_P_INCOMPTX
+        * probably rates reporting as a host error.
+        */
+       if (csr & MUSB_TXCSR_P_SENTSTALL) {
+               csr |=  MUSB_TXCSR_P_WZC_BITS;
+               csr &= ~MUSB_TXCSR_P_SENTSTALL;
+               musb_writew(epio, MUSB_TXCSR, csr);
+               return;
+       }
+
+       if (csr & MUSB_TXCSR_P_UNDERRUN) {
+               /* We NAKed, no big deal... little reason to care. */
+               csr |=   MUSB_TXCSR_P_WZC_BITS;
+               csr &= ~(MUSB_TXCSR_P_UNDERRUN | MUSB_TXCSR_TXPKTRDY);
+               musb_writew(epio, MUSB_TXCSR, csr);
+               DBG(20, "underrun on ep%d, req %p\n", epnum, request);
+       }
+
+       if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
+               /*
+                * SHOULD NOT HAPPEN... has with CPPI though, after
+                * changing SENDSTALL (and other cases); harmless?
                 */
-               if (csr & MUSB_TXCSR_P_SENTSTALL) {
-                       csr |= MUSB_TXCSR_P_WZC_BITS;
-                       csr &= ~MUSB_TXCSR_P_SENTSTALL;
-                       musb_writew(epio, MUSB_TXCSR, csr);
-                       break;
-               }
+               DBG(5, "%s dma still busy?\n", musb_ep->end_point.name);
+               return;
+       }
 
-               if (csr & MUSB_TXCSR_P_UNDERRUN) {
-                       /* we NAKed, no big deal ... little reason to care */
+       if (request) {
+               u8      is_dma = 0;
+
+               if (dma && (csr & MUSB_TXCSR_DMAENAB)) {
+                       is_dma = 1;
                        csr |= MUSB_TXCSR_P_WZC_BITS;
-                       csr &= ~(MUSB_TXCSR_P_UNDERRUN
-                                       | MUSB_TXCSR_TXPKTRDY);
+                       csr &= ~(MUSB_TXCSR_DMAENAB | MUSB_TXCSR_P_UNDERRUN |
+                                MUSB_TXCSR_TXPKTRDY);
                        musb_writew(epio, MUSB_TXCSR, csr);
-                       DBG(20, "underrun on ep%d, req %p\n", epnum, request);
+                       /* Ensure writebuffer is empty. */
+                       csr = musb_readw(epio, MUSB_TXCSR);
+                       request->actual += musb_ep->dma->actual_len;
+                       DBG(4, "TXCSR%d %04x, DMA off, len %zu, req %p\n",
+                               epnum, csr, musb_ep->dma->actual_len, request);
                }
 
-               if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
-                       /* SHOULD NOT HAPPEN ... has with cppi though, after
-                        * changing SENDSTALL (and other cases); harmless?
+               if (is_dma || request->actual == request->length) {
+                       /*
+                        * First, maybe a terminating short packet. Some DMA
+                        * engines might handle this by themselves.
                         */
-                       DBG(5, "%s dma still busy?\n", musb_ep->end_point.name);
-                       break;
-               }
-
-               if (request) {
-                       u8      is_dma = 0;
-
-                       if (dma && (csr & MUSB_TXCSR_DMAENAB)) {
-                               is_dma = 1;
-                               csr |= MUSB_TXCSR_P_WZC_BITS;
-                               csr &= ~(MUSB_TXCSR_DMAENAB
-                                               | MUSB_TXCSR_P_UNDERRUN
-                                               | MUSB_TXCSR_TXPKTRDY);
-                               musb_writew(epio, MUSB_TXCSR, csr);
-                               /* ensure writebuffer is empty */
-                               csr = musb_readw(epio, MUSB_TXCSR);
-                               request->actual += musb_ep->dma->actual_len;
-                               DBG(4, "TXCSR%d %04x, dma off, "
-                                               "len %zu, req %p\n",
-                                       epnum, csr,
-                                       musb_ep->dma->actual_len,
-                                       request);
-                       }
-
-                       if (is_dma || request->actual == request->length) {
-
-                               /* First, maybe a terminating short packet.
-                                * Some DMA engines might handle this by
-                                * themselves.
-                                */
-                               if ((request->zero
-                                               && request->length
-                                               && (request->length
-                                                       % musb_ep->packet_sz)
-                                                       == 0)
+                       if ((request->zero && request->length
+                               && request->length % musb_ep->packet_sz == 0)
 #ifdef CONFIG_USB_INVENTRA_DMA
-                                       || (is_dma &&
-                                               ((!dma->desired_mode) ||
-                                                   (request->actual &
-                                                   (musb_ep->packet_sz - 1))))
+                               || (is_dma && (!dma->desired_mode ||
+                                       (request->actual &
+                                               (musb_ep->packet_sz - 1))))
 #endif
-                               ) {
-                                       /* on dma completion, fifo may not
-                                        * be available yet ...
-                                        */
-                                       if (csr & MUSB_TXCSR_TXPKTRDY)
-                                               break;
-
-                                       DBG(4, "sending zero pkt\n");
-                                       musb_writew(epio, MUSB_TXCSR,
-                                                       MUSB_TXCSR_MODE
-                                                       | MUSB_TXCSR_TXPKTRDY);
-                                       request->zero = 0;
-                               }
-
-                               /* ... or if not, then complete it */
-                               musb_g_giveback(musb_ep, request, 0);
-
-                               /* kickstart next transfer if appropriate;
-                                * the packet that just completed might not
-                                * be transmitted for hours or days.
-                                * REVISIT for double buffering...
-                                * FIXME revisit for stalls too...
+                       ) {
+                               /*
+                                * On DMA completion, FIFO may not be
+                                * available yet...
                                 */
-                               musb_ep_select(mbase, epnum);
-                               csr = musb_readw(epio, MUSB_TXCSR);
-                               if (csr & MUSB_TXCSR_FIFONOTEMPTY)
-                                       break;
-                               request = musb_ep->desc
-                                               ? next_request(musb_ep)
-                                               : NULL;
-                               if (!request) {
-                                       DBG(4, "%s idle now\n",
-                                               musb_ep->end_point.name);
-                                       break;
-                               }
+                               if (csr & MUSB_TXCSR_TXPKTRDY)
+                                       return;
+
+                               DBG(4, "sending zero pkt\n");
+                               musb_writew(epio, MUSB_TXCSR, MUSB_TXCSR_MODE
+                                               | MUSB_TXCSR_TXPKTRDY);
+                               request->zero = 0;
                        }
 
-                       txstate(musb, to_musb_request(request));
+                       /* ... or if not, then complete it. */
+                       musb_g_giveback(musb_ep, request, 0);
+
+                       /*
+                        * Kickstart next transfer if appropriate;
+                        * the packet that just completed might not
+                        * be transmitted for hours or days.
+                        * REVISIT for double buffering...
+                        * FIXME revisit for stalls too...
+                        */
+                       musb_ep_select(mbase, epnum);
+                       csr = musb_readw(epio, MUSB_TXCSR);
+                       if (csr & MUSB_TXCSR_FIFONOTEMPTY)
+                               return;
+
+                       if (!musb_ep->desc) {
+                               DBG(4, "%s idle now\n",
+                                       musb_ep->end_point.name);
+                               return;
+                       } else
+                               request = next_request(musb_ep);
                }
 
-       } while (0);
+               txstate(musb, to_musb_request(request));
+       }
 }
 
 /* ------------------------------------------------------------ */