1 files changed, 38 insertions, 28 deletions

diff --git a/drivers/usb/musb/musbhsdma.c b/drivers/usb/musb/musbhsdma.c
index 8662e9e159c3..5e83f96d6b77 100644
--- a/drivers/usb/musb/musbhsdma.c
+++ b/drivers/usb/musb/musbhsdma.c
@@ -195,30 +195,32 @@ static int dma_channel_abort(struct dma_channel *channel)
         void __iomem *mbase = musb_channel->controller->base;
 
         u8 bchannel = musb_channel->idx;
+        int offset;
         u16 csr;
 
         if (channel->status == MUSB_DMA_STATUS_BUSY) {
                 if (musb_channel->transmit) {
-
-                        csr = musb_readw(mbase,
-                                MUSB_EP_OFFSET(musb_channel->epnum,
-                                                MUSB_TXCSR));
-                        csr &= ~(MUSB_TXCSR_AUTOSET |
-                                 MUSB_TXCSR_DMAENAB |
-                                 MUSB_TXCSR_DMAMODE);
-                        musb_writew(mbase,
-                                MUSB_EP_OFFSET(musb_channel->epnum, MUSB_TXCSR),
-                                csr);
+                        offset = MUSB_EP_OFFSET(musb_channel->epnum,
+                                                MUSB_TXCSR);
+
+                        /*
+                         * The programming guide says that we must clear
+                         * the DMAENAB bit before the DMAMODE bit...
+                         */
+                        csr = musb_readw(mbase, offset);
+                        csr &= ~(MUSB_TXCSR_AUTOSET | MUSB_TXCSR_DMAENAB);
+                        musb_writew(mbase, offset, csr);
+                        csr &= ~MUSB_TXCSR_DMAMODE;
+                        musb_writew(mbase, offset, csr);
                 } else {
-                        csr = musb_readw(mbase,
-                                MUSB_EP_OFFSET(musb_channel->epnum,
-                                                MUSB_RXCSR));
+                        offset = MUSB_EP_OFFSET(musb_channel->epnum,
+                                                MUSB_RXCSR);
+
+                        csr = musb_readw(mbase, offset);
                         csr &= ~(MUSB_RXCSR_AUTOCLEAR |
                                  MUSB_RXCSR_DMAENAB |
                                  MUSB_RXCSR_DMAMODE);
-                        musb_writew(mbase,
-                                MUSB_EP_OFFSET(musb_channel->epnum, MUSB_RXCSR),
-                                csr);
+                        musb_writew(mbase, offset, csr);
                 }
 
                 musb_writew(mbase,
@@ -296,20 +298,28 @@ static irqreturn_t dma_controller_irq(int irq, void *private_data)
                                         && ((channel->desired_mode == 0)
                                             || (channel->actual_len &
                                             (musb_channel->max_packet_sz - 1)))
-                                         ) {
+                                    ) {
+                                        u8  epnum  = musb_channel->epnum;
+                                        int offset = MUSB_EP_OFFSET(epnum,
+                                                                    MUSB_TXCSR);
+                                        u16 txcsr;
+
+                                        /*
+                                         * The programming guide says that we
+                                         * must clear DMAENAB before DMAMODE.
+                                         */
+                                        musb_ep_select(mbase, epnum);
+                                        txcsr = musb_readw(mbase, offset);
+                                        txcsr &= ~(MUSB_TXCSR_DMAENAB
+                                                        | MUSB_TXCSR_AUTOSET);
+                                        musb_writew(mbase, offset, txcsr);
                                         /* Send out the packet */
-                                        musb_ep_select(mbase,
-                                                musb_channel->epnum);
-                                        musb_writew(mbase, MUSB_EP_OFFSET(
-                                                        musb_channel->epnum,
-                                                        MUSB_TXCSR),
-                                                MUSB_TXCSR_TXPKTRDY);
-                                } else {
-                                        musb_dma_completion(
-                                                musb,
-                                                musb_channel->epnum,
-                                                musb_channel->transmit);
+                                        txcsr &= ~MUSB_TXCSR_DMAMODE;
+                                        txcsr |=  MUSB_TXCSR_TXPKTRDY;
+                                        musb_writew(mbase, offset, txcsr);
                                 }
+                                musb_dma_completion(musb, musb_channel->epnum,
+                                                    musb_channel->transmit);
                         }
                 }
         }