diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/usb/musb/musb_host.c | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/drivers/usb/musb/musb_host.c b/drivers/usb/musb/musb_host.c index 4bb717d0bd4..29b5149f575 100644 --- a/drivers/usb/musb/musb_host.c +++ b/drivers/usb/musb/musb_host.c @@ -693,6 +693,8 @@ static void musb_ep_program(struct musb *musb, u8 epnum, void __iomem *epio = hw_ep->regs; struct musb_qh *qh = musb_ep_get_qh(hw_ep, !is_out); u16 packet_sz = qh->maxpacket; + u8 use_dma = 1; + u16 csr; dev_dbg(musb->controller, "%s hw%d urb %p spd%d dev%d ep%d%s " "h_addr%02x h_port%02x bytes %d\n", @@ -704,9 +706,17 @@ static void musb_ep_program(struct musb *musb, u8 epnum, musb_ep_select(mbase, epnum); + if (is_out && !len) { + use_dma = 0; + csr = musb_readw(epio, MUSB_TXCSR); + csr &= ~MUSB_TXCSR_DMAENAB; + musb_writew(epio, MUSB_TXCSR, csr); + hw_ep->tx_channel = NULL; + } + /* candidate for DMA? */ dma_controller = musb->dma_controller; - if (is_dma_capable() && epnum && dma_controller) { + if (use_dma && is_dma_capable() && epnum && dma_controller) { dma_channel = is_out ? hw_ep->tx_channel : hw_ep->rx_channel; if (!dma_channel) { dma_channel = dma_controller->channel_alloc( |