From: Ajay Kumar Gupta Date: Fri, 20 Jul 2012 05:37:23 +0000 (+0530) Subject: usb: musb: gadget: don't program dma for zero byte tx X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=d17d535fec07dbd298b3f65838ec8d63c26ab360;p=linux-beck.git usb: musb: gadget: don't program dma for zero byte tx This is to reduce the overhead of dma programming for zero byte transmit as same can be done using pio mode. Signed-off-by: Ajay Kumar Gupta Signed-off-by: Felipe Balbi --- diff --git a/drivers/usb/musb/musb_gadget.c b/drivers/usb/musb/musb_gadget.c index 49d7bee7dbde..8d2cce106f04 100644 --- a/drivers/usb/musb/musb_gadget.c +++ b/drivers/usb/musb/musb_gadget.c @@ -373,7 +373,7 @@ static void txstate(struct musb *musb, struct musb_request *req) request_size = min_t(size_t, request->length - request->actual, musb_ep->dma->max_len); - use_dma = (request->dma != DMA_ADDR_INVALID); + use_dma = (request->dma != DMA_ADDR_INVALID && request_size); /* MUSB_TXCSR_P_ISO is still set correctly */