From david-b@pacbell.net Sun Oct 16 15:11:06 2005 Date: Sun, 16 Oct 2005 15:06:51 -0700 From: David Brownell To: greg@kroah.com Subject: [patch 2.6.15] omap_udc dma off-by-one fix Message-Id: <20051016220651.14B96BF6B9@adsl-69-107-32-110.dsl.pltn13.pacbell.net> The change to make DMA work two bytes at a time omitted an important tweak that affects the file_storage gadget: it needs to recognize when the host writes an odd number of bytes. (The network layer ignores such extra bytes.) This patch resolves that issue by checking the relevant bit and adjusting the rx byte count, so that for example a legal 13 byte request doesn't morph into an illegal 14 byte one any more. Signed-off-by: David Brownell Signed-off-by: Greg Kroah-Hartman --- drivers/usb/gadget/omap_udc.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) --- gregkh-2.6.orig/drivers/usb/gadget/omap_udc.c +++ gregkh-2.6/drivers/usb/gadget/omap_udc.c @@ -691,7 +691,7 @@ static void next_out_dma(struct omap_ep } static void -finish_out_dma(struct omap_ep *ep, struct omap_req *req, int status) +finish_out_dma(struct omap_ep *ep, struct omap_req *req, int status, int one) { u16 count; @@ -699,6 +699,8 @@ finish_out_dma(struct omap_ep *ep, struc ep->dma_counter = (u16) (req->req.dma + req->req.actual); count = dma_dest_len(ep, req->req.dma + req->req.actual); count += req->req.actual; + if (one) + count--; if (count <= req->req.length) req->req.actual = count; @@ -747,7 +749,7 @@ static void dma_irq(struct omap_udc *udc if (!list_empty(&ep->queue)) { req = container_of(ep->queue.next, struct omap_req, queue); - finish_out_dma(ep, req, 0); + finish_out_dma(ep, req, 0, dman_stat & UDC_DMA_RX_SB); } UDC_IRQ_SRC_REG = UDC_RXN_EOT; @@ -925,7 +927,7 @@ static void dma_channel_release(struct o while (UDC_RXDMA_CFG_REG & mask) udelay(10); if (req) - finish_out_dma(ep, req, -ECONNRESET); + finish_out_dma(ep, req, -ECONNRESET, 0); } omap_free_dma(ep->lch); ep->dma_channel = 0;