[PATCH 2/4] usb: musb: gadget: do *unmap_dma_buffer* only for valid DMA addr

From: Kishon Vijay Abraham I
Date: Fri Mar 15 2013 - 09:29:33 EST


musb does not use DMA buffer for ep0 but it uses the same giveback
function *musb_g_giveback* for all endpoints (*musb_g_ep0_giveback* calls
*musb_g_giveback*). So for ep0 case request.dma will be '0'
and will result in kernel OOPS if tried to *unmap_dma_buffer* for requests in
ep0. Fixed it by doing *unmap_dma_buffer* only for valid DMA addr.

Signed-off-by: Kishon Vijay Abraham I <kishon@xxxxxx>
---
drivers/usb/musb/musb_gadget.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/musb/musb_gadget.c b/drivers/usb/musb/musb_gadget.c
index c454375..ec3cf29 100644
--- a/drivers/usb/musb/musb_gadget.c
+++ b/drivers/usb/musb/musb_gadget.c
@@ -107,7 +107,10 @@ __acquires(ep->musb->lock)

ep->busy = 1;
spin_unlock(&musb->lock);
- unmap_dma_buffer(req, musb);
+
+ if (request->dma)
+ unmap_dma_buffer(req, musb);
+
if (request->status == 0)
dev_dbg(musb->controller, "%s done request %p, %d/%d\n",
ep->end_point.name, request,
--
1.7.10.4

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