From: Steven J. Magnani Date: Mon, 1 Mar 2010 05:18:16 +0000 (-0700) Subject: fsldma: Fix cookie issues X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=76bd061f5c7b7550cdaed68ad6219ea7cee288fc;p=GitHub%2Fmt8127%2Fandroid_kernel_alcatel_ttab.git fsldma: Fix cookie issues fsl_dma_update_completed_cookie() appears to calculate the last completed cookie incorrectly in the corner case where DMA on cookie 1 is in progress just following a cookie wrap. Signed-off-by: Steven J. Magnani Acked-by: Ira W. Snyder [dan.j.williams@intel.com: fix an integer overflow warning with INT_MAX] Signed-off-by: Dan Williams --- diff --git a/drivers/dma/fsldma.c b/drivers/dma/fsldma.c index 6541ebf8bf63..bbb4be5a3ff4 100644 --- a/drivers/dma/fsldma.c +++ b/drivers/dma/fsldma.c @@ -819,8 +819,11 @@ static void fsl_dma_update_completed_cookie(struct fsldma_chan *chan) desc = to_fsl_desc(chan->ld_running.prev); if (dma_is_idle(chan)) cookie = desc->async_tx.cookie; - else + else { cookie = desc->async_tx.cookie - 1; + if (unlikely(cookie < DMA_MIN_COOKIE)) + cookie = DMA_MAX_COOKIE; + } chan->completed_cookie = cookie; diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h index 78784982b33e..4d8d619f28bc 100644 --- a/include/linux/dmaengine.h +++ b/include/linux/dmaengine.h @@ -31,6 +31,8 @@ * if dma_cookie_t is >0 it's a DMA request cookie, <0 it's an error code */ typedef s32 dma_cookie_t; +#define DMA_MIN_COOKIE 1 +#define DMA_MAX_COOKIE INT_MAX #define dma_submit_error(cookie) ((cookie) < 0 ? 1 : 0)