From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jeff Garzik <jeff@garzik.org>
Subject: Re: [PATCH 14/19] dmaengine: add dma_sync_wait
Date: Mon, 11 Sep 2006 19:52:07 -0400
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To: Dan Williams <dan.j.williams@intel.com>
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Dan Williams wrote:
> From: Dan Williams <dan.j.williams@intel.com>
> 
> dma_sync_wait is a common routine to live wait for a dma operation to
> complete.
> 
> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
> ---
> 
>  include/linux/dmaengine.h |   12 ++++++++++++
>  1 files changed, 12 insertions(+), 0 deletions(-)
> 
> diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
> index 9fd6cbd..0a70c9e 100644
> --- a/include/linux/dmaengine.h
> +++ b/include/linux/dmaengine.h
> @@ -750,6 +750,18 @@ static inline void dma_async_unmap_singl
>  	chan->device->unmap_single(chan, handle, size, direction);
>  }
>  
> +static inline enum dma_status dma_sync_wait(struct dma_chan *chan,
> +						dma_cookie_t cookie)
> +{
> +	enum dma_status status;
> +	dma_async_issue_pending(chan);
> +	do {
> +		status = dma_async_operation_complete(chan, cookie, NULL, NULL);
> +	} while (status == DMA_IN_PROGRESS);
> +
> +	return status;

Where are the timeouts, etc.?  Looks like an infinite loop to me, in the 
worst case.

	Jeff