[Sound-open-firmware] [PATCH 3/5] host: host_copy(): add handle for capture

[Liam Girdwood]

On Wed, 2017-02-15 at 18:07 +0800, Keyon Jie wrote:
> For playback, don't copy if there is no available data;
> For capture, don't copy if there is no free host side buffer.
> 
> Signed-off-by: Keyon Jie <yang.jie at linux.intel.com>
> ---
>  src/audio/host.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/src/audio/host.c b/src/audio/host.c
> index b604ddc..61d2b62 100644
> --- a/src/audio/host.c
> +++ b/src/audio/host.c
> @@ -815,7 +815,10 @@ static int host_copy(struct comp_dev *dev)
>  	if (dev->state != COMP_STATE_RUNNING)
>  		return 0;
>  
> -	if (hd->host_avail == 0)
> +	/* don't copy if the host side buffer is not ready */
> +	if (((hd->params.direction == STREAM_DIRECTION_PLAYBACK)
> +	    &&  (hd->host_avail == 0)) || ((hd->host_free == 0) &&
> +	    (hd->params.direction == STREAM_DIRECTION_CAPTURE)))
>  		return 0;
>  

Better to do for readability :-

 if (dir == P && host_avail == 0)
	return 0;
 if (dir == C && host_free == 0)
	return 0;

>  	/* do DMA transfer */