[Sound-open-firmware] [PATCH] sof: Add volume component state check

[Ranjani Sridharan]

On Tue, 2018-03-27 at 09:42 +0800, Wu Zhigang wrote:
> Add the state check in volume_copy function,
> this can low down the xrun error possibility:
> For example:
> when firmware receive the PAUSE command, the HOST and VOLUME
> component are set to PAUSE state. at this time DMA IRQ happen,
> the pipeline is scheduled. host_copy() function will be called,
> but jump out immediately because of PAUSE state. but volume_copy()
> did not have this state check, the xrun will happen.
> 
> Signed-off-by: Wu Zhigang <zhigang.wu at linux.intel.com>
> Reviewed-by: Keyon Jie <yang.jie at linux.intel.com>
> 
> ---
> Tested with
> apl-gpmrb board
> 
> kernel: https://github.com/plbossart/sound.gitt  branch: topic/sof-
> v4.14
> 	4881a4bd906f8b52bebd209b88ff920005550d53
> 
> firmware: git://git.alsa-project.org/sound-open-firmware.git  branch: 
> 1.1-stable
>         1f8c6c4d2018aac6994c75f60cee54765435d424
> 
> tools:	branch: 1.1-stable
> 	cc91c73aa3e91eea35abdeb76d578b97f718feff
> ---
>  src/audio/volume.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/src/audio/volume.c b/src/audio/volume.c
> index df926c5..2652765 100644
> --- a/src/audio/volume.c
> +++ b/src/audio/volume.c
> @@ -836,6 +836,9 @@ static int volume_copy(struct comp_dev *dev)
>  
>  	tracev_volume("cpy");
>  
> +	if (dev->state != COMP_STATE_ACTIVE)
> +		return 0;

Zhigang, pipeline_copy_from_upstream() and
pipeline_copy_to_downstream() both have the check to make sure we
propogate copy only if the component is active. Will those not handle
this situation as well? 

> +
>  	/* volume components will only ever have 1 source and 1 sink
> buffer */
>  	source = list_first_item(&dev->bsource_list, struct
> comp_buffer, sink_list);
>  	sink = list_first_item(&dev->bsink_list, struct comp_buffer,
> source_list);