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

[Wu Zhigang]

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.git  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;
+
 	/* 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);
-- 
2.11.0