[PATCH v3 1/6] ASoC: dmaengine: do not use a NULL prepare_slave_config() callback

[Codrin Ciubotariu <codrin.ciubotariu@microchip.com>]

Even if struct snd_dmaengine_pcm_config is used, prepare_slave_config()
callback might not be set. Check if this callback is set before using it.

Fixes: fa654e085300 ("ASoC: dmaengine-pcm: Provide default config")
Signed-off-by: Codrin Ciubotariu <codrin.ciubotariu@microchip.com>
---

Changes in v2,v3:
 - none

 sound/soc/soc-generic-dmaengine-pcm.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/sound/soc/soc-generic-dmaengine-pcm.c b/sound/soc/soc-generic-dmaengine-pcm.c
index 285441d6aeed..2ab2ddc1294d 100644
--- a/sound/soc/soc-generic-dmaengine-pcm.c
+++ b/sound/soc/soc-generic-dmaengine-pcm.c
@@ -86,10 +86,10 @@ static int dmaengine_pcm_hw_params(struct snd_soc_component *component,
 
 	memset(&slave_config, 0, sizeof(slave_config));
 
-	if (!pcm->config)
-		prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config;
-	else
+	if (pcm->config && pcm->config->prepare_slave_config)
 		prepare_slave_config = pcm->config->prepare_slave_config;
+	else
+		prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config;
 
 	if (prepare_slave_config) {
 		int ret = prepare_slave_config(substream, params, &slave_config);
-- 
2.32.0