diff --git a/sound/arm/pxa2xx-pcm-lib.c b/sound/arm/pxa2xx-pcm-lib.c
index 8808b82311b1eb207a2fb3306548666ad6dd6a8b..76e0d56950751a8a60074d5a9a7df6232a1ee472 100644
--- a/sound/arm/pxa2xx-pcm-lib.c
+++ b/sound/arm/pxa2xx-pcm-lib.c
@@ -140,6 +140,9 @@ int __pxa2xx_pcm_prepare(struct snd_pcm_substream *substream)
 	if (!prtd || !prtd->params)
 		return 0;
 
+	if (prtd->dma_ch == -1)
+		return -EINVAL;
+
 	DCSR(prtd->dma_ch) &= ~DCSR_RUN;
 	DCSR(prtd->dma_ch) = 0;
 	DCMD(prtd->dma_ch) = 0;
diff --git a/sound/soc/pxa/pxa2xx-pcm.c b/sound/soc/pxa/pxa2xx-pcm.c
index 02fb66416ddc894c7abdfd2fa52cddc3eb717225..2ce0b2d891d5081df50ed6c677ef835eab845b94 100644
--- a/sound/soc/pxa/pxa2xx-pcm.c
+++ b/sound/soc/pxa/pxa2xx-pcm.c
@@ -65,6 +65,7 @@ static int pxa2xx_pcm_hw_free(struct snd_pcm_substream *substream)
 	if (prtd->dma_ch >= 0) {
 		pxa_free_dma(prtd->dma_ch);
 		prtd->dma_ch = -1;
+		prtd->params = NULL;
 	}
 
 	return 0;