ALSA: Restore support for DMAless DAIs on PXA

Used for applications such as direct bluetooth connections on
smartphones which don't go via the CPU. This used to be supported
before the refactoring to share code but this check was removed
during that move.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

diff --git a/sound/arm/pxa2xx-pcm-lib.c b/sound/arm/pxa2xx-pcm-lib.c
index 6205f37d547ce80e0315be9d97fbc7ce7fa9ebe5..743ac6a2906598fdbd70a04f6a3c6910fd86fdfe 100644 (file)
--- a/sound/arm/pxa2xx-pcm-lib.c
+++ b/sound/arm/pxa2xx-pcm-lib.c
@@ -136,6 +136,9 @@ int __pxa2xx_pcm_prepare(struct snd_pcm_substream *substream)
 {
        struct pxa2xx_runtime_data *prtd = substream->runtime->private_data;
 
+       if (!prtd || !prtd->params)
+               return 0;
+
        DCSR(prtd->dma_ch) &= ~DCSR_RUN;
        DCSR(prtd->dma_ch) = 0;
        DCMD(prtd->dma_ch) = 0;