ALSA: pcm: Fix mmap breakage without explicit buffer setup

[platform/kernel/linux-rpi.git] / sound / core / pcm_native.c

diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
index c88c431..71323d8 100644 (file)
--- a/sound/core/pcm_native.c
+++ b/sound/core/pcm_native.c
@@ -246,12 +246,21 @@ static bool hw_support_mmap(struct snd_pcm_substream *substream)
        if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_MMAP))
                return false;
 
-       if (substream->ops->mmap ||
-           (substream->dma_buffer.dev.type != SNDRV_DMA_TYPE_DEV &&
-            substream->dma_buffer.dev.type != SNDRV_DMA_TYPE_DEV_UC))
+       if (substream->ops->mmap || substream->ops->page)
                return true;
 
-       return dma_can_mmap(substream->dma_buffer.dev.dev);
+       switch (substream->dma_buffer.dev.type) {
+       case SNDRV_DMA_TYPE_UNKNOWN:
+               /* we can't know the device, so just assume that the driver does
+                * everything right
+                */
+               return true;
+       case SNDRV_DMA_TYPE_CONTINUOUS:
+       case SNDRV_DMA_TYPE_VMALLOC:
+               return true;
+       default:
+               return dma_can_mmap(substream->dma_buffer.dev.dev);
+       }
 }
 
 static int constrain_mask_params(struct snd_pcm_substream *substream,
@@ -3669,6 +3678,8 @@ static vm_fault_t snd_pcm_mmap_data_fault(struct vm_fault *vmf)
                return VM_FAULT_SIGBUS;
        if (substream->ops->page)
                page = substream->ops->page(substream, offset);
+       else if (!snd_pcm_get_dma_buf(substream))
+               page = virt_to_page(runtime->dma_area + offset);
        else
                page = snd_sgbuf_get_page(snd_pcm_get_dma_buf(substream), offset);
        if (!page)