Mark,
I'm testing your for-3.1 branch on the P1022DS, and I'm getting a kernel panic because a pointer is NULL where I don't expect it to be. In fsl_dma_new(), I have this code:
if (dai->driver->capture.channels_min) { ret = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, card->dev, fsl_dma_hardware.buffer_bytes_max, &pcm->streams[1].substream->dma_buffer); if (ret) { dev_err(card->dev, "can't alloc capture dma buffer\n"); snd_dma_free_pages(&pcm->streams[0].substream->dma_buffer); return ret; } }
I test for channels_min because the playback stream is registered separately from the capture stream, so I expect fsl_dma_new() to be called twice: once to initialize playback, and again to initialize capture.
In the past, if dai->driver->capture.channels_min was equal to some non-zero value, then pcm->streams[1].substream was also non-NULL. This appears no longer to be true. Now it appears that playback.channels_min and capture.channels_min are both set to 2 before fsl_dma_new() is called the first time.
I can change my code to do this:
if (pcm->streams[1].substream) { ret = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, card->dev, fsl_dma_hardware.buffer_bytes_max, &pcm->streams[1].substream->dma_buffer); if (ret) { dev_err(card->dev, "can't alloc capture dma buffer\n"); snd_dma_free_pages(&pcm->streams[0].substream->dma_buffer); return ret; } }
But before I do that, I'd like to know if this is a bug in ASoC, or just a new behavior that I need to handle.