At Thu, 07 Aug 2008 13:51:55 -0500, Timur Tabi wrote:

In my _pointer callback function, I have this:

printk(KERN_INFO "%s:%u substream->pcm->dev=%p, substream->pcm->card->dev=%p\n", __func__, __LINE__, substream->pcm->dev, substream->pcm->card->dev);

During playback, it displays this:

fsl_dma_pointer:698 substream->pcm->dev=00000000, substream->pcm->card->dev=dfa50a08

Why is substream->pcm->dev == NULL? What's the point of having this field if you're not going to use it?

It's provided to use a different device for PCM than card->dev. An example is found in AOA drivers.

Takashi