sound/soc/sof/stream-ipc.c

Source file repositories/reference/linux-study-clean/sound/soc/sof/stream-ipc.c

File Facts

System
Linux kernel
Corpus path
sound/soc/sof/stream-ipc.c
Extension
.c
Size
3350 bytes
Lines
132
Domain
Driver Families
Bucket
sound/soc
Inferred role
Driver Families: exported/initcall integration point
Status
integration implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

struct sof_stream {
	size_t posn_offset;
};

/* Mailbox-based Generic IPC implementation */
int sof_ipc_msg_data(struct snd_sof_dev *sdev,
		     struct snd_sof_pcm_stream *sps,
		     void *p, size_t sz)
{
	if (!sps || !sdev->stream_box.size) {
		snd_sof_dsp_mailbox_read(sdev, sdev->dsp_box.offset, p, sz);
	} else {
		size_t posn_offset;

		if (sps->substream) {
			struct sof_stream *stream = sps->substream->runtime->private_data;

			/* The stream might already be closed */
			if (!stream)
				return -ESTRPIPE;

			posn_offset = stream->posn_offset;
		} else if (sps->cstream) {

			struct sof_compr_stream *sstream = sps->cstream->runtime->private_data;

			if (!sstream)
				return -ESTRPIPE;

			posn_offset = sstream->posn_offset;

		} else {
			dev_err(sdev->dev, "%s: No stream opened\n", __func__);
			return -EINVAL;
		}

		snd_sof_dsp_mailbox_read(sdev, posn_offset, p, sz);
	}

	return 0;
}
EXPORT_SYMBOL(sof_ipc_msg_data);

int sof_set_stream_data_offset(struct snd_sof_dev *sdev,
			       struct snd_sof_pcm_stream *sps,
			       size_t posn_offset)
{
	/* check if offset is overflow or it is not aligned */
	if (posn_offset > sdev->stream_box.size ||
	    posn_offset % sizeof(struct sof_ipc_stream_posn) != 0)
		return -EINVAL;

	posn_offset += sdev->stream_box.offset;

	if (sps->substream) {
		struct sof_stream *stream = sps->substream->runtime->private_data;

		stream->posn_offset = posn_offset;
		dev_dbg(sdev->dev, "pcm: stream dir %d, posn mailbox offset is %zu",
			sps->substream->stream, posn_offset);
	} else if (sps->cstream) {
		struct sof_compr_stream *sstream = sps->cstream->runtime->private_data;

		sstream->posn_offset = posn_offset;
		dev_dbg(sdev->dev, "compr: stream dir %d, posn mailbox offset is %zu",
			sps->cstream->direction, posn_offset);
	} else {
		dev_err(sdev->dev, "No stream opened");
		return -EINVAL;
	}

	return 0;
}
EXPORT_SYMBOL(sof_set_stream_data_offset);

int sof_stream_pcm_open(struct snd_sof_dev *sdev,
			struct snd_pcm_substream *substream)
{
	struct sof_stream *stream = kmalloc_obj(*stream);

	if (!stream)
		return -ENOMEM;

	/* binding pcm substream to hda stream */
	substream->runtime->private_data = stream;

	/* align to DMA minimum transfer size */
	snd_pcm_hw_constraint_step(substream->runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_BYTES, 4);

	/* avoid circular buffer wrap in middle of period */

Annotation

Implementation Notes