ASoC: SOF: Intel: hda: reserve host DMA channel for hostless streams

Due to the HW programming sequence requirement that the host
and link DMA channels need to be coupled/decoupled during pcm
hw_params, the host DMA channel corresponding to the link
DMA channel in use for hostless streams needs to be reserved.
This is achieved by adding a host_reserved flag in the
sof_intel_hda_stream structure which is checked when assigning
a host DMA channel.

Signed-off-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This commit is contained in:
Ranjani Sridharan 2019-06-12 12:23:37 -05:00 committed by Mark Brown
parent bdf4ad3fd0
commit 6b2239e333
No known key found for this signature in database
GPG Key ID: 24D68B725D5487D0
3 changed files with 20 additions and 2 deletions

View File

@ -75,7 +75,7 @@ static struct hdac_ext_stream *
hda_stream = hstream_to_sof_hda_stream(hstream);
/* check if available */
/* check if link is available */
if (!hstream->link_locked) {
if (stream->opened) {
/*
@ -89,6 +89,12 @@ static struct hdac_ext_stream *
}
} else {
res = hstream;
/*
* This must be a hostless stream.
* So reserve the host DMA channel.
*/
hda_stream->host_reserved = 1;
break;
}
}
@ -368,6 +374,9 @@ static int hda_link_hw_free(struct snd_pcm_substream *substream,
snd_hdac_ext_stream_release(link_dev, HDAC_EXT_STREAM_TYPE_LINK);
link_dev->link_prepared = 0;
/* free the host DMA channel reserved by hostless streams */
hda_stream->host_reserved = 0;
return 0;
}

View File

@ -155,6 +155,7 @@ struct hdac_ext_stream *
hda_dsp_stream_get(struct snd_sof_dev *sdev, int direction)
{
struct hdac_bus *bus = sof_to_bus(sdev);
struct sof_intel_hda_stream *hda_stream;
struct hdac_ext_stream *stream = NULL;
struct hdac_stream *s;
@ -163,8 +164,15 @@ hda_dsp_stream_get(struct snd_sof_dev *sdev, int direction)
/* get an unused stream */
list_for_each_entry(s, &bus->stream_list, list) {
if (s->direction == direction && !s->opened) {
s->opened = true;
stream = stream_to_hdac_ext_stream(s);
hda_stream = container_of(stream,
struct sof_intel_hda_stream,
hda_stream);
/* check if the host DMA channel is reserved */
if (hda_stream->host_reserved)
continue;
s->opened = true;
break;
}
}

View File

@ -413,6 +413,7 @@ struct sof_intel_hda_stream {
struct hdac_ext_stream hda_stream;
struct sof_intel_stream stream;
int hw_params_upon_resume; /* set up hw_params upon resume */
int host_reserved; /* reserve host DMA channel */
};
#define hstream_to_sof_hda_stream(hstream) \