PCM devices are created for FE dai links with 'no-pcm' flag as '0'. Such DAI links have CPU component which implement either pcm_construct() or pcm_new() at component or dai level respectively. Based on this, current patch exposes a helper function to identify such components and populate 'no_pcm' flag for DPCM DAI link. This helps to have BE<->BE component links where PCM devices need not be created for CPU component involved in such links. Signed-off-by: Sameer Pujar <spujar@xxxxxxxxxx> --- sound/soc/generic/audio-graph-card.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/sound/soc/generic/audio-graph-card.c b/sound/soc/generic/audio-graph-card.c index 1e20562..93bddf6 100644 --- a/sound/soc/generic/audio-graph-card.c +++ b/sound/soc/generic/audio-graph-card.c @@ -111,6 +111,17 @@ static int graph_get_dai_id(struct device_node *ep) return id; } +static bool soc_component_is_pcm(struct snd_soc_dai_link_component *dlc) +{ + struct snd_soc_dai *dai = snd_soc_find_dai(dlc); + + if (dai && (dai->component->driver->pcm_construct || + dai->driver->pcm_new)) + return true; + + return false; +} + static int asoc_simple_parse_dai(struct device_node *ep, struct snd_soc_dai_link_component *dlc, int *is_single_link) @@ -259,6 +270,16 @@ static int graph_dai_link_of_dpcm(struct asoc_simple_priv *priv, if (ret < 0) goto out_put_node; + /* + * In BE<->BE connections it is not required to create + * PCM devices at CPU end of the dai link and thus 'no_pcm' + * flag needs to be set. It is useful when there are many + * BE components and some of these have to be connected to + * form a valid audio path. + */ + if (!soc_component_is_pcm(cpus)) + dai_link->no_pcm = 1; + /* card->num_links includes Codec */ asoc_simple_canonicalize_cpu(dai_link, is_single_links); } else { -- 2.7.4