[alsa-devel] [PATCH] ASoC: audio-graph-card: don't select DPCM via audio-graph-card

[Kuninori Morimoto]

From: Kuninori Morimoto <kuninori.morimoto.gx at renesas.com>

commit ae3cb5790906b ("ASoC: audio-graph-card: merge
audio-graph-scu-card") merged audio-graph-scu-card which can
handle DPCM into audio-graph-card.

By this patch, the judgement to select "normal sound card" or
"DPCM sound card" is based on its OF-graph endpoint connection.
But, because of it, existing "audio-graph-card" user who is
assuming "normal sound card" might select DPCM unintentionally.

To solve this issue, this patch allows "audio-graph-card" user
can select "normal sound card", and "audio-graph-scu-card" user
can select both "normal sound card" and "DPCM sound card".
This keeps compatibility collectry.

Reported-by: Arnaud Pouliquen <arnaud.pouliquen at st.com>
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx at renesas.com>
---
 sound/soc/generic/audio-graph-card.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/sound/soc/generic/audio-graph-card.c b/sound/soc/generic/audio-graph-card.c
index bb12351..69bc484 100644
--- a/sound/soc/generic/audio-graph-card.c
+++ b/sound/soc/generic/audio-graph-card.c
@@ -20,6 +20,8 @@
 #include <linux/string.h>
 #include <sound/simple_card_utils.h>
 
+#define DPCM_SELECTABLE 1
+
 struct graph_priv {
 	struct snd_soc_card snd_card;
 	struct graph_dai_props {
@@ -440,6 +442,7 @@ static int graph_for_each_link(struct graph_priv *priv,
 	struct device_node *codec_port;
 	struct device_node *codec_port_old = NULL;
 	struct asoc_simple_card_data adata;
+	uintptr_t dpcm_selectable = (uintptr_t)of_device_get_match_data(dev);
 	int rc, ret;
 
 	/* loop for all listed CPU port */
@@ -470,8 +473,9 @@ static int graph_for_each_link(struct graph_priv *priv,
 			 * if Codec port has many endpoints,
 			 * or has convert-xxx property
 			 */
-			if ((of_get_child_count(codec_port) > 1) ||
-			    adata.convert_rate || adata.convert_channels)
+			if (dpcm_selectable &&
+			    ((of_get_child_count(codec_port) > 1) ||
+			     adata.convert_rate || adata.convert_channels))
 				ret = func_dpcm(priv, cpu_ep, codec_ep, li,
 						(codec_port_old == codec_port));
 			/* else normal sound */
@@ -732,7 +736,8 @@ static int graph_remove(struct platform_device *pdev)
 
 static const struct of_device_id graph_of_match[] = {
 	{ .compatible = "audio-graph-card", },
-	{ .compatible = "audio-graph-scu-card", },
+	{ .compatible = "audio-graph-scu-card",
+	  .data = (void *)DPCM_SELECTABLE },
 	{},
 };
 MODULE_DEVICE_TABLE(of, graph_of_match);
-- 
2.7.4