[PATCH RFC] ASoC: simple-card-utils: fix priv->dai_props indexing

[Laurentiu Mihalcea <laurentiumihalcea111@xxxxxxxxx>]

From: Laurentiu Mihalcea <laurentiu.mihalcea@xxxxxxx>

As of commit cb18cd26039f ("ASoC: soc-core: do rtd->id trick at
snd_soc_add_pcm_runtime()") the ID stored in the PCM runtime data can
no longer be safely used to index the priv->dai_props array. This is
because the ID may be modified during snd_soc_add_pcm_runtime(), thus
resulting in an ID that's no longer a valid array index.

To fix this, use the position of the dai_link stored inside the PCM
runtime data relative to the start of the dai_link array as index into
the priv->dai_props array.

Signed-off-by: Laurentiu Mihalcea <laurentiu.mihalcea@xxxxxxx>
---
 include/sound/simple_card_utils.h     |  3 +++
 sound/soc/generic/simple-card-utils.c | 10 +++++-----
 2 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/include/sound/simple_card_utils.h b/include/sound/simple_card_utils.h
index 3360d9eab068..0122f7871a40 100644
--- a/include/sound/simple_card_utils.h
+++ b/include/sound/simple_card_utils.h
@@ -89,6 +89,9 @@ struct simple_util_priv {
 #define simple_props_to_dai_codec(props, i)	((props)->codec_dai + i)
 #define simple_props_to_codec_conf(props, i)	((props)->codec_conf + i)
 
+#define runtime_simple_priv_to_props(priv, rtd)					\
+	((priv)->dai_props + ((rtd)->dai_link - (priv)->dai_link))
+
 #define for_each_prop_dlc_cpus(props, i, cpu)				\
 	for ((i) = 0;							\
 	     ((i) < (props)->num.cpus) &&				\
diff --git a/sound/soc/generic/simple-card-utils.c b/sound/soc/generic/simple-card-utils.c
index a0c3111f7e08..c0f94e1cf0e9 100644
--- a/sound/soc/generic/simple-card-utils.c
+++ b/sound/soc/generic/simple-card-utils.c
@@ -296,7 +296,7 @@ int simple_util_startup(struct snd_pcm_substream *substream)
 {
 	struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);
 	struct simple_util_priv *priv = snd_soc_card_get_drvdata(rtd->card);
-	struct simple_dai_props *props = simple_priv_to_props(priv, rtd->id);
+	struct simple_dai_props *props = runtime_simple_priv_to_props(priv, rtd);
 	struct simple_util_dai *dai;
 	unsigned int fixed_sysclk = 0;
 	int i1, i2, i;
@@ -357,7 +357,7 @@ void simple_util_shutdown(struct snd_pcm_substream *substream)
 {
 	struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);
 	struct simple_util_priv *priv = snd_soc_card_get_drvdata(rtd->card);
-	struct simple_dai_props *props = simple_priv_to_props(priv, rtd->id);
+	struct simple_dai_props *props = runtime_simple_priv_to_props(priv, rtd);
 	struct simple_util_dai *dai;
 	int i;
 
@@ -446,7 +446,7 @@ int simple_util_hw_params(struct snd_pcm_substream *substream,
 	struct simple_util_dai *pdai;
 	struct snd_soc_dai *sdai;
 	struct simple_util_priv *priv = snd_soc_card_get_drvdata(rtd->card);
-	struct simple_dai_props *props = simple_priv_to_props(priv, rtd->id);
+	struct simple_dai_props *props = runtime_simple_priv_to_props(priv, rtd);
 	unsigned int mclk, mclk_fs = 0;
 	int i, ret;
 
@@ -517,7 +517,7 @@ int simple_util_be_hw_params_fixup(struct snd_soc_pcm_runtime *rtd,
 				   struct snd_pcm_hw_params *params)
 {
 	struct simple_util_priv *priv = snd_soc_card_get_drvdata(rtd->card);
-	struct simple_dai_props *dai_props = simple_priv_to_props(priv, rtd->id);
+	struct simple_dai_props *dai_props = runtime_simple_priv_to_props(priv, rtd);
 	struct simple_util_data *data = &dai_props->adata;
 	struct snd_interval *rate = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
 	struct snd_interval *channels = hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
@@ -628,7 +628,7 @@ static int simple_init_for_codec2codec(struct snd_soc_pcm_runtime *rtd,
 int simple_util_dai_init(struct snd_soc_pcm_runtime *rtd)
 {
 	struct simple_util_priv *priv = snd_soc_card_get_drvdata(rtd->card);
-	struct simple_dai_props *props = simple_priv_to_props(priv, rtd->id);
+	struct simple_dai_props *props = runtime_simple_priv_to_props(priv, rtd);
 	struct simple_util_dai *dai;
 	int i, ret;
 
-- 
2.34.1