[PATCH 1/2] ASoC: soc-core: copy the DAI link names into the card

[Tyler Baker <tyler.baker@oss.qualcomm.com>]

snd_soc_of_get_dai_link_codecs() and snd_soc_of_get_dai_link_cpus()
keep a DAI name owned by the component, which is freed when the
component unbinds, so the card cannot bind again afterwards.

Copy the name onto the card device, as simple-card and audio-graph-card
do since commit aa173b70d372 ("ASoC: generic: keep fallback dai_name
stable across rebind").

Fixes: e894efef9ac7 ("ASoC: core: add support to card rebind")
Fixes: 900dedd7e47c ("ASoC: Introduce snd_soc_of_get_dai_link_cpus")
Signed-off-by: Tyler Baker <tyler.baker@oss.qualcomm.com>
---
 sound/soc/soc-core.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c
index f33bece378b61..0e62965e35aaa 100644
--- a/sound/soc/soc-core.c
+++ b/sound/soc/soc-core.c
@@ -3253,6 +3253,18 @@ void snd_soc_of_put_dai_link_codecs(struct snd_soc_dai_link *dai_link)
 }
 EXPORT_SYMBOL_GPL(snd_soc_of_put_dai_link_codecs);
 
+/* dai_name belongs to the component, which can unbind before the card. */
+static int snd_soc_of_dup_dai_name(struct device *dev,
+				   struct snd_soc_dai_link_component *dlc)
+{
+	if (!dlc->dai_name)
+		return 0;
+
+	dlc->dai_name = devm_kstrdup_const(dev, dlc->dai_name, GFP_KERNEL);
+
+	return dlc->dai_name ? 0 : -ENOMEM;
+}
+
 /*
  * snd_soc_of_get_dai_link_codecs - Parse a list of CODECs in the devicetree
  * @dev: Card device
@@ -3282,6 +3294,8 @@ int snd_soc_of_get_dai_link_codecs(struct device *dev,
 	/* Parse the list */
 	for_each_link_codecs(dai_link, index, component) {
 		ret = snd_soc_of_get_dlc(of_node, NULL, component, index);
+		if (!ret)
+			ret = snd_soc_of_dup_dai_name(dev, component);
 		if (ret)
 			goto err;
 	}
@@ -3337,6 +3351,8 @@ int snd_soc_of_get_dai_link_cpus(struct device *dev,
 	/* Parse the list */
 	for_each_link_cpus(dai_link, index, component) {
 		ret = snd_soc_of_get_dlc(of_node, NULL, component, index);
+		if (!ret)
+			ret = snd_soc_of_dup_dai_name(dev, component);
 		if (ret)
 			goto err;
 	}
-- 
2.47.3