[alsa-devel] [PATCH] ASoC: rt5677: Avoid recursive locking in the DEADLOCK detector

[Oder Chiou]

The patch is for to avoid recursive locking in the DEADLOCK detector.
In the driver, it encountered the warnning message of the recursive locking
in the function "regmap_lock_mutex".

Signed-off-by: Oder Chiou <oder_chiou at realtek.com>
---
 sound/soc/codecs/rt5677.c | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/sound/soc/codecs/rt5677.c b/sound/soc/codecs/rt5677.c
index 31d969a..ee5b570 100644
--- a/sound/soc/codecs/rt5677.c
+++ b/sound/soc/codecs/rt5677.c
@@ -4998,6 +4998,22 @@ static const struct regmap_config rt5677_regmap_physical = {
 	.num_ranges = ARRAY_SIZE(rt5677_ranges),
 };
 
+static void rt5677_regmap_lock_mutex(void *__lock)
+{
+	struct mutex *lock = __lock;
+
+	mutex_lock(lock);
+}
+
+static void rt5677_regmap_unlock_mutex(void *__lock)
+{
+	struct mutex *lock = __lock;
+
+	mutex_unlock(lock);
+}
+
+static struct mutex rt5677_regmap_lock;
+
 static const struct regmap_config rt5677_regmap = {
 	.reg_bits = 8,
 	.val_bits = 16,
@@ -5009,6 +5025,9 @@ static const struct regmap_config rt5677_regmap = {
 	.readable_reg = rt5677_readable_register,
 	.reg_read = rt5677_read,
 	.reg_write = rt5677_write,
+	.lock = rt5677_regmap_lock_mutex,
+	.unlock = rt5677_regmap_unlock_mutex,
+	.lock_arg = &rt5677_regmap_lock,
 
 	.cache_type = REGCACHE_RBTREE,
 	.reg_defaults = rt5677_reg,
@@ -5206,6 +5225,8 @@ static int rt5677_i2c_probe(struct i2c_client *i2c,
 		return ret;
 	}
 
+	mutex_init(&rt5677_regmap_lock);
+
 	regmap_read(rt5677->regmap, RT5677_VENDOR_ID2, &val);
 	if (val != RT5677_DEVICE_ID) {
 		dev_err(&i2c->dev,
-- 
1.9.1