@@ -275,6 +275,18 @@ int snd_hda_jack_detect_state_mst(struct
}
EXPORT_SYMBOL_GPL(snd_hda_jack_detect_state_mst);
+static bool func_is_already_in_callback_list(struct hda_jack_tbl *jack,
+ hda_jack_callback_fn func)
+{
+ struct hda_jack_callback *cb;
+
+ for (cb = jack->callback; cb; cb = cb->next) {
+ if (cb->func == func)
+ return true;
+ }
+ return false;
+}
+
/**
* snd_hda_jack_detect_enable_mst - enable the jack-detection
* @codec: the HDA codec
@@ -297,7 +309,7 @@ snd_hda_jack_detect_enable_callback_mst(
jack = snd_hda_jack_tbl_new(codec, nid, dev_id);
if (!jack)
return ERR_PTR(-ENOMEM);
- if (func) {
+ if (func && !func_is_already_in_callback_list(jack, func)) {
callback = kzalloc(sizeof(*callback), GFP_KERNEL);
if (!callback)
return ERR_PTR(-ENOMEM);