mixer: add mixer_ctl_update() API

Some sound cards update their controls due to external
events, such as HDMI EDID byte data changing when an
HDMI cable is connected. This API allows the count of
elements to be updated.

1 files changed, 5 insertions, 0 deletions

diff --git a/mixer.c b/mixer.c
index 7419d3f..a413c60 100644
--- a/mixer.c
+++ b/mixer.c
@@ -195,6 +195,11 @@ struct mixer_ctl *mixer_get_ctl_by_name(struct mixer *mixer, const char *name)
     return NULL;
 }
 
+void mixer_ctl_update(struct mixer_ctl *ctl)
+{
+    ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_INFO, ctl->info);
+}
+
 const char *mixer_ctl_get_name(struct mixer_ctl *ctl)
 {
     if (!ctl)