ALSA: core, oxygen, virtuoso: add an enum control info helper
Introduce the helper function snd_ctl_enum_info() to fill out the
elem_info fields for an enumerated control.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/core/control.c b/sound/core/control.c
index 45a8180..9ce00ed 100644
--- a/sound/core/control.c
+++ b/sound/core/control.c
@@ -1488,7 +1488,7 @@
}
/*
- * Frequently used control callbacks
+ * Frequently used control callbacks/helpers
*/
int snd_ctl_boolean_mono_info(struct snd_kcontrol *kcontrol,
struct snd_ctl_elem_info *uinfo)
@@ -1513,3 +1513,29 @@
}
EXPORT_SYMBOL(snd_ctl_boolean_stereo_info);
+
+/**
+ * snd_ctl_enum_info - fills the info structure for an enumerated control
+ * @info: the structure to be filled
+ * @channels: the number of the control's channels; often one
+ * @items: the number of control values; also the size of @names
+ * @names: an array containing the names of all control values
+ *
+ * Sets all required fields in @info to their appropriate values.
+ * If the control's accessibility is not the default (readable and writable),
+ * the caller has to fill @info->access.
+ */
+int snd_ctl_enum_info(struct snd_ctl_elem_info *info, unsigned int channels,
+ unsigned int items, const char *const names[])
+{
+ info->type = SNDRV_CTL_ELEM_TYPE_ENUMERATED;
+ info->count = channels;
+ info->value.enumerated.items = items;
+ if (info->value.enumerated.item >= items)
+ info->value.enumerated.item = items - 1;
+ strlcpy(info->value.enumerated.name,
+ names[info->value.enumerated.item],
+ sizeof(info->value.enumerated.name));
+ return 0;
+}
+EXPORT_SYMBOL(snd_ctl_enum_info);