Add integer range getters to mixer

3 files changed, 47 insertions, 3 deletions

diff --git a/include/tinyalsa/asoundlib.h b/include/tinyalsa/asoundlib.h
index 4ee04a3..bd0cdee 100644
--- a/include/tinyalsa/asoundlib.h
+++ b/include/tinyalsa/asoundlib.h
@@ -131,4 +131,8 @@ int mixer_ctl_get_value(struct mixer_ctl *ctl, unsigned int id);
 int mixer_ctl_set_value(struct mixer_ctl *ctl, unsigned int id, int value);
 int mixer_ctl_set_enum_by_string(struct mixer_ctl *ctl, const char *string);
 
+/* Determe range of integer mixer controls */
+int mixer_ctl_get_range_min(struct mixer_ctl *ctl);
+int mixer_ctl_get_range_max(struct mixer_ctl *ctl);
+
 #endif
diff --git a/mixer.c b/mixer.c
index eedcbb7..2bb37a1 100644
--- a/mixer.c
+++ b/mixer.c
@@ -372,6 +372,40 @@ int mixer_ctl_set_value(struct mixer_ctl *ctl, unsigned int id, int value)
     return ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_WRITE, &ev);
 }
 
+int mixer_ctl_get_range_min(struct mixer_ctl *ctl)
+{
+    struct snd_ctl_elem_value ev;
+
+    if (!ctl || (ctl->info->type != SNDRV_CTL_ELEM_TYPE_INTEGER)) {
+        errno = EINVAL;
+        return -1;
+    }
+
+    memset(&ev, 0, sizeof(ev));
+    ev.id.numid = ctl->info->id.numid;
+    if (ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_READ, &ev))
+        return -1;
+
+    return ctl->info->value.integer.min;
+}
+
+int mixer_ctl_get_range_max(struct mixer_ctl *ctl)
+{
+    struct snd_ctl_elem_value ev;
+
+    if (!ctl || (ctl->info->type != SNDRV_CTL_ELEM_TYPE_INTEGER)) {
+        errno = EINVAL;
+        return -1;
+    }
+
+    memset(&ev, 0, sizeof(ev));
+    ev.id.numid = ctl->info->id.numid;
+    if (ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_READ, &ev))
+        return -1;
+
+    return ctl->info->value.integer.max;
+}
+
 unsigned int mixer_ctl_get_num_enums(struct mixer_ctl *ctl)
 {
     if (!ctl) {
diff --git a/tinymix.c b/tinymix.c
index 0b834cb..7f593b3 100644
--- a/tinymix.c
+++ b/tinymix.c
@@ -102,6 +102,7 @@ static void tinymix_detail_control(struct mixer *mixer, unsigned int id)
     unsigned int num_values;
     char buffer[256];
     unsigned int i;
+    int min, max;
 
     if (id >= mixer_get_num_ctls(mixer)) {
         fprintf(stderr, "Invalid mixer control\n");
@@ -119,19 +120,24 @@ static void tinymix_detail_control(struct mixer *mixer, unsigned int id)
         switch (type)
         {
         case MIXER_CTL_TYPE_INT:
-            printf("\t%d", mixer_ctl_get_value(ctl, i));
+            printf(" %d", mixer_ctl_get_value(ctl, i));
             break;
         case MIXER_CTL_TYPE_BOOL:
-            printf("\t%s", mixer_ctl_get_value(ctl, i) ? "On" : "Off");
+            printf(" %s", mixer_ctl_get_value(ctl, i) ? "On" : "Off");
             break;
         case MIXER_CTL_TYPE_ENUM:
             tinymix_print_enum(ctl);
             break;
         default:
-            printf("\tunknown");
+            printf(" unknown");
             break;
         };
     }
+    if (type == MIXER_CTL_TYPE_INT) {
+        min = mixer_ctl_get_range_min(ctl);
+        max = mixer_ctl_get_range_max(ctl);
+        printf(" (range %d->%d)", min, max);
+    }
     printf("\n");
 }