1 files changed, 17 insertions, 0 deletions

diff --git a/src/gba/gba.h b/src/gba/gba.h
index 74b6942..8ba3de5 100644
--- a/src/gba/gba.h
+++ b/src/gba/gba.h
@@ -524,6 +524,23 @@ sound_volume(SoundChannel channels, u8 volume, u8 pan) {
     return left | right;
 }
 
+inline u16 dmg_stereo_vol(u8 vol) {
+    return vol | (vol << 0x4);
+}
+
+inline u16
+channel_vol(SoundChannel channel, s8 pan) {
+    u16 left = (channel << 0xc);
+    u16 right = (channel << 0x8);
+    if (pan == -1) {
+        return left;
+    }
+    if (pan == +1) {
+        return right;
+    }
+    return left | right;
+}
+
 // Sound Direct Sound master bits.
 #define SOUND_DMG25           0x0
 #define SOUND_DMG50           0x1