1 files changed, 15 insertions, 0 deletions

diff --git a/include/sound/mpu401.h b/include/sound/mpu401.h
index d45218b44dfe..68b634b75068 100644
--- a/include/sound/mpu401.h
+++ b/include/sound/mpu401.h
@@ -103,6 +103,21 @@ struct snd_mpu401 {
 #define MPU401D(mpu) (mpu)->port
 
 /*
+ * control register bits
+ */
+/* read MPU401C() */
+#define MPU401_RX_EMPTY         0x80
+#define MPU401_TX_FULL          0x40
+
+/* write MPU401C() */
+#define MPU401_RESET            0xff
+#define MPU401_ENTER_UART       0x3f
+
+/* read MPU401D() */
+#define MPU401_ACK              0xfe
+
+
+/*
 
  */