diff --git a/sound/oss/dm.h b/sound/oss/dm.h
new file mode 100644
index 0000000..14a9059
--- /dev/null
+++ b/sound/oss/dm.h
@@ -0,0 +1,79 @@
+#ifndef _DRIVERS_SOUND_DM_H
+#define _DRIVERS_SOUND_DM_H
+
+/*
+ *	Definitions of the 'direct midi sound' interface used
+ *	by the newer commercial OSS package. We should export
+ *	this to userland somewhere in glibc later.
+ */
+
+/*
+ * Data structure composing an FM "note" or sound event.
+ */
+
+struct dm_fm_voice
+{
+	u8 op;
+	u8 voice;
+	u8 am;
+	u8 vibrato;
+	u8 do_sustain;
+	u8 kbd_scale;
+	u8 harmonic;
+	u8 scale_level;
+	u8 volume;
+	u8 attack;
+	u8 decay;
+	u8 sustain;
+	u8 release;
+	u8 feedback;
+	u8 connection;
+	u8 left;
+	u8 right;
+	u8 waveform;
+};
+
+/*
+ *	This describes an FM note by its voice, octave, frequency number (10bit)
+ *	and key on/off.
+ */
+
+struct dm_fm_note
+{
+	u8 voice;
+	u8 octave;
+	u32 fnum;
+	u8 key_on;
+};
+
+/*
+ * FM parameters that apply globally to all voices, and thus are not "notes"
+ */
+
+struct dm_fm_params
+{
+	u8 am_depth;
+	u8 vib_depth;
+	u8 kbd_split;
+	u8 rhythm;
+
+	/* This block is the percussion instrument data */
+	u8 bass;
+	u8 snare;
+	u8 tomtom;
+	u8 cymbal;
+	u8 hihat;
+};
+
+/*
+ *	FM mode ioctl settings
+ */
+ 
+#define FM_IOCTL_RESET        0x20
+#define FM_IOCTL_PLAY_NOTE    0x21
+#define FM_IOCTL_SET_VOICE    0x22
+#define FM_IOCTL_SET_PARAMS   0x23
+#define FM_IOCTL_SET_MODE     0x24
+#define FM_IOCTL_SET_OPL      0x25
+
+#endif