diff --git a/include/linux/mISDNdsp.h b/include/linux/mISDNdsp.h
new file mode 100644
index 0000000..6b71d2d
--- /dev/null
+++ b/include/linux/mISDNdsp.h
@@ -0,0 +1,37 @@
+#ifndef __mISDNdsp_H__
+#define __mISDNdsp_H__
+
+struct mISDN_dsp_element_arg {
+	char	*name;
+	char	*def;
+	char	*desc;
+};
+
+struct mISDN_dsp_element {
+	char	*name;
+	void	*(*new)(const char *arg);
+	void	(*free)(void *p);
+	void	(*process_tx)(void *p, unsigned char *data, int len);
+	void	(*process_rx)(void *p, unsigned char *data, int len);
+	int	num_args;
+	struct mISDN_dsp_element_arg
+		*args;
+};
+
+extern int  mISDN_dsp_element_register(struct mISDN_dsp_element *elem);
+extern void mISDN_dsp_element_unregister(struct mISDN_dsp_element *elem);
+
+struct dsp_features {
+	int	hfc_id; /* unique id to identify the chip (or -1) */
+	int	hfc_dtmf; /* set if HFCmulti card supports dtmf */
+	int	hfc_loops; /* set if card supports tone loops */
+	int	hfc_echocanhw; /* set if card supports echocancelation*/
+	int	pcm_id; /* unique id to identify the pcm bus (or -1) */
+	int	pcm_slots; /* number of slots on the pcm bus */
+	int	pcm_banks; /* number of IO banks of pcm bus */
+	int	unclocked; /* data is not clocked (has jitter/loss) */
+	int	unordered; /* data is unordered (packets have index) */
+};
+
+#endif
+