diff --git a/ccid/ccid_device.c b/ccid/ccid_device.c
index 02d1599..b7077df 100644
--- a/ccid/ccid_device.c
+++ b/ccid/ccid_device.c
@@ -8,40 +8,7 @@
 #include <osmocom/core/utils.h>
 
 #include "ccid_proto.h"
-
-#define NR_SLOTS	8
-
-struct ccid_pars_decoded {
-	/* global for T0/T1 */
-	uint8_t fi;
-	uint8_t di;
-	enum ccid_clock_stop clock_stop;
-	bool inverse_convention;
-
-	struct {
-		uint8_t guard_time_etu;
-		uint8_t waiting_integer;
-	} t0;
-
-	struct {
-		enum ccid_t1_csum_type csum_type;
-		uint8_t guard_time_t1;
-		uint8_t bwi;
-		uint8_t cwi;
-		uint8_t ifsc;
-		uint8_t nad;
-	} t1;
-};
-
-struct ccid_slot {
-	struct ccid_instance *ci;
-	uint8_t slot_nr;
-	bool icc_present;
-	bool icc_powered;
-	bool icc_in_reset;
-	bool cmd_busy;
-	struct ccid_pars_decoded pars;
-};
+#include "ccid_device.h"
 
 /* decode on-the-wire T0 parameters into their parsed form */
 static int decode_ccid_pars_t0(struct ccid_pars_decoded *out, const struct ccid_proto_data_t0 *in)
@@ -134,23 +101,9 @@
 	out->bNadValue = in->t1.nad;
 }
 
-struct ccid_ops {
-	int (*send_in)(struct ccid_instance *ci, struct msgb *msg);
-};
-
-struct ccid_instance {
-	struct ccid_slot slot[NR_SLOTS];
-	struct ccid_ops ops;
-	const char *name;
-};
-
 #define msgb_ccid_out(x) (union ccid_pc_to_rdr *)msgb_data(x)
 #define msgb_ccid_in(x) (union ccid_rdr_to_pc *)msgb_data(x)
 
-#define LOGPCI(ci, lvl, fmt, args ...) LOGP(DCCID, lvl, "%s: " fmt, (ci)->name, ## args)
-#define LOGPCS(cs, lvl, fmt, args ...) \
-	LOGP(DCCID, lvl, "%s(%u): " fmt, (cc)->ci->name, (cc)->slot_nr, ## args)
-
 static struct ccid_slot *get_ccid_slot(struct ccid_instance *ci, uint8_t slot_nr)
 {
 	if (slot_nr >= sizeof(ci->slot))
diff --git a/ccid/ccid_device.h b/ccid/ccid_device.h
new file mode 100644
index 0000000..c7cef47
--- /dev/null
+++ b/ccid/ccid_device.h
@@ -0,0 +1,70 @@
+#pragma once
+#include <stdbool.h>
+#include <stdint.h>
+
+
+#define NR_SLOTS	8
+
+#define LOGPCI(ci, lvl, fmt, args ...) LOGP(DCCID, lvl, "%s: " fmt, (ci)->name, ## args)
+#define LOGPCS(cs, lvl, fmt, args ...) \
+	LOGP(DCCID, lvl, "%s(%u): " fmt, (cc)->ci->name, (cc)->slot_nr, ## args)
+
+struct msgb;
+
+struct ccid_pars_decoded {
+	/* global for T0/T1 */
+	uint8_t fi;
+	uint8_t di;
+	enum ccid_clock_stop clock_stop;
+	bool inverse_convention;
+
+	struct {
+		uint8_t guard_time_etu;
+		uint8_t waiting_integer;
+	} t0;
+
+	struct {
+		enum ccid_t1_csum_type csum_type;
+		uint8_t guard_time_t1;
+		uint8_t bwi;
+		uint8_t cwi;
+		uint8_t ifsc;
+		uint8_t nad;
+	} t1;
+};
+
+struct ccid_slot {
+	/* back-pointer to the ccid_instance */
+	struct ccid_instance *ci;
+	/* number of this slot (0 = first) */
+	uint8_t slot_nr;
+	/* is there an ICC physically present (card detect)? */
+	bool icc_present;
+	/* was there an ICC present during the last NotifSlotStatus?
+	 * should be set to zero every USB resume and setConfig != 0 */
+	bool icc_present_last;
+	/* is the ICC physically powered? */
+	bool icc_powered;
+	/* is the ICC currently in reset? */
+	bool icc_in_reset;
+	/* is this slot currently busy with processing a CCID command? */
+	bool cmd_busy;
+	/* decided CCID parameters */
+	struct ccid_pars_decoded pars;
+};
+
+/* CCID operations */
+struct ccid_ops {
+	int (*send_in)(struct ccid_instance *ci, struct msgb *msg);
+};
+
+/* An instance of CCID (i.e. a card reader device) */
+struct ccid_instance {
+	/* slots within the reader */
+	struct ccid_slot slot[NR_SLOTS];
+	/* set of function pointers implementing specific operations */
+	const struct ccid_ops ops;
+	const char *name;
+};
+
+int ccid_handle_out(struct ccid_instance *ci, struct msgb *msg);