diff --git a/lib/debugfs/dev.h b/lib/debugfs/dev.h
new file mode 100644
index 0000000..c142651
--- /dev/null
+++ b/lib/debugfs/dev.h
@@ -0,0 +1,120 @@
+/*
+ * Copyright (c) 2019, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef DEV_H
+#define DEV_H
+
+#include <cdefs.h>
+#include <lib/debugfs.h>
+#include <stddef.h>
+
+/* FIXME: need configurability */
+#define NR_CHANS  10
+#define NR_CONSS  1
+#define NR_BINDS  4
+#define NR_FILES  18
+
+#define NODEV     255
+#define CHDIR     (1 << 15)
+
+#define SYNCDEV   0
+#define SYNCALL   1
+
+typedef struct dev dev_t;
+typedef struct chan chan_t;
+typedef struct dirtab dirtab_t;
+typedef int devgen_t(chan_t *, const dirtab_t *, int, int, dir_t *);
+typedef struct attr attr_t;
+
+enum {
+	DEV_ROOT_QROOT,
+	DEV_ROOT_QDEV,
+	DEV_ROOT_QFIP,
+	DEV_ROOT_QBLOBS,
+	DEV_ROOT_QBLOBCTL,
+	DEV_ROOT_QPSCI
+};
+
+/*******************************************************************************
+ * This structure contains the necessary information to represent a directory
+ * of the filesystem.
+ ******************************************************************************/
+struct dirtab {
+	char		name[NAMELEN];
+	qid_t		qid;
+	long		length;
+	unsigned char	perm;
+	void		*data;
+};
+
+/*******************************************************************************
+ * This structure defines the interface of device drivers.
+ * Each driver must implement a subset of those functions.
+ * It is possible to redirect to default implementations defined in dev.c.
+ ******************************************************************************/
+/* FIXME: comments for the callbacks */
+struct dev {
+	char id;
+	int (*stat)(chan_t *c, const char *file, dir_t *dir);
+	int (*walk)(chan_t *c, const char *name);
+	int (*read)(chan_t *c, void *buf, int n);
+	int (*write)(chan_t *c, void *buf, int n);
+	int (*seek)(chan_t *c, long off, int whence);
+	chan_t *(*clone)(chan_t *c, chan_t *nc);
+	chan_t *(*attach)(int id, int dev);
+	chan_t *(*mount)(chan_t *c, const char *spec);
+};
+
+/*******************************************************************************
+ * This structure defines the channel structure.
+ * A channel is a handle on an element of the filesystem.
+ ******************************************************************************/
+struct chan {
+	long		offset;
+	qid_t		qid;
+	unsigned char	index;	/* device index in devtab */
+	unsigned char	dev;
+	unsigned char	mode;
+};
+
+/*******************************************************************************
+ * This structure defines an abstract argument passed to physical drivers from
+ * the configuration file.
+ ******************************************************************************/
+struct attr {
+	char	*key;
+	char	*value;
+};
+
+chan_t *path_to_channel(const char *path, int mode);
+chan_t *clone(chan_t *c, chan_t *nc);
+chan_t *attach(int id, int dev);
+void channel_close(chan_t *c);
+int buf_to_channel(chan_t *c, void *dst, void *src, int nbytes, long len);
+int dirread(chan_t *c, dir_t *dir, const dirtab_t *tab,
+	    int ntab, devgen_t *gen);
+void make_dir_entry(chan_t *c, dir_t *dir, const char *name, long length,
+		    qid_t qid, unsigned int mode);
+void devlink(void);
+
+chan_t *devattach(int id, int dev);
+int devseek(chan_t *c, long off, int whence);
+chan_t *devclone(chan_t *c, chan_t *nc);
+int devgen(chan_t *c, const dirtab_t *tab, int ntab, int n, dir_t *dir);
+int devwalk(chan_t *c, const char *name, const dirtab_t *tab, int ntab,
+		   devgen_t *gen);
+int devstat(chan_t *dirc, const char *file, dir_t *dir,
+		   const dirtab_t *tab, int ntab, devgen_t *gen);
+
+chan_t *deverrmount(chan_t *c, const char *spec);
+int deverrwrite(chan_t *c, void *buf, int n);
+int deverrseek(chan_t *c, long off, int whence);
+
+extern dev_t *const devtab[];
+
+void __dead2 devpanic(const char *cause);
+
+#endif /* DEV_H */