Moved last libs, drivers and headers, cleaned up IO build

28 files changed, 3752 insertions, 0 deletions

diff --git a/src/drivers/device/cdev.cpp b/src/drivers/device/cdev.cpp
new file mode 100644
index 000000000..422321850
--- /dev/null
+++ b/src/drivers/device/cdev.cpp
@@ -0,0 +1,398 @@
+/****************************************************************************
+ *
+ *   Copyright (C) 2012 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file cdev.cpp
+ *
+ * Character device base class.
+ */
+
+#include "device.h"
+
+#include <sys/ioctl.h>
+#include <arch/irq.h>
+
+#include <stdlib.h>
+#include <stdio.h>
+
+#ifdef CONFIG_DISABLE_POLL
+# error This driver is not compatible with CONFIG_DISABLE_POLL
+#endif
+
+namespace device
+{
+
+/* how much to grow the poll waiter set each time it has to be increased */
+static const unsigned pollset_increment = 0;
+
+/*
+ * The standard NuttX operation dispatch table can't call C++ member functions
+ * directly, so we have to bounce them through this dispatch table.
+ */
+static int	cdev_open(struct file *filp);
+static int	cdev_close(struct file *filp);
+static ssize_t	cdev_read(struct file *filp, char *buffer, size_t buflen);
+static ssize_t	cdev_write(struct file *filp, const char *buffer, size_t buflen);
+static off_t	cdev_seek(struct file *filp, off_t offset, int whence);
+static int	cdev_ioctl(struct file *filp, int cmd, unsigned long arg);
+static int	cdev_poll(struct file *filp, struct pollfd *fds, bool setup);
+
+/**
+ * Character device indirection table.
+ *
+ * Every cdev we register gets the same function table; we use the private data
+ * field in the inode to store the instance pointer.
+ *
+ * Note that we use the GNU extension syntax here because we don't get designated
+ * initialisers in gcc 4.6.
+ */
+const struct file_operations CDev::fops = {
+open	: cdev_open,
+close	: cdev_close,
+read	: cdev_read,
+write	: cdev_write,
+seek	: cdev_seek,
+ioctl	: cdev_ioctl,
+poll	: cdev_poll,
+};
+
+CDev::CDev(const char *name,
+	   const char *devname,
+	   int irq) :
+	// base class
+	Device(name, irq),
+	// public
+	// protected
+	// private
+	_devname(devname),
+	_registered(false),
+	_open_count(0)
+{
+	for (unsigned i = 0; i < _max_pollwaiters; i++)
+		_pollset[i] = nullptr;
+}
+
+CDev::~CDev()
+{
+	if (_registered)
+		unregister_driver(_devname);
+}
+
+int
+CDev::init()
+{
+	int ret = OK;
+
+	// base class init first
+	ret = Device::init();
+
+	if (ret != OK)
+		goto out;
+
+	// now register the driver
+	ret = register_driver(_devname, &fops, 0666, (void *)this);
+
+	if (ret != OK)
+		goto out;
+
+	_registered = true;
+
+out:
+	return ret;
+}
+
+/*
+ * Default implementations of the character device interface
+ */
+int
+CDev::open(struct file *filp)
+{
+	int ret = OK;
+
+	lock();
+	/* increment the open count */
+	_open_count++;
+
+	if (_open_count == 1) {
+
+		/* first-open callback may decline the open */
+		ret = open_first(filp);
+
+		if (ret != OK)
+			_open_count--;
+	}
+
+	unlock();
+
+	return ret;
+}
+
+int
+CDev::open_first(struct file *filp)
+{
+	return OK;
+}
+
+int
+CDev::close(struct file *filp)
+{
+	int ret = OK;
+
+	lock();
+
+	if (_open_count > 0) {
+		/* decrement the open count */
+		_open_count--;
+
+		/* callback cannot decline the close */
+		if (_open_count == 0)
+			ret = close_last(filp);
+
+	} else {
+		ret = -EBADF;
+	}
+
+	unlock();
+
+	return ret;
+}
+
+int
+CDev::close_last(struct file *filp)
+{
+	return OK;
+}
+
+ssize_t
+CDev::read(struct file *filp, char *buffer, size_t buflen)
+{
+	return -ENOSYS;
+}
+
+ssize_t
+CDev::write(struct file *filp, const char *buffer, size_t buflen)
+{
+	return -ENOSYS;
+}
+
+off_t
+CDev::seek(struct file *filp, off_t offset, int whence)
+{
+	return -ENOSYS;
+}
+
+int
+CDev::ioctl(struct file *filp, int cmd, unsigned long arg)
+{
+	switch (cmd) {
+
+		/* fetch a pointer to the driver's private data */
+	case DIOC_GETPRIV:
+		*(void **)(uintptr_t)arg = (void *)this;
+		return OK;
+	}
+
+	return -ENOTTY;
+}
+
+int
+CDev::poll(struct file *filp, struct pollfd *fds, bool setup)
+{
+	int ret = OK;
+
+	/*
+	 * Lock against pollnotify() (and possibly other callers)
+	 */
+	lock();
+
+	if (setup) {
+		/*
+		 * Save the file pointer in the pollfd for the subclass'
+		 * benefit.
+		 */
+		fds->priv = (void *)filp;
+
+		/*
+		 * Handle setup requests.
+		 */
+		ret = store_poll_waiter(fds);
+
+		if (ret == OK) {
+
+			/*
+			 * Check to see whether we should send a poll notification
+			 * immediately.
+			 */
+			fds->revents |= fds->events & poll_state(filp);
+
+			/* yes? post the notification */
+			if (fds->revents != 0)
+				sem_post(fds->sem);
+		}
+
+	} else {
+		/*
+		 * Handle a teardown request.
+		 */
+		ret = remove_poll_waiter(fds);
+	}
+
+	unlock();
+
+	return ret;
+}
+
+void
+CDev::poll_notify(pollevent_t events)
+{
+	/* lock against poll() as well as other wakeups */
+	irqstate_t state = irqsave();
+
+	for (unsigned i = 0; i < _max_pollwaiters; i++)
+		if (nullptr != _pollset[i])
+			poll_notify_one(_pollset[i], events);
+
+	irqrestore(state);
+}
+
+void
+CDev::poll_notify_one(struct pollfd *fds, pollevent_t events)
+{
+	/* update the reported event set */
+	fds->revents |= fds->events & events;
+
+	/* if the state is now interesting, wake the waiter if it's still asleep */
+	/* XXX semcount check here is a vile hack; counting semphores should not be abused as cvars */
+	if ((fds->revents != 0) && (fds->sem->semcount <= 0))
+		sem_post(fds->sem);
+}
+
+pollevent_t
+CDev::poll_state(struct file *filp)
+{
+	/* by default, no poll events to report */
+	return 0;
+}
+
+int
+CDev::store_poll_waiter(struct pollfd *fds)
+{
+	/*
+	 * Look for a free slot.
+	 */
+	for (unsigned i = 0; i < _max_pollwaiters; i++) {
+		if (nullptr == _pollset[i]) {
+
+			/* save the pollfd */
+			_pollset[i] = fds;
+
+			return OK;
+		}
+	}
+
+	return ENOMEM;
+}
+
+int
+CDev::remove_poll_waiter(struct pollfd *fds)
+{
+	for (unsigned i = 0; i < _max_pollwaiters; i++) {
+		if (fds == _pollset[i]) {
+
+			_pollset[i] = nullptr;
+			return OK;
+
+		}
+	}
+
+	puts("poll: bad fd state");
+	return -EINVAL;
+}
+
+static int
+cdev_open(struct file *filp)
+{
+	CDev *cdev = (CDev *)(filp->f_inode->i_private);
+
+	return cdev->open(filp);
+}
+
+static int
+cdev_close(struct file *filp)
+{
+	CDev *cdev = (CDev *)(filp->f_inode->i_private);
+
+	return cdev->close(filp);
+}
+
+static ssize_t
+cdev_read(struct file *filp, char *buffer, size_t buflen)
+{
+	CDev *cdev = (CDev *)(filp->f_inode->i_private);
+
+	return cdev->read(filp, buffer, buflen);
+}
+
+static ssize_t
+cdev_write(struct file *filp, const char *buffer, size_t buflen)
+{
+	CDev *cdev = (CDev *)(filp->f_inode->i_private);
+
+	return cdev->write(filp, buffer, buflen);
+}
+
+static off_t
+cdev_seek(struct file *filp, off_t offset, int whence)
+{
+	CDev *cdev = (CDev *)(filp->f_inode->i_private);
+
+	return cdev->seek(filp, offset, whence);
+}
+
+static int
+cdev_ioctl(struct file *filp, int cmd, unsigned long arg)
+{
+	CDev *cdev = (CDev *)(filp->f_inode->i_private);
+
+	return cdev->ioctl(filp, cmd, arg);
+}
+
+static int
+cdev_poll(struct file *filp, struct pollfd *fds, bool setup)
+{
+	CDev *cdev = (CDev *)(filp->f_inode->i_private);
+
+	return cdev->poll(filp, fds, setup);
+}
+
+} // namespace device
\ No newline at end of file
diff --git a/src/drivers/device/device.cpp b/src/drivers/device/device.cpp
new file mode 100644
index 000000000..04a5222c3
--- /dev/null
+++ b/src/drivers/device/device.cpp
@@ -0,0 +1,227 @@
+/****************************************************************************
+ *
+ *   Copyright (C) 2012 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file device.cpp
+ *
+ * Fundamental driver base class for the device framework.
+ */
+
+#include "device.h"
+
+#include <nuttx/arch.h>
+#include <stdio.h>
+#include <unistd.h>
+
+namespace device
+{
+
+/**
+ * Interrupt dispatch table entry.
+ */
+struct irq_entry {
+	int	irq;
+	Device	*owner;
+};
+
+static const unsigned	irq_nentries = 8;		/**< size of the interrupt dispatch table */
+static irq_entry	irq_entries[irq_nentries];	/**< interrupt dispatch table (XXX should be a vector) */
+
+/**
+ * Register an interrupt to a specific device.
+ *
+ * @param irq		The interrupt number to register.
+ * @param owner		The device receiving the interrupt.
+ * @return		OK if the interrupt was registered.
+ */
+static int	register_interrupt(int irq, Device *owner);
+
+/**
+ * Unregister an interrupt.
+ *
+ * @param irq		The previously-registered interrupt to be de-registered.
+ */
+static void	unregister_interrupt(int irq);
+
+/**
+ * Handle an interrupt.
+ *
+ * @param irq		The interrupt being invoked.
+ * @param context	The interrupt register context.
+ * @return		Always returns OK.
+ */
+static int	interrupt(int irq, void *context);
+
+Device::Device(const char *name,
+	       int irq) :
+	// public
+	// protected
+	_name(name),
+	_debug_enabled(false),
+	// private
+	_irq(irq),
+	_irq_attached(false)
+{
+	sem_init(&_lock, 0, 1);
+}
+
+Device::~Device()
+{
+	sem_destroy(&_lock);
+
+	if (_irq_attached)
+		unregister_interrupt(_irq);
+}
+
+int
+Device::init()
+{
+	int ret = OK;
+
+	// If assigned an interrupt, connect it
+	if (_irq) {
+		/* ensure it's disabled */
+		up_disable_irq(_irq);
+
+		/* register */
+		ret = register_interrupt(_irq, this);
+
+		if (ret != OK)
+			goto out;
+
+		_irq_attached = true;
+	}
+
+out:
+	return ret;
+}
+
+void
+Device::interrupt_enable()
+{
+	if (_irq_attached)
+		up_enable_irq(_irq);
+}
+
+void
+Device::interrupt_disable()
+{
+	if (_irq_attached)
+		up_disable_irq(_irq);
+}
+
+void
+Device::interrupt(void *context)
+{
+	// default action is to disable the interrupt so we don't get called again
+	interrupt_disable();
+}
+
+void
+Device::log(const char *fmt, ...)
+{
+	va_list	ap;
+
+	printf("[%s] ", _name);
+	va_start(ap, fmt);
+	vprintf(fmt, ap);
+	va_end(ap);
+	printf("\n");
+	fflush(stdout);
+}
+
+void
+Device::debug(const char *fmt, ...)
+{
+	va_list	ap;
+
+	if (_debug_enabled) {
+		printf("<%s> ", _name);
+		va_start(ap, fmt);
+		vprintf(fmt, ap);
+		va_end(ap);
+		printf("\n");
+		fflush(stdout);
+	}
+}
+
+static int
+register_interrupt(int irq, Device *owner)
+{
+	int ret = -ENOMEM;
+
+	// look for a slot where we can register the interrupt
+	for (unsigned i = 0; i < irq_nentries; i++) {
+		if (irq_entries[i].irq == 0) {
+
+			// great, we could put it here; try attaching it
+			ret = irq_attach(irq, &interrupt);
+
+			if (ret == OK) {
+				irq_entries[i].irq = irq;
+				irq_entries[i].owner = owner;
+			}
+
+			break;
+		}
+	}
+
+	return ret;
+}
+
+static void
+unregister_interrupt(int irq)
+{
+	for (unsigned i = 0; i < irq_nentries; i++) {
+		if (irq_entries[i].irq == irq) {
+			irq_entries[i].irq = 0;
+			irq_entries[i].owner = nullptr;
+		}
+	}
+}
+
+static int
+interrupt(int irq, void *context)
+{
+	for (unsigned i = 0; i < irq_nentries; i++) {
+		if (irq_entries[i].irq == irq) {
+			irq_entries[i].owner->interrupt(context);
+			break;
+		}
+	}
+
+	return OK;
+}
+
+
+} // namespace device
\ No newline at end of file
diff --git a/src/drivers/device/device.h b/src/drivers/device/device.h
new file mode 100644
index 000000000..7d375aab9
--- /dev/null
+++ b/src/drivers/device/device.h
@@ -0,0 +1,447 @@
+/****************************************************************************
+ *
+ *   Copyright (C) 2012 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file device.h
+ *
+ * Definitions for the generic base classes in the device framework.
+ */
+
+#ifndef _DEVICE_DEVICE_H
+#define _DEVICE_DEVICE_H
+
+/*
+ * Includes here should only cover the needs of the framework definitions.
+ */
+#include <nuttx/config.h>
+
+#include <errno.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <poll.h>
+
+#include <nuttx/fs/fs.h>
+
+/**
+ * Namespace encapsulating all device framework classes, functions and data.
+ */
+namespace device __EXPORT
+{
+
+/**
+ * Fundamental base class for all device drivers.
+ *
+ * This class handles the basic "being a driver" things, including
+ * interrupt registration and dispatch.
+ */
+class __EXPORT Device
+{
+public:
+	/**
+	 * Interrupt handler.
+	 */
+	virtual void	interrupt(void *ctx);	/**< interrupt handler */
+
+protected:
+	const char	*_name;			/**< driver name */
+	bool		_debug_enabled;		/**< if true, debug messages are printed */
+
+	/**
+	 * Constructor
+	 *
+	 * @param name		Driver name
+	 * @param irq		Interrupt assigned to the device.
+	 */
+	Device(const char *name,
+	       int irq = 0);
+	~Device();
+
+	/**
+	 * Initialise the driver and make it ready for use.
+	 *
+	 * @return	OK if the driver initialised OK.
+	 */
+	virtual int	init();
+
+	/**
+	 * Enable the device interrupt
+	 */
+	void		interrupt_enable();
+
+	/**
+	 * Disable the device interrupt
+	 */
+	void		interrupt_disable();
+
+	/**
+	 * Take the driver lock.
+	 *
+	 * Each driver instance has its own lock/semaphore.
+	 *
+	 * Note that we must loop as the wait may be interrupted by a signal.
+	 */
+	void		lock() {
+		do {} while (sem_wait(&_lock) != 0);
+	}
+
+	/**
+	 * Release the driver lock.
+	 */
+	void		unlock() {
+		sem_post(&_lock);
+	}
+
+	/**
+	 * Log a message.
+	 *
+	 * The message is prefixed with the driver name, and followed
+	 * by a newline.
+	 */
+	void		log(const char *fmt, ...);
+
+	/**
+	 * Print a debug message.
+	 *
+	 * The message is prefixed with the driver name, and followed
+	 * by a newline.
+	 */
+	void		debug(const char *fmt, ...);
+
+private:
+	int		_irq;
+	bool		_irq_attached;
+	sem_t		_lock;
+
+	/** disable copy construction for this and all subclasses */
+	Device(const Device &);
+
+	/** disable assignment for this and all subclasses */
+	Device &operator = (const Device &);
+
+	/**
+	 * Register ourselves as a handler for an interrupt
+	 *
+	 * @param irq		The interrupt to claim
+	 * @return		OK if the interrupt was registered
+	 */
+	int		dev_register_interrupt(int irq);
+
+	/**
+	 * Unregister ourselves as a handler for any interrupt
+	 */
+	void		dev_unregister_interrupt();
+
+	/**
+	 * Interrupt dispatcher
+	 *
+	 * @param irq		The interrupt that has been triggered.
+	 * @param context	Pointer to the interrupted context.
+	 */
+	static void	dev_interrupt(int irq, void *context);
+};
+
+/**
+ * Abstract class for any character device
+ */
+class __EXPORT CDev : public Device
+{
+public:
+	/**
+	 * Constructor
+	 *
+	 * @param name		Driver name
+	 * @param devname	Device node name
+	 * @param irq		Interrupt assigned to the device
+	 */
+	CDev(const char *name, const char *devname, int irq = 0);
+
+	/**
+	 * Destructor
+	 */
+	~CDev();
+
+	virtual int	init();
+
+	/**
+	 * Handle an open of the device.
+	 *
+	 * This function is called for every open of the device. The default
+	 * implementation maintains _open_count and always returns OK.
+	 *
+	 * @param filp		Pointer to the NuttX file structure.
+	 * @return		OK if the open is allowed, -errno otherwise.
+	 */
+	virtual int	open(struct file *filp);
+
+	/**
+	 * Handle a close of the device.
+	 *
+	 * This function is called for every close of the device. The default
+	 * implementation maintains _open_count and returns OK as long as it is not zero.
+	 *
+	 * @param filp		Pointer to the NuttX file structure.
+	 * @return		OK if the close was successful, -errno otherwise.
+	 */
+	virtual int	close(struct file *filp);
+
+	/**
+	 * Perform a read from the device.
+	 *
+	 * The default implementation returns -ENOSYS.
+	 *
+	 * @param filp		Pointer to the NuttX file structure.
+	 * @param buffer	Pointer to the buffer into which data should be placed.
+	 * @param buflen	The number of bytes to be read.
+	 * @return		The number of bytes read or -errno otherwise.
+	 */
+	virtual ssize_t	read(struct file *filp, char *buffer, size_t buflen);
+
+	/**
+	 * Perform a write to the device.
+	 *
+	 * The default implementation returns -ENOSYS.
+	 *
+	 * @param filp		Pointer to the NuttX file structure.
+	 * @param buffer	Pointer to the buffer from which data should be read.
+	 * @param buflen	The number of bytes to be written.
+	 * @return		The number of bytes written or -errno otherwise.
+	 */
+	virtual ssize_t	write(struct file *filp, const char *buffer, size_t buflen);
+
+	/**
+	 * Perform a logical seek operation on the device.
+	 *
+	 * The default implementation returns -ENOSYS.
+	 *
+	 * @param filp		Pointer to the NuttX file structure.
+	 * @param offset	The new file position relative to whence.
+	 * @param whence	SEEK_OFS, SEEK_CUR or SEEK_END.
+	 * @return		The previous offset, or -errno otherwise.
+	 */
+	virtual off_t	seek(struct file *filp, off_t offset, int whence);
+
+	/**
+	 * Perform an ioctl operation on the device.
+	 *
+	 * The default implementation handles DIOC_GETPRIV, and otherwise
+	 * returns -ENOTTY. Subclasses should call the default implementation
+	 * for any command they do not handle themselves.
+	 *
+	 * @param filp		Pointer to the NuttX file structure.
+	 * @param cmd		The ioctl command value.
+	 * @param arg		The ioctl argument value.
+	 * @return		OK on success, or -errno otherwise.
+	 */
+	virtual int	ioctl(struct file *filp, int cmd, unsigned long arg);
+
+	/**
+	 * Perform a poll setup/teardown operation.
+	 *
+	 * This is handled internally and should not normally be overridden.
+	 *
+	 * @param filp		Pointer to the NuttX file structure.
+	 * @param fds		Poll descriptor being waited on.
+	 * @param arg		True if this is establishing a request, false if
+	 *			it is being torn down.
+	 * @return		OK on success, or -errno otherwise.
+	 */
+	virtual int	poll(struct file *filp, struct pollfd *fds, bool setup);
+
+	/**
+	 * Test whether the device is currently open.
+	 *
+	 * This can be used to avoid tearing down a device that is still active.
+	 *
+	 * @return              True if the device is currently open.
+	 */
+	bool            is_open() { return _open_count > 0; }
+
+protected:
+	/**
+	 * Pointer to the default cdev file operations table; useful for
+	 * registering clone devices etc.
+	 */
+	static const struct file_operations	fops;
+
+	/**
+	 * Check the current state of the device for poll events from the
+	 * perspective of the file.
+	 *
+	 * This function is called by the default poll() implementation when
+	 * a poll is set up to determine whether the poll should return immediately.
+	 *
+	 * The default implementation returns no events.
+	 *
+	 * @param filp		The file that's interested.
+	 * @return		The current set of poll events.
+	 */
+	virtual pollevent_t poll_state(struct file *filp);
+
+	/**
+	 * Report new poll events.
+	 *
+	 * This function should be called anytime the state of the device changes
+	 * in a fashion that might be interesting to a poll waiter.
+	 *
+	 * @param events	The new event(s) being announced.
+	 */
+	virtual void	poll_notify(pollevent_t events);
+
+	/**
+	 * Internal implementation of poll_notify.
+	 *
+	 * @param fds		A poll waiter to notify.
+	 * @param events	The event(s) to send to the waiter.
+	 */
+	virtual void	poll_notify_one(struct pollfd *fds, pollevent_t events);
+
+	/**
+	 * Notification of the first open.
+	 *
+	 * This function is called when the device open count transitions from zero
+	 * to one.  The driver lock is held for the duration of the call.
+	 *
+	 * The default implementation returns OK.
+	 *
+	 * @param filp		Pointer to the NuttX file structure.
+	 * @return		OK if the open should proceed, -errno otherwise.
+	 */
+	virtual int	open_first(struct file *filp);
+
+	/**
+	 * Notification of the last close.
+	 *
+	 * This function is called when the device open count transitions from
+	 * one to zero.  The driver lock is held for the duration of the call.
+	 *
+	 * The default implementation returns OK.
+	 *
+	 * @param filp		Pointer to the NuttX file structure.
+	 * @return		OK if the open should return OK, -errno otherwise.
+	 */
+	virtual int	close_last(struct file *filp);
+
+private:
+	static const unsigned _max_pollwaiters = 8;
+
+	const char	*_devname;		/**< device node name */
+	bool		_registered;		/**< true if device name was registered */
+	unsigned	_open_count;		/**< number of successful opens */
+
+	struct pollfd	*_pollset[_max_pollwaiters];
+
+	/**
+	 * Store a pollwaiter in a slot where we can find it later.
+	 *
+	 * Expands the pollset as required.  Must be called with the driver locked.
+	 *
+	 * @return		OK, or -errno on error.
+	 */
+	int		store_poll_waiter(struct pollfd *fds);
+
+	/**
+	 * Remove a poll waiter.
+	 *
+	 * @return		OK, or -errno on error.
+	 */
+	int		remove_poll_waiter(struct pollfd *fds);
+};
+
+/**
+ * Abstract class for character device accessed via PIO
+ */
+class __EXPORT PIO : public CDev
+{
+public:
+	/**
+	 * Constructor
+	 *
+	 * @param name		Driver name
+	 * @param devname	Device node name
+	 * @param base		Base address of the device PIO area
+	 * @param irq		Interrupt assigned to the device (or zero if none)
+	 */
+	PIO(const char *name,
+	    const char *devname,
+	    uint32_t base,
+	    int irq = 0);
+	~PIO();
+
+	int		init();
+
+protected:
+
+	/**
+	 * Read a register
+	 *
+	 * @param offset	Register offset in bytes from the base address.
+	 */
+	uint32_t reg(uint32_t offset) {
+		return *(volatile uint32_t *)(_base + offset);
+	}
+
+	/**
+	 * Write a register
+	 *
+	 * @param offset	Register offset in bytes from the base address.
+	 * @param value	Value to write.
+	 */
+	void		reg(uint32_t offset, uint32_t value) {
+		*(volatile uint32_t *)(_base + offset) = value;
+	}
+
+	/**
+	 * Modify a register
+	 *
+	 * Note that there is a risk of a race during the read/modify/write cycle
+	 * that must be taken care of by the caller.
+	 *
+	 * @param offset	Register offset in bytes from the base address.
+	 * @param clearbits	Bits to clear in the register
+	 * @param setbits	Bits to set in the register
+	 */
+	void		modify(uint32_t offset, uint32_t clearbits, uint32_t setbits) {
+		uint32_t val = reg(offset);
+		val &= ~clearbits;
+		val |= setbits;
+		reg(offset, val);
+	}
+
+private:
+	uint32_t	_base;
+};
+
+} // namespace device
+
+#endif /* _DEVICE_DEVICE_H */
\ No newline at end of file
diff --git a/src/drivers/device/i2c.cpp b/src/drivers/device/i2c.cpp
new file mode 100644
index 000000000..a416801eb
--- /dev/null
+++ b/src/drivers/device/i2c.cpp
@@ -0,0 +1,204 @@
+/****************************************************************************
+ *
+ *   Copyright (C) 2012 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file i2c.cpp
+ *
+ * Base class for devices attached via the I2C bus.
+ *
+ * @todo Bus frequency changes; currently we do nothing with the value
+ *       that is supplied.  Should we just depend on the bus knowing?
+ */
+
+#include "i2c.h"
+
+namespace device
+{
+
+I2C::I2C(const char *name,
+	 const char *devname,
+	 int bus,
+	 uint16_t address,
+	 uint32_t frequency,
+	 int irq) :
+	// base class
+	CDev(name, devname, irq),
+	// public
+	// protected
+	_retries(0),
+	// private
+	_bus(bus),
+	_address(address),
+	_frequency(frequency),
+	_dev(nullptr)
+{
+}
+
+I2C::~I2C()
+{
+	if (_dev)
+		up_i2cuninitialize(_dev);
+}
+
+int
+I2C::init()
+{
+	int ret = OK;
+
+	/* attach to the i2c bus */
+	_dev = up_i2cinitialize(_bus);
+
+	if (_dev == nullptr) {
+		debug("failed to init I2C");
+		ret = -ENOENT;
+		goto out;
+	}
+
+	// call the probe function to check whether the device is present
+	ret = probe();
+
+	if (ret != OK) {
+		debug("probe failed");
+		goto out;
+	}
+
+	// do base class init, which will create device node, etc
+	ret = CDev::init();
+
+	if (ret != OK) {
+		debug("cdev init failed");
+		goto out;
+	}
+
+	// tell the world where we are
+	log("on I2C bus %d at 0x%02x", _bus, _address);
+
+out:
+	return ret;
+}
+
+int
+I2C::probe()
+{
+	// Assume the device is too stupid to be discoverable.
+	return OK;
+}
+
+int
+I2C::transfer(const uint8_t *send, unsigned send_len, uint8_t *recv, unsigned recv_len)
+{
+	struct i2c_msg_s msgv[2];
+	unsigned msgs;
+	int ret;
+	unsigned retry_count = 0;
+
+	do {
+		//	debug("transfer out %p/%u  in %p/%u", send, send_len, recv, recv_len);
+
+		msgs = 0;
+
+		if (send_len > 0) {
+			msgv[msgs].addr = _address;
+			msgv[msgs].flags = 0;
+			msgv[msgs].buffer = const_cast<uint8_t *>(send);
+			msgv[msgs].length = send_len;
+			msgs++;
+		}
+
+		if (recv_len > 0) {
+			msgv[msgs].addr = _address;
+			msgv[msgs].flags = I2C_M_READ;
+			msgv[msgs].buffer = recv;
+			msgv[msgs].length = recv_len;
+			msgs++;
+		}
+
+		if (msgs == 0)
+			return -EINVAL;
+
+		/*
+		 * I2C architecture means there is an unavoidable race here
+		 * if there are any devices on the bus with a different frequency
+		 * preference.  Really, this is pointless.
+		 */
+		I2C_SETFREQUENCY(_dev, _frequency);
+		ret = I2C_TRANSFER(_dev, &msgv[0], msgs);
+
+		/* success */
+		if (ret == OK)
+			break;
+
+		/* if we have already retried once, or we are going to give up, then reset the bus */
+		if ((retry_count >= 1) || (retry_count >= _retries))
+			up_i2creset(_dev);
+
+	} while (retry_count++ < _retries);
+
+	return ret;
+
+}
+
+int
+I2C::transfer(i2c_msg_s *msgv, unsigned msgs)
+{
+	int ret;
+	unsigned retry_count = 0;
+
+	/* force the device address into the message vector */
+	for (unsigned i = 0; i < msgs; i++)
+		msgv[i].addr = _address;
+
+
+	do {
+		/*
+		 * I2C architecture means there is an unavoidable race here
+		 * if there are any devices on the bus with a different frequency
+		 * preference.  Really, this is pointless.
+		 */
+		I2C_SETFREQUENCY(_dev, _frequency);
+		ret = I2C_TRANSFER(_dev, msgv, msgs);
+
+		/* success */
+		if (ret == OK)
+			break;
+
+		/* if we have already retried once, or we are going to give up, then reset the bus */
+		if ((retry_count >= 1) || (retry_count >= _retries))
+			up_i2creset(_dev);
+
+	} while (retry_count++ < _retries);
+
+	return ret;
+}
+
+} // namespace device
\ No newline at end of file
diff --git a/src/drivers/device/i2c.h b/src/drivers/device/i2c.h
new file mode 100644
index 000000000..7daba31be
--- /dev/null
+++ b/src/drivers/device/i2c.h
@@ -0,0 +1,138 @@
+/****************************************************************************
+ *
+ *   Copyright (C) 2012 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file i2c.h
+ *
+ * Base class for devices connected via I2C.
+ */
+
+#ifndef _DEVICE_I2C_H
+#define _DEVICE_I2C_H
+
+#include "device.h"
+
+#include <nuttx/i2c.h>
+
+namespace device __EXPORT
+{
+
+/**
+ * Abstract class for character device on I2C
+ */
+class __EXPORT I2C : public CDev
+{
+
+protected:
+	/**
+	 * The number of times a read or write operation will be retried on
+	 * error.
+	 */
+	unsigned		_retries;
+
+	/**
+	 * The I2C bus number the device is attached to.
+	 */
+	int			_bus;
+
+	/**
+	 * @ Constructor
+	 *
+	 * @param name		Driver name
+	 * @param devname	Device node name
+	 * @param bus		I2C bus on which the device lives
+	 * @param address	I2C bus address, or zero if set_address will be used
+	 * @param frequency	I2C bus frequency for the device (currently not used)
+	 * @param irq		Interrupt assigned to the device (or zero if none)
+	 */
+	I2C(const char *name,
+	    const char *devname,
+	    int bus,
+	    uint16_t address,
+	    uint32_t frequency,
+	    int irq = 0);
+	~I2C();
+
+	virtual int	init();
+
+	/**
+	 * Check for the presence of the device on the bus.
+	 */
+	virtual int	probe();
+
+	/**
+	 * Perform an I2C transaction to the device.
+	 *
+	 * At least one of send_len and recv_len must be non-zero.
+	 *
+	 * @param send		Pointer to bytes to send.
+	 * @param send_len	Number of bytes to send.
+	 * @param recv		Pointer to buffer for bytes received.
+	 * @param recv_len	Number of bytes to receive.
+	 * @return		OK if the transfer was successful, -errno
+	 *			otherwise.
+	 */
+	int		transfer(const uint8_t *send, unsigned send_len,
+				 uint8_t *recv, unsigned recv_len);
+
+	/**
+	 * Perform a multi-part I2C transaction to the device.
+	 *
+	 * @param msgv		An I2C message vector.
+	 * @param msgs		The number of entries in the message vector.
+	 * @return		OK if the transfer was successful, -errno
+	 *			otherwise.
+	 */
+	int		transfer(i2c_msg_s *msgv, unsigned msgs);
+
+	/**
+	 * Change the bus address.
+	 *
+	 * Most often useful during probe() when the driver is testing
+	 * several possible bus addresses.
+	 *
+	 * @param address	The new bus address to set.
+	 */
+	void		set_address(uint16_t address) {
+		_address = address;
+	}
+
+private:
+	uint16_t		_address;
+	uint32_t		_frequency;
+	struct i2c_dev_s	*_dev;
+};
+
+} // namespace device
+
+#endif /* _DEVICE_I2C_H */
diff --git a/src/drivers/device/module.mk b/src/drivers/device/module.mk
new file mode 100644
index 000000000..8c716d9cd
--- /dev/null
+++ b/src/drivers/device/module.mk
@@ -0,0 +1,42 @@
+############################################################################
+#
+#   Copyright (c) 2012, 2013 PX4 Development Team. All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+#
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in
+#    the documentation and/or other materials provided with the
+#    distribution.
+# 3. Neither the name PX4 nor the names of its contributors may be
+#    used to endorse or promote products derived from this software
+#    without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+# FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+# COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+# BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+# OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+# AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+# ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+# POSSIBILITY OF SUCH DAMAGE.
+#
+############################################################################
+
+#
+# Build the device driver framework.
+#
+
+SRCS		= cdev.cpp \
+		  device.cpp \
+		  i2c.cpp \
+		  pio.cpp \
+		  spi.cpp
diff --git a/src/drivers/device/pio.cpp b/src/drivers/device/pio.cpp
new file mode 100644
index 000000000..f3a805a5e
--- /dev/null
+++ b/src/drivers/device/pio.cpp
@@ -0,0 +1,74 @@
+/****************************************************************************
+ *
+ *   Copyright (C) 2012 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file pio.cpp
+ *
+ * Base class for devices accessed via PIO to registers.
+ */
+
+#include "device.h"
+
+namespace device
+{
+
+PIO::PIO(const char *name,
+	 const char *devname,
+	 uint32_t base,
+	 int irq) :
+	// base class
+	CDev(name, devname, irq),
+	// public
+	// protected
+	// private
+	_base(base)
+{
+}
+
+PIO::~PIO()
+{
+	// nothing to do here...
+}
+
+int
+PIO::init()
+{
+	int ret = OK;
+
+	// base class init first
+	ret = CDev::init();
+
+	return ret;
+}
+
+} // namespace device
\ No newline at end of file
diff --git a/src/drivers/device/spi.cpp b/src/drivers/device/spi.cpp
new file mode 100644
index 000000000..8fffd60cb
--- /dev/null
+++ b/src/drivers/device/spi.cpp
@@ -0,0 +1,160 @@
+/****************************************************************************
+ *
+ *   Copyright (C) 2012 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file spi.cpp
+ *
+ * Base class for devices connected via SPI.
+ *
+ * @todo Work out if caching the mode/frequency would save any time.
+ *
+ * @todo A separate bus/device abstraction would allow for mixed interrupt-mode
+ * and non-interrupt-mode clients to arbitrate for the bus.  As things stand,
+ * a bus shared between clients of both kinds is vulnerable to races between
+ * the two, where an interrupt-mode client will ignore the lock held by the
+ * non-interrupt-mode client.
+ */
+
+#include <nuttx/arch.h>
+
+#include "spi.h"
+
+#ifndef CONFIG_SPI_EXCHANGE
+# error This driver requires CONFIG_SPI_EXCHANGE
+#endif
+
+namespace device
+{
+
+SPI::SPI(const char *name,
+	 const char *devname,
+	 int bus,
+	 enum spi_dev_e device,
+	 enum spi_mode_e mode,
+	 uint32_t frequency,
+	 int irq) :
+	// base class
+	CDev(name, devname, irq),
+	// public
+	// protected
+	// private
+	_bus(bus),
+	_device(device),
+	_mode(mode),
+	_frequency(frequency),
+	_dev(nullptr)
+{
+}
+
+SPI::~SPI()
+{
+	// XXX no way to let go of the bus...
+}
+
+int
+SPI::init()
+{
+	int ret = OK;
+
+	/* attach to the spi bus */
+	if (_dev == nullptr)
+		_dev = up_spiinitialize(_bus);
+
+	if (_dev == nullptr) {
+		debug("failed to init SPI");
+		ret = -ENOENT;
+		goto out;
+	}
+
+	/* deselect device to ensure high to low transition of pin select */
+	SPI_SELECT(_dev, _device, false);
+
+	/* call the probe function to check whether the device is present */
+	ret = probe();
+
+	if (ret != OK) {
+		debug("probe failed");
+		goto out;
+	}
+
+	/* do base class init, which will create the device node, etc. */
+	ret = CDev::init();
+
+	if (ret != OK) {
+		debug("cdev init failed");
+		goto out;
+	}
+
+	/* tell the workd where we are */
+	log("on SPI bus %d at %d", _bus, _device);
+
+out:
+	return ret;
+}
+
+int
+SPI::probe()
+{
+	// assume the device is too stupid to be discoverable
+	return OK;
+}
+
+int
+SPI::transfer(uint8_t *send, uint8_t *recv, unsigned len)
+{
+
+	if ((send == nullptr) && (recv == nullptr))
+		return -EINVAL;
+
+	/* do common setup */
+	if (!up_interrupt_context())
+		SPI_LOCK(_dev, true);
+
+	SPI_SETFREQUENCY(_dev, _frequency);
+	SPI_SETMODE(_dev, _mode);
+	SPI_SETBITS(_dev, 8);
+	SPI_SELECT(_dev, _device, true);
+
+	/* do the transfer */
+	SPI_EXCHANGE(_dev, send, recv, len);
+
+	/* and clean up */
+	SPI_SELECT(_dev, _device, false);
+
+	if (!up_interrupt_context())
+		SPI_LOCK(_dev, false);
+
+	return OK;
+}
+
+} // namespace device
diff --git a/src/drivers/device/spi.h b/src/drivers/device/spi.h
new file mode 100644
index 000000000..d2d01efb3
--- /dev/null
+++ b/src/drivers/device/spi.h
@@ -0,0 +1,114 @@
+/****************************************************************************
+ *
+ *   Copyright (C) 2012 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file spi.h
+ *
+ * Base class for devices connected via SPI.
+ */
+
+#ifndef _DEVICE_SPI_H
+#define _DEVICE_SPI_H
+
+#include "device.h"
+
+#include <nuttx/spi.h>
+
+namespace device __EXPORT
+{
+
+/**
+ * Abstract class for character device on SPI
+ */
+class __EXPORT SPI : public CDev
+{
+protected:
+	/**
+	 * Constructor
+	 *
+	 * @param name		Driver name
+	 * @param devname	Device node name
+	 * @param bus		SPI bus on which the device lives
+	 * @param device	Device handle (used by SPI_SELECT)
+	 * @param mode		SPI clock/data mode
+	 * @param frequency	SPI clock frequency
+	 * @param irq		Interrupt assigned to the device (or zero if none)
+	 */
+	SPI(const char *name,
+	    const char *devname,
+	    int bus,
+	    enum spi_dev_e device,
+	    enum spi_mode_e mode,
+	    uint32_t frequency,
+	    int irq = 0);
+	~SPI();
+
+	virtual int	init();
+
+	/**
+	 * Check for the presence of the device on the bus.
+	 */
+	virtual int	probe();
+
+	/**
+	 * Perform a SPI transfer.
+	 *
+	 * If called from interrupt context, this interface does not lock
+	 * the bus and may interfere with non-interrupt-context callers.
+	 *
+	 * Clients in a mixed interrupt/non-interrupt configuration must
+	 * ensure appropriate interlocking.
+	 *
+	 * At least one of send or recv must be non-null.
+	 *
+	 * @param send		Bytes to send to the device, or nullptr if
+	 *			no data is to be sent.
+	 * @param recv		Buffer for receiving bytes from the device,
+	 *			or nullptr if no bytes are to be received.
+	 * @param len		Number of bytes to transfer.
+	 * @return		OK if the exchange was successful, -errno
+	 *			otherwise.
+	 */
+	int		transfer(uint8_t *send, uint8_t *recv, unsigned len);
+
+private:
+	int			_bus;
+	enum spi_dev_e		_device;
+	enum spi_mode_e		_mode;
+	uint32_t		_frequency;
+	struct spi_dev_s	*_dev;
+};
+
+} // namespace device
+
+#endif /* _DEVICE_SPI_H */
diff --git a/src/drivers/drv_accel.h b/src/drivers/drv_accel.h
new file mode 100644
index 000000000..794de584b
--- /dev/null
+++ b/src/drivers/drv_accel.h
@@ -0,0 +1,121 @@
+/****************************************************************************
+ *
+ *   Copyright (C) 2012 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file Accelerometer driver interface.
+ */
+
+#ifndef _DRV_ACCEL_H
+#define _DRV_ACCEL_H
+
+#include <stdint.h>
+#include <sys/ioctl.h>
+
+#include "drv_sensor.h"
+#include "drv_orb_dev.h"
+
+#define ACCEL_DEVICE_PATH	"/dev/accel"
+
+/**
+ * accel report structure.  Reads from the device must be in multiples of this
+ * structure.
+ */
+struct accel_report {
+	uint64_t timestamp;
+	float x;		/**< acceleration in the NED X board axis in m/s^2 */
+	float y;		/**< acceleration in the NED Y board axis in m/s^2 */
+	float z;		/**< acceleration in the NED Z board axis in m/s^2 */
+	float temperature;	/**< temperature in degrees celsius */
+	float range_m_s2;	/**< range in m/s^2 (+- this value) */
+	float scaling;
+
+	int16_t x_raw;
+	int16_t y_raw;
+	int16_t z_raw;
+	int16_t temperature_raw;
+};
+
+/** accel scaling factors; Vout = (Vin * Vscale) + Voffset */
+struct accel_scale {
+	float	x_offset;
+	float	x_scale;
+	float	y_offset;
+	float	y_scale;
+	float	z_offset;
+	float	z_scale;
+};
+
+/*
+ * ObjDev tag for raw accelerometer data.
+ */
+ORB_DECLARE(sensor_accel);
+
+/*
+ * ioctl() definitions
+ *
+ * Accelerometer drivers also implement the generic sensor driver
+ * interfaces from drv_sensor.h
+ */
+
+#define _ACCELIOCBASE		(0x2100)
+#define _ACCELIOC(_n)		(_IOC(_ACCELIOCBASE, _n))
+
+
+/** set the accel internal sample rate to at least (arg) Hz */
+#define ACCELIOCSSAMPLERATE	_ACCELIOC(0)
+
+/** return the accel internal sample rate in Hz */
+#define ACCELIOCGSAMPLERATE	_ACCELIOC(1)
+
+/** set the accel internal lowpass filter to no lower than (arg) Hz */
+#define ACCELIOCSLOWPASS	_ACCELIOC(2)
+
+/** return the accel internal lowpass filter in Hz */
+#define ACCELIOCGLOWPASS	_ACCELIOC(3)
+
+/** set the accel scaling constants to the structure pointed to by (arg) */
+#define ACCELIOCSSCALE		_ACCELIOC(5)
+
+/** get the accel scaling constants into the structure pointed to by (arg) */
+#define ACCELIOCGSCALE		_ACCELIOC(6)
+
+/** set the accel measurement range to handle at least (arg) g */
+#define ACCELIOCSRANGE		_ACCELIOC(7)
+
+/** get the current accel measurement range in g */
+#define ACCELIOCGRANGE		_ACCELIOC(8)
+
+/** get the result of a sensor self-test */
+#define ACCELIOCSELFTEST	_ACCELIOC(9)
+
+#endif /* _DRV_ACCEL_H */
diff --git a/src/drivers/drv_adc.h b/src/drivers/drv_adc.h
new file mode 100644
index 000000000..8ec6d1233
--- /dev/null
+++ b/src/drivers/drv_adc.h
@@ -0,0 +1,52 @@
+/****************************************************************************
+ *
+ *   Copyright (C) 2012 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file drv_adc.h
+ *
+ * ADC driver interface.
+ *
+ * This defines additional operations over and above the standard NuttX
+ * ADC API.
+ */
+
+#pragma once
+
+#include <stdint.h>
+#include <sys/ioctl.h>
+
+#define ADC_DEVICE_PATH		"/dev/adc0"
+
+/*
+ * ioctl definitions
+ */
diff --git a/src/drivers/drv_baro.h b/src/drivers/drv_baro.h
new file mode 100644
index 000000000..176f798c0
--- /dev/null
+++ b/src/drivers/drv_baro.h
@@ -0,0 +1,78 @@
+/****************************************************************************
+ *
+ *   Copyright (C) 2012 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file Barometric pressure sensor driver interface.
+ */
+
+#ifndef _DRV_BARO_H
+#define _DRV_BARO_H
+
+#include <stdint.h>
+#include <sys/ioctl.h>
+
+#include "drv_sensor.h"
+#include "drv_orb_dev.h"
+
+#define BARO_DEVICE_PATH	"/dev/baro"
+
+/**
+ * baro report structure.  Reads from the device must be in multiples of this
+ * structure.
+ */
+struct baro_report {
+	float pressure;
+	float altitude;
+	float temperature;
+	uint64_t timestamp;
+};
+
+/*
+ * ObjDev tag for raw barometer data.
+ */
+ORB_DECLARE(sensor_baro);
+
+/*
+ * ioctl() definitions
+ */
+
+#define _BAROIOCBASE		(0x2200)
+#define _BAROIOC(_n)		(_IOC(_BAROIOCBASE, _n))
+
+/** set corrected MSL pressure in pascals */
+#define BAROIOCSMSLPRESSURE	_BAROIOC(0)
+
+/** get current MSL pressure in pascals */
+#define BAROIOCGMSLPRESSURE	_BAROIOC(1)
+
+#endif /* _DRV_BARO_H */
diff --git a/src/drivers/drv_blinkm.h b/src/drivers/drv_blinkm.h
new file mode 100644
index 000000000..9c278f6c5
--- /dev/null
+++ b/src/drivers/drv_blinkm.h
@@ -0,0 +1,69 @@
+/****************************************************************************
+ *
+ *   Copyright (C) 2012 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file drv_blinkm.h
+ *
+ * BlinkM driver API
+ *
+ * This could probably become a more generalised API for multi-colour LED
+ * driver systems, or be merged with the generic LED driver.
+ */
+
+#pragma once
+
+#include <stdint.h>
+#include <sys/ioctl.h>
+
+#define BLINKM_DEVICE_PATH	"/dev/blinkm"
+
+/*
+ * ioctl() definitions
+ */
+
+#define _BLINKMIOCBASE		(0x2900)
+#define _BLINKMIOC(_n)		(_IOC(_BLINKMIOCBASE, _n))
+
+/** play the named script in *(char *)arg, repeating forever */
+#define BLINKM_PLAY_SCRIPT_NAMED	_BLINKMIOC(1)
+
+/** play the numbered script in (arg), repeating forever */
+#define BLINKM_PLAY_SCRIPT		_BLINKMIOC(2)
+
+/** 
+ * Set the user script; (arg) is a pointer to an array of script lines,
+ * where each line is an array of four bytes giving <duration>, <command>, arg[0-2]
+ *
+ * The script is terminated by a zero command.
+ */
+#define BLINKM_SET_USER_SCRIPT		_BLINKMIOC(3)
diff --git a/src/drivers/drv_gpio.h b/src/drivers/drv_gpio.h
new file mode 100644
index 000000000..92d184326
--- /dev/null
+++ b/src/drivers/drv_gpio.h
@@ -0,0 +1,148 @@
+/****************************************************************************
+ *
+ *   Copyright (C) 2012 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file drv_gpio.h
+ *
+ * Generic GPIO ioctl interface.
+ */
+
+#ifndef _DRV_GPIO_H
+#define _DRV_GPIO_H
+
+#include <sys/ioctl.h>
+
+#ifdef CONFIG_ARCH_BOARD_PX4FMU
+/*
+ * PX4FMU GPIO numbers.
+ *
+ * For shared pins, alternate function 1 selects the non-GPIO mode 
+ * (USART2, CAN2, etc.)
+ */
+# define GPIO_EXT_1		(1<<0)		/**< high-power GPIO 1 */
+# define GPIO_EXT_2		(1<<1)		/**< high-power GPIO 1 */
+# define GPIO_MULTI_1		(1<<2)		/**< USART2 CTS */
+# define GPIO_MULTI_2		(1<<3)		/**< USART2 RTS */
+# define GPIO_MULTI_3		(1<<4)		/**< USART2 TX */
+# define GPIO_MULTI_4		(1<<5)		/**< USART2 RX */
+# define GPIO_CAN_TX		(1<<6)		/**< CAN2 TX */
+# define GPIO_CAN_RX		(1<<7)		/**< CAN2 RX */
+
+/**
+ * Default GPIO device - other devices may also support this protocol if
+ * they also export GPIO-like things.  This is always the GPIOs on the
+ * main board.
+ */
+# define GPIO_DEVICE_PATH	"/dev/px4fmu"
+
+#endif
+
+#ifdef CONFIG_ARCH_BOARD_PX4IO
+/*
+ * PX4IO GPIO numbers.
+ *
+ * XXX note that these are here for reference/future use; currently
+ * there is no good way to wire these up without a common STM32 GPIO
+ * driver, which isn't implemented yet.
+ */
+/* outputs */
+# define GPIO_ACC1_POWER	(1<<0)		/**< accessory power 1 */
+# define GPIO_ACC2_POWER	(1<<1)		/**< accessory power 2 */
+# define GPIO_SERVO_POWER	(1<<2)		/**< servo power */
+# define GPIO_RELAY1		(1<<3)		/**< relay 1 */
+# define GPIO_RELAY2		(1<<4)		/**< relay 2 */
+# define GPIO_LED_BLUE		(1<<5)		/**< blue LED */
+# define GPIO_LED_AMBER		(1<<6)		/**< amber/red LED */
+# define GPIO_LED_SAFETY	(1<<7)		/**< safety LED */
+
+/* inputs */
+# define GPIO_ACC_OVERCURRENT	(1<<8)		/**< accessory 1/2 overcurrent detect */
+# define GPIO_SERVO_OVERCURRENT	(1<<9)		/**< servo overcurrent detect */
+# define GPIO_SAFETY_BUTTON	(1<<10)		/**< safety button pressed */
+
+/**
+ * Default GPIO device - other devices may also support this protocol if
+ * they also export GPIO-like things.  This is always the GPIOs on the
+ * main board.
+ */
+# define GPIO_DEVICE_PATH	"/dev/px4io"
+
+#endif
+
+#ifndef GPIO_DEVICE_PATH
+#  error No GPIO support for this board.
+#endif
+
+/*
+ * IOCTL definitions.
+ *
+ * For all ioctls, the (arg) argument is a bitmask of GPIOs to be affected
+ * by the operation, with the LSB being the lowest-numbered GPIO.
+ *
+ * Note that there may be board-specific relationships between GPIOs;
+ * applications using GPIOs should be aware of this.
+ */
+#define _GPIOCBASE	0x2700
+#define GPIOC(_x)	_IOC(_GPIOCBASE, _x)
+
+/** reset all board GPIOs to their default state */
+#define GPIO_RESET	GPIOC(0)
+
+/** configure the board GPIOs in (arg) as outputs */
+#define GPIO_SET_OUTPUT	GPIOC(1)
+
+/** configure the board GPIOs in (arg) as inputs */
+#define GPIO_SET_INPUT	GPIOC(2)
+
+/** configure the board GPIOs in (arg) for the first alternate function (if supported) */
+#define GPIO_SET_ALT_1	GPIOC(3)
+
+/** configure the board GPIO (arg) for the second alternate function (if supported) */
+#define GPIO_SET_ALT_2	GPIOC(4)
+
+/** configure the board GPIO (arg) for the third alternate function (if supported) */
+#define GPIO_SET_ALT_3	GPIOC(5)
+
+/** configure the board GPIO (arg) for the fourth alternate function (if supported) */
+#define GPIO_SET_ALT_4	GPIOC(6)
+
+/** set the GPIOs in (arg) */
+#define GPIO_SET	GPIOC(10)
+
+/** clear the GPIOs in (arg) */
+#define GPIO_CLEAR	GPIOC(11)
+
+/** read all the GPIOs and return their values in *(uint32_t *)arg */
+#define GPIO_GET	GPIOC(12)
+
+#endif /* _DRV_GPIO_H */
\ No newline at end of file
diff --git a/src/drivers/drv_gps.h b/src/drivers/drv_gps.h
new file mode 100644
index 000000000..1dda8ef0b
--- /dev/null
+++ b/src/drivers/drv_gps.h
@@ -0,0 +1,70 @@
+/****************************************************************************
+ *
+ *   Copyright (C) 2012 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file GPS driver interface.
+ */
+
+#ifndef _DRV_GPS_H
+#define _DRV_GPS_H
+
+#include <stdint.h>
+#include <sys/ioctl.h>
+
+#include "drv_sensor.h"
+#include "drv_orb_dev.h"
+
+#define GPS_DEFAULT_UART_PORT "/dev/ttyS3"
+
+#define GPS_DEVICE_PATH	"/dev/gps"
+
+typedef enum {
+	GPS_DRIVER_MODE_NONE = 0,
+	GPS_DRIVER_MODE_UBX,
+	GPS_DRIVER_MODE_MTK,
+	GPS_DRIVER_MODE_NMEA,
+} gps_driver_mode_t;
+
+
+/*
+ * ObjDev tag for GPS data.
+ */
+ORB_DECLARE(gps);
+
+/*
+ * ioctl() definitions
+ */
+#define _GPSIOCBASE			(0x2800)            //TODO: arbitrary choice...
+#define _GPSIOC(_n)		(_IOC(_GPSIOCBASE, _n))
+
+#endif /* _DRV_GPS_H */
diff --git a/src/drivers/drv_gyro.h b/src/drivers/drv_gyro.h
new file mode 100644
index 000000000..1d0fef6fc
--- /dev/null
+++ b/src/drivers/drv_gyro.h
@@ -0,0 +1,117 @@
+/****************************************************************************
+ *
+ *   Copyright (C) 2012 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file Gyroscope driver interface.
+ */
+
+#ifndef _DRV_GYRO_H
+#define _DRV_GYRO_H
+
+#include <stdint.h>
+#include <sys/ioctl.h>
+
+#include "drv_sensor.h"
+#include "drv_orb_dev.h"
+
+#define GYRO_DEVICE_PATH	"/dev/gyro"
+
+/**
+ * gyro report structure.  Reads from the device must be in multiples of this
+ * structure.
+ */
+struct gyro_report {
+	uint64_t timestamp;
+	float x;		/**< angular velocity in the NED X board axis in rad/s */
+	float y;		/**< angular velocity in the NED Y board axis in rad/s */
+	float z;		/**< angular velocity in the NED Z board axis in rad/s */
+	float temperature;	/**< temperature in degrees celcius */
+	float range_rad_s;
+	float scaling;
+
+	int16_t x_raw;
+	int16_t y_raw;
+	int16_t z_raw;
+	int16_t temperature_raw;
+};
+
+/** gyro scaling factors; Vout = (Vin * Vscale) + Voffset */
+struct gyro_scale {
+	float	x_offset;
+	float	x_scale;
+	float	y_offset;
+	float	y_scale;
+	float	z_offset;
+	float	z_scale;
+};
+
+/*
+ * ObjDev tag for raw gyro data.
+ */
+ORB_DECLARE(sensor_gyro);
+
+/*
+ * ioctl() definitions
+ */
+
+#define _GYROIOCBASE		(0x2300)
+#define _GYROIOC(_n)		(_IOC(_GYROIOCBASE, _n))
+
+/** set the gyro internal sample rate to at least (arg) Hz */
+#define GYROIOCSSAMPLERATE	_GYROIOC(0)
+
+/** return the gyro internal sample rate in Hz */
+#define GYROIOCGSAMPLERATE	_GYROIOC(1)
+
+/** set the gyro internal lowpass filter to no lower than (arg) Hz */
+#define GYROIOCSLOWPASS		_GYROIOC(2)
+
+/** set the gyro internal lowpass filter to no lower than (arg) Hz */
+#define GYROIOCGLOWPASS		_GYROIOC(3)
+
+/** set the gyro scaling constants to (arg) */
+#define GYROIOCSSCALE		_GYROIOC(4)
+
+/** get the gyro scaling constants into (arg) */
+#define GYROIOCGSCALE		_GYROIOC(5)
+
+/** set the gyro measurement range to handle at least (arg) degrees per second */
+#define GYROIOCSRANGE		_GYROIOC(6)
+
+/** get the current gyro measurement range in degrees per second */
+#define GYROIOCGRANGE		_GYROIOC(7)
+
+/** check the status of the sensor */
+#define GYROIOCSELFTEST		_GYROIOC(8)
+
+#endif /* _DRV_GYRO_H */
diff --git a/src/drivers/drv_hrt.h b/src/drivers/drv_hrt.h
new file mode 100644
index 000000000..8a99eeca7
--- /dev/null
+++ b/src/drivers/drv_hrt.h
@@ -0,0 +1,149 @@
+/****************************************************************************
+ *
+ *   Copyright (C) 2012 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file drv_hrt.h
+ *
+ * High-resolution timer with callouts and timekeeping.
+ */
+
+#pragma once
+
+#include <sys/types.h>
+#include <stdbool.h>
+
+#include <time.h>
+#include <queue.h>
+
+__BEGIN_DECLS
+
+/*
+ * Absolute time, in microsecond units.
+ *
+ * Absolute time is measured from some arbitrary epoch shortly after
+ * system startup.  It should never wrap or go backwards.
+ */
+typedef uint64_t	hrt_abstime;
+
+/*
+ * Callout function type.
+ *
+ * Note that callouts run in the timer interrupt context, so
+ * they are serialised with respect to each other, and must not
+ * block.
+ */
+typedef void	(* hrt_callout)(void *arg);
+
+/*
+ * Callout record.
+ */
+typedef struct hrt_call {
+	struct sq_entry_s	link;
+
+	hrt_abstime		deadline;
+	hrt_abstime		period;
+	hrt_callout		callout;
+	void			*arg;
+} *hrt_call_t;
+
+/*
+ * Get absolute time.
+ */
+__EXPORT extern hrt_abstime hrt_absolute_time(void);
+
+/*
+ * Convert a timespec to absolute time.
+ */
+__EXPORT extern hrt_abstime ts_to_abstime(struct timespec *ts);
+
+/*
+ * Convert absolute time to a timespec.
+ */
+__EXPORT extern void	abstime_to_ts(struct timespec *ts, hrt_abstime abstime);
+
+/*
+ * Compute the delta between a timestamp taken in the past
+ * and now.
+ *
+ * This function is safe to use even if the timestamp is updated
+ * by an interrupt during execution.
+ */
+__EXPORT extern hrt_abstime hrt_elapsed_time(const volatile hrt_abstime *then);
+
+/*
+ * Store the absolute time in an interrupt-safe fashion.
+ *
+ * This function ensures that the timestamp cannot be seen half-written by an interrupt handler.
+ */
+__EXPORT extern hrt_abstime hrt_store_absolute_time(volatile hrt_abstime *now);
+
+/*
+ * Call callout(arg) after delay has elapsed.
+ *
+ * If callout is NULL, this can be used to implement a timeout by testing the call
+ * with hrt_called().
+ */
+__EXPORT extern void	hrt_call_after(struct hrt_call *entry, hrt_abstime delay, hrt_callout callout, void *arg);
+
+/*
+ * Call callout(arg) at absolute time calltime.
+ */
+__EXPORT extern void	hrt_call_at(struct hrt_call *entry, hrt_abstime calltime, hrt_callout callout, void *arg);
+
+/*
+ * Call callout(arg) after delay, and then after every interval.
+ *
+ * Note thet the interval is timed between scheduled, not actual, call times, so the call rate may
+ * jitter but should not drift.
+ */
+__EXPORT extern void	hrt_call_every(struct hrt_call *entry, hrt_abstime delay, hrt_abstime interval, hrt_callout callout, void *arg);
+
+/*
+ * If this returns true, the entry has been invoked and removed from the callout list,
+ * or it has never been entered.
+ *
+ * Always returns false for repeating callouts.
+ */
+__EXPORT extern bool	hrt_called(struct hrt_call *entry);
+
+/*
+ * Remove the entry from the callout list.
+ */
+__EXPORT extern void	hrt_cancel(struct hrt_call *entry);
+
+/*
+ * Initialise the HRT.
+ */
+__EXPORT extern void	hrt_init(void);
+
+__END_DECLS
diff --git a/src/drivers/drv_led.h b/src/drivers/drv_led.h
new file mode 100644
index 000000000..21044f620
--- /dev/null
+++ b/src/drivers/drv_led.h
@@ -0,0 +1,65 @@
+/****************************************************************************
+ *
+ *   Copyright (C) 2012 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file drv_led.h
+ *
+ * LED driver API
+ */
+
+#pragma once
+
+#include <stdint.h>
+#include <sys/ioctl.h>
+
+#define LED_DEVICE_PATH		"/dev/led"
+
+#define _LED_BASE		0x2800
+
+/* PX4 LED colour codes */
+#define LED_AMBER		1
+#define LED_RED			1	/* some boards have red rather than amber */
+#define LED_BLUE		0
+#define LED_SAFETY		2
+
+#define LED_ON			_IOC(_LED_BASE, 0)
+#define LED_OFF			_IOC(_LED_BASE, 1)
+
+__BEGIN_DECLS
+
+/*
+ * Initialise the LED driver.
+ */
+__EXPORT extern void drv_led_start(void);
+
+__END_DECLS
diff --git a/src/drivers/drv_mag.h b/src/drivers/drv_mag.h
new file mode 100644
index 000000000..9aab995a1
--- /dev/null
+++ b/src/drivers/drv_mag.h
@@ -0,0 +1,114 @@
+/****************************************************************************
+ *
+ *   Copyright (C) 2012 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file Magnetometer driver interface.
+ */
+
+#ifndef _DRV_MAG_H
+#define _DRV_MAG_H
+
+#include <stdint.h>
+#include <sys/ioctl.h>
+
+#include "drv_sensor.h"
+#include "drv_orb_dev.h"
+
+#define MAG_DEVICE_PATH		"/dev/mag"
+
+/**
+ * mag report structure.  Reads from the device must be in multiples of this
+ * structure.
+ *
+ * Output values are in gauss.
+ */
+struct mag_report {
+	uint64_t timestamp;
+	float x;
+	float y;
+	float z;
+	float range_ga;
+	float scaling;
+
+	int16_t x_raw;
+	int16_t y_raw;
+	int16_t z_raw;
+};
+
+/** mag scaling factors; Vout = (Vin * Vscale) + Voffset */
+struct mag_scale {
+	float	x_offset;
+	float	x_scale;
+	float	y_offset;
+	float	y_scale;
+	float	z_offset;
+	float	z_scale;
+};
+
+/*
+ * ObjDev tag for raw magnetometer data.
+ */
+ORB_DECLARE(sensor_mag);
+
+/*
+ * ioctl() definitions
+ */
+
+#define _MAGIOCBASE		(0x2400)
+#define _MAGIOC(_n)		(_IOC(_MAGIOCBASE, _n))
+
+/** set the mag internal sample rate to at least (arg) Hz */
+#define MAGIOCSSAMPLERATE	_MAGIOC(0)
+
+/** set the mag internal lowpass filter to no lower than (arg) Hz */
+#define MAGIOCSLOWPASS		_MAGIOC(1)
+
+/** set the mag scaling constants to the structure pointed to by (arg) */
+#define MAGIOCSSCALE		_MAGIOC(2)
+
+/** copy the mag scaling constants to the structure pointed to by (arg) */
+#define MAGIOCGSCALE		_MAGIOC(3)
+
+/** set the measurement range to handle (at least) arg Gauss */
+#define MAGIOCSRANGE		_MAGIOC(4)
+
+/** perform self-calibration, update scale factors to canonical units */
+#define MAGIOCCALIBRATE		_MAGIOC(5)
+
+/** excite strap */
+#define MAGIOCEXSTRAP		_MAGIOC(6)
+
+/** perform self test and report status */
+#define MAGIOCSELFTEST		_MAGIOC(7)
+
+#endif /* _DRV_MAG_H */
diff --git a/src/drivers/drv_mixer.h b/src/drivers/drv_mixer.h
new file mode 100644
index 000000000..9f43015d9
--- /dev/null
+++ b/src/drivers/drv_mixer.h
@@ -0,0 +1,118 @@
+/****************************************************************************
+ *
+ *   Copyright (C) 2012 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file drv_mixer.h
+ *
+ * Mixer ioctl interfaces.
+ *
+ * Normal workflow is:
+ *
+ * - open mixer device
+ * - add mixer(s)
+ * loop:
+ *  - mix actuators to array
+ *
+ * Each client has its own configuration.
+ *
+ * When mixing, outputs are produced by mixers in the order they are
+ * added.  A simple mixer produces one output; a multotor mixer will
+ * produce several outputs, etc.
+ */
+
+#ifndef _DRV_MIXER_H
+#define _DRV_MIXER_H
+
+#include <stdint.h>
+#include <sys/ioctl.h>
+
+#define MIXER_DEVICE_PATH		"/dev/mixer"
+
+/*
+ * ioctl() definitions
+ */
+#define _MIXERIOCBASE		(0x2500)
+#define _MIXERIOC(_n)		(_IOC(_MIXERIOCBASE, _n))
+
+/** get the number of mixable outputs */
+#define MIXERIOCGETOUTPUTCOUNT	_MIXERIOC(0)
+
+/** reset (clear) the mixer configuration */
+#define MIXERIOCRESET		_MIXERIOC(1)
+
+/** simple channel scaler */
+struct mixer_scaler_s {
+	float			negative_scale;
+	float			positive_scale;
+	float			offset;
+	float			min_output;
+	float			max_output;
+};
+
+/** mixer input */
+struct mixer_control_s {
+	uint8_t			control_group;	/**< group from which the input reads */
+	uint8_t			control_index;	/**< index within the control group */
+	struct mixer_scaler_s 	scaler;		/**< scaling applied to the input before use */
+};
+
+/** simple mixer */
+struct mixer_simple_s {
+	uint8_t			control_count;	/**< number of inputs */
+	struct mixer_scaler_s	output_scaler;	/**< scaling for the output */
+	struct mixer_control_s	controls[0];	/**< actual size of the array is set by control_count */
+};
+
+#define MIXER_SIMPLE_SIZE(_icount)	(sizeof(struct mixer_simple_s) + (_icount) * sizeof(struct mixer_control_s))
+
+/**
+ * add a simple mixer in (struct mixer_simple_s *)arg
+ */
+#define MIXERIOCADDSIMPLE	_MIXERIOC(2)
+
+/* _MIXERIOC(3) was deprecated */
+/* _MIXERIOC(4) was deprecated */
+
+/**
+ * Add mixer(s) from the buffer in (const char *)arg
+ */
+#define MIXERIOCLOADBUF		_MIXERIOC(5)
+
+/*
+ * XXX Thoughts for additional operations:
+ *
+ * - get/set output scale, for tuning center/limit values.
+ * - save/serialise for saving tuned mixers.
+ */
+
+#endif /* _DRV_ACCEL_H */
diff --git a/src/drivers/drv_orb_dev.h b/src/drivers/drv_orb_dev.h
new file mode 100644
index 000000000..713618545
--- /dev/null
+++ b/src/drivers/drv_orb_dev.h
@@ -0,0 +1,87 @@
+/****************************************************************************
+ *
+ *   Copyright (C) 2012 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+#ifndef _DRV_UORB_H
+#define _DRV_UORB_H
+
+/**
+ * @file uORB published object driver.
+ */
+
+#include <sys/types.h>
+#include <sys/ioctl.h>
+#include <stdint.h>
+
+/* XXX for ORB_DECLARE used in many drivers */
+#include "../modules/uORB/uORB.h"
+
+/*
+ * ioctl() definitions
+ */
+
+/** path to the uORB control device for pub/sub topics */
+#define TOPIC_MASTER_DEVICE_PATH	"/obj/_obj_"
+
+/** path to the uORB control device for parameter topics */
+#define PARAM_MASTER_DEVICE_PATH	"/param/_param_"
+
+/** maximum ogbject name length */
+#define ORB_MAXNAME		32
+
+#define _ORBIOCBASE		(0x2600)
+#define _ORBIOC(_n)		(_IOC(_ORBIOCBASE, _n))
+
+/*
+ * IOCTLs for the uORB control device
+ */
+
+/** Advertise a new topic described by *(uorb_metadata *)arg */
+#define ORBIOCADVERTISE		_ORBIOC(0)
+
+/*
+ * IOCTLs for individual topics.
+ */
+
+/** Fetch the time at which the topic was last updated into *(uint64_t *)arg */
+#define ORBIOCLASTUPDATE	_ORBIOC(10)
+
+/** Check whether the topic has been updated since it was last read, sets *(bool *)arg */
+#define ORBIOCUPDATED		_ORBIOC(11)
+
+/** Set the minimum interval at which the topic can be seen to be updated for this subscription */
+#define ORBIOCSETINTERVAL	_ORBIOC(12)
+
+/** Get the global advertiser handle for the topic */
+#define ORBIOCGADVERTISER	_ORBIOC(13)
+
+#endif /* _DRV_UORB_H */
diff --git a/src/drivers/drv_pwm_output.h b/src/drivers/drv_pwm_output.h
new file mode 100644
index 000000000..07831f20c
--- /dev/null
+++ b/src/drivers/drv_pwm_output.h
@@ -0,0 +1,201 @@
+/****************************************************************************
+ *
+ *   Copyright (C) 2012 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file PWM servo output interface.
+ *
+ * Servo values can be set with the PWM_SERVO_SET ioctl, by writing a
+ * pwm_output_values structure to the device, or by publishing to the
+ * output_pwm ORB topic.
+ * Writing a value of 0 to a channel suppresses any output for that
+ * channel.
+ */
+
+#pragma once
+
+#include <stdint.h>
+#include <sys/ioctl.h>
+
+#include "drv_orb_dev.h"
+
+__BEGIN_DECLS
+
+/**
+ * Path for the default PWM output device.
+ *
+ * Note that on systems with more than one PWM output path (e.g.
+ * PX4FMU with PX4IO connected) there may be other devices that
+ * respond to this protocol.
+ */
+#define PWM_OUTPUT_DEVICE_PATH	"/dev/pwm_output"
+
+/**
+ * Maximum number of PWM output channels supported by the device.
+ */
+#define PWM_OUTPUT_MAX_CHANNELS	16
+
+/**
+ * Servo output signal type, value is actual servo output pulse
+ * width in microseconds.
+ */
+typedef uint16_t	servo_position_t;
+
+/**
+ * Servo output status structure.
+ *
+ * May be published to output_pwm, or written to a PWM output
+ * device.
+ */
+struct pwm_output_values {
+	/** desired pulse widths for each of the supported channels */
+	servo_position_t	values[PWM_OUTPUT_MAX_CHANNELS];
+};
+
+/*
+ * ORB tag for PWM outputs.
+ */
+ORB_DECLARE(output_pwm);
+
+/*
+ * ioctl() definitions
+ *
+ * Note that ioctls and ORB updates should not be mixed, as the
+ * behaviour of the system in this case is not defined.
+ */
+#define _PWM_SERVO_BASE		0x2a00
+
+/** arm all servo outputs handle by this driver */
+#define PWM_SERVO_ARM		_IOC(_PWM_SERVO_BASE, 0)
+
+/** disarm all servo outputs (stop generating pulses) */
+#define PWM_SERVO_DISARM	_IOC(_PWM_SERVO_BASE, 1)
+
+/** set alternate servo update rate */
+#define PWM_SERVO_SET_UPDATE_RATE _IOC(_PWM_SERVO_BASE, 2)
+
+/** get the number of servos in *(unsigned *)arg */
+#define PWM_SERVO_GET_COUNT	_IOC(_PWM_SERVO_BASE, 3)
+
+/** selects servo update rates, one bit per servo. 0 = default (50Hz), 1 = alternate */
+#define PWM_SERVO_SELECT_UPDATE_RATE _IOC(_PWM_SERVO_BASE, 4)
+
+/** set a single servo to a specific value */
+#define PWM_SERVO_SET(_servo)	_IOC(_PWM_SERVO_BASE, 0x20 + _servo)
+
+/** get a single specific servo value */
+#define PWM_SERVO_GET(_servo)	_IOC(_PWM_SERVO_BASE, 0x40 + _servo)
+
+/** get the _n'th rate group's channels; *(uint32_t *)arg returns a bitmap of channels
+ *  whose update rates must be the same.
+ */
+#define PWM_SERVO_GET_RATEGROUP(_n) _IOC(_PWM_SERVO_BASE, 0x60 + _n)
+
+/*
+ * Low-level PWM output interface.
+ *
+ * This is the low-level API to the platform-specific PWM driver.
+ */
+
+/**
+ * Intialise the PWM servo outputs using the specified configuration.
+ *
+ * @param channel_mask	Bitmask of channels (LSB = channel 0) to enable.
+ *			This allows some of the channels to remain configured
+ *			as GPIOs or as another function.
+ * @return		OK on success.
+ */
+__EXPORT extern int	up_pwm_servo_init(uint32_t channel_mask);
+
+/**
+ * De-initialise the PWM servo outputs.
+ */
+__EXPORT extern void	up_pwm_servo_deinit(void);
+
+/**
+ * Arm or disarm servo outputs.
+ *
+ * When disarmed, servos output no pulse.
+ *
+ * @bug This function should, but does not, guarantee that any pulse
+ *      currently in progress is cleanly completed.
+ *
+ * @param armed		If true, outputs are armed; if false they
+ *			are disarmed.
+ */
+__EXPORT extern void	up_pwm_servo_arm(bool armed);
+
+/**
+ * Set the servo update rate for all rate groups.
+ *
+ * @param rate		The update rate in Hz to set.
+ * @return		OK on success, -ERANGE if an unsupported update rate is set.
+ */
+__EXPORT extern int	up_pwm_servo_set_rate(unsigned rate);
+
+/**
+ * Get a bitmap of output channels assigned to a given rate group.
+ *
+ * @param group		The rate group to query. Rate groups are assigned contiguously
+ *			starting from zero.
+ * @return		A bitmap of channels assigned to the rate group, or zero if
+ *			the group number has no channels.
+ */
+__EXPORT extern uint32_t up_pwm_servo_get_rate_group(unsigned group);
+
+/**
+ * Set the update rate for a given rate group.
+ *
+ * @param group		The rate group whose update rate will be changed.
+ * @param rate		The update rate in Hz.
+ * @return		OK if the group was adjusted, -ERANGE if an unsupported update rate is set.
+ */
+__EXPORT extern int	up_pwm_servo_set_rate_group_update(unsigned group, unsigned rate);
+
+/**
+ * Set the current output value for a channel.
+ *
+ * @param channel	The channel to set.
+ * @param value		The output pulse width in microseconds.
+ */
+__EXPORT extern int	up_pwm_servo_set(unsigned channel, servo_position_t value);
+
+/**
+ * Get the current output value for a channel.
+ *
+ * @param channel	The channel to read.
+ * @return		The output pulse width in microseconds, or zero if
+ *			outputs are not armed or not configured.
+ */
+__EXPORT extern servo_position_t up_pwm_servo_get(unsigned channel);
+
+__END_DECLS
diff --git a/src/drivers/drv_range_finder.h b/src/drivers/drv_range_finder.h
new file mode 100644
index 000000000..03a82ec5d
--- /dev/null
+++ b/src/drivers/drv_range_finder.h
@@ -0,0 +1,81 @@
+/****************************************************************************
+ *
+ *   Copyright (C) 2013 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file Rangefinder driver interface.
+ */
+
+#ifndef _DRV_RANGEFINDER_H
+#define _DRV_RANGEFINDER_H
+
+#include <stdint.h>
+#include <sys/ioctl.h>
+
+#include "drv_sensor.h"
+#include "drv_orb_dev.h"
+
+#define RANGE_FINDER_DEVICE_PATH	"/dev/range_finder"
+
+/**
+ * range finder report structure.  Reads from the device must be in multiples of this
+ * structure.
+ */
+struct range_finder_report {
+	uint64_t timestamp;
+	float distance; 			/** in meters */
+	uint8_t valid;				/** 1 == within sensor range, 0 = outside sensor range */
+};
+
+/*
+ * ObjDev tag for raw range finder data.
+ */
+ORB_DECLARE(sensor_range_finder);
+
+/*
+ * ioctl() definitions
+ *
+ * Rangefinder drivers also implement the generic sensor driver
+ * interfaces from drv_sensor.h
+ */
+
+#define _RANGEFINDERIOCBASE			(0x7900)
+#define __RANGEFINDERIOC(_n)		(_IOC(_RANGEFINDERIOCBASE, _n))
+
+/** set the minimum effective distance of the device */
+#define RANGEFINDERIOCSETMINIUMDISTANCE	__RANGEFINDERIOC(1)
+
+/** set the maximum effective distance of the device */
+#define RANGEFINDERIOCSETMAXIUMDISTANCE	__RANGEFINDERIOC(2)
+
+
+#endif /* _DRV_RANGEFINDER_H */
diff --git a/src/drivers/drv_rc_input.h b/src/drivers/drv_rc_input.h
new file mode 100644
index 000000000..4decc324e
--- /dev/null
+++ b/src/drivers/drv_rc_input.h
@@ -0,0 +1,110 @@
+/****************************************************************************
+ *
+ *   Copyright (C) 2012 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file R/C input interface.
+ *
+ */
+
+#ifndef _DRV_RC_INPUT_H
+#define _DRV_RC_INPUT_H
+
+#include <stdint.h>
+#include <sys/ioctl.h>
+
+#include "drv_orb_dev.h"
+
+/**
+ * Path for the default R/C input device.
+ *
+ * Note that on systems with more than one R/C input path (e.g.
+ * PX4FMU with PX4IO connected) there may be other devices that
+ * respond to this protocol.
+ *
+ * Input data may be obtained by subscribing to the input_rc
+ * object, or by poll/reading from the device.
+ */
+#define RC_INPUT_DEVICE_PATH	"/dev/input_rc"
+
+/**
+ * Maximum number of R/C input channels in the system. S.Bus has up to 18 channels.
+ */
+#define RC_INPUT_MAX_CHANNELS	18
+
+/**
+ * Input signal type, value is a control position from zero to 100
+ * percent.
+ */
+typedef uint16_t		rc_input_t;
+
+enum RC_INPUT_SOURCE {
+	RC_INPUT_SOURCE_UNKNOWN = 0,
+	RC_INPUT_SOURCE_PX4FMU_PPM,
+	RC_INPUT_SOURCE_PX4IO_PPM,
+	RC_INPUT_SOURCE_PX4IO_SPEKTRUM,
+	RC_INPUT_SOURCE_PX4IO_SBUS
+};
+
+/**
+ * R/C input status structure.
+ *
+ * Published to input_rc, may also be published to other names depending
+ * on the board involved.
+ */
+struct rc_input_values {
+	/** decoding time */
+	uint64_t		timestamp;
+
+	/** number of channels actually being seen */
+	uint32_t		channel_count;
+
+	/** Input source */
+	enum RC_INPUT_SOURCE 	input_source;
+
+	/** measured pulse widths for each of the supported channels */
+	rc_input_t		values[RC_INPUT_MAX_CHANNELS];
+};
+
+/*
+ * ObjDev tag for R/C inputs.
+ */
+ORB_DECLARE(input_rc);
+
+#define _RC_INPUT_BASE		0x2b00
+
+/** Fetch R/C input values into (rc_input_values *)arg */
+
+#define RC_INPUT_GET			_IOC(_RC_INPUT_BASE, 0)
+
+
+#endif /* _DRV_RC_INPUT_H */
diff --git a/src/drivers/drv_sensor.h b/src/drivers/drv_sensor.h
new file mode 100644
index 000000000..3a89cab9d
--- /dev/null
+++ b/src/drivers/drv_sensor.h
@@ -0,0 +1,87 @@
+/****************************************************************************
+ *
+ *   Copyright (C) 2012 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file Common sensor API and ioctl definitions.
+ */
+
+#ifndef _DRV_SENSOR_H
+#define _DRV_SENSOR_H
+
+#include <stdint.h>
+#include <sys/ioctl.h>
+
+/*
+ * ioctl() definitions
+ *
+ * Note that a driver may not implement all of these operations, but
+ * if the operation is implemented it should conform to this API.
+ */
+
+#define _SENSORIOCBASE		(0x2000)
+#define _SENSORIOC(_n)		(_IOC(_SENSORIOCBASE, _n))
+
+/**
+ * Set the driver polling rate to (arg) Hz, or one of the SENSOR_POLLRATE
+ * constants
+ */
+#define SENSORIOCSPOLLRATE	_SENSORIOC(0)
+
+/**
+ * Return the driver's approximate polling rate in Hz, or one of the
+ * SENSOR_POLLRATE values.
+ */
+#define SENSORIOCGPOLLRATE	_SENSORIOC(1)
+
+#define SENSOR_POLLRATE_MANUAL		1000000	/**< poll when read */
+#define SENSOR_POLLRATE_EXTERNAL	1000001	/**< poll when device signals ready */
+#define SENSOR_POLLRATE_MAX		1000002	/**< poll at device maximum rate */
+#define SENSOR_POLLRATE_DEFAULT		1000003	/**< poll at driver normal rate */
+
+/**
+ * Set the internal queue depth to (arg) entries, must be at least 1
+ *
+ * This sets the upper bound on the number of readings that can be
+ * read from the driver.
+ */
+#define SENSORIOCSQUEUEDEPTH	_SENSORIOC(2)
+
+/** return the internal queue depth */
+#define SENSORIOCGQUEUEDEPTH	_SENSORIOC(3)
+
+/**
+ * Reset the sensor to its default configuration.
+ */
+#define SENSORIOCRESET		_SENSORIOC(4)
+
+#endif /* _DRV_SENSOR_H */
\ No newline at end of file
diff --git a/src/drivers/drv_tone_alarm.h b/src/drivers/drv_tone_alarm.h
new file mode 100644
index 000000000..0c6afc64c
--- /dev/null
+++ b/src/drivers/drv_tone_alarm.h
@@ -0,0 +1,128 @@
+/****************************************************************************
+ *
+ *   Copyright (C) 2012 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/*
+ * Driver for the PX4 audio alarm port, /dev/tone_alarm.
+ *
+ * The tone_alarm driver supports a set of predefined "alarm"
+ * patterns and one user-supplied pattern.  Patterns are ordered by
+ * priority, with a higher-priority pattern interrupting any
+ * lower-priority pattern that might be playing.
+ *
+ * The TONE_SET_ALARM ioctl can be used to select a predefined
+ * alarm pattern, from 1 - <TBD>.  Selecting pattern zero silences
+ * the alarm.
+ *
+ * To supply a custom pattern, write an array of 1 - <TBD> tone_note
+ * structures to /dev/tone_alarm.  The custom pattern has a priority
+ * of zero.
+ *
+ * Patterns will normally play once and then silence (if a pattern
+ * was overridden it will not resume).  A pattern may be made to
+ * repeat by inserting a note with the duration set to
+ * DURATION_REPEAT.  This pattern will loop until either a
+ * higher-priority pattern is started or pattern zero is requested
+ * via the ioctl.
+ */
+
+#ifndef DRV_TONE_ALARM_H_
+#define DRV_TONE_ALARM_H_
+
+#include <sys/ioctl.h>
+
+#define _TONE_ALARM_BASE	0x7400
+#define TONE_SET_ALARM		_IOC(_TONE_ALARM_BASE, 1)
+
+/* structure describing one note in a tone pattern */
+struct tone_note {
+	uint8_t		pitch;
+	uint8_t		duration;	/* duration in multiples of 10ms */
+#define DURATION_END		0	/* ends the pattern */
+#define DURATION_REPEAT		255	/* resets the note counter to zero */
+};
+
+enum tone_pitch {
+	TONE_NOTE_E4,   /* E4 */
+	TONE_NOTE_F4,   /* F4 */
+	TONE_NOTE_F4S,  /* F#4/Gb4 */
+	TONE_NOTE_G4,   /* G4 */
+	TONE_NOTE_G4S,  /* G#4/Ab4 */
+	TONE_NOTE_A4,   /* A4 */
+	TONE_NOTE_A4S,  /* A#4/Bb4 */
+	TONE_NOTE_B4,   /* B4 */
+	TONE_NOTE_C5,   /* C5 */
+	TONE_NOTE_C5S,  /* C#5/Db5 */
+	TONE_NOTE_D5,   /* D5 */
+	TONE_NOTE_D5S,  /* D#5/Eb5 */
+	TONE_NOTE_E5,   /* E5 */
+	TONE_NOTE_F5,   /* F5 */
+	TONE_NOTE_F5S,  /* F#5/Gb5 */
+	TONE_NOTE_G5,   /* G5 */
+	TONE_NOTE_G5S,  /* G#5/Ab5 */
+	TONE_NOTE_A5,   /* A5 */
+	TONE_NOTE_A5S,  /* A#5/Bb5 */
+	TONE_NOTE_B5,   /* B5 */
+	TONE_NOTE_C6,   /* C6 */
+	TONE_NOTE_C6S,  /* C#6/Db6 */
+	TONE_NOTE_D6,   /* D6 */
+	TONE_NOTE_D6S,  /* D#6/Eb6 */
+	TONE_NOTE_E6,   /* E6 */
+	TONE_NOTE_F6,   /* F6 */
+	TONE_NOTE_F6S,  /* F#6/Gb6 */
+	TONE_NOTE_G6,   /* G6 */
+	TONE_NOTE_G6S,  /* G#6/Ab6 */
+	TONE_NOTE_A6,   /* A6 */
+	TONE_NOTE_A6S,  /* A#6/Bb6 */
+	TONE_NOTE_B6,   /* B6 */
+	TONE_NOTE_C7,   /* C7 */
+	TONE_NOTE_C7S,  /* C#7/Db7 */
+	TONE_NOTE_D7,   /* D7 */
+	TONE_NOTE_D7S,  /* D#7/Eb7 */
+	TONE_NOTE_E7,   /* E7 */
+	TONE_NOTE_F7,   /* F7 */
+	TONE_NOTE_F7S,  /* F#7/Gb7 */
+	TONE_NOTE_G7,   /* G7 */
+	TONE_NOTE_G7S,  /* G#7/Ab7 */
+	TONE_NOTE_A7,   /* A7 */
+	TONE_NOTE_A7S,  /* A#7/Bb7 */
+	TONE_NOTE_B7,   /* B7 */
+	TONE_NOTE_C8,   /* C8 */
+	TONE_NOTE_C8S,  /* C#8/Db8 */
+	TONE_NOTE_D8,   /* D8 */
+	TONE_NOTE_D8S,  /* D#8/Eb8 */
+
+	TONE_NOTE_SILENCE,
+	TONE_NOTE_MAX
+};
+
+#endif /* DRV_TONE_ALARM_H_ */
diff --git a/src/drivers/led/Makefile b/src/drivers/led/Makefile
new file mode 100644
index 000000000..7de188259
--- /dev/null
+++ b/src/drivers/led/Makefile
@@ -0,0 +1,38 @@
+############################################################################
+#
+#   Copyright (C) 2012 PX4 Development Team. All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+#
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in
+#    the documentation and/or other materials provided with the
+#    distribution.
+# 3. Neither the name PX4 nor the names of its contributors may be
+#    used to endorse or promote products derived from this software
+#    without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+# FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+# COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+# BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+# OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+# AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+# ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+# POSSIBILITY OF SUCH DAMAGE.
+#
+############################################################################
+
+#
+# Makefile to build the LED driver.
+#
+
+include $(APPDIR)/mk/app.mk
diff --git a/src/drivers/led/led.cpp b/src/drivers/led/led.cpp
new file mode 100644
index 000000000..c7c45525e
--- /dev/null
+++ b/src/drivers/led/led.cpp
@@ -0,0 +1,115 @@
+/****************************************************************************
+ *
+ *   Copyright (C) 2012 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file led.cpp
+ *
+ * LED driver.
+ */
+
+#include <nuttx/config.h>
+#include <drivers/device/device.h>
+#include <drivers/drv_led.h>
+
+/* Ideally we'd be able to get these from up_internal.h */
+//#include <up_internal.h>
+__BEGIN_DECLS
+extern void up_ledinit();
+extern void up_ledon(int led);
+extern void up_ledoff(int led);
+__END_DECLS
+
+class LED : device::CDev
+{
+public:
+	LED();
+	virtual ~LED();
+
+	virtual int		init();
+	virtual int		ioctl(struct file *filp, int cmd, unsigned long arg);
+};
+
+LED::LED() :
+	CDev("led", LED_DEVICE_PATH)
+{
+	// force immediate init/device registration
+	init();
+}
+
+LED::~LED()
+{
+}
+
+int
+LED::init()
+{
+	CDev::init();
+	up_ledinit();
+
+	return 0;
+}
+
+int
+LED::ioctl(struct file *filp, int cmd, unsigned long arg)
+{
+	int result = OK;
+
+	switch (cmd) {
+	case LED_ON:
+		up_ledon(arg);
+		break;
+
+	case LED_OFF:
+		up_ledoff(arg);
+		break;
+
+	default:
+		result = CDev::ioctl(filp, cmd, arg);
+	}
+	return result;
+}
+
+namespace
+{
+LED	*gLED;
+}
+
+void
+drv_led_start()
+{
+	if (gLED == nullptr) {
+		gLED = new LED;
+		if (gLED != nullptr)
+			gLED->init();
+	}
+}
\ No newline at end of file