a) dynamically loadable control surface support

b) move tranzport and generic midi into separate dirs under "surfaces"


git-svn-id: svn://localhost/trunk/ardour2@442 d708f5d6-7413-0410-9779-e7cbd77b26cf

20 files changed, 356 insertions, 293 deletions

diff --git a/SConstruct b/SConstruct
index 0806ac4d26..04d1b3545f 100644
--- a/SConstruct
+++ b/SConstruct
@@ -518,6 +518,11 @@ else:
     'gtk2_ardour'
         ]
 
+surface_subdirs = [
+    'libs/surfaces/tranzport',
+    'libs/surfaces/generic_midi'
+    ]
+
 opts.Save('scache.conf', env)
 Help(opts.GenerateHelpText(env))
 
@@ -791,7 +796,7 @@ env.AddPostAction (srcdist, Action ('rm -rf ' + str (File (env['DISTTREE']))))
 for subdir in coredirs:
     SConscript (subdir + '/SConscript')
 
-for sublistdir in [subdirs, gtk_subdirs]:
+for sublistdir in [subdirs, gtk_subdirs, surface_subdirs]:
 	for subdir in sublistdir:
 	        SConscript (subdir + '/SConscript')
 
diff --git a/gtk2_ardour/arval b/gtk2_ardour/arval
index 5254ad4df0..a91943fb4d 100755
--- a/gtk2_ardour/arval
+++ b/gtk2_ardour/arval
@@ -1,3 +1,3 @@
 #!/bin/sh
 source ardev_common.sh
-exec valgrind --num-callers=12 --tool=memcheck ./ardour.bin --novst $*
+exec valgrind --db-attach=yes --num-callers=12 --tool=memcheck ./ardour.bin --novst $*
diff --git a/libs/ardour/SConscript b/libs/ardour/SConscript
index 8bf62b9c01..572851d2f2 100644
--- a/libs/ardour/SConscript
+++ b/libs/ardour/SConscript
@@ -32,6 +32,7 @@ automation_event.cc
 configuration.cc
 connection.cc
 control_protocol.cc
+control_protocol_manager.cc
 crossfade.cc
 curve.cc
 cycle_timer.cc
@@ -42,7 +43,6 @@ externalsource.cc
 filesource.cc
 gain.cc
 gdither.cc
-generic_midi_control_protocol.cc
 globals.cc
 import.cc
 insert.cc
@@ -69,10 +69,8 @@ send.cc
 session.cc
 session_butler.cc
 session_click.cc
-session_control.cc
 session_events.cc
 session_export.cc
-session_feedback.cc
 session_midi.cc
 session_process.cc
 session_state.cc
@@ -85,7 +83,6 @@ source.cc
 state_manager.cc
 stateful.cc
 tempo.cc
-tranzport_control_protocol.cc
 utils.cc
 version.cc
 mix.cc
diff --git a/libs/ardour/ardour/control_protocol.h b/libs/ardour/ardour/control_protocol.h
index c0869fad9a..4088e2dd09 100644
--- a/libs/ardour/ardour/control_protocol.h
+++ b/libs/ardour/ardour/control_protocol.h
@@ -16,7 +16,8 @@ class ControlProtocol : sigc::trackable {
 	virtual ~ControlProtocol();
 
 	virtual int init () { return 0; }
-	virtual bool active() const = 0;
+
+	sigc::signal<void> ActiveChanged;
 
 	enum SendWhat {
 		SendRoute,
@@ -26,6 +27,9 @@ class ControlProtocol : sigc::trackable {
 	std::string name() const { return _name; }
 
 	void set_send (SendWhat);
+	void set_active (bool yn);
+	bool get_active() const { return active_thread > 0; }
+
 
 	bool send() const { return _send != 0; }
 	bool send_route_feedback () const { return _send & SendRoute; }
@@ -35,11 +39,43 @@ class ControlProtocol : sigc::trackable {
 	virtual void send_global_feedback () {}
 
   protected:
+
 	ARDOUR::Session& session;
 	SendWhat _send;
 	std::string _name;
+	int active_thread;
+	int thread_request_pipe[2];
+	pthread_t _thread;
+
+	static void* _thread_work (void *);
+	void* thread_work ();
+
+	struct ThreadRequest {
+	    enum Type {
+		    Start,
+		    Stop,
+		    Quit
+	    };
+	};
+
+	int init_thread();
+	int start_thread ();
+	int stop_thread ();
+	void terminate_thread ();
+	int  poke_thread (ThreadRequest::Type);
 };
 
+extern "C" {
+	struct ControlProtocolDescriptor {
+	    const char* name;
+	    void*       ptr;
+	    void*       module;
+	    ControlProtocol* (*initialize)(ControlProtocolDescriptor*,Session*);
+	    void             (*destroy)(ControlProtocolDescriptor*,ControlProtocol*);
+	    
+	};
+}
+
 }
 
 #endif // ardour_control_protocols_h
diff --git a/libs/ardour/ardour/session.h b/libs/ardour/ardour/session.h
index 1f6f464d24..201cc48ada 100644
--- a/libs/ardour/ardour/session.h
+++ b/libs/ardour/ardour/session.h
@@ -79,8 +79,7 @@ class AudioRegion;
 class Region;
 class Playlist;
 class VSTPlugin;
-class ControlProtocol;
-class GenericMidiControlProtocol;
+class ControlProtocolManager;
 
 struct AudioExportSpecification;
 struct RouteGroup;
@@ -246,6 +245,8 @@ class Session : public sigc::trackable, public Stateful
 	std::string dead_sound_dir () const;
 	std::string automation_dir () const;
 
+	static string suffixed_search_path (std::string suffix);
+	static string control_protocol_path ();
 	static string template_path ();
 	static string template_dir ();
 	static void get_template_list (list<string>&);
@@ -428,7 +429,6 @@ class Session : public sigc::trackable, public Stateful
 	void set_do_not_record_plugins (bool yn);
 	void set_crossfades_active (bool yn);
 	void set_seamless_loop (bool yn);
-	void set_feedback (bool yn);
 
 	bool get_auto_play () const { return auto_play; }
 	bool get_auto_input () const { return auto_input; }
@@ -445,8 +445,6 @@ class Session : public sigc::trackable, public Stateful
 	bool get_midi_control () const;
 	bool get_do_not_record_plugins () const { return do_not_record_plugins; }
 	bool get_crossfades_active () const { return crossfades_active; }
-	bool get_feedback() const;
-	bool get_tranzport_control() const;
 
 	bool get_input_auto_connect () const;
 	AutoConnectOption get_output_auto_connect () const { return output_auto_connect; }
@@ -1136,7 +1134,6 @@ class Session : public sigc::trackable, public Stateful
 	bool send_mmc;
 	bool mmc_control;
 	bool midi_control;
-	bool midi_feedback;
 
 	RingBuffer<Event*> pending_events;
 
@@ -1363,31 +1360,6 @@ class Session : public sigc::trackable, public Stateful
 	void send_time_code_in_another_thread (bool full);
 	void send_mmc_in_another_thread (MIDI::MachineControl::Command, jack_nframes_t frame = 0);
 
-	/* Feedback */
-
-	typedef sigc::slot<int> FeedbackFunctionPtr;
-	static void* _feedback_thread_work (void *);
-	void* feedback_thread_work ();
-	int feedback_generic_midi_function ();
-	std::list<FeedbackFunctionPtr> feedback_functions;
-	int active_feedback;
-	int feedback_request_pipe[2];
-	pthread_t feedback_thread;
-
-	struct FeedbackRequest {
-	    enum Type {
-		    Start,
-		    Stop,
-		    Quit
-	    };
-	};
-
-	int init_feedback();
-	int start_feedback ();
-	int stop_feedback ();
-	void terminate_feedback ();
-	int  poke_feedback (FeedbackRequest::Type);
-
 	jack_nframes_t adjust_apparent_position (jack_nframes_t frames);
 	
 	void reset_record_status ();
@@ -1770,12 +1742,6 @@ class Session : public sigc::trackable, public Stateful
 
 	LayerModel layer_model;
 	CrossfadeModel xfade_model;
-
-	/* control protocols */
-
-	vector<ControlProtocol*> control_protocols;
-	GenericMidiControlProtocol* generic_midi_control_protocol;
-	void initialize_control ();
 };
 
 }; /* namespace ARDOUR */
diff --git a/libs/ardour/globals.cc b/libs/ardour/globals.cc
index 7210fcf9f5..18fad73f09 100644
--- a/libs/ardour/globals.cc
+++ b/libs/ardour/globals.cc
@@ -46,6 +46,7 @@
 #include <ardour/source.h>
 #include <ardour/utils.h>
 #include <ardour/session.h>
+#include <ardour/control_protocol_manager.h>
 
 #include <ardour/mix.h>
 
@@ -71,7 +72,6 @@ Change ARDOUR::PositionChanged = ARDOUR::new_change ();
 Change ARDOUR::NameChanged = ARDOUR::new_change ();
 Change ARDOUR::BoundsChanged = Change (0); // see init(), below
 
-
 static int 
 setup_midi ()
 {
@@ -266,6 +266,10 @@ ARDOUR::init (AudioEngine& engine, bool use_vst, bool try_optimization, void (*s
 	/* singleton - first object is "it" */
 	new PluginManager (engine);
 	
+	/* singleton - first object is "it" */
+	new ControlProtocolManager ();
+	ControlProtocolManager::instance().discover_control_protocols (Session::control_protocol_path());
+	
 	BoundsChanged = Change (StartChanged|PositionChanged|LengthChanged);
 
 	return 0;
diff --git a/libs/ardour/session.cc b/libs/ardour/session.cc
index 22686c6cbe..216517e668 100644
--- a/libs/ardour/session.cc
+++ b/libs/ardour/session.cc
@@ -361,7 +361,6 @@ Session::~Session ()
 	
 	terminate_butler_thread ();
 	terminate_midi_thread ();
-	terminate_feedback ();
 	
 	if (click_data && click_data != default_click) {
 		delete [] click_data;
diff --git a/libs/ardour/session_feedback.cc b/libs/ardour/session_feedback.cc
index 09e9021461..600567892e 100644
--- a/libs/ardour/session_feedback.cc
+++ b/libs/ardour/session_feedback.cc
@@ -45,198 +45,5 @@ using namespace std;
 using namespace ARDOUR;
 //using namespace sigc;
 
-int
-Session::init_feedback ()
-{
-	if (pipe (feedback_request_pipe) != 0) {
-		error << string_compose (_("cannot create feedback request pipe (%1)"),
-				  strerror (errno))
-		      << endmsg;
-		return -1;
-	}
-
-	if (fcntl (feedback_request_pipe[0], F_SETFL, O_NONBLOCK)) {
-		error << string_compose(_("UI: cannot set O_NONBLOCK on "    "signal read pipe (%1)"), strerror (errno)) << endmsg;
-		return -1;
-	}
-
-	if (fcntl (feedback_request_pipe[1], F_SETFL, O_NONBLOCK)) {
-		error << string_compose(_("UI: cannot set O_NONBLOCK on "    "signal write pipe (%1)"), strerror (errno)) << endmsg;
-		return -1;
-	}
-
-	active_feedback = 0;
-
-	if (pthread_create_and_store ("feedback", &feedback_thread, 0, _feedback_thread_work, this)) {
-		error << _("Session: could not create feedback thread") << endmsg;
-		return -1;
-	}
-
-	return 0;
-}	
-
-int
-Session::poke_feedback (FeedbackRequest::Type why)
-{
-	char c = (char) why;
-	return !(write (feedback_request_pipe[1], &c, 1) == 1);
-}
-
-int
-Session::start_feedback ()
-{
-	return poke_feedback (FeedbackRequest::Start);
-}
-
-int
-Session::stop_feedback ()
-{
-	return poke_feedback (FeedbackRequest::Stop);
-}
-
-void
-Session::set_feedback (bool yn)
-{
-	set_dirty();
-
-	if (yn) {
-		/* make sure the feedback thread is alive */
-		start_feedback ();
-	} else {
-		/* maybe put the feedback thread to sleep */
-		stop_feedback ();
-	}
-
-	ControlChanged (Feedback); /* EMIT SIGNAL */
-}
-
-bool
-Session::get_feedback() const
-{
-	return active_feedback > 0;
-}
-
-void
-Session::terminate_feedback ()
-{
-	void* status;
-	poke_feedback (FeedbackRequest::Quit);
-	pthread_join (feedback_thread, &status);
-}
-
-void*
-Session::_feedback_thread_work (void* arg)
-{
-	return static_cast<Session*> (arg)->feedback_thread_work ();
-}
-
-void*
-Session::feedback_thread_work ()
-{
-	PBD::ThreadCreated (pthread_self(), X_("Feedback"));
-	struct pollfd pfd[1];
-	int timeout;
-
-	pthread_setcancelstate (PTHREAD_CANCEL_ENABLE, 0);
-	pthread_setcanceltype (PTHREAD_CANCEL_ASYNCHRONOUS, 0);
-
-	if (active_feedback) {
-		timeout = max (5, (int) Config->get_feedback_interval_ms());
-	} else {
-		timeout = -1;
-	}
-
-	while (1) {
-
-		pfd[0].fd = feedback_request_pipe[0];
-		pfd[0].events = POLLIN|POLLHUP|POLLERR;
-
-		if (poll (pfd, 1, timeout) < 0) {
-			if (errno == EINTR) {
-				continue;
-			}
-			error << string_compose (_("Feedback thread poll failed (%1)"),
-					  strerror (errno))
-			      << endmsg;
-			break;
-		}
-
-		if (pfd[0].revents & ~POLLIN) {
-			error << _("Error on feedback thread request pipe") << endmsg;
-			break;
-		}
-
-		if (pfd[0].revents & POLLIN) {
-
-			char req;
-			
-			/* empty the pipe of all current requests */
-
-			while (1) {
-				size_t nread = read (feedback_request_pipe[0], &req, sizeof (req));
-
-				if (nread == 1) {
-					switch ((FeedbackRequest::Type) req) {
-					
-					case FeedbackRequest::Start:
-						timeout = max (5, (int) Config->get_feedback_interval_ms());
-						active_feedback++;
-						break;
-						
-					case FeedbackRequest::Stop:
-						timeout = -1;
-						if (active_feedback) {
-							active_feedback--;
-						} 
-						break;
-						
-					case FeedbackRequest::Quit:
-						pthread_exit_pbd (0);
-						/*NOTREACHED*/
-						break;
-						
-					default:
-						break;
-					}
-
-				} else if (nread == 0) {
-					break;
-				} else if (errno == EAGAIN) {
-					break;
-				} else {
-					fatal << _("Error reading from feedback request pipe") << endmsg;
-					/*NOTREACHED*/
-				}
-			}
-		}
-		
-		if (!active_feedback || transport_stopped()) {
-			continue;
-		}
-
-		bool send = false;
-
-		for (vector<ControlProtocol*>::iterator i = control_protocols.begin(); i != control_protocols.end(); ++i) {
-			if ((*i)->send()) {
-				send = true;
-				break;
-			}
-		}
-		
-		if (send) {
-
-			RouteList routes = get_routes(); /* copies the routes */
-
-			for (vector<ControlProtocol*>::iterator i = control_protocols.begin(); i != control_protocols.end(); ++i) {
-				if ((*i)->send_route_feedback ()) {
-					(*i)->send_route_feedback (routes);
-				}
-				(*i)->send_global_feedback ();
-			} 
-		}
-	}
-	
-	return 0;
-}
 
 	
diff --git a/libs/ardour/session_midi.cc b/libs/ardour/session_midi.cc
index af08d3cc3e..aa079f8827 100644
--- a/libs/ardour/session_midi.cc
+++ b/libs/ardour/session_midi.cc
@@ -40,7 +40,6 @@
 #include <ardour/diskstream.h>
 #include <ardour/slave.h>
 #include <ardour/cycles.h>
-#include <ardour/generic_midi_control_protocol.h>
 
 #include "i18n.h"
 
@@ -170,19 +169,12 @@ Session::set_send_mmc (bool yn)
 void
 Session::set_midi_feedback (bool yn)
 {
-	if (generic_midi_control_protocol) {
-		if (yn) {
-			generic_midi_control_protocol->set_send (ControlProtocol::SendRoute);
-		} else {
-			generic_midi_control_protocol->set_send (ControlProtocol::SendWhat (0));
-		}
-	}
 }
 
 bool
 Session::get_midi_feedback () const
 {
-	return generic_midi_control_protocol && generic_midi_control_protocol->active();
+	return false;
 }
 
 bool
@@ -328,9 +320,9 @@ Session::set_midi_port (string port_tag)
 
 	_midi_port = port;
 	
-	if (generic_midi_control_protocol) {
-		generic_midi_control_protocol->set_port (port);
-	}
+	/* XXX need something to forward this to control protocols ? or just
+	   use the signal below 
+	*/
 
 	Config->set_midi_port_name (port_tag);
 
diff --git a/libs/ardour/session_state.cc b/libs/ardour/session_state.cc
index 5decba1d09..a78a2bdfa7 100644
--- a/libs/ardour/session_state.cc
+++ b/libs/ardour/session_state.cc
@@ -81,6 +81,7 @@
 #include <ardour/location.h>
 #include <ardour/audioregion.h>
 #include <ardour/crossfade.h>
+#include <ardour/control_protocol_manager.h>
 
 #include "i18n.h"
 #include <locale.h>
@@ -165,9 +166,7 @@ Session::first_stage_init (string fullpath, string snapshot_name)
 	butler_mixdown_buffer = 0;
 	butler_gain_buffer = 0;
 	auditioner = 0;
-	generic_midi_control_protocol = 0;
 	mmc_control = false;
-	midi_feedback = false;
 	midi_control = true;
 	mmc = 0;
 	post_transport_work = PostTransportWork (0);
@@ -302,12 +301,6 @@ Session::second_stage_init (bool new_session)
 		return -1;
 	}
 
-	initialize_control();
-	
-	if (init_feedback ()) {
-		return -1;
-	}
-
 	if (state_tree) {
 		if (set_state (*state_tree->root())) {
 			return -1;
@@ -348,7 +341,7 @@ Session::second_stage_init (bool new_session)
 	deliver_mmc (MIDI::MachineControl::cmdMmcReset, 0);
 	deliver_mmc (MIDI::MachineControl::cmdLocate, 0);
 
-	// XXX need to poke the feedback thread to send full state
+	ControlProtocolManager::instance().startup (*this);
 
 	if (new_session) {
 		_end_location_is_free = true;
@@ -2300,7 +2293,7 @@ Session::template_dir ()
 }
 
 string
-Session::template_path ()
+Session::suffixed_search_path (string suffix)
 {
 	string path;
 
@@ -2317,7 +2310,8 @@ Session::template_path ()
 
 	for (vector<string>::iterator i = split_path.begin(); i != split_path.end(); ++i) {
 		path += *i;
-		path += "templates/";
+		path += suffix;
+		path += '/';
 		
 		if (distance (i, split_path.end()) != 1) {
 			path += ':';
@@ -2327,6 +2321,18 @@ Session::template_path ()
 	return path;
 }
 
+string
+Session::template_path ()
+{
+	return suffixed_search_path (X_("templates"));
+}
+
+string
+Session::control_protocol_path ()
+{
+	return suffixed_search_path (X_("surfaces"));
+}
+
 int
 Session::load_connections (const XMLNode& node)
 {
diff --git a/libs/ardour/utils.cc b/libs/ardour/utils.cc
index a5b0b4f2ce..8e9a36de59 100644
--- a/libs/ardour/utils.cc
+++ b/libs/ardour/utils.cc
@@ -257,3 +257,4 @@ path_expand (string path)
 	return path;
 #endif
 }
+
diff --git a/libs/pbd3/pthread_utils.cc b/libs/pbd3/pthread_utils.cc
index 88e9aef195..323542cdf7 100644
--- a/libs/pbd3/pthread_utils.cc
+++ b/libs/pbd3/pthread_utils.cc
@@ -25,7 +25,7 @@
 
 #include <pbd/pthread_utils.h>
 
-using std::string;
+using namespace std;
 
 typedef std::map<string,pthread_t> ThreadMap;
 static ThreadMap all_threads;
@@ -43,6 +43,8 @@ pthread_create_and_store (string name, pthread_t  *thread, pthread_attr_t *attr,
 {
 	int ret;
 
+	cerr << "Creating thread " << name << endl;
+
 	if ((ret = pthread_create (thread, attr, start_routine, arg)) == 0) {
 		std::pair<string,pthread_t> newpair;
 		newpair.first = name;
diff --git a/libs/surfaces/generic_midi/SConscript b/libs/surfaces/generic_midi/SConscript
new file mode 100644
index 0000000000..abede3f4d7
--- /dev/null
+++ b/libs/surfaces/generic_midi/SConscript
@@ -0,0 +1,51 @@
+# -*- python -*-
+
+import os
+import glob
+
+Import('env final_prefix install_prefix final_config_prefix libraries i18n')
+
+genericmidi = env.Copy()
+
+#
+# this defines the version number of libardour_genericmidi
+# 
+
+domain = 'ardour_genericmidi'
+
+genericmidi.Append(DOMAIN = domain, MAJOR = 1, MINOR = 0, MICRO = 0)
+genericmidi.Append(CXXFLAGS = "-DPACKAGE=\\\"" + domain + "\\\"")
+genericmidi.Append(CXXFLAGS="-DLIBSIGC_DISABLE_DEPRECATED")
+genericmidi.Append(PACKAGE = domain)
+genericmidi.Append(POTFILE = domain + '.pot')
+
+genericmidi_files=Split("""
+interface.cc
+generic_midi_control_protocol.cc
+""")
+
+genericmidi.Append(CCFLAGS="-D_REENTRANT -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE")
+genericmidi.Append(CXXFLAGS="-DDATA_DIR=\\\""+final_prefix+"/share\\\"")
+genericmidi.Append(CXXFLAGS="-DCONFIG_DIR=\\\""+final_config_prefix+"\\\"")
+genericmidi.Append(CXXFLAGS="-DLOCALEDIR=\\\""+final_prefix+"/share/locale\\\"")
+
+genericmidi.Merge ([
+	     libraries['usb'],
+	     libraries['ardour'],
+	     libraries['sigc2'],
+	     libraries['pbd3'],
+	     libraries['midi++2'],
+	     libraries['xml']
+	     ])
+
+libardour_genericmidi = genericmidi.SharedLibrary('ardour_genericmidi', genericmidi_files)
+
+Default(libardour_genericmidi)
+
+if env['NLS']:
+	i18n (genericmidi, genericmidi_files, env)
+	      
+env.Alias('tarball', env.Distribute (env['DISTTREE'],
+				     [ 'SConscript', 'i18n.h', 'gettext.h' ] +
+				     genericmidi_files + 
+				     glob.glob('po/*.po') + glob.glob('*.h')))
diff --git a/libs/ardour/generic_midi_control_protocol.cc b/libs/surfaces/generic_midi/generic_midi_control_protocol.cc
index f9b9750982..4d64c6ce23 100644
--- a/libs/ardour/generic_midi_control_protocol.cc
+++ b/libs/surfaces/generic_midi/generic_midi_control_protocol.cc
@@ -1,7 +1,8 @@
-#include <ardour/generic_midi_control_protocol.h>
 #include <ardour/route.h>
 #include <ardour/session.h>
 
+#include "generic_midi_control_protocol.h"
+
 using namespace ARDOUR;
 
 #include "i18n.h"
diff --git a/libs/ardour/ardour/generic_midi_control_protocol.h b/libs/surfaces/generic_midi/generic_midi_control_protocol.h
index 75b514f016..75b514f016 100644
--- a/libs/ardour/ardour/generic_midi_control_protocol.h
+++ b/libs/surfaces/generic_midi/generic_midi_control_protocol.h
diff --git a/libs/surfaces/generic_midi/interface.cc b/libs/surfaces/generic_midi/interface.cc
new file mode 100644
index 0000000000..8283b92e6f
--- /dev/null
+++ b/libs/surfaces/generic_midi/interface.cc
@@ -0,0 +1,34 @@
+#include <ardour/control_protocol.h>
+
+#include "generic_midi_control_protocol.h"
+
+using namespace ARDOUR;
+
+ControlProtocol*
+new_generic_midi_protocol (ControlProtocolDescriptor* descriptor, Session* s)
+{
+	return new GenericMidiControlProtocol (*s);
+}
+
+void
+delete_generic_midi_protocol (ControlProtocolDescriptor* descriptor, ControlProtocol* cp)
+{
+	delete cp;
+}
+
+static ControlProtocolDescriptor generic_midi_descriptor = {
+	name : "Generic MIDI",
+	ptr : 0,
+	module : 0,
+	initialize : new_generic_midi_protocol,
+	destroy : delete_generic_midi_protocol
+};
+	
+
+extern "C" {
+ControlProtocolDescriptor* 
+protocol_descriptor () {
+	return &generic_midi_descriptor;
+}
+}
+
diff --git a/libs/surfaces/tranzport/SConscript b/libs/surfaces/tranzport/SConscript
new file mode 100644
index 0000000000..e43f0bc77c
--- /dev/null
+++ b/libs/surfaces/tranzport/SConscript
@@ -0,0 +1,52 @@
+# -*- python -*-
+
+import os
+import glob
+
+Import('env final_prefix install_prefix final_config_prefix libraries i18n')
+
+tranzport = env.Copy()
+
+#
+# this defines the version number of libardour_tranzport
+# 
+
+domain = 'ardour_tranzport'
+
+tranzport.Append(DOMAIN = domain, MAJOR = 1, MINOR = 0, MICRO = 0)
+tranzport.Append(CXXFLAGS = "-DPACKAGE=\\\"" + domain + "\\\"")
+tranzport.Append(CXXFLAGS="-DLIBSIGC_DISABLE_DEPRECATED")
+tranzport.Append(PACKAGE = domain)
+tranzport.Append(POTFILE = domain + '.pot')
+
+tranzport_files=Split("""
+interface.cc
+tranzport_control_protocol.cc
+""")
+
+tranzport.Append(CCFLAGS="-D_REENTRANT -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE")
+tranzport.Append(CXXFLAGS="-DDATA_DIR=\\\""+final_prefix+"/share\\\"")
+tranzport.Append(CXXFLAGS="-DCONFIG_DIR=\\\""+final_config_prefix+"\\\"")
+tranzport.Append(CXXFLAGS="-DLOCALEDIR=\\\""+final_prefix+"/share/locale\\\"")
+
+tranzport.Append(CPPPATH=libraries['ardour'].get ('CPPPATH', []))
+tranzport.Append(CPPPATH=libraries['sigc2'].get ('CPPPATH', []))
+tranzport.Append(CPPPATH=libraries['pbd3'].get ('CPPPATH', []))
+tranzport.Append(CPPPATH=libraries['midi++2'].get ('CPPPATH', []))
+
+tranzport.Merge ([
+	libraries['xml'],
+	libraries['usb']
+	])
+
+libardour_tranzport = tranzport.SharedLibrary('ardour_tranzport', tranzport_files)
+
+Default(libardour_tranzport)
+
+if env['NLS']:
+	i18n (tranzport, tranzport_files, env)
+	      
+env.Alias('tarball', env.Distribute (env['DISTTREE'],
+				     [ 'SConscript', 'i18n.h', 'gettext.h' ] +
+				     tranzport_files + 
+				     glob.glob('po/*.po') + glob.glob('*.h')))
diff --git a/libs/surfaces/tranzport/interface.cc b/libs/surfaces/tranzport/interface.cc
new file mode 100644
index 0000000000..a731be2ddf
--- /dev/null
+++ b/libs/surfaces/tranzport/interface.cc
@@ -0,0 +1,34 @@
+#include <ardour/control_protocol.h>
+
+#include "tranzport_control_protocol.h"
+
+using namespace ARDOUR;
+
+ControlProtocol*
+new_tranzport_protocol (ControlProtocolDescriptor* descriptor, Session* s)
+{
+	return new TranzportControlProtocol (*s);
+}
+
+void
+delete_tranzport_protocol (ControlProtocolDescriptor* descriptor, ControlProtocol* cp)
+{
+	delete cp;
+}
+
+static ControlProtocolDescriptor tranzport_descriptor = {
+	name : "Tranzport",
+	ptr : 0,
+	module : 0,
+	initialize : new_tranzport_protocol,
+	destroy : delete_tranzport_protocol
+};
+	
+
+extern "C" {
+ControlProtocolDescriptor* 
+protocol_descriptor () {
+	return &tranzport_descriptor;
+}
+}
+
diff --git a/libs/ardour/tranzport_control_protocol.cc b/libs/surfaces/tranzport/tranzport_control_protocol.cc
index 9640ea4a75..518a4387d1 100644
--- a/libs/ardour/tranzport_control_protocol.cc
+++ b/libs/surfaces/tranzport/tranzport_control_protocol.cc
@@ -1,11 +1,13 @@
 #include <iostream>
+#include <sys/time.h>
 
 #include <pbd/pthread_utils.h>
 
-#include <ardour/tranzport_control_protocol.h>
 #include <ardour/route.h>
 #include <ardour/session.h>
 
+#include "tranzport_control_protocol.h"
+
 using namespace ARDOUR;
 using namespace std;
 
@@ -22,11 +24,14 @@ TranzportControlProtocol::TranzportControlProtocol (Session& s)
 	current_route = 0;
 	current_track_id = 0;
 	last_where = max_frames;
+	memset (next_screen, ' ', sizeof (next_screen));
+	memset (current_screen, ' ', sizeof (current_screen));
 }
 
 TranzportControlProtocol::~TranzportControlProtocol ()
 {
 	if (udev) {
+		lcd_clear ();
 		pthread_cancel_one (thread);
 		close ();
 	}
@@ -39,7 +44,13 @@ TranzportControlProtocol::init ()
 		return -1;
 	}
 
-	pthread_create_and_store (X_("Tranzport"), &thread, 0, _thread_work, this);
+	/* outbound thread */
+
+	init_thread ();
+
+	/* inbound thread */
+	
+	pthread_create_and_store (X_("tranzport monitor"), &thread, 0, _thread_work, this);
 
 	return 0;
 }
@@ -58,16 +69,24 @@ TranzportControlProtocol::send_route_feedback (list<Route*>& routes)
 void
 TranzportControlProtocol::send_global_feedback ()
 {
-	jack_nframes_t where = session.transport_frame();
+	show_transport_time ();
+
+	flush_lcd ();
+}
 
+void
+TranzportControlProtocol::show_transport_time ()
+{
+	jack_nframes_t where = session.transport_frame();
+	
 	if (where != last_where) {
 
-		char clock_label[16];
+		uint8_t label[12];
 		SMPTE_Time smpte;
-		char* ptr = clock_label;
+		char* ptr = (char *) label;
 
 		session.smpte_time (where, smpte);
-		memset (clock_label, ' ', sizeof (clock_label));
+		memset (label, ' ', sizeof (label));
 		
 		if (smpte.negative) {
 			sprintf (ptr, "-%02ld:", smpte.hours);
@@ -85,14 +104,57 @@ TranzportControlProtocol::send_global_feedback ()
 		sprintf (ptr, "%02ld", smpte.frames);
 		ptr += 2;
 		
-		lcd_write (7, &clock_label[0]);
-		lcd_write (8, &clock_label[4]);
-		lcd_write (9, &clock_label[8]);
+		write_clock (label);
 
 		last_where = where;
 	}
 }
 
+void
+TranzportControlProtocol::write_clock (const uint8_t* label)
+{
+	memcpy (&next_screen[1][8], &label[0]);
+	memcpy (&next_screen[1][12], &label[4]);
+	memcpy (&next_screen[1][16], &label[8]);
+}
+
+void
+TranzportControlProtocol::flush_lcd ()
+{
+	if (memcmp (&next_screen[0][0], &current_screen[0][0], 4)) {
+		lcd_write (0, &next_screen[0][0]);
+	}
+	if (memcmp (&next_screen[0][4], &current_screen[0][4], 4)) {
+		lcd_write (1, &next_screen[0][0]);
+	}
+	if (memcmp (&next_screen[0][8], &current_screen[0][8], 4)) {
+		lcd_write (2, &next_screen[0][0]);
+	}
+	if (memcmp (&next_screen[0][12], &current_screen[0][12], 4)) {
+		lcd_write (3, &next_screen[0][0]);
+	}
+	if (memcmp (&next_screen[0][16], &current_screen[0][16], 4)) {
+		lcd_write (4, &next_screen[0][0]);
+	}
+	if (memcmp (&next_screen[1][0], &current_screen[1][0], 4)) {
+		lcd_write (5, &next_screen[0][0]);
+	}
+	if (memcmp (&next_screen[1][4], &current_screen[1][4], 4)) {
+		lcd_write (6, &next_screen[0][0]);
+	}
+	if (memcmp (&next_screen[1][8], &current_screen[1][8], 4)) {
+		lcd_write (7, &next_screen[0][0]);
+	}
+	if (memcmp (&next_screen[1][12], &current_screen[1][12], 4)) {
+		lcd_write (8, &next_screen[0][0]);
+	}
+	if (memcmp (&next_screen[1][16], &current_screen[1][16], 4)) {
+		lcd_write (9, &next_screen[0][0]);
+	}
+
+	memcpy (current_screen, next_screen, sizeof (current_screen));
+}
+
 void*
 TranzportControlProtocol::_thread_work (void* arg)
 {
@@ -102,7 +164,7 @@ TranzportControlProtocol::_thread_work (void* arg)
 void*
 TranzportControlProtocol::thread_work ()
 {
-	cerr << "tranzport thread here, sending message to LCD\n";
+	PBD::ThreadCreated (pthread_self(), X_("tranzport monitor"));
 
 	while (true) {
 		if (read()) {
@@ -138,7 +200,6 @@ TranzportControlProtocol::thread_work ()
 
 	while (true) {
 		if (read ()) {
-			cerr << "Tranzport command received\n";
 			break;
 		}
 	}
@@ -156,19 +217,13 @@ TranzportControlProtocol::open ()
 	usb_find_busses();
 	usb_find_devices();
 
-	cerr << "checking busses\n";
-	
 	for (bus = usb_busses; bus; bus = bus->next) {
 
-		cerr << "checking devices\n";
-
 		for(dev = bus->devices; dev; dev = dev->next) {
-			cerr << "Checking " << dev->descriptor.idVendor << '/' << dev->descriptor.idProduct << endl;
 			if (dev->descriptor.idVendor != VENDORID)
 				continue;
 			if (dev->descriptor.idProduct != PRODUCTID)
 				continue;
-			cerr << "Open this one" << endl;
 			return open_core (dev);
 		}
 	}
@@ -218,14 +273,20 @@ TranzportControlProtocol::close ()
 }
 	
 int
-TranzportControlProtocol::write (uint8_t* cmd)
+TranzportControlProtocol::write (uint8_t* cmd, uint32_t timeout_override)
 {
 	int val;
-	val = usb_interrupt_write (udev, WRITE_ENDPOINT, (char*) cmd, 8, timeout);
+	struct timeval tv1, tv2, tv_diff;
+
+	gettimeofday (&tv1, 0);
+	val = usb_interrupt_write (udev, WRITE_ENDPOINT, (char*) cmd, 8, timeout_override ? timeout_override : timeout);
+	gettimeofday (&tv2, 0);
 	if (val < 0)
 		return val;
 	if (val != 8)
 		return -1;
+	timersub (&tv2, &tv1, &tv_diff);
+	cerr << "time to write command = " << tv_diff.tv_sec << '.' << tv_diff.tv_usec << endl;
 	return 0;
 
 }	
@@ -263,7 +324,15 @@ TranzportControlProtocol::lcd_write (uint8_t cell, const char* text)
 	cmd[6] = text[3];
 	cmd[7] = 0x00;
 
-	return write (cmd);
+	int index = cell%4;
+	cell /= 4;
+
+	current_screen[cell][index] = text[0];
+	current_screen[cell][index+1] = text[1];
+	current_screen[cell][index+2] = text[2];
+	current_screen[cell][index+3] = text[3];
+
+	return write (cmd, 500);
 }
 
 int
@@ -280,7 +349,7 @@ TranzportControlProtocol::light_on (LightID light)
 	cmd[6] = 0x00;
 	cmd[7] = 0x00;
 
-	return write (cmd);
+	return write (cmd, 500);
 }
 
 int
@@ -297,27 +366,29 @@ TranzportControlProtocol::light_off (LightID light)
 	cmd[6] = 0x00;
 	cmd[7] = 0x00;
 
-	return write (cmd);
+	return write (cmd, 500);
 }
 
 int
-TranzportControlProtocol::read ()
+TranzportControlProtocol::read (uint32_t timeout_override)
 {
 	uint8_t buf[8];
 	int val;
 
 	memset(buf, 0, 8);
-	val = usb_interrupt_read(udev, READ_ENDPOINT, (char*) buf, 8, timeout);
+  again:
+	val = usb_interrupt_read(udev, READ_ENDPOINT, (char*) buf, 8, timeout_override ? timeout_override : timeout);
 	if (val < 0) {
-		cerr << "Tranzport read error, val = " << val << endl;
 		return val;
 	}
 	if (val != 8) {
-		cerr << "Tranzport short read, val = " << val << endl;
+		if (val == 0) {
+			goto again;
+		}
 		return -1;
 	}
 
-	/*printf("read: %02x %02x %02x %02x %02x %02x %02x %02x\n", buf[0], buf[1], buf[2], buf[3], buf[4], buf[5], buf[6], buf[7]);*/
+	/* printf("read: %02x %02x %02x %02x %02x %02x %02x %02x\n", buf[0], buf[1], buf[2], buf[3], buf[4], buf[5], buf[6], buf[7]);*/
 
 	uint32_t this_button_mask;
 	uint32_t button_changes;
diff --git a/libs/ardour/ardour/tranzport_control_protocol.h b/libs/surfaces/tranzport/tranzport_control_protocol.h
index 448d803c36..5880f3807a 100644
--- a/libs/ardour/ardour/tranzport_control_protocol.h
+++ b/libs/surfaces/tranzport/tranzport_control_protocol.h
@@ -69,6 +69,7 @@ class TranzportControlProtocol : public ControlProtocol {
 	usb_dev_handle* udev;
 	Route*          current_route;
 	uint32_t        current_track_id;
+	uint8_t         lcd_screen[2][20];
 
 	bool     last_negative;
 	uint32_t last_hrs;
@@ -78,8 +79,8 @@ class TranzportControlProtocol : public ControlProtocol {
 	jack_nframes_t last_where;
 
 	int open ();
-	int read ();
-	int write (uint8_t* cmd);
+	int read (uint32_t timeout_override = 0);
+	int write (uint8_t* cmd, uint32_t timeout_override = 0);
 	int close ();
 
 	int open_core (struct usb_device*);
@@ -90,7 +91,11 @@ class TranzportControlProtocol : public ControlProtocol {
 	int  light_on (LightID);
 	int  light_off (LightID);
 
+	void flush_lcd ();
+	void write_clock (const uint8_t* label);
+
 	void show_current_track ();
+	void show_transport_time ();
 
 	static void* _thread_work (void* arg);
 	void* thread_work ();