add signal monitoring support

7 files changed, 162 insertions, 26 deletions

diff --git a/Makefile b/Makefile
index 07cc811..be5a1e4 100644
--- a/Makefile
+++ b/Makefile
@@ -13,7 +13,7 @@ FMRXUTILS_LIBS:=$(shell pkg-config --libs $(FMRXUTILS_PKGS))
 
 all: fmrxd fmrx-cat fmrx-ctl
 
-fmrxd: fmrxd.o server.o radio.o bt.o capture.o tuner.o rds.o
+fmrxd: fmrxd.o server.o radio.o bt.o capture.o tuner.o rds.o signal.o
 	$(CC) $(FMRXD_LDFLAGS) $(LDFLAGS) -o $@ $+ $(LIBS) $(FMRXD_LIBS)
 
 fmrx-cat: fmrx-cat.o
diff --git a/debian/changelog b/debian/changelog
index f307b8a..5841332 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,3 +1,9 @@
+fmrxd (0.2) unstable; urgency=low
+
+  * Add signal level monitoring.
+
+ -- Javier S. Pedro <maemo@javispedro.com>  Mon, 13 Feb 2012 20:15:30 +0100
+
 fmrxd (0.1) unstable; urgency=low
 
   * Initial Release.
diff --git a/fmrxd.h b/fmrxd.h
index 5f95d6a..9473510 100644
--- a/fmrxd.h
+++ b/fmrxd.h
@@ -6,32 +6,49 @@
 #include <stdbool.h>
 #include <glib.h>
 
+/** The D-Bus name of this server. */
 #define BUS_NAME      "com.javispedro.fmrxd"
 #define BUS_PATH      "/com/javispedro/fmrxd"
 #define BUS_INTERFACE BUS_NAME
 
+/** Whether the server will shutdown when there are no more clients. */
 #define SERVER_ON_DEMAND    1
+/** Seconds the server will wait before shutting down after last client exits. */
 #define SERVER_LINGER_TIME	10
 
+/** Seconds the server will keep the radio device powered on after the last
+ client exits. Should be smaller than SERVER_LINGER_TIME. */
 #define RADIO_LINGER_TIME   2
 
+/** The BlueZ device ID to power up and configure. */
 #define BT_DEV_ID 0
 
+/** The ALSA mixer node to configure. */
 #define ALSA_MIXER_NAME "hw:2"
+/** The ALSA device from where to read radio audio data. */
 #define ALSA_PCM_CAPTURE_NAME "hw:2,0"
+/** The audio rate to use. */
 #define ALSA_CAPTURE_RATE 48000
 
+/** The size of the global ring buffer size that prevents overruns. */
 #define RING_BUFFER_SIZE (ALSA_CAPTURE_RATE)
 
+/** Tuner device to use. */
 #define TUNER_DEVICE "/dev/radio0"
 #define TUNER_DEVICE_ID 0
 
+/** Enable the wl1273 N950/N9 RDS decoding workarounds. */
 #define CRAPPY_WL1273_RDS 1
 
-/* fmrxd.c */
+/** Poll the signal level every this many seconds. */
+#define SIGNAL_POLL_INTERVAL 10
+/** After tuning, refresh the signal level once after this many miliseconds. */
+#define SIGNAL_REFRESH_DELAY 200
+
+/* fmrxd.c -- the main loop */
 extern GMainLoop* main_loop;
 
-/* server.c */
+/* server.c -- the d-bus server, audio server and client logic */
 int server_start();
 void server_stop();
 void server_queue_stop();
@@ -40,38 +57,43 @@ size_t server_get_buffer(size_t size, void **buffer);
 void server_commit_buffer(size_t size);
 void server_notify_tuned(double mhz);
 void server_notify_stopped();
+void server_notify_signal(uint16_t signal);
 void server_notify_pi(uint16_t pi);
 void server_notify_ps(const char *ps);
 void server_notify_rt(const char *rt);
 
-/* radio.c */
+/* radio.c -- enabling and disabling radio logic */
 bool radio_active();
 void radio_start();
 void radio_stop();
 void radio_queue_start();
 void radio_queue_stop();
 
-/* bt.c */
+/* bt.c -- configuring the wl1273 multiplexer via HCI */
 bool configure_bt_muxer(bool on);
 
-/* capture.c */
+/* capture.c -- configure the ALSA mixer and capture */
 bool configure_mixer(bool on);
 bool configure_capture(bool on);
 
-/* tuner.c */
+/* tuner.c  -- setting up the V4L tuner */
 bool configure_tuner(bool on);
 extern int tuner_fd;
 bool tuner_set_frequency(double mhz);
+uint16_t tuner_get_signal();
 bool tuner_search(bool forward);
 
-/* rds.c */
+/* rds.c -- RDS decoder */
 bool configure_rds(bool on);
 void rds_reset();
-
 unsigned short rds_get_pi();
 unsigned char rds_get_pty();
 const char * rds_get_pty_text();
 gchar * rds_get_ps();
 gchar * rds_get_rt();
 
+/* signal.c -- polling signal level */
+bool configure_signal(bool on);
+void signal_reset();
+
 #endif // FMRXD_H
diff --git a/radio.c b/radio.c
index 7b53fba..07c6ff8 100644
--- a/radio.c
+++ b/radio.c
@@ -34,13 +34,33 @@ void radio_start()
 	g_return_if_fail(!active);
 	g_debug("Starting radio");
 
-	configure_bt_muxer(true);
+	bool ok;
+
+	ok = configure_bt_muxer(true);
+	if (!ok) goto fail_start;
+
 	configure_mixer(true);
+	if (!ok) goto fail_start;
+
 	configure_tuner(true);
+	if (!ok) goto fail_start;
+
 	configure_capture(true);
+	if (!ok) goto fail_start;
+
+	// Not essential.
+	configure_signal(true);
 	configure_rds(true);
 
 	active = true;
+	return; // Success
+
+fail_start:
+	g_critical("Radio failed to start!");
+
+	// Try to force a stop
+	active = true;
+	radio_stop();
 }
 
 void radio_stop()
@@ -49,6 +69,7 @@ void radio_stop()
 	g_debug("Stopping radio");
 
 	configure_rds(false);
+	configure_signal(false);
 	configure_capture(false);
 	configure_tuner(false);
 	configure_mixer(false);
diff --git a/server.c b/server.c
index cfee65a..7b2cb53 100644
--- a/server.c
+++ b/server.c
@@ -72,6 +72,9 @@ static const char * introspect_data = {
 	"   </signal>\n"
 	"   <signal name=\"Stopped\">\n"
 	"   </signal>\n"
+	"   <signal name=\"SignalLevelChanged\">\n"
+	"     <arg type=\"q\" name=\"signal\" />\n"
+	"   </signal>\n"
 	"   <signal name=\"PiReceived\">\n"
 	"     <arg type=\"q\" name=\"pi\" />\n"
 	"   </signal>\n"
@@ -514,6 +517,15 @@ void server_notify_stopped()
 	dbus_message_unref(m);
 }
 
+void server_notify_signal(uint16_t signal)
+{
+	DBusMessage *m = dbus_message_new_signal(BUS_PATH, BUS_INTERFACE, "SignalLevelChanged");
+	g_return_if_fail(m != NULL);
+	dbus_message_append_args(m, DBUS_TYPE_UINT16, &signal, DBUS_TYPE_INVALID);
+	dbus_connection_send(bus, m, NULL);
+	dbus_message_unref(m);
+}
+
 void server_notify_pi(uint16_t pi)
 {
 	DBusMessage *m = dbus_message_new_signal(BUS_PATH, BUS_INTERFACE, "PiChanged");
diff --git a/signal.c b/signal.c
new file mode 100644
index 0000000..3618e34
--- /dev/null
+++ b/signal.c
@@ -0,0 +1,73 @@
+/*
+ *  fmrxd - a daemon to enable and multiplex access to the N950/N9 radio tuner
+ *  Copyright (C) 2011 Javier S. Pedro <maemo@javispedro.com>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "fmrxd.h"
+
+#include <glib.h>
+#include <linux/videodev2.h>
+
+static guint signal_timer_id = 0;
+static uint16_t last_signal_level = 0;
+
+static void signal_update()
+{
+	uint16_t new_signal_level = tuner_get_signal();
+	if (new_signal_level != last_signal_level) {
+		server_notify_signal(new_signal_level);
+		last_signal_level = new_signal_level;
+	}
+}
+
+static gboolean signal_poll(gpointer user_data)
+{
+	if (!signal_timer_id) return FALSE;
+	signal_update();
+	return TRUE;
+}
+
+static gboolean signal_refresh(gpointer user_data)
+{
+	if (!signal_timer_id) return FALSE;
+	signal_update();
+	return FALSE;
+}
+
+bool configure_signal(bool on)
+{
+	if (on) {
+		if (!signal_timer_id) {
+			signal_timer_id = g_timeout_add_seconds(SIGNAL_POLL_INTERVAL, signal_poll, NULL);
+		}
+	} else {
+		if (signal_timer_id) {
+			g_source_remove(signal_timer_id);
+			signal_timer_id = 0;
+		}
+	}
+
+	return true;
+}
+
+void signal_reset()
+{
+	last_signal_level = 0;
+	if (signal_timer_id) {
+		g_timeout_add(SIGNAL_REFRESH_DELAY, signal_refresh, NULL);
+	}
+}
diff --git a/tuner.c b/tuner.c
index 3d8e1ff..0f7b3f7 100644
--- a/tuner.c
+++ b/tuner.c
@@ -104,22 +104,6 @@ static unsigned long tuner_get_tuned_freq()
 	return v4l_to_hz(t_freq.frequency);
 }
 
-static uint16_t tuner_get_signal()
-{
-	struct v4l2_tuner t_tuner = {
-		.index = TUNER_DEVICE_ID
-	};
-
-	g_return_val_if_fail(tuner_is_open(), 0);
-
-	if (ioctl(tuner_fd, VIDIOC_G_TUNER, &t_tuner) < 0) {
-		g_warning("Failed to get signal level: %s", strerror(errno));
-		return 0;
-	}
-
-	return t_tuner.signal;
-}
-
 bool configure_tuner(bool on)
 {
 	if (on) {
@@ -182,6 +166,7 @@ bool tuner_set_frequency(double mhz)
 		g_message("Tuned to %.1f Mhz", mhz);
 		server_notify_tuned(mhz);
 		tuner_freq = hz;
+		signal_reset();
 		rds_reset();
 		return true;
 	}
@@ -189,6 +174,22 @@ bool tuner_set_frequency(double mhz)
 	return false;
 }
 
+uint16_t tuner_get_signal()
+{
+	struct v4l2_tuner t_tuner = {
+		.index = TUNER_DEVICE_ID
+	};
+
+	g_return_val_if_fail(tuner_is_open(), 0);
+
+	if (ioctl(tuner_fd, VIDIOC_G_TUNER, &t_tuner) < 0) {
+		g_warning("Failed to get signal level: %s", strerror(errno));
+		return 0;
+	}
+
+	return t_tuner.signal;
+}
+
 bool tuner_search(bool forward)
 {
 	struct v4l2_hw_freq_seek t_freq_seek = {
@@ -213,6 +214,7 @@ bool tuner_search(bool forward)
 	// Got new frequency, fire signals.
 	tuner_freq = hz;
 	server_notify_tuned(hz_to_mhz(hz));
+	signal_reset();
 	rds_reset();
 	return true;
 }