From 06472861ce874da957eca0a83e28171af7052ef0 Mon Sep 17 00:00:00 2001
From: jgoppert <james.goppert@gmail.com>
Date: Sat, 24 Oct 2015 10:11:03 -0400
Subject: [PATCH] Added buzzer circuit breaker.

---
 src/drivers/stm32/tone_alarm/tone_alarm.cpp   | 20 ++++++++++++++++++-
 .../systemlib/circuit_breaker_params.c        | 15 +++++++++++++-
 2 files changed, 33 insertions(+), 2 deletions(-)

diff --git a/src/drivers/stm32/tone_alarm/tone_alarm.cpp b/src/drivers/stm32/tone_alarm/tone_alarm.cpp
index 55b36f8bb4..1a54e11809 100644
--- a/src/drivers/stm32/tone_alarm/tone_alarm.cpp
+++ b/src/drivers/stm32/tone_alarm/tone_alarm.cpp
@@ -116,6 +116,7 @@
 #include <stm32_tim.h>
 
 #include <systemlib/err.h>
+#include <systemlib/circuit_breaker.h>
 
 /* Check that tone alarm and HRT timers are different */
 #if defined(TONE_ALARM_TIMER)  && defined(HRT_TIMER)
@@ -273,6 +274,8 @@
 # define rDMAR    	REG(STM32_GTIM_DMAR_OFFSET)
 #endif
 
+#define CBRK_BUZZER_KEY 782097
+
 class ToneAlarm : public device::CDev
 {
 public:
@@ -288,6 +291,12 @@ public:
 		return _tune_names[tune];
 	}
 
+	enum {
+		CBRK_OFF = 0,
+		CBRK_ON,
+		CBRK_UNINIT
+	};
+
 private:
 	static const unsigned	_tune_max = 1024 * 8; // be reasonable about user tunes
 	const char		 *_default_tunes[TONE_NUMBER_OF_TUNES];
@@ -307,6 +316,7 @@ private:
 	unsigned		_octave;
 	unsigned		_silence_length; // if nonzero, silence before next note
 	bool			_repeat;	// if true, tune restarts at end
+	int				_cbrk;	//if true, no audio output
 
 	hrt_call		_note_call;	// HRT callout for note completion
 
@@ -375,7 +385,8 @@ ToneAlarm::ToneAlarm() :
 	_default_tune_number(0),
 	_user_tune(nullptr),
 	_tune(nullptr),
-	_next(nullptr)
+	_next(nullptr),
+	_cbrk(CBRK_UNINIT)
 {
 	// enable debug() calls
 	//_debug_enabled = true;
@@ -537,6 +548,13 @@ ToneAlarm::rest_duration(unsigned rest_length, unsigned dots)
 void
 ToneAlarm::start_note(unsigned note)
 {
+	// check if circuit breaker is enabled
+	if (_cbrk == CBRK_UNINIT) {
+		_cbrk = circuit_breaker_enabled("CBRK_BUZZER", CBRK_BUZZER_KEY);
+	}
+
+	if (_cbrk != CBRK_OFF) { return; }
+
 	// compute the divisor
 	unsigned divisor = note_to_divisor(note);
 
diff --git a/src/modules/systemlib/circuit_breaker_params.c b/src/modules/systemlib/circuit_breaker_params.c
index 36b35246db..003b73bb62 100644
--- a/src/modules/systemlib/circuit_breaker_params.c
+++ b/src/modules/systemlib/circuit_breaker_params.c
@@ -133,4 +133,17 @@ PARAM_DEFINE_INT32(CBRK_ENGINEFAIL, 284953);
  * @max 240024
  * @group Circuit Breaker
  */
-PARAM_DEFINE_INT32(CBRK_GPSFAIL, 240024);
\ No newline at end of file
+PARAM_DEFINE_INT32(CBRK_GPSFAIL, 240024);
+
+/**
+ * Circuit breaker for disabling buzzer
+ *
+ * Setting this parameter to 782097 will disable the buzzer audio notification.
+ *
+ * WARNING: ENABLING THIS CIRCUIT BREAKER IS AT OWN RISK
+ *
+ * @min 0
+ * @max 782097
+ * @group Circuit Breaker
+ */
+PARAM_DEFINE_INT32(CBRK_BUZZER, 0);