AP_HAL_Linux: added tonealarm support for raspilot

libraries/AP_HAL_Linux/ToneAlarmDriver.cpp

@@ -13,6 +13,11 @@
 
 using namespace Linux;
 
+#if CONFIG_HAL_BOARD_SUBTYPE == HAL_BOARD_SUBTYPE_LINUX_RASPILOT
+#include "GPIO.h"
+#define RASPILOT_TONE_PIN RPI_GPIO_18
+#endif
+
 extern const AP_HAL::HAL& hal;
 static uint16_t notes[] = { 0,
 NOTE_C4, NOTE_CS4, NOTE_D4, NOTE_DS4, NOTE_E4, NOTE_F4, NOTE_FS4, NOTE_G4, NOTE_GS4, NOTE_A4, NOTE_AS4, NOTE_B4,
@@ -50,10 +55,16 @@ ToneAlarm::ToneAlarm()
 bool ToneAlarm::init()
 {
     tune_num = 0;                    //play startup tune
+
+#if CONFIG_HAL_BOARD_SUBTYPE == HAL_BOARD_SUBTYPE_LINUX_RASPILOT
+    hal.gpio->pinMode(RASPILOT_TONE_PIN, HAL_GPIO_ALT, 5);
+#else
     if((period_fd == -1) || (duty_fd == -1) || (run_fd == -1)){
         hal.console->printf("ToneAlarm: Error!! please check if PWM overlays are loaded correctly");
         return false;
     }
+#endif
+
     return true;
 }
 
@@ -69,7 +80,11 @@ bool ToneAlarm::is_tune_comp()
 
 void ToneAlarm::stop()
 {
+#if CONFIG_HAL_BOARD_SUBTYPE == HAL_BOARD_SUBTYPE_LINUX_RASPILOT
+    hal.gpio->setPWMDuty(RASPILOT_TONE_PIN, 0);
+#else
     dprintf(run_fd,"0");
+#endif
 }
 
 bool ToneAlarm::play()
@@ -80,10 +95,15 @@ bool ToneAlarm::play()
         return true;
     }
     if(cur_note != 0){
+#if CONFIG_HAL_BOARD_SUBTYPE == HAL_BOARD_SUBTYPE_LINUX_RASPILOT
+        hal.gpio->setPWMPeriod(RASPILOT_TONE_PIN, 1000000/cur_note);
+        hal.gpio->setPWMDuty(RASPILOT_TONE_PIN, 50);
+#else
         dprintf(run_fd,"0");
         dprintf(period_fd,"%u",1000000000/cur_note);
         dprintf(duty_fd,"%u",500000000/cur_note);
         dprintf(run_fd,"1");
+#endif
         cur_note =0;
         prev_time = cur_time;
     }
@@ -189,7 +209,6 @@ bool ToneAlarm::set_note(){
         cur_note = 0;
         return true;
     }
-    
 }
 
 bool ToneAlarm::init_tune(){