[simu] Refactor simu startup and shutdown handling (for 2.3 branch):

* Use pwrCheck() as primary control point for shutdown, centralizes thread control in simpgmspace module;
 * Remove main_thread_running in favor of separate variables for startup mode and shutdown flag;
 * Don't start a thread for ARM startup, just run simuMain() directly (the thread just exits anyway);
 * Refactor SIMU_SLEEP() macro, and remove all unnecessary uses of it, also remove SIMU_SLEEP_NORET;
 * Add startType param to opentxStart() to control splash and startup checks;
 * Fixes backlight never turning off in simulator with "SWITCH" power button type (pwrPressed() was always true);
 * Fixes simu shutdown when model checklist is displayed at startup;
 * Adds stubs to possibly simulate a "soft" power button in the future.

radio/src/targets/simu/simpgmspace.cpp

@@ -40,10 +40,12 @@ uint8_t portb, portc, porth=0, dummyport;
 uint16_t dummyport16;
 int g_snapshot_idx = 0;
 
-pthread_t main_thread_pid;
-uint8_t main_thread_running = 0;
+uint8_t simu_start_mode = 0;
 char * main_thread_error = NULL;
 
+bool simu_shutdown = false;
+bool simu_running = false;
+
 #if defined(STM32)
 uint32_t Peri1_frequency, Peri2_frequency;
 GPIO_TypeDef gpioa, gpiob, gpioc, gpiod, gpioe, gpiof, gpiog, gpioh, gpioi, gpioj;
@@ -132,6 +134,13 @@ void simuInit()
   RCC->CSR = 0;
 #endif
 
+  // set power button to "not pressed"
+#if defined(PWR_SWITCH_GPIO)  // STM32
+  GPIO_SetBits(PWR_SWITCH_GPIO, PWR_SWITCH_GPIO_PIN);
+#elif defined(PIO_PC17)       // AT91SAM3
+  PIOC->PIO_PDSR &= ~PIO_PC17;
+#endif
+
   for (int i = 0; i <= 17; i++) {
     simuSetSwitch(i, 0);
     simuSetKey(i, false);  // a little dirty, but setting keys that don't exist is perfectly OK here
@@ -315,13 +324,14 @@ void simuSetSwitch(uint8_t swtch, int8_t state)
 
 void StartSimu(bool tests, const char * sdPath, const char * settingsPath)
 {
-  if (main_thread_running)
+  if (simu_running)
     return;
 
   s_current_protocol[0] = 255;
   menuLevel = 0;
 
-  main_thread_running = (tests ? 1 : 2); // TODO rename to simu_run_mode with #define
+  simu_start_mode = (tests ? 0 : 0x02 /* OPENTX_START_NO_CHECKS */);
+  simu_shutdown = false;
 
   simuFatfsSetPaths(sdPath, settingsPath);
 
@@ -350,7 +360,9 @@ void StartSimu(bool tests, const char * sdPath, const char * settingsPath)
   try {
 #endif
 
-  pthread_create(&main_thread_pid, NULL, &simuMain, NULL);
+  simuMain();
+
+  simu_running = true;
 
 #if defined(SIMU_EXCEPTIONS)
   }
@@ -361,14 +373,15 @@ void StartSimu(bool tests, const char * sdPath, const char * settingsPath)
 
 void StopSimu()
 {
-  if (!main_thread_running)
+  if (!simu_running)
     return;
 
-  main_thread_running = 0;
+  simu_shutdown = true;
 
   pthread_join(mixerTaskId, NULL);
   pthread_join(menusTaskId, NULL);
-  pthread_join(main_thread_pid, NULL);
+
+  simu_running = false;
 }
 
 struct SimulatorAudio {
@@ -380,6 +393,21 @@ struct SimulatorAudio {
   pthread_t threadPid;
 } simuAudio;
 
+bool simuIsRunning()
+{
+  return simu_running;
+}
+
+bool simuSleep(uint32_t ms)
+{
+  for (uint32_t i = 0; i < ms; ++i){
+    if (simu_shutdown || !simu_running)
+      return false;
+    sleep(1);
+  }
+  return true;
+}
+
 void audioConsumeCurrentBuffer()
 {
 }
@@ -572,16 +600,25 @@ int lcdRestoreBackupBuffer()
   return 1;
 }
 
+uint32_t pwrCheck()
+{
+  // TODO: ability to simulate shutdown warning for a "soft" simulator restart
+  return simu_shutdown ? e_power_off : e_power_on;
+}
 
 void pwrOff()
 {
 }
+
 uint32_t pwrPressed()
 {
-#if defined(PWR_BUTTON_PRESS)
-  return false;
+  // TODO: simulate power button
+#if defined(PWR_SWITCH_GPIO)  // STM32
+  return GPIO_ReadInputDataBit(PWR_SWITCH_GPIO, PWR_SWITCH_GPIO_PIN) == Bit_RESET;
+#elif defined(PIO_PC17)       // AT91SAM3
+  return PIOC->PIO_PDSR & PIO_PC17;
 #else
-  return true;
+  return false;
 #endif
 }
 
@@ -648,9 +685,9 @@ FlagStatus RCC_GetFlagStatus(uint8_t RCC_FLAG) { return SET; }
 ErrorStatus RTC_WaitForSynchro(void) { return SUCCESS; }
 void unlockFlash() { }
 void lockFlash() { }
-void flashWrite(uint32_t *address, uint32_t *buffer) { SIMU_SLEEP(100); }
+void flashWrite(uint32_t *address, uint32_t *buffer) { simuSleep(100); }
 uint32_t isBootloaderStart(const uint8_t * block) { return 1; }
-#endif // defined(PCBTARANIS)
+#endif // defined(STM32)
 
 #if defined(PCBHORUS)
 void LCD_ControlLight(uint16_t dutyCycle) { }