fix(radio): race condition on pulse buffer (#6634)

radio/src/hal/module_driver.h

@@ -22,6 +22,7 @@
 #pragma once
 
 #include <stdint.h>
+#include <stdbool.h>
 
 enum ChannelsProtocols {
   PROTOCOL_CHANNELS_UNINITIALIZED,
@@ -62,6 +63,9 @@ struct etx_proto_driver_t {
     // Some module settings may have been modified
     void (*onConfigChange)(void* ctx);
 
+    // Previous Frame already sent?
+    bool (*txCompleted)(void* ctx);
+
     // Module state mode has been modified
     // void (*onModeChange)(void* ctx, uint8_t old_mode, uint8_t new_mode);
 };

radio/src/hal/module_port.cpp

@@ -297,6 +297,22 @@ uint8_t modulePortGetModule(etx_module_state_t* st)
   return st - _module_states;
 }
 
+bool modulePortSerialTxCompleted(void* ctx)
+{
+  auto st = (etx_module_state_t*)ctx;
+  auto drv = modulePortGetSerialDrv(st->tx);
+  auto drv_ctx = modulePortGetCtx(st->tx);
+  return drv->txCompleted(drv_ctx);
+}
+
+bool modulePortTimerTxCompleted(void* ctx)
+{
+  auto st = (etx_module_state_t*)ctx;
+  auto drv = modulePortGetTimerDrv(st->tx);
+  auto drv_ctx = modulePortGetCtx(st->tx);
+  return drv->txCompleted(drv_ctx);
+}
+
 bool modulePortIsPortUsedByModule(uint8_t module, uint8_t port)
 {
   auto mod_st = modulePortGetState(module);

radio/src/hal/module_port.h

@@ -162,6 +162,9 @@ inline void* modulePortGetCtx(const etx_module_driver_t& d) {
   return d.ctx;
 }
 
+bool modulePortSerialTxCompleted(void* ctx);
+bool modulePortTimerTxCompleted(void* ctx);
+
 bool modulePortIsPortUsedByModule(uint8_t module, uint8_t port);
 bool modulePortIsPortUsed(uint8_t port);
 

radio/src/hal/serial_driver.h

@@ -22,6 +22,7 @@
 #pragma once
 
 #include <stdint.h>
+#include <stdbool.h>
 
 
 enum SerialEncoding {
@@ -79,7 +80,7 @@ typedef struct {
   void (*sendBuffer)(void* ctx, const uint8_t* data, uint32_t size);
 
   // Is TX phase completed
-  uint8_t (*txCompleted)(void* ctx);
+  bool (*txCompleted)(void* ctx);
   
   // Wait for last send operation to complete
   void (*waitForTxCompleted)(void* ctx);

radio/src/hal/timer_driver.h

@@ -22,6 +22,7 @@
 #pragma once
 
 #include <stdint.h>
+#include <stdbool.h>
 
 
 typedef struct {
@@ -33,4 +34,5 @@ typedef struct {
   void* (*init)(void* hw_def, const etx_timer_config_t* cfg);
   void (*deinit)(void* ctx);
   void (*send)(void* ctx, const etx_timer_config_t* cfg, const void* pulses, uint16_t length);
+  bool (*txCompleted)(void* ctx);
 } etx_timer_driver_t;

radio/src/pulses/afhds3.cpp

@@ -262,6 +262,8 @@ class ProtoState
 
    void applyConfigFromModel();
 
+   bool fifoFull() { return trsp.fifoFull(); }
+
   protected:
 
     void resetConfig(uint8_t version);
@@ -1159,6 +1161,13 @@ static void sendPulses(void* ctx, uint8_t* buffer, int16_t* channels,
   p_state->sendFrame();
 }
 
+static bool txCompleted(void* ctx)
+{
+  auto mod_st = (etx_module_state_t*)ctx;
+  auto p_state = (ProtoState*)mod_st->user_data;
+  return !p_state->fifoFull();
+}
+
 etx_proto_driver_t ProtoDriver = {
     .protocol = PROTOCOL_CHANNELS_AFHDS3,
     .init = initModule,
@@ -1167,6 +1176,7 @@ etx_proto_driver_t ProtoDriver = {
     .processData = processTelemetryData,
     .processFrame = nullptr,
     .onConfigChange = nullptr,
+    .txCompleted = txCompleted,
 };
 
 }  // namespace afhds3

radio/src/pulses/afhds3_transport.h

@@ -129,6 +129,7 @@ struct CommandFifo {
   }
 
   inline bool isEmpty() const { return (getIndex == setIndex); }
+  inline bool isFull() const { return nextIndex(setIndex) == getIndex; }
 
   inline void skip() { getIndex = nextIndex(getIndex); }
 
@@ -204,6 +205,8 @@ class Transport
 
   void sendBuffer();
 
+  bool fifoFull() { return fifo.isFull(); }
+
   /**
    * Process retransmissions
    * error: transport is in error state

radio/src/pulses/crossfire.cpp

@@ -452,4 +452,5 @@ const etx_proto_driver_t CrossfireDriver = {
   .processData = nullptr,
   .processFrame = crossfireProcessFrame,
   .onConfigChange = nullptr,
+  .txCompleted = modulePortSerialTxCompleted,
 };

radio/src/pulses/dsm2.cpp

@@ -298,6 +298,7 @@ const etx_proto_driver_t DSM2Driver = {
   .processData = nullptr,
   .processFrame = nullptr,
   .onConfigChange = dsm2ConfigChange,
+  .txCompleted = modulePortSerialTxCompleted,
 };
 
 const etx_proto_driver_t DSMPDriver = {
@@ -308,4 +309,5 @@ const etx_proto_driver_t DSMPDriver = {
   .processData = dsmpProcessData,
   .processFrame = nullptr,
   .onConfigChange = nullptr,
+  .txCompleted = modulePortSerialTxCompleted,
 };

radio/src/pulses/ghost.cpp

@@ -255,4 +255,5 @@ const etx_proto_driver_t GhostDriver = {
   .processData = ghostProcessData,
   .processFrame = nullptr,
   .onConfigChange = nullptr,
+  .txCompleted = modulePortSerialTxCompleted,
 };

radio/src/pulses/multi.cpp

@@ -288,6 +288,7 @@ const etx_proto_driver_t MultiDriver = {
   .processData = multiProcessData,
   .processFrame = nullptr,
   .onConfigChange = nullptr,
+  .txCompleted = modulePortSerialTxCompleted,
 };
 
 static void sendChannels(uint8_t*& p_buf, uint8_t module)

radio/src/pulses/ppm.cpp

@@ -244,4 +244,5 @@ const etx_proto_driver_t PpmDriver = {
   .processData = ppmProcessTelemetryData,
   .processFrame = nullptr,
   .onConfigChange = ppmOnConfigChange,
+  .txCompleted = modulePortTimerTxCompleted,
 };

radio/src/pulses/pulses.cpp

@@ -551,6 +551,9 @@ void pulsesSendNextFrame(uint8_t module)
       state.settings_updated = 0;
     }
 
+    // if previous frame not completed, skip this one
+    if (!drv->txCompleted(ctx)) return;
+
     uint8_t channelStart = g_model.moduleData[module].channelsStart;
     int16_t* channels = &channelOutputs[channelStart];
     uint8_t nChannels = 16;  // TODO: MAX_CHANNELS - channelsStart

radio/src/pulses/pxx1.cpp

@@ -416,4 +416,5 @@ const etx_proto_driver_t Pxx1Driver = {
   .processData = pxx1ProcessData,
   .processFrame = nullptr,
   .onConfigChange = nullptr,
+  .txCompleted = modulePortSerialTxCompleted,
 };

radio/src/pulses/pxx2.cpp

@@ -833,7 +833,6 @@ static void pxx2ProcessData(void* ctx, uint8_t data, uint8_t* buffer, uint8_t* l
 }
 
 #include "hal/module_driver.h"
-// #include "extmodule_serial_driver.h"
 
 const etx_proto_driver_t Pxx2Driver = {
   .protocol = PROTOCOL_CHANNELS_PXX2,
@@ -843,4 +842,5 @@ const etx_proto_driver_t Pxx2Driver = {
   .processData = pxx2ProcessData,
   .processFrame = nullptr,
   .onConfigChange = nullptr,
+  .txCompleted = modulePortSerialTxCompleted,
 };

radio/src/pulses/sbus.cpp

@@ -217,4 +217,5 @@ const etx_proto_driver_t SBusDriver = {
   .processData = sbusProcessTelemetryData,
   .processFrame = nullptr,
   .onConfigChange = sbusOnConfigChange,
+  .txCompleted = modulePortSerialTxCompleted,
 };

radio/src/targets/common/arm/stm32/stm32_pulse_driver.cpp

@@ -274,6 +274,13 @@ static void set_oc_mode(const stm32_pulse_timer_t* tim, uint32_t ocmode)
   LL_TIM_OC_SetMode(tim->TIMx, channel, ocmode);
 }
 
+bool stm32_pulse_is_completed(const stm32_pulse_timer_t* tim)
+{
+  uint32_t channel = _get_base_channel(tim->TIM_Channel);
+  return !LL_TIM_IsEnabledCounter(tim->TIMx) ||
+         LL_TIM_OC_GetMode(tim->TIMx, channel) == LL_TIM_OCMODE_FORCED_INACTIVE;
+}
+
 void stm32_pulse_wait_for_completed(const stm32_pulse_timer_t* tim)
 {
   uint32_t channel = _get_base_channel(tim->TIM_Channel);

radio/src/targets/common/arm/stm32/stm32_pulse_driver.h

@@ -69,6 +69,7 @@ void stm32_pulse_set_cmp_val(const stm32_pulse_timer_t* tim, uint32_t cmp_val);
 void stm32_pulse_start(const stm32_pulse_timer_t* tim);
 void stm32_pulse_stop(const stm32_pulse_timer_t* tim);
 
+bool stm32_pulse_is_completed(const stm32_pulse_timer_t* tim);
 void stm32_pulse_wait_for_completed(const stm32_pulse_timer_t* tim);
 
 // return true if it could be disabled without interrupting a pulse train, false otherwise

radio/src/targets/common/arm/stm32/stm32_serial_driver.cpp

@@ -383,7 +383,7 @@ static void stm32_serial_send_buffer(void* ctx, const uint8_t* data, uint32_t si
   }
 }
 
-static uint8_t stm32_serial_tx_completed(void* ctx)
+static bool stm32_serial_tx_completed(void* ctx)
 {
   auto st = (stm32_serial_state*)ctx;
   if (!st) return 1;

radio/src/targets/common/arm/stm32/stm32_softserial_driver.cpp

@@ -494,6 +494,13 @@ static void stm32_softserial_tx_send_buffer(void* ctx, const uint8_t* data, uint
   stm32_pulse_start_dma_req(timer, pulses, length, ocmode, cmp_val);
 }
 
+static bool stm32_softserial_tx_completed(void* ctx)
+{
+  auto port = (const stm32_softserial_tx_port*)ctx;
+  auto timer = port->tim;
+  return stm32_pulse_is_completed(timer);
+}
+
 void stm32_softserial_set_polarity(void* ctx, uint8_t polarity)
 {
   auto port = (const stm32_softserial_tx_port*)ctx;
@@ -507,7 +514,7 @@ const etx_serial_driver_t STM32SoftSerialTxDriver = {
   .deinit = stm32_softserial_tx_deinit,
   .sendByte = stm32_softserial_tx_send_byte,
   .sendBuffer = stm32_softserial_tx_send_buffer,
-  .txCompleted = nullptr,
+  .txCompleted = stm32_softserial_tx_completed,
   .waitForTxCompleted = stm32_softserial_tx_wait,
   .enableRx = nullptr, // TODO: combine with EXTI / Timer implementation? (S.PORT INV RX)
   .getByte = nullptr,

radio/src/targets/simu/module_drivers.cpp

@@ -86,6 +86,7 @@ static void deinit(void* ctx)
 
 static void sendByte(void*, uint8_t) {}
 static void sendBuffer(void*, const uint8_t*, uint32_t) {}
+static bool txCompleted(void*) { return true; }
 static void waitForTxCompleted(void*) {}
 static int getByte(void*,uint8_t*) { return -1; }
 
@@ -94,7 +95,7 @@ const etx_serial_driver_t _fakeSerialDriver = {
     .deinit = deinit,
     .sendByte = sendByte,
     .sendBuffer = sendBuffer,
-    .txCompleted = nullptr,
+    .txCompleted = txCompleted,
     .waitForTxCompleted = waitForTxCompleted,
     .enableRx = nullptr,
     .getByte = getByte,

radio/src/targets/simu/simpgmspace.cpp

@@ -381,6 +381,7 @@ static void* null_drv_init(void* hw_def, const etx_serial_init* dev) { return nu
 static void null_drv_deinit(void* ctx) { }
 static void null_drv_send_byte(void* ctx, uint8_t b) { }
 static void null_drv_send_buffer(void* ctx, const uint8_t* b, uint32_t l) { }
+static bool null_drv_tx_completed(void* ctx) { return true; }
 static int null_drv_get_byte(void* ctx, uint8_t* b) { return 0; }
 static void null_drv_set_baudrate(void* ctx, uint32_t baudrate) { }
 
@@ -389,7 +390,7 @@ const etx_serial_driver_t null_drv = {
   .deinit = null_drv_deinit,
   .sendByte = null_drv_send_byte,
   .sendBuffer = null_drv_send_buffer,
-  .txCompleted = nullptr,
+  .txCompleted = null_drv_tx_completed,
   .waitForTxCompleted = nullptr,
   .enableRx = nullptr,
   .getByte = null_drv_get_byte,