TX timeout issue fix

In case of catastrophic bus failure at radio end, we shouldn't reset the chip
as it will cause the chip to hang and then burst out interrupts in a fury resulting
in an ISR queue overflow.
rather than that we gracefully accept the failure and set the radio to sleep and
set the state to idle. In addition to that we inform the upper layers about the
failure.

A little touch up to the FHSS case, was actually a leftover from the previous PR.
We don't use FHSS mode, that was why we didn't catch in the testing.

Author: Hasnain Virk

SX1272/SX1272_LoRaRadio.cpp

@@ -833,7 +833,7 @@ void SX1272_LoRaRadio::transmit(uint32_t timeout)
                                   RFLR_DIOMAPPING1_DIO0_MASK &
                                   RFLR_DIOMAPPING1_DIO2_MASK) |
                                   RFLR_DIOMAPPING1_DIO0_01 |
-                                  RFLR_DIOMAPPING1_DIO2_00);
+                                  RFLR_DIOMAPPING1_DIO2_01);
             } else {
                 write_to_register(REG_LR_IRQFLAGSMASK,
                                   RFLR_IRQFLAGS_RXTIMEOUT |
@@ -854,7 +854,8 @@ void SX1272_LoRaRadio::transmit(uint32_t timeout)
     }
 
     _rf_settings.state = RF_TX_RUNNING;
-    tx_timeout_timer.attach_us(callback(this, &SX1272_LoRaRadio::timeout_irq_isr), timeout*1e3);
+    tx_timeout_timer.attach_us(callback(this, &SX1272_LoRaRadio::timeout_irq_isr),
+                               timeout * 1000);
     set_operation_mode(RF_OPMODE_TRANSMITTER);
 }
 
@@ -2082,69 +2083,31 @@ void SX1272_LoRaRadio::handle_dio5_irq()
     }
 }
 
-
 void SX1272_LoRaRadio::handle_timeout_irq()
 {
-    switch(_rf_settings.state )
-     {
-     case RF_RX_RUNNING:
-         if( _rf_settings.modem == MODEM_FSK ) {
-             _rf_settings.fsk_packet_handler.preamble_detected = 0;
-             _rf_settings.fsk_packet_handler.sync_word_detected = 0;
-             _rf_settings.fsk_packet_handler.nb_bytes = 0;
-             _rf_settings.fsk_packet_handler.size = 0;
-
-             // Clear Irqs
-             write_to_register(REG_IRQFLAGS1, RF_IRQFLAGS1_RSSI |
-                                         RF_IRQFLAGS1_PREAMBLEDETECT |
-                                         RF_IRQFLAGS1_SYNCADDRESSMATCH);
-             write_to_register( REG_IRQFLAGS2, RF_IRQFLAGS2_FIFOOVERRUN);
-
-             if( _rf_settings.fsk.rx_continuous == true )
-             {
-                 // Continuous mode restart Rx chain
-                 write_to_register( REG_RXCONFIG, read_register(REG_RXCONFIG) |
-                                    RF_RXCONFIG_RESTARTRXWITHOUTPLLLOCK);
-             }
-             else
-             {
-                 _rf_settings.state = RF_IDLE;
-             }
-         }
-
-         if((_radio_events != NULL) && (_radio_events->rx_timeout)) {
-             _radio_events->rx_timeout();
-         }
-
-         break;
-
-     case RF_TX_RUNNING:
-         // Tx timeout shouldn't happen.
-         // But it has been observed that when it happens it is a result of a
-         // corrupted SPI transfer
-         // The workaround is to put the radio in a known state.
-         // Thus, we re-initialize it.
-
-         // Reset the radio
-         radio_reset( );
-
-         // Initialize radio default values
-         set_operation_mode( RF_OPMODE_SLEEP );
-
-         setup_registers();
-
-         set_modem(MODEM_FSK);
-
-         // Restore previous network type setting.
-         set_public_network(_rf_settings.lora.public_network);
-
-         _rf_settings.state = RF_IDLE;
-         if( ( _radio_events != NULL ) && ( _radio_events->tx_timeout ) )
-         {
-             _radio_events->tx_timeout( );
-         }
-         break;
-     default:
-         break;
-     }
+    tx_timeout_timer.detach();
+
+    if (_rf_settings.state == RF_TX_RUNNING) {
+        // Tx timeout shouldn't happen.
+        // But it has been observed that when it happens it is a result of a
+        // corrupted SPI transfer
+        // The workaround is to put the radio in a known state.
+        // Thus, we re-initialize it.
+
+        // Initialize radio default values
+        set_operation_mode(RF_OPMODE_SLEEP);
+
+        setup_registers();
+
+        set_modem(MODEM_FSK);
+
+        // Restore previous network type setting.
+        set_public_network(_rf_settings.lora.public_network);
+
+        _rf_settings.state = RF_IDLE;
+
+        if ((_radio_events != NULL) && (_radio_events->tx_timeout)) {
+            _radio_events->tx_timeout();
+        }
+    }
 }

SX1276/SX1276_LoRaRadio.cpp

@@ -1562,7 +1562,7 @@ void SX1276_LoRaRadio::transmit(uint32_t timeout)
                                   RFLR_DIOMAPPING1_DIO0_MASK &
                                   RFLR_DIOMAPPING1_DIO2_MASK) |
                                   RFLR_DIOMAPPING1_DIO0_01 |
-                                  RFLR_DIOMAPPING1_DIO2_00);
+                                  RFLR_DIOMAPPING1_DIO2_01);
             } else {
                 write_to_register(REG_LR_IRQFLAGSMASK,
                                   RFLR_IRQFLAGS_RXTIMEOUT |
@@ -1583,8 +1583,10 @@ void SX1276_LoRaRadio::transmit(uint32_t timeout)
     }
 
     _rf_settings.state = RF_TX_RUNNING;
+
     tx_timeout_timer.attach_us(callback(this,
                                &SX1276_LoRaRadio::timeout_irq_isr), timeout * 1000);
+
     set_operation_mode(RF_OPMODE_TRANSMITTER);
 }
 
@@ -2242,19 +2244,17 @@ void SX1276_LoRaRadio::handle_dio5_irq()
     }
 }
 
-
 void SX1276_LoRaRadio::handle_timeout_irq()
 {
+    tx_timeout_timer.detach();
+
     if (_rf_settings.state == RF_TX_RUNNING) {
         // Tx timeout shouldn't happen.
         // But it has been observed that when it happens it is a result of a
         // corrupted SPI transfer
         // The workaround is to put the radio in a known state.
         // Thus, we re-initialize it.
 
-        // Reset the radio
-        radio_reset();
-
         // Initialize radio default values
         set_operation_mode(RF_OPMODE_SLEEP);
 
@@ -2266,10 +2266,10 @@ void SX1276_LoRaRadio::handle_timeout_irq()
         set_public_network(_rf_settings.lora.public_network);
 
         _rf_settings.state = RF_IDLE;
+
         if ((_radio_events != NULL) && (_radio_events->tx_timeout)) {
             _radio_events->tx_timeout();
         }
-
     }
 }
 // EOF