Added functionality to pass custom parameter to HardwareTimer callback

cores/arduino/HardwareTimer.cpp

@@ -850,8 +850,9 @@ void HardwareTimer::setInterruptPriority(uint32_t preemptPriority, uint32_t subP
   * @param  callback: interrupt callback
   * @retval None
   */
-void HardwareTimer::attachInterrupt(void (*callback)(HardwareTimer *))
+void HardwareTimer::attachInterrupt(void (*callback)(HardwareTimer *), void *arg)
 {
+  args[0] = arg;
   if (callbacks[0] != NULL) {
     // Callback previously configured : do not clear neither enable IT, it is just a change of callback
     callbacks[0] = callback;
@@ -875,6 +876,7 @@ void HardwareTimer::detachInterrupt()
   // Disable update interrupt and clear callback
   __HAL_TIM_DISABLE_IT(&(_timerObj.handle), TIM_IT_UPDATE); // disables the interrupt call to save cpu cycles for useless context switching
   callbacks[0] = NULL;
+  args[0] = NULL;
 }
 
 /**
@@ -883,7 +885,7 @@ void HardwareTimer::detachInterrupt()
   * @param  callback: interrupt callback
   * @retval None
   */
-void HardwareTimer::attachInterrupt(uint32_t channel, void (*callback)(HardwareTimer *))
+void HardwareTimer::attachInterrupt(uint32_t channel, void (*callback)(HardwareTimer *), void *arg)
 {
   int interrupt = getIT(channel);
   if (interrupt == -1) {
@@ -893,7 +895,7 @@ void HardwareTimer::attachInterrupt(uint32_t channel, void (*callback)(HardwareT
   if ((channel == 0) || (channel > (TIMER_CHANNELS + 1))) {
     Error_Handler();  // only channel 1..4 have an interrupt
   }
-
+  args[channel] = arg;
   if (callbacks[channel] != NULL) {
     // Callback previously configured : do not clear neither enable IT, it is just a change of callback
     callbacks[channel] = callback;
@@ -927,6 +929,29 @@ void HardwareTimer::detachInterrupt(uint32_t channel)
   // Disable interrupt corresponding to channel and clear callback
   __HAL_TIM_DISABLE_IT(&(_timerObj.handle), interrupt);
   callbacks[channel] = NULL;
+  args[channel] = NULL;
+}
+
+/**
+ * @brief  Get argument attached to (rollover) event.
+ * @retval Associated pointer to attached argument or NULL if not set.
+ */
+void *HardwareTimer::getArg()
+{
+  return args[0];
+}
+
+/**
+ * @brief Get argument attached to Capture/Compare event.
+ * @param  channel: arduino channel [1..4]
+ * @retval Associated pointer to attached argument or NULL if not set.
+ */
+void *HardwareTimer::getArg(uint32_t channel)
+{
+  if ((channel == 0) || (channel > (TIMER_CHANNELS + 1))) {
+    Error_Handler();  // only channel 1..4 have an interrupt
+  }
+  return args[channel];
 }
 
 /**

cores/arduino/HardwareTimer.h

@@ -126,13 +126,15 @@ class HardwareTimer {
     void setInterruptPriority(uint32_t preemptPriority, uint32_t subPriority); // set interrupt priority
 
     //Add interrupt to period update
-    void attachInterrupt(void (*handler)(HardwareTimer *)); // Attach interrupt callback which will be called upon update event (timer rollover)
+    void attachInterrupt(void (*handler)(HardwareTimer *), void *arg = NULL); // Attach interrupt callback which will be called upon update event (timer rollover)
     void detachInterrupt();  // remove interrupt callback which was attached to update event
     bool hasInterrupt();  //returns true if a timer rollover interrupt has already been set
+    void *getArg(); // Getter for attached argument to event (timer rollover)
     //Add interrupt to capture/compare channel
-    void attachInterrupt(uint32_t channel, void (*handler)(HardwareTimer *)); // Attach interrupt callback which will be called upon compare match event of specified channel
+    void attachInterrupt(uint32_t channel, void (*handler)(HardwareTimer *), void *arg = NULL); // Attach interrupt callback which will be called upon compare match event of specified channel
     void detachInterrupt(uint32_t channel);  // remove interrupt callback which was attached to compare match event of specified channel
     bool hasInterrupt(uint32_t channel);  //returns true if an interrupt has already been set on the channel compare match
+    void *getArg(uint32_t channel); // Getter for attached argument to compare match event of specified channel
 
     void timerHandleDeinit();  // Timer deinitialization
 
@@ -152,6 +154,8 @@ class HardwareTimer {
     TimerModes_t  _ChannelMode[TIMER_CHANNELS];
     timerObj_t _timerObj;
     void (*callbacks[1 + TIMER_CHANNELS])(HardwareTimer *); //Callbacks: 0 for update, 1-4 for channels. (channel5/channel6, if any, doesn't have interrupt)
+    void *args[1 + TIMER_CHANNELS];
+
     int getChannel(uint32_t channel);
     int getLLChannel(uint32_t channel);
     int getIT(uint32_t channel);