From 0b936e57740cd76aa3643d0adcc5d741978302c0 Mon Sep 17 00:00:00 2001
From: Erik tideman <erik.tideman@gmail.com>
Date: Sun, 26 Jan 2020 14:32:30 +0100
Subject: [PATCH 1/8] Added functionality to pass custom parameter to
 HardwareTimer callback

---
 cores/arduino/HardwareTimer.cpp | 16 +++++++++++++---
 cores/arduino/HardwareTimer.h   |  8 ++++++--
 2 files changed, 19 insertions(+), 5 deletions(-)

diff --git a/cores/arduino/HardwareTimer.cpp b/cores/arduino/HardwareTimer.cpp
index 7477eea9de..97591be69b 100644
--- a/cores/arduino/HardwareTimer.cpp
+++ b/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 +929,14 @@ 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;
+}
+
+void* HardwareTimer::getArg(uint32_t channel){
+  if (channel > (TIMER_CHANNELS + 1)) {
+    Error_Handler();
+  }
+  return args[channel];
 }
 
 /**
diff --git a/cores/arduino/HardwareTimer.h b/cores/arduino/HardwareTimer.h
index c02e47e587..789f7dd76d 100644
--- a/cores/arduino/HardwareTimer.h
+++ b/cores/arduino/HardwareTimer.h
@@ -126,14 +126,16 @@ 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
     //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 = 0);
+
     void timerHandleDeinit();  // Timer deinitialization
 
     // Refresh() is usefull while timer is running after some registers update
@@ -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);

From 015ca5ae2e32a3354a86d1f837fd16ffabf6d92b Mon Sep 17 00:00:00 2001
From: Erik tideman <erik.tideman@gmail.com>
Date: Mon, 27 Jan 2020 19:36:20 +0100
Subject: [PATCH 2/8] Fixed comments from review in HardwareTimer

---
 cores/arduino/HardwareTimer.cpp | 21 ++++++++++++++++++---
 cores/arduino/HardwareTimer.h   |  4 ++--
 2 files changed, 20 insertions(+), 5 deletions(-)

diff --git a/cores/arduino/HardwareTimer.cpp b/cores/arduino/HardwareTimer.cpp
index 97591be69b..8200fd7afc 100644
--- a/cores/arduino/HardwareTimer.cpp
+++ b/cores/arduino/HardwareTimer.cpp
@@ -932,9 +932,24 @@ void HardwareTimer::detachInterrupt(uint32_t channel)
   args[channel] = NULL;
 }
 
-void* HardwareTimer::getArg(uint32_t channel){
-  if (channel > (TIMER_CHANNELS + 1)) {
-    Error_Handler();
+/**
+ * @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];
 }
diff --git a/cores/arduino/HardwareTimer.h b/cores/arduino/HardwareTimer.h
index 789f7dd76d..d8a33157ad 100644
--- a/cores/arduino/HardwareTimer.h
+++ b/cores/arduino/HardwareTimer.h
@@ -129,12 +129,12 @@ class HardwareTimer {
     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 *), 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 = 0);
+    void *getArg(uint32_t channel); // Getter for attached argument to compare match event of specified channel
 
     void timerHandleDeinit();  // Timer deinitialization
 

From e34baac876ad67bfb1cea24a22e4cdb07a4b15cb Mon Sep 17 00:00:00 2001
From: Erik Tideman <erik.tideman@gmail.com>
Date: Tue, 28 Jan 2020 19:14:08 +0100
Subject: [PATCH 3/8] added comments for new param in attachInterrupts

---
 cores/arduino/HardwareTimer.cpp | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/cores/arduino/HardwareTimer.cpp b/cores/arduino/HardwareTimer.cpp
index 8200fd7afc..8c9aed52b7 100644
--- a/cores/arduino/HardwareTimer.cpp
+++ b/cores/arduino/HardwareTimer.cpp
@@ -848,6 +848,7 @@ void HardwareTimer::setInterruptPriority(uint32_t preemptPriority, uint32_t subP
 /**
   * @brief  Attach interrupt callback on update (rollover) event
   * @param  callback: interrupt callback
+  * @param  arg: pointer to optional argument to associate with interrupt
   * @retval None
   */
 void HardwareTimer::attachInterrupt(void (*callback)(HardwareTimer *), void *arg)
@@ -883,6 +884,7 @@ void HardwareTimer::detachInterrupt()
   * @brief  Attach interrupt callback on Capture/Compare event
   * @param  channel: Arduino channel [1..4]
   * @param  callback: interrupt callback
+  * @param  arg: pointer to optional argument to associate with interrupt
   * @retval None
   */
 void HardwareTimer::attachInterrupt(uint32_t channel, void (*callback)(HardwareTimer *), void *arg)

From c2b6251e275e61e35f922a51b9d635bacb15678d Mon Sep 17 00:00:00 2001
From: Erik tideman <erik.tideman@gmail.com>
Date: Thu, 5 Mar 2020 15:28:11 +0100
Subject: [PATCH 4/8] Changed HardwareTimer to use std::function instead of
 pointer as callbacks from interrupts

---
 cores/arduino/HardwareTimer.cpp | 41 ++++++---------------------------
 cores/arduino/HardwareTimer.h   | 17 +++++++-------
 cores/arduino/Tone.cpp          |  5 ++--
 3 files changed, 17 insertions(+), 46 deletions(-)

diff --git a/cores/arduino/HardwareTimer.cpp b/cores/arduino/HardwareTimer.cpp
index 8c9aed52b7..33ddd91c13 100644
--- a/cores/arduino/HardwareTimer.cpp
+++ b/cores/arduino/HardwareTimer.cpp
@@ -801,7 +801,7 @@ uint32_t HardwareTimer::getCaptureCompare(uint32_t channel,  TimerCompareFormat_
   *           HERTZ_FORMAT:    return value is the frequency in hertz for Capture/Compare value
   * @retval None
   */
-void HardwareTimer::setPWM(uint32_t channel, uint32_t pin, uint32_t frequency, uint32_t dutycycle, void (*PeriodCallback)(HardwareTimer *), void (*CompareCallback)(HardwareTimer *))
+void HardwareTimer::setPWM(uint32_t channel, uint32_t pin, uint32_t frequency, uint32_t dutycycle, callback_function_t PeriodCallback, callback_function_t CompareCallback)
 {
   setPWM(channel, digitalPinToPinName(pin), frequency, dutycycle, PeriodCallback, CompareCallback);
 }
@@ -818,7 +818,7 @@ void HardwareTimer::setPWM(uint32_t channel, uint32_t pin, uint32_t frequency, u
   *           HERTZ_FORMAT:    return value is the frequency in hertz for Capture/Compare value
   * @retval None
   */
-void HardwareTimer::setPWM(uint32_t channel, PinName pin, uint32_t frequency, uint32_t dutycycle, void (*PeriodCallback)(HardwareTimer *), void (*CompareCallback)(HardwareTimer *))
+void HardwareTimer::setPWM(uint32_t channel, PinName pin, uint32_t frequency, uint32_t dutycycle, callback_function_t PeriodCallback, callback_function_t CompareCallback)
 {
   setMode(channel, TIMER_OUTPUT_COMPARE_PWM1, pin);
   setOverflow(frequency, HERTZ_FORMAT);
@@ -848,13 +848,11 @@ void HardwareTimer::setInterruptPriority(uint32_t preemptPriority, uint32_t subP
 /**
   * @brief  Attach interrupt callback on update (rollover) event
   * @param  callback: interrupt callback
-  * @param  arg: pointer to optional argument to associate with interrupt
   * @retval None
   */
-void HardwareTimer::attachInterrupt(void (*callback)(HardwareTimer *), void *arg)
+void HardwareTimer::attachInterrupt(callback_function_t callback)
 {
-  args[0] = arg;
-  if (callbacks[0] != NULL) {
+  if (callbacks[0] != nullptr) {
     // Callback previously configured : do not clear neither enable IT, it is just a change of callback
     callbacks[0] = callback;
   } else {
@@ -877,7 +875,6 @@ 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;
 }
 
 /**
@@ -887,7 +884,7 @@ void HardwareTimer::detachInterrupt()
   * @param  arg: pointer to optional argument to associate with interrupt
   * @retval None
   */
-void HardwareTimer::attachInterrupt(uint32_t channel, void (*callback)(HardwareTimer *), void *arg)
+void HardwareTimer::attachInterrupt(uint32_t channel, callback_function_t callback)
 {
   int interrupt = getIT(channel);
   if (interrupt == -1) {
@@ -897,7 +894,6 @@ 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;
@@ -931,29 +927,6 @@ 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];
 }
 
 /**
@@ -1016,7 +989,7 @@ void HardwareTimer::updateCallback(TIM_HandleTypeDef *htim)
   HardwareTimer *HT = (HardwareTimer *)(obj->__this);
 
   if (HT->callbacks[0] != NULL) {
-    HT->callbacks[0](HT);
+    HT->callbacks[0]();
   }
 }
 
@@ -1057,7 +1030,7 @@ void HardwareTimer::captureCompareCallback(TIM_HandleTypeDef *htim)
   HardwareTimer *HT = (HardwareTimer *)(obj->__this);
 
   if (HT->callbacks[channel] != NULL) {
-    HT->callbacks[channel](HT);
+    HT->callbacks[channel]();
   }
 }
 
diff --git a/cores/arduino/HardwareTimer.h b/cores/arduino/HardwareTimer.h
index d8a33157ad..ca16a6a36e 100644
--- a/cores/arduino/HardwareTimer.h
+++ b/cores/arduino/HardwareTimer.h
@@ -92,6 +92,9 @@ typedef enum {
 
 #ifdef __cplusplus
 
+#include <functional>
+typedef std::function<void(void)> callback_function_t;
+
 /* Class --------------------------------------------------------*/
 class HardwareTimer {
   public:
@@ -109,8 +112,8 @@ class HardwareTimer {
     void setOverflow(uint32_t val, TimerFormat_t format = TICK_FORMAT); // set AutoReload register depending on format provided
     uint32_t getOverflow(TimerFormat_t format = TICK_FORMAT); // return overflow depending on format provided
 
-    void setPWM(uint32_t channel, PinName pin, uint32_t frequency, uint32_t dutycycle, void (*PeriodCallback)(HardwareTimer *) = NULL, void (*CompareCallback)(HardwareTimer *) = NULL); // Set all in one command freq in HZ, Duty in percentage. Including both interrup.
-    void setPWM(uint32_t channel, uint32_t pin, uint32_t frequency, uint32_t dutycycle, void (*PeriodCallback)(HardwareTimer *) = NULL, void (*CompareCallback)(HardwareTimer *) = NULL);
+    void setPWM(uint32_t channel, PinName pin, uint32_t frequency, uint32_t dutycycle, callback_function_t PeriodCallback = nullptr, callback_function_t CompareCallback = nullptr); // Set all in one command freq in HZ, Duty in percentage. Including both interrup.
+    void setPWM(uint32_t channel, uint32_t pin, uint32_t frequency, uint32_t dutycycle, callback_function_t PeriodCallback = nullptr, callback_function_t CompareCallback = nullptr);
 
 
     void setCount(uint32_t val, TimerFormat_t format = TICK_FORMAT); // set timer counter to value 'val' depending on format provided
@@ -126,16 +129,13 @@ class HardwareTimer {
     void setInterruptPriority(uint32_t preemptPriority, uint32_t subPriority); // set interrupt priority
 
     //Add interrupt to period update
-    void attachInterrupt(void (*handler)(HardwareTimer *), void *arg = NULL); // Attach interrupt callback which will be called upon update event (timer rollover)
+    void attachInterrupt(callback_function_t callback); // 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 *), void *arg = NULL); // Attach interrupt callback which will be called upon compare match event of specified channel
+    void attachInterrupt(uint32_t channel, callback_function_t callback); // 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
 
     // Refresh() is usefull while timer is running after some registers update
@@ -153,8 +153,7 @@ class HardwareTimer {
   private:
     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];
+    callback_function_t callbacks[1 + TIMER_CHANNELS]; //Callbacks: 0 for update, 1-4 for channels. (channel5/channel6, if any, doesn't have interrupt)
 
     int getChannel(uint32_t channel);
     int getLLChannel(uint32_t channel);
diff --git a/cores/arduino/Tone.cpp b/cores/arduino/Tone.cpp
index cb16254d75..c119906c1a 100644
--- a/cores/arduino/Tone.cpp
+++ b/cores/arduino/Tone.cpp
@@ -32,7 +32,7 @@ typedef struct {
 } timerPinInfo_t;
 
 static void timerTonePinInit(PinName p, uint32_t frequency, uint32_t duration);
-static void tonePeriodElapsedCallback(HardwareTimer *HT);
+static callback_function_t tonePeriodElapsedCallback();
 static timerPinInfo_t TimerTone_pinInfo = {NC, 0};
 static HardwareTimer *TimerTone = NULL;
 
@@ -41,9 +41,8 @@ static HardwareTimer *TimerTone = NULL;
   * @param  htim : timer handle
   * @retval None
   */
-static void tonePeriodElapsedCallback(HardwareTimer *HT)
+static callback_function_t tonePeriodElapsedCallback()
 {
-  UNUSED(HT);
   GPIO_TypeDef *port = get_GPIO_Port(STM_PORT(TimerTone_pinInfo.pin));
 
   if (port != NULL) {

From 029450f3e6a8a9feb7f51f4710a19b11e049cfc6 Mon Sep 17 00:00:00 2001
From: Erik tideman <erik.tideman@gmail.com>
Date: Thu, 5 Mar 2020 16:25:14 +0100
Subject: [PATCH 5/8] changed typedef -> using

---
 cores/arduino/HardwareTimer.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/cores/arduino/HardwareTimer.h b/cores/arduino/HardwareTimer.h
index 86e457ad2e..8b39af2816 100644
--- a/cores/arduino/HardwareTimer.h
+++ b/cores/arduino/HardwareTimer.h
@@ -93,7 +93,7 @@ typedef enum {
 #ifdef __cplusplus
 
 #include <functional>
-typedef std::function<void(void)> callback_function_t;
+using callback_function_t = std::function<void(void)>;
 
 /* Class --------------------------------------------------------*/
 class HardwareTimer {

From f9ea23c89f91cee73b9fca8492b617cead2d0066 Mon Sep 17 00:00:00 2001
From: Erik tideman <erik.tideman@gmail.com>
Date: Thu, 5 Mar 2020 17:07:11 +0100
Subject: [PATCH 6/8] Removed not relevent comment

---
 cores/arduino/HardwareTimer.cpp | 1 -
 cores/arduino/HardwareTimer.h   | 1 -
 2 files changed, 2 deletions(-)

diff --git a/cores/arduino/HardwareTimer.cpp b/cores/arduino/HardwareTimer.cpp
index 8cec82031a..9f343ba6da 100644
--- a/cores/arduino/HardwareTimer.cpp
+++ b/cores/arduino/HardwareTimer.cpp
@@ -939,7 +939,6 @@ void HardwareTimer::detachInterrupt()
   * @brief  Attach interrupt callback on Capture/Compare event
   * @param  channel: Arduino channel [1..4]
   * @param  callback: interrupt callback
-  * @param  arg: pointer to optional argument to associate with interrupt
   * @retval None
   */
 void HardwareTimer::attachInterrupt(uint32_t channel, callback_function_t callback)
diff --git a/cores/arduino/HardwareTimer.h b/cores/arduino/HardwareTimer.h
index 8b39af2816..1a3ee871f8 100644
--- a/cores/arduino/HardwareTimer.h
+++ b/cores/arduino/HardwareTimer.h
@@ -150,7 +150,6 @@ class HardwareTimer {
 
     // The following function(s) are available for more advanced timer options
     TIM_HandleTypeDef *getHandle();  // return the handle address for HAL related configuration
-
     int getChannel(uint32_t channel);
     int getLLChannel(uint32_t channel);
     int getIT(uint32_t channel);

From 5740040cb3de8e9a96a7d8bfebe80e823a67ab42 Mon Sep 17 00:00:00 2001
From: Erik tideman <erik.tideman@gmail.com>
Date: Fri, 6 Mar 2020 18:24:09 +0100
Subject: [PATCH 7/8] Updated missed HardwareTimer interface changes in
 Servo.cpp/SoftwareSerial.cpp/Tone.cpp

---
 cores/arduino/Tone.cpp                          | 4 ++--
 libraries/Servo/src/stm32/Servo.cpp             | 3 +--
 libraries/SoftwareSerial/src/SoftwareSerial.cpp | 3 +--
 libraries/SoftwareSerial/src/SoftwareSerial.h   | 2 +-
 4 files changed, 5 insertions(+), 7 deletions(-)

diff --git a/cores/arduino/Tone.cpp b/cores/arduino/Tone.cpp
index c119906c1a..7c475e50f9 100644
--- a/cores/arduino/Tone.cpp
+++ b/cores/arduino/Tone.cpp
@@ -32,7 +32,7 @@ typedef struct {
 } timerPinInfo_t;
 
 static void timerTonePinInit(PinName p, uint32_t frequency, uint32_t duration);
-static callback_function_t tonePeriodElapsedCallback();
+static void tonePeriodElapsedCallback();
 static timerPinInfo_t TimerTone_pinInfo = {NC, 0};
 static HardwareTimer *TimerTone = NULL;
 
@@ -41,7 +41,7 @@ static HardwareTimer *TimerTone = NULL;
   * @param  htim : timer handle
   * @retval None
   */
-static callback_function_t tonePeriodElapsedCallback()
+static void tonePeriodElapsedCallback()
 {
   GPIO_TypeDef *port = get_GPIO_Port(STM_PORT(TimerTone_pinInfo.pin));
 
diff --git a/libraries/Servo/src/stm32/Servo.cpp b/libraries/Servo/src/stm32/Servo.cpp
index 2202d2a6be..9bf4bb047d 100644
--- a/libraries/Servo/src/stm32/Servo.cpp
+++ b/libraries/Servo/src/stm32/Servo.cpp
@@ -40,9 +40,8 @@ uint8_t ServoCount = 0;                                    // the total number o
 /************ static functions common to all instances ***********************/
 
 volatile uint32_t CumulativeCountSinceRefresh = 0;
-static void Servo_PeriodElapsedCallback(HardwareTimer *HT)
+static void Servo_PeriodElapsedCallback()
 {
-  UNUSED(HT);
   // Only 1 timer used
   timer16_Sequence_t timer_id = _timer1;
 
diff --git a/libraries/SoftwareSerial/src/SoftwareSerial.cpp b/libraries/SoftwareSerial/src/SoftwareSerial.cpp
index 61fdbac6e1..da89fdd7c5 100644
--- a/libraries/SoftwareSerial/src/SoftwareSerial.cpp
+++ b/libraries/SoftwareSerial/src/SoftwareSerial.cpp
@@ -290,9 +290,8 @@ inline void SoftwareSerial::recv()
 //
 
 /* static */
-inline void SoftwareSerial::handleInterrupt(HardwareTimer *timer)
+inline void SoftwareSerial::handleInterrupt()
 {
-  UNUSED(timer);
   if (active_in) {
     active_in->recv();
   }
diff --git a/libraries/SoftwareSerial/src/SoftwareSerial.h b/libraries/SoftwareSerial/src/SoftwareSerial.h
index 6e9eb8fef4..c569fc2ec6 100644
--- a/libraries/SoftwareSerial/src/SoftwareSerial.h
+++ b/libraries/SoftwareSerial/src/SoftwareSerial.h
@@ -84,7 +84,7 @@ class SoftwareSerial : public Stream {
     void setRX();
     void setSpeed(uint32_t speed);
     void setRXTX(bool input);
-    static void handleInterrupt(HardwareTimer *timer);
+    static void handleInterrupt();
 
   public:
     // public methods

From 234994022d0a0983e3452125cdf1442f6f02570a Mon Sep 17 00:00:00 2001
From: Frederic Pillon <frederic.pillon@st.com>
Date: Tue, 10 Mar 2020 18:06:40 +0100
Subject: [PATCH 8/8] Update cores/arduino/HardwareTimer.cpp

---
 cores/arduino/HardwareTimer.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/cores/arduino/HardwareTimer.cpp b/cores/arduino/HardwareTimer.cpp
index 9f343ba6da..8568fdb896 100644
--- a/cores/arduino/HardwareTimer.cpp
+++ b/cores/arduino/HardwareTimer.cpp
@@ -910,7 +910,7 @@ void HardwareTimer::setInterruptPriority(uint32_t preemptPriority, uint32_t subP
   */
 void HardwareTimer::attachInterrupt(callback_function_t callback)
 {
-  if (callbacks[0] != nullptr) {
+  if (callbacks[0]) {
     // Callback previously configured : do not clear neither enable IT, it is just a change of callback
     callbacks[0] = callback;
   } else {