STM32/F7/L4: EXTI ALARM function no longer returns the xcpt_t oldhandler. There value is useless and dangerous after the recent changes to interrupt argument passing.

arch/arm/src/stm32/stm32_exti.h

@@ -102,15 +102,14 @@ xcpt_t stm32_gpiosetevent(uint32_t pinset, bool risingedge, bool fallingedge,
  *  - arg:    Argument passed to the interrupt callback
  *
  * Returns:
- *   The previous value of the interrupt handler function pointer.  This value may,
+ *   Zero (OK) on success; a negated errno value on failure indicating the
- *   for example, be used to restore the previous handler when multiple handlers are
+ *   nature of the failure.
- *   used.
  *
  ************************************************************************************/
 
 #ifdef CONFIG_RTC_ALARM
-xcpt_t stm32_exti_alarm(bool risingedge, bool fallingedge, bool event, xcpt_t func,
+int stm32_exti_alarm(bool risingedge, bool fallingedge, bool event, xcpt_t func,
-                        void *arg);
+                     void *arg);
 #endif
 
 #undef EXTERN

arch/arm/src/stm32/stm32_exti_alarm.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * arch/arm/src/stm32/stm32_exti_alarm.c
  *
- *   Copyright (C) 2009, 2012 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2009, 2012, 2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *           Diego Sanchez <dsanchez@nx-engineering.com>
  *
@@ -109,20 +109,16 @@ static int stm32_exti_alarm_isr(int irq, void *context, FAR void *arg)
  *  - arg:    Argument passed to the interrupt callback
  *
  * Returns:
- *   The previous value of the interrupt handler function pointer.  This
+ *   Zero (OK) on success; a negated errno value on failure indicating the
- *   value may, for example, be used to restore the previous handler when
+ *   nature of the failure.
- *   multiple handlers are used.
  *
  ****************************************************************************/
 
-xcpt_t stm32_exti_alarm(bool risingedge, bool fallingedge, bool event,
+int stm32_exti_alarm(bool risingedge, bool fallingedge, bool event,
-                        xcpt_t func, void *arg)
+                     xcpt_t func, void *arg)
 {
-  xcpt_t oldhandler;
-
   /* Get the previous GPIO IRQ handler; Save the new IRQ handler. */
 
-  oldhandler       = g_alarm_callback;
   g_alarm_callback = func;
   g_callback_arg   = arg;
 
@@ -158,5 +154,5 @@ xcpt_t stm32_exti_alarm(bool risingedge, bool fallingedge, bool event,
 
   /* Return the old IRQ handler */
 
-  return oldhandler;
+  return OK;
 }

arch/arm/src/stm32/stm32f40xxx_rtcc.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * arch/arm/src/stm32/stm32f40xxx_rtcc.c
  *
- *   Copyright (C) 2012-2016 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2012-2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *   Modified: Neil Hancock
  *
@@ -847,7 +847,7 @@ static inline void rtc_enable_alarm(void)
        * 3. Configure the RTC to generate RTC alarms (Alarm A or Alarm B).
        */
 
-      stm32_exti_alarm(true, false, true, stm32_rtc_alarm_handler, NULL);
+      (void)stm32_exti_alarm(true, false, true, stm32_rtc_alarm_handler, NULL);
       g_alarm_enabled = true;
     }
 }

arch/arm/src/stm32f7/stm32_exti.h

@@ -1,7 +1,7 @@
 /****************************************************************************
  * arch/arm/src/stm32f7/stm32_exti.h
  *
- *   Copyright (C) 2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2015, 2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -104,15 +104,14 @@ xcpt_t stm32_gpiosetevent(uint32_t pinset, bool risingedge, bool fallingedge,
  *  - arg:         Argument passed to the interrupt callback
  *
  * Returns:
- *   The previous value of the interrupt handler function pointer.  This
+ *   Zero (OK) on success; a negated errno value on failure indicating the
- *   value may, for example, be used to restore the previous handler when
+ *   nature of the failure.
- *   multiple handlers are used.
  *
  ****************************************************************************/
 
 #ifdef CONFIG_RTC_ALARM
-xcpt_t stm32_exti_alarm(bool risingedge, bool fallingedge, bool event,
+int stm32_exti_alarm(bool risingedge, bool fallingedge, bool event,
-                        xcpt_t func, void *arg);
+                     xcpt_t func, void *arg);
 #endif
 
 #undef EXTERN

arch/arm/src/stm32f7/stm32_exti_alarm.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * arch/arm/src/stm32f7/stm32_exti_alarm.c
  *
- *   Copyright (C) 2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2015, 2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * This file derives from similar logic for the STM32 F1:
@@ -57,10 +57,6 @@
 #include "stm32_gpio.h"
 #include "stm32_exti.h"
 
-/****************************************************************************
- * Pre-processor Definitions
- ****************************************************************************/
-
 /****************************************************************************
  * Private Data
  ****************************************************************************/
@@ -121,20 +117,16 @@ static int stm32_exti_alarm_isr(int irq, void *context, FAR void *arg)
  *  - arg:    Argument passed to the interrupt callback
  *
  * Returns:
- *   The previous value of the interrupt handler function pointer.  This
+ *   Zero (OK) on success; a negated errno value on failure indicating the
- *   value may, for example, be used to restore the previous handler when
+ *   nature of the failure.
- *   multiple handlers are used.
  *
  ****************************************************************************/
 
-xcpt_t stm32_exti_alarm(bool risingedge, bool fallingedge, bool event,
+int stm32_exti_alarm(bool risingedge, bool fallingedge, bool event,
-                        xcpt_t func, void *arg)
+                     xcpt_t func, void *arg)
 {
-  xcpt_t oldhandler;
-
   /* Get the previous GPIO IRQ handler; Save the new IRQ handler. */
 
-  oldhandler       = g_alarm_callback;
   g_alarm_callback = func;
   g_callback_arg   = arg;
 
@@ -170,5 +162,5 @@ xcpt_t stm32_exti_alarm(bool risingedge, bool fallingedge, bool event,
 
   /* Return the old IRQ handler */
 
-  return oldhandler;
+  return OK;
 }

arch/arm/src/stm32f7/stm32_rtc.c

@@ -1037,7 +1037,7 @@ int up_rtc_initialize(void)
    * 3. Configure the RTC to generate RTC alarms (Alarm A or Alarm B).
    */
 
-  stm32_exti_alarm(true, false, true, stm32_rtc_alarm_handler);
+  (void)stm32_exti_alarm(true, false, true, stm32_rtc_alarm_handler, NULL);
   rtc_dumpregs("After InitExtiAlarm");
 #else
   rtc_dumpregs("After Initialization");

arch/arm/src/stm32l4/stm32l4_exti.h

@@ -102,15 +102,14 @@ xcpt_t stm32l4_gpiosetevent(uint32_t pinset, bool risingedge, bool fallingedge,
  *  - arg:    Argument passed to the interrupt callback
  *
  * Returns:
- *   The previous value of the interrupt handler function pointer.  This
+ *   Zero (OK) on success; a negated errno value on failure indicating the
- *   value may, for example, be used to restore the previous handler when
+ *   nature of the failure.
- *   multiple handlers are used.
  *
  ****************************************************************************/
 
 #ifdef CONFIG_RTC_ALARM
-xcpt_t stm32l4_exti_alarm(bool risingedge, bool fallingedge, bool event,
+int stm32l4_exti_alarm(bool risingedge, bool fallingedge, bool event,
-                          xcpt_t func, void *arg);
+                       xcpt_t func, void *arg);
 #endif
 
 /****************************************************************************

arch/arm/src/stm32l4/stm32l4_exti_alarm.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * arch/arm/src/stm32l4/stm32l4_exti_alarm.c
  *
- *   Copyright (C) 2009, 2012 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2009, 2012, 2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *           Diego Sanchez <dsanchez@nx-engineering.com>
  *           dev@ziggurat29.com (adaptation to stm32l4)
@@ -109,20 +109,16 @@ static int stm32l4_exti_alarm_isr(int irq, void *context, FAR void *arg)
  *  - func:   when non-NULL, generate interrupt
  *
  * Returns:
- *   The previous value of the interrupt handler function pointer.  This
+ *   Zero (OK) on success; a negated errno value on failure indicating the
- *   value may, for example, be used to restore the previous handler when
+ *   nature of the failure.
- *   multiple handlers are used.
  *
  ****************************************************************************/
 
-xcpt_t stm32l4_exti_alarm(bool risingedge, bool fallingedge, bool event,
+int stm32l4_exti_alarm(bool risingedge, bool fallingedge, bool event,
-                          xcpt_t func, void *arg)
+                       xcpt_t func, void *arg)
 {
-  xcpt_t oldhandler;
-
   /* Get the previous GPIO IRQ handler; Save the new IRQ handler. */
 
-  oldhandler       = g_alarm_callback;
   g_alarm_callback = func;
   g_callback_arg   = arg;
 
@@ -158,5 +154,5 @@ xcpt_t stm32l4_exti_alarm(bool risingedge, bool fallingedge, bool event,
 
   /* Return the old IRQ handler */
 
-  return oldhandler;
+  return OK;
 }

arch/arm/src/stm32l4/stm32l4_rtcc.c

@@ -801,7 +801,7 @@ static inline void rtc_enable_alarm(void)
        * 3. Configure the RTC to generate RTC alarms (Alarm A or Alarm B).
        */
 
-      stm32l4_exti_alarm(true, false, true, stm32l4_rtc_alarm_handler, NULL);
+      (void)stm32l4_exti_alarm(true, false, true, stm32l4_rtc_alarm_handler, NULL);
       g_alarm_enabled = true;
     }
 }