board_button_irq: Button IRQ logic no longer returns the xcpt_t oldhandler. There value is useless and dangerous after the recent changes to interrupt argument passing.

arch/avr/src/at32uc3/at32uc3.h

@@ -296,7 +296,7 @@ void weak_function gpio_irqinitialize(void);
  ****************************************************************************/
 
 #ifdef CONFIG_AVR32_GPIOIRQ
-int gpio_irqattach(int irq, xcpt_t newisr, xcpt_t *oldisr);
+int gpio_irqattach(int irq, xcpt_t handler, void *arg);
 #endif
 
 /****************************************************************************

arch/avr/src/at32uc3/at32uc3_gpioirq.c

@@ -57,20 +57,22 @@
 #ifdef CONFIG_AVR32_GPIOIRQ
 
 /****************************************************************************
- * Pre-processor Definitions
+ * Private Types
  ****************************************************************************/
 
+struct g_gpiohandler_s
+{
+  xcpt_t handler;   /* Interrupt handler entry point */
+  void  *arg;       /* The argument that accompanies the interrupt handler */
+};
+
 /****************************************************************************
  * Private Data
  ****************************************************************************/
 
 /* A table of handlers for each GPIO interrupt */
 
-static FAR xcpt_t g_gpiohandler[NR_GPIO_IRQS];
-
-/****************************************************************************
- * Public Data
- ****************************************************************************/
+static struct g_gpiohandler_s g_gpiohandler[NR_GPIO_IRQS];
 
 /****************************************************************************
  * Private Functions
@@ -221,10 +223,10 @@ static void gpio_porthandler(uint32_t regbase, int irqbase, uint32_t irqset, voi
 
               /* Dispatch handling for this pin */
 
-              xcpt_t handler = g_gpiohandler[irq];
-              if (handler)
+              xcpt_t handler = g_gpiohandler[irq].handler;
+              if (handler != NULL)
                 {
-                  handler(irq, context);
+                  handler(irq, contex, g_gpiohandler[irq].arg);
                 }
               else
                 {
@@ -304,7 +306,8 @@ void gpio_irqinitialize(void)
 
   for (i = 0; i < NR_GPIO_IRQS; i++)
     {
-      g_gpiohandler[i] = irq_unexpected_isr;
+      g_gpiohandler[i].handler = irq_unexpected_isr;
+      g_gpiohandler[i].arg     = NULL;
     }
 
   /* Then attach the GPIO interrupt handlers */
@@ -325,7 +328,7 @@ void gpio_irqinitialize(void)
  *
  ****************************************************************************/
 
-int gpio_irqattach(int irq, xcpt_t newisr, xcpt_t *oldisr)
+int gpio_irqattach(int irq, xcpt_t handler, void *arg)
 {
   irqstate_t flags;
   int        ret = -EINVAL;
@@ -338,25 +341,23 @@ int gpio_irqattach(int irq, xcpt_t newisr, xcpt_t *oldisr)
        */
 
       flags = enter_critical_section();
-      if (newisr == NULL)
+      if (handler == NULL)
         {
            gpio_irqdisable(irq);
-           newisr = irq_unexpected_isr;
+
+           handler = irq_unexpected_isr;
+           arg     = NULL;
         }
 
-      /* Return the old ISR (in case the caller ever wants to restore it) */
+      /* Save the new ISR in the table. */
 
-      if (oldisr)
-        {
-          *oldisr = g_gpiohandler[irq];
-        }
+      g_gpiohandler[irq].handler = handler;
+      g_gpiohandler[irq].arg     = arg;
 
-      /* Then save the new ISR in the table. */
-
-      g_gpiohandler[irq] = newisr;
       leave_critical_section(flags);
       ret = OK;
     }
+
   return ret;
 }
 

configs/avr32dev1/src/avr32_buttons.c

@@ -42,6 +42,7 @@
 
 #include <sys/types.h>
 #include <stdint.h>
+#include <errno.h>
 
 #include <nuttx/arch.h>
 #include <nuttx/board.h>
@@ -69,28 +70,26 @@
 
 #if defined(CONFIG_AVR32_GPIOIRQ) && defined(CONFIG_ARCH_IRQBUTTONS) && \
    (defined(CONFIG_AVR32DEV_BUTTON1_IRQ) || defined(CONFIG_AVR32DEV_BUTTON2_IRQ))
-static xcpt_t board_button_irqx(int irq, xcpt_t irqhandler, void *arg)
+static int board_button_irqx(int irq, xcpt_t irqhandler, void *arg)
 {
-  xcpt_t oldhandler;
-
   /* Attach the handler */
 
-  gpio_irqattach(irq, irqhandler, &oldhandler);
-
-  /* Enable/disable the interrupt */
-
-  if (irqhandler)
+  int ret = gpio_irqattach(irq, irqhandler, &oldhandler, arg);
+  if (ret >= 0)
     {
-      gpio_irqenable(irq);
-    }
-  else
-    {
-      gpio_irqdisable(irq);
+      /* Enable/disable the interrupt */
+
+      if (irqhandler != NULL)
+        {
+          gpio_irqenable(irq);
+        }
+      else
+        {
+         gpio_irqdisable(irq);
+       }
     }
 
-  /* Return the old button handler (so that it can be restored) */
-
-  return oldhandler;
+  return OK;
 }
 #endif
 
@@ -143,8 +142,7 @@ uint8_t board_buttons(void)
  * Description:
  *   This function may be called to register an interrupt handler that will
  *   be called when a button is depressed or released.  The ID value is one
- *   of the BUTTON* definitions provided above. The previous interrupt
- *   handler address isreturned (so that it may restored, if so desired).
+ *   of the BUTTON* definitions provided above.
  *
  * Configuration Notes:
  *   Configuration CONFIG_AVR32_GPIOIRQ must be selected to enable the
@@ -156,25 +154,29 @@ uint8_t board_buttons(void)
  ****************************************************************************/
 
 #if defined(CONFIG_AVR32_GPIOIRQ) && defined(CONFIG_ARCH_IRQBUTTONS)
-xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
+int board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 {
+  int ret;
+
 #ifdef CONFIG_AVR32DEV_BUTTON1_IRQ
   if (id == BUTTON1)
     {
-      return board_button_irqx(GPIO_BUTTON1_IRQ, irqhandler, arg);
+      ret = board_button_irqx(GPIO_BUTTON1_IRQ, irqhandler, arg);
     }
   else
 #endif
 #ifdef CONFIG_AVR32DEV_BUTTON2_IRQ
   if (id == BUTTON2)
     {
-      return board_button_irqx(GPIO_BUTTON2_IRQ, irqhandler, arg);
+      ret = board_button_irqx(GPIO_BUTTON2_IRQ, irqhandler, arg);
     }
   else
 #endif
     {
-      return NULL;
+      ret = -EINVAL;
     }
+
+  return ret;
 }
 #endif
 #endif /* CONFIG_ARCH_BUTTONS */

configs/bambino-200e/src/lpc43_buttons.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * configs/bambino-200e/src/lpc43_buttons.c
  *
- *   Copyright (C) 2016 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2016-2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *           Alan Carvalho de Assis acassis@gmail.com [nuttx] <nuttx@yahoogroups.com>
  *
@@ -66,13 +66,7 @@ static const uint16_t g_buttoncfg[BOARD_NUM_BUTTONS] =
   BAMBINO_BUT1
 };
 
-/* This array defines all of the interrupt handlers current attached to
- * button events.
- */
-
 #if defined(CONFIG_ARCH_IRQBUTTONS) && defined(CONFIG_LPC43_GPIO_IRQ)
-static xcpt_t g_buttonisr[BOARD_NUM_BUTTONS];
-
 /* This array provides the mapping from button ID numbers to button IRQ
  * numbers.
  */
@@ -161,8 +155,7 @@ uint8_t board_buttons(void)
  *   be called when a button is depressed or released.  The ID value is a
  *   button enumeration value that uniquely identifies a button resource. See the
  *   BOARD_BUTTON_* and BOARD_JOYSTICK_* definitions in board.h for the meaning
- *   of enumeration values.  The previous interrupt handler address is returned
- *   (so that it may restored, if so desired).
+ *   of enumeration values.
  *
  *   Note that board_button_irq() also enables button interrupts.  Button
  *   interrupts will remain enabled after the interrupt handler is attached.
@@ -172,9 +165,8 @@ uint8_t board_buttons(void)
  ****************************************************************************/
 
 #if defined(CONFIG_ARCH_IRQBUTTONS) && defined(CONFIG_LPC43_GPIO_IRQ)
-xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
+int board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 {
-  xcpt_t oldhandler = NULL;
   irqstate_t flags;
   int irq;
 
@@ -182,11 +174,6 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 
   if ((unsigned)id < BOARD_NUM_BUTTONS)
     {
-      /* Return the current button handler and set the new interrupt handler */
-
-      oldhandler      = g_buttonisr[id];
-      g_buttonisr[id] = irqhandler;
-
       /* Disable interrupts until we are done */
 
       flags = enter_critical_section();
@@ -200,7 +187,7 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
         {
           /* Attach then enable the new interrupt handler */
 
-          (void)irq_attach(irq, irqhandler, NULL);
+          (void)irq_attach(irq, irqhandler, arg);
           up_enable_irq(irq);
         }
       else
@@ -210,10 +197,11 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
           up_disable_irq(irq);
           (void)irq_detach(irq);
         }
+
       leave_critical_section(flags);
     }
 
-  return oldhandler;
+  return OK;
 }
 #endif
 

configs/cloudctrl/src/stm32_buttons.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * configs/cloudctrl/src/stm32_buttons.c
  *
- *   Copyright (C) 2012, 2014-2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2012, 2014-2015, 2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *           Darcy Gong <darcy.gong@gmail.com>
  *
@@ -151,15 +151,13 @@ uint8_t board_buttons(void)
  *   board_button_irq() may be called to register an interrupt handler that will
  *   be called when a button is depressed or released.  The ID value is a
  *   button enumeration value that uniquely identifies a button resource. See
- *   the
- *   BUTTON_* and JOYSTICK_* definitions in board.h for the meaning of
- *   enumeration  value.  The previous interrupt handler address is returned
- *   (so that it may restored, if so desired).
+ *   the BUTTON_* and JOYSTICK_* definitions in board.h for the meaning of
+ *   enumeration  value.
  *
  ****************************************************************************/
 
 #ifdef CONFIG_ARCH_IRQBUTTONS
-xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
+int board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 {
   xcpt_t oldhandler = NULL;
 
@@ -171,7 +169,8 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
                                       irqhandler, arg);
     }
 
-  return oldhandler;
+  UNUSED(oldhandler);
+  return OK;
 }
 #endif
 #endif /* CONFIG_ARCH_BUTTONS */

configs/dk-tm4c129x/src/tm4c_buttons.c

@@ -40,6 +40,7 @@
 #include <nuttx/config.h>
 
 #include <stdint.h>
+#include <errno.h>
 
 #include <nuttx/arch.h>
 #include <nuttx/board.h>
@@ -144,18 +145,16 @@ uint8_t board_buttons(void)
  *   be called when a button is depressed or released.  The ID value is a
  *   button enumeration value that uniquely identifies a button resource. See the
  *   BUTTON_* and JOYSTICK_* definitions in board.h for the meaning of enumeration
- *   value.  The previous interrupt handler address is returned (so that it may
- *   restored, if so desired).
+ *   value.
  *
  ************************************************************************************/
 
 #if defined(CONFIG_ARCH_IRQBUTTONS) && defined(CONFIG_TIVA_GPIOP_IRQS)
-xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
+int board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 {
   static xcpt_t handler = NULL;
-  xcpt_t oldhandler = handler;
   irqstate_t flags;
-  int ret;
+  int ret = -EINVAL;
 
   /* Interrupts are supported only on ports P and Q and, hence, only on button SW4 */
 
@@ -186,7 +185,7 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
       leave_critical_section(flags);
     }
 
-  return oldhandler;
+  return ret;
 }
 #endif
 #endif /* CONFIG_ARCH_BUTTONS */

configs/fire-stm32v2/src/stm32_buttons.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * configs/fire-stm32v2/src/stm32_buttons.c
  *
- *   Copyright (C) 2012, 2014-2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2012, 2014-2015, 2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -128,14 +128,14 @@ uint8_t board_buttons(void)
  *   be called when a button is depressed or released.  The ID value is a
  *   button enumeration value that uniquely identifies a button resource. See
  *   the BUTTON_* and JOYSTICK_* definitions in board.h for the meaning of
- *   enumeration values.  The previous interrupt handler address is returned
- *   (so that it may restored, if so desired).
+ *   enumeration values.
  *
  ****************************************************************************/
 
 #ifdef CONFIG_ARCH_IRQBUTTONS
-xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
+int board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 {
+  xcpt_t oldhandler;
   uint16_t gpio;
 
   if (id == BUTTON_KEY1)
@@ -151,7 +151,10 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
       return NULL;
     }
 
-  return stm32_gpiosetevent(gpio, true, true, true, irqhandler, arg);
+  oldhandler = stm32_gpiosetevent(gpio, true, true, true, irqhandler, arg);
+
+  UNUSED(oldhandler);
+  return OK;
 }
 #endif
 #endif /* CONFIG_ARCH_BUTTONS */

configs/freedom-k64f/src/k64_buttons.c

@@ -40,6 +40,7 @@
 #include <nuttx/config.h>
 
 #include <stdint.h>
+#include <errno.h>
 
 #include <nuttx/arch.h>
 #include <nuttx/board.h>
@@ -127,16 +128,15 @@ uint8_t board_buttons(void)
  *   will be called when a button is depressed or released.  The ID value is
  *   a button enumeration value that uniquely identifies a button resource.
  *   See the BUTTON_* and JOYSTICK_* definitions in board.h for the meaning
- *   of enumeration value.  The previous interrupt handler address is
- *   returned (so that it may restored, if so desired).
+ *   of enumeration value.
  *
  ****************************************************************************/
 
 #ifdef CONFIG_ARCH_IRQBUTTONS
-xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
+int board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 {
-  xcpt_t oldhandler;
   uint32_t pinset;
+  int ret;
 
   /* Map the button id to the GPIO bit set. */
 
@@ -150,7 +150,7 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
     }
   else
     {
-      return NULL;
+      return -EINVAL;
     }
 
   /* The button has already been configured as an interrupting input (by
@@ -159,12 +159,15 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
    * Attach the new button handler.
    */
 
-  oldhandler = knetis_pinirqattach(pinset, irqhandler);
+  ret = kinetis_pinirqattach(pinset, irqhandler);
+  if (ret >= 0)
+    {
+      /* Then make sure that interrupts are enabled on the pin */
 
-  /* Then make sure that interrupts are enabled on the pin */
+      kinetis_pindmaenable(pinset);
+    }
 
-  kinetis_pindmaenable(pinset);
-  return oldhandler;
+  return ret;
 }
 #endif
 #endif /* CONFIG_ARCH_BUTTONS */

configs/freedom-k66f/src/k66_buttons.c

@@ -41,6 +41,7 @@
 #include <nuttx/config.h>
 
 #include <stdint.h>
+#include <errno.h>
 
 #include <nuttx/arch.h>
 #include <nuttx/board.h>
@@ -131,13 +132,12 @@ uint8_t board_buttons(void)
  *   will be called when a button is depressed or released.  The ID value is
  *   a button enumeration value that uniquely identifies a button resource.
  *   See the BUTTON_* and JOYSTICK_* definitions in board.h for the meaning
- *   of enumeration value.  The previous interrupt handler address is
- *   returned (so that it may restored, if so desired).
+ *   of enumeration value.
  *
  ****************************************************************************/
 
 #ifdef CONFIG_ARCH_IRQBUTTONS
-xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
+int board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 {
   uint32_t pinset;
 
@@ -153,7 +153,7 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
     }
   else
     {
-      return NULL;
+      return -EINVAL;
     }
 
   /* The button has already been configured as an interrupting input (by
@@ -162,11 +162,14 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
    * Attach the new button handler.
    */
 
-  (void)kinetis_pinirqattach(pinset, irqhandler, NULL);
+  ret = kinetis_pinirqattach(pinset, irqhandler, NULL);
+  if (ret >= 0)
+    {
+      /* Then make sure that interrupts are enabled on the pin */
 
-  /* Then make sure that interrupts are enabled on the pin */
+      kinetis_pinirqenable(pinset);
+    }
 
-  kinetis_pinirqenable(pinset);
   return NULL;
 }
 #endif

configs/hymini-stm32v/src/stm32_buttons.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * configs/hymini-stm32v/src/stm32_buttons.c
  *
- *   Copyright (C) 2009, 2011, 2014-2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2009, 2011, 2014-2015, 2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -69,39 +69,44 @@
  ****************************************************************************/
 
 void board_button_initialize(void)
-  {
-    stm32_configgpio(GPIO_BTN_KEYA);
-    stm32_configgpio(GPIO_BTN_KEYB);
-  }
+{
+  stm32_configgpio(GPIO_BTN_KEYA);
+  stm32_configgpio(GPIO_BTN_KEYB);
+}
 
 /****************************************************************************
  * Name: board_buttons
  ****************************************************************************/
 
 uint8_t board_buttons(void)
-  {
-    uint8_t ret = 0;
-    bool pinValue;
+{
+  uint8_t ret = 0;
+  bool pinValue;
 
-    /* Check that state of each key */
+  /* Check that state of each key */
 
-    /* Pin is pulled up */
-    pinValue = stm32_gpioread(GPIO_BTN_KEYA);
-    if (!pinValue)
-      {
-        // Button pressed
-        ret = 1 << BUTTON_KEYA;
-      }
+  /* Pin is pulled up */
 
-    /* Pin is pulled down */
-    pinValue = stm32_gpioread(GPIO_BTN_KEYB);
-    if (pinValue)
-      {
-        // Button pressed
-        ret |= 1 << BUTTON_KEYB;
-      }
-    return ret;
-  }
+  pinValue = stm32_gpioread(GPIO_BTN_KEYA);
+  if (!pinValue)
+    {
+      /* Button pressed */
+
+      ret = 1 << BUTTON_KEYA;
+    }
+
+  /* Pin is pulled down */
+
+  pinValue = stm32_gpioread(GPIO_BTN_KEYB);
+  if (pinValue)
+    {
+      /* Button pressed */
+
+      ret |= 1 << BUTTON_KEYB;
+    }
+
+  return ret;
+}
 
 /****************************************************************************
  * Button support.
@@ -122,28 +127,29 @@ uint8_t board_buttons(void)
  *   be called when a button is depressed or released.  The ID value is a
  *   button enumeration value that uniquely identifies a button resource. See
  *   the BUTTON_* definitions in board.h for the meaning of enumeration
- *   value.  The previous interrupt handler address is returned (so that it
- *    may be restored, if so desired).
+ *   value.
  *
  ****************************************************************************/
 
 #ifdef CONFIG_ARCH_IRQBUTTONS
-xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
-  {
-    xcpt_t oldhandler = NULL;
-    uint32_t pinset = GPIO_BTN_KEYA;
+int board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
+{
+  xcpt_t oldhandler = NULL;
+  uint32_t pinset = GPIO_BTN_KEYA;
 
-    if (id == 1)
-      {
-        pinset = GPIO_BTN_KEYB;
-      }
-    if (id < 2)
-      {
-        oldhandler = stm32_gpiosetevent(pinset, true, true, true,
-                                        irqhandler, arg);
-      }
+  if (id == 1)
+    {
+      pinset = GPIO_BTN_KEYB;
+    }
 
-    return oldhandler;
-  }
+  if (id < 2)
+    {
+      oldhandler = stm32_gpiosetevent(pinset, true, true, true,
+                                      irqhandler, arg);
+    }
+
+  UNUSED(oldhandler);
+  return OK;
+}
 #endif
 #endif /* CONFIG_ARCH_BUTTONS */

configs/kwikstik-k40/src/k40_buttons.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * configs/kwikstik-k40/src/k40_buttons.c
  *
- *   Copyright (C) 2011, 2014-2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2011, 2014-2015, 2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -40,6 +40,7 @@
 #include <nuttx/config.h>
 
 #include <stdint.h>
+#include <errno.h>
 
 #include <nuttx/arch.h>
 #include <nuttx/board.h>
@@ -49,18 +50,6 @@
 
 #ifdef CONFIG_ARCH_BUTTONS
 
-/****************************************************************************
- * Pre-processor Definitions
- ****************************************************************************/
-
-/****************************************************************************
- * Private Data
- ****************************************************************************/
-
-/****************************************************************************
- * Private Functions
- ****************************************************************************/
-
 /****************************************************************************
  * Public Functions
  ****************************************************************************/
@@ -111,17 +100,16 @@ uint8_t board_buttons(void)
  *   be called when a button is depressed or released.  The ID value is a
  *   button enumeration value that uniquely identifies a button resource.
  *   See the BUTTON_* and JOYSTICK_* definitions in board.h for the meaning
- *   of enumeration value.  The previous interrupt handler address is
- *   returned (so that it may be restored, if so desired).
+ *   of enumeration value.
  *
  ****************************************************************************/
 
 #ifdef CONFIG_ARCH_IRQBUTTONS
-xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
+int board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 {
   /* The KwikStik-K40 board has no standard GPIO contact buttons */
 
-  return NULL;
+  return -EINVAL;
 }
 #endif
 #endif /* CONFIG_ARCH_BUTTONS */

configs/launchxl-tms57004/src/tms570_buttons.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * configs/sam4e-ek/src/tms570_buttons.c
  *
- *   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
@@ -40,6 +40,7 @@
 #include <nuttx/config.h>
 
 #include <stdint.h>
+#include <errno.h>
 
 #include <nuttx/arch.h>
 #include <nuttx/board.h>
@@ -84,10 +85,9 @@ static xcpt_t g_irq_button;
  ****************************************************************************/
 
 #ifdef HAVE_IRQBUTTONS
-static xcpt_t board_button_irqx(gio_pinset_t pinset, int irq,
-                                xcpt_t irqhandler, xcpt_t *store, void *arg)
+static int board_button_irqx(gio_pinset_t pinset, int irq,
+                             xcpt_t irqhandler, xcpt_t *store, void *arg)
 {
-  xcpt_t oldhandler;
   irqstate_t flags;
 
   /* Disable interrupts until we are done.  This guarantees that the following
@@ -98,7 +98,6 @@ static xcpt_t board_button_irqx(gio_pinset_t pinset, int irq,
 
   /* Get the old button interrupt handler and save the new one */
 
-  oldhandler = *store;
   *store = irqhandler;
 
   /* Are we attaching or detaching? */
@@ -123,7 +122,7 @@ static xcpt_t board_button_irqx(gio_pinset_t pinset, int irq,
 
   /* Return the old button handler (so that it can be restored) */
 
-  return oldhandler;
+  return OK;
 }
 #endif
 
@@ -171,8 +170,7 @@ uint8_t board_buttons(void)
  * Description:
  *   This function may be called to register an interrupt handler that will
  *   be called when a button is depressed or released.  The ID value is one
- *   of the BUTTON* definitions provided above. The previous interrupt
- *   handler address is returned (so that it may restored, if so desired).
+ *   of the BUTTON* definitions provided above.
  *
  * Configuration Notes:
  *   Configuration CONFIG_AVR32_GIOIRQ must be selected to enable the
@@ -183,7 +181,7 @@ uint8_t board_buttons(void)
  *
  ****************************************************************************/
 
-xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
+int board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 {
 #ifdef HAVE_IRQBUTTONS
   if (id == BUTTON_GIOA7)
@@ -193,8 +191,7 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
     }
 #endif
 
-  return NULL;
-
+  return -EINVAL;
 }
 
 #endif /* CONFIG_ARCH_BUTTONS */

configs/lincoln60/src/lpc17_buttons.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * configs/lincoln60/src/lpc17_buttons.c
  *
- *   Copyright (C) 2012-2013, 2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2012-2013, 2015, 2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -69,13 +69,7 @@ static const uint16_t g_buttoncfg[BOARD_NUM_BUTTONS] =
   LINCOLN60_BUT1
 };
 
-/* This array defines all of the interrupt handlers current attached to
- * button events.
- */
-
 #if defined(CONFIG_ARCH_IRQBUTTONS) && defined(CONFIG_LPC17_GPIOIRQ)
-static xcpt_t g_buttonisr[BOARD_NUM_BUTTONS];
-
 /* This array provides the mapping from button ID numbers to button IRQ
  * numbers.
  */
@@ -168,8 +162,7 @@ uint8_t board_buttons(void)
  *   be called when a button is depressed or released.  The ID value is a
  *   button enumeration value that uniquely identifies a button resource. See the
  *   BOARD_BUTTON_* and BOARD_JOYSTICK_* definitions in board.h for the meaning
- *   of enumeration values.  The previous interrupt handler address is returned
- *   (so that it may restored, if so desired).
+ *   of enumeration values.
  *
  *   Note that board_button_irq() also enables button interrupts.  Button
  *   interrupts will remain enabled after the interrupt handler is attached.
@@ -179,9 +172,8 @@ uint8_t board_buttons(void)
  ****************************************************************************/
 
 #if defined(CONFIG_ARCH_IRQBUTTONS) && defined(CONFIG_LPC17_GPIOIRQ)
-xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
+int board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 {
-  xcpt_t oldhandler = NULL;
   irqstate_t flags;
   int irq;
 
@@ -189,11 +181,6 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 
   if ((unsigned)id < BOARD_NUM_BUTTONS)
     {
-      /* Return the current button handler and set the new interrupt handler */
-
-      oldhandler      = g_buttonisr[id];
-      g_buttonisr[id] = irqhandler;
-
       /* Disable interrupts until we are done */
 
       flags = enter_critical_section();
@@ -207,7 +194,7 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
         {
           /* Attach then enable the new interrupt handler */
 
-          (void)irq_attach(irq, irqhandler, NULL);
+          (void)irq_attach(irq, irqhandler, arg);
           up_enable_irq(irq);
         }
       else
@@ -217,9 +204,11 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
           up_disable_irq(irq);
           (void)irq_detach(irq);
         }
+
       leave_critical_section(flags);
     }
-  return oldhandler;
+
+  return OK;
 }
 #endif
 

configs/lpc4330-xplorer/src/lpc43_buttons.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * configs/lpc4330-xplorer/src/lpc43_buttons.c
  *
- *   Copyright (C) 2012, 2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2012, 2015, 2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -68,13 +68,7 @@ static const uint16_t g_buttoncfg[BOARD_NUM_BUTTONS] =
   LPC4330_XPLORER_BUT1
 };
 
-/* This array defines all of the interrupt handlers current attached to
- * button events.
- */
-
 #if defined(CONFIG_ARCH_IRQBUTTONS) && defined(CONFIG_LPC43_GPIO_IRQ)
-static xcpt_t g_buttonisr[BOARD_NUM_BUTTONS];
-
 /* This array provides the mapping from button ID numbers to button IRQ
  * numbers.
  */
@@ -167,8 +161,7 @@ uint8_t board_buttons(void)
  *   be called when a button is depressed or released.  The ID value is a
  *   button enumeration value that uniquely identifies a button resource. See the
  *   BOARD_BUTTON_* and BOARD_JOYSTICK_* definitions in board.h for the meaning
- *   of enumeration values.  The previous interrupt handler address is returned
- *   (so that it may restored, if so desired).
+ *   of enumeration values.
  *
  *   Note that board_button_irq() also enables button interrupts.  Button
  *   interrupts will remain enabled after the interrupt handler is attached.
@@ -178,9 +171,8 @@ uint8_t board_buttons(void)
  ****************************************************************************/
 
 #if defined(CONFIG_ARCH_IRQBUTTONS) && defined(CONFIG_LPC43_GPIO_IRQ)
-xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
+int board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 {
-  xcpt_t oldhandler = NULL;
   irqstate_t flags;
   int irq;
 
@@ -188,11 +180,6 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 
   if ((unsigned)id < BOARD_NUM_BUTTONS)
     {
-      /* Return the current button handler and set the new interrupt handler */
-
-      oldhandler      = g_buttonisr[id];
-      g_buttonisr[id] = irqhandler;
-
       /* Disable interrupts until we are done */
 
       flags = enter_critical_section();
@@ -206,7 +193,7 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
         {
           /* Attach then enable the new interrupt handler */
 
-          (void)irq_attach(irq, irqhandler, NULL);
+          (void)irq_attach(irq, irqhandler, arg);
           up_enable_irq(irq);
         }
       else
@@ -216,9 +203,11 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
           up_disable_irq(irq);
           (void)irq_detach(irq);
         }
+
       leave_critical_section(flags);
     }
-  return oldhandler;
+
+  return OK;
 }
 #endif
 

configs/lpc4357-evb/src/lpc43_buttons.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * configs/lpc4357-evb/src/board_buttons.c
  *
- *   Copyright (C) 2014-2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2014-2015, 2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -41,6 +41,7 @@
 
 #include <stdint.h>
 #include <stdbool.h>
+#include <errno.h>
 
 #include <nuttx/arch.h>
 #include <nuttx/board.h>
@@ -68,13 +69,7 @@ static const uint16_t g_buttoncfg[BOARD_NUM_BUTTONS] =
 {
 };
 
-/* This array defines all of the interrupt handlers current attached to
- * button events.
- */
-
 #if defined(CONFIG_ARCH_IRQBUTTONS) && defined(CONFIG_LPC43_GPIO_IRQ)
-static xcpt_t g_buttonisr[BOARD_NUM_BUTTONS];
-
 /* This array provides the mapping from button ID numbers to button IRQ
  * numbers.
  */
@@ -173,8 +168,7 @@ uint8_t board_buttons(void)
  *   be called when a button is depressed or released.  The ID value is a
  *   button enumeration value that uniquely identifies a button resource. See the
  *   BOARD_BUTTON_* and BOARD_JOYSTICK_* definitions in board.h for the meaning
- *   of enumeration values.  The previous interrupt handler address is returned
- *   (so that it may restored, if so desired).
+ *   of enumeration values.
  *
  *   Note that board_button_irq() also enables button interrupts.  Button
  *   interrupts will remain enabled after the interrupt handler is attached.
@@ -187,7 +181,6 @@ uint8_t board_buttons(void)
 xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 {
 #if 0 /* Not yet implemented */
-  xcpt_t oldhandler = NULL;
   irqstate_t flags;
   int irq;
 
@@ -195,11 +188,6 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 
   if ((unsigned)id < BOARD_NUM_BUTTONS)
     {
-      /* Return the current button handler and set the new interrupt handler */
-
-      oldhandler      = g_buttonisr[id];
-      g_buttonisr[id] = irqhandler;
-
       /* Disable interrupts until we are done */
 
       flags = enter_critical_section();
@@ -213,7 +201,7 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
         {
           /* Attach then enable the new interrupt handler */
 
-          (void)irq_attach(irq, irqhandler, NULL);
+          (void)irq_attach(irq, irqhandler, arg);
           up_enable_irq(irq);
         }
       else
@@ -223,12 +211,13 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
           up_disable_irq(irq);
           (void)irq_detach(irq);
         }
+
       leave_critical_section(flags);
     }
 
-  return oldhandler;
+  return OK;
 #else
-  return NULL;
+  return -ENOSYS;
 #endif /* Not yet implemented */
 }
 #endif

configs/nucleo-144/src/stm32_buttons.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * configs/nucleo-144/src/stm32_buttons.c
  *
- *   Copyright (C) 2016 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2016-2017 Gregory Nutt. All rights reserved.
  *   Authors: Gregory Nutt <gnutt@nuttx.org>
  *            David Sidrane <david_s5@nscdg.com>
  *
@@ -99,13 +99,12 @@ uint8_t board_buttons(void)
  *   be called when a button is depressed or released.  The ID value is a
  *   button enumeration value that uniquely identifies a button resource. See the
  *   BUTTON_* definitions in board.h for the meaning of enumeration
- *   value.  The previous interrupt handler address is returned (so that it may
- *   restored, if so desired).
+ *   value.
  *
  ************************************************************************************/
 
 #ifdef CONFIG_ARCH_IRQBUTTONS
-xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
+int board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 {
   xcpt_t oldhandler = NULL;
 
@@ -115,7 +114,8 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
                                       irqhandler, arg);
     }
 
-  return oldhandler;
+  UNUSED(oldhandler);
+  return OK;
 }
 #endif
 #endif /* CONFIG_ARCH_BUTTONS */

configs/nucleo-f303re/src/stm32_buttons.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * configs/nucleo-f303re/src/stm32_buttons.c
  *
- *   Copyright (C) 2014-2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2014-2015, 2017 Gregory Nutt. All rights reserved.
  *   Copyright (C) 2015 Omni Hoverboards Inc. All rights reserved.
  *   Authors: Gregory Nutt <gnutt@nuttx.org>
  *            Paul Alexander Patience <paul-a.patience@polymtl.ca>
@@ -120,13 +120,12 @@ uint8_t board_buttons(void)
  *   will be called when a button is depressed or released.  The ID value is
  *   a button enumeration value that uniquely identifies a button resource.
  *   See the BUTTON_* definitions in board.h for the meaning of the
- *   enumeration value.  The previous interrupt handler address is returned
- *   (so that it may be restored, if so desired).
+ *   enumeration value.
  *
  ****************************************************************************/
 
 #ifdef CONFIG_ARCH_IRQBUTTONS
-xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
+int board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 {
   xcpt_t oldhandler = NULL;
 
@@ -136,7 +135,8 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
                                       irqhandler, arg);
     }
 
-  return oldhandler;
+  UNUSED(oldhandler);
+  return OK;
 }
 #endif
 

configs/nucleo-f4x1re/src/stm32_buttons.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * configs/nucleo-f4x1re/src/stm32_buttons.c
  *
- *   Copyright (C) 2014-2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2014-2015, 2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -117,13 +117,12 @@ uint8_t board_buttons(void)
  *   be called when a button is depressed or released.  The ID value is a
  *   button enumeration value that uniquely identifies a button resource. See the
  *   BUTTON_* definitions in board.h for the meaning of enumeration
- *   value.  The previous interrupt handler address is returned (so that it may
- *   restored, if so desired).
+ *   value.
  *
  ************************************************************************************/
 
 #ifdef CONFIG_ARCH_IRQBUTTONS
-xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
+int board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 {
   xcpt_t oldhandler = NULL;
 
@@ -133,7 +132,8 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
                                       irqhandler, arg);
     }
 
-  return oldhandler;
+  UNUSED(oldhandler);
+  return OK;
 }
 #endif
 #endif /* CONFIG_ARCH_BUTTONS */

configs/nucleo-l476rg/src/stm32_buttons.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * configs/nucleo-l476rg/src/stm32_buttons.c
  *
- *   Copyright (C) 2014-2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2014-2015, 2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -117,13 +117,12 @@ uint8_t board_buttons(void)
  *   be called when a button is depressed or released.  The ID value is a
  *   button enumeration value that uniquely identifies a button resource. See the
  *   BUTTON_* definitions in board.h for the meaning of enumeration
- *   value.  The previous interrupt handler address is returned (so that it may
- *   restored, if so desired).
+ *   value.
  *
  ************************************************************************************/
 
 #ifdef CONFIG_ARCH_IRQBUTTONS
-xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
+int board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 {
   xcpt_t oldhandler = NULL;
 
@@ -133,7 +132,8 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
                                       irqhandler, arg);
     }
 
-  return oldhandler;
+  UNUSED(oldhandler);
+  return OK;
 }
 #endif
 #endif /* CONFIG_ARCH_BUTTONS */

configs/olimex-efm32g880f128-stk/src/efm32_buttons.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * configs/olimex-efm32g880f128-stk/src/efm32_buttons.c
  *
- *   Copyright (C) 2014-2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2014-2015, 2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -75,9 +75,6 @@
  ****************************************************************************/
 
 #if defined(CONFIG_EFM32_GPIO_IRQ) && defined(CONFIG_ARCH_IRQBUTTONS)
-#if 0 /* REVISIT -- See comments in board_button_irq() */
-static xcpt_t g_button_handlers[NUM_BUTTONS];
-#endif
 static const uint8_t g_button_irqs[NUM_BUTTONS];
 #endif
 
@@ -154,8 +151,7 @@ uint8_t board_buttons(void)
  * Description:
  *   This function may be called to register an interrupt handler that will
  *   be called when a button is depressed or released.  The ID value is one
- *   of the BUTTON* definitions provided above. The previous interrupt
- *   handler address is returned (so that it may restored, if so desired).
+ *   of the BUTTON* definitions provided above.
  *
  * Configuration Notes:
  *   Configuration CONFIG_EFM32_GPIO_IRQ must be selected to enable the
@@ -168,10 +164,8 @@ uint8_t board_buttons(void)
  ****************************************************************************/
 
 #if defined(CONFIG_EFM32_GPIO_IRQ) && defined(CONFIG_ARCH_IRQBUTTONS)
-xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
+int board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 {
-  xcpt_t oldhandler = NULL;
-
   if (id >=0 && id < NUM_BUTTONS)
     {
       irqstate_t flags;
@@ -182,19 +176,6 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 
       flags = enter_critical_section();
 
-      /* Get/set the old button handler
-       *
-       * REVISIT:  Keeping copies of the hander in RAM seems wasteful
-       * since the OS already has this information internally.
-       */
-
-#if 0 /* REVISIT */
-      oldhandler = g_button_handlers[id];
-      g_button_handlers[id] = irqhandler;
-#else
-      oldhandler = NULL;
-#endif
-
       /* Are we attaching or detaching? */
 
       if (irqhandler != NULL)
@@ -205,7 +186,7 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 
           /* Attach and enable the interrupt */
 
-          (void)irq_attach(g_button_irqs[id], irqhandler, NULL);
+          (void)irq_attach(g_button_irqs[id], irqhandler, arg);
           efm32_gpioirqenable(g_button_irqs[id]);
         }
       else
@@ -221,7 +202,7 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 
   /* Return the old button handler (so that it can be restored) */
 
-  return oldhandler;
+  return OK;
 }
 #endif
 

configs/olimex-lpc1766stk/src/lpc17_buttons.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * configs/olimex-lpc1766stk/src/lpc17_buttons.c
  *
- *   Copyright (C) 2011, 2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2011, 2015, 2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -70,13 +70,7 @@ static const uint16_t g_buttoncfg[BOARD_NUM_BUTTONS] =
   LPC1766STK_UP,   LPC1766STK_DOWN, LPC1766STK_LEFT,   LPC1766STK_RIGHT
 };
 
-/* This array defines all of the interrupt handlers current attached to
- * button events.
- */
-
 #if defined(CONFIG_ARCH_IRQBUTTONS) && defined(CONFIG_LPC17_GPIOIRQ)
-static xcpt_t g_buttonisr[BOARD_NUM_BUTTONS];
-
 /* This array provides the mapping from button ID numbers to button IRQ
  * numbers.
  */
@@ -171,8 +165,7 @@ uint8_t board_buttons(void)
  *   be called when a button is depressed or released.  The ID value is a
  *   button enumeration value that uniquely identifies a button resource. See the
  *   BOARD_BUTTON_* and BOARD_JOYSTICK_* definitions in board.h for the meaning
- *   of enumeration values.  The previous interrupt handler address is returned
- *   (so that it may restored, if so desired).
+ *   of enumeration values.
  *
  *   Note that board_button_irq() also enables button interrupts.  Button
  *   interrupts will remain enabled after the interrupt handler is attached.
@@ -182,9 +175,8 @@ uint8_t board_buttons(void)
  ****************************************************************************/
 
 #if defined(CONFIG_ARCH_IRQBUTTONS) && defined(CONFIG_LPC17_GPIOIRQ)
-xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
+int board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 {
-  xcpt_t oldhandler = NULL;
   irqstate_t flags;
   int irq;
 
@@ -192,11 +184,6 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 
   if ((unsigned)id < BOARD_NUM_BUTTONS)
     {
-      /* Return the current button handler and set the new interrupt handler */
-
-      oldhandler      = g_buttonisr[id];
-      g_buttonisr[id] = irqhandler;
-
       /* Disable interrupts until we are done */
 
       flags = enter_critical_section();
@@ -210,7 +197,7 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
         {
           /* Attach then enable the new interrupt handler */
 
-          (void)irq_attach(irq, irqhandler, NULL);
+          (void)irq_attach(irq, irqhandler, arg);
           up_enable_irq(irq);
         }
       else
@@ -220,9 +207,11 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
           up_disable_irq(irq);
           (void)irq_detach(irq);
         }
+
       leave_critical_section(flags);
     }
-  return oldhandler;
+
+  return OK;
 }
 #endif
 

configs/olimex-stm32-e407/src/stm32_buttons.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * configs/olimex-stm32-e407/src/stm32_buttons.c
  *
- *   Copyright (C) 2014-2016 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2014-2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -127,13 +127,12 @@ uint8_t board_buttons(void)
  *   will be called when a button is depressed or released.  The ID value is
  *   a button enumeration value that uniquely identifies a button resource.
  *   See the BUTTON_* definitions in board.h for the meaning of enumeration
- *   value.  The previous interrupt handler address is returned (so that it
- *   may restored, if so desired).
+ *   value.
  *
  ****************************************************************************/
 
 #ifdef CONFIG_ARCH_IRQBUTTONS
-xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
+int board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 {
   xcpt_t oldhandler = NULL;
 
@@ -145,7 +144,8 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
         stm32_gpiosetevent(g_buttons[id], true, true, true, irqhandler, arg);
     }
 
-  return oldhandler;
+  UNUSED(oldhandler);
+  return OK;
 }
 #endif
 #endif /* CONFIG_ARCH_BUTTONS */

configs/olimex-stm32-h405/src/stm32_buttons.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * configs/olimex-stm32-h405/src/stm32_buttons.c
  *
- *   Copyright (C) 2014-2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2014-2015, 2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -135,13 +135,12 @@ uint8_t board_buttons(void)
  *   be called when a button is depressed or released.  The ID value is a
  *   button enumeration value that uniquely identifies a button resource. See the
  *   BUTTON_* definitions in board.h for the meaning of enumeration
- *   value.  The previous interrupt handler address is returned (so that it may
- *   restored, if so desired).
+ *   value.
  *
  ************************************************************************************/
 
 #ifdef CONFIG_ARCH_IRQBUTTONS
-xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
+int board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 {
   xcpt_t oldhandler = NULL;
 
@@ -153,7 +152,8 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
                                       irqhandler, arg);
     }
 
-  return oldhandler;
+  UNUSED(oldhandler);
+  return OK;
 }
 #endif
 #endif /* CONFIG_ARCH_BUTTONS */

configs/olimex-stm32-h407/src/stm32_buttons.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * configs/olimex-stm32-h407/src/stm32_buttons.c
  *
- *   Copyright (C) 2014-2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2014-2015, 2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -127,13 +127,12 @@ uint8_t board_buttons(void)
  *   will be called when a button is depressed or released.  The ID value is
  *   a button enumeration value that uniquely identifies a button resource.
  *   See the BUTTON_* definitions in board.h for the meaning of enumeration
- *   value.  The previous interrupt handler address is returned (so that it
- *   may restored, if so desired).
+ *   value.
  *
  ****************************************************************************/
 
 #ifdef CONFIG_ARCH_IRQBUTTONS
-xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
+int board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 {
   xcpt_t oldhandler = NULL;
 
@@ -145,7 +144,8 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
                                       irqhandler, arg);
     }
 
-  return oldhandler;
+  UNUSED(oldhandler);
+  return OK;
 }
 #endif
 #endif /* CONFIG_ARCH_BUTTONS */

configs/olimex-stm32-p207/src/stm32_buttons.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * configs/olimex-stm32-p207/src/stm32_buttons.c
  *
- *   Copyright (C) 2011-2012, 2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2011-2012, 2015, 2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -171,13 +171,12 @@ uint8_t board_buttons(void)
  *   be called when a button is depressed or released.  The ID value is a
  *   button enumeration value that uniquely identifies a button resource. See the
  *   BUTTON_* definitions in board.h for the meaning of enumeration
- *   value.  The previous interrupt handler address is returned (so that it may
- *   restored, if so desired).
+ *   value.
  *
  ************************************************************************************/
 
 #ifdef CONFIG_ARCH_IRQBUTTONS
-xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
+int board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 {
   xcpt_t oldhandler = NULL;
 
@@ -189,7 +188,8 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
                                       irqhandler, arg);
     }
 
-  return oldhandler;
+  UNUSED(oldhandler);
+  return OK;
 }
 #endif
 #endif /* CONFIG_ARCH_BUTTONS */

configs/olimex-stm32-p407/src/stm32_buttons.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * configs/olimex-stm32-p407/src/stm32_buttons.c
  *
- *   Copyright (C) 2016 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2016-2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -165,13 +165,12 @@ uint8_t board_buttons(void)
  *   be called when a button is depressed or released.  The ID value is a
  *   button enumeration value that uniquely identifies a button resource. See the
  *   BUTTON_* definitions in board.h for the meaning of enumeration
- *   value.  The previous interrupt handler address is returned (so that it may
- *   restored, if so desired).
+ *   value.
  *
  ************************************************************************************/
 
 #ifdef CONFIG_ARCH_IRQBUTTONS
-xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
+int board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 {
   xcpt_t oldhandler = NULL;
 
@@ -183,7 +182,8 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
                                       irqhandler, arg);
     }
 
-  return oldhandler;
+  UNUSED(oldhandler);
+  return OK;
 }
 #endif
 #endif /* CONFIG_ARCH_BUTTONS */

configs/olimexino-stm32/src/stm32_buttons.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * configs/olimexino-stm32/src/stm32_buttons.c
  *
- *   Copyright (C) 2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2015, 2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *           David_s5 <david_s5@nscdg.com>
  *
@@ -80,8 +80,7 @@
  *   will be called when a button is depressed or released.  The ID value is
  *   a button enumeration value that uniquely identifies a button resource.
  *   See the BUTTON_* definitions in board.h for the meaning of enumeration
- *   value.  The previous interrupt handler address is returned
- *   (so that it may restored, if so desired).
+ *   value.
  *
  ****************************************************************************/
 
@@ -127,13 +126,12 @@ uint8_t board_buttons(void)
  *   will be called when a button is depressed or released.  The ID value is
  *   a button enumeration value that uniquely identifies a button resource.
  *   See the BUTTON_* definitions in board.h for the meaning of enumeration
- *   value.  The previous interrupt handler address is returned
- *   (so that it may restored, if so desired).
+ *   value.
  *
  ****************************************************************************/
 
 #ifdef CONFIG_ARCH_IRQBUTTONS
-xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
+int board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 {
   xcpt_t oldhandler = NULL;
 
@@ -145,7 +143,8 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
                                       irqhandler, arg);
     }
 
-  return oldhandler;
+  UNUSED(oldhandler);
+  return OK;
 }
 #endif
 #endif /* CONFIG_ARCH_BUTTONS */

configs/open1788/src/lpc17_buttons.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * configs/open1788/src/lpc17_buttons.c
  *
- *   Copyright (C) 2013, 2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2013, 2015, 2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -41,6 +41,7 @@
 
 #include <stdint.h>
 #include <stdbool.h>
+#include <errno.h>
 
 #include <nuttx/arch.h>
 #include <nuttx/board.h>
@@ -89,13 +90,7 @@ static const lpc17_pinset_t g_buttoncfg[BOARD_NUM_BUTTONS] =
   GPIO_JOY_B, GPIO_JOY_C, GPIO_JOY_D, GPIO_JOY_CTR
 };
 
-/* This array defines all of the interrupt handlers current attached to
- * button events.
- */
-
 #if defined(CONFIG_ARCH_IRQBUTTONS) && defined(CONFIG_LPC17_GPIOIRQ)
-static xcpt_t g_buttonisr[BOARD_NUM_BUTTONS];
-
 /* This array provides the mapping from button ID numbers to button IRQ
  * numbers.
  */
@@ -189,8 +184,7 @@ uint8_t board_buttons(void)
  *   be called when a button is depressed or released.  The ID value is a
  *   button enumeration value that uniquely identifies a button resource. See the
  *   BOARD_BUTTON_* and BOARD_JOYSTICK_* definitions in board.h for the meaning
- *   of enumeration values.  The previous interrupt handler address is returned
- *   (so that it may restored, if so desired).
+ *   of enumeration values.
  *
  *   Note that board_button_irq() also enables button interrupts.  Button
  *   interrupts will remain enabled after the interrupt handler is attached.
@@ -200,10 +194,10 @@ uint8_t board_buttons(void)
  ****************************************************************************/
 
 #if defined(CONFIG_ARCH_IRQBUTTONS) && defined(CONFIG_LPC17_GPIOIRQ)
-xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
+int board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 {
-  xcpt_t oldhandler = NULL;
   irqstate_t flags;
+  int ret = -EINVAL;
   int irq;
 
   /* Verify that the button ID is within range */
@@ -221,11 +215,6 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 
           flags = enter_critical_section();
 
-          /* Return the current button handler and set the new interrupt handler */
-
-          oldhandler      = g_buttonisr[id];
-          g_buttonisr[id] = irqhandler;
-
           /* Configure the interrupt.  Either attach and enable the new
            * interrupt or disable and detach the old interrupt handler.
            */
@@ -234,7 +223,7 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
             {
               /* Attach then enable the new interrupt handler */
 
-              (void)irq_attach(irq, irqhandler, NULL);
+              (void)irq_attach(irq, irqhandler, arg);
               up_enable_irq(irq);
             }
           else
@@ -247,9 +236,11 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 
           leave_critical_section(flags);
         }
+
+      ret = OK;
     }
 
-  return oldhandler;
+  return ret;
 }
 #endif
 

configs/pcduino-a10/src/a1x_buttons.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * configs/pcduino-a10/src/a1x_buttons.c
  *
- *   Copyright (C) 2013-2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2013-2015, 2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -40,6 +40,7 @@
 #include <nuttx/config.h>
 
 #include <stdint.h>
+#include <errno.h>
 
 #include <nuttx/arch.h>
 #include <nuttx/board.h>
@@ -52,22 +53,6 @@
 
 #ifdef CONFIG_ARCH_BUTTONS
 
-/****************************************************************************
- * Pre-processor Definitions
- ****************************************************************************/
-
-/****************************************************************************
- * Private Data
- ****************************************************************************/
-
-#ifdef CONFIG_ARCH_IRQBUTTONS
-static xcpt_t g_irqbutton[BOARD_NBUTTONS];
-#endif
-
-/****************************************************************************
- * Private Functions
- ****************************************************************************/
-
 /****************************************************************************
  * Public Functions
  ****************************************************************************/
@@ -110,8 +95,7 @@ uint8_t board_buttons(void)
  * Description:
  *   This function may be called to register an interrupt handler that will
  *   be called when a button is depressed or released.  The ID value is one
- *   of the BUTTON* definitions provided above. The previous interrupt
- *   handler address isreturned (so that it may restored, if so desired).
+ *   of the BUTTON* definitions provided above.
  *
  * Configuration Notes:
  *   Configuration CONFIG_ARCH_IRQBUTTONS must be selected to enable the
@@ -120,9 +104,9 @@ uint8_t board_buttons(void)
  ****************************************************************************/
 
 #ifdef CONFIG_ARCH_IRQBUTTONS
-xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
+int board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 {
-  xcpt_t oldhandler = NULL;
+  int ret = -EINVAL;
 
   if (id < BOARD_NBUTTONS)
     {
@@ -134,22 +118,17 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 
       flags = enter_critical_section();
 
-      /* Get the old button interrupt handler and save the new one */
-
-      oldhandler      = g_irqbutton[id];
-      g_irqbutton[id] = irqhandler;
-
       /* Configure the interrupt */
 
       a1x_pioirq(xxx);
       (void)irq_attach(xxx, irqhandler, NULL);
       a1x_pioirqenable(xxx);
       leave_critical_section(flags);
+
+      ret = OK;
     }
 
-  /* Return the old button handler (so that it can be restored) */
-
-  return oldhandler;
+  return ret;
 }
 #endif
 

configs/pic32mz-starterkit/src/pic32mz_buttons.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * configs/pic32mz-starterkit/src/pic32mz_buttons.c
  *
- *   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
@@ -40,6 +40,7 @@
 #include <nuttx/config.h>
 
 #include <stdint.h>
+#include <errno.h>
 
 #include <nuttx/arch.h>
 #include <nuttx/board.h>
@@ -146,13 +147,12 @@ uint8_t board_buttons(void)
  *   will be called when a button is depressed or released.  The ID value is
  *   a button enumeration value that uniquely identifies a button resource.
  *   See the BUTTON_* definitions in board.h for the meaning of enumeration
- *   value.  The previous interrupt handler address is returned (so that it
- *   may restored, if so desired).
+ *   value.
  *
  ****************************************************************************/
 
 #ifdef CONFIG_ARCH_IRQBUTTONS
-xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
+int board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 {
 #ifdef CONFIG_PIC32MZ_GPIOIRQ_PORTB
   int ret = OK;

configs/sam3u-ek/src/sam_buttons.c

@@ -170,8 +170,7 @@ uint8_t board_buttons(void)
  * Description:
  *   This function may be called to register an interrupt handler that will
  *   be called when a button is depressed or released.  The ID value is one
- *   of the BUTTON* definitions provided above. The previous interrupt
- *   handler address isreturned (so that it may restored, if so desired).
+ *   of the BUTTON* definitions provided above.
  *
  * Configuration Notes:
  *   Configuration CONFIG_AVR32_GPIOIRQ must be selected to enable the

configs/sam4e-ek/src/sam_buttons.c

@@ -176,8 +176,7 @@ uint8_t board_buttons(void)
  * Description:
  *   This function may be called to register an interrupt handler that will
  *   be called when a button is depressed or released.  The ID value is one
- *   of the BUTTON* definitions provided above. The previous interrupt
- *   handler address isreturned (so that it may restored, if so desired).
+ *   of the BUTTON* definitions provided above.
  *
  * Configuration Notes:
  *   Configuration CONFIG_AVR32_GPIOIRQ must be selected to enable the

configs/sam4l-xplained/src/sam_buttons.c

@@ -111,8 +111,7 @@ uint8_t board_buttons(void)
  * Description:
  *   This function may be called to register an interrupt handler that will
  *   be called when a button is depressed or released.  The ID value is one
- *   of the BUTTON* definitions provided above. The previous interrupt
- *   handler address is returned (so that it may restored, if so desired).
+ *   of the BUTTON* definitions provided above.
  *
  * Configuration Notes:
  *   Configuration CONFIG_AVR32_GPIOIRQ must be selected to enable the

configs/sam4s-xplained-pro/src/sam_buttons.c

@@ -110,8 +110,7 @@ uint8_t board_buttons(void)
  * Description:
  *   This function may be called to register an interrupt handler that will
  *   be called when a button is depressed or released.  The ID value is one
- *   of the BUTTON* definitions provided above. The previous interrupt
- *   handler address is returned (so that it may restored, if so desired).
+ *   of the BUTTON* definitions provided above.
  *
  * Configuration Notes:
  *   Configuration CONFIG_AVR32_GPIOIRQ must be selected to enable the

configs/sam4s-xplained/src/sam_buttons.c

@@ -111,8 +111,7 @@ uint8_t board_buttons(void)
  * Description:
  *   This function may be called to register an interrupt handler that will
  *   be called when a button is depressed or released.  The ID value is one
- *   of the BUTTON* definitions provided above. The previous interrupt
- *   handler address is returned (so that it may restored, if so desired).
+ *   of the BUTTON* definitions provided above.
  *
  * Configuration Notes:
  *   Configuration CONFIG_AVR32_GPIOIRQ must be selected to enable the

configs/sama5d2-xult/src/sam_buttons.c

@@ -122,8 +122,7 @@ uint8_t board_buttons(void)
  * Description:
  *   This function may be called to register an interrupt handler that will
  *   be called when a button is depressed or released.  The ID value is one
- *   of the BUTTON* definitions provided above. The previous interrupt
- *   handler address is returned (so that it may restored, if so desired).
+ *   of the BUTTON* definitions provided above.
  *
  * Configuration Notes:
  *   Configuration CONFIG_SAMA5_PIO_IRQ must be selected to enable the

configs/sama5d3-xplained/src/sam_buttons.c

@@ -126,8 +126,7 @@ uint8_t board_buttons(void)
  * Description:
  *   This function may be called to register an interrupt handler that will
  *   be called when a button is depressed or released.  The ID value is one
- *   of the BUTTON* definitions provided above. The previous interrupt
- *   handler address is returned (so that it may restored, if so desired).
+ *   of the BUTTON* definitions provided above.
  *
  * Configuration Notes:
  *   Configuration CONFIG_SAMA5_PIO_IRQ must be selected to enable the

configs/sama5d3x-ek/src/sam_buttons.c

@@ -126,8 +126,7 @@ uint8_t board_buttons(void)
  * Description:
  *   This function may be called to register an interrupt handler that will
  *   be called when a button is depressed or released.  The ID value is one
- *   of the BUTTON* definitions provided above. The previous interrupt
- *   handler address isreturned (so that it may restored, if so desired).
+ *   of the BUTTON* definitions provided above.
  *
  * Configuration Notes:
  *   Configuration CONFIG_SAMA5_PIO_IRQ must be selected to enable the

configs/sama5d4-ek/src/sam_buttons.c

@@ -122,8 +122,7 @@ uint8_t board_buttons(void)
  * Description:
  *   This function may be called to register an interrupt handler that will
  *   be called when a button is depressed or released.  The ID value is one
- *   of the BUTTON* definitions provided above. The previous interrupt
- *   handler address is returned (so that it may restored, if so desired).
+ *   of the BUTTON* definitions provided above.
  *
  * Configuration Notes:
  *   Configuration CONFIG_SAMA5_PIO_IRQ must be selected to enable the

configs/samd20-xplained/src/sam_buttons.c

@@ -111,8 +111,7 @@ uint8_t board_buttons(void)
  * Description:
  *   This function may be called to register an interrupt handler that will
  *   be called when a button is depressed or released.  The ID value is one
- *   of the BUTTON* definitions provided above. The previous interrupt
- *   handler address isreturned (so that it may restored, if so desired).
+ *   of the BUTTON* definitions provided above.
  *
  * Configuration Notes:
  *   Configuration CONFIG_AVR32_PORTIRQ must be selected to enable the

configs/samd21-xplained/src/sam_buttons.c

@@ -111,8 +111,7 @@ uint8_t board_buttons(void)
  * Description:
  *   This function may be called to register an interrupt handler that will
  *   be called when a button is depressed or released.  The ID value is one
- *   of the BUTTON* definitions provided above. The previous interrupt
- *   handler address isreturned (so that it may restored, if so desired).
+ *   of the BUTTON* definitions provided above.
  *
  * Configuration Notes:
  *   Configuration CONFIG_AVR32_PORTIRQ must be selected to enable the

configs/same70-xplained/src/sam_buttons.c

@@ -175,8 +175,7 @@ uint8_t board_buttons(void)
  * Description:
  *   This function may be called to register an interrupt handler that will
  *   be called when a button is depressed or released.  The ID value is one
- *   of the BUTTON* definitions provided above. The previous interrupt
- *   handler address is returned (so that it may restored, if so desired).
+ *   of the BUTTON* definitions provided above.
  *
  * Configuration Notes:
  *   Configuration CONFIG_AVR32_GPIOIRQ must be selected to enable the

configs/saml21-xplained/src/sam_buttons.c

@@ -111,8 +111,7 @@ uint8_t board_buttons(void)
  * Description:
  *   This function may be called to register an interrupt handler that will
  *   be called when a button is depressed or released.  The ID value is one
- *   of the BUTTON* definitions provided above. The previous interrupt
- *   handler address isreturned (so that it may restored, if so desired).
+ *   of the BUTTON* definitions provided above.
  *
  * Configuration Notes:
  *   Configuration CONFIG_AVR32_PORTIRQ must be selected to enable the

configs/samv71-xult/src/sam_buttons.c

@@ -195,8 +195,7 @@ uint8_t board_buttons(void)
  * Description:
  *   This function may be called to register an interrupt handler that will
  *   be called when a button is depressed or released.  The ID value is one
- *   of the BUTTON* definitions provided above. The previous interrupt
- *   handler address is returned (so that it may restored, if so desired).
+ *   of the BUTTON* definitions provided above.
  *
  * Configuration Notes:
  *   Configuration CONFIG_AVR32_GPIOIRQ must be selected to enable the

configs/shenzhou/src/stm32_buttons.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * configs/shenzhou/src/stm32_buttons.c
  *
- *   Copyright (C) 2012, 2014-2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2012, 2014-2015, 2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -150,13 +150,12 @@ uint8_t board_buttons(void)
  *   be called when a button is depressed or released.  The ID value is a
  *   button enumeration value that uniquely identifies a button resource. See the
  *   BUTTON_* and JOYSTICK_* definitions in board.h for the meaning of enumeration
- *   value.  The previous interrupt handler address is returned (so that it may
- *   restored, if so desired).
+ *   value.
  *
  ************************************************************************************/
 
 #ifdef CONFIG_ARCH_IRQBUTTONS
-xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
+int board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 {
   xcpt_t oldhandler = NULL;
 
@@ -167,7 +166,9 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
       oldhandler = stm32_gpiosetevent(g_buttons[id], true, true, true,
                                       irqhandler, arg);
     }
-  return oldhandler;
+
+  UNUSED(oldhandler);
+  return OK;
 }
 #endif
 #endif /* CONFIG_ARCH_BUTTONS */

configs/spark/src/stm32_buttons.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * configs/spark/src/stm32_buttons.c
  *
- *   Copyright (C) 2011-2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2011-2015, 2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -49,18 +49,6 @@
 
 #ifdef CONFIG_ARCH_BUTTONS
 
-/****************************************************************************
- * Pre-processor Definitions
- ****************************************************************************/
-
-/****************************************************************************
- * Private Data
- ****************************************************************************/
-
-/****************************************************************************
- * Private Functions
- ****************************************************************************/
-
 /****************************************************************************
  * Public Functions
  ****************************************************************************/
@@ -114,13 +102,12 @@ uint8_t board_buttons(void)
  *   be called when a button is depressed or released.  The ID value is a
  *   button enumeration value that uniquely identifies a button resource. See the
  *   BUTTON_* definitions in board.h for the meaning of enumeration
- *   value.  The previous interrupt handler address is returned (so that it may
- *   restored, if so desired).
+ *   value.
  *
  ************************************************************************************/
 
 #ifdef CONFIG_ARCH_IRQBUTTONS
-xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
+int board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 {
   xcpt_t oldhandler = NULL;
 
@@ -131,7 +118,8 @@ xcpt_t board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
       oldhandler = stm32_gpiosetevent(GPIO_BTN, true, true, true, irqhandler, arg);
     }
 
-  return oldhandler;
+  UNUSED(oldhandler);
+  return OK;
 }
 #endif
 #endif /* CONFIG_ARCH_BUTTONS */

configs/stm3210e-eval/src/stm32_buttons.c

@@ -155,8 +155,7 @@ uint8_t board_buttons(void)
  *   be called when a button is depressed or released.  The ID value is a
  *   button enumeration value that uniquely identifies a button resource. See the
  *   BUTTON_* and JOYSTICK_* definitions in board.h for the meaning of enumeration
- *   value.  The previous interrupt handler address is returned (so that it may
- *   restored, if so desired).
+ *   value.
  *
  ************************************************************************************/
 

configs/stm3220g-eval/src/stm32_buttons.c

@@ -151,8 +151,7 @@ uint8_t board_buttons(void)
  *   be called when a button is depressed or released.  The ID value is a
  *   button enumeration value that uniquely identifies a button resource. See the
  *   BUTTON_* definitions in board.h for the meaning of enumeration
- *   value.  The previous interrupt handler address is returned (so that it may
- *   restored, if so desired).
+ *   value.
  *
  ************************************************************************************/
 

configs/stm3240g-eval/src/stm32_buttons.c

@@ -151,8 +151,7 @@ uint8_t board_buttons(void)
  *   be called when a button is depressed or released.  The ID value is a
  *   button enumeration value that uniquely identifies a button resource. See the
  *   BUTTON_* definitions in board.h for the meaning of enumeration
- *   value.  The previous interrupt handler address is returned (so that it may
- *   restored, if so desired).
+ *   value.
  *
  ************************************************************************************/
 

configs/stm32f103-minimum/src/stm32_buttons.c

@@ -146,8 +146,7 @@ uint8_t board_buttons(void)
  *   will be called when a button is depressed or released.  The ID value is
  *   a button enumeration value that uniquely identifies a button resource.
  *   See the BUTTON_* definitions in board.h for the meaning of enumeration
- *   value.  The previous interrupt handler address is returned (so that it
- *   may be restored, if so desired).
+ *   value.
  *
  ****************************************************************************/