arch/arm/src/lpc54xx: Fix some GPIO interrupt configuration errors. Add logic to acknowledge rising/falling edge events. config/lpcxpresso-lpc545628: Add an intermediate interrupt handler to support acknowledgement of rising and falling edge interrupts.

arch/arm/src/lpc54xx/lpc54_gpio.h

@@ -148,10 +148,10 @@
 #define GPIO_IS_INTR(ps)        (((uint32_t)(ps) & GPIO_INTR_MASK) == GPIO_INTR_CODE)
 
 #define GPIO_TRIG_MASK          (0x18 << GPIO_FUNC_SHIFT)  /* 111xx */
-#define GPIO_TRIG_LEVEL_CODE    (0x08 << GPIO_FUNC_SHIFT)  /* 010xx */
+#define GPIO_TRIG_EDGE_CODE     (0x08 << GPIO_FUNC_SHIFT)  /* 010xx */
-#define GPIO_TRIG_EDGE_CODE     (0x0c << GPIO_FUNC_SHIFT)  /* 011xx */
+#define GPIO_TRIG_LEVEL_CODE    (0x0c << GPIO_FUNC_SHIFT)  /* 011xx */
-#define GPIO_IS_INTLEVEL(ps)    (((uint32_t)(ps) & GPIO_TRIG_MASK) == GPIO_TRIG_LEVEL_CODE)
 #define GPIO_IS_INTEDGE(ps)     (((uint32_t)(ps) & GPIO_TRIG_MASK) == GPIO_TRIG_EDGE_CODE)
+#define GPIO_IS_INTLEVEL(ps)    (((uint32_t)(ps) & GPIO_TRIG_MASK) == GPIO_TRIG_LEVEL_CODE)
 
 #define GPIO_ALT_MASK           (0x18 << GPIO_FUNC_SHIFT)  /* 11xxx */
 #define GPIO_ALT_CODE           (0x10 << GPIO_FUNC_SHIFT)  /* 10xxx */
@@ -308,6 +308,20 @@ int lpc54_gpio_interrupt(lpc54_pinset_t pinset);
 int lpc54_gpio_irqno(lpc54_pinset_t pinset);
 #endif
 
+/************************************************************************************
+ * Name: lpc54_gpio_ackedge
+ *
+ * Description:
+ *   Acknowledge edge interrupts by clearing the associated bits in the rising and
+ *   falling registers.  This acknowledgemment is, of course, not needed for level
+ *   interupts.
+ *
+ ************************************************************************************/
+
+#ifdef CONFIG_LPC54_GPIOIRQ
+int lpc54_gpio_ackedge(int irq);
+#endif
+
 /************************************************************************************
  * Name: lpc54_gpio_write
  *

arch/arm/src/lpc54xx/lpc54_gpioirq.c

@@ -243,7 +243,7 @@ int lpc54_gpio_interrupt(lpc54_pinset_t pinset)
       /* Write to CIENR to disable rising-edge or level interrupts */
 
       case GPIO_INTFE:    /* GPIO interrupt falling edge */
-        putreg32(mask, LPC54_PINT_SIENR);
+        putreg32(mask, LPC54_PINT_CIENR);
         break;
 
       default:
@@ -260,7 +260,7 @@ int lpc54_gpio_interrupt(lpc54_pinset_t pinset)
       case GPIO_INTFE:    /* GPIO interrupt falling edge */
       case GPIO_INTBOTH:  /* GPIO interrupt both edges */
       case GPIO_INTHIGH:  /* GPIO interrupt high level */
-        putreg32(mask, LPC54_PINT_SIENR);
+        putreg32(mask, LPC54_PINT_SIENF);
         break;
 
       /* Write to CIENF to disable falling-edge or enable active-low level
@@ -269,7 +269,7 @@ int lpc54_gpio_interrupt(lpc54_pinset_t pinset)
 
       case GPIO_INTRE:    /* GPIO interrupt rising edge */
       case GPIO_INTLOW:   /* GPIO interrupt low level */
-        putreg32(mask, LPC54_PINT_SIENR);
+        putreg32(mask, LPC54_PINT_CIENF);
         break;
 
       default:
@@ -317,4 +317,46 @@ int lpc54_gpio_irqno(lpc54_pinset_t pinset)
   return -ENOENT;
 }
 
+/************************************************************************************
+ * Name: lpc54_gpio_ackedge
+ *
+ * Description:
+ *   Acknowledge edge interrupts by clearing the associated bits in the rising and
+ *   falling registers.  This acknowledgemment is, of course, not needed for level
+ *   interupts.
+ *
+ ************************************************************************************/
+
+int lpc54_gpio_ackedge(int irq)
+{
+  uint32_t regval;
+  uint32_t mask;
+  unsigned int pinint;
+
+  /* Map the IRQ number to a pin interrupt number */
+
+  if (irq >= LPC54_IRQ_PININT0 && irq <= LPC54_IRQ_PININT3)
+    {
+      pinint = irq - LPC54_IRQ_PININT0;
+    }
+  else if (irq >= LPC54_IRQ_PININT4 && irq <= LPC54_IRQ_PININT7)
+    {
+      pinint = irq - LPC54_IRQ_PININT4 + 4;
+    }
+  else
+    {
+      return -EINVAL;
+    }
+
+  /* Acknowledge the pin interrupt */
+
+  mask   = (1 << pinint);
+  regval = getreg32(LPC54_PINT_RISE) & mask;
+  putreg32(regval, LPC54_PINT_RISE);
+
+  regval = getreg32(LPC54_PINT_FALL) & mask;
+  putreg32(regval, LPC54_PINT_FALL);
+  return OK;
+}
+
 #endif /* CONFIG_LPC54_GPIOIRQ */

configs/lpcxpresso-lpc54628/README.txt

@@ -51,8 +51,12 @@ STATUS
     The I2C driver appears to be functional but is not yet well-tested.
   2017-12-16:  Added support for LPC54xx GPIO interrupts; added button
     support (with interrupts) to the NSH configuration.  The button
-    test is partially functional but appears to miss a lot of button-
+    test appears to functional functional.  There are noticeable delays
-    related events.  More testing is needed.
+    in receiving the button events, especially when the button is
+    released.  But if you do not press the buttons too quickly all events
+    are processed.  This, I suspect, is a consequence of the strong glitch
+    filtering that is enbled in the pin configuration.  Snappier
+    response my be obtainble with filtering off.
 
 Configurations
 ==============
@@ -226,3 +230,26 @@ Configurations
     4. Support for the on-board USER button is included as well as the
        button test program at apps/examples/buttons.  This test is useful
        for verifying the functionality of GPIO interrupts.
+
+         NuttShell (NSH) NuttX-7.23
+         nsh> buttons
+         buttons_main: Starting the button_daemon
+         buttons_main: button_daemon started
+         button_daemon: Running
+         button_daemon: Opening /dev/buttons
+         button_daemon: Supported BUTTONs 0x01
+         nsh> Sample = 1
+         Sample = 0
+         Sample = 1
+         Sample = 0
+         Sample = 1
+         Sample = 0
+         Sample = 1
+         etc.
+
+       There are noticeable delays in receiving the button events,
+       especially when the button is released.  But if you do not press the
+       buttons too quickly all events are processed.  This, I suspect, is a
+       consequence of the strong glitch filtering that is enbled in the pin
+       configuration.  Snappier response my be obtainble with filtering off
+       if desired.

configs/lpcxpresso-lpc54628/src/lpc54_buttons.c

@@ -55,6 +55,46 @@
 
 #ifdef CONFIG_ARCH_BUTTONS
 
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+#if defined(CONFIG_LPC54_GPIOIRQ) && defined(CONFIG_ARCH_IRQBUTTONS)
+static uint8_t g_button_irq;
+static xcpt_t  g_button_handler;
+static void   *g_button_arg;
+#endif
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: board_button_interrupt
+ *
+ * Description:
+ *   This function intermediates the interrupt provided to the application
+ *   logic that attached the interrupt.  This is necessary to properly
+ *   clear the pending button interrupts.
+ *
+ ****************************************************************************/
+
+static int board_button_interrupt(int irq, FAR void *context, FAR void *arg)
+{
+  /* Acknowledge the button interrupt */
+
+  (void)lpc54_gpio_ackedge(irq);
+
+  /* Transfer control to the attached interrupt handler */
+
+  if (g_button_handler != NULL)
+    {
+      return g_button_handler(irq, context, arg);
+    }
+
+  return OK;
+}
+
 /****************************************************************************
  * Public Functions
  ****************************************************************************/
@@ -72,7 +112,22 @@
 
 void board_button_initialize(void)
 {
-  (void)lpc54_gpio_config(GPIO_BUTTON_USER);
+  int ret;
+
+  /* Configure the button GPIO interrupt */
+
+  ret = lpc54_gpio_config(GPIO_BUTTON_USER);
+  if (ret >= 0)
+    {
+#if defined(CONFIG_LPC54_GPIOIRQ) && defined(CONFIG_ARCH_IRQBUTTONS)
+      /* Get the IRQ that is associated with the PIN interrupt and attach the
+       * intermediate button interrupt handler to that interrupt.
+       */
+
+      g_button_irq = lpc54_gpio_irqno(GPIO_BUTTON_USER);
+      (void)irq_attach(g_button_irq, board_button_interrupt, NULL);
+#endif
+    }
 }
 
 /****************************************************************************
@@ -115,35 +170,26 @@ int board_button_irq(int id, xcpt_t irqhandler, FAR void *arg)
 
   if (id == BUTTON_USER)
     {
-      int irq;
-
-      /* Get the IRQ number assigned to the port/pin when it was condfigured. */
-
-      irq = lpc54_gpio_irqno(GPIO_BUTTON_USER);
-      if (irq < 0)
-        {
-          return irq;
-        }
-
       /* Are we attaching or detaching? */
 
       if (irqhandler != NULL)
         {
           /* Yes.. Attach and enable the interrupt */
 
-          ret = irq_attach(irq, irqhandler, arg);
+          g_button_handler = irqhandler;
-          if (ret >= 0)
+          g_button_arg     = arg;
-            {
+          up_enable_irq(g_button_irq);
-              up_enable_irq(irq);
-            }
         }
       else
         {
           /* No.. Disable and detach the interrupt */
 
-          up_disable_irq(irq);
+          up_disable_irq(g_button_irq);
-          ret = irq_detach(irq);
+          g_button_handler = NULL;
+          g_button_arg     = NULL;
         }
+
+      ret = OK;
     }
 
   return ret;