EFM32: Add buton interrupt handling for the Olimex board

5 files changed, 306 insertions, 25 deletions

diff --git a/nuttx/configs/olimex-efm32g880f128-stk/README.txt b/nuttx/configs/olimex-efm32g880f128-stk/README.txt
index f21bdb5db..9611a9ab1 100644
--- a/nuttx/configs/olimex-efm32g880f128-stk/README.txt
+++ b/nuttx/configs/olimex-efm32g880f128-stk/README.txt
@@ -46,6 +46,22 @@ LEDs
 
   The EFM32G880F128-STK has no user controllable LEDs.
 
+Buttons
+=======
+
+  The Olimex board has four buttons, BUT1-4.  Each is grounded and so should
+  have a weak pull-up so that it will be sensed as "1" when open and "0"
+  when closed.
+
+  --------------------- ---------------------
+  PIN                   CONNECTIONS
+  --------------------- ---------------------
+  PE0/PCNT0_S0IN/U0_TX  BUT1, EXT-18
+  PE1/PCNT0_S1IN/U0_RX  BUT2, EXT-19
+  PE2/ACMP0_O           BUT3, EXT-20
+  E3/ACMP1_O            BUT4, EXT-21
+  --------------------- ---------------------
+
 Serial Console
 ==============
 
diff --git a/nuttx/configs/olimex-efm32g880f128-stk/include/board.h b/nuttx/configs/olimex-efm32g880f128-stk/include/board.h
index d8c70fe98..45fd4fa15 100644
--- a/nuttx/configs/olimex-efm32g880f128-stk/include/board.h
+++ b/nuttx/configs/olimex-efm32g880f128-stk/include/board.h
@@ -204,6 +204,32 @@
 #define LED_ASSERTION     6  /* LED1 + LED2 + LED3 */
 #define LED_PANIC         7  /* N/C  + N/C  + N/C + LED4 */
 
+/* Buttons ******************************************************************/
+/* The Olimex board has four buttons, BUT1-4.  Each is grounded and so should
+ * have a weak pull-up so that it will be sensed as "1" when open and "0"
+ * when closed.
+ *
+ * --------------------- ---------------------
+ * PIN                   CONNECTIONS
+ * --------------------- ---------------------
+ * PE0/PCNT0_S0IN/U0_TX  BUT1, EXT-18
+ * PE1/PCNT0_S1IN/U0_RX  BUT2, EXT-19
+ * PE2/ACMP0_O           BUT3, EXT-20
+ * PE3/ACMP1_O           BUT4, EXT-21
+ * --------------------- ---------------------
+ */
+
+#define BUTTON_1          0
+#define BUTTON_2          1
+#define BUTTON_3          2
+#define BUTTON_4          3
+#define NUM_BUTTONS       4
+
+#define BUTTON_1_BIT  (1 << BUTTON_1)
+#define BUTTON_2_BIT  (1 << BUTTON_2)
+#define BUTTON_3_BIT  (1 << BUTTON_3)
+#define BUTTON_4_BIT  (1 << BUTTON_4)
+
 /* Pin routing **************************************************************/
 /* UART0:
  *
diff --git a/nuttx/configs/olimex-efm32g880f128-stk/src/Makefile b/nuttx/configs/olimex-efm32g880f128-stk/src/Makefile
index bd927233d..6428fdddf 100644
--- a/nuttx/configs/olimex-efm32g880f128-stk/src/Makefile
+++ b/nuttx/configs/olimex-efm32g880f128-stk/src/Makefile
@@ -37,6 +37,10 @@
 
 CSRCS = efm32_boot.c
 
+ifeq ($(CONFIG_ARCH_BUTTONS),y)
+CSRCS += efm32_buttons.c
+endif
+
 COBJS = $(CSRCS:.c=$(OBJEXT))
 SRCS = $(ASRCS) $(CSRCS)
 OBJS = $(AOBJS) $(COBJS)
diff --git a/nuttx/configs/olimex-efm32g880f128-stk/src/efm32_buttons.c b/nuttx/configs/olimex-efm32g880f128-stk/src/efm32_buttons.c
new file mode 100644
index 000000000..178bc2b9f
--- /dev/null
+++ b/nuttx/configs/olimex-efm32g880f128-stk/src/efm32_buttons.c
@@ -0,0 +1,227 @@
+/****************************************************************************
+ * configs/olimex-efm32g880f128-stk/src/efm32_buttons.c
+ *
+ *   Copyright (C) 2014 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+/* The Olimex board has four buttons, BUT1-4.  Each is grounded and so should
+ * have a weak pull-up so that it will be sensed as "1" when open and "0"
+ * when closed.
+ *
+ * --------------------- ---------------------
+ * PIN                   CONNECTIONS
+ * --------------------- ---------------------
+ * PE0/PCNT0_S0IN/U0_TX  BUT1, EXT-18
+ * PE1/PCNT0_S1IN/U0_RX  BUT2, EXT-19
+ * PE2/ACMP0_O           BUT3, EXT-20
+ * E3/ACMP1_O            BUT4, EXT-21
+ * --------------------- ---------------------
+ */
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <stdint.h>
+
+#include <nuttx/arch.h>
+#include <nuttx/irq.h>
+
+#include <arch/irq.h>
+#include <arch/board/board.h>
+
+#include "efm32_gpio.h"
+#include "efm32g880f128-stk.h"
+
+#if CONFIG_ARCH_BUTTONS
+
+/****************************************************************************
+ * Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+#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
+
+static const gpio_pinset_t g_button_configs[NUM_BUTTONS] =
+{
+  GPIO_BUTTON_1, GPIO_BUTTON_2, GPIO_BUTTON_3, GPIO_BUTTON_4
+};
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: board_button_initialize
+ *
+ * Description:
+ *   board_button_initialize() must be called to initialize button resources.
+ *   After that, board_buttons() may be called to collect the current state
+ *   of all buttons or board_button_irq() may be called to register button
+ *   interrupt handlers.
+ *
+ ****************************************************************************/
+
+void board_button_initialize(void)
+{
+  int i;
+
+  /* Configure each button */
+
+  for (i = 0; i < NUM_BUTTONS; i++)
+    {
+      (void)efm32_configgpio(g_button_configs[i]);
+    }
+}
+
+/****************************************************************************
+ * Name: board_buttons
+ *
+ * Description:
+ *   After board_button_initialize() has been called, board_buttons() may be
+ *   called to collect the state of all buttons.  board_buttons() returns an
+ *   8-bit bit set with each bit associated with a button.  See the BUTTON*
+ *   definitions above for the meaning of each bit in the returned value.
+ *
+ ****************************************************************************/
+
+uint8_t board_buttons(void)
+{
+  uint8_t ret;
+  int i;
+
+  /* Check each button */
+
+  for (i = 0, ret = 0; i < NUM_BUTTONS; i++)
+    {
+      /* The button is closed if a low value is sensed */
+
+      if (!efm32_gpioread(g_button_configs[i]))
+        {
+          ret |= (1 << i);
+        }
+    }
+
+  return ret;
+}
+
+/****************************************************************************
+ * Name: board_button_irq
+ *
+ * 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).
+ *
+ * Configuration Notes:
+ *   Configuration CONFIG_EFM32_GPIO_IRQ must be selected to enable the
+ *   overall GPIO IRQ feature.
+ *
+ * Returned Value:
+ *   This function should return the old interrupt handler value, but
+ *   currently always returns NULL.
+ *
+ ****************************************************************************/
+
+#if defined(CONFIG_EFM32_GPIO_IRQ) && defined(CONFIG_ARCH_IRQBUTTONS)
+xcpt_t board_button_irq(int id, xcpt_t irqhandler)
+{
+  xcpt_t oldhandler = NULL;
+
+  if (id >=0 && id < NUM_BUTTONS)
+    {
+      irqstate_t flags;
+
+      /* Disable interrupts until we are done.  This guarantees that the
+       * following operations are atomic.
+       */
+
+      flags = irqsave();
+
+      /* 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)
+        {
+          /* Configure the interrupt */
+
+          efm32_gpioirq(g_button_configs[id]);
+
+          /* Attach and enable the interrupt */
+
+          (void)irq_attach(g_button_irqs[id], irqhandler);
+          efm32_gpioirqenable(g_button_irqs[id]);
+        }
+      else
+        {
+          /* Disable and detach the interrupt */
+
+          efm32_gpioirqdisable(g_button_irqs[id]);
+          (void)irq_detach(g_button_irqs[id]);
+        }
+
+      irqrestore(flags);
+    }
+
+  /* Return the old button handler (so that it can be restored) */
+
+  return oldhandler;
+}
+#endif
+
+#endif /* CONFIG_ARCH_BUTTONS */
diff --git a/nuttx/configs/olimex-efm32g880f128-stk/src/efm32g880f128-stk.h b/nuttx/configs/olimex-efm32g880f128-stk/src/efm32g880f128-stk.h
index f70344acc..ebd0bab9d 100644
--- a/nuttx/configs/olimex-efm32g880f128-stk/src/efm32g880f128-stk.h
+++ b/nuttx/configs/olimex-efm32g880f128-stk/src/efm32g880f128-stk.h
@@ -40,36 +40,44 @@
  * Included Files
  ****************************************************************************/
 
+#include <arch/irq.h>
+
 /****************************************************************************
  * Pre-processor Definitions
  ****************************************************************************/
 
- /* LEDs
-  *
-  * The EFM32 Gecko Start Kit has four yellow LEDs.  These LEDs are connected
-  * as follows:
-  *
-  *   ------------------------------------- --------------------
-  *   EFM32 PIN                             BOARD SIGNALS
-  *   ------------------------------------- --------------------
-  *   C0/USART1_TX#0/PCNT0_S0IN#2/ACMP0_CH0  MCU_PC0  UIF_LED0
-  *   C1/USART1_RX#0/PCNT0_S1IN#2/ACMP0_CH1  MCU_PC1  UIF_LED1
-  *   C2/USART2_TX#0/ACMP0_CH2               MCU_PC2  UIF_LED2
-  *   C3/USART2_RX#0/ACMP0_CH3               MCU_PC3  UIF_LED3
-  *   ------------------------------------- --------------------
-  *
-  * All LEDs are grounded and so are illuminated by outputting a high
-  * value to the LED.
-  */
+/* Buttons:
+ *
+ * The Olimex board has four buttons, BUT1-4.  Each is grounded and so should
+ * have a weak pull-up so that it will be sensed as "1" when open and "0"
+ * when closed.
+ *
+ * --------------------- ---------------------
+ * PIN                   CONNECTIONS
+ * --------------------- ---------------------
+ * PE0/PCNT0_S0IN/U0_TX  BUT1, EXT-18
+ * PE1/PCNT0_S1IN/U0_RX  BUT2, EXT-19
+ * PE2/ACMP0_O           BUT3, EXT-20
+ * PE3/ACMP1_O           BUT4, EXT-21
+ * --------------------- ---------------------
+ */
+
+#ifdef CONFIG_EFM32_GPIO_IRQ
+#  define GPIO_BUTTON_1 (GPIO_INPUT_PULLUP|GPIO_INT_BOTH|GPIO_PORTE|GPIO_PIN0)
+#  define GPIO_BUTTON_2 (GPIO_INPUT_PULLUP|GPIO_INT_BOTH|GPIO_PORTE|GPIO_PIN1)
+#  define GPIO_BUTTON_3 (GPIO_INPUT_PULLUP|GPIO_INT_BOTH|GPIO_PORTE|GPIO_PIN2)
+#  define GPIO_BUTTON_4 (GPIO_INPUT_PULLUP|GPIO_INT_BOTH|GPIO_PORTE|GPIO_PIN3)
 
-#define GPIO_LED1       (GPIO_OUTPUT_WIREDOR_PULLDOWN|\
-                         GPIO_OUTPUT_CLEAR|GPIO_PORTC|GPIO_PIN0)
-#define GPIO_LED2       (GPIO_OUTPUT_WIREDOR_PULLDOWN|\
-                         GPIO_OUTPUT_CLEAR|GPIO_PORTC|GPIO_PIN1)
-#define GPIO_LED3       (GPIO_OUTPUT_WIREDOR_PULLDOWN|\
-                         GPIO_OUTPUT_CLEAR|GPIO_PORTC|GPIO_PIN2)
-#define GPIO_LED4       (GPIO_OUTPUT_WIREDOR_PULLDOWN|\
-                         GPIO_OUTPUT_CLEAR|GPIO_PORTC|GPIO_PIN3)
+#  define GPIO_IRQ_BUTTON_1 EFM32_IRQ_EXTI0
+#  define GPIO_IRQ_BUTTON_2 EFM32_IRQ_EXTI1
+#  define GPIO_IRQ_BUTTON_3 EFM32_IRQ_EXTI2
+#  define GPIO_IRQ_BUTTON_4 EFM32_IRQ_EXTI3
+#else
+#  define GPIO_BUTTON_1 (GPIO_INPUT_PULLUP|GPIO_PORTE|GPIO_PIN0)
+#  define GPIO_BUTTON_2 (GPIO_INPUT_PULLUP|GPIO_PORTE|GPIO_PIN1)
+#  define GPIO_BUTTON_3 (GPIO_INPUT_PULLUP|GPIO_PORTE|GPIO_PIN2)
+#  define GPIO_BUTTON_4 (GPIO_INPUT_PULLUP|GPIO_PORTE|GPIO_PIN3)
+#endif
 
 /****************************************************************************
  * Public Function Prototypes