Use a dedicated module for GPIO measurements.

coupler/gpio.h

+#include <linux/gpio.h>
+
+// the current GPI state (used for debuging)
+static unsigned int CURRENT_GPIO_STATE = 0;
+
+/*
+*  variable representing the measurement mode over GPIO
+*  0: disabled
+*  1: enabled for keep-alive subsystem
+*  2: enabled for first i2c0.relay0
+*/
+static unsigned int CURRENT_GPIO_MODE = 0;
+
+static int setGPIO() {
+  /*
+   * Set GPIO state (useful for debuging with logical analyzer)
+   */
+  int fd;
+  struct gpiohandle_request led;
+  struct gpiohandle_data data;
+
+  /* Schema for STMP15x-Shield
+   * GND         : pin 2
+   * Channel 0   : pin 9
+   */
+
+  fd = open("/dev/gpiochip1", O_RDWR);
+  if(fd < 0) {
+    perror("Error opening gpiochip");
+    return -1;
+  }
+
+  /* Setup GPIO to output */
+  led.flags = GPIOHANDLE_REQUEST_OUTPUT;
+  strcpy(led.consumer_label, "LED");
+  memset(led.default_values, 0, sizeof(led.default_values));
+  led.lines = 1;
+  led.lineoffsets[0] = 7;
+
+  if(ioctl(fd, GPIO_GET_LINEHANDLE_IOCTL, &led) < 0) {
+    perror("Error setting GPIO to output");
+    close(fd);
+    return -1;
+  }
+
+  // revert previous state
+  if (CURRENT_GPIO_STATE) CURRENT_GPIO_STATE = 0;
+  else CURRENT_GPIO_STATE = 1;
+
+  // set actual GPI value
+  data.values[0] = CURRENT_GPIO_STATE;
+  if(ioctl(led.fd, GPIOHANDLE_SET_LINE_VALUES_IOCTL, &data) < 0)
+    perror("Error setting GPIO to 1");
+
+  close(fd);
+  close(led.fd);
+  return 0;
+}
+
+

coupler/keep_alive.h

@@ -17,17 +17,6 @@ const int STATE_NO_INITIAL_HEART_BEAT = 2;
 // number of times the coupler was in SAFE mode 
 static unsigned int SAFE_MODE_STATE_COUNTER = 0;
 
-// the current GPI state (used for debuging)
-static unsigned int CURRENT_GPIO_STATE = 0;
-
-/*
-*  variable representing the measurement mode over GPIO
-*  0: disabled
-*  1: enabled for keep-alive subsystem
-*  2: enabled for first i2c0.relay0
-*/
-static unsigned int CURRENT_GPIO_MODE = 0;
-
 // the heart beat interval (in ms)
 const int DEFAULT_HEART_BEAT_INTERVAL = 250;
 static int HEART_BEAT_INTERVAL = DEFAULT_HEART_BEAT_INTERVAL;
@@ -36,7 +25,7 @@ static int HEART_BEAT_INTERVAL = DEFAULT_HEART_BEAT_INTERVAL;
 const int DEFAULT_HEART_BEAT_TIMEOUT_INTERVAL = 4 * DEFAULT_HEART_BEAT_INTERVAL;
 static int HEART_BEAT_TIMEOUT_INTERVAL = DEFAULT_HEART_BEAT_TIMEOUT_INTERVAL;
 
-// the list of couplers onto which we depend for properly running$
+// the list of couplers onto which we depend for properly running
 // XXX: assume ONLY 8 couplers!
 unsigned int HEART_BEAT_ID_LIST[] = {0, 0, 0, 0, 0, 0, 0, 0};
 

coupler/keep_alive_publisher.h

@@ -2,8 +2,6 @@
 Keep alive implementation for couplers based on OPC UA's pub/sub mechanism
 */
 
-#include "keep_alive.h"
-
 UA_NodeId connectionIdent, publishedDataSetIdent, writerGroupIdent;
 
 static void addPubSubConnection(UA_Server *server, UA_String *transportProfile,

coupler/keep_alive_subscriber.h

@@ -11,7 +11,6 @@
 #include <unistd.h>
 #include <fcntl.h>
 #include <sys/ioctl.h>
-#include <linux/gpio.h>
 
 UA_NodeId connectionIdentifier;
 UA_NodeId readerGroupIdentifier;
@@ -20,52 +19,6 @@ UA_DataSetReaderConfig readerConfig;
 
 static void fillTestDataSetMetaData(UA_DataSetMetaDataType *pMetaData);
 
-static int setGPIO() {
-  /*
-   * Set GPIO state (useful for debuging with logical analyzer
-   */
-  int fd;
-  struct gpiohandle_request led;
-  struct gpiohandle_data data;
-
-  /* Schema for STMP15x-Shield
-   * GND         : pin 2
-   * Channel 0   : pin 9
-   */
-
-  fd = open("/dev/gpiochip1", O_RDWR);
-  if(fd < 0) {
-    perror("Error opening gpiochip");
-    return -1;
-  }
-
-  /* Setup GPIO to output */
-  led.flags = GPIOHANDLE_REQUEST_OUTPUT;
-  strcpy(led.consumer_label, "LED");
-  memset(led.default_values, 0, sizeof(led.default_values));
-  led.lines = 1;
-  led.lineoffsets[0] = 7;
-
-  if(ioctl(fd, GPIO_GET_LINEHANDLE_IOCTL, &led) < 0) {
-    perror("Error setting GPIO to output");
-    close(fd);
-    return -1;
-  }
-
-  // revert previous state
-  if (CURRENT_GPIO_STATE) CURRENT_GPIO_STATE = 0;
-  else CURRENT_GPIO_STATE = 1;
-
-  // set actual GPI value
-  data.values[0] = CURRENT_GPIO_STATE;
-  if(ioctl(led.fd, GPIOHANDLE_SET_LINE_VALUES_IOCTL, &data) < 0)
-    perror("Error setting GPIO to 1");
-
-  close(fd);
-  close(led.fd);
-  return 0;
-}
-
 /* callback to handle change notifications */
 static void dataChangeNotificationCallback(UA_Server *server, UA_UInt32 monitoredItemId,
                                void *monitoredItemContext, const UA_NodeId *nodeId,

coupler/server.c

@@ -53,6 +53,8 @@ char *PASSWORD;
 char *X509_KEY_FILENAME;
 char *X509_CERTIFICATE_FILENAME;
 
+#include "gpio.h"
+#include "keep_alive.h"
 #include "keep_alive_publisher.h"
 #include "keep_alive_subscriber.h"
 #include "cli.h"