Add interrupts to SPIDEV

Interrupt functionality is exactly the same as with BCM lib

Makefile

@@ -66,7 +66,8 @@ CCFLAGS=-Ofast -mfpu=vfp -mfloat-abi=hard -march=$(ARCH) -mtune=arm1176jzf-s
 
 else
 DRIVER_DIR=$(ARCH_DIR)/BBB
-OBJECTS+=gpio.o compatibility.o
+OBJECTS+=gpio.o compatibility.o interrupt.o
+SHARED_LINKER_FLAGS+=-pthread
 endif
 
 

utility/BBB/includes.h

@@ -4,5 +4,6 @@
 
   #define RF24_BBB
   #include "BBB/RF24_arch_config.h"
+  #include "BBB/interrupt.h"
   
 #endif
\ No newline at end of file

utility/BBB/interrupt.c

+/*
+Interrupts functions extruded from wiringPi library by Oitzu.
+
+wiringPi Copyright (c) 2012 Gordon Henderson
+https://projects.drogon.net/raspberry-pi/wiringpi
+wiringPi is free software: GNU Lesser General Public License
+see <http://www.gnu.org/licenses/>
+*/
+
+#include <stdio.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <string.h>
+#include <sys/wait.h>
+#include <sys/ioctl.h>
+#include <poll.h>
+#include <sys/stat.h>
+#include "interrupt.h"
+#include <pthread.h>
+
+//#define delay(x) bcm2835_delay(x)
+
+static pthread_mutex_t pinMutex = PTHREAD_MUTEX_INITIALIZER ;
+static volatile int    pinPass = -1 ;
+
+pthread_t threadId [64];
+
+// sysFds:
+//      Map a file descriptor from the /sys/class/gpio/gpioX/value
+static int sysFds [64] =
+{
+  -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+  -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+  -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+  -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+} ;
+
+// ISR Data
+static void (*isrFunctions [64])(void) ;
+
+int waitForInterrupt (int pin, int mS)
+{
+  int fd, x ;
+  uint8_t c ;
+  struct pollfd polls ;
+
+  if ((fd = sysFds [pin]) == -1)
+    return -2 ;
+
+// Setup poll structure
+
+  polls.fd     = fd ;
+  polls.events = POLLPRI ;      // Urgent data!
+
+// Wait for it ...
+  x = poll (&polls, 1, mS) ;
+
+// Do a dummy read to clear the interrupt
+//      A one character read appars to be enough.
+//      Followed by a seek to reset it.
+
+  (void)read (fd, &c, 1) ;
+  lseek (fd, 0, SEEK_SET) ;
+
+  return x ;
+}
+
+
+int piHiPri (const int pri)
+{
+  struct sched_param sched ;
+
+  memset (&sched, 0, sizeof(sched)) ;
+
+  if (pri > sched_get_priority_max (SCHED_RR))
+    sched.sched_priority = sched_get_priority_max (SCHED_RR) ;
+  else
+    sched.sched_priority = pri ;
+
+  return sched_setscheduler (0, SCHED_RR, &sched) ;
+}
+
+
+void *interruptHandler (void *arg)
+{
+  int myPin ;
+
+  (void)piHiPri (55) ;  // Only effective if we run as root
+
+  myPin   = pinPass ;
+  pinPass = -1 ;
+
+  for (;;)
+    if (waitForInterrupt (myPin, -1) > 0){
+      pthread_mutex_lock (&pinMutex) ;
+      isrFunctions [myPin] () ;
+      pthread_mutex_unlock (&pinMutex) ;
+	  pthread_testcancel(); //Cancel at this point if we have an cancellation request.
+    }
+
+  return NULL ;
+}
+
+
+int attachInterrupt (int pin, int mode, void (*function)(void))
+{
+  const char *modeS ;
+  char fName   [64] ;
+  char  pinS [8] ;
+  pid_t pid ;
+  int   count, i ;
+  char  c ;
+  int   bcmGpioPin ;
+
+  bcmGpioPin = pin ;
+
+  if (mode != INT_EDGE_SETUP)
+  {
+    /**/ if (mode == INT_EDGE_FALLING)
+      modeS = "falling" ;
+    else if (mode == INT_EDGE_RISING)
+      modeS = "rising" ;
+    else
+      modeS = "both" ;
+
+    sprintf (pinS, "%d", bcmGpioPin) ;
+
+    if ((pid = fork ()) < 0)    // Fail
+      return printf("wiringPiISR: fork failed: %s\n", strerror (errno)) ;
+
+    if (pid == 0)       // Child, exec
+    {
+      /**/ if (access ("/usr/local/bin/gpio", X_OK) == 0)
+      {
+        execl ("/usr/local/bin/gpio", "gpio", "edge", pinS, modeS, (char *)NULL) ;
+        return printf ("wiringPiISR: execl failed: %s\n", strerror (errno)) ;
+      }
+      else if (access ("/usr/bin/gpio", X_OK) == 0)
+      {
+        execl ("/usr/bin/gpio", "gpio", "edge", pinS, modeS, (char *)NULL) ;
+        return printf ("wiringPiISR: execl failed: %s\n", strerror (errno)) ;
+      }
+      else
+        return printf ("wiringPiISR: Can't find gpio program\n") ;
+    }
+    else                // Parent, wait
+      wait (NULL) ;
+  }
+
+  if (sysFds [bcmGpioPin] == -1)
+  {
+    sprintf (fName, "/sys/class/gpio/gpio%d/value",bcmGpioPin);
+    if ((sysFds [bcmGpioPin] = open (fName, O_RDWR)) < 0)
+      return printf ("wiringPiISR: unable to open %s: %s\n", fName, strerror (errno)) ;
+  }
+
+    ioctl (sysFds [bcmGpioPin], FIONREAD, &count) ;
+  for (i = 0 ; i < count ; ++i)
+    read (sysFds [bcmGpioPin], &c, 1) ;
+
+  isrFunctions [pin] = function ;
+
+  pthread_mutex_lock (&pinMutex) ;
+    pinPass = pin ;
+    pthread_create (&threadId[bcmGpioPin], NULL, interruptHandler, NULL) ;
+    while (pinPass != -1)
+      delay (1) ;
+  pthread_mutex_unlock (&pinMutex) ;
+
+  return 0 ;
+}
+
+int detachInterrupt (int pin)
+{
+	char  pinS [8];
+    const char *modeS = "none";
+	pid_t pid ;
+	
+	if (!pthread_cancel(threadId[pin])) //Cancel the thread
+	{
+	 return 0;
+	}
+	
+	if (!close(sysFds[pin])) //Close filehandle
+	{
+		return 0;
+	}
+	
+	/* Set wiringPi to 'none' interrupt mode */
+
+    sprintf (pinS, "%d", pin) ;
+
+    if ((pid = fork ()) < 0)    // Fail
+      return printf("wiringPiISR: fork failed: %s\n", strerror (errno)) ;
+
+    if (pid == 0)       // Child, exec
+    {
+      /**/ if (access ("/usr/local/bin/gpio", X_OK) == 0)
+      {
+        execl ("/usr/local/bin/gpio", "gpio", "edge", pinS, modeS, (char *)NULL) ;
+        return printf ("wiringPiISR: execl failed: %s\n", strerror (errno)) ;
+      }
+      else if (access ("/usr/bin/gpio", X_OK) == 0)
+      {
+        execl ("/usr/bin/gpio", "gpio", "edge", pinS, modeS, (char *)NULL) ;
+        return printf ("wiringPiISR: execl failed: %s\n", strerror (errno)) ;
+      }
+      else
+        return printf ("wiringPiISR: Can't find gpio program\n") ;
+    }
+    else                // Parent, wait
+      wait (NULL) ;
+	  
+	return 1;
+}
+
+void rfNoInterrupts(){
+  pthread_mutex_lock (&pinMutex) ;
+}
+
+void rfInterrupts(){
+  pthread_mutex_unlock (&pinMutex) ;
+}
\ No newline at end of file

utility/BBB/interrupt.h

+/*
+Interrupts functions extruded from wiringPi library by Oitzu.
+
+wiringPi Copyright (c) 2012 Gordon Henderson
+https://projects.drogon.net/raspberry-pi/wiringpi
+wiringPi is free software: GNU Lesser General Public License
+see <http://www.gnu.org/licenses/>
+*/
+
+#include "RF24_arch_config.h"
+
+#define INT_EDGE_SETUP          0
+#define INT_EDGE_FALLING        1
+#define INT_EDGE_RISING         2
+#define INT_EDGE_BOTH           3
+
+/*
+ * interruptHandler:
+ *      This is a thread and gets started to wait for the interrupt we're
+ *      hoping to catch. It will call the user-function when the interrupt
+ *      fires.
+ *********************************************************************************
+ */
+void *interruptHandler (void *arg);
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+/*
+ * waitForInterrupt:
+ *      Pi Specific.
+ *      Wait for Interrupt on a GPIO pin.
+ *      This is actually done via the /sys/class/gpio interface regardless of
+ *      the wiringPi access mode in-use. Maybe sometime it might get a better
+ *      way for a bit more efficiency.
+ *********************************************************************************
+ */
+extern int waitForInterrupt (int pin, int mS);
+
+/*
+ * piHiPri:
+ *      Attempt to set a high priority schedulling for the running program
+ *********************************************************************************
+ */
+extern int piHiPri (const int pri);
+
+/*
+ * attachInterrupt (Original: wiringPiISR):
+ *      Pi Specific.
+ *      Take the details and create an interrupt handler that will do a call-
+ *      back to the user supplied function.
+ *********************************************************************************
+ */
+extern int attachInterrupt (int pin, int mode, void (*function)(void));
+
+/*
+ * detachInterrupt:
+ *      Pi Specific detachInterrupt.
+ *      Will cancel the interrupt thread, close the filehandle and 
+ *		setting wiringPi back to 'none' mode.
+ *********************************************************************************
+ */
+extern int detachInterrupt (int pin);
+
+extern void rfNoInterrupts();
+extern void rfInterrupts();
+#ifdef __cplusplus
+}
+#endif
\ No newline at end of file

utility/BBB/spi.cpp

@@ -48,12 +48,9 @@ void SPI::init()
 {
 	int ret;
     
-    if(this->fd > 0) {
-        close(this->fd);
-    }
-    
-	this->fd = open(this->device.c_str(), O_RDWR);
-	
+    if( !(this->fd > 0)){
+	  this->fd = open(this->device.c_str(), O_RDWR);
+	}
     if (this->fd < 0)
 	{
 		perror("can't open device");
@@ -124,10 +121,10 @@ uint8_t SPI::transfer(uint8_t tx_)
 	tr.len = 1,//ARRAY_SIZE(tx),
 	tr.delay_usecs = 0,
 	tr.cs_change=1,
-	tr.speed_hz = this->speed,
 	tr.bits_per_word = this->bits,
 	};
 	
+    tr.speed_hz = this->speed,	
 	//Note: On RPi, for some reason I started getting 'bad message' errors, and changing the struct as below fixed it, until an update...??
 	//
 	/*	// One byte is transfered at once
@@ -165,9 +162,9 @@ void SPI::transfernb(char* tbuf, char* rbuf, uint32_t len)
 		tr.len = len,//ARRAY_SIZE(tx),
 		tr.cs_change=1,
 		tr.delay_usecs = 0,
-		tr.speed_hz = this->speed,
 		tr.bits_per_word = this->bits,
 	};
+        tr.speed_hz = this->speed,    
 	
 	//Note: On RPi, for some reason I started getting 'bad message' errors, and changing the struct as below fixed it, until an update...??
 	// One byte is transfered at once