gpio: Added args param to maa_gpio_isr and added documentation

Signed-off-by: Kiveisha Yevgeniy <yevgeniy.kiveisha@intel.com>

api/maa/gpio.h

@@ -115,9 +115,10 @@ maa_result_t maa_gpio_edge_mode(maa_gpio_context dev, gpio_edge_t mode);
  * @param edge The edge mode to set the gpio into
  * @param fptr Function pointer to function to be called when interupt is
  * triggered
+ * @param args Arguments passed to the interrupt handler (fptr)
  * @return Result of operation
  */
-maa_result_t maa_gpio_isr(maa_gpio_context dev, gpio_edge_t edge, void (*fptr)(void));
+maa_result_t maa_gpio_isr(maa_gpio_context dev, gpio_edge_t edge, void (*fptr)(void *), void * args);
 
 /**
  * Stop the current interupt watcher on this Gpio, and set the Gpio edge mode

api/maa/gpio.hpp

@@ -104,17 +104,21 @@ class Gpio {
             return maa_gpio_edge_mode(m_gpio, (gpio_edge_t) mode);
         }
 #if defined(SWIGPYTHON)
-        maa_result_t isr(Edge mode, PyObject *pyfunc) {
-            return maa_gpio_isr(m_gpio, (gpio_edge_t) mode, (void (*) ()) pyfunc);
+        maa_result_t isr(Edge mode, PyObject *pyfunc, PyObject* args) {
+            return maa_gpio_isr(m_gpio, (gpio_edge_t) mode, (void (*) (void *)) pyfunc, (void *) args);
         }
 #else
         /**
          * Sets a callback to be called when pin value changes
          *
+         * @param mode The edge mode to set
+         * @param fptr Function pointer to function to be called when interupt is
+         * triggered
+         * @param args Arguments passed to the interrupt handler (fptr)
          * @return Result of operation
          */
-        maa_result_t isr(Edge mode, void (*fptr)(void)) {
-            return maa_gpio_isr(m_gpio, (gpio_edge_t) mode, fptr);
+        maa_result_t isr(Edge mode, void (*fptr)(void *), void * args) {
+            return maa_gpio_isr(m_gpio, (gpio_edge_t) mode, fptr, args);
         }
 #endif
         /**

examples/isr_pin6.c

@@ -29,7 +29,7 @@
 static volatile int counter = 0;
 static volatile int oldcounter = 0;
 
-void interrupt (void) {
+void interrupt (void * args) {
     ++counter;
 }
 
@@ -47,7 +47,7 @@ int main ()
 
     gpio_edge_t edge = MAA_GPIO_EDGE_BOTH;
    
-    maa_gpio_isr(x, edge, &interrupt);
+    maa_gpio_isr(x, edge, &interrupt, NULL);
 
     for(;;) {
         if(counter != oldcounter) {

examples/python/hello_isr.py

@@ -2,9 +2,9 @@
 
 import pymaa as maa
 
-def test():
+def test(args):
   print("wooo")
 
 x = maa.Gpio(6)
 x.dir(maa.DIR_IN)
-x.isr(maa.EDGE_BOTH, test)
+x.isr(maa.EDGE_BOTH, test, test)

src/gpio/gpio.c

@@ -48,7 +48,8 @@ struct _gpio {
     int pin; /**< the pin number, as known to the os. */
     int phy_pin; /**< pin passed to clean init. -1 none and raw*/
     int value_fp; /**< the file pointer to the value of the gpio */
-    void (* isr)(); /**< the interupt service request */
+    void (* isr)(void *); /**< the interupt service request */
+    void *isr_args; /**< args return when interupt service request triggered */
     pthread_t thread_id; /**< the isr handler thread id */
     int isr_value_fp; /**< the isr file pointer on the value */
     maa_boolean_t owner; /**< If this context originally exported the pin */
@@ -183,12 +184,24 @@ maa_gpio_interrupt_handler(void* arg)
             // nessecary but especially if doing IO (like print()) python will segfault
             // if we do not hold a lock on the GIL
             PyGILState_STATE gilstate = PyGILState_Ensure();
-
-            PyEval_CallObject((PyObject*)dev->isr, NULL);
+            PyObject *arglist;
+            PyObject *ret;
+            arglist = Py_BuildValue("(i)", dev->isr_args);
+			if (arglist == NULL) {
+				fprintf(stdout, "Py_BuildValue NULL\n");
+			} else {
+                ret = PyEval_CallObject((PyObject*)dev->isr, arglist);
+                if (ret == NULL) {
+                    fprintf(stdout, "PyEval_CallObject failed\n");
+                } else {
+                    Py_DECREF(ret);
+                }
+                Py_DECREF(arglist);
+            }
 
             PyGILState_Release (gilstate);
 #else
-            dev->isr();
+            dev->isr(dev->isr_args);
 #endif
             pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, NULL);
         } else {
@@ -196,7 +209,7 @@ maa_gpio_interrupt_handler(void* arg)
             pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, NULL);
             close(dev->isr_value_fp);
             dev->isr_value_fp = -1;
-        return NULL;
+            return NULL;
         }
     }
 }
@@ -248,15 +261,19 @@ maa_gpio_edge_mode(maa_gpio_context dev, gpio_edge_t mode)
 }
 
 maa_result_t
-maa_gpio_isr(maa_gpio_context dev, gpio_edge_t mode, void (*fptr)(void))
+maa_gpio_isr(maa_gpio_context dev, gpio_edge_t mode, void (*fptr)(void *), void * args)
 {
     // we only allow one isr per maa_gpio_context
     if (dev->thread_id != 0) {
         return MAA_ERROR_NO_RESOURCES;
     }
 
-    maa_gpio_edge_mode(dev, mode);
+    if (MAA_SUCCESS != maa_gpio_edge_mode(dev, mode)) {
+        return MAA_ERROR_UNSPECIFIED;
+    }
+        
     dev->isr = fptr;
+    dev->isr_args = args;
     pthread_create (&dev->thread_id, NULL, maa_gpio_interrupt_handler, (void *) dev);
 
     return MAA_SUCCESS;