Merge pull request #152 from zsserg/master

Error handling for setting up pinmux mode in gpio.setup()

Author: pdp7

source/c_pinmux.c

@@ -1,5 +1,6 @@
 #include <stdio.h>
 #include <string.h>
+#include <syslog.h>
 
 #include "c_pinmux.h"
 #include "common.h"
@@ -34,10 +35,10 @@ BBIO_err set_pin_mode(const char *key, const char *mode)
 	f = fopen(path, "w");
 	if (NULL == f) {
 		return BBIO_ACCESS;
-	} 
-
+	}
+	syslog(LOG_DEBUG, "set_pin_mode() :: Pinmux file %s access OK", path); 
 	fprintf(f, "%s", mode);
 	fclose(f);
-
+	syslog(LOG_DEBUG, "set_pin_mode() :: Set pinmux mode to %s for %s", mode, pin);
 	return BBIO_OK;
 }

source/py_gpio.c

@@ -138,12 +138,18 @@ static PyObject *py_setup_channel(__attribute__ ((unused)) PyObject *self, PyObj
        }
 
    } else {
-	   if (pud == PUD_DOWN)
-		   set_pin_mode(channel, "gpio_pd");
+       if (pud == PUD_DOWN)
+		   res = set_pin_mode(channel, "gpio_pd");
 	   else if (pud == PUD_UP)
-		   set_pin_mode(channel, "gpio_pu");
+		   res = set_pin_mode(channel, "gpio_pu");
 	   else
-		   set_pin_mode(channel, "gpio");
+		   res = set_pin_mode(channel, "gpio");
+   }
+   
+   //Check if set_pin_mode() returned no error
+   if (res != BBIO_OK) {
+       PyErr_SetString(PyExc_ValueError, "Set gpio mode failed, missing file or invalid permissions.");
+       return NULL;
    }
 
    gpio_direction[gpio] = direction;