Allow no root to use gpio for raspberry pi

Author: nicolas-rabault

Adafruit_DHT/Raspberry_Pi.py

@@ -31,7 +31,7 @@ def read(sensor, pin):
 		# Signal no result could be obtained, but the caller can retry.
 		return (None, None)
 	elif result == common.DHT_ERROR_GPIO:
-		raise RuntimeError('Error accessing GPIO. Make sure program is run as root with sudo!')
+		raise RuntimeError('Error accessing GPIO.')
 	elif result != common.DHT_SUCCESS:
 		# Some kind of error occured.
 		raise RuntimeError('Error calling DHT test driver read: {0}'.format(result))

source/Raspberry_Pi/pi_mmio.c

@@ -37,9 +37,9 @@ volatile uint32_t* pi_mmio_gpio = NULL;
 
 int pi_mmio_init(void) {
   if (pi_mmio_gpio == NULL) {
-    int fd = open("/dev/mem", O_RDWR | O_SYNC);
+    int fd = open("/dev/gpiomem", O_RDWR | O_SYNC);
     if (fd == -1) {
-      // Error opening /dev/mem.  Probably not running as root.
+      // Error opening /dev/gpiomem.
       return MMIO_ERROR_DEVMEM;
     }
     // Map GPIO memory to location in process space.