added in GPIO led functionality

scripts/gpio

@@ -0,0 +1,55 @@
+#!/bin/bash
+
+# Utility to control the GPIO pins of the Raspberry Pi
+# Can be called as a script or sourced so that the gpio
+# function can be called directly
+
+function gpio()
+{
+    local verb=$1
+    local pin=$2
+    local value=$3
+
+    local pins=($GPIO_PINS)
+    if [[ "$pin" -lt ${#pins[@]} ]]; then
+        local pin=${pins[$pin]}
+    fi
+
+    local gpio_path=/sys/class/gpio
+    local pin_path=$gpio_path/gpio$pin
+
+    case $verb in
+        read)
+            cat $pin_path/value
+        ;;
+
+        write)
+            sudo sh -c "echo $value > $pin_path/value"
+        ;;
+
+        mode)
+            if [ ! -e $pin_path ]; then
+               sudo sh -c "echo $pin > $gpio_path/export"
+            fi
+            sudo sh -c "echo $value > $pin_path/direction"
+        ;;
+
+        state)
+            if [ -e $pin_path ]; then
+                local dir=$(cat $pin_path/direction)
+                local val=$(cat $pin_path/value)
+                echo "$dir $val"
+            fi
+        ;;
+        clean)
+            sudo sh -c "echo 0 > $pin_path/value"
+            sudo sh -c "echo $pin > $gpio_path/unexport"
+        ;;
+
+    esac
+}
+
+# Just invoke our function if the script is called directly
+if [ "$BASH_SOURCE" == "$0" ]; then
+    gpio $@
+fi