Differences

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--- en:acc:vu8 [2017/01/19 12:02]
joy.cho [3. Backlight control with PWM.]
+++ en:acc:vu8 [2017/05/22 09:09] (current)
odroid [ODROID-VU8C]
@@ Line 6: / Line 6: @@
 [[http://www.hardkernel.com/main/products/prdt_info.php?g_code=G147918565945|Where to buy]]
+Assembly guide by ETA PRIME !
+{{youtube>0eSQ7iG_PlY?medium}}
 ====== Specifications ======
   * 8-inch TFT-LCD
@@ Line 64: / Line 67: @@
 <code>
 path="/sys/class/gpio"
-echo 234 > $path/export
 echo 214 > $path/export
-echo out > $path/gpio234/direction
 echo out > $path/gpio214/direction
-echo 0 > $path/gpio234/value
 echo 0 > $path/gpio214/value
 </code>
@@ Line 75: / Line 75: @@
 path="/sys/class/gpio"
 echo 97 > $path/export
-echo 108 > $path/export
 echo out > $path/gpio97/direction
-echo out > $path/gpio108/direction
 echo 0 > $path/gpio97/value
-echo 0 > $path/gpio108/value
 </code>
@@ Line 90: / Line 87: @@
 </code>
-Add "vu8c backlight control" part in "/init.odroid.board.rc" as following.
+Make or download the following shell script of the board model that you're using (C1 or C2)\\
+and copy it in **/system/bin/**.\\
+And make its permission executable.
-**ODROID-C2**
 <code>
-....
+# su
-.....
+# chmod 755 /system/bin/vu8c_backlight_c2_android.sh
-on boot
+</code>
-    setprop ro.radio.noril true
-    write /sys/class/freq_limit/limit 0
-    write /sys/devices/system/cpu/cpu0/cpufreq/scaling_dflt_freq 1536000
-# Permissions for bluetooth$
+**ODROID-C2**
-    setprop ro.bt.bdaddr_path "/efs/bluetooth/bt_addr"$
+<file sh vu8c_backlight_c2_android.sh>
-    chown bluetooth bluetooth ro.bt.bdaddr_path$
+#!/bin/sh
-# vu8c backlight control
+path="/sys/class/gpio"
-    echo 234 > /sys/class/gpio/export
-    echo 214 > /sys/class/gpio/export
+echo 214 > $path/export
-    echo out > /sys/class/gpio/gpio234/direction
-    echo out > /sys/class/gpio/gpio214/direction
+echo out > $path/gpio214/direction
-    echo 0 > /sys/class/gpio/gpio234/value
+echo 0 > $path/gpio214/value
-    echo 0 > /sys/class/gpio/gpio214/value
+chown system system $path/gpio214/value
+</file>
+Now, you need to register the service to run this script automatically on boot time.\\
+Add the following lines in the end of /init.odroid.board.rc.\\
+Don't forget the root filesystem should be writable as aforementioned.
+<code>
+# su
+# vi /init.odroid.board.rc
 .....
 .....
+service vu8c_backlight /system/bin/vu8c_backlight_c2_android.sh
+    class main
+    user root
+    group root
+    oneshot
 </code>
 Then, reboot.
 <code>
 $ reboot
 </code>
-After reboot, you can confirm if the nodes are configured normally by checking "gpio214" and "gpio234".
+After reboot, you can confirm if the nodes are configured normally by checking "gpio214".
 <code>
 $ ls /sys/class/gpio/
 export
 gpio214
-gpio234
 gpiochip122
 gpiochip136
@@ Line 130: / Line 139: @@
 </code>
+**ODROID-C1**
+<file sh vu8c_backlight_c1_android.sh>
+#!/bin/sh
+path="/sys/class/gpio"
+echo 97 > $path/export
+echo out > $path/gpio97/direction
+echo 0 > $path/gpio97/value
+chown system system $path/gpio97/value
+</file>
+Now, you need to register the service to run this script automatically on boot time.\\
+Add the following lines in the end of /init.odroid.board.rc.\\
+Don't forget the root filesystem should be writable as aforementioned.
-**ODROID-C1**
 <code>
+# su
+# vi /init.odroid.board.rc
 .....
 .....
-on boot
+service vu8c_backlight /system/bin/vu8c_backlight_c2_android.sh
-    write /sys/class/freq_limit/limit 0
+    class main
-.....
+    user root
-.....
+    group root
-#add for mali scaling mode set
+    oneshot
-    chown system /sys/module/mali/parameters/scaling_mode
-# vu8c backlight control
-    echo 97 > /sys/class/gpio/export
-    echo 108 > /sys/class/gpio/export
-    echo out > /sys/class/gpio/gpio97/direction
-    echo out > /sys/class/gpio/gpio108/direction
-    echo 0 > /sys/class/gpio/gpio97/value
-    echo 0 > /sys/class/gpio/gpio108/value
-.....
-.....
 </code>
 Then, reboot.
@@ Line 157: / Line 171: @@
 $ reboot
 </code>
-After reboot, you can confirm if the nodes are configured normally by checking "gpio97" and "gpio108".
+After reboot, you can confirm if the nodes are configured normally by checking "gpio97".
 <code>
 $ ls /sys/class/gpio/
 export
 gpio97
-gpio108
 ......
 ......
@@ Line 201: / Line 214: @@
 echo 1 | sudo tee /sys/devices/platform/pwm-ctrl/enable0
 </code>
-Set duty ratio (value can be 0 to 1023. Higher is brighter)
+Set duty ratio (value can be 0 to 1023. Lower is brighter)
 <code>
 echo 1023 | sudo tee /sys/devices/platform/pwm-ctrl/duty0
@@ Line 216: / Line 229: @@
 <code>
-root@odroidc2:/ # cd /sys/devices/pwm-ctrl.46/
+root@odroidc2:/ # cd /sys/devices/pwm-ctrl.43/
-root@odroidc2:/sys/devices/pwm-ctrl.46 # ls
+root@odroidc2:/sys/devices/pwm-ctrl.43 # ls
 driver
 duty0
@@ Line 226: / Line 239: @@
 subsystem
 uevent
-root@odroidc2:/sys/devices/pwm-ctrl.46 # cat enable0
+root@odroidc2:/sys/devices/pwm-ctrl.43 # cat enable0
 PWM_0 : off
-root@odroidc2:/sys/devices/pwm-ctrl.46 # echo 1 > enable0
+root@odroidc2:/sys/devices/pwm-ctrl.43 # echo 1 > enable0
-root@odroidc2:/sys/devices/pwm-ctrl.46 # cat enable0
+root@odroidc2:/sys/devices/pwm-ctrl.43 # cat enable0
 PWM_0 : on
+</code>
+Set default frequency.
+<code>
+root@odroidc2:/sys/devices/pwm-ctrl.43 # echo 100000 > freq0
 </code>
 Set duty ratio.\\
-Value can be 0 to 1023 and higher value means brighter.
+Value can be 0 to 1023 and lower value means brighter.
 <code>
-root@odroidc2:/sys/devices/pwm-ctrl.46 # cat duty0
+root@odroidc2:/sys/devices/pwm-ctrl.43 # cat duty0
-root@odroidc2:/sys/devices/pwm-ctrl.46 #echo 160 > duty0
+root@odroidc2:/sys/devices/pwm-ctrl.43 #echo 160 > duty0
-root@odroidc2:/sys/devices/pwm-ctrl.46 # cat duty0
+root@odroidc2:/sys/devices/pwm-ctrl.43 # cat duty0
 </code>