Adding a device driver to the linux kernel for android opens up a whole pandora’s box of issues that are related to building the driver and then integrating it into the whole android infrastructure.
I have always tried to take the shortcut approach of getting a build from one of the board manufacturers, and then using it as it is and make the minimal modifications that I need.
Some of the tips I have found along the way…
Sending a keystroke over ADB
A lot of times the screen will turn off on the dev board I am using and I cannot see what is on the screen. Some cool ways to turn on the screen are at…
If you dont want to read through a link, here is the quick summary…
adb shell input keyevent KEYCODE_POWER
Somtimes KEYCODE_MENU is better because it will also unlock the screen.
This helps a lot when you have a headless board and dont have a mouse handy to wake up the board. But it brings up to the next issue, how do I unlock the screen.
http://stackoverflow.com/questions/29072501/how-to-unlock-android-phone-through-adb
and again, the quick summary…
adb shell input keyevent 26 #Pressing the lock button adb shell input touchscreen swipe 930 880 930 380 #Swipe UP
This one assumes that you only have a swipe turned on as it is by default in most android builds. If you are crazy enough to set a passcode…read the link.
If you want to tap somewhere on the screen…
adb shell input tap 500 1450
If you want more info on the types of events…
http://stackoverflow.com/questions/7789826/adb-shell-input-events
In case you want more information on the types of input events…
https://developer.android.com/guide/topics/ui/ui-events.html
Samyeer Metrani 