Talk:Backlight control

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Force display rotate -- 02:36, 5 October 2011 (MDT)

Hi, is there any way (without rebuilding Android image) to force a screen rotate in your Android Gingerbread. I still need landscape but rotated by 180. Some setprop, or something at kernel level? Regards, Miroslav

Re: Force display rotate -- Npavel 11:44, 6 October 2011 (MDT)

You can try: ro.sf.hwrotate 180 but I haven't tested if it works without hardware support (which atmelfb doesn't have).If that doesn't work your best bet is to generate a dummy sensor signal to let android do it's rendering rotated.See here:

Also on frameworks/base/services/surfaceflinger/SurfaceFlinger.cpp in function: void GraphicPlane::setDisplayHardware(DisplayHardware *hw) you need a add a case for 180 (ISurfaceComposer::eOrientation180)

Re: Force display rotate -- 07:48, 14 October 2011 (MDT)

Yes, it seems like setprop does not work, cause it does not have real graphics IP, just simple FB. Will try these as suggested in SurfaceFlinger.

touch calibration -- 10:11, 5 October 2011 (MDT)

Hi, what can we do about calibration of the touch controller. Is there a way to do it manually, or some software/firmware for this operation? Regards, Miroslav Any info on this issue?

Re: touch calibration -- Npavel 11:47, 6 October 2011 (MDT)

Android Eclair version has the calibration app. For gingerbread we haven't tried to add calibration since we will have a capacitive touchscreen option.

You might try to hack the kernel driver (might be easier then android) if you find out a pattern needed to calibrate your touch panel (eg: X is always +30px off, Y is always -50px off)

Re: touch calibration -- 07:45, 14 October 2011 (MDT)

OK, Thank you, will try this right away! But, I think the pattern is not so simple, in the middle the touch is OK, but near the edges it is not good. And, how would we do this in kernel, could you please, be more specific to point the files needed to tweak. Just one point, if there is going to be a capacitive touch it will still need some calibration(usually it is a firmware inside the touch), am I right? Also, it would be nice to point where in Eclair to find the calibration, so we would try and patch the Gingerbread version (been doing Gingerbread patching from Froyo patches for one major MCU company for a year now).

Re: Re: touch calibration -- Npavel 09:25, 16 October 2011 (MDT)

Yes you are right, the capacitive touchscreen will be factory calibrated in the firmware for our enclosure/lcd.

For calibration in eclair see: For the kernel look at drivers/input/touchscreen/atmel_tsadcc.c there are some hacks already there (for a resistive touchscreen with buttons on bottom)

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