> I know Android use the touchscreen like an input device but I don't > know what are the values it wants? (X,Y,...) What is the unit? (pixel, > mm...)
It will be (x,y) co-ordinates, where (0,0) being the top-left of the screen and (max-x, max-y) being the bottom of the screen. how it works: - when user taps touch screen, it generates an interrupt and its the trigger for touch screen driver to read the (x,y) co-ordinate from touch-screen controller. touch screen controller returns samples that its h/w calculated. (can be resistive/capacitive). Once, x,y coordinates are ready, driver publishes using input_report_abs calls. its still a black box for me, how OS takes (x,y) from this user event, maps to a framebuffer locaiton, and do some stuff.. u can refer a sample touch screen driver at http://git.omapzoom.org/?p=kernel/omap.git;a=blob;f=drivers/input/touchscreen/tsc2007.c >> Do you know which part of Android read the event file (dev/input/event) of >> the touchscreen? EventHub.., "Grand Central Station for events" - as called by android team ;P ./frameworks/base/libs/ui/EventHub.cpp Link - http://git.omapzoom.org/?p=platform/frameworks/base.git;a=blob;f=libs/ui/EventHub.cpp On Wed, Apr 7, 2010 at 12:45 PM, Arnaud Frigout <[email protected]> wrote: > Hello All: > > I'm porting Android on an imx51 for a new touchscreen. > I know Android use the touchscreen like an input device but I don't > know what are the values it wants? (X,Y,...) What is the unit? (pixel, > mm...) > Do you know which part of Android read the event file (dev/input/ > event) of the touchscreen? > Where can I find a documentattion on this item? > > > Best regards, > > Arnaud Frigout > > -- > unsubscribe: [email protected] > website: http://groups.google.com/group/android-porting > > To unsubscribe, reply using "remove me" as the subject. > -- unsubscribe: [email protected] website: http://groups.google.com/group/android-porting
