The evdev interface will report a resolution in absinfo, indicating the unit of value. It's currently not used in ozone, so the radius_x and radius_y will be wrong when chrome run on device reporting resolution.


Kernel definition of input_absinfo is here:
/**
 * struct input_absinfo - used by EVIOCGABS/EVIOCSABS ioctls
 * @value: latest reported value for the axis.
 * @minimum: specifies minimum value for the axis.
 * @maximum: specifies maximum value for the axis.
 * @fuzz: specifies fuzz value that is used to filter noise from
 *	the event stream.
 * @flat: values that are within this value will be discarded by
 *	joydev interface and reported as 0 instead.
 * @resolution: specifies resolution for the values reported for
 *	the axis.
 *
 * Note that input core does not clamp reported values to the
 * [minimum, maximum] limits, such task is left to userspace.
 *
 * Resolution for main axes (ABS_X, ABS_Y, ABS_Z) is reported in
 * units per millimeter (units/mm), resolution for rotational axes
 * (ABS_RX, ABS_RY, ABS_RZ) is reported in units per radian.
 */
struct input_absinfo {
	__s32 value;
	__s32 minimum;
	__s32 maximum;
	__s32 fuzz;
	__s32 flat;
	__s32 resolution;
};