Input: document struct input_absinfo

Add documentation for struct input_absinfo that is used in EVIOCGABS
and EVIOCSABS ioctl and specify units of measure used for reporting
resolution for an axis.

Acked-by: Henrik Rydberg <rydberg@euromail.se>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
This commit is contained in:
Dmitry Torokhov 2010-11-29 23:33:04 -08:00
parent 0417596f66
commit 86b17f76f4
1 changed files with 20 additions and 1 deletions

View File

@ -47,6 +47,25 @@ struct input_id {
__u16 version;
};
/**
* 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;
@ -1134,7 +1153,7 @@ struct input_mt_slot {
* of tracked contacts
* @mtsize: number of MT slots the device uses
* @slot: MT slot currently being transmitted
* @absinfo: array of &struct absinfo elements holding information
* @absinfo: array of &struct input_absinfo elements holding information
* about absolute axes (current value, min, max, flat, fuzz,
* resolution)
* @key: reflects current state of device's keys/buttons