• Jason Gerecke's avatar
    HID: wacom: Add angular resolution data to some ABS axes · 26fe4124
    Jason Gerecke authored
    Provide the resolution of several angular axes (tilt, pen rotation, puck
    rotation) to userspace. Because these values are natively degree-based, we
    need to convert them to into units/radian as required by the input_absinfo
    struct. To ensure wraparound behaves properly for the rotation axes, the
    converted value was rounded up rather than rounded nearest.
    
    Notably, the touchring axes (ABS_WHEEL and ABS_THROTTLE) are left without a
    a declared resolution because the their low resolution cannot be accurately
    represented (the worst-case rounding-induced error would be ~16 degrees).
    Pre-scaling the values and range by at least 10x would reduce the error in
    the resolution to acceptable levels, but the xf86-input-wacom driver is not
    able to use pre-scaled values for these axes at this time.
    Signed-off-by: default avatarJason Gerecke <killertofu@gmail.com>
    Reviewed-by: default avatarPing Cheng <pingc@wacom.com>
    Signed-off-by: default avatarJiri Kosina <jkosina@suse.cz>
    26fe4124
wacom_wac.c 98.8 KB