Function drmtap_cursor_hotspot_valid 

pub unsafe extern "C" fn drmtap_cursor_hotspot_valid(
    cursor: *const drmtap_cursor_info,
    valid: *mut c_int,
) -> c_int

Whether the cursor’s hotspot came from the driver’s HOTSPOT_X/HOTSPOT_Y plane properties rather than from their absence. 0 on success with valid set, -EINVAL on a null argument, -ENOTSUP when the sample carries no such answer (a cursor read through an older privileged helper). Added in 0.5.6.