Let's look at this driver source: http://www.acs.com.hk/download-driver-unified/6258/ACS-Unified-Driver-Lnx-Mac-113-P.zipAfter compilation, we seems to end up with two files:libacsccid.so92-libacsccid1.rules(there is also Info.plist but it seems to be OS X specific)On make install first file is being put into /usr/lib/pcsc/drivers/ifd-acsccid.bundle/Contents/Linux/libacsccid.so, and second is supposed to be put in /etc/udev/rules.d/.The question is... how Linux knows that libacsccid.so file is a driver that has to be used in the specific situation?This is output of: make --dry-run install:fail=; \if (target_option=k; case ${target_option-} in ?) ;; *) echo am__make_running_with_option: internal error: invalid target option '${target_option-}' specified >&2; exit 1;; esac; has_opt=no; sane_makeflags=$MAKEFLAGS; if { if test -z '0'; then false; elif test -n 'x86_64-pc-linux-gnu'; then true; elif test -n '4.2.1' && test -n '/home/luken/Pobrane/acs-driver/ACS-Unified-Driver-Lnx-Mac-113-P/acsccid-1.1.3'; then true; else false; fi; }; then sane_makeflags=$MFLAGS; else case $MAKEFLAGS in *\\[\ \   ]*) bs=\\; sane_makeflags=`printf '%s\n' $MAKEFLAGS | sed s/$bs$bs[$bs $bs   ]*//g`;; esac; fi; skip_next=no; strip_trailopt () { flg=`printf '%s\n' $flg | sed s/$1.*$//`; }; for flg in $sane_makeflags; do test $skip_next = yes && { skip_next=no; continue; }; case $flg in *=*|--*) continue;; -*I) strip_trailopt 'I'; skip_next=yes;; -*I?*) strip_trailopt 'I';; -*O) strip_trailopt 'O'; skip_next=yes;; -*O?*) strip_trailopt 'O';; -*l) strip_trailopt 'l'; skip_next=yes;; -*l?*) strip_trailopt 'l';; -[dEDm]) skip_next=yes;; -[JT]) skip_next=yes;; esac; case $flg in *$target_option*) has_opt=yes; break;; esac; done; test $has_opt = yes); then \  failcom='fail=yes'; \else \  failcom='exit 1'; \fi; \dot_seen=no; \target=`echo install-recursive | sed s/-recursive//`; \case install-recursive in \  distclean-* | maintainer-clean-*) list='src' ;; \  *) list='src' ;; \esac; \for subdir in $list; do \  echo Making $target in $subdir; \  if test $subdir = .; then \    dot_seen=yes; \    local_target=$target-am; \  else \    local_target=$target; \  fi; \  (CDPATH=${ZSH_VERSION+.}: && cd $subdir && make  $local_target) \  || eval $failcom; \done; \if test $dot_seen = no; then \  make  $target-am || exit 1; \fi; test -z $failMaking install in srcmake[1]: Wejcie do katalogu '/home/luken/Pobrane/acs-driver/ACS-Unified-Driver-Lnx-Mac-113-P/acsccid-1.1.3/src'./create_Info_plist.pl ./supported_readers.txt ./Info.plist.src --target=libacsccid.so --version=1.1.3 --no-class > Info.plist/bin/sh /home/luken/Pobrane/acs-driver/ACS-Unified-Driver-Lnx-Mac-113-P/acsccid-1.1.3/config/install-sh -d /usr/lib/pcsc/drivers/ifd-acsccid.bundle/Contents/Linux/cp Info.plist /usr/lib/pcsc/drivers/ifd-acsccid.bundle/Contents/cp .libs/libacsccid.so /usr/lib/pcsc/drivers/ifd-acsccid.bundle/Contents/Linux/libacsccid.so/bin/echo -e \n\33[01;31m***************\n ; echo copy the src/92_pcscd_acsccid.rules file in udev directory (/etc/udev/rules.d/) ; /bin/echo -e \n***************\n\33[0mmake[1]: Opuszczenie katalogu '/home/luken/Pobrane/acs-driver/ACS-Unified-Driver-Lnx-Mac-113-P/acsccid-1.1.3/src'make[1]: Wejcie do katalogu '/home/luken/Pobrane/acs-driver/ACS-Unified-Driver-Lnx-Mac-113-P/acsccid-1.1.3'test -f config.h || rm -f stamp-h1test -f config.h || make  stamp-h1make  install-exec-am install-data-ammake[2]: Wejcie do katalogu '/home/luken/Pobrane/acs-driver/ACS-Unified-Driver-Lnx-Mac-113-P/acsccid-1.1.3'make[2]: Nie ma nic do zrobienia w 'install-exec-am'.make[2]: Nie ma nic do zrobienia w 'install-data-am'.make[2]: Opuszczenie katalogu '/home/luken/Pobrane/acs-driver/ACS-Unified-Driver-Lnx-Mac-113-P/acsccid-1.1.3'make[1]: Opuszczenie katalogu '/home/luken/Pobrane/acs-driver/ACS-Unified-Driver-Lnx-Mac-113-P/acsccid-1.1.3'And here is a content of 92-libacsccid1.rules:# udev rules for ACS CCID devices# If not adding the device, go awayACTION!=add, GOTO=pcscd_acsccid_rules_endSUBSYSTEM!=usb, GOTO=pcscd_acsccid_rules_endENV{DEVTYPE}!=usb_device, GOTO=pcscd_acsccid_rules_end# set USB power management to auto.ENV{ID_USB_INTERFACES}==:0b0000:, RUN+=/bin/sh -c 'echo auto > /sys/$devpath/power/control'# All doneLABEL=pcscd_acsccid_rules_endinstall-sh file:#!/bin/sh# install - install a program, script, or datafilescriptversion=2014-09-12.12; # UTC# This originates from X11R5 (mit/util/scripts/install.sh), which was# later released in X11R6 (xc/config/util/install.sh) with the# following copyright and license.## Copyright (C) 1994 X Consortium## Permission is hereby granted, free of charge, to any person obtaining a copy# of this software and associated documentation files (the Software), to# deal in the Software without restriction, including without limitation the# rights to use, copy, modify, merge, publish, distribute, sublicense, and/or# sell copies of the Software, and to permit persons to whom the Software is# furnished to do so, subject to the following conditions:## The above copyright notice and this permission notice shall be included in# all copies or substantial portions of the Software.## THE SOFTWARE IS PROVIDED AS IS, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE# X CONSORTIUM BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN# AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNEC-# TION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.## Except as contained in this notice, the name of the X Consortium shall not# be used in advertising or otherwise to promote the sale, use or other deal-# ings in this Software without prior written authorization from the X Consor-# tium.### FSF changes to this file are in the public domain.## Calling this script install-sh is preferred over install.sh, to prevent# 'make' implicit rules from creating a file called install from it# when there is no Makefile.## This script is compatible with the BSD install script, but was written# from scratch.tab='   'nl=''IFS= $tab$nl# Set DOITPROG to echo to test this script.doit=${DOITPROG-}doit_exec=${doit:-exec}# Put in absolute file names if you don't have them in your path;# or use environment vars.chgrpprog=${CHGRPPROG-chgrp}chmodprog=${CHMODPROG-chmod}chownprog=${CHOWNPROG-chown}cmpprog=${CMPPROG-cmp}cpprog=${CPPROG-cp}mkdirprog=${MKDIRPROG-mkdir}mvprog=${MVPROG-mv}rmprog=${RMPROG-rm}stripprog=${STRIPPROG-strip}posix_mkdir=# Desired mode of installed file.mode=0755chgrpcmd=chmodcmd=$chmodprogchowncmd=mvcmd=$mvprogrmcmd=$rmprog -fstripcmd=src=dst=dir_arg=dst_arg=copy_on_change=falseis_target_a_directory=possiblyusage=\Usage: $0 [OPTION]... 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DIRECTORY   or: $0 [OPTION]... -t DIRECTORY SRCFILES...   or: $0 [OPTION]... -d DIRECTORIES...In the 1st form, copy SRCFILE to DSTFILE.In the 2nd and 3rd, copy all SRCFILES to DIRECTORY.In the 4th, create DIRECTORIES.Options:     --help     display this help and exit.     --version  display version info and exit.  -c            (ignored)  -C            install only if different (preserve the last data modification time)  -d            create directories instead of installing files.  -g GROUP      $chgrpprog installed files to GROUP.  -m MODE       $chmodprog installed files to MODE.  -o USER       $chownprog installed files to USER.  -s            $stripprog installed files.  -t DIRECTORY  install into DIRECTORY.  -T            report an error if DSTFILE is a directory.Environment variables override the default commands:  CHGRPPROG CHMODPROG CHOWNPROG CMPPROG CPPROG MKDIRPROG MVPROG  RMPROG STRIPPROGwhile test $# -ne 0; do  case $1 in    -c) ;;    -C) copy_on_change=true;;    -d) dir_arg=true;;    -g) chgrpcmd=$chgrpprog $2        shift;;    --help) echo $usage; exit $?;;    -m) mode=$2        case $mode in          *' '* | *$tab* | *$nl* | *'*'* | *'?'* | *'['*)            echo $0: invalid mode: $mode >&2            exit 1;;        esac        shift;;    -o) chowncmd=$chownprog $2        shift;;    -s) stripcmd=$stripprog;;    -t)        is_target_a_directory=always        dst_arg=$2        # Protect names problematic for 'test' and other utilities.        case $dst_arg in          -* | [=\(\)!]) dst_arg=./$dst_arg;;        esac        shift;;    -T) is_target_a_directory=never;;    --version) echo $0 $scriptversion; exit $?;;    --) shift        break;;    -*) echo $0: invalid option: $1 >&2        exit 1;;    *)  break;;  esac  shiftdone# We allow the use of options -d and -T together, by making -d# take the precedence; this is for compatibility with GNU install.if test -n $dir_arg; then  if test -n $dst_arg; then    echo $0: target directory not allowed when installing a directory. >&2    exit 1  fifiif test $# -ne 0 && test -z $dir_arg$dst_arg; then  # When -d is used, all remaining arguments are directories to create.  # When -t is used, the destination is already specified.  # Otherwise, the last argument is the destination.  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(umask $mkdir_umask &&         eval \$doit_exec \$mkdirprog $prefixes) ||          test -d $dstdir || exit 1        obsolete_mkdir_used=true      fi    fi  fi  if test -n $dir_arg; then    { test -z $chowncmd || $doit $chowncmd $dst; } &&    { test -z $chgrpcmd || $doit $chgrpcmd $dst; } &&    { test $obsolete_mkdir_used$chowncmd$chgrpcmd = false ||      test -z $chmodcmd || $doit $chmodcmd $mode $dst; } || exit 1  else    # Make a couple of temp file names in the proper directory.    dsttmp=$dstdir/_inst.$$_    rmtmp=$dstdir/_rm.$$_    # Trap to clean up those temp files at exit.    trap 'ret=$?; rm -f $dsttmp $rmtmp && exit $ret' 0    # Copy the file name to the temp name.    (umask $cp_umask && $doit_exec $cpprog $src $dsttmp) &&    # and set any options; do chmod last to preserve setuid bits.    #    # If any of these fail, we abort the whole thing.  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How Linux knows its drivers?
linux;drivers