Freelog Special Edition 1: Linux/CD1.iso/doc/HOWTO/PCMCIA-HOWTO

Text File | 1998-10-14 | 118KB | 3,103 lines

  Linux PCMCIA HOWTO
  David Hinds, [e-mail].
  v2.21, 13 August 1998

  This document describes how to install and use PCMCIA Card Services
  for Linux, and answers some frequently asked questions.  The latest
  version of this document can always be found at <ftp://hyper.stan¡
  ford.edu/pub/pcmcia/doc>.  An HTML version is at <http://hyper.stan¡
  ford.edu/HyperNews/get/pcmcia/home.html>.
  ______________________________________________________________________

  Table of Contents






















































  1. General information and hardware requirements

     1.1 Introduction
     1.2 Copyright notice and disclaimer
     1.3 What is the latest version, and where can I get it?
     1.4 What systems are supported?
     1.5 What cards are supported?
     1.6 When will my new card be supported?
     1.7 Mailing lists and other information sources
     1.8 Why don't you distribute binaries?
     1.9 Why is the package so darned big?

  2. Compilation and installation

     2.1 Prerequisites and kernel setup
     2.2 Installation
     2.3 Startup options
     2.4 System resource settings
     2.5 Notes about specific Linux distributions
        2.5.1 Debian
        2.5.2 Red Hat, and Caldera Open Desktop
        2.5.3 Slackware
        2.5.4 SuSE

  3. Resolving installation and configuration problems

     3.1 Base PCMCIA kernel modules do not load
     3.2 Some client driver modules do not load
     3.3 Interrupt scan failures
     3.4 IO port scan failures
     3.5 Memory probe failures
     3.6 Failure to detect card insertions and removals
     3.7 System resource starvation
     3.8 Resource conflict between two cards
     3.9 Device configuration does not complete

  4. Usage and features

     4.1 Tools for configuring and monitoring PCMCIA devices
        4.1.1 The cardmgr configuration daemon
        4.1.2 The cardctl and cardinfo utilities
        4.1.3 Inserting and ejecting cards
        4.1.4 Card Services and Advanced Power Management
        4.1.5 Shutting down the PCMCIA system
     4.2 Overview of the PCMCIA configuration scripts
     4.3 PCMCIA network adapters
        4.3.1 Network device parameters
        4.3.2 Comments about specific cards
        4.3.3 Diagnosing problems with network adapters
     4.4 PCMCIA serial and modem devices
        4.4.1 Serial device parameters
        4.4.2 Diagnosing problems with serial devices
     4.5 PCMCIA SCSI adapters
        4.5.1 SCSI device parameters
        4.5.2 Comments about specific cards
        4.5.3 Diagnosing problems with SCSI adapters
     4.6 PCMCIA memory cards
        4.6.1 Memory device parameters
        4.6.2 Using flash memory cards
     4.7 PCMCIA ATA/IDE card drives
        4.7.1 ATA/IDE fixed-disk device parameters
        4.7.2 Diagnosing problems with ATA/IDE adapters
     4.8 Multifunction cards

  5. Advanced topics

     5.1 Resource allocation for PCMCIA devices
     5.2 How can I have separate device setups for home and work?
     5.3 Booting from a PCMCIA device
        5.3.1 The pcinitrd helper script
        5.3.2 Creating an initrd boot floppy
        5.3.3 Installing an initrd image on a non-Linux drive

  6. Dealing with unsupported cards

     6.1 Configuring unrecognized cards
     6.2 Adding support for an NE2000-compatible ethernet card
     6.3 PCMCIA floppy interface cards
     6.4 What's up with support for Xircom cards?

  7. Debugging tips and programming information

     7.1 Submitting useful bug reports
     7.2 Low level PCMCIA debugging aids
     7.3 /proc/bus/pccard
     7.4 Writing Card Services drivers for new cards
     7.5 Guidelines for PCMCIA client driver authors
     7.6 Guidelines for Linux distribution maintainers


  ______________________________________________________________________

  1.  General information and hardware requirements

  1.1.  Introduction

  Card Services for Linux is a complete PCMCIA or ``PC Card'' support
  package.  It includes a set of loadable kernel modules that implement
  a version of the Card Services applications program interface, a set
  of client drivers for specific cards, and a card manager daemon that
  can respond to card insertion and removal events, loading and
  unloading drivers on demand.  It supports ``hot swapping'' of most
  card types, so cards can be safely inserted and ejected at any time.

  This software is continually under development.  It probably contains
  bugs, and should be used with caution.  I'll do my best to fix
  problems that are reported to me, but if you don't tell me, I may
  never know.  If you use this code, I hope you will send me your
  experiences, good or bad!

  If you have any suggestions for how this document could be improved,
  please let me know ([e-mail]).


  1.2.  Copyright notice and disclaimer

  Copyright (c) 1998 David A. Hinds

  This document may be reproduced or distributed in any form without my
  prior permission.  Modified versions of this document, including
  translations into other languages, may be freely distributed, provided
  that they are clearly identified as such, and this copyright is
  included intact.

  This document may be included in commercial distributions without my
  prior consent.  While it is not required, I would like to be informed
  of such usage.  If you intend to incorporate this document in a
  published work, please contact me to make sure you have the latest
  available version.

  This document is provided ``AS IS'', with no express or implied
  warranties.  Use the information in this document at your own risk.
  1.3.  What is the latest version, and where can I get it?

  The current major release of Card Services is version 3.0, and minor
  updates or bug fixes are numbered 3.0.1, 3.0.2, and so on.

  Source code for the latest version is available from
  hyper.stanford.edu in the /pub/pcmcia directory, as pcmcia-
  cs-3.0.?.tar.gz.  There will usually be several versions here.  I
  generally only keep the latest minor release for a given major
  release.  New major releases may contain relatively untested code, so
  I also keep the latest version of the previous major release as a
  relatively stable fallback; the current fallback is 2.9.12.  It is up
  to you to decide which version is more appropriate, but the CHANGES
  file will summarize the most important differences.

  hyper.stanford.edu is mirrored at sunsite.unc.edu (and all sunsite
  mirror sites) in /pub/Linux/kernel/pcmcia.

  If you do not feel up to compiling the drivers from scratch, pre-
  compiled drivers are included with current releases of most of the
  major Linux distributions, including Slackware, Debian, Red Hat,
  Caldera, SuSE, and Yggdrasil, among others.


  1.4.  What systems are supported?

  This package should run on almost Intel-based Linux-capable laptop.
  It also runs on Alpha-based platforms (i.e., the DEC Multia).  Work is
  being done to make the package fully dual-endian, so that it will also
  support PowerPC-based platforms (i.e., Apple Powerbooks).  Most common
  socket controllers are supported.  Card docks for desktop systems
  should work as long as they use a supported controller, and are
  plugged directly into the ISA or PCI bus, as opposed to SCSI-to-PCMCIA
  or IDE-to-PCMCIA adapters.  The following controllers are recognized
  by the supplied socket drivers:


  ╖  Cirrus Logic PD6710, PD6720, PD6722, PD6729, PD6730, PD6732, PD6832

  ╖  Intel i82365sl B, C, and DF steps, 82092AA

  ╖  O2Micro OZ6729, OZ6730, OZ6832, OZ6836

  ╖  Omega Micro 82C092G

  ╖  Ricoh RF5C296, RF5C396, RL5C466

  ╖  SMC 34C90

  ╖  Texas Instruments PCI1130, PCI1131, PCI1220, PCI1250A

  ╖  Toshiba ToPIC95, ToPIC97 (experimental)

  ╖  Vadem VG465, VG468, VG469

  ╖  VLSI Technologies 82C146, VCF94365

  ╖  VIA VT83C469

  ╖  Databook DB86082, DB86082A, DB86084, DB86084A, DB86072, DB86082B

  Other controllers that are register compatible with the Intel i82365sl
  will generally work, as well.

  Support for 32-bit CardBus cards is still somewhat experimental.
  Drivers prior to version 3.0 only support 16-bit cards in CardBus
  sockets.  Due to the rapid pace of technological change for laptop
  hardware, new controllers appear frequently, and there may be delays
  between when a new model appears on the market, and when driver
  support becomes available.

  Toshiba recently made available specifications for their ToPIC95 and
  ToPIC97 chipsets.  Work has been hindered by the fact that much of the
  documentation exists only in Japanese.  Full support for these
  chipsets is still experimental.

  The Motorola 6AHC05GA controller used in some Hyundai laptops is not
  supported.  The custom host controller in the HP Omnibook 600 is also
  unsupported.


  1.5.  What cards are supported?

  The current release includes drivers for a variety of ethernet cards,
  a driver for modem and serial port cards, several SCSI adapter
  drivers, a driver for ATA/IDE drive cards, and memory card drivers
  that should support most SRAM cards and some flash cards.  The
  SUPPORTED.CARDS file included with each release of Card Services lists
  all cards that are known to work in at least one actual system.

  The likelihood that a card not on the supported list will work depends
  on the type of card.  Essentially all modems should work with the
  supplied driver.  Some network cards may work if they are OEM versions
  of supported cards.  Other types of IO cards (frame buffers, sound
  cards, etc) will not work until someone writes the appropriate
  drivers.


  1.6.  When will my new card be supported?

  Unfortunately, they usually don't pay me to write device drivers, so
  if you would like to have a driver for your favorite card, you are
  probably going to have to do at least some of the work.  Ideally, I'd
  like to work towards a model like the Linux kernel, where I would be
  responsible mainly for the ``core'' driver code and other authors
  would contribute and maintain client drivers for specific cards.  The
  SUPPORTED.CARDS file mentions some cards for which driver work is
  currently in progress.  I will try to help where I can, but be warned
  that debugging kernel device drivers by email is not particularly
  effective.

  Manufacturers interested in helping provide Linux support for their
  products can contact me about consulting arrangements.


  1.7.  Mailing lists and other information sources

  I used to maintain a database and mailing list of Linux PCMCIA users.
  More recently, I've turned my web page for Linux PCMCIA information
  into a ``HyperNews'' site, with a set of message lists for Linux
  PCMCIA issues.  There are lists for installation and configuration
  issues, for different types of cards, and for programming and
  debugging issues.  The Linux PCMCIA information page is at
  <http://hyper.stanford.edu/HyperNews/get/pcmcia/home.html>.  Users can
  request email notification of new responses to particular questions,
  or notification for all new messages in a given category.  I hope that
  this will become a useful repository of information, for questions
  that go beyond the scope of the HOWTO.

  There is a Linux mailing list devoted to laptop issues, the ``linux-
  laptop'' list.  For more information, send a message containing the
  word ``help'' to [e-mail].  To subscribe, send a
  message containing ``subscribe linux-laptop'' to the same address.
  This mailing list might be a good forum for discussion of Linux PCMCIA
  issues.

  The Linux Laptop Home Page at
  <http://www.cs.utexas.edu/users/kharker/linux-laptop> has links to
  many sites that have information about configuring specific types of
  laptops for Linux.  There is also a searchable database of system
  configuration information.


  1.8.  Why don't you distribute binaries?

  For me, distributing binaries would be a significant hassle.  It is
  complicated because some features can only be selected at compile
  time, and because the modules are somewhat dependent on having the
  ``right'' kernel configuration.  So, I would probably need to
  distribute precompiled modules along with matching kernels.  Beyond
  this, the greatest need for precompiled modules is when installing
  Linux on a clean system.  This typically requires setting up drivers
  so they can be used in the installation process for a particular Linux
  distribution.  Each Linux distribution has its own ideosyncracies, and
  it is not feasible for me to provide boot and root disks for even just
  the common combinations of drivers and distributions.

  PCMCIA is now a part of many of the major Linux distributions,
  including Red Hat, Caldera, Slackware, Yggdrasil, Craftworks, and
  Nascent Technology.


  1.9.  Why is the package so darned big?

  Well, first of all, it isn't actually that large.  All the driver
  modules together take up about 500K of disk space.  The utility
  programs add up to about 70K, and the scripts in /etc/pcmcia are about
  50K.  The core driver modules take up about 55K of system memory.  The
  cardmgr daemon will generally be swapped out except when cards are
  inserted or removed.  The total package size is comparable to
  DOS/Windows Card Services implementations.

  Compared to DOS ``point enablers'', this may still seem like a lot of
  overhead, especially for people that don't plan on using many of the
  features of PCMCIA, such as power management or hot swapping.  Point
  enablers can be tiny because they generally support only one or a
  small set of cards, and also generally support a restricted set of
  host controllers.  If someone were to write a genuinely ``generic''
  modem enabler, it would end up incorporating much of the functionality
  of Card Services, to handle cards from different vendors and the full
  range of host controller variants.


  2.  Compilation and installation

  2.1.  Prerequisites and kernel setup

  Before starting, you should think about whether you really need to
  compile the PCMCIA package yourself.  All common Linux distributions
  come with pre-compiled driver packages.  Generally, you only need to
  install the drivers from scratch if you need a new feature of the
  current drivers, or if you've updated and/or reconfigured your kernel
  in a way that is incompatible with the drivers included with your
  Linux distribution.  While compiling the package is not technically
  difficult, it does require some general Linux familiarity.

  The following things should be installed on your system before you
  begin:
  ╖  A 2.0.* or 2.1.* series kernel source tree.

  ╖  An appropriate set of module utilities.

  ╖  (Optional) the ``XForms'' X11 user interface toolkit.

  The current driver package actually works with most kernel versions
  back to 1.2.8.  However, use with older kernels is deprecated, and
  backwards compatibility with very old kernels may go away at any time.

  You need to have a complete linux source tree for your kernel, not
  just an up-to-date kernel image.  The driver modules contain some
  references to kernel source files.  While you may want to build a new
  kernel to remove unnecessary drivers, installing PCMCIA does not
  require you to do so.

  Current ``stable'' kernel sources and patches are available from
  <ftp://sunsite.unc.edu/pub/Linux/kernel/v2.0>, or from
  <ftp://tsx-11.mit.edu/pub/linux/sources/system/v2.0>.  Development
  kernels can be found in the corresponding v2.1 subdirectories.
  Current module utilities can be found in the same locations.

  In the Linux source tree for 2.0 and 2.1 kernels, the
  Documentation/Changes file describes the versions of all sorts of
  other system components that are required for that kernel release.
  You may want to check through this and verify that your system is up
  to date, especially if you have updated your kernel.  If you are using
  a 2.1 kernel, be sure that you are using the right combination of
  shared libraries and module tools.

  When configuring your kernel, if you plan on using a PCMCIA ethernet
  card, you should turn on networking support but turn off the normal
  Linux network card drivers, including the ``pocket and portable
  adapters''.  The PCMCIA network card drivers are all implemented as
  loadable modules.  Any drivers compiled into your kernel will only
  waste space.

  If you want to use SLIP, PPP, or PLIP, you do need to either configure
  your kernel with these enabled, or use the loadable module versions of
  these drivers.  There is an unfortunate deficiency in the kernel
  config process in 1.2.X kernels, in that it is not possible to set
  configuration options (like SLIP compression) for a loadable module,
  so it is probably better to just link SLIP into the kernel if you need
  it.

  In order to use a PCMCIA token ring adapter, your kernel should be
  configured with ``Token Ring driver support'' (CONFIG_TR) enabled,
  though you should leave CONFIG_IBMTR off.

  If you want to use a PCMCIA IDE adapter, your kernel should be
  configured with CONFIG_BLK_DEV_IDE_PCMCIA enabled, for 1.3.72 through
  2.1.7 kernels.  Older kernels do not support removeable IDE devices;
  newer kernels do not require a special configuration setting.

  If you will be using a PCMCIA SCSI adapter, then enable CONFIG_SCSI
  when configuring your kernel.  Also, enable any top level drivers
  (SCSI disk, tape, cdrom, generic) that you expect to use.  All low-
  level drivers for particular host adapters should be disabled, as they
  will just take up space.

  If you want to modularize a driver that is needed for a PCMCIA device,
  you must modify /etc/pcmcia/config to specify what modules need to be
  loaded for what card types.  For example, if the serial driver is
  modularized, then the serial device definition should be:


       device "serial_cs"
         class "serial" module "misc/serial", "serial_cs"




  This package includes an X-based card status utility called cardinfo.
  This utility is based on a freely distributed user interface toolkit
  called the XForms Library.  This library is available as a separate
  package with most Linux distributions.  If you would like to build
  cardinfo, you should install XForms and all the normal X header files
  and libraries before configuring the PCMCIA package.


  2.2.  Installation

  Here is a synopsis of the installation process:


  ╖  Unpack pcmcia-cs-3.0.?.tar.gz in /usr/src.

  ╖  Run ``make config'' in the new pcmcia-cs-3.0.? directory.

  ╖  Run ``make all'', then ``make install''.

  ╖  Customize the startup script and the option files in /etc/pcmcia
     for your site.

  If you plan to install any contributed client drivers not included in
  the core PCMCIA distribution, unpack each of them in the top-level
  directory of the PCMCIA source tree.  Then follow the normal build
  instructions.  The extra drivers will be compiled and installed
  automatically.

  Running ``make config'' prompts for a few configuration options, and
  checks out your system to verify that it satisfies all prerequisites
  for installing PCMCIA support.  In most cases, you'll be able to just
  accept all the default configuration options.  Be sure to carefully
  check the output of this command in case there are problems.

  If you are compiling the package for installation on another machine,
  specify an alternate target directory when prompted by the configure
  script.  This should be an absolute path.  All filesf will be
  installed relative to this directory.  You will then be able to tar
  this directory tree and copy to your target machine, and unpack
  relative to its root directory to install everything in the proper
  places.

  If you are cross compiling on another machine, you may want to specify
  alternate names for the compiler and linker.  This may also be helpful
  on mixed a.out and ELF systems.  The script will also prompt for
  additional compiler flags for debugging.

  Some of the support utilities (cardctl and cardinfo) can be compiled
  either in ``safe'' or ``trusting'' forms.  The ``safe'' forms prevent
  non-root users from modifying card configurations.  The ``trusting''
  forms permit ordinary users to issue commands to suspend and resume
  cards, reset cards, and change the current configuration scheme.  The
  configuration script will ask if you want the utilities compiled as
  safe or trusting: the default is to be safe.

  There are a few kernel configuration options that affect the PCMCIA
  tools.  The configuration script can deduce these from the running
  kernel (the most common case).  Alternatively, if you are compiling
  for installation on another machine, it can read the configuration
  from a kernel source tree, or each option can be set interactively.
  Running ``make all'' followed by ``make install'' will build and then
  install the kernel modules and utility programs.  Kernel modules are
  installed under /lib/modules/<version>/pcmcia.  The cardmgr and
  cardctl programs are installed in /sbin.  If cardinfo is built, it is
  installed in /usr/bin/X11.

  Configuration files will be installed in the /etc/pcmcia directory.
  If you are installing over an older version, your old config scripts
  will be backed up before being replaced.  The saved scripts will be
  given extensions like *.~1~, *.~2~, and so on.

  If you don't know what kind of host controller your system uses, you
  can use the probe utility in the cardmgr/ subdirectory to determine
  this.  There are two major types: the Databook TCIC-2 type and the
  Intel i82365SL-compatible type.

  In a few cases, the probe command will be unable to determine your
  controller type automatically.  If you have a Halikan NBD 486 system,
  it has a TCIC-2 controller at an unusual location: you'll need to edit
  rc.pcmcia to load the tcic module, and also set the PCIC_OPTS
  parameter to ``tcic_base=0x02c0''.

  On some systems using Cirrus controllers, including the NEC Versa M,
  the BIOS puts the controller in a special suspended state at system
  startup time.  On these systems, the probe command will fail to find
  any known host controller.  If this happens, edit rc.pcmcia and set
  PCIC to i82365, and PCIC_OPTS to ``wakeup=1''.


  2.3.  Startup options

  The PCMCIA startup script recognizes several groups of startup
  options, set via environment variables.  Multiple options should be
  separated by spaces and enclosed in quotes.  Placement of startup
  options depends on the Linux distribution used.  They may be placed
  directly in the startup script, or they may be kept in a separate
  option file.  See the ``Notes about specific Linux distributions'' for
  specifics.  The following variables can be set:


     PCMCIA
        This variable specifies whether PCMCIA support should be started
        up, or not.  If it is set to anything other than ``yes'', then
        the startup script will be disabled.

     PCIC
        This identifies the PC Card Interface Controller driver module.
        There are two options: ``tcic'' or ``i82365''.  Virtually all
        current controllers are in the ``i82365'' group.  This is the
        only mandatory option setting.

     PCIC_OPTS
        This specifies options for the PCIC module.  Some host
        controllers have optional features that may or may not be
        implemented in a particular system.  In some cases, it is
        impossible for the socket driver to detect if these features are
        implemented.  See the corresponding man page for a complete
        description of the available options.

     CORE_OPTS
        This specifies options for the pcmcia_core module, which
        implements the core PC Card driver services.  See ``man
        pcmcia_core'' for more information.

     CARDMGR_OPTS
        This specifies options to be passed to the cardmgr daemon.  See
        ``man cardmgr'' for more information.

     SCHEME
        If set, then the PC Card configuration scheme will be
        initialized to this at driver startup time.  See the ``Overview
        of the PCMCIA configuration scripts'' for a discussion of
        schemes.

  The low level socket drivers, tcic and i82365, have numerous bus
  timing parameters that may need to be adjusted for systems with
  unusual bus clocking.  Symptoms of timing problems include card
  recognition problems, lock-ups under heavy loads, high error rates, or
  poor device performance.  Check the corresponding man pages for more
  details, but here is a brief summary:


  ╖  Cirrus controllers have numerous configurable timing parameters.
     The most important seems to be the cmd_time flag, which determines
     the length of PCMCIA bus cycles.  Fast 486 systems (i.e., DX4-100)
     seem to often benefit from increasing this from 6 (the default) to
     12 or 16.

  ╖  The Cirrus PD6729 PCI controller has the fast_pci flag, which
     should be set if the PCI bus speed is greater than 25 MHz.

  ╖  For Vadem VG-468 controllers and Databook TCIC-2 controllers, the
     async_clock flag changes the relative clocking of PCMCIA bus and
     host bus cycles.  Setting this flag adds extra wait states to some
     operations.  However, I have yet to hear of a laptop that needs
     this.

  ╖  The pcmcia_core module has the cis_speed parameter for changing the
     memory speed used for accessing a card's Card Information Structure
     (CIS).  On some systems with fast bus clocks, increasing this
     parameter (i.e., slowing down card accesses) may be beneficial for
     card recognition problems.

  ╖  This is not a timing issue, but if you have more than one ISA-to-
     PCMCIA controller in your system or extra sockets in a docking
     station, the i82365 module should be loaded with the extra_sockets
     parameter set to 1.  This should not be necessary for detection of
     PCI-to-PCMCIA or PCI-to-CardBus bridges.

  Here are some timing settings for specific systems:


  ╖  On the ARM Pentium-90 or Midwest Micro Soundbook Plus, use
     ``freq_bypass=1 cmd_time=8''.

  ╖  On a Midwest Micro Soundbook Elite, use ``cmd_time=12''.

  ╖  On a Gateway Liberty, try ``cmd_time=16''.


  2.4.  System resource settings

  Card Services should automatically avoid allocating IO ports and
  interrupts already in use by other standard devices.  It will also
  attempt to detect conflicts with unknown devices, but this is not
  completely reliable.  In some cases, you may need to explicitly
  exclude resources for a device in /etc/pcmcia/config.opts.

  Here are some resource settings for specific laptop types.  View this
  list with suspicion: it may give useful hints for solving problems,
  but it is inevitably out of date and certainly contains mistakes.
  Corrections and additions are welcome.
  ╖  On the AMS SoundPro, exclude irq 10.

  ╖  On some AMS TravelPro 5300 models, use memory 0xc8000-0xcffff.

  ╖  On the BMX 486DX2-66, exclude irq 5, irq 9.

  ╖  On the Chicony NB5, use memory 0xda000-0xdffff.

  ╖  On the Compaq Presario 1020, exclude port 0x2f8-0x2ff, irq 3, irq
     5.

  ╖  On the HP Omnibook 4000C, exclude port 0x300-0x30f.

  ╖  On the Micron Millenia Transport, exclude irq 5, irq 9.

  ╖  On the NEC Versa M, exclude irq 9, port 0x2e0-2ff.

  ╖  On the NEC Versa P/75, exclude irq 5, irq 9.

  ╖  On the NEC Versa S, exclude irq 9, irq 12.

  ╖  On the NEC Versa 6000 series, exclude port 0x300-0x33f, irq 9, irq
     10.

  ╖  On the ProStar 9200, Altima Virage, and Acquiline Hurricane
     DX4-100, exclude irq 5, port 0x330-0x35f.  Maybe use memory
     0xd8000-0xdffff.

  ╖  On the Siemens Nixdorf SIMATIC PG 720C, use memory 0xc0000-0xcffff,
     port 0x300-0x3bf.

  ╖  On the TI TravelMate 5000, use memory 0xd4000-0xdffff.

  ╖  On the Toshiba T4900 CT, exclude irq 5, port 0x2e0-0x2e8, port
     0x330-0x338.

  ╖  On the Twinhead 5100, HP 4000, Sharp PC-8700 and PC-8900, exclude
     irq 9 (sound), irq 12.

  ╖  On an MPC 800 Series, exclude irq 5, port 0x300-0x30f for the CD-
     ROM.


  2.5.  Notes about specific Linux distributions

  This section is incomplete.  Corrections and additions are welcome.


  2.5.1.  Debian

  Debian uses a System V boot script arrangement.  The PCMCIA startup
  script is installed as /etc/init.d/pcmcia, and startup options are
  specified in /etc/pcmcia.conf.

  Debian distributes the PCMCIA system in two packages: the ``pcmcia-
  cs'' package contains cardmgr and other tools, man pages, and
  configuration scripts; and the ``pcmcia-modules'' package contains the
  kernel driver modules.


  2.5.2.  Red Hat, and Caldera Open Desktop

  These distributions use a System V boot script organization.  The
  PCMCIA startup script is installed as /etc/rc.d/init.d/pcmcia, and
  boot options are kept in /etc/sysconfig/pcmcia.  Beware that
  installing the Red Hat package may install a default boot option file
  that has PCMCIA disabled.  To enable PCMCIA, the ``PCMCIA'' variable
  should be set to ``yes''.  Red Hat's default syslogd configuration
  will record all interesting messages in /var/log/messages.

  Red Hat's PCMCIA package contains a replacement for the network setup
  script /etc/pcmcia/network, which meshes with the Red Hat network
  control panel.  This is convenient for the case where just one network
  adapter is used, with one set of network parameters, but does not have
  the flexibility of the regular PCMCIA network script.  Compiling and
  installing a clean PCMCIA source distribution will overwrite the
  network script, breaking the link to the network control panel.  If
  you prefer the Red Hat script, either use only Red Hat RPM's, or save
  a copy of the script before installing new driver releases.

  Red Hat bundles their slightly modified PCMCIA source distribution in
  their kernel SRPM, rather than as a separate package.


  2.5.3.  Slackware

  Slackware uses a BSD boot script arrangement.  The PCMCIA startup
  script is installed as /etc/rc.d/rc.pcmcia, and boot options are
  specified in rc.pcmcia itself.  The PCMCIA startup script is invoked
  from /etc/rc.d/rc.M.


  2.5.4.  SuSE

  SuSE uses a System V init script arrangement, with init scripts stored
  under /sbin/init.d.  The PCMCIA startup script is installed as
  /sbin/init.d/pcmcia, and startup options are kept in /etc/rc.config.


  3.  Resolving installation and configuration problems

  This section describes some of the most common failure modes for the
  PCMCIA subsystem.  Try to match your symptoms against the examples.
  This section only describes general failures that are not specific to
  a particular client driver or type of card.

  Before trying to diagnose a problem, you have to know where your
  system log is kept (see ``Notes about specific Linux distributions'').
  You should also be familiar with basic diagnostic tools like dmesg and
  lsmod.  Also, be aware that most driver components (including all the
  kernel modules) have their own individual man pages.

  It is nearly impossible to debug driver problems encountered when
  attempting to install Linux via a PCMCIA device.  Even if you can
  identify the problem based on its symptoms, installation disks are
  difficult to modify, especially without access to a running Linux
  system.  Customization of installation disks is completely dependent
  on the choice of Linux distribution, and is beyond the scope of this
  document.  In general, the best course of action is to install Linux
  using some other means, obtain the latest drivers, and then debug the
  problem if it persists.


  3.1.  Base PCMCIA kernel modules do not load

  Symptoms:

  ╖  Kernel version mismatch errors are reported when the PCMCIA startup
     script runs.

  ╖  After startup, lsmod does not show any PCMCIA modules.

  ╖  cardmgr reports ``no pcmcia driver in /proc/devices'' in the system
     log.

  Kernel modules contain version information that is checked against the
  current kernel when a module is loaded.  The type of checking depends
  on the setting of the CONFIG_MODVERSIONS kernel option.  If this is
  false, then the kernel version number is compiled into each module,
  and insmod checks this for a match with the running kernel.  If
  CONFIG_MODVERSIONS is true, then each symbol exported by the kernel is
  given a sort of checksum.  These codes are all compared against the
  corresponding codes compiled into a module.  The intent was for this
  to make modules less version-dependent, because the checksums would
  only change if a kernel interface changed, and would generally stay
  the same across minor kernel updates.  In practice, the checksums have
  turned out to be even more restrictive, because many kernel interfaces
  depend on compile-time kernel option settings.  Also, the checksums
  turned out to be an excessively pessimistic judge of compatibility.

  The practical upshot of this is that kernel modules are closely tied
  to both the kernel version, and the setting of many kernel
  configuration options.  Generally, a set of modules compiled for one
  2.0.31 kernel will not load against some other 2.0.31 kernel unless
  special care is taken to ensure that the two were built with similar
  configurations.  This makes distribution of precompiled kernel modules
  a tricky business.

  You have several options:


  ╖  If you obtained precompiled drivers as part of a Linux
     distribution, verify that you are using an unmodified kernel as
     supplied with that distribution.  If you intend to use precompiled
     modules, you generally must stick with the corresponding kernel.

  ╖  If you have reconfigured or upgraded your kernel, you will probably
     need to compile and install the PCMCIA package from scratch.  This
     is easily done if you already have the kernel source tree
     installed.  See the PCMCIA-HOWTO for detailed instructions.

  ╖  In some cases, incompatibilities in other system components can
     prevent correct loading of kernel modules.  If you have upgraded
     your own kernel, pay attention to the ``minimal requirements'' for
     module utilities and binutils listed in the Documentation/Changes
     file in the kernel source code tree.


  3.2.  Some client driver modules do not load


  Symptoms:

  ╖  The base modules (pcmcia_core, ds, i82365) load correctly.

  ╖  Inserting a card gives a high beep + low beep pattern.

  ╖  cardmgr reports version mismatch errors in the system log.

  Some of the driver modules require kernel services that may or may not
  be present, depending on kernel configuration.  For instance, the SCSI
  card drivers require that the kernel be configured with SCSI support,
  and the network drivers require a networking kernel.  If a kernel
  lacks a necessary feature, insmod may report undefined symbols and
  refuse to load a particular module. Note that insmod error messages do
  not distinguish between version mismatch errors and missing symbol
  errors.

  Specifically:

  ╖  The serial client driver serial_cs requires the kernel serial
     driver to be enabled with CONFIG_SERIAL.  This driver may be built
     as a module.

  ╖  The SCSI client drivers require that CONFIG_SCSI be enabled, along
     with the appropriate top level driver options (CONFIG_BLK_DEV_SD,
     CONFIG_BLK_DEV_SR, etc for 2.1 kernels).  These may be built as
     modules.

  ╖  The network client drivers require that CONFIG_INET is enabled.
     Kernel networking support cannot be compiled as a module.

  ╖  The token-ring client requires that the kernel be compiled with
     CONFIG_TR enabled.

  There are two ways to proceed:

  ╖  Rebuild your kernel with the necessary features enabled.

  ╖  If the features have been compiled as modules, then modify
     /etc/pcmcia/config to preload these modules.

  The /etc/pcmcia/config file can specify that additional modules need
  to be loaded for a particular client.  For example, for the serial
  driver, one would use:



       device "serial_cs"
         class "serial" module "misc/serial", "serial_cs"




  Module paths are specified relative to the top-level module directory
  for the current kernel version; if no relative path is given, then the
  path defaults to the pcmcia subdirectory.


  3.3.  Interrupt scan failures


  Symptoms:

  ╖  The system locks up when the PCMCIA drivers are loaded, even with
     no cards present.

  ╖  The system log shows a successful host controller probe just before
     the lock-up, but does not show interrupt probe results.

  After identifying the host controller type, the socket driver probes
  for free interrupts.  The probe involves programming the controller
  for each apparently free interrupt, then generating a ``soft''
  interrupt, to see if the interrupt can be detected correctly.  In some
  cases, probing a particular interrupt can interfere with another
  system device.

  The reason for the probe is to identify interrupts which appear to be
  free (i.e., are not reserved by any other Linux device driver), yet
  are either not physically wired to the host controller, or are
  connected to another device that does not have a driver.

  In the system log, a successful probe might look like:

       Intel PCIC probe:
         TI 1130 CardBus at mem 0x10211000, 2 sockets
         ...
         ISA irqs (scanned) = 5,7,9,10 status change on irq 10




  There are two ways to proceed:

  ╖  The interrupt probe can be restricted to a list of interrupts using
     the irq_list parameter for the socket drivers.  For example,
     ``irq_list=5,9,10'' would limit the scan to three interrupts.  All
     PCMCIA devices will be restricted to using these interrupts
     (assuming they pass the probe).  You may need to use trial and
     error to find out which interrupts can be safely probed.

  ╖  The interrupt probe can be disabled entirely by loading the socket
     driver with the ``do_scan=0'' option.  In this case, a default
     interrupt list will be used, which avoids interrupts already
     allocated for other devices.

  In either case, the probe options can be specified using the PCIC_OPTS
  definition in the PCMCIA startup script, for example:



       PCIC_OPTS="irq_list=5,9,10"





  3.4.  IO port scan failures


  Symptoms:

  ╖  The system locks up when cardmgr is first started, even with no
     cards present.

  ╖  The system log shows a successful host controller probe, including
     interrupt probe results, but does not show IO probe results.

  ╖  In some cases, the IO probe will succeed, but report large numbers
     of random exclusions.

  When cardmgr processes IO port ranges listed in
  /etc/pcmcia/config.opts, the kernel probes these ranges to detect
  latent devices that occupy IO space but are not associated with a
  Linux driver.  The probe is read-only, but in rare cases, reading from
  a device may interfere with an important system function, resulting in
  a lock-up.

  Your system user's guide may include a map of system devices, showing
  their IO and memory ranges.  These can be explicitly excluded in
  config.opts.

  Alternatively, if the probe is unreliable on your system, it can be
  disabled by setting CORE_OPTS to ``probe_io=0''.  In this case, you
  should be very careful to specify only genuinely available ranges of
  ports in config.opts, instead of using the default settings.




  3.5.  Memory probe failures


  Symptoms:

  ╖  The core drivers load correctly when no cards are present, with no
     errors in the system log.

  ╖  The system freezes and/or reboots as soon as any card is inserted,
     before any beeps are heard.

  Or alternately:

  ╖  All card insertions generate a high beep followed by a low beep.

  ╖  All cards are identified as ``anonymous memory cards''.

  ╖  The system log reports that various memory ranges have been
     excluded.

  The core modules perform a memory scan at the time of first 16-bit
  card insertion.  This scan can potentially interfere with other memory
  mapped devices.  Also, pre-3.0.0 driver packages perform a more
  aggressive scan than more recent drivers.  The memory window is
  defined in /etc/pcmcia/config.opts.  The default window is large, so
  it may help to restrict the scan to a narrower range.  Reasonable
  ranges to try include 0xd0000-0xdffff, 0xc0000-0xcffff,
  0xc8000-0xcffff, or 0xd8000-0xdffff.

  If you have DOS or Windows PCMCIA drivers, you may be able to deduce
  what memory region those drivers use.  Note that DOS memory addresses
  are often specified in ``segment'' form, which leaves off the final
  hex digit (so an absolute address of 0xd0000 might be given as
  0xd000).  Be sure to add the extra digit back when making changes to
  config.opts.

  In unusual cases, a memory probe failure can indicate a timing
  register setup problem with the host controller.  See the ``Startup
  options'' section for information about dealing with common timing
  problems.

  CardBus bridges can allocate memory windows outside of the 640KB-1MB
  ``memory hole'' in the ISA bus architecture.  It is generally a good
  idea to configure CardBus bridges to use high memory windows, because
  these are unlikely to conflict with other devices.  Also, CardBus
  cards may require large memory windows, which may be difficult or
  impossible to fit into low memory.  Card Services will preferentially
  allocate windows in high memory for CardBus bridges, if both low and
  high memory windows are defined in config.opts.  The default
  config.opts now includes a high memory window of
  0xa0000000-0xa0ffffff.  If you have a CardBus bridge and have upgraded
  from an older PCMCIA driver release, add this memory window if it is
  not already defined.


  3.6.  Failure to detect card insertions and removals

  Symptoms:

  ╖  Cards are detected and configured properly if present at boot time.

  ╖  The drivers do not respond to insertion and removal events, either
     by recording events in the system log, or by beeping.

  In most cases, the socket driver (i82365 or tcic) will automatically
  probe and select an appropriate interrupt to signal card status
  changes.  The automatic interrupt probe doesn't work on some Intel-
  compatible controllers, including Cirrus chips and the chips used in
  some IBM ThinkPads.  If a device is inactive at probe time, its
  interrupt may also appear to be available.  In these cases, the socket
  driver may pick an interrupt that is used by another device.

  With the i82365 and tcic drivers, the irq_list option can be used to
  limit the interrupts that will be tested.  This list limits the set of
  interrupts that can be used by PCMCIA cards as well as for monitoring
  card status changes.  The cs_irq option can also be used to explicitly
  set the interrupt to be used for monitoring card status changes.

  If you can't find an interrupt number that works, there is also a
  polled status mode: both i82365 and tcic will accept a
  poll_interval=100 option, to poll for card status changes once per
  second.  This option should also be used if your system has a shortage
  of interrupts available for use by PCMCIA cards.  Especially for
  systems with more than one host controller, there is little point in
  dedicating interrupts for monitoring card status changes.

  All these options should be set in the PCIC_OPTS= line in either
  /etc/rc.d/rc.pcmcia or /etc/sysconfig/pcmcia, depending on your site
  setup.


  3.7.  System resource starvation


  Symptoms:


  ╖  When a card is inserted, it is identified correctly but cannot be
     configured (high/low beep pattern).

  ╖  One of the following messages will appear in the system log:


       RequestIRQ: Resource in use
       RequestWindow: Resource in use
       GetNextTuple: No more items
       could not allocate nn IO ports for CardBus socket n
       could not allocate nnK memory for CardBus socket n




  Interrupt starvation often indicates a problem with the interrupt
  probe (see ``Interrupt probe failures'').  In some cases, the probe
  will seem to work, but only report one or two available interrupts.
  Check your system log to see if the scan results look sensible.
  Disabling the probe and selecting interrupts manually should help.

  If the interrupt probe is not working properly, the socket driver may
  allocate an interrupt for monitoring card insertions, even when
  interrupts are too scarce for this to be a good idea.  In that case,
  you can switch the controller to polled mode by setting PCIC_OPTS to
  ``poll_interval=100'.  Or, if you have a CardBus controller, try
  ``pci_csc=1'', which selects a PCI interrupt (if available) for card
  status changes.

  IO port starvation is fairly uncommon, but sometimes happens with
  cards that require large, contiguous, aligned regions of IO port
  space, or that only recognize a few specific IO port positions.  The
  default IO port ranges in /etc/pcmcia/config.opts are normally
  sufficient, but may be extended.  In rare cases, starvation may
  indicate that the IO port probe failed (see ``IO port scan
  failures'').

  Memory starvation is also uncommon with the default memory window
  settings in config.opts.  CardBus cards may require larger memory
  regions than typical 16-bit cards.  Since CardBus memory windows can
  be mapped anywhere in the host's PCI address space (rather than just
  in the 640K-1MB ``hole'' in PC systems), it is helpful to specify
  large memory windows in high memory, such as 0xa0000000-0xa0ffffff.


  3.8.  Resource conflict between two cards


  Symptoms:

  ╖  Two cards each work fine when used separately.

  ╖  When both cards are inserted, only one works.

  This usually indicates a resource conflict with a system device that
  Linux does not know about.  PCMCIA devices are dynamically configured,
  so, for example, interrupts are allocated as needed, rather than
  specifically assigned to particular cards or sockets.  Given a list of
  resources that appear to be available, cards are assigned resources in
  the order they are configured.  In this case, the card configured last
  is being assigned a resource that in fact is not free.

  Check the system log to see what resources are used by the non-working
  card.  Exclude these in /etc/pcmcia/config.opts, and restart the
  cardmgr daemon to reload the resource database.


  3.9.  Device configuration does not complete


  Symptoms:

  ╖  When a card is inserted, exactly one high beep is heard.

  ╖  Subsequent card insertions and removals may be ignored.

  This indicates that the card was identified successfully, however,
  cardmgr has been unable to complete the configuration process for some
  reason.  The most likely reason is that a step in the card setup
  script has blocked.  A good example would be the network script
  blocking if a network card is inserted with no actual network hookup
  present.

  To pinpoint the problem, you can manually run a setup script to see
  where it is blocking.  The scripts are in the /etc/pcmcia directory.
  They take two parameters: a device name, and an action.  The cardmgr
  daemon records the configuration commands in the system log.  For
  example, if the system log shows that the command ``./network start
  eth0'' was the last command executed by cardmgr, the following
  commands would trace the script:



       cd /etc/pcmcia
       sh -x ./network start eth0






  4.  Usage and features

  4.1.  Tools for configuring and monitoring PCMCIA devices

  If the modules are all loaded correctly, the output of the lsmod
  command should look like the following, when no cards are inserted:



       Module                  Size  Used by
       ds                      5640   2
       i82365                 15452   2
       pcmcia_core            30012   3  [ds i82365]




  The system log should also include output from the socket driver
  describing the host controller(s) found and the number of sockets
  detected.


  4.1.1.  The cardmgr configuration daemon

  The cardmgr daemon is responsible for monitoring PCMCIA sockets,
  loading client drivers when needed, and running user-level scripts in
  response to card insertions and removals.  It records its actions in
  the system log, but also uses beeps to signal card status changes.
  The tones of the beeps indicate success or failure of particular
  configuration steps.  Two high beeps indicate that a card was
  identified and configured successfully.  A high beep followed by a low
  beep indicates that a card was identified, but could not be configured
  for some reason.  One low beep indicates that a card could not be
  identified.

  Cardmgr records device information for each socket in /var/run/stab.
  Here is a sample /var/run/stab listing:



       Socket 0: Adaptec APA-1460 SlimSCSI
       0       scsi    aha152x_cs      0       sda     8       0
       0       scsi    aha152x_cs      1       scd0    11      0
       Socket 1: Serial or Modem Card
       1       serial  serial_cs       0       ttyS1   5       65




  For the lines describing devices, the first field is the socket, the
  second is the device class, the third is the driver name, the fourth
  is used to number multiple devices associated with the same driver,
  the fifth is the device name, and the final two fields are the major
  and minor device numbers for this device (if applicable).

  The cardmgr daemon configures cards based on a database of known card
  types kept in /etc/pcmcia/config.  This file describes the various
  client drivers, then describes how to identify various cards, and
  which driver(s) belong with which cards.  The format of this file is
  described in the pcmcia(5) man page.


  4.1.2.  The cardctl and cardinfo utilities



  The cardctl command can be used to check the status of a socket, or to
  see how it is configured.  It can also be used to alter the
  configuration status of a card.  Here is an example of the output of
  the ``cardctl config'' command:



       Socket 0:
         not configured
       Socket 1:
         Vcc = 5.0, Vpp1 = 0.0, Vpp2 = 0.0
         Card type is memory and I/O
         IRQ 3 is dynamic shared, level mode, enabled
         Speaker output is enabled
         Function 0:
           Config register base = 0x0800
             Option = 0x63, status = 0x08
           I/O window 1: 0x0280 to 0x02bf, auto sized
           I/O window 2: 0x02f8 to 0x02ff, 8 bit




  Or ``cardctl ident'', to get card identification information:



       Socket 0:
         no product info available
       Socket 1:
         product info: "LINKSYS", "PCMLM336", "A", "0040052D6400"
         manfid: 0x0143, 0xc0ab
         function: 0 (multifunction)




  The ``cardctl suspend'' and ``cardctl resume'' commands can be used to
  shut down a card without unloading its associated drivers.  The
  ``cardctl reset'' command attempts to reset and reconfigure a card.
  ``cardctl insert'' and ``cardctl eject'' mimic the actions performed
  when a card is physically inserted or ejected, including loading or
  unloading drivers, and configuring or shutting down devices.

  If you are running X, the cardinfo utility produces a graphical
  display showing the current status of all PCMCIA sockets, similar in
  content to ``cardctl config''.  It also provides a graphical interface
  to most other cardctl functions.


  4.1.3.  Inserting and ejecting cards

  In theory, you can insert and remove PCMCIA cards at any time.
  However, it is a good idea not to eject a card that is currently being
  used by an application program.  Kernels older than 1.1.77 would often
  lock up when serial/modem cards were ejected, but this should be fixed
  now.


  4.1.4.  Card Services and Advanced Power Management

  Card Services can be compiled with support for APM (Advanced Power
  Management) if you've installed this package on your system.  APM is
  incorporated into 1.3.46 and later kernels.  It is currently being
  maintained by Rick Faith ([e-mail]), and APM tools can be
  obtained from <ftp://ftp.cs.unc.edu/pub/users/faith/linux>.  The
  PCMCIA modules will automatically be configured for APM if a
  compatible version is detected on your system.

  Without resorting to APM, you can do ``cardctl suspend'' before
  suspending your laptop, and ``cardctl resume'' after resuming, to
  properly shut down and restart your PCMCIA cards.  This will not work
  with a modem that is in use, because the serial driver isn't able to
  save and restore the modem operating parameters.

  APM seems to be unstable on some systems.  If you experience trouble
  with APM and PCMCIA on your system, try to narrow down the problem to
  one package or the other before reporting a bug.

  Some drivers, notably the PCMCIA SCSI drivers, cannot recover from a
  suspend/resume cycle.  When using a PCMCIA SCSI card, always use
  ``cardctl eject'' prior to suspending the system.


  4.1.5.  Shutting down the PCMCIA system

  To unload the entire PCMCIA package, invoke rc.pcmcia with:



       /etc/rc.d/rc.pcmcia stop




  This script will take several seconds to run, to give all client
  drivers time to shut down gracefully.  If a device is currently in
  use, the shutdown will be incomplete, and some kernel modules may not
  be unloaded.  To avoid this, use ``cardctl eject'' to shut down all
  sockets before invoking rc.pcmcia.  The exit status of the cardctl
  command will indicate if any sockets could not be shut down.


  4.2.  Overview of the PCMCIA configuration scripts

  Each PCMCIA device has an associated ``class'' that describes how it
  should be configured and managed.  Classes are associated with device
  drivers in /etc/pcmcia/config.  There are currently five IO device
  classes (network, SCSI, cdrom, fixed disk, and serial) and two memory
  device classes (memory and FTL).  For each class, there are two
  scripts in /etc/pcmcia: a main configuration script (i.e.,
  /etc/pcmcia/scsi for SCSI devices), and an options script (i.e.,
  /etc/pcmcia/scsi.opts).  The main script for a device will be invoked
  to configure that device when a card is inserted, and to shut down the
  device when the card is removed.  For cards with several associated
  devices, the script will be invoked for each device.

  The config scripts start by extracting some information about a device
  from /var/run/stab.  Each script constructs a ``device address'', that
  uniquely describes the device it has been asked to configure, in the
  ADDRESS shell variable.  This is passed to the *.opts script, which
  should return information about how a device at this address should be
  configured.  For some devices, the device address is just the socket
  number.  For others, it includes extra information that may be useful
  in deciding how to configure the device.  For example, network devices
  pass their hardware ethernet address as part of the device address, so
  the network.opts script could use this to select from several
  different configurations.

  The first part of all device addresses is the current PCMCIA
  ``scheme''.  This parameter is used to support multiple sets of device
  configurations based on a single external user-specified variable.
  One use of schemes would be to have a ``home'' scheme, and a ``work''
  scheme, which would include different sets of network configuration
  parameters.  The current scheme is selected using the ``cardctl
  scheme'' command.  The default if no scheme is set is ``default''.

  As a general rule, when configuring Linux for a laptop, PCMCIA devices
  should only be configured from the PCMCIA device scripts.  Do not try
  to configure a PCMCIA device the same way you would configure a
  permanently attached device.  However, some Linux distributions
  provide PCMCIA packages that are hooked into those distributions' own
  device configuration tools.  In that case, some of the following
  sections may not apply; ideally, this will be documented by the
  distribution maintainers.


  4.3.  PCMCIA network adapters

  Linux ethernet-type network interfaces normally have names like eth0,
  eth1, and so on.  Token-ring adapters are handled similarly, however
  they are named tr0, tr1, and so on.  The ifconfig command is used to
  view or modify the state of a network interface.  A peculiarity of
  Linux is that network interfaces do not have corresponding device
  files under /dev, so do not be surprised when you do not find them.

  When an ethernet card is detected, it will be assigned the first free
  interface name, which will normally be eth0.  Cardmgr will run the
  /etc/pcmcia/network script to configure the interface, which normally
  reads network settings from /etc/pcmcia/network.opts.  The network and
  network.opts scripts will be executed only when your ethernet card is
  actually present.  If your system has an automatic network
  configuration facility, it may or may not be PCMCIA-aware.  Consult
  the documentation of your Linux distribution and the ``Notes about
  specific Linux distributions''  to determine if PCMCIA network devices
  should be configured with the automatic tools, or by editing
  network.opts.

  The device address passed to network.opts consists of four comma-
  separated fields: the scheme, the socket number, the device instance,
  and the card's hardware ethernet address.  The device instance is used
  to number devices for cards that have several network interfaces, so
  it will usually be 0.  If you have several network cards used for
  different purposes, one option would be to configure the cards based
  on socket position, as in:



       case "$ADDRESS" in
       *,0,*,*)
           # definitions for network card in socket 0
           ;;
       *,1,*,*)
           # definitions for network card in socket 1
           ;;
       esac




  Alternatively, they could be configured using their hardware
  addresses, as in:






  case "$ADDRESS" in
  *,*,*,00:80:C8:76:00:B1)
      # definitions for a D-Link card
      ;;
  *,*,*,08:00:5A:44:80:01)
      # definitions for an IBM card
  esac





  4.3.1.  Network device parameters

  The following parameters can be defined in network.opts:


     IF_PORT
        Specifies the ethernet transceiver type, for cards that do not
        autodetect.  See ``man ifport'' for transceiver names.

     BOOTP
        A boolean (y/n) value: indicates if the host's IP address and
        routing information should be obtained using the BOOTP protocol.

     IPADDR
        The IP address for this interface.

     NETMASK, BROADCAST, NETWORK
        Basic network parameters: see the networking HOWTO for more
        information.

     GATEWAY
        The IP address of a gateway for this host's subnet.  Packets
        with destinations outside this subnet will be routed to this
        gateway.

     DOMAIN
        The local network domain name for this host, to be used in
        creating /etc/resolv.conf.

     SEARCH
        A search list for host name lookup, to be added to
        /etc/resolv.conf.  DOMAIN and SEARCH are mutually exclusive: see
        ``man resolver'' for more information.

     DNS_1, DNS_2, DNS_3
        Host names or IP addresses for nameservers for this interface,
        to be added to /etc/resolv.conf

     MOUNTS
        A list of NFS mount points to be mounted for this interface.

     IPX_FRAME, IPX_NETNUM
        For IPX networks: the frame type and network number, passed to
        the ipx_interface command.

  For example:








  case "$ADDRESS" in
  *,*,*,*)
      IF_PORT="10base2"
      BOOTP="n"
      IPADDR="10.0.0.1"
      NETMASK="255.255.255.0"
      NETWORK="10.0.0.0"
      BROADCAST="10.0.0.255"
      GATEWAY="10.0.0.1"
      DOMAIN="domain.org"
      DNS_1="dns1.domain.org"
      ;;
  esac




  To automatically mount and unmount NFS filesystems, first add all
  these filesystems to /etc/fstab, but include noauto in the mount
  options.  In network.opts, list the filesystem mount points in the
  MOUNTS variable.  It is especially important to use either cardctl or
  cardinfo to shut down a network card when NFS mounts are active.  It
  is not possible to cleanly unmount NFS filesystems if a network card
  is simply ejected without warning.

  In addition to the usual network configuration parameters, the
  network.opts script can specify extra actions to be taken after an
  interface is configured, or before an interface is shut down.  If
  network.opts defines a shell function called start_fn, it will be
  invoked by the network script after the interface is configured, and
  the interface name will be passed to the function as its first (and
  only) argument.  Similarly, if it is defined, stop_fn will be invoked
  before shutting down an interface.

  The transceiver type can be selected using the IF_PORT setting.  This
  can either be a numeric value as in previous PCMCIA releases, or a
  keyword identifying the transceiver type.  All the network drivers
  default to either autodetect the interface if possible, or 10baseT
  otherwise.  The ifport command can be used to check or set the current
  transceiver type.  For example:



       # ifport eth0 10base2
       #
       # ifport eth0
       eth0    2 (10base2)




  Current releases of the 3c589 driver attempt to autodetect the network
  connection, but this doesn't seem to be completely functional yet.
  For autodetection to work, the network cable should be connected to
  the card when the card is configured.  Alternatively, once the network
  is connected, you can force the driver to check the connection with:



       ifconfig eth0 down up






  4.3.2.  Comments about specific cards



  ╖  With IBM CCAE and Socket EA cards, the transceiver type (10base2,
     10baseT, AUI) needs to be set when the network device is
     configured.  Make sure that the transceiver type reported in the
     system log matches your connection.

  ╖  The drivers for SMC, Megahertz, Ositech, and 3Com cards should
     autodetect the attached network type (10base2 or 10baseT).  Setting
     the transceiver type when the driver is loaded serves to define the
     card's ``first guess''.

  ╖  The Farallon EtherWave is actually based on the 3Com 3c589, with a
     special transceiver.  Though the EtherWave uses 10baseT-style
     connections, its transceiver requires that the 3c589 be configured
     in 10base2 mode.

  ╖  If you have trouble with an IBM CCAE, NE4100, Thomas Conrad, or
     Kingston adapter, try increasing the memory access time with the
     mem_speed=# option to the pcnet_cs module.  An example of how to do
     this is given in the standard config.opts file.  Try speeds of up
     to 1000 (in nanoseconds).

  ╖  For the New Media Ethernet adapter, on some systems, it may be
     necessary to increase the IO port access time with the io_speed=#
     option when the pcmcia_core module is loaded.  Edit CORE_OPTS in
     the startup script  to set this option.

  ╖  The multicast support in the New Media Ethernet driver is
     incomplete.  The latest driver will function with multicast
     kernels, but will ignore multicast packets.  Promiscuous mode
     should work properly.

  ╖  The driver used by the IBM and 3Com token ring adapters seems to
     behave very badly if the cards are not connected to a ring when
     they get initialized.  Always connect these cards to the net before
     they are powered up.  This driver also requires free IO ports in
     the range of 0xa20-0xa27.  On some systems, the automatic IO port
     conflict checker will incorrectly determine that this port range is
     unavailable.  In that case, the port check can be disabled by
     loading the pcmcia_core module with probe_io=0.

  ╖  Newer Linksys and D-Link cards have a unique way of selecting the
     transceiver type that isn't handled by the Linux drivers.  One
     workaround is to boot DOS and use the vendor-supplied utility to
     select the transceiver, then warm boot Linux.  I am looking for
     beta testers for a Linux utility to perform this function.

  ╖  For WaveLAN wireless network adapters, Jean Tourrilhes
     ([e-mail]) has put together a wireless HOWTO at
     <http://www-uk.hpl.hp.com/people/jt/Linux/Wavelan.html>.


  4.3.3.  Diagnosing problems with network adapters



  ╖  Is your card recognized as an ethernet card?  Check the system log
     and make sure that cardmgr identifies the card correctly and starts
     up one of the network drivers.  If it doesn't, your card might
     still be usable if it is compatible with a supported card.  This
     will be most easily done if the card claims to be ``NE2000
     compatible''.

  ╖  Is the card configured properly?  If you are using a supported
     card, and it was recognized by cardmgr, but still doesn't work,
     there might be an interrupt or port conflict with another device.
     Find out what resources the card is using (from the system log),
     and try excluding these in /etc/pcmcia/config.opts to force the
     card to use something different.

  ╖  If your card seems to be configured properly, but sometimes locks
     up, particularly under high load, you may need to try changing your
     socket driver timing parameters.  See the ``Startup options''
     section for more information.

  ╖  If you get ``network unreachable'' messages when you try to access
     the network, then the routing information specified in
     /etc/pcmcia/network.opts is incorrect.  This message is an
     absolutely foolproof indication of a routing error.  On the other
     hand, mis-configured cards will usually fail silently.

  ╖  To diagnose problems in /etc/pcmcia/network.opts, start by trying
     to ping other systems on the same subnet using their IP addresses.
     Then try to ping your gateway, and then machines on other subnets.
     Ping machines by name only after trying these simpler tests.

  ╖  Make sure your problem is really a PCMCIA one.  It may help to see
     see if the card works under DOS with the vendor's drivers.  Double
     check your modifications to the /etc/pcmcia/network.opts script.
     Make sure your drop cable, ``T'' jack, terminator, etc are working.


  4.4.  PCMCIA serial and modem devices

  Linux serial devices are accessed via the /dev/cua* and /dev/ttyS*
  special device files.  The ttyS* devices are for incoming connections,
  such as directly connected terminals.  The cua* devices are for
  outgoing connections, such as modems.  Each physical serial port has
  both a ttyS and a cua device file: it is up to you to pick the
  appropriate device for your application.  The configuration of a
  serial device can be examined and modified with the setserial command.

  When a serial or modem card is detected, it will be assigned to the
  first available serial device slot.  This will usually be /dev/ttyS1
  (cua1) or /dev/ttyS2 (cua2), depending on the number of built-in
  serial ports.  The ttyS* device is the one reported in /var/run/stab.
  The default serial device option script, /etc/pcmcia/serial.opts, will
  link the corresponding cua* device file to /dev/modem as a
  convenience.

  Do not try to use /etc/rc.d/rc.serial to configure a PCMCIA modem.
  This script should only be used to configure non-removable devices.
  Modify /etc/pcmcia/serial.opts if you want to do anything special to
  set up your modem.  Also, do not try to change the IO port and
  interrupt settings of a serial device using setserial.  This would
  tell the serial driver to look for the device in a different place,
  but would not change how the card's hardware is actually configured.
  The serial configuration script allows you to specify other setserial
  options, as well as whether a line should be added to /etc/inittab for
  this port.

  The device address passed to serial.opts has three comma-separated
  fields: the first is the scheme, the second  is the socket number, and
  the third is the device instance.  The device instance may take
  several values for cards that support multiple serial ports, but for
  single-port cards, it will always be 0.  If you commonly use more than
  one modem, you may want to specify different settings based on socket
  position, as in:

       case "$ADDRESS" in
       *,0,*)
           # Options for modem in socket 0
           LINK=/dev/modem0
           ;;
       *,1,*)
           # Options for modem in socket 1
           LINK=/dev/modem1
           ;;
       esac




  If a PCMCIA modem is already configured when Linux boots, it may be
  incorrectly identified as an ordinary built-in serial port.  This is
  harmless, however, when the PCMCIA drivers take control of the modem,
  it will be assigned a different device slot.  It is best to either
  parse /var/run/stab or use /dev/modem, rather than expecting a PCMCIA
  modem to always have the same device assignment.

  If you configure your kernel to load the basic Linux serial port
  driver as a module, you must edit /etc/pcmcia/config to indicate that
  this module must be loaded.  Edit the serial device entry to read:



       device "serial_cs"
         class "serial" module "misc/serial", "serial_cs"





  4.4.1.  Serial device parameters

  The following parameters can be defined in serial.opts:

     LINK
        Specifies a path for a symbolic link to be created to the
        ``dialout'' or /dev/cua* device.

     SERIAL_OPTS
        Specifies options to be passed to the setserial command.

     INITTAB
        If specified, this will be used to construct an inittab entry
        for the device.

  For example:



       case "$ADDRESS" in
       *,*,*,*)
           LINK="/dev/modem"
           SERIAL_OPTS=""
           INITTAB="/sbin/getty"








  4.4.2.  Diagnosing problems with serial devices



  ╖  Is your card recognized as a modem?  Check the system log and make
     sure that cardmgr identifies the card correctly and starts up the
     serial_cs driver.  If it doesn't, you may need to add a new entry
     to your /etc/pcmcia/config file so that it will be identified
     properly.  See the ``Configuring unrecognized cards'' section for
     details.

  ╖  Is the modem configured successfully by serial_cs?  Again, check
     the system log and look for messages from the serial_cs driver.  If
     you see ``register_serial() failed'', you may have an I/O port
     conflict with another device.  Another tip-off of a conflict is if
     the device is reported to be an 8250; most modern modems should be
     identified as 16550A UART's.  If you think you're seeing a port
     conflict, edit /etc/pcmcia/config.opts and exclude the port range
     that was allocated for the modem.

  ╖  Is there an interrupt conflict?  If the system log looks good, but
     the modem just doesn't seem to work, try using setserial to change
     the irq to 0, and see if the modem works.  This causes the serial
     driver to use a slower polled mode instead of using interrupts.  If
     this seems to fix the problem, it is likely that some other device
     in your system is using the interrupt selected by serial_cs.  You
     should add a line to /etc/pcmcia/config.opts to exclude this
     interrupt.

  ╖  If the modem seems to work only very, very slowly, this is an
     almost certain indicator of an interrupt conflict.

  ╖  Make sure your problem is really a PCMCIA one.  It may help to see
     if the card works under DOS with the vendor's drivers.  Also, don't
     test the card with something complex like SLIP or PPP until you are
     sure you can make simple connections.  If simple things work but
     SLIP does not, your problem is most likely with SLIP, not with
     PCMCIA.

  ╖  If you get kernel messages indicating that the serial_cs module
     cannot be loaded, it means that your kernel does not have serial
     device support.  If you have compiled the serial driver as a
     module, you must modify /etc/pcmcia/config to indicate that the
     serial module should be loaded before serial_cs.


  4.5.  PCMCIA SCSI adapters

  All the currently supported PCMCIA SCSI cards are work-alikes of one
  of the following ISA bus cards: the Qlogic, the Adaptec AHA-152X, or
  the Future Domain TMC-16x0.  The PCMCIA drivers are built by linking
  some PCMCIA-specific code (in qlogic_cs.c, toaster_cs.c, or
  fdomain_cs.c) with the normal Linux SCSI driver.  Due to limitations
  in the Linux SCSI driver model, only one removable card per driver is
  supported.

  When a new SCSI host adapter is detected, the SCSI drivers will probe
  for devices.  Check the system log to make sure your devices are
  detected properly.  New SCSI devices will be assigned to the first
  available SCSI device files.  The first SCSI disk will be /dev/sda,
  the first SCSI tape will be /dev/st0, and the first CD-ROM will be
  /dev/scd0.

  With 1.3.X and later kernels, the PCMCIA core drivers are able to find
  out from the kernel which SCSI devices are connected to a card.  They
  will be listed in /var/run/stab, and the SCSI configuration script,
  /etc/pcmcia/scsi, will be called once for each attached device, to
  either configure or shut down that device.  The default script does
  not take any actions to configure SCSI devices, but will properly
  unmount filesystems on SCSI devices when a card is removed.

  With 1.2.X kernels, the PCMCIA drivers cannot automatically deduce
  which devices are associated with a particular SCSI adapter.  Instead,
  if you have one normal SCSI device configuration, you may list these
  devices in /etc/pcmcia/scsi.opts.  For example, if you normally have a
  SCSI disk and a CD-ROM, you would use:



       # For 1.2 kernels: list of attached devices
       SCSI_DEVICES="sda scd0"




  The device addresses passed to scsi.opts are complicated, because of
  the variety of things that can be attached to a SCSI adapter.
  Addresses consist of either six or seven comma-separated fields: the
  current scheme, the device type, the socket number, the SCSI channel,
  ID, and logical unit number, and optionally, the partition number.
  The device type will be ``sd'' for disks, ``st'' for tapes, ``sr'' for
  CD-ROM devices, and ``sg'' for generic SCSI devices.  For most setups,
  the SCSI channel and logical unit number will be 0.  For disk devices
  with several partitions, scsi.opts will first be called for the whole
  device, with a five-field address.  The script should set the PARTS
  variable to a list of partitions.  Then, scsi.opts will be called for
  each partition, with the longer seven-field addresses.

  If your kernel does not have a top-level driver (disk, tape, etc) for
  a particular SCSI device, then the device will not be configured by
  the PCMCIA drivers.  As a side effect, the device's name in
  /var/run/stab will be something like ``sd#nnnn'' where ``nnnn'' is a
  four-digit hex number.  This happens when cardmgr is unable to
  translate a SCSI device ID into a corresponding Linux device name.

  It is possible to modularize the top-level SCSI drivers so that they
  are loaded on demand.  To do so, you need to edit /etc/pcmcia/config
  to tell cardmgr which extra modules need to be loaded when your
  adapter is configured.  For example:



       device "aha152x_cs"
         class "scsi" module "scsi/scsi_mod", "scsi/sd_mod", "aha152x_cs"




  would say to load the core SCSI module and the top-level disk driver
  module before loading the regular PCMCIA driver module.  The PCMCIA
  Configure script will not automatically detect modularized SCSI
  modules, so you will need use the manual configure option to enable
  SCSI support.

  Always turn on SCSI devices before powering up your laptop, or before
  inserting the adapter card, so that the SCSI bus is properly
  terminated when the adapter is configured.  Also be very careful about
  ejecting a SCSI adapter.  Be sure that all associated SCSI devices are
  unmounted and closed before ejecting the card.  The best way to ensure
  this is to use either cardctl or cardinfo to request card removal
  before physically ejecting the card.  For now, all SCSI devices should
  be powered up before plugging in a SCSI adapter, and should stay
  connected until after you unplug the adapter and/or power down your
  laptop.

  There is a potential complication when using these cards that does not
  arise with ordinary ISA bus adapters.  The SCSI bus carries a
  ``termination power'' signal that is necessary for proper operation of
  ordinary passive SCSI terminators.  PCMCIA SCSI adapters do not supply
  termination power, so if it is required, an external device must
  supply it.  Some external SCSI devices may be configured to supply
  termination power.  Others, such as the Zip Drive and the Syquest EZ-
  Drive, use active terminators that do not depend on it.  In some
  cases, it may be necessary to use a special terminator block such as
  the APS SCSI Sentry 2, which has an external power supply.  When
  configuring your SCSI device chain, be aware of whether or not any of
  your devices require or can provide termination power.


  4.5.1.  SCSI device parameters

  The following parameters can be defined in scsi.opts:

     DO_FSTAB
        A boolean (y/n) setting: specifies if an entry should be added
        to /etc/fstab for this device.

     DO_FSCK
        A boolean (y/n) setting: specifies if the filesystem should be
        checked before being mounted, with ``fsck -Ta''.

     DO_MOUNT
        A boolean (y/n) setting: specifies if this device should be
        automatically mounted at card insertion time.

     FSTYPE, OPTS, MOUNTPT
        The filesystem type, mount options, and mount point to be used
        for the fstab entry and/or mounting the device.

  For example, here is a script for configuring a disk device at SCSI ID
  3, with two partitions, and a CD-ROM at SCSI ID 6:



























  case "$ADDRESS" in
  *,sd,*,0,3,0)
      # This device has two partitions...
      PARTS="1 2"
      ;;
  *,sd,*,0,3,0,1)
      # Options for partition 1:
      #  update /etc/fstab, and mount an ext2 fs on /usr1
      DO_FSTAB="y" ; DO_FSCK="y" ; DO_MOUNT="y"
      FSTYPE="ext2"
      OPTS=""
      MOUNTPT="/usr1"
      ;;
  *,sd,*,0,3,0,2)
      # Options for partition 2:
      #  update /etc/fstab, and mount an MS-DOS fs on /usr2
      DO_FSTAB="y" ; DO_FSCK="y" ; DO_MOUNT="y"
      FSTYPE="msdos"
      OPTS=""
      MOUNTPT="/usr2"
      ;;
  *,sr,*,0,6,0)
      # Options for CD-ROM at SCSI ID 6
      PARTS=""
      DO_FSTAB="y" ; DO_FSCK="n" ; DO_MOUNT="y"
      FSTYPE="iso9660"
      OPTS="ro"
      MOUNTPT="/cdrom"
      ;;
  esac





  4.5.2.  Comments about specific cards



  ╖  The Adaptec APA-1480 CardBus card needs a large IO port window (256
     contiguous ports aligned on a 256-port boundary).  It may be
     necessary to expand the IO port regions in /etc/pcmcia/config.opts
     to guarantee that such a large window can be found.

  ╖  The Adaptec APA-460 SlimSCSI adapter is not supported.  This card
     was originally sold under the Trantor name, and when Adaptec merged
     with Trantor, they continued to sell the Trantor card with an
     Adaptec label.  The APA-460 is not compatible with any existing
     Linux driver.


  4.5.3.  Diagnosing problems with SCSI adapters


  ╖  With the aha152x_cs driver (used by Adaptec, New Media, and a few
     others), it seems that SCSI disconnect/reconnect support is a
     frequent source of trouble with tape drives.  To disable this
     ``feature,'' add the following to /etc/pcmcia/config.opts:


       module "aha152x_cs" opts "reconnect=0"





  ╖  If you have compiled SCSI support as modules (CONFIG_SCSI is
     ``m''), when configuring PCMCIA, you must explicitly specify that
     you want the SCSI drivers to be built.  You must also modify
     /etc/pcmcia/config to load the SCSI modules before the appropriate
     *_cs driver is loaded.

  ╖  If you get ``aborting command due to timeout'' messages when the
     SCSI bus is probed, you almost certainly have an interrupt
     conflict.

  ╖  If the host driver reports ``no SCSI devices found'', verify that
     your kernel was compiled with the appropriate top-level SCSI
     drivers for your devices (i.e., disk, tape, CD-ROM, and/or
     generic).  If a top-level driver is missing, devices of that type
     will be ignored.


  4.6.  PCMCIA memory cards

  The memory_cs driver handles all types of memory cards, as well as
  providing direct access to the PCMCIA memory address space for cards
  that have other functions.  When loaded, it creates a combination of
  character and block devices.  See the man page for the module for a
  complete description of the device naming scheme.  Block devices are
  used for disk-like access (creating and mounting filesystems, etc).
  The character devices are for "raw" unbuffered reads and writes at
  arbitrary locations.

  The device address passed to memory.opts consists of two fields: the
  scheme, and the socket number.  The options are applied to the first
  common memory partition on the corresponding memory card.

  Some older memory cards, and most simple static RAM cards, lack a
  ``Card Information Structure'' (CIS), which is the scheme PCMCIA cards
  use to identify themselves.  Normally, cardmgr will assume that any
  card that lacks a CIS is a simple memory card, and load the memory_cs
  driver.  Thus, a common side effect of a general card identification
  problem is that other types of cards may be misdetected as memory
  cards.

  The memory_cs driver uses a heuristic to guess the capacity of these
  cards.  The heuristic does not work for write protected cards, and may
  make mistakes in some other cases as well.  If a card is misdetected,
  its size should then be explicitly specified when using commands such
  as dd or mkfs.


  4.6.1.  Memory device parameters


  The following parameters can be specified in memory.opts:


     DO_FSTAB
        A boolean (y/n) setting: specifies if an entry should be added
        to /etc/fstab for this device.

     DO_FSCK
        A boolean (y/n) setting: specifies if the filesystem should be
        checked before being mounted, with ``fsck -Ta''.

     DO_MOUNT
        A boolean (y/n) setting: specifies if this device should be
        automatically mounted at card insertion time.


     FSTYPE, OPTS, MOUNTPT
        The filesystem type, mount options, and mount point to be used
        for the fstab entry and/or mounting the device.

  Here is an example of a script that will automatically mount memory
  cards based on which socket they are inserted into:



       case "$ADDRESS" in
       *,0,0)
           # Mount filesystem, but don't update /etc/fstab
           DO_FSTAB="n" ; DO_FSCK="y" ; DO_MOUNT="y"
           FSTYPE="ext2" ; OPTS=""
           MOUNTPT="/mem0"
           ;;
       *,1,0)
           # Mount filesystem, but don't update /etc/fstab
           DO_FSTAB="n" ; DO_FSCK="y" ; DO_MOUNT="y"
           FSTYPE="ext2" ; OPTS=""
           MOUNTPT="/mem1"
           ;;
       esac





  4.6.2.  Using flash memory cards

  The device address passed to ftl.opts consists of three or four
  fields: the scheme, the socket number, the region number, and
  optionally, the partition number.  Most flash cards have just one
  flash memory region, so the region number will generally always be
  zero.

  To use a flash memory card as an ordinary disk-like block device,
  first create an FTL, or ``flash translation layer'', partition on the
  device with the ftl_format command.  This layer hides the device-
  specific details of flash memory programming and make the card look
  like a simple block device.  For example:



       ftl_format -i /dev/mem0c0c




  Note that this command accesses the card through the ``raw'' memory
  card interface.  Once formatted, the card can be accessed as an
  ordinary block device via the ftl_cs driver.  For example:



       mke2fs /dev/ftl0c0
       mount -t ext2 /dev/ftl0c0 /mnt




  Device naming for FTL devices is tricky.  Minor device numbers have
  three parts: the card number, the region number on that card, and
  optionally, the partition within that region.  A region can either be
  treated as a single block device with no partition table (like a
  floppy), or it can be partitioned like a hard disk device.  The
  ``ftl0c0'' device is card 0, common memory region 0, the entire
  region.  The ``ftl0c0p1'' through ``ftl0c0p4'' devices are primary
  partitions 1 through 4 if the region has been partitioned.

  There are two major formats for flash memory cards: the FTL style, and
  the Microsoft Flash File System.  The FTL format is generally more
  flexible because it allows any ordinary high-level filesystem (ext2,
  ms-dos, etc) to be used on a flash card as if it were an ordinary disk
  device.  The FFS is a completely different filesystem type.  Linux
  cannot currently handle cards formated with FFS.

  Intel Series 100 flash cards use the first 128K flash block to store
  the cards' configuration information.  To prevent accidental erasure
  of this information, ftl_format will automatically detect this and
  skip the first block when creating an FTL partition.


  4.7.  PCMCIA ATA/IDE card drives

  ATA/IDE drive support requires a 1.3.72 or higher kernel.  The PCMCIA-
  specific part of the driver is ide_cs.  Be sure to use cardctl or
  cardinfo to shut down an ATA/IDE card before ejecting it, as the
  driver has not been made ``hot-swap-proof''.

  The device addresses passed to ide.opts consist of either three or
  four fields: the current scheme, the socket number, the drive's serial
  number, and an optional partition number.  The ide_info command can be
  used to obtain an IDE device's serial number.  As with SCSI devices,
  ide.opts is first called for the entire device.  If ide.opts returns a
  list of partitions in the PARTS variable, the script will then be
  called for each partition.


  4.7.1.  ATA/IDE fixed-disk device parameters


  The following parameters can be specified in ide.opts:


     DO_FSTAB
        A boolean (y/n) setting: specifies if an entry should be added
        to /etc/fstab for this device.

     DO_FSCK
        A boolean (y/n) setting: specifies if the filesystem should be
        checked before being mounted, with ``fsck -Ta''.

     DO_MOUNT
        A boolean (y/n) setting: specifies if this device should be
        automatically mounted at card insertion time.

     FSTYPE, OPTS, MOUNTPT
        The filesystem type, mount options, and mount point to be used
        for the fstab entry and/or mounting the device.

  Here is an example ide.opts file to mount the first partition of any
  ATA/IDE card on /mnt.









  case "$ADDRESS" in
  *,*,*,1)
      DO_FSTAB="y" ; DO_FSCK="y" ; DO_MOUNT="y"
      FSTYPE="msdos"
      OPTS=""
      MOUNTPT="/mnt"
      ;;
  *,*,*)
      PARTS="1"
      ;;
  esac





  4.7.2.  Diagnosing problems with ATA/IDE adapters


  ╖  Some IDE drives violate the PCMCIA specification by requiring a
     longer time to spin up than the maximum allowed card setup time.
     To use these cards, load the pcmcia_core module with:


       CORE_OPTS="unreset_delay=400"




  ╖  To use an ATA/IDE CD-ROM device, your kernel must be compiled with
     CONFIG_BLK_DEV_IDECD enabled.  This will normally be the case for
     standard kernels, however it is something to be aware of if you
     compile a custom kernel.


  4.8.  Multifunction cards

  Starting with the 1.3.73 Linux kernel, a single interrupt can be
  shared by several drivers, such as the serial driver and an ethernet
  driver.  When using a multifunction card under a newer kernel, all
  card functions can be used without loading and unloading drivers.

  Simultaneous use of two card functions is ``tricky'' and various
  hardware vendors have implemented interrupt sharing in their own
  incompatible (and sometimes proprietary) ways.  The drivers for some
  cards (Ositech Jack of Diamonds, 3Com 3c562, Linksys) properly support
  simultaneous access, but others (Megahertz in particular) do not.

  Earlier kernels do not support interrupt sharing between different
  device drivers, so it is not possible for the PCMCIA drivers to
  configure this card for simultaneous ethernet and modem access.  The
  ethernet and serial drivers are both loaded automatically.  However,
  the ethernet driver ``owns'' the card interrupt by default.  To use
  the modem, you can unload the ethernet driver and reconfigure the
  serial port by doing something like:



       ifconfig eth0 down
       rmmod 3c589_cs
       setserial /dev/modem autoconfig auto_irq
       setserial /dev/modem




  The second setserial should verify that the port has been configured
  to use the interrupt previously used by the ethernet driver.


  5.  Advanced topics



  5.1.  Resource allocation for PCMCIA devices

  In theory, it should not really matter which interrupt is allocated to
  which device, as long as two devices are not configured to use the
  same interrupt.  In /etc/pcmcia/config.opts you'll find a place for
  excluding interrupts that are used by non-PCMCIA devices.

  Similarly, there is no way to directly specify the I/O addresses for a
  card to use.  The /etc/pcmcia/config.opts file allows you to specify
  ranges of ports available for use by any card, or to exclude ranges
  that conflict with other devices.

  After modifying /etc/pcmcia/config.opts, you can restart cardmgr with
  ``kill -HUP''.

  The interrupt used to monitor card status changes is chosen by the
  low-level socket driver module (i82365 or tcic) before cardmgr parses
  /etc/pcmcia/config, so it is not affected by changes to this file.  To
  set this interrupt, use the cs_irq= option when the socket driver is
  loaded, by setting the PCIC_OPTS variable in /etc/rc.d/rc.pcmcia.

  All the client card drivers have a parameter called irq_list for
  specifying which interrupts they may try to allocate.  These driver
  options should be set in your /etc/pcmcia/config file.  For example:



       device "serial_cs"
         module "serial_cs" opts "irq_list=8,12"
         ...




  would specify that the serial driver should only use irq 8 or irq 12.
  Regardless of irq_list settings, Card Services will never allocate an
  interrupt that is already in use by another device, or an interrupt
  that is excluded in the config file.


  5.2.  How can I have separate device setups for home and work?

  This is fairly easy using ``scheme'' support.  Use two configuration
  schemes, called ``home'' and ``work''.  Here is an example of a
  network.opts script with scheme-specific settings:













  case "$ADDRESS" in
  work,*,*,*)
      # definitions for network card in work scheme
      ...
      ;;
  home,*,*,*|default,*,*,*)
      # definitions for network card in home scheme
      ...
      ;;
  esac




  The first part of a device address is always the configuration scheme.
  In this example, the second ``case'' clause will select for both the
  ``home'' and ``default'' schemes.  So, if the scheme is unset for any
  reason, it will default to the ``home'' setup.

  Now, to select between the two sets of settings, run either:



       cardctl scheme home




  or



       cardctl scheme work




  The cardctl command does the equivalent of shutting down all your
  cards and restarting them.  The command can be safely executed whether
  or not the PCMCIA system is loaded, but the command may fail if you
  are using other PCMCIA devices at the time (even if their
  configurations are not explicitly dependant on the scheme setting).

  To find out the current scheme setting, run:



       cardctl scheme




  By default, the scheme setting is persistent across boots.  This can
  have undesirable effects if networking is initialized for the wrong
  environment.  Optionally, you can set the initial scheme value with
  the SCHEME startup option (see ``Startup options'' for details).  It
  is also possible to set the scheme from the lilo boot prompt.  Since
  lilo passes unrecognized options to init as environment variables, a
  value for SCHEME (or any other PCMCIA startup option) at the boot
  prompt will be propagated into the PCMCIA startup script.

  To save even more keystrokes, schemes can be specified in lilo's
  configuration file.  For instance, you could have:



  root = /dev/hda1
  read-only
  image = /boot/vmlinuz
    label  = home
    append = "SCHEME=home"
  image = /boot/vmlinuz
    label  = work
    append = "SCHEME=work"




  Typing ``home'' or ``work'' at the boot prompt would then boot into
  the appropriate scheme.


  5.3.  Booting from a PCMCIA device


  Having the root filesystem on a PCMCIA device is tricky because the
  Linux PCMCIA system is not designed to be linked into the kernel.  Its
  core components, the loadable kernel modules and the user mode cardmgr
  daemon, depend on an already running system.  The kernel's ``initrd''
  facility works around this requirement by allowing Linux to boot using
  a temporary ram disk as a minimal root image, load drivers, and then
  re-mount a different root filesystem.  The temporary root can
  configure PCMCIA devices and then re-mount a PCMCIA device as root.

  The initrd image absolutely must reside on a bootable device: this
  generally cannot be put on a PCMCIA device.  This is a BIOS
  limitation, not a kernel limitation.  It is useful here to distinguish
  between ``boot-able'' devices (i.e., devices that can be booted), and
  ``root-able'' devices (i.e., devices that can be mounted as root).
  ``Boot-able'' devices are determined by the BIOS, and are generally
  limited to internal floppy and hard disk drives.  ``Root-able''
  devices are any block devices that the kernel supports once it has
  been loaded.  The initrd facility makes more devices ``root-able'',
  not ``boot-able''.

  Some Linux distributions will allow installation to a device connected
  to a PCMCIA SCSI adapter, as an unintended side-effect of their
  support for installs from PCMCIA SCSI CD-ROM devices.  However, at
  present, no Linux installation tools support configuring an
  appropriate ``initrd'' to boot Linux with a PCMCIA root filesystem.
  Setting up a system with a PCMCIA root thus requires that you use
  another Linux system to create the ``initrd'' image.  If another Linux
  system is not available, another option would be to temporarily
  install a minimal Linux setup on a non-PCMCIA drive, create an initrd
  image, and then reinstall to the PCMCIA target.

  The Linux Bootdisk-HOWTO has some general information about setting up
  boot disks but nothing specific to initrd.  The main initrd document
  is included with recent kernel source code distributions, in
  linux/Documentation/initrd.txt.  Before beginning, you should read
  this document.  A familiarity with lilo is also helpful.  Using initrd
  also requires that you have a kernel compiled with CONFIG_BLK_DEV_RAM
  and CONFIG_BLK_DEV_INITRD enabled.

  This is an advanced configuration technique, and requires a high level
  of familiarity with Linux and the PCMCIA system.  Be sure to read all
  the relevant documentation before starting.  The following cookbook
  instructions should work, but deviations from the examples will
  quickly put you in uncharted and ``unsupported'' territory, and you
  will be on your own.


  This method absolutely requires that you use a PCMCIA driver release
  of 2.9.5 or later.  Older PCMCIA packages or individual components
  will not work in the initrd context.  Do not mix components from
  different releases.


  5.3.1.  The pcinitrd helper script

  The pcinitrd script creates a basic initrd image for booting with a
  PCMCIA root partition.  The image includes a minimal directory
  heirarchy, a handful of device files, a few binaries, shared
  libraries, and a set of PCMCIA driver modules.  When invoking
  pcinitrd, you specify the driver modules that you want to be included
  in the image.  The core PCMCIA components, pcmcia_core and ds, are
  automatically included.

  As an example, say that your laptop uses an i82365-compatible host
  controller, and you want to boot Linux with the root filesystem on a
  hard drive attached to an Adaptec SlimSCSI adapter.  You could create
  an appropriate initrd image with:



       pcinitrd -v initrd pcmcia/i82365.o pcmcia/aha152x_cs.o




  To customize the initrd startup sequence, you could mount the image
  using the ``loopback'' device with a command like:



       mount -o loop -t ext2 initrd /mnt




  and then edit the linuxrc script.  The configuration files will be
  installed under /etc in the image, and can also be customized.  See
  the man page for pcinitrd for more information.


  5.3.2.  Creating an initrd boot floppy


  After creating an image with pcinitrd, you can create a boot floppy by
  copying the kernel, the compressed initrd image, and a few support
  files for lilo to a clean floppy.  In the following example, we assume
  that the desired PCMCIA root device is /dev/sda1:



       mke2fs /dev/fd0
       mount /dev/fd0 /mnt
       mkdir /mnt/etc /mnt/boot /mnt/dev
       cp -a /dev/fd0 /dev/sda1 /mnt/dev
       cp [kernel-image] /mnt/vmlinuz
       gzip < [initrd-image] > /mnt/initrd




  Create /mnt/etc/lilo.conf with the contents:


       boot=/dev/fd0
       compact
       image=/vmlinuz
           label=linux
           initrd=/initrd
           read-only
           root=/dev/sda1




  Finally, invoke lilo with:



       lilo -r /mnt




  When lilo is invoked with -r, it performs all actions relative to the
  specified alternate root directory.  The reason for creating the
  device files under /mnt/dev was that lilo will not be able to use the
  files in /dev when it is running in this alternate-root mode.


  5.3.3.  Installing an initrd image on a non-Linux drive

  One common use of the initrd facility would be on systems where the
  internal hard drive is dedicated to another operating system.  The
  Linux kernel and initrd image can be placed in a non-Linux partition,
  and lilo or LOADLIN can be set up to boot Linux from these images.

  Assuming that you have a kernel has been configured for the
  appropriate root device, and an initrd image created on another
  system, the easiest way to get started is to boot Linux using LOADLIN,
  as:



       LOADLIN <kernel> initrd=<initrd-image>




  Once you can boot Linux on your target machine, you could then install
  lilo to allow booting Linux directly.  For example, say that /dev/hda1
  is the non-Linux target partition and /mnt can be used as a mount
  point.  First, create a subdirectory on the target for the Linux
  files:



       mount /dev/hda1 /mnt
       mkdir /mnt/linux
       cp [kernel-image] /mnt/linux/vmlinuz
       cp [initrd-image] /mnt/linux/initrd




  In this example, say that /dev/sda1 is the desired Linux root
  partition, a SCSI hard drive mounted via a PCMCIA SCSI adapter.  To
  install lilo, create a lilo.conf file with the contents:


       boot=/dev/hda
       map=/mnt/linux/map
       compact
       image=/mnt/linux/vmlinuz
               label=linux
               root=/dev/sda1
               initrd=/mnt/linux/initrd
               read-only
       other=/dev/hda1
               table=/dev/hda
               label=windows




  The boot= line says to install the boot loader in the master boot
  record of the specified device.  The root= line identifies the desired
  root filesystem to be used after loading the initrd image, and may be
  unnecessary if the kernel image is already configured this way.  The
  other= section is used to describe the other operating system
  installed on /dev/hda1.

  To install lilo in this case, use:



       lilo -C lilo.conf




  Note that in this case, the lilo.conf file uses absolute paths that
  include /mnt.  I did this in the example because the target filesystem
  may not support the creation of Linux device files for the boot= and
  root= options.


  6.  Dealing with unsupported cards



  6.1.  Configuring unrecognized cards


  Assuming that your card is supported by an existing driver, all that
  needs to be done is to add an entry to /etc/pcmcia/config to tell
  cardmgr how to identify the card, and which driver(s) need to be
  linked up to this card.  Check the man page for pcmcia for more
  information about the config file format.  If you insert an unknown
  card, cardmgr will normally record some identification information in
  the system log that can be used to construct the config entry.  This
  information can also be displayed with the ``cardctl ident'' command.

  Here is an example of how cardmgr will report an unsupported card in
  /usr/adm/messages.



       cardmgr[460]: unsupported card in socket 1
       cardmgr[460]: product info: "MEGAHERTZ", "XJ2288", "V.34 PCMCIA MODEM"
       cardmgr[460]: manfid: 0x0101, 0x1234  function: 2 (serial)





  The corresponding entry in /etc/pcmcia/config would be:



       card "Megahertz XJ2288 V.34 Fax Modem"
         version "MEGAHERTZ", "XJ2288", "V.34 PCMCIA MODEM"
         bind "serial_cs"




  You can use ``*'' to match strings that don't need to match exactly,
  like version numbers.  When making new config entries, be careful to
  copy the strings exactly, preserving case and blank spaces.  Also be
  sure that the config entry has the same number of strings as are
  reported in the log file.

  Beware that you can specify just about any driver for a card, but if
  you're just shooting in the dark, there is not much reason to expect
  this to be productive.  You may get lucky and find that your card is
  supported by an existing driver.  However, the most likely outcome is
  that the driver won't work, and may have unfortunate side effects like
  locking up your system.  Unlike most ordinary device drivers, which
  probe for an appropriate card, the probe for a PCMCIA device is done
  by cardmgr, and the driver itself may not do much validation before
  attempting to communicate with the device.

  After editing /etc/pcmcia/config, you can signal cardmgr to reload the
  file with:



       kill -HUP `cat /var/run/cardmgr.pid`




  If you do set up an entry for a new card, please send me a copy so
  that I can include it in the standard config file.


  6.2.  Adding support for an NE2000-compatible ethernet card

  Before you begin: this procedure will only work for simple ethernet
  cards.  Multifunction cards (i.e., ethernet/modem combo cards) have an
  extra layer of complexity regarding how the two functions are
  integrated, and generally cannot be supported without obtaining some
  configuration information from the card vendor.  Using the following
  procedure for a multifunction card will not be productive.

  First, see if the card is already recognized by cardmgr.  Some cards
  not listed in SUPPORTED.CARDS are actually OEM versions of cards that
  are supported.  If you find a card like this, let me know so I can add
  it to the list.

  If your card is not recognized, follow the instructions in the
  ``Configuring unrecognized cards'' section to create a config entry
  for your card, and bind the card to the pcnet_cs driver.  Restart
  cardmgr to use the updated config file.

  If the pcnet_cs driver says that it is unable to determine your card's
  hardware ethernet address, then edit your new config entry to bind the
  card to the memory card driver, memory_cs.  Restart cardmgr to use the
  new updated config file.  You will need to know your card's hardware
  ethernet address.  This address is a series of six two-digit hex
  numbers, often printed on the card itself.  If it is not printed on
  the card, you may be able to use a DOS driver to display the address.
  In any case, once you know it, run:



       dd if=/dev/mem0a count=20 | od -Ax -t x1




  and search the output for your address.  Only the even bytes are
  defined, so ignore the odd bytes in the dump.  Record the hex offset
  of the first byte of the address.  Now, edit modules/pcnet_cs.c and
  find the hw_info structure.  You'll need to create a new entry for
  your card.  The first field is the memory offset.  The next three
  fields are the first three bytes of the hardware address.  The final
  field contains some flags for specific card features; to start, try
  setting it to 0.

  After editing pcnet_cs.c, compile and install the new module.  Edit
  /etc/pcmcia/config again, and change the card binding from memory_cs
  to pcnet_cs.  Follow the instructions for reloading the config file,
  and you should be all set.  Please send me copies of your new hw_info
  and config entries.

  If you can't find your card's hardware address in the hex dump, as a
  method of last resort, it is possible to ``hard-wire'' the address
  when the pcnet_cs module is initialized.  Edit /etc/pcmcia/config.opts
  and add a hw_addr= option, like so:



       module "pcnet_cs" opts "hw_addr=0x00,0x80,0xc8,0x01,0x02,0x03"




  Substitute your own card's hardware address in the appropriate spot,
  of course.  Beware that if you've gotten this far, it is very unlikely
  that your card is genuinely NE2000 compatible.  In fact, I'm not sure
  if there are any cards that are not handled by one of the first two
  methods.


  6.3.  PCMCIA floppy interface cards

  The PCMCIA floppy interface used in the Compaq Aero and a few other
  laptops is not yet supported by this package.  The snag in supporting
  the Aero floppy is that the Aero seems to use a customized PCMCIA
  controller to support DMA to the floppy.  Without knowing exactly how
  this is done, there isn't any way to implement support under Linux.

  If the floppy adapter card is present when an Aero is booted, the Aero
  BIOS will configure the card, and Linux will identify it as a normal
  floppy drive.  When the Linux PCMCIA drivers are loaded, they will
  notice that the card is already configured and attached to a Linux
  driver, and this socket will be left alone.  So, the drive can be used
  if it is present at boot time, but the card is not hot swappable.


  6.4.  What's up with support for Xircom cards?

  A driver for Xircom ethernet and ethernet/modem cards is included in
  the current PCMCIA package, thanks to the work of Werner Koch.  I've
  set up a HyperNews forum specifically for discussion of Xircom driver
  development, at
  <http://hyper.stanford.edu/HyperNews/get/pcmcia/xircom.html>.

  For a long time, Xircom cards were not supported because Xircom had a
  company policy of not disclosing technical information about their
  cards.  However, they have relaxed their rules, and now, they do
  distribute driver information.


  7.  Debugging tips and programming information

  7.1.  Submitting useful bug reports

  The best way to submit bug reports is to use the HyperNews message
  lists on the Linux PCMCIA information site.  That way, other people
  can see current problems (and fixes or workarounds, if available).
  Here are some things that should be included in all bug reports:


  ╖  Your system type, and the output of the probe command.

  ╖  What PCMCIA cards you are using.

  ╖  Your Linux kernel version, and PCMCIA driver version.

  ╖  Any changes you have made to the startup files in /etc/pcmcia, or
     to the PCMCIA startup script.

  ╖  All PCMCIA-related messages in your system log file.

  All the PCMCIA modules and the cardmgr daemon send status messages to
  the system log.  This will usually be something like /var/log/messages
  or /usr/adm/messages.  This file should be the first place to look
  when tracking down a problem.  When submitting a bug report, always
  include the contents of this file.  If you are having trouble finding
  your system messages, check /etc/syslogd.conf to see how different
  classes of messages are handled.

  Before submitting a bug report, please check to make sure that you are
  using an up-to-date copy of the driver package.  While it is somewhat
  gratifying to read bug reports for things I've already fixed, it isn't
  a particularly constructive use of my time.

  If your problem involves a kernel fault, the register dump from the
  fault is only useful if you can track down the fault address, EIP.  If
  it is in the main kernel, look up the address in System.map to
  identify the function at fault.  If the fault is in a loadable module,
  it is a bit harder to trace.  With the current module tools, ``ksyms
  -m'' will report the base address of each loadable module.  Pick the
  module that contains the EIP address, and subtract its base address
  from EIP to get an offset inside that module.  Then, run gdb on that
  module, and look up the offset with the list command.  This will only
  work if you've compiled that module with -g to include debugging
  information.

  If you do not have web access, bug reports can be sent to me at
  [e-mail].  However, I prefer that bug reports be
  posted to my web site, so that they can be seen by others.


  7.2.  Low level PCMCIA debugging aids

  The PCMCIA modules contain a lot of conditionally-compiled debugging
  code.  Most of this code is under control of the PCMCIA_DEBUG
  preprocessor define.  If this is undefined, debugging code will not be
  compiled.  If set to 0, the code is compiled but inactive.  Larger
  numbers specify increasing levels of verbosity.  Each module built
  with PCMCIA_DEBUG defined will have an integer parameter, pc_debug,
  that controls the verbosity of its output.  This can be adjusted when
  the module is loaded, so output can be controlled on a per-module
  basis without recompiling.

  Your default configuration for syslogd may discard kernel debugging
  messages.  To ensure that they are recorded, edit /etc/syslog.conf to
  ensure that ``kern.debug'' messages are recorded somewhere.  See ``man
  syslog.conf'' for details.

  There are a few debugging tools in the debug_tools/ subdirectory of
  the PCMCIA distribution.  The dump_tcic and dump_i365 utilities
  generate complete register dumps of the PCMCIA controllers, and decode
  a lot of the register information.  They are most useful if you have
  access to a datasheet for the corresponding controller chip.  The
  dump_cis utility (dump_tuples in pre-3.0.2 distributions) lists the
  contents of a card's CIS (Card Information Structure), and decodes
  some of the important bits.  And the dump_cisreg utility displays a
  card's local configuration registers.

  The memory_cs memory card driver is also sometimes useful for
  debugging problems with 16-bit PC Cards.  It can be bound to any card,
  and does not interfere with other drivers.  It can be used to directly
  access any card's attribute memory or common memory.  Similarly for
  CardBus cards, the memory_cb driver can be bound to any 32-bit card,
  to give direct access to that card's address spaces.  See the man
  pages for more information.


  7.3.  /proc/bus/pccard

  Starting with 2.1.103 kernels, the PCMCIA package will create a tree
  of status information under /proc/bus/pccard.  The memory entry shows
  memory allocations for PC Card devices in a format similar to
  /proc/ioports.  Each socket also has its own subdirectory of status
  entries.  The info entry identifies the host controller and describes
  its capabilities.  The exca entry is a dump of the ``ExCA'' Intel
  i82365sl-compatible register set for that socket.  For CardBus
  bridges, the pci entry is a dump of the bridge's PCI configuration
  space, and the cardbus entry is a dump of the CardBus configuration
  registers.


  7.4.  Writing Card Services drivers for new cards

  The Linux PCMCIA Programmer's Guide is the best documentation for the
  client driver interface.  The latest version is always available from
  hyper.stanford.edu in /pub/pcmcia/doc, or on the web at
  <http://hyper.stanford.edu/HyperNews/get/pcmcia/home.html>.

  For devices that are close relatives of normal ISA devices, you will
  probably be able to use parts of existing Linux drivers.  In some
  cases, the biggest stumbling block will be modifying an existing
  driver so that it can handle adding and removing devices after boot
  time.  Of the current drivers, the memory card driver is the only
  ``self-contained'' driver that does not depend on other parts of the
  Linux kernel to do most of the dirty work.

  In many cases, the largest barrier to supporting a new card type is
  obtaining technical information from the manufacturer.  It may be
  difficult to figure out who to ask, or to explain exactly what
  information is needed.  However, with a few exceptions, it is very
  difficult if not impossible to implement a driver for a card without
  technical information from the manufacturer.


  I have written a dummy driver with lots of comments that explains a
  lot of how a driver communicates with Card Services; you will find
  this in the PCMCIA source distribution in modules/dummy_cs.c.


  7.5.  Guidelines for PCMCIA client driver authors


  I have decided that it is not really feasible for me to distribute all
  PCMCIA client drivers as part of the PCMCIA package.  Each new driver
  makes the main package incrementally harder to maintain, and including
  a driver inevitably transfers some of the maintenance work from the
  driver author to me.  Instead, I will decide on a case by case basis
  whether or not to include contributed drivers, based on user demand as
  well as maintainability.  For drivers not included in the core
  package, I suggest that driver authors adopt the following scheme for
  packaging their drivers for distribution.

  Driver files should be arranged in the same directory scheme used in
  the PCMCIA source distribution, so that the driver can be unpacked on
  top of a complete PCMCIA source tree.  A driver should include source
  files (in ./modules/), a man page (in ./man/), and configuration files
  (in ./etc/).  The top level directory should also include a README
  file.

  The top-level directory should include a makefile, set up so that
  ``make -f ... all'' and ``make -f ... install'' compile the driver and
  install all appropriate files.  If this makefile is given an extension
  of .mk, then it will automatically be invoked by the top-level
  Makefile for the all and install targets.  Here is an example of how
  such a makefile could be constructed:



       # Sample Makefile for contributed client driver
       FILES = sample_cs.mk README.sample_cs \
               modules/sample_cs.c modules/sample_cs.h \
               etc/sample etc/sample.opts man/sample_cs.4
       all:
               $(MAKE) -C modules MODULES=sample_cs.o
       install:
               $(MAKE) -C modules install-modules MODULES=sample_cs.o
               $(MAKE) -C etc install-clients CLIENTS=sample
               $(MAKE) -C man install-man4 MAN4=sample_cs.4
       dist:
               tar czvf sample_cs.tar.gz $(FILES)




  This makefile uses install targets defined in 2.9.10 and later
  versions of the PCMCIA package.  This makefile also includes a
  ``dist'' target for the convenience of the driver author.  You would
  probably want to add a version number to the final package filename
  (for example, sample_cs-1.5.tar.gz).  A complete distribution could
  look like:










  sample_cs.mk
  README.sample_cs
  modules/sample_cs.c
  modules/sample_cs.h
  etc/sample
  etc/sample.opts
  man/sample_cs.4




  With this arrangement, when the contributed driver is unpacked, it
  becomes essentially part of the PCMCIA source tree.  It can make use
  of the PCMCIA header files, as well as the machinery for checking the
  user's system configuration, and automatic dependency checking, just
  like a ``normal'' client driver.

  I will accept client drivers prepared according to this specification
  and place them in the /pub/pcmcia/contrib directory on my FTP server,
  hyper.stanford.edu.  The README in this directory will describe how to
  unpack a contributed driver.

  The client driver interface has not changed much over time, and has
  almost always preserved backwards compatibility.  A client driver will
  not normally need to be updated for minor revisions in the main
  package.  I will try to notify authors of contributed drivers of
  changes that require updates to their drivers.


  7.6.  Guidelines for Linux distribution maintainers


  If your distribution has system configuration tools that you would
  like to be PCMCIA-aware, please use the *.opts files in /etc/pcmcia
  for your ``hooks.''  These files will not be modified if a user
  compiles and installs a new release of the PCMCIA package.  If you
  modify the main configuration scripts, then a fresh install will
  silently overwrite your custom scripts and break the connection with
  your configuration tools.  Contact me if you are not sure how to write
  an appropriate option script.

  It is helpful for users (and for me) if you can document how your
  distribution deviates from the PCMCIA package as described in this
  document.  In particular, please document changes to the startup
  script and configuration scripts.  If you send me the appropriate
  information, I will include it in the ``Notes about specific Linux
  distributions''.

  When building PCMCIA for distribution, consider including contributed
  drivers that are not part of the main PCMCIA package.  For reasons of
  maintainability, I am trying to limit the core package size, by only
  adding new drivers if I think they are of particularly broad interest.
  Other drivers will be distributed separately, as described in the
  previous section.  The split between integral and separate drivers is
  somewhat arbitrary and partly historical, and should not imply a
  difference in quality.