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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 ( ).

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 3.1, and minor updates or bug fixes are numbered 3.1.1, 3.1.2, and so on.

Source code for the latest version is available on the web at http://pcmcia-cs.sourceforge.net, as pcmcia-cs-3.1.?.tar.gz. You may find more than one release number here. It is up to you to decide which version is more appropriate, but the CHANGES file will summarize the most important differences.

The Linux PCMCIA FTP site 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:

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.

Support for Toshiba's ToPIC bridges was hindered for a long time by a lack of sufficiently detailed technical documentation. While some datasheets have been available, a few idiosyncracies of the ToPIC chips were not adequately explained. Toshiba has now started giving direct technical help on some of these issues and I expect that the major ones will soon be resolved.

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 favorite (unsupported) card become 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://pcmcia-cs.sourceforge.net. 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 majordomo@vger.rutgers.edu. 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.


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