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"

or using the more compact product ID codes:

card "Megahertz XJ2288 V.34 Fax Modem"
  manfid 0x0101, 0x1234
  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 clients/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.