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Edit for clarity and readability. Fix title capitalization.

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en_US.ISO8859-1/books/arch-handbook/pccard/chapter.sgml
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@ -12,22 +12,24 @@
<para>This chapter will talk about the FreeBSD mechanisms for
writing a device driver for a PC Card or CardBus device. However,
at the present time, it just documents how to add a driver to an
at present it just documents how to add a new device to an
existing pccard driver.</para>
<sect1 id="pccard-adddev">
<title>Adding a device</title>
<title>Adding a Device</title>
<para>Devices drivers know what devices they
support. There is a table of supported devices in the
kernel that drivers use to attach to a device.</para>
<para>Device drivers know what devices they support. There is a
table of supported devices in the kernel that drivers use to
attach to a device.</para>
<sect2 id="pccard-overview">
<title>Overview</title>
<indexterm><primary>CIS</primary></indexterm>
<para>PC Cards are identified in one of two ways, both based on
information in the <acronym>CIS</acronym> of the card. The
the <firstterm>Card Information Structure</firstterm>
(<acronym role="Card Information Structure">CIS</acronym>)
stored on the card. The
first method is to use numeric manufacturer and product
numbers. The second method is to use the human readable
strings that are also contained in the CIS. The PC Card bus
@ -35,34 +37,33 @@
design pattern to help the driver writer match devices to his
driver.</para>
<para>OEMs manufacturers often develop a reference design for
a PC Card product sell this design to other companies to
market. Those companies refine
the design, market the product to their target audience or
geographic area and put their own name plate onto the card.
The refinements to the physical card typically are
very minor, if any changes are made at all. However,
to strengthen their brand,
these vendors place their company name in the human
strings in the CIS space, but leave the manufacturer and
product ids unchanged.</para>
<para>Original equipment manufacturers (<acronym>OEM</acronym>s)
often develop a
reference design for a PC Card product, then sell this design
to other companies to market. Those companies refine the
design, market the product to their target audience or
geographic area, and put their own name plate onto the card.
The refinements to the physical card are typically very minor,
if any changes are made at all. To strengthen their brand,
these vendors place their company name in the human readable strings in
the CIS space, but leave the manufacturer and product IDs
unchanged.</para>
<indexterm><primary>NetGear</primary></indexterm>
<indexterm><primary>Linksys</primary></indexterm>
<indexterm><primary>D-Link</primary></indexterm>
<para>Because of this practice, FreeBSD drivers tend to
use the numeric IDs. Using numeric IDs and a centralized
database complicates adding IDs and support for cards to the
system. One must carefully check to see who really made the
card, especially when it appears that the vendor who made the
card from might already have a different manufacturer id
listed in the central database. Linksys, D-Link and NetGear
are a number of US Manufacturers of LAN hardware that often
sell the same design. These same designs can be sold in Japan
under names such as Buffalo and Corega. Yet often, these
devices will all have the same manufacturer and product
id.</para>
<para>Because of this practice, FreeBSD drivers usually rely on
numeric IDs for device identification. Using numeric IDs and a centralized database
complicates adding IDs and support for cards to the system.
One must carefully check to see who really made the card,
especially when it appears that the vendor who made the card
might already have a different manufacturer ID listed in the
central database. Linksys, D-Link, and NetGear are a number of
US manufacturers of LAN hardware that often sell the same
design. These same designs can be sold in Japan under names
such as Buffalo and Corega. Often, these devices will all
have the same manufacturer and product IDs.</para>
<para>The PC Card bus code keeps a central database of card
information, but not which driver is associated with them, in
@ -72,11 +73,11 @@
devices.</para>
<para>Finally, some really low end devices do not contain
manufacturer identification at all. These devices require
that one matches them using the human readable CIS strings.
manufacturer identification at all. These devices must be
detected by matching the human readable CIS strings.
While it would be nice if we did not need this method as a
fallback, it is necessary for some very low end CD-ROM players
and ethernet cards. This method should generally be
and Ethernet cards. This method should generally be
avoided, but a number of devices are listed in this section
because they were added prior to the recognition of the
<acronym>OEM</acronym> nature of the PC Card business. When
@ -86,51 +87,54 @@
<sect2 id="pccard-pccarddevs">
<title>Format of <filename>pccarddevs</filename></title>
<para>There are four sections of the
<para>There are four sections in the
<filename>pccarddevs</filename> files. The first section
lists the manufacturer numbers for those vendors that use
lists the manufacturer numbers for vendors that use
them. This section is sorted in numerical order. The next
section has all of the products that are used by these
vendors, along with their product ID numbers and a description
string. The description string typically is not used (instead
we set the device's description based on the human readable
CIS, even if we match on the numeric version). These two
sections are then repeated for those devices that use the
string matching method. Finally, C-style comments are allowed
anywhere in the file.</para>
sections are then repeated for devices that use the
string matching method. Finally, C-style comments enclosed in
<literal>/*</literal> and <literal>*/</literal> characters are
allowed anywhere in the file.</para>
<para>The first section of the file contains the vendor IDs.
Please keep this list sorted in numeric order. Also, please
coordinate changes to this file because we share it with
NetBSD to help facilitate a common clearing house for this
information. For example:</para>
information. For example, here are the first few vendor
IDs:</para>
<programlisting>vendor FUJITSU 0x0004 Fujitsu Corporation
vendor NETGEAR_2 0x000b Netgear
vendor PANASONIC 0x0032 Matsushita Electric Industrial Co.
vendor SANDISK 0x0045 Sandisk Corporation</programlisting>
<para>shows the first few vendor ids. Chances are very good
<para>Chances are very good
that the <literal>NETGEAR_2</literal> entry is really an OEM
that NETGEAR purchased cards from and the author of support
for those cards was unaware at the time that Netgear was using
someone else's id. These entries are fairly straightforward.
There is the vendor keyword used to denote the kind of line
that this is. There is the name of the vendor. This name
will be repeated later in the pccarddevs file, as well as used
in the driver's match tables, so keep it short and a valid C
identifier. There is a numeric ID, in hex, for the
someone else's ID. These entries are fairly straightforward.
The vendor keyword denotes the kind of line that this is,
followed by the name of the vendor. This name will be
repeated later in <filename>pccarddevs</filename>, as
well as used in the driver's match tables, so keep it short
and a valid C identifier. A numeric ID in hex identifies the
manufacturer. Do not add IDs of the form
<literal>0xffffffff</literal> or <literal>0xffff</literal>
because these are reserved ids (the former is 'no id set'
while the latter is sometimes seen in extremely poor quality
cards to try to indicate 'none). Finally there is a string
description of the company that makes the card. This string
is not used in FreeBSD for anything but commentary
purposes.</para>
because these are reserved IDs (the former is
<quote>no ID set</quote> while the latter is sometimes seen in
extremely poor quality cards to try to indicate
<quote>none</quote>). Finally there is a string description
of the company that makes the card. This string is not used
in FreeBSD for anything but commentary purposes.</para>
<para>The second section of the file contains the products. As
you can see in the following example:</para>
shown in this example, the format is similar to the vendor
lines:</para>
<programlisting>/* Allied Telesis K.K. */
product ALLIEDTELESIS LA_PCM 0x0002 Allied Telesis LA-PCM
@ -138,12 +142,12 @@ product ALLIEDTELESIS LA_PCM 0x0002 Allied Telesis LA-PCM
/* Archos */
product ARCHOS ARC_ATAPI 0x0043 MiniCD</programlisting>
<para>the format is similar to the vendor lines. There is the
product keyword. Then there is the vendor name, repeated from
above. This is followed by the product name, which is used by
the driver and should be a valid C identifier, but may also
start with a number. There is then the product id for this
card, in hex. As with the vendors, there is the same
<para>The
<literal>product</literal> keyword is followed by the vendor
name, repeated from above. This is followed by the product
name, which is used by the driver and should be a valid C
identifier, but may also start with a number. As with the
vendors, the hex product ID for this card follows the same
convention for <literal>0xffffffff</literal> and
<literal>0xffff</literal>. Finally, there is a string
description of the device itself. This string typically is
@ -151,51 +155,51 @@ product ARCHOS ARC_ATAPI 0x0043 MiniCD</programlisting>
construct a string from the human readable CIS entries, but it
can be used in the rare cases where this is somehow
insufficient. The products are in alphabetical order by
manufacturer, then numerical order by product id. They have a
manufacturer, then numerical order by product ID. They have a
C comment before each manufacturer's entries and there is a
blank line between entries.</para>
<para>The third section is like the previous vendor section, but
with all of the manufacturer numeric ids as
<literal>-1</literal>. <literal>-1</literal> means
<quote>match anything you find</quote> in the FreeBSD pccard
with all of the manufacturer numeric IDs set to
<literal>-1</literal>, meaning
<quote>match anything found</quote> in the FreeBSD pccard
bus code. Since these are C identifiers, their names must be
unique. Otherwise the format is identical to the first
section of the file.</para>
<para>The final section contains the entries for those cards
that we must match with string entries. This sections' format
is a little different than the generic section:</para>
that must be identified by string entries. This section's format
is a little different from the generic section:</para>
<programlisting>product ADDTRON AWP100 { "Addtron", "AWP-100&amp;spWireless&amp;spPCMCIA", "Version&amp;sp01.02", NULL }
product ALLIEDTELESIS WR211PCM { "Allied&amp;spTelesis&amp;spK.K.", "WR211PCM", NULL, NULL } Allied Telesis WR211PCM</programlisting>
<para>We have the familiar product keyword, followed by the
vendor name followed by the card name, just as in the second
section of the file. However, then we deviate from that
format. There is a {} grouping, followed by a number of
strings. These strings correspond to the vendor, product and
<para>The familiar <literal>product</literal> keyword is
followed by the vendor name and the card name, just as in the
second section of the file. Here the format deviates from
that used earlier. There is a {} grouping, followed by a number of
strings. These strings correspond to the vendor, product, and
extra information that is defined in a CIS_INFO tuple. These
strings are filtered by the program that generates
<filename>pccarddevs.h</filename> to replace &amp;sp with a
real space. NULL strings mean that the corresponding part
of the entry should be ignored. In the example I have picked,
there is a bad entry. It should not contain the version
number in it unless that is critical for the operation of the
card. Sometimes vendors will have many different versions of
the card in the field that all work, in which case that
information only makes it harder for someone with a similar
card to use it with FreeBSD. Sometimes it is necessary when a
vendor wishes to sell many different parts under the same
brand due to market considerations (availability, price, and
so forth). Then it can be critical to disambiguating the card
in those rare cases where the vendor kept the same
manufacturer/product pair. Regular expression matching is not
available at this time.</para>
real space. NULL strings mean that the corresponding part of
the entry should be ignored. The example shown here contains
a bad entry. It should not contain the version number unless
that is critical for the operation of the card. Sometimes
vendors will have many different versions of the card in the
field that all work, in which case that information only makes
it harder for someone with a similar card to use it with
FreeBSD. Sometimes it is necessary when a vendor wishes to
sell many different parts under the same brand due to market
considerations (availability, price, and so forth). Then it
can be critical to disambiguating the card in those rare cases
where the vendor kept the same manufacturer/product pair.
Regular expression matching is not available at this
time.</para>
</sect2>
<sect2 id="pccard-probe">
<title>Sample probe routine</title>
<title>Sample Probe Routine</title>
<indexterm>
<primary>PC Card</primary>
@ -241,9 +245,10 @@ wi_pccard_probe(dev)
first entry that it matches. Some drivers may use this
mechanism to convey additional information about some cards to
the rest of the driver, so there may be some variance in the
table. The only requirement is that if you have a different
table, the first element of the structure you have a table of
be a struct pccard_product.</para>
table. The only requirement is that each row of the table
must have a <function>struct</function>
<structname>pccard_product</structname> as the first
element.</para>
<para>Looking at the table
<structname>wi_pccard_products</structname>, one notices that
@ -251,41 +256,41 @@ wi_pccard_probe(dev)
<function>PCMCIA_CARD(<replaceable>foo</replaceable>,
<replaceable>bar</replaceable>,
<replaceable>baz</replaceable>)</function>. The
<replaceable>foo</replaceable> part is the manufacturer id
<replaceable>foo</replaceable> part is the manufacturer ID
from <filename>pccarddevs</filename>. The
<replaceable>bar</replaceable> part is the product. The
<replaceable>bar</replaceable> part is the product ID.
<replaceable>baz</replaceable> is the expected function number
that for this card. Many pccards can have multiple functions,
for this card. Many pccards can have multiple functions,
and some way to disambiguate function 1 from function 0 is
needed. You may see <literal>PCMCIA_CARD_D</literal>, which
includes the device description from the
<filename>pccarddevs</filename> file. You may also see
includes the device description from
<filename>pccarddevs</filename>. You may also see
<literal>PCMCIA_CARD2</literal> and
<literal>PCMCIA_CARD2_D</literal> which are used when you need
to match CIS both CIS strings and manufacturer numbers, in the
to match both CIS strings and manufacturer numbers, in the
<quote>use the default description</quote> and <quote>take the
description from pccarddevs</quote> flavors.</para>
</sect2>
<sect2 id="pccard-add">
<title>Putting it all together</title>
<title>Putting it All Together</title>
<para>So, to add a new device, one must do the following steps.
First, one must obtain the identification information from the
<para>To add a new device, one must first obtain the
identification information from the
device. The easiest way to do this is to insert the device
into a PC Card or CF slot and issue
<command>devinfo -v</command>. You will likely see something
like:</para>
<command>devinfo -v</command>. Sample output:</para>
<programlisting> cbb1 pnpinfo vendor=0x104c device=0xac51 subvendor=0x1265 subdevice=0x0300 class=0x060700 at slot=10 function=1
cardbus1
pccard1
unknown pnpinfo manufacturer=0x026f product=0x030c cisvendor="BUFFALO" cisproduct="WLI2-CF-S11" function_type=6 at function=0</programlisting>
<para>as part of the output. The manufacturer and product are
the numeric IDs for this product. While the cisvendor and
cisproduct are the strings that are present in the CIS that
describe this product.</para>
<para><literal>manufacturer</literal>
and <literal>product</literal> are the numeric IDs for this
product, while <literal>cisvendor</literal> and
<literal>cisproduct</literal> are the product description
strings from the CIS.</para>
<para>Since we first want to prefer the numeric option, first
try to construct an entry based on that. The above card has
@ -295,8 +300,8 @@ wi_pccard_probe(dev)
<programlisting>vendor BUFFALO 0x026f BUFFALO (Melco Corporation)</programlisting>
<para>so we are good there. Looking for an entry for this card,
we do not find one. Instead we find:</para>
<para>But there is no entry for this particular card.
Instead we find:</para>
<programlisting>/* BUFFALO */
product BUFFALO WLI_PCM_S11 0x0305 BUFFALO AirStation 11Mbps WLAN
@ -304,21 +309,20 @@ product BUFFALO LPC_CF_CLT 0x0307 BUFFALO LPC-CF-CLT
product BUFFALO LPC3_CLT 0x030a BUFFALO LPC3-CLT Ethernet Adapter
product BUFFALO WLI_CF_S11G 0x030b BUFFALO AirStation 11Mbps CF WLAN</programlisting>
<para>we can just add</para>
<para>To add the device, we can just add this entry to <filename>pccarddevs</filename>:</para>
<programlisting>product BUFFALO WLI2_CF_S11G 0x030c BUFFALO AirStation ultra 802.11b CF</programlisting>
<para>to <filename>pccarddevs</filename>. Presently, there is a
manual step to regenerate the
<filename>pccarddevs.h</filename> file used to convey these
identifiers to the client driver. The following steps
must be done before you can use them in the driver:</para>
<para>At present, there is a
manual step to regenerate
<filename>pccarddevs.h</filename>, used to convey these
identifiers to the client driver. The following steps must be
done before you can use them in the driver:</para>
<screen>&prompt.root; <userinput>cd src/sys/dev/pccard</userinput>
&prompt.root; <userinput>make -f Makefile.pccarddevs</userinput>
</screen>
&prompt.root; <userinput>make -f Makefile.pccarddevs</userinput></screen>
<para>Once these steps are complete, you can add the card to the
<para>Once these steps are complete, the card can be added to the
driver. That is a simple operation of adding one line:</para>
<programlisting>static const struct pccard_product wi_pccard_products[] = {
@ -334,31 +338,30 @@ product BUFFALO WLI_CF_S11G 0x030b BUFFALO AirStation 11Mbps CF WLAN</programlis
line before the line that I added, but that is simply to
highlight the line. Do not add it to the actual driver. Once
you have added the line, you can recompile your kernel or
module and try to see if it recognizes the device. If it does
module and test it. If the device is recognized
and works, please submit a patch. If it does not work, please
figure out what is needed to make it work and submit a patch.
If it did not recognize it at all, you have done something
If the device is not recognized at all, you have done something
wrong and should recheck each step.</para>
<para>If you are a FreeBSD src committer, and everything appears
to be working, then you can commit the changes to the tree.
However, there are some minor tricky things that you need to
worry about. First, you must commit the
<filename>pccarddevs</filename> file to the tree. After you
have done that, you must regenerate
<filename>pccarddevs.h</filename> and commit it as a second
commit (this is to make sure that the right
&dollar;FreeBSD&dollar; tag is in the latter file). Finally,
you need to commit the additions to the driver.</para>
However, there are some minor tricky things to be considered.
<filename>pccarddevs</filename> must be committed to the tree first.
Then <filename>pccarddevs.h</filename> must be regenerated
and committed as a second
step, ensuring that the right
&dollar;FreeBSD&dollar; tag is in the latter file. Finally,
commit the additions to the driver.</para>
</sect2>
<sect2 id="pccard-pr">
<title>Submitting a new device</title>
<title>Submitting a New Device</title>
<para>Many people send entries for new devices to the author
directly. Please do not do this. Please submit them as a PR
and send the author the PR number for his records. This makes
sure that entries are not lost. When submitting a PR, it is
<para>Please do not send entries for new devices to the author
directly. Instead, submit them as a PR
and send the author the PR number for his records. This
ensures that entries are not lost. When submitting a PR, it is
unnecessary to include the <filename>pccardevs.h</filename>
diffs in the patch, since those will be regenerated. It is
necessary to include a description of the device, as well as