Commit 5085cb26 authored by Dominik Brodowski's avatar Dominik Brodowski Committed by Linus Torvalds

[PATCH] pcmcia: add some Documentation

Add some information useful for PCMCIA device driver authors to
Documentation/pcmcia/, and reference it in dmesg in case of hash mismatches.

Also add a reference to pcmciautils to Documentation/Changes.  With recent
changes, you don't need to concern yourself with pcmcia-cs even if you have
PCMCIA hardware, so the example above the list needed to be adapted as well.
Signed-off-by: default avatarDominik Brodowski <>
Signed-off-by: default avatarAndrew Morton <>
Signed-off-by: default avatarLinus Torvalds <>
parent f4d7510d
......@@ -44,9 +44,9 @@ running, the suggested command should tell you.
Again, keep in mind that this list assumes you are already
functionally running a Linux 2.4 kernel. Also, not all tools are
necessary on all systems; obviously, if you don't have any PCMCIA (PC
Card) hardware, for example, you probably needn't concern yourself
with pcmcia-cs.
necessary on all systems; obviously, if you don't have any ISDN
hardware, for example, you probably needn't concern yourself with
o Gnu C 2.95.3 # gcc --version
o Gnu make 3.79.1 # make --version
......@@ -57,6 +57,7 @@ o e2fsprogs 1.29 # tune2fs
o jfsutils 1.1.3 # fsck.jfs -V
o reiserfsprogs 3.6.3 # reiserfsck -V 2>&1|grep reiserfsprogs
o xfsprogs 2.6.0 # xfs_db -V
o pcmciautils 001
o pcmcia-cs 3.1.21 # cardmgr -V
o quota-tools 3.09 # quota -V
o PPP 2.4.0 # pppd --version
......@@ -186,13 +187,20 @@ architecture independent and any version from 2.0.0 onward should
work correctly with this version of the XFS kernel code (2.6.0 or
later is recommended, due to some significant improvements).
PCMCIAutils replaces pcmcia-cs (see below). It properly sets up
PCMCIA sockets at system startup and loads the appropriate modules
for 16-bit PCMCIA devices if the kernel is modularized and the hotplug
subsystem is used.
PCMCIA (PC Card) support is now partially implemented in the main
kernel source. Pay attention when you recompile your kernel ;-).
Also, be sure to upgrade to the latest pcmcia-cs release.
kernel source. The "pcmciautils" package (see above) replaces pcmcia-cs
for newest kernels.
......@@ -349,9 +357,13 @@ Xfsprogs
o <>
o <>
o <>
o <>
Matching of PCMCIA devices to drivers is done using one or more of the
following criteria:
- manufactor ID
- card ID
- product ID strings _and_ hashes of these strings
- function ID
- device function (actual and pseudo)
You should use the helpers in include/pcmcia/device_id.h for generating the
struct pcmcia_device_id[] entries which match devices to drivers.
If you want to match product ID strings, you also need to pass the crc32
hashes of the string to the macro, e.g. if you want to match the product ID
string 1, you need to use
PCMCIA_DEVICE_PROD_ID1("some_string", 0x(hash_of_some_string)),
If the hash is incorrect, the kernel will inform you about this in "dmesg"
upon module initialization, and tell you of the correct hash.
You can determine the hash of the product ID strings by running
"pcmcia-modalias %n.%m" [%n being replaced with the socket number and %m being
replaced with the device function] from pcmciautils. It generates a string
in the following form:
The hex value after "pa" is the hash of product ID string 1, after "pb" for
string 2 and so on.
Alternatively, you can use this small tool to determine the crc32 hash.
simply pass the string you want to evaluate as argument to this program,
$ ./crc32hash "Dual Speed"
/* crc32hash.c - derived from linux/lib/crc32.c, GNU GPL v2 */
#include <string.h>
#include <stdio.h>
#include <ctype.h>
#include <stdlib.h>
unsigned int crc32(unsigned char const *p, unsigned int len)
int i;
unsigned int crc = 0;
while (len--)
crc ^= *p++;
for (i = 0; i < 8; i++)
crc = (crc >> 1) ^ ((crc & 1) ? 0xedb88320 : 0);
return crc;
int main(int argc, char **argv) {
unsigned int result;
if (argc != 2) {
printf("no string passed as argument\n");
return -1;
result = crc32(argv[1], strlen(argv[1]));
printf("0x%x\n", result);
return 0;
This file details changes in 2.6 which affect PCMCIA card driver authors:
* in-kernel device<->driver matching
PCMCIA devices and their correct drivers can now be matched in
kernelspace. See 'devicetable.txt' for details.
* Device model integration (as of 2.6.11)
A struct pcmcia_device is registered with the device model core,
and can be used (e.g. for SET_NETDEV_DEV) by using
handle_to_dev(client_handle_t * handle).
* Convert internal I/O port addresses to unsigned long (as of 2.6.11)
ioaddr_t should be replaced by kio_addr_t in PCMCIA card drivers.
* irq_mask and irq_list parameters (as of 2.6.11)
The irq_mask and irq_list parameters should no longer be used in
PCMCIA card drivers. Instead, it is the job of the PCMCIA core to
determine which IRQ should be used. Therefore, link->irq.IRQInfo2
is ignored.
* client->PendingEvents is gone (as of 2.6.11)
client->PendingEvents is no longer available.
* client->Attributes are gone (as of 2.6.11)
client->Attributes is unused, therefore it is removed from all
PCMCIA card drivers
* core functions no longer available (as of 2.6.11)
The following functions have been removed from the kernel source
because they are unused by all in-kernel drivers, and no external
driver was reported to rely on them:
* device list iteration upon module removal (as of 2.6.10)
It is no longer necessary to iterate on the driver's internal
client list and call the ->detach() function upon module removal.
* Resource management. (as of 2.6.8)
Although the PCMCIA subsystem will allocate resources for cards,
it no longer marks these resources busy. This means that driver
authors are now responsible for claiming your resources as per
other drivers in Linux. You should use request_region() to mark
your IO regions in-use, and request_mem_region() to mark your
memory regions in-use. The name argument should be a pointer to
your driver name. Eg, for pcnet_cs, name should point to the
string "pcnet_cs".
......@@ -262,8 +262,6 @@ void cs_error(client_handle_t handle, int func, int ret)
static void pcmcia_check_driver(struct pcmcia_driver *p_drv)
......@@ -284,6 +282,9 @@ static void pcmcia_check_driver(struct pcmcia_driver *p_drv)
"product string \"%s\": is 0x%x, should "
"be 0x%x\n", p_drv->, did->prod_id[i],
did->prod_id_hash[i], hash);
printk(KERN_DEBUG "pcmcia: see "
"Documentation/pcmcia/devicetable.txt for "
......@@ -291,12 +292,6 @@ static void pcmcia_check_driver(struct pcmcia_driver *p_drv)
static inline void pcmcia_check_driver(struct pcmcia_driver *p_drv) {
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