From 849369d6c66d3054688672f97d31fceb8e8230fb Mon Sep 17 00:00:00 2001 From: root Date: Fri, 25 Dec 2015 04:40:36 +0000 Subject: initial_commit --- Documentation/pcmcia/devicetable.txt | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) create mode 100644 Documentation/pcmcia/devicetable.txt (limited to 'Documentation/pcmcia/devicetable.txt') diff --git a/Documentation/pcmcia/devicetable.txt b/Documentation/pcmcia/devicetable.txt new file mode 100644 index 00000000..199afd10 --- /dev/null +++ b/Documentation/pcmcia/devicetable.txt @@ -0,0 +1,33 @@ +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 catting the file +"modalias" in the sysfs directory of the PCMCIA device. It generates a string +in the following form: +pcmcia:m0149cC1ABf06pfn00fn00pa725B842DpbF1EFEE84pc0877B627pd00000000 + +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 crc32hash (see Documentation/pcmcia/crc32hash.c) +to determine the crc32 hash. Simply pass the string you want to evaluate +as argument to this program, e.g.: +$ ./crc32hash "Dual Speed" -- cgit v1.2.3