How to access a device on LPC bus?

From: Thiemo Nordenholz (listmember_at_thiemo.net)
Date: 10/17/04

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    Date: Sun, 17 Oct 2004 13:50:11 +0200
To: freebsd-hackers@freebsd.org

    Hi there,

    beginner's question, maybe: How do I, from a device driver point of view,
    access a device attached to the "Low Pincount" (LPC) bus?

    I have a Winbond W83L518D card reader controller in a notebook that I want
    to access. The only way I see this device at all is (on 5.3-BETA7) in
    "pnpinfo -v" output, where it shows up as

        unknown pnpinfo _HID=WEC0518 _UID=0 at handle=\_SB_.C046.C059.C140

    -- I have identified it then by the Hardware ID. I do not see any more
    information, especially no resource usage.

    As far as I have read, the LPC bus devices can accessed just like ISA
    devices. Actually, what seems to be the ACPI parent of this Winbond chip
    (with handle \_SB_.C046.C059) is shown as isab0 in the devinfo output.

    Now, to implement an identify function in a driver for this, I need to
    access data in the controller - but I don't have any information about its
    memory attachments...
    Could anyone give me a hint what to do here, some driver to look into for an
    example, or just tell me that my idea of an ISA driver on fBSD is completely
    wrong?

    Thanks in advance,
      Thiemo 

    -- 
Query a PGP key server (e.g. http://www.pgp.net/) for my public key 41068629.

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