Date: Mon, 18 Oct 2004 23:16:06 -0600 (MDT) From: "M. Warner Losh" <imp@bsdimp.com> To: listmember@thiemo.net Cc: freebsd-hackers@freebsd.org Subject: Re: How to access a device on LPC bus? Message-ID: <20041018.231606.33009893.imp@bsdimp.com> In-Reply-To: <20041017115011.GA22744@mygiea.ham01.thiemo.net> References: <20041017115011.GA22744@mygiea.ham01.thiemo.net>
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In message: <20041017115011.GA22744@mygiea.ham01.thiemo.net>
Thiemo Nordenholz <listmember@thiemo.net> writes:
: 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?
If there's a HID, you don't need an identify routine. Just match the
pnp id. You can have ISA and/or ACPI attachments to cover both cases.
Warner
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