Writing a driver for a card reader controller - how?

M. Warner Losh imp at bsdimp.com
Mon Nov 28 17:14:40 GMT 2005

In message: <200511281115.28735.jhb at freebsd.org>
            John Baldwin <jhb at freebsd.org> writes:
: On Thursday 24 November 2005 01:26 pm, M. Warner Losh wrote:
: > In message: <20051124111241.GB75190 at mygiea.ham01.thiemo.net>
: >
: >             Thiemo Nordenholz <listmember at thiemo.net> writes:
: > : Hi Warner,
: > :
: > : > to be set.  Can you send me a pointer to the winbond datasheet you are
: > : > using?  IIRC, this chip has an odd API since it appears to be derived
: > :
: > : As I have to wait for some spare time before trying to use the hints I
: > : have received here, for now I can only answer that question - I found a
: > : datasheet at
: > : http://www.winbond.com/e-winbondhtm/partner/PDFresult.asp?Pname=863 which
: > : is what I try to work with. (That page sends a file "PDFresult.asp",
: > : which is actually a PDF.)
: >
: > I've read through this pdf.  As far as I can find, it just talks about
: > how to setup the base address for each of the sets of registers
: > without actually talking about the sets of registers themselves.  Nor
: > can I find in the document a pointer to the different register sets.
: > Do you have one of those as well?  It looks fairly easy to program
: > this device's base addresses or inquire what they are.  It is done in
: > much the same way that super I/O chips are programmed.
: For an ACPI device you want to use _PRS and _SRS.  _PRS will give you a list 
: of candidate resource sets, possibly in groups via DPF tags.  You then build 
: a resource and do an _SRS to set it.  The problem is that our ACPI bus isn't 
: smart enough to allocate resources for a device when bus_alloc_resource() is 
: called to choose available resources when a device is not configured.  This 
: is similar to how you fixed the PCI bus recently to allocate resources for 
: BARs that weren't already allocated by the BIOS.

Ah, I see.  Sounds like time to jump into the ACPI code and do
someting similar...


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