Great, thanks for the info guys.
>
>
> Check out the man page for mmap on a "full" linux system or on the web.
> mmap can only be used to map to a page boundary. You then add suitable
> offsets, depending on usage, to this mmap'ed base pointer.
>
> check out the ts7200io.c file in my adio program at
>
> http://www.comp.leeds.ac.uk/jj/linux/adio.tgz
> <http://www.comp.leeds.ac.uk/jj/linux/adio.tgz>
>
> This app note describes how this sort of stuff is done...
>
> http://www.simtec.co.uk/appnotes/AN0014/
> <http://www.simtec.co.uk/appnotes/AN0014/>
>
> Jim
> ----------------------------------------------------------
> HomePage: http://www.comp.leeds.ac.uk/jj <http://www.comp.leeds.ac.uk/jj>
> TS7200 Page: http://www.comp.leeds.ac.uk/jj/linux/arm-sbc.html
> <http://www.comp.leeds.ac.uk/jj/linux/arm-sbc.html>
>
> On Fri, 6 Feb 2009, sean machin wrote:
>
> > Hi All,
> >
> > I'm writing a driver which needs to interface to the digital I/O ports
> > on my TS-7260. The particular physical addresses
> > I need access to are 0x80840014 for a data direction register and
> > 0x80840004 for the data register.
> >
> > It looks like my call to mmap the address 0x80840014 is failing with
> > errno 22 (invalid argument). Anyone on the
> > list got an idea why the call is failing? Thanks.
> >
> > ----------------------------------------------------------
> > uint8_t* ddr_reg = mmap(0, getpagesize(), PROT_READ|PROT_WRITE,
> > MAP_SHARED, fd, 0x80840014);
> > if (ddr_reg == MAP_FAILED) {
> > syslog(LOG_ERR, "mmap failed with errno %d", errno);
> > }
> >
> >
>
>
------------------------------------
Yahoo! Groups Links
<*> To visit your group on the web, go to:
http://groups.yahoo.com/group/ts-7000/
<*> Your email settings:
Individual Email | Traditional
<*> To change settings online go to:
http://groups.yahoo.com/group/ts-7000/join
(Yahoo! ID required)
<*> To change settings via email:
<*> To unsubscribe from this group, send an email to:
<*> Your use of Yahoo! Groups is subject to:
http://docs.yahoo.com/info/terms/
|