Re: uio_pci_generic driver

["Hans J. Koch" <hjk@hansjkoch.de>]

On Tue, Mar 20, 2012 at 10:48:25PM +0400, tochansky@tochlab.net wrote:
> > On Tue, Mar 20, 2012 at 09:56:03PM +0400, tochansky@tochlab.net wrote:
> >> Hello!
> >> I have a question about uio_pci_generic driver. I'm trying to use it in
> >> my
> >> project, but have no luck.
> >> There are very little information on the subject. If you have a few
> >> minutes, I would like to ask a few questions.
> >> I need to mmap() memory of my board to work with it. I did
> >> # modprobe uio_pci_generic
> >> # echo "xxxx xxxx" > /sys/bus/pci/drivers/uio_pci_generic/new_id
> >>
> >> Files in /sys/class/uio/uio0 appears, but there no directory named
> >> /sys/class/uio/uio0/maps/.
> >> Anyway I tryed to mmap with code:
> >>
> >> #include <sys/types.h>
> >> #include <sys/stat.h>
> >> #include <fcntl.h>
> >>
> >> #include <sys/mman.h>
> >> #include <stdio.h>
> >>
> >> int main()
> >> {
> >>         int fd = open("/dev/uio0", O_RDWR | O_SYNC);
> >>         printf("fd = %d\n", fd);
> >>         void *addr = mmap(NULL, 1024, PROT_READ, MAP_SHARED, fd, 0);
> >>         printf("addr = %p\n", addr);
> >> }
> >>
> >> Ofcourse, mmap() failes with error "Invalid argument". Nothing criminal
> >> in
> >> dmesg and any other hints of error.
> >>
> >> --
> >> Dmitriy
> >
> >
> > Map memory through /sys/bus/pci/devices/......
> >
> > Also copy questions to mailing lists please.
> >
> Thanks, it works now.
> 
> #include <sys/types.h>
> #include <sys/stat.h>
> #include <fcntl.h>
> 
> #include <sys/mman.h>
> #include <stdio.h>
> 
> int main() {
>         int fd =
> open("/sys/class/pci_bus/0000:03/device/0000:03:00.0/resource5",
> O_RDWR | O_SYNC);
>         printf("fd = %d\n", fd);
>         void *addr = mmap(NULL, 512, PROT_READ, MAP_SHARED, fd, 0);
>         if(addr == MAP_FAILED)  {
>                 perror("mmap");
>         }
>         else {
>                 printf("addr = %p\n", addr);
>         }
> }
> 
> May be its time to add some hints in documentation? :-)

Good idea. Michael, are you in the mood to hack something up for
Documentation/DocBook/uio-howto.tmpl ?

Thanks,
Hans