pciconfig_read

PCICONFIG_READ(2)          Linux Programmer's Manual         PCICONFIG_READ(2)



NAME
       pciconfig_read, pciconfig_write, pciconfig_iobase - pci device informa-
       tion handling

SYNOPSIS
       #include <pci.h>

       int pciconfig_read(unsigned long bus, unsigned long dfn,
            unsigned long off, unsigned long len, void *buf);
       int pciconfig_write(unsigned long bus, unsigned long dfn,
            unsigned long off, unsigned long len, void *buf);
       int pciconfig_iobase(long which, unsigned long bus,
            unsigned long devfn);

DESCRIPTION
       Most of the interaction with PCI devices is already handled by the ker-
       nel  PCI  layer,  and  thus  these calls should not normally need to be
       accessed from userspace.

       pciconfig_read
              Reads to buf from device dev at offset off value.

       pciconfig_write
              Writes from buf to device dev at offset off value.

       pciconfig_iobase
              You pass it a bus/devfn pair and  get  a  physical  address  for
              either  the  memory  offset  (for  things  like  prep,  this  is
              0xc0000000), the IO base for PIO cycles, or  the  ISA  holes  if
              any.

RETURN VALUE
       pciconfig_read
              On  success zero is returned. On error, -1 is returned and errno
              is set appropriately.

       pciconfig_write
              On success zero is returned. On error, -1 is returned and  errno
              is set appropriately.

       pciconfig_iobase
              Returns information on locations of various I/O regions in phys-
              ical memory according to the which value. Values for which  are:
              IOBASE_BRIDGE_NUMBER,  IOBASE_MEMORY,  IOBASE_IO, IOBASE_ISA_IO,
              IOBASE_ISA_MEM.

ERRORS
       ENOSYS The system has  not  implemented  these  calls  (CONFIG_PCI  not
              defined).

       EPERM  User  does  not have the CAP_SYS_ADMIN capability. This does not
              apply to pci_iobase.

       ENODEV For pci_iobase, hose value is NULL? For the other  calls,  could
              not find a slot.

       EINVAL len value is invalid. This does not apply to pci_iobase.

       EIO    I/O error.

       EOPNOTSUPP
              This  return  value is only valid for pci_iobase. It is returned
              if the value for which is invalid.

CONFORMING TO
       These calls are Linux specific, available since Linux 2.0.26/2.1.11.



Linux 2.4.19                      2003-07-14                 PCICONFIG_READ(2)