debian man page for pciconfig_read

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

NAME
       pciconfig_read, pciconfig_write, pciconfig_iobase - pci device information 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 kernel PCI layer, and thus these calls should not normally need to be
       accessed from user space.

       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 physical memory according to the which value.  Values for which are:
	      IOBASE_BRIDGE_NUMBER, IOBASE_MEMORY, IOBASE_IO, IOBASE_ISA_IO, IOBASE_ISA_MEM.

ERRORS
       EINVAL len value is invalid.  This does not apply to pciconfig_iobase().

       EIO    I/O error.

       ENODEV For pciconfig_iobase(), "hose" value is NULL.  For the other calls, could not find a slot.

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

       EOPNOTSUPP
	      This return value is only valid for pciconfig_iobase().  It is returned if the value for which is invalid.

       EPERM  User does not have the CAP_SYS_ADMIN capability.	This does not apply to pciconfig_iobase().

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

SEE ALSO
       capabilities(7)

COLOPHON
       This page is part of release 3.44 of the Linux man-pages project.  A description of the project, and information about reporting bugs,  can
       be found at http://www.kernel.org/doc/man-pages/.

Linux								    2003-07-14							 PCICONFIG_READ(2)