NAME

       pciconfig_read, pciconfig_write, pciconfig_iobase - pci device information handling

LIBRARY

       Standard C library (libc, -lc)

SYNOPSIS

       #include <pci.h>

       int pciconfig_read(unsigned long bus, unsigned long dfn,
                          unsigned long off, unsigned long len,
                          unsigned char *buf);
       int pciconfig_write(unsigned long bus, unsigned long dfn,
                          unsigned long off, unsigned long len,
                          unsigned char *buf);
       int pciconfig_iobase(int 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 to indicate the error.

       pciconfig_write()
              On success, zero is returned.  On error, -1 is returned and errno is set to indicate the error.

       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 valid only 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().

STANDARDS

       Linux.

HISTORY

       Linux 2.0.26/2.1.11.

SEE ALSO

       capabilities(7)