man2/pciconfig_read.2

   1 .\" Contributed by Niki A. Rahimi, LTC Security Development
   2 .\" narahimi@us.ibm.com
   3 .\" May be freely distributed.
   4 .\"
   5 .TH PCICONFIG_READ 2 2003-07-14 "Linux" "Linux Programmer's Manual"
   6 .SH NAME
   7 pciconfig_read, pciconfig_write, pciconfig_iobase \- pci device information handling
   8 .SH SYNOPSIS
   9 .nf
  10 .B #include <pci.h>
  11 .sp
  12 .BI "int pciconfig_read(unsigned long " bus ", unsigned long " dfn ,
  13 .BI "     unsigned long " off ", unsigned long " len ", void *" buf );
  14 .BI "int pciconfig_write(unsigned long " bus ", unsigned long " dfn ,
  15 .BI "     unsigned long " off ", unsigned long " len ", void *" buf );
  16 .BI "int pciconfig_iobase(long " which ", unsigned long " bus ,
  17 .BI "     unsigned long " devfn );
  18 .fi
  19 .SH DESCRIPTION
  20 .PP
  21 Most of the interaction with PCI devices is already handled by the
  22 kernel PCI layer,
  23 and thus these calls should not normally need to be accessed from userspace.
  24 .TP
  25 .BR pciconfig_read ()
  26 Reads to
  27 .I
  28 buf
  29 from device
  30 .I
  31 dev
  32 at offset
  33 .I
  34 off
  35 value.
  36 .TP
  37 .BR pciconfig_write ()
  38 Writes from
  39 .I
  40 buf
  41 to device
  42 .I
  43 dev
  44 at offset
  45 .I
  46 off
  47 value.
  48 .TP
  49 .BR pciconfig_iobase ()
  50 You pass it a bus/devfn pair and get a physical address for either the
  51 memory offset (for things like prep, this is 0xc0000000),
  52 the IO base for PIO cycles, or the ISA holes if any.
  53 .SH "RETURN VALUE"
  54 .TP
  55 .BR pciconfig_read ()
  56 On success zero is returned.
  57 On error, \-1 is returned and errno is set appropriately.
  58 .TP
  59 .BR pciconfig_write ()
  60 On success zero is returned.
  61 On error, \-1 is returned and errno is set appropriately.
  62 .TP
  63 .BR pciconfig_iobase ()
  64 Returns information on locations of various I/O
  65 regions in physical memory according to the
  66 .I which
  67 value.
  68 Values for
  69 .I which
  70 are: IOBASE_BRIDGE_NUMBER, IOBASE_MEMORY,
  71 IOBASE_IO, IOBASE_ISA_IO, IOBASE_ISA_MEM.
  72 .SH ERRORS
  73 .TP
  74 .B EINVAL
  75 .I len
  76 value is invalid.
  77 This does not apply to
  78 .BR pciconfig_iobase ().
  79 .TP
  80 .B EIO
  81 I/O error.
  82 .TP
  83 .B ENODEV
  84 For
  85 .BR pciconfig_iobase (),
  86 "hose" value is NULL?
  87 For the other calls, could not find a slot.
  88 .TP
  89 .B ENOSYS
  90 The system has not implemented these calls (CONFIG_PCI not defined).
  91 .TP
  92 .B EOPNOTSUPP
  93 This return value is only valid for
  94 .BR pciconfig_iobase ().
  95 It is returned if the value for
  96 .I
  97 which
  98 is invalid.
  99 .TP
 100 .B EPERM
 101 User does not have the \fBCAP_SYS_ADMIN\fI capability.
 102 This does not apply to
 103 .BR pciconfig_iobase ().
 104 .SH "CONFORMING TO"
 105 These calls are Linux specific, available since Linux 2.0.26/2.1.11.
 106 .SH "SEE ALSO"
 107 .BR capabilities (7)