PCI: Expose PCI VPD through sysfs

Vital Product Data (VPD) may be exposed by PCI devices in several
ways.  It is generally unsafe to read this information through the
existing interfaces to user-land because of stateful interfaces.

This adds:
- abstract operations for VPD access (struct pci_vpd_ops)
- VPD state information in struct pci_dev (struct pci_vpd)
- an implementation of the VPD access method specified in PCI 2.2
  (in access.c)
- a 'vpd' binary file in sysfs directories for PCI devices with VPD
  operations defined

It adds a probe for PCI 2.2 VPD in pci_scan_device() and release of
VPD state in pci_release_dev().

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 11 insertions, 0 deletions

diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci
new file mode 100644
index 000000000000..ceddcff4082a
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-bus-pci
@@ -0,0 +1,11 @@
+What:           /sys/bus/pci/devices/.../vpd
+Date:           February 2008
+Contact:        Ben Hutchings <bhutchings@solarflare.com>
+Description:
+                A file named vpd in a device directory will be a
+                binary file containing the Vital Product Data for the
+                device.  It should follow the VPD format defined in
+                PCI Specification 2.1 or 2.2, but users should consider
+                that some devices may have malformatted data.  If the
+                underlying VPD has a writable section then the
+                corresponding section of this file will be writable.