tree 1ce4aff048e1b1a428444b7ae087dba8519854de
parent 24334a12533e9ac70dcb467ccd629f190afc5361
author Brice Goglin <brice@myri.com> 1157003715 -0400
committer Greg Kroah-Hartman <gregkh@suse.de> 1159317832 -0700

MSI: Export the PCI_BUS_FLAGS_NO_MSI flag in sysfs

Export the PCI_BUS_FLAGS_NO_MSI flag of a PCI bus in the sysfs files
of its parent device and make it writable. Could be used to:
* disable MSI on a device which has not been blacklisted yet
* allow MSI when some setpci hacks enable MSI support (for instance
  on the ServerWorks HT2000 chipset where the MSI HT cap is disabled
  by default).
Architecture where some bus have no parent chipset cannot use this
strategy to change MSI support.

If the chipset does not have a subordinate bus, its 'bus_msi' file
is empty.

Also document and warn about the possible danger of changing the flag.

Signed-off-by: Brice Goglin <brice@myri.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>