PCI/sysfs: add per pci device msi[x] irq listing (v5)

This patch adds a per-pci-device subdirectory in sysfs called:
/sys/bus/pci/devices/<device>/msi_irqs

This sub-directory exports the set of msi vectors allocated by a given
pci device, by creating a numbered sub-directory for each vector beneath
msi_irqs.  For each vector various attributes can be exported.
Currently the only attribute is called mode, which tracks the
operational mode of that vector (msi vs. msix)

Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

1 files changed, 18 insertions, 0 deletions

diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci
index 349ecf26ce10..34f51100f029 100644
--- a/Documentation/ABI/testing/sysfs-bus-pci
+++ b/Documentation/ABI/testing/sysfs-bus-pci
@@ -66,6 +66,24 @@ Description:
                 re-discover previously removed devices.
                 Depends on CONFIG_HOTPLUG.
 
+What:           /sys/bus/pci/devices/.../msi_irqs/
+Date:           September, 2011
+Contact:        Neil Horman <nhorman@tuxdriver.com>
+Description:
+                The /sys/devices/.../msi_irqs directory contains a variable set
+                of sub-directories, with each sub-directory being named after a
+                corresponding msi irq vector allocated to that device.  Each
+                numbered sub-directory N contains attributes of that irq.
+                Note that this directory is not created for device drivers which
+                do not support msi irqs
+
+What:           /sys/bus/pci/devices/.../msi_irqs/<N>/mode
+Date:           September 2011
+Contact:        Neil Horman <nhorman@tuxdriver.com>
+Description:
+                This attribute indicates the mode that the irq vector named by
+                the parent directory is in (msi vs. msix)
+
 What:           /sys/bus/pci/devices/.../remove
 Date:           January 2009
 Contact:        Linux PCI developers <linux-pci@vger.kernel.org>