ABI: sysfs-bus-pci: add documentation for modalias

Even being available since 2005, there's no documentation for
modalias.

Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/9ceb1fcdbef3c0d2d0368dcc2f19084a3e529ad1.1632750608.git.mchehab+huawei@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci
index 191cbe9ae5edab35895e9099048c13b715e18054..1eeac7f596722698e55e1da6450ac3437d0571eb 100644 (file)
--- a/Documentation/ABI/testing/sysfs-bus-pci
+++ b/Documentation/ABI/testing/sysfs-bus-pci
@@ -187,6 +187,24 @@ Description:
                The symbolic link points to the PCI device sysfs entry of the
                Physical Function this device associates with.
 
+What:          /sys/bus/pci/devices/.../modalias
+Date:          May 2005
+Contact:       Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+Description:
+               This attribute indicates the PCI ID of the device object.
+
+               That is in the format:
+               pci:vXXXXXXXXdXXXXXXXXsvXXXXXXXXsdXXXXXXXXbcXXscXXiXX,
+               where:
+
+                   - vXXXXXXXX contains the vendor ID;
+                   - dXXXXXXXX contains the device ID;
+                   - svXXXXXXXX contains the sub-vendor ID;
+                   - sdXXXXXXXX contains the subsystem device ID;
+                   - bcXX contains the device class;
+                   - scXX contains the device subclass;
+                   - iXX contains the device class programming interface.
+
 What:          /sys/bus/pci/slots/.../module
 Date:          June 2009
 Contact:       linux-pci@vger.kernel.org