v4.19.13 snapshot.
diff --git a/Documentation/ABI/testing/sysfs-bus-css b/Documentation/ABI/testing/sysfs-bus-css
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+What: /sys/bus/css/devices/.../type
+Date: March 2008
+Contact: Cornelia Huck <cornelia.huck@de.ibm.com>
+ linux-s390@vger.kernel.org
+Description: Contains the subchannel type, as reported by the hardware.
+ This attribute is present for all subchannel types.
+
+What: /sys/bus/css/devices/.../modalias
+Date: March 2008
+Contact: Cornelia Huck <cornelia.huck@de.ibm.com>
+ linux-s390@vger.kernel.org
+Description: Contains the module alias as reported with uevents.
+ It is of the format css:t<type> and present for all
+ subchannel types.
+
+What: /sys/bus/css/drivers/io_subchannel/.../chpids
+Date: December 2002
+Contact: Cornelia Huck <cornelia.huck@de.ibm.com>
+ linux-s390@vger.kernel.org
+Description: Contains the ids of the channel paths used by this
+ subchannel, as reported by the channel subsystem
+ during subchannel recognition.
+ Note: This is an I/O-subchannel specific attribute.
+Users: s390-tools, HAL
+
+What: /sys/bus/css/drivers/io_subchannel/.../pimpampom
+Date: December 2002
+Contact: Cornelia Huck <cornelia.huck@de.ibm.com>
+ linux-s390@vger.kernel.org
+Description: Contains the PIM/PAM/POM values, as reported by the
+ channel subsystem when last queried by the common I/O
+ layer (this implies that this attribute is not necessarily
+ in sync with the values current in the channel subsystem).
+ Note: This is an I/O-subchannel specific attribute.
+Users: s390-tools, HAL