v4.19.13 snapshot.
diff --git a/Documentation/ABI/stable/sysfs-class-rfkill b/Documentation/ABI/stable/sysfs-class-rfkill
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+rfkill - radio frequency (RF) connector kill switch support
+
+For details to this subsystem look at Documentation/rfkill.txt.
+
+For the deprecated /sys/class/rfkill/*/claim knobs of this interface look in
+Documentation/ABI/removed/sysfs-class-rfkill.
+
+What: /sys/class/rfkill
+Date: 09-Jul-2007
+KernelVersion: v2.6.22
+Contact: linux-wireless@vger.kernel.org,
+Description: The rfkill class subsystem folder.
+ Each registered rfkill driver is represented by an rfkillX
+ subfolder (X being an integer >= 0).
+
+
+What: /sys/class/rfkill/rfkill[0-9]+/name
+Date: 09-Jul-2007
+KernelVersion v2.6.22
+Contact: linux-wireless@vger.kernel.org
+Description: Name assigned by driver to this key (interface or driver name).
+Values: arbitrary string.
+
+
+What: /sys/class/rfkill/rfkill[0-9]+/type
+Date: 09-Jul-2007
+KernelVersion v2.6.22
+Contact: linux-wireless@vger.kernel.org
+Description: Driver type string ("wlan", "bluetooth", etc).
+Values: See include/linux/rfkill.h.
+
+
+What: /sys/class/rfkill/rfkill[0-9]+/persistent
+Date: 09-Jul-2007
+KernelVersion v2.6.22
+Contact: linux-wireless@vger.kernel.org
+Description: Whether the soft blocked state is initialised from non-volatile
+ storage at startup.
+Values: A numeric value.
+ 0: false
+ 1: true
+
+
+What: /sys/class/rfkill/rfkill[0-9]+/state
+Date: 09-Jul-2007
+KernelVersion v2.6.22
+Contact: linux-wireless@vger.kernel.org
+Description: Current state of the transmitter.
+ This file was scheduled to be removed in 2014, but due to its
+ large number of users it will be sticking around for a bit
+ longer. Despite it being marked as stable, the newer "hard" and
+ "soft" interfaces should be preferred, since it is not possible
+ to express the 'soft and hard block' state of the rfkill driver
+ through this interface. There will likely be another attempt to
+ remove it in the future.
+Values: A numeric value.
+ 0: RFKILL_STATE_SOFT_BLOCKED
+ transmitter is turned off by software
+ 1: RFKILL_STATE_UNBLOCKED
+ transmitter is (potentially) active
+ 2: RFKILL_STATE_HARD_BLOCKED
+ transmitter is forced off by something outside of
+ the driver's control.
+
+
+What: /sys/class/rfkill/rfkill[0-9]+/hard
+Date: 12-March-2010
+KernelVersion v2.6.34
+Contact: linux-wireless@vger.kernel.org
+Description: Current hardblock state. This file is read only.
+Values: A numeric value.
+ 0: inactive
+ The transmitter is (potentially) active.
+ 1: active
+ The transmitter is forced off by something outside of
+ the driver's control.
+
+
+What: /sys/class/rfkill/rfkill[0-9]+/soft
+Date: 12-March-2010
+KernelVersion v2.6.34
+Contact: linux-wireless@vger.kernel.org
+Description: Current softblock state. This file is read and write.
+Values: A numeric value.
+ 0: inactive
+ The transmitter is (potentially) active.
+ 1: active
+ The transmitter is turned off by software.