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-rw-r--r--Documentation/ABI/testing/configfs-most196
-rw-r--r--Documentation/ABI/testing/sysfs-bus-counter-104-quad-825
-rw-r--r--Documentation/ABI/testing/sysfs-bus-iio-adc-ad719224
-rw-r--r--Documentation/ABI/testing/sysfs-bus-most295
-rw-r--r--Documentation/ABI/testing/sysfs-class-typec23
-rw-r--r--Documentation/ABI/testing/sysfs-driver-uacce39
-rw-r--r--Documentation/ABI/testing/sysfs-kernel-uids14
-rw-r--r--Documentation/ABI/testing/sysfs-tty7
8 files changed, 596 insertions, 27 deletions
diff --git a/Documentation/ABI/testing/configfs-most b/Documentation/ABI/testing/configfs-most
new file mode 100644
index 000000000000..ed67a4d9f6d6
--- /dev/null
+++ b/Documentation/ABI/testing/configfs-most
@@ -0,0 +1,196 @@
+What: /sys/kernel/config/most_<component>
+Date: March 8, 2019
+KernelVersion: 5.2
+Description: Interface is used to configure and connect device channels
+ to component drivers.
+
+ Attributes are visible only when configfs is mounted. To mount
+ configfs in /sys/kernel/config directory use:
+ # mount -t configfs none /sys/kernel/config/
+
+
+What: /sys/kernel/config/most_cdev/<link>
+Date: March 8, 2019
+KernelVersion: 5.2
+Description:
+ The attributes:
+
+ buffer_size configure the buffer size for this channel
+
+ subbuffer_size configure the sub-buffer size for this channel
+ (needed for synchronous and isochrnous data)
+
+
+ num_buffers configure number of buffers used for this
+ channel
+
+ datatype configure type of data that will travel over
+ this channel
+
+ direction configure whether this link will be an input
+ or output
+
+ dbr_size configure DBR data buffer size (this is used
+ for MediaLB communication only)
+
+ packets_per_xact
+ configure the number of packets that will be
+ collected from the network before being
+ transmitted via USB (this is used for USB
+ communication only)
+
+ device name of the device the link is to be attached to
+
+ channel name of the channel the link is to be attached to
+
+ comp_params pass parameters needed by some components
+
+ create_link write '1' to this attribute to trigger the
+ creation of the link. In case of speculative
+ configuration, the creation is post-poned until
+ a physical device is being attached to the bus.
+
+ destroy_link write '1' to this attribute to destroy an
+ active link
+
+What: /sys/kernel/config/most_video/<link>
+Date: March 8, 2019
+KernelVersion: 5.2
+Description:
+ The attributes:
+
+ buffer_size configure the buffer size for this channel
+
+ subbuffer_size configure the sub-buffer size for this channel
+ (needed for synchronous and isochrnous data)
+
+
+ num_buffers configure number of buffers used for this
+ channel
+
+ datatype configure type of data that will travel over
+ this channel
+
+ direction configure whether this link will be an input
+ or output
+
+ dbr_size configure DBR data buffer size (this is used
+ for MediaLB communication only)
+
+ packets_per_xact
+ configure the number of packets that will be
+ collected from the network before being
+ transmitted via USB (this is used for USB
+ communication only)
+
+ device name of the device the link is to be attached to
+
+ channel name of the channel the link is to be attached to
+
+ comp_params pass parameters needed by some components
+
+ create_link write '1' to this attribute to trigger the
+ creation of the link. In case of speculative
+ configuration, the creation is post-poned until
+ a physical device is being attached to the bus.
+
+ destroy_link write '1' to this attribute to destroy an
+ active link
+
+What: /sys/kernel/config/most_net/<link>
+Date: March 8, 2019
+KernelVersion: 5.2
+Description:
+ The attributes:
+
+ buffer_size configure the buffer size for this channel
+
+ subbuffer_size configure the sub-buffer size for this channel
+ (needed for synchronous and isochrnous data)
+
+
+ num_buffers configure number of buffers used for this
+ channel
+
+ datatype configure type of data that will travel over
+ this channel
+
+ direction configure whether this link will be an input
+ or output
+
+ dbr_size configure DBR data buffer size (this is used
+ for MediaLB communication only)
+
+ packets_per_xact
+ configure the number of packets that will be
+ collected from the network before being
+ transmitted via USB (this is used for USB
+ communication only)
+
+ device name of the device the link is to be attached to
+
+ channel name of the channel the link is to be attached to
+
+ comp_params pass parameters needed by some components
+
+ create_link write '1' to this attribute to trigger the
+ creation of the link. In case of speculative
+ configuration, the creation is post-poned until
+ a physical device is being attached to the bus.
+
+ destroy_link write '1' to this attribute to destroy an
+ active link
+
+What: /sys/kernel/config/most_sound/<card>
+Date: March 8, 2019
+KernelVersion: 5.2
+Description:
+ The attributes:
+
+ create_card write '1' to this attribute to trigger the
+ registration of the sound card with the ALSA
+ subsystem.
+
+What: /sys/kernel/config/most_sound/<card>/<link>
+Date: March 8, 2019
+KernelVersion: 5.2
+Description:
+ The attributes:
+
+ buffer_size configure the buffer size for this channel
+
+ subbuffer_size configure the sub-buffer size for this channel
+ (needed for synchronous and isochrnous data)
+
+
+ num_buffers configure number of buffers used for this
+ channel
+
+ datatype configure type of data that will travel over
+ this channel
+
+ direction configure whether this link will be an input
+ or output
+
+ dbr_size configure DBR data buffer size (this is used
+ for MediaLB communication only)
+
+ packets_per_xact
+ configure the number of packets that will be
+ collected from the network before being
+ transmitted via USB (this is used for USB
+ communication only)
+
+ device name of the device the link is to be attached to
+
+ channel name of the channel the link is to be attached to
+
+ comp_params pass parameters needed by some components
+
+ create_link write '1' to this attribute to trigger the
+ creation of the link. In case of speculative
+ configuration, the creation is post-poned until
+ a physical device is being attached to the bus.
+
+ destroy_link write '1' to this attribute to destroy an
+ active link
diff --git a/Documentation/ABI/testing/sysfs-bus-counter-104-quad-8 b/Documentation/ABI/testing/sysfs-bus-counter-104-quad-8
index 46b1f33b2fce..eac32180c40d 100644
--- a/Documentation/ABI/testing/sysfs-bus-counter-104-quad-8
+++ b/Documentation/ABI/testing/sysfs-bus-counter-104-quad-8
@@ -1,3 +1,28 @@
+What: /sys/bus/counter/devices/counterX/signalY/cable_fault
+KernelVersion: 5.7
+Contact: linux-iio@vger.kernel.org
+Description:
+ Read-only attribute that indicates whether a differential
+ encoder cable fault (not connected or loose wires) is detected
+ for the respective channel of Signal Y. Valid attribute values
+ are boolean. Detection must first be enabled via the
+ corresponding cable_fault_enable attribute.
+
+What: /sys/bus/counter/devices/counterX/signalY/cable_fault_enable
+KernelVersion: 5.7
+Contact: linux-iio@vger.kernel.org
+Description:
+ Whether detection of differential encoder cable faults for the
+ respective channel of Signal Y is enabled. Valid attribute
+ values are boolean.
+
+What: /sys/bus/counter/devices/counterX/signalY/filter_clock_prescaler
+KernelVersion: 5.7
+Contact: linux-iio@vger.kernel.org
+Description:
+ Filter clock factor for input Signal Y. This prescaler value
+ affects the inputs of both quadrature pair signals.
+
What: /sys/bus/counter/devices/counterX/signalY/index_polarity
KernelVersion: 5.2
Contact: linux-iio@vger.kernel.org
diff --git a/Documentation/ABI/testing/sysfs-bus-iio-adc-ad7192 b/Documentation/ABI/testing/sysfs-bus-iio-adc-ad7192
index 7627d3be08f5..f8315202c8f0 100644
--- a/Documentation/ABI/testing/sysfs-bus-iio-adc-ad7192
+++ b/Documentation/ABI/testing/sysfs-bus-iio-adc-ad7192
@@ -2,17 +2,22 @@ What: /sys/bus/iio/devices/iio:deviceX/ac_excitation_en
KernelVersion:
Contact: linux-iio@vger.kernel.org
Description:
- Reading gives the state of AC excitation.
- Writing '1' enables AC excitation.
+ This attribute, if available, is used to enable the AC
+ excitation mode found on some converters. In ac excitation mode,
+ the polarity of the excitation voltage is reversed on
+ alternate cycles, to eliminate DC errors.
What: /sys/bus/iio/devices/iio:deviceX/bridge_switch_en
KernelVersion:
Contact: linux-iio@vger.kernel.org
Description:
- This bridge switch is used to disconnect it when there is a
- need to minimize the system current consumption.
- Reading gives the state of the bridge switch.
- Writing '1' enables the bridge switch.
+ This attribute, if available, is used to close or open the
+ bridge power down switch found on some converters.
+ In bridge applications, such as strain gauges and load cells,
+ the bridge itself consumes the majority of the current in the
+ system. To minimize the current consumption of the system,
+ the bridge can be disconnected (when it is not being used
+ using the bridge_switch_en attribute.
What: /sys/bus/iio/devices/iio:deviceX/in_voltagex_sys_calibration
KernelVersion:
@@ -21,6 +26,13 @@ Description:
Initiates the system calibration procedure. This is done on a
single channel at a time. Write '1' to start the calibration.
+What: /sys/bus/iio/devices/iio:deviceX/in_voltage2-voltage2_shorted_raw
+KernelVersion:
+Contact: linux-iio@vger.kernel.org
+Description:
+ Measure voltage from AIN2 pin connected to AIN(+)
+ and AIN(-) shorted.
+
What: /sys/bus/iio/devices/iio:deviceX/in_voltagex_sys_calibration_mode_available
KernelVersion:
Contact: linux-iio@vger.kernel.org
diff --git a/Documentation/ABI/testing/sysfs-bus-most b/Documentation/ABI/testing/sysfs-bus-most
new file mode 100644
index 000000000000..6b1d06e3285e
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-bus-most
@@ -0,0 +1,295 @@
+What: /sys/bus/most/devices/.../description
+Date: March 2017
+KernelVersion: 4.15
+Contact: Christian Gromm <christian.gromm@microchip.com>
+Description:
+ Provides information about the interface type and the physical
+ location of the device. Hardware attached via USB, for instance,
+ might return <1-1.1:1.0>
+Users:
+
+What: /sys/bus/most/devices/.../interface
+Date: March 2017
+KernelVersion: 4.15
+Contact: Christian Gromm <christian.gromm@microchip.com>
+Description:
+ Indicates the type of peripheral interface the device uses.
+Users:
+
+What: /sys/bus/most/devices/.../dci
+Date: June 2016
+KernelVersion: 4.15
+Contact: Christian Gromm <christian.gromm@microchip.com>
+Description:
+ If the network interface controller is attached via USB, a dci
+ directory is created that allows applications to read and
+ write the controller's DCI registers.
+Users:
+
+What: /sys/bus/most/devices/.../dci/arb_address
+Date: June 2016
+KernelVersion: 4.15
+Contact: Christian Gromm <christian.gromm@microchip.com>
+Description:
+ This is used to set an arbitrary DCI register address an
+ application wants to read from or write to.
+Users:
+
+What: /sys/bus/most/devices/.../dci/arb_value
+Date: June 2016
+KernelVersion: 4.15
+Contact: Christian Gromm <christian.gromm@microchip.com>
+Description:
+ This is used to read and write the DCI register whose address
+ is stored in arb_address.
+Users:
+
+What: /sys/bus/most/devices/.../dci/mep_eui48_hi
+Date: June 2016
+KernelVersion: 4.15
+Contact: Christian Gromm <christian.gromm@microchip.com>
+Description:
+ This is used to check and configure the MAC address.
+Users:
+
+What: /sys/bus/most/devices/.../dci/mep_eui48_lo
+Date: June 2016
+KernelVersion: 4.15
+Contact: Christian Gromm <christian.gromm@microchip.com>
+Description:
+ This is used to check and configure the MAC address.
+Users:
+
+What: /sys/bus/most/devices/.../dci/mep_eui48_mi
+Date: June 2016
+KernelVersion: 4.15
+Contact: Christian Gromm <christian.gromm@microchip.com>
+Description:
+ This is used to check and configure the MAC address.
+Users:
+
+What: /sys/bus/most/devices/.../dci/mep_filter
+Date: June 2016
+KernelVersion: 4.15
+Contact: Christian Gromm <christian.gromm@microchip.com>
+Description:
+ This is used to check and configure the MEP filter address.
+Users:
+
+What: /sys/bus/most/devices/.../dci/mep_hash0
+Date: June 2016
+KernelVersion: 4.15
+Contact: Christian Gromm <christian.gromm@microchip.com>
+Description:
+ This is used to check and configure the MEP hash table.
+Users:
+
+What: /sys/bus/most/devices/.../dci/mep_hash1
+Date: June 2016
+KernelVersion: 4.15
+Contact: Christian Gromm <christian.gromm@microchip.com>
+Description:
+ This is used to check and configure the MEP hash table.
+Users:
+
+What: /sys/bus/most/devices/.../dci/mep_hash2
+Date: June 2016
+KernelVersion: 4.15
+Contact: Christian Gromm <christian.gromm@microchip.com>
+Description:
+ This is used to check and configure the MEP hash table.
+Users:
+
+What: /sys/bus/most/devices/.../dci/mep_hash3
+Date: June 2016
+KernelVersion: 4.15
+Contact: Christian Gromm <christian.gromm@microchip.com>
+Description:
+ This is used to check and configure the MEP hash table.
+Users:
+
+What: /sys/bus/most/devices/.../dci/ni_state
+Date: June 2016
+KernelVersion: 4.15
+Contact: Christian Gromm <christian.gromm@microchip.com>
+Description:
+ Indicates the current network interface state.
+Users:
+
+What: /sys/bus/most/devices/.../dci/node_address
+Date: June 2016
+KernelVersion: 4.15
+Contact: Christian Gromm <christian.gromm@microchip.com>
+Description:
+ Indicates the current node address.
+Users:
+
+What: /sys/bus/most/devices/.../dci/node_position
+Date: June 2016
+KernelVersion: 4.15
+Contact: Christian Gromm <christian.gromm@microchip.com>
+Description:
+ Indicates the current node position.
+Users:
+
+What: /sys/bus/most/devices/.../dci/packet_bandwidth
+Date: June 2016
+KernelVersion: 4.15
+Contact: Christian Gromm <christian.gromm@microchip.com>
+Description:
+ Indicates the configured packet bandwidth.
+Users:
+
+What: /sys/bus/most/devices/.../dci/sync_ep
+Date: June 2016
+KernelVersion: 4.15
+Contact: Christian Gromm <christian.gromm@microchip.com>
+Description:
+ Triggers the controller's synchronization process for a certain
+ endpoint.
+Users:
+
+What: /sys/bus/most/devices/.../<channel>/
+Date: March 2017
+KernelVersion: 4.15
+Contact: Christian Gromm <christian.gromm@microchip.com>
+Description:
+ For every channel of the device a directory is created, whose
+ name is dictated by the HDM. This enables an application to
+ collect information about the channel's capabilities and
+ configure it.
+Users:
+
+What: /sys/bus/most/devices/.../<channel>/available_datatypes
+Date: March 2017
+KernelVersion: 4.15
+Contact: Christian Gromm <christian.gromm@microchip.com>
+Description:
+ Indicates the data types the current channel can transport.
+Users:
+
+What: /sys/bus/most/devices/.../<channel>/available_directions
+Date: March 2017
+KernelVersion: 4.15
+Contact: Christian Gromm <christian.gromm@microchip.com>
+Description:
+ Indicates the directions the current channel is capable of.
+Users:
+
+What: /sys/bus/most/devices/.../<channel>/number_of_packet_buffers
+Date: March 2017
+KernelVersion: 4.15
+Contact: Christian Gromm <christian.gromm@microchip.com>
+Description:
+ Indicates the number of packet buffers the current channel can
+ handle.
+Users:
+
+What: /sys/bus/most/devices/.../<channel>/number_of_stream_buffers
+Date: March 2017
+KernelVersion: 4.15
+Contact: Christian Gromm <christian.gromm@microchip.com>
+Description:
+ Indicates the number of streaming buffers the current channel can
+ handle.
+Users:
+
+What: /sys/bus/most/devices/.../<channel>/size_of_packet_buffer
+Date: March 2017
+KernelVersion: 4.15
+Contact: Christian Gromm <christian.gromm@microchip.com>
+Description:
+ Indicates the size of a packet buffer the current channel can
+ handle.
+Users:
+
+What: /sys/bus/most/devices/.../<channel>/size_of_stream_buffer
+Date: March 2017
+KernelVersion: 4.15
+Contact: Christian Gromm <christian.gromm@microchip.com>
+Description:
+ Indicates the size of a streaming buffer the current channel can
+ handle.
+Users:
+
+What: /sys/bus/most/devices/.../<channel>/set_number_of_buffers
+Date: March 2017
+KernelVersion: 4.15
+Contact: Christian Gromm <christian.gromm@microchip.com>
+Description:
+ This is to configure the number of buffers of the current channel.
+Users:
+
+What: /sys/bus/most/devices/.../<channel>/set_buffer_size
+Date: March 2017
+KernelVersion: 4.15
+Contact: Christian Gromm <christian.gromm@microchip.com>
+Description:
+ This is to configure the size of a buffer of the current channel.
+Users:
+
+What: /sys/bus/most/devices/.../<channel>/set_direction
+Date: March 2017
+KernelVersion: 4.15
+Contact: Christian Gromm <christian.gromm@microchip.com>
+Description:
+ This is to configure the direction of the current channel.
+ The following strings will be accepted:
+ 'dir_tx',
+ 'dir_rx'
+Users:
+
+What: /sys/bus/most/devices/.../<channel>/set_datatype
+Date: March 2017
+KernelVersion: 4.15
+Contact: Christian Gromm <christian.gromm@microchip.com>
+Description:
+ This is to configure the data type of the current channel.
+ The following strings will be accepted:
+ 'control',
+ 'async',
+ 'sync',
+ 'isoc_avp'
+Users:
+
+What: /sys/bus/most/devices/.../<channel>/set_subbuffer_size
+Date: March 2017
+KernelVersion: 4.15
+Contact: Christian Gromm <christian.gromm@microchip.com>
+Description:
+ This is to configure the subbuffer size of the current channel.
+Users:
+
+What: /sys/bus/most/devices/.../<channel>/set_packets_per_xact
+Date: March 2017
+KernelVersion: 4.15
+Contact: Christian Gromm <christian.gromm@microchip.com>
+Description:
+ This is to configure the number of packets per transaction of
+ the current channel. This is only needed network interface
+ controller is attached via USB.
+Users:
+
+What: /sys/bus/most/devices/.../<channel>/channel_starving
+Date: March 2017
+KernelVersion: 4.15
+Contact: Christian Gromm <christian.gromm@microchip.com>
+Description:
+ Indicates whether current channel ran out of buffers.
+Users:
+
+What: /sys/bus/most/drivers/most_core/components
+Date: March 2017
+KernelVersion: 4.15
+Contact: Christian Gromm <christian.gromm@microchip.com>
+Description:
+ This is used to retrieve a list of registered components.
+Users:
+
+What: /sys/bus/most/drivers/most_core/links
+Date: March 2017
+KernelVersion: 4.15
+Contact: Christian Gromm <christian.gromm@microchip.com>
+Description:
+ This is used to retrieve a list of established links.
+Users:
diff --git a/Documentation/ABI/testing/sysfs-class-typec b/Documentation/ABI/testing/sysfs-class-typec
index d7647b258c3c..b834671522d6 100644
--- a/Documentation/ABI/testing/sysfs-class-typec
+++ b/Documentation/ABI/testing/sysfs-class-typec
@@ -20,13 +20,13 @@ Date: April 2017
Contact: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Description:
The supported power roles. This attribute can be used to request
- power role swap on the port when the port supports USB Power
- Delivery. Swapping is supported as synchronous operation, so
- write(2) to the attribute will not return until the operation
- has finished. The attribute is notified about role changes so
- that poll(2) on the attribute wakes up. Change on the role will
- also generate uevent KOBJ_CHANGE. The current role is show in
- brackets, for example "[source] sink" when in source mode.
+ power role swap on the port. Swapping is supported as
+ synchronous operation, so write(2) to the attribute will not
+ return until the operation has finished. The attribute is
+ notified about role changes so that poll(2) on the attribute
+ wakes up. Change on the role will also generate uevent
+ KOBJ_CHANGE. The current role is show in brackets, for example
+ "[source] sink" when in source mode.
Valid values: source, sink
@@ -108,6 +108,15 @@ Contact: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Description:
Revision number of the supported USB Type-C specification.
+What: /sys/class/typec/<port>/orientation
+Date: February 2020
+Contact: Badhri Jagan Sridharan <badhri@google.com>
+Description:
+ Indicates the active orientation of the Type-C connector.
+ Valid values:
+ - "normal": CC1 orientation
+ - "reverse": CC2 orientation
+ - "unknown": Orientation cannot be determined.
USB Type-C partner devices (eg. /sys/class/typec/port0-partner/)
diff --git a/Documentation/ABI/testing/sysfs-driver-uacce b/Documentation/ABI/testing/sysfs-driver-uacce
new file mode 100644
index 000000000000..08f2591138af
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-driver-uacce
@@ -0,0 +1,39 @@
+What: /sys/class/uacce/<dev_name>/api
+Date: Feb 2020
+KernelVersion: 5.7
+Contact: linux-accelerators@lists.ozlabs.org
+Description: Api of the device
+ Can be any string and up to userspace to parse.
+ Application use the api to match the correct driver
+
+What: /sys/class/uacce/<dev_name>/flags
+Date: Feb 2020
+KernelVersion: 5.7
+Contact: linux-accelerators@lists.ozlabs.org
+Description: Attributes of the device, see UACCE_DEV_xxx flag defined in uacce.h
+
+What: /sys/class/uacce/<dev_name>/available_instances
+Date: Feb 2020
+KernelVersion: 5.7
+Contact: linux-accelerators@lists.ozlabs.org
+Description: Available instances left of the device
+ Return -ENODEV if uacce_ops get_available_instances is not provided
+
+What: /sys/class/uacce/<dev_name>/algorithms
+Date: Feb 2020
+KernelVersion: 5.7
+Contact: linux-accelerators@lists.ozlabs.org
+Description: Algorithms supported by this accelerator, separated by new line.
+ Can be any string and up to userspace to parse.
+
+What: /sys/class/uacce/<dev_name>/region_mmio_size
+Date: Feb 2020
+KernelVersion: 5.7
+Contact: linux-accelerators@lists.ozlabs.org
+Description: Size (bytes) of mmio region queue file
+
+What: /sys/class/uacce/<dev_name>/region_dus_size
+Date: Feb 2020
+KernelVersion: 5.7
+Contact: linux-accelerators@lists.ozlabs.org
+Description: Size (bytes) of dus region queue file
diff --git a/Documentation/ABI/testing/sysfs-kernel-uids b/Documentation/ABI/testing/sysfs-kernel-uids
deleted file mode 100644
index 4182b7061816..000000000000
--- a/Documentation/ABI/testing/sysfs-kernel-uids
+++ /dev/null
@@ -1,14 +0,0 @@
-What: /sys/kernel/uids/<uid>/cpu_shares
-Date: December 2007
-Contact: Dhaval Giani <dhaval@linux.vnet.ibm.com>
- Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
-Description:
- The /sys/kernel/uids/<uid>/cpu_shares tunable is used
- to set the cpu bandwidth a user is allowed. This is a
- propotional value. What that means is that if there
- are two users logged in, each with an equal number of
- shares, then they will get equal CPU bandwidth. Another
- example would be, if User A has shares = 1024 and user
- B has shares = 2048, User B will get twice the CPU
- bandwidth user A will. For more details refer
- Documentation/scheduler/sched-design-CFS.rst
diff --git a/Documentation/ABI/testing/sysfs-tty b/Documentation/ABI/testing/sysfs-tty
index 9eb3c2b6b040..e157130a6792 100644
--- a/Documentation/ABI/testing/sysfs-tty
+++ b/Documentation/ABI/testing/sysfs-tty
@@ -154,3 +154,10 @@ Description:
device specification. For example, when user sets 7bytes on
16550A, which has 1/4/8/14 bytes trigger, the RX trigger is
automatically changed to 4 bytes.
+
+What: /sys/class/tty/ttyS0/console
+Date: February 2020
+Contact: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
+Description:
+ Allows user to detach or attach back the given device as
+ kernel console. It shows and accepts a boolean variable.