staging: most: add ABI documentation

This patchg adds the sysfs-bus-most.txt file to the source tree.
It is needed to have an ABI description of the driver's sysfs
interface.
Signed-off-by: Christian Gromm <christian.gromm@microchip.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/most/Documentation/ABI/sysfs-bus-most.txt

+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 <usb_device 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/mostcore/add_link
+Date:		March 2017
+KernelVersion:	4.15
+Contact:	Christian Gromm <christian.gromm@microchip.com>
+Description:
+		This is used to link a channel to a component of the
+		mostcore. A link created by writing to this file is
+		referred to as pipe.
+Users:
+
+What:		/sys/bus/most/drivers/mostcore/remove_link
+Date:		March 2017
+KernelVersion:	4.15
+Contact:	Christian Gromm <christian.gromm@microchip.com>
+Description:
+		This is used to unlink a channel from a component.
+Users:
+
+What:		/sys/bus/most/drivers/mostcore/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/mostcore/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: