1What:		/sys/bus/i2c/.../idle_state
 2Date:		January 2019
 3KernelVersion:	5.2
 4Contact:	Robert Shearman <robert.shearman@att.com>
 5Description:
 6		Value that exists only for mux devices that can be
 7		written to control the behaviour of the multiplexer on
 8		idle. Possible values:
 9		-2 - disconnect on idle, i.e. deselect the last used
10		     channel, which is useful when there is a device
11		     with an address that conflicts with another
12		     device on another mux on the same parent bus.
13		-1 - leave the mux as-is, which is the most optimal
14		     setting in terms of I2C operations and is the
15		     default mode.
16		0..<nchans> - set the mux to a predetermined channel,
17		     which is useful if there is one channel that is
18		     used almost always, and you want to reduce the
19		     latency for normal operations after rare
20		     transactions on other channels