xref: /linux/Documentation/ABI/testing/sysfs-bus-i2c-devices-pca954x (revision 3c09ec59cdea5b132212d97154d625fd34e436dd)
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
10		===========  ===============================================
11		-2	     disconnect on idle, i.e. deselect the last used
12			     channel, which is useful when there is a device
13			     with an address that conflicts with another
14			     device on another mux on the same parent bus.
15		-1	     leave the mux as-is, which is the most optimal
16			     setting in terms of I2C operations and is the
17			     default mode.
18		0..<nchans>  set the mux to a predetermined channel,
19			     which is useful if there is one channel that is
20			     used almost always, and you want to reduce the
21			     latency for normal operations after rare
22			     transactions on other channels
23		===========  ===============================================
24