diff options
Diffstat (limited to 'Documentation/ABI/testing')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-bus-i2c-devices-pca954x | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-i2c-devices-pca954x b/Documentation/ABI/testing/sysfs-bus-i2c-devices-pca954x new file mode 100644 index 000000000000..0b0de8cd0d13 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-bus-i2c-devices-pca954x @@ -0,0 +1,20 @@ +What: /sys/bus/i2c/.../idle_state +Date: January 2019 +KernelVersion: 5.2 +Contact: Robert Shearman <robert.shearman@att.com> +Description: + Value that exists only for mux devices that can be + written to control the behaviour of the multiplexer on + idle. Possible values: + -2 - disconnect on idle, i.e. deselect the last used + channel, which is useful when there is a device + with an address that conflicts with another + device on another mux on the same parent bus. + -1 - leave the mux as-is, which is the most optimal + setting in terms of I2C operations and is the + default mode. + 0..<nchans> - set the mux to a predetermined channel, + which is useful if there is one channel that is + used almost always, and you want to reduce the + latency for normal operations after rare + transactions on other channels |