[PATCH 2/2] dt-bindings: i2c: add nxp,pca9541 release-delay-us property

From: Zev Weiss
Date: Mon Jan 24 2022 - 17:33:29 EST


This property can be used to reduce arbitration overhead on busy i2c
busses by retaining ownership for a brief period in anticipation of
another transaction in the near future.

Signed-off-by: Zev Weiss <zev@xxxxxxxxxxxxxxxxx>
---
Documentation/devicetree/bindings/i2c/nxp,pca9541.txt | 10 ++++++++++
1 file changed, 10 insertions(+)

diff --git a/Documentation/devicetree/bindings/i2c/nxp,pca9541.txt b/Documentation/devicetree/bindings/i2c/nxp,pca9541.txt
index 42bfc09c8918..c755da59d6ec 100644
--- a/Documentation/devicetree/bindings/i2c/nxp,pca9541.txt
+++ b/Documentation/devicetree/bindings/i2c/nxp,pca9541.txt
@@ -6,6 +6,14 @@ Required Properties:

- reg: The I2C address of the device.

+Optional Properties:
+
+ - release-delay-us: the number of microseconds to delay before
+ releasing the bus after a transaction. If unspecified the default
+ is zero (the bus is released immediately). Non-zero values can
+ reduce arbitration overhead for back-to-back transactions, at the
+ cost of delaying the other master's access to the bus.
+
The following required properties are defined externally:

- I2C arbitration bus node. See i2c-arb.txt in this directory.
@@ -13,9 +21,11 @@ Required Properties:

Example:

+ #include <dt-bindings/mux/mux.h>
i2c-arbitrator@74 {
compatible = "nxp,pca9541";
reg = <0x74>;
+ release-delay-us = <20000>;

i2c-arb {
#address-cells = <1>;
--
2.34.1