Merge tag 'mfd-next-4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd

[sfrench/cifs-2.6.git] / Documentation / devicetree / bindings / i2c / i2c-gpio.txt

diff --git a/Documentation/devicetree/bindings/i2c/i2c-gpio.txt b/Documentation/devicetree/bindings/i2c/i2c-gpio.txt
index 4f8ec947c6bd9cada0ce90b738e9e500102e43f0..38a05562d1d2958d41520a9920a83ddfdf444418 100644 (file)
--- a/Documentation/devicetree/bindings/i2c/i2c-gpio.txt
+++ b/Documentation/devicetree/bindings/i2c/i2c-gpio.txt
@@ -2,25 +2,39 @@ Device-Tree bindings for i2c gpio driver
 
 Required properties:
        - compatible = "i2c-gpio";
-       - gpios: sda and scl gpio
-
+       - sda-gpios: gpio used for the sda signal, this should be flagged as
+         active high using open drain with (GPIO_ACTIVE_HIGH|GPIO_OPEN_DRAIN)
+         from <dt-bindings/gpio/gpio.h> since the signal is by definition
+         open drain.
+       - scl-gpios: gpio used for the scl signal, this should be flagged as
+         active high using open drain with (GPIO_ACTIVE_HIGH|GPIO_OPEN_DRAIN)
+         from <dt-bindings/gpio/gpio.h> since the signal is by definition
+         open drain.
 
 Optional properties:
-       - i2c-gpio,sda-open-drain: sda as open drain
-       - i2c-gpio,scl-open-drain: scl as open drain
        - i2c-gpio,scl-output-only: scl as output only
        - i2c-gpio,delay-us: delay between GPIO operations (may depend on each platform)
        - i2c-gpio,timeout-ms: timeout to get data
 
+Deprecated properties, do not use in new device tree sources:
+       - gpios: sda and scl gpio, alternative for {sda,scl}-gpios
+       - i2c-gpio,sda-open-drain: this means that something outside of our
+         control has put the GPIO line used for SDA into open drain mode, and
+         that something is not the GPIO chip. It is essentially an
+         inconsistency flag.
+       - i2c-gpio,scl-open-drain: this means that something outside of our
+         control has put the GPIO line used for SCL into open drain mode, and
+         that something is not the GPIO chip. It is essentially an
+         inconsistency flag.
+
 Example nodes:
 
+#include <dt-bindings/gpio/gpio.h>
+
 i2c@0 {
        compatible = "i2c-gpio";
-       gpios = <&pioA 23 0 /* sda */
-                &pioA 24 0 /* scl */
-               >;
-       i2c-gpio,sda-open-drain;
-       i2c-gpio,scl-open-drain;
+       sda-gpios = <&pioA 23 (GPIO_ACTIVE_HIGH|GPIO_OPEN_DRAIN)>;
+       scl-gpios = <&pioA 24 (GPIO_ACTIVE_HIGH|GPIO_OPEN_DRAIN)>;
        i2c-gpio,delay-us = <2>;        /* ~100 kHz */
        #address-cells = <1>;
        #size-cells = <0>;