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Device-Tree bindings for i2c gpio driver
Required properties:
- compatible = "i2c-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,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";
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>;
rv3029c2@56 {
compatible = "rv3029c2";
reg = <0x56>;
};
};
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