47 lines
1.6 KiB
Plaintext
47 lines
1.6 KiB
Plaintext
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Device-Tree bindings for i2c gpio driver
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Required properties:
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- compatible = "i2c-gpio";
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- sda-gpios: gpio used for the sda signal, this should be flagged as
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active high using open drain with (GPIO_ACTIVE_HIGH|GPIO_OPEN_DRAIN)
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from <dt-bindings/gpio/gpio.h> since the signal is by definition
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open drain.
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- scl-gpios: gpio used for the scl signal, this should be flagged as
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active high using open drain with (GPIO_ACTIVE_HIGH|GPIO_OPEN_DRAIN)
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from <dt-bindings/gpio/gpio.h> since the signal is by definition
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open drain.
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Optional properties:
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- i2c-gpio,scl-output-only: scl as output only
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- i2c-gpio,delay-us: delay between GPIO operations (may depend on each platform)
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- i2c-gpio,timeout-ms: timeout to get data
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Deprecated properties, do not use in new device tree sources:
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- gpios: sda and scl gpio, alternative for {sda,scl}-gpios
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- i2c-gpio,sda-open-drain: this means that something outside of our
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control has put the GPIO line used for SDA into open drain mode, and
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that something is not the GPIO chip. It is essentially an
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inconsistency flag.
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- i2c-gpio,scl-open-drain: this means that something outside of our
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control has put the GPIO line used for SCL into open drain mode, and
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that something is not the GPIO chip. It is essentially an
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inconsistency flag.
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Example nodes:
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#include <dt-bindings/gpio/gpio.h>
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i2c@0 {
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compatible = "i2c-gpio";
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sda-gpios = <&pioA 23 (GPIO_ACTIVE_HIGH|GPIO_OPEN_DRAIN)>;
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scl-gpios = <&pioA 24 (GPIO_ACTIVE_HIGH|GPIO_OPEN_DRAIN)>;
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i2c-gpio,delay-us = <2>; /* ~100 kHz */
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#address-cells = <1>;
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#size-cells = <0>;
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rv3029c2@56 {
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compatible = "rv3029c2";
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reg = <0x56>;
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};
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};
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