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nordic,nrf-twi

Vendor: Nordic Semiconductor

Description

These nodes are “i2c” bus nodes.

Nordic nRF family TWI (TWI master).

This binding can be used for nodes which can represent TWI
peripherals. When a single SoC peripheral ID corresponds to multiple
I2C peripherals (like TWI or TWIM), the corresponding devicetree
nodes must be set up to select TWI before use.

To select TWI, set the node's "compatible" to "nordic,nrf-twi" and
its "status" to "okay", e.g. using an overlay file like this:

    /* This is for TWI0 -- change to "i2c1" for TWI1. */
    &i2c0 {
            compatible = "nordic,nrf-twi";
            status = "okay";
            /* other property settings can go here */
    };

You can use either of these options to check TWI availability on
your SoC:

    1. Check the peripheral Instantiation table in the Memory
       section of your SoC's Product Specification document.
       A "TWI0" instance in the table means "i2c0" in the devicetree
       can be used with this binding, and similarly for "TWI1".

    2. Open your SoC's .dtsi file and look for a node definition that
       documents TWI support, like this:

           i2c0: i2c@40003000 {
                   /*
                    * This i2c node can be TWI, [...].
                    */
                   ...
           };

 If your SoC only has TWIM and TWIS I2C peripherals, you cannot use
 this binding. See the "nordic,nrf-twim" binding instead.

Properties

Properties not inherited from the base binding file.

Name

Type

Details

pinctrl-0

phandles

Pin configuration/s for the first state. Content is specific to the
selected pin controller driver implementation.

This property is required.

easydma-maxcnt-bits

int

Maximum number of bits available in the EasyDMA MAXCNT register. This
property must be set at SoC level DTS files.

This property is required.

clock-frequency

int

Initial clock frequency in Hz

sq-size

int

Size of the submission queue for blocking requests

Default value: 4

cq-size

int

Size of the completion queue for blocking requests

Default value: 4

pinctrl-1

phandles

Pin configuration/s for the second state. See pinctrl-0.

pinctrl-2

phandles

Pin configuration/s for the third state. See pinctrl-0.

pinctrl-3

phandles

Pin configuration/s for the fourth state. See pinctrl-0.

pinctrl-4

phandles

Pin configuration/s for the fifth state. See pinctrl-0.

pinctrl-names

string-array

Names for the provided states. The number of names needs to match the
number of states.