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 |
---|---|---|
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The SDA pin to use.
For pins P0.0 through P0.31, use the pin number. For example,
to use P0.16 for SDA, set:
sda-pin = <16>;
For pins P1.0 through P1.31, add 32 to the pin number. For
example, to use P1.2 for SDA, set:
sda-pin = <34>; /* 32 + 2 */
This property is required. |
|
|
The SCL pin to use. The pin numbering scheme is the same as
the sda-pin property's.
This property is required. |
|
|
Initial clock frequency in Hz
|
Properties inherited from the base binding file, which defines common properties that may be set on many nodes. Not all of these may apply to the “nordic,nrf-twi” compatible.
Name |
Type |
Details |
---|---|---|
|
|
register space
This property is required. See Important properties for more information. |
|
|
interrupts for device
This property is required. See Important properties for more information. |
|
|
number of address cells in reg property
This property is required. Constant value: |
|
|
number of size cells in reg property
This property is required. |
|
|
Human readable string describing the device (used as device_get_binding() argument)
This property is required. See Important properties for more information. |
|
|
indicates the operational status of a device
Legal values: See Important properties for more information. |
|
|
compatible strings
This property is required. See Important properties for more information. |
|
|
name of each register space
|
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|
extended interrupt specifier for device
|
|
|
name of each interrupt
|
|
|
phandle to interrupt controller node
|
|
|
Clock gate information
|
|
|
name of each clock
|
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|
DMA channels specifiers
|
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|
Provided names of DMA channel specifiers
|
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IO channels specifiers
|
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Provided names of IO channel specifiers
|