atmel,at24 (on i2c bus)

Vendor: Atmel Corporation

Note

An implementation of a driver matching this compatible is available in drivers/eeprom/eeprom_at2x_emul.c.

Description

I2C EEPROMs compatible with Atmel's AT24 family

There are multiple vendors manufacturing I2C EEPROMs compatible with the programming model of the
Atmel AT24.

Examples of compatible EEPROM families:
- Microchip AT24xxx
- ST M24xxx

Each of these can be represented by a set of common parameters (EEPROM size, page size, address
width, and timeout) available from the datasheet of the specific EEPROM. The compatible string for
these can list the specific EEPROM vendor and model along with the vendor EEPROM family as long as
the least-specific compatible entry is "atmel,at24".

Example devicetree node describing a ST M24M01 EEPROM on the i2c0 bus:

  &i2c0 {
    status = "okay";
    clock-frequency = <I2C_BITRATE_FAST>;

    eeprom@56 {
      compatible = "st,m24m01", "st,m24xxx", "atmel,at24";
      reg = <0x56>;
      size = <DT_SIZE_K(128)>;
      pagesize = <256>;
      address-width = <16>;
      timeout = <5>;
   };
 };

Properties

Node specific properties

Properties not inherited from the base binding file.

Name

Type

Details

size

int

 
Total EEPROM size in bytes

This property is required.

pagesize

int

 
EEPROM page size in bytes

This property is required.

address-width

int

 
EEPROM address width in bits

This property is required.

timeout

int

 
EEPROM write cycle timeout in milliseconds

This property is required.

wp-gpios

phandle-array

 
GPIO to which the write-protect pin of the chip is connected.

The device will interpret this signal as active-low.

read-only

boolean

 
Disable writes to the EEPROM

supply-gpios

phandle-array

 
GPIO specifier that controls power to the device.

This property should be provided when the device has a dedicated
switch that controls power to the device.  The supply state is
entirely the responsibility of the device driver.

Contrast with vin-supply.

vin-supply

phandle

 
Reference to the regulator that controls power to the device.
The referenced devicetree node must have a regulator compatible.

This property should be provided when device power is supplied
by a shared regulator.  The supply state is dependent on the
request status of all devices fed by the regulator.

Contrast with supply-gpios.  If both properties are provided
then the regulator must be requested before the supply GPIOS is
set to an active state, and the supply GPIOS must be set to an
inactive state before releasing the regulator.

Deprecated node specific properties

Deprecated properties not inherited from the base binding file.

(None)

Base properties

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 “atmel,at24” compatible.

Name

Type

Details

status

string

 
indicates the operational status of a device

Legal values: 'ok', 'okay', 'disabled', 'reserved', 'fail', 'fail-sss'

See Important properties for more information.

compatible

string-array

 
compatible strings

This property is required.

See Important properties for more information.

reg

array

 
register space

This property is required.

See Important properties for more information.

reg-names

string-array

 
name of each register space

interrupts

array

 
interrupts for device

See Important properties for more information.

interrupts-extended

compound

 
extended interrupt specifier for device

interrupt-names

string-array

 
name of each interrupt

interrupt-parent

phandle

 
phandle to interrupt controller node

label

string

 
Human readable string describing the device (used as device_get_binding() argument)

See Important properties for more information.

This property is deprecated.

clocks

phandle-array

 
Clock gate information

clock-names

string-array

 
name of each clock

#address-cells

int

 
number of address cells in reg property

#size-cells

int

 
number of size cells in reg property

dmas

phandle-array

 
DMA channels specifiers

dma-names

string-array

 
Provided names of DMA channel specifiers

io-channels

phandle-array

 
IO channels specifiers

io-channel-names

string-array

 
Provided names of IO channel specifiers

mboxes

phandle-array

 
mailbox / IPM channels specifiers

mbox-names

string-array

 
Provided names of mailbox / IPM channel specifiers

power-domains

phandle-array

 
Power domain specifiers

power-domain-names

string-array

 
Provided names of power domain specifiers

#power-domain-cells

int

 
Number of cells in power-domains property

zephyr,deferred-init

boolean

 
Do not initialize device automatically on boot. Device should be manually
initialized using device_init().

wakeup-source

boolean

 
Property to identify that a device can be used as wake up source.

When this property is provided a specific flag is set into the
device that tells the system that the device is capable of
wake up the system.

Wake up capable devices are disabled (interruptions will not wake up
the system) by default but they can be enabled at runtime if necessary.

zephyr,pm-device-runtime-auto

boolean

 
Automatically configure the device for runtime power management after the
init function runs.

zephyr,disabling-power-states

phandles

 
List of power states that will disable this device power.