The latest development version of this page may be more current than this released 3.7.0 version.

atmel,at45 (on spi bus)

Vendor: Atmel Corporation

Description

Atmel AT45 (or compatible) SPI flash

Properties

Properties not inherited from the base binding file.

Name

Type

Details

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.

spi-max-frequency

int

Maximum clock frequency of device's SPI interface in Hz

This property is required.

duplex

int

Duplex mode, full or half. By default it's always full duplex thus 0
as this is, by far, the most common mode.
Use the macros not the actual enum value, here is the concordance
list (see dt-bindings/spi/spi.h)
  0    SPI_FULL_DUPLEX
  2048 SPI_HALF_DUPLEX

Legal values: 0, 2048

frame-format

int

Motorola or TI frame format. By default it's always Motorola's,
thus 0 as this is, by far, the most common format.
Use the macros not the actual enum value, here is the concordance
list (see dt-bindings/spi/spi.h)
  0     SPI_FRAME_FORMAT_MOTOROLA
  32768 SPI_FRAME_FORMAT_TI

Legal values: 0, 32768

spi-cpol

boolean

SPI clock polarity which indicates the clock idle state.
If it is used, the clock idle state is logic high; otherwise, low.

spi-cpha

boolean

SPI clock phase that indicates on which edge data is sampled.
If it is used, data is sampled on the second edge; otherwise, on the first edge.

spi-hold-cs

boolean

In some cases, it is necessary for the master to manage SPI chip select
under software control, so that multiple spi transactions can be performed
without releasing it. A typical use case is variable length SPI packets
where the first spi transaction reads the length and the second spi transaction
reads length bytes.

jedec-id

uint8-array

JEDEC ID as manufacturer ID (1 byte) and device ID (2 bytes).

This property is required.

size

int

Flash capacity in bits.

This property is required.

sector-size

int

Flash sector size in bytes.

This property is required.

sector-0a-pages

int

Most available AT45 flash chips have their first two sectors shorter
than the consecutive ones. Usually, the first sector is marked as 0a
and has its size equal to eight pages (one block) and the second one
(usually 0b) is the complement to the size of a regular sector.
This property allows specifying the size (in pages) of that first sector
and defaults to the commonly used value of eight pages.
Value of zero means that the flash chip has all sectors of equal size.

Default value: 8

block-size

int

Flash block size in bytes.

This property is required.

page-size

int

Flash page size in bytes.

This property is required.

no-chip-erase

boolean

If set, indicates that the chip does not support the chip erase command.

no-sector-erase

boolean

If set, indicates that the chip does not support the sector erase command.

use-udpd

boolean

When set, the driver will use the Ultra-Deep Power-Down command instead
of the default Deep Power-Down one to put the chip into low power mode.

From the driver perspective, as it does not rely on the contents of the
SRAM buffers in the chip, the difference between the Deep and Ultra-Deep
Power-Down modes is that the chip consumes far less power in the latter
but needs some more time to enter this mode and to exit from it.

enter-dpd-delay

int

Time, in nanoseconds, needed by the chip to enter the Deep Power-Down
mode (or Ultra-Deep Power-Down mode when the "use-udpd" property is set)
after the corresponding command is issued.

exit-dpd-delay

int

Time, in nanoseconds, needed by the chip to exit from the Deep Power-Down
mode (or Ultra-Deep Power-Down mode when the "use-udpd" property is set)
after the corresponding command is issued.

reset-gpios

phandle-array

The RESET pin of AT45 is active low.
If connected directly the MCU pin should be configured
as active low.

wp-gpios

phandle-array

The WP pin of AT45 is active low.
If connected directly the MCU pin should be configured
as active low.