microchip,mcp23s17 (on spi bus)

Vendor: Microchip Technology Inc.

Note

An implementation of a driver matching this compatible is available in drivers/gpio/gpio_mcp23sxx.c.

Description

This is a representation of the Microchip MCP23S17 SPI GPIO Expander.

Properties

Top level properties

These property descriptions apply to “microchip,mcp23s17” nodes themselves. This page also describes child node properties in the following sections.

Node specific properties

Properties not inherited from the base binding file.

Name

Type

Details

#gpio-cells

int

 
Number of items to expect in a GPIO specifier

This property is required.

Constant value: 2

int-gpios

phandle-array

 
GPIO connected to the controller INT pin. This pin is active-low.

reset-gpios

phandle-array

 
GPIO connected to the controller RESET pin. This pin is active-low.

gpio-controller

boolean

 
Convey's this node is a GPIO controller

This property is required.

ngpios

int

 
This property indicates the number of in-use slots of available slots
for GPIOs. The typical example is something like this: the hardware
register is 32 bits wide, but only 18 of the bits have a physical
counterpart. The driver is generally written so that all 32 bits can
be used, but the IP block is reused in a lot of designs, some using
all 32 bits, some using 18 and some using 12. In this case, setting
"ngpios = <18>;" informs the driver that only the first 18 GPIOs, at
local offset 0 .. 17, are in use.  For cases in which there might be
holes in the slot range, this value should be the max slot number+1.

Default value: 32

gpio-reserved-ranges

array

 
If not all the GPIOs at offsets 0...N-1 are usable for ngpios = <N>, then
this property contains an additional set of tuples which specify which GPIOs
are unusable. This property indicates the start and size of the GPIOs
that can't be used.

For example, setting "gpio-reserved-ranges = <3 2>, <10 1>;" means that
GPIO offsets 3, 4, and 10 are not usable, even if ngpios = <18>.

gpio-line-names

string-array

 
This is an array of strings defining the names of the GPIO lines
going out of the GPIO controller

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.

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 “microchip,mcp23s17” compatible.

Name

Type

Details

reg

array

 
register space

This property is required.

See Important properties for more information.

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-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.

Child node properties

Name

Type

Details

gpio-hog

boolean

 
Conveys this node is a GPIO hog.

This property is required.

gpios

array

 
This is an array of GPIO specifiers (e.g. pin, flags) to be hogged. The number of array
entries must be an integer multiple of the number of GPIO specifier cells for the parent
GPIO controller.

This property is required.

input

boolean

 
If this property is set, the GPIO is configured as an input. This property takes
precedence over the output-low and output-high properties.

output-low

boolean

 
If this property is set, the GPIO is configured as an output set to logical low. This
property takes precedence over the output-high property.

output-high

boolean

 
If this property is set, the GPIO is configured as an output set to logical high.

line-name

string

 
Optional GPIO line name.

Specifier cell names

  • gpio cells: pin, flags