ti,fdc2x1x (on i2c bus)

Vendor: Texas Instruments

Note

An implementation of a driver matching this compatible is available in drivers/sensor/ti/fdc2x1x/fdc2x1x.c.

Description

Texas Instruments FDC2X1X capacitive sensor

Properties

Top level properties

These property descriptions apply to “ti,fdc2x1x” 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

sd-gpios

phandle-array

The SD pin defaults to active high when consumed by the sensor.
The property value should ensure the flags properly describe
the signal that is presented to the driver.

intb-gpios

phandle-array

The INTB pin defaults to active low when produced by the sensor.
The property value should ensure the flags properly describe
the signal that is presented to the driver.

fdc2x14

boolean

Set to identify the sensor as FDC2114 or FDC2214 (4-channel version)

autoscan

boolean

Set the Auto-Scan Mode.

false = Continuous conversion on the single channel selected by
"active-channel" (single channel mode).

true = Auto-Scan conversions as selected by "rr-sequence"
(multichannel mode).

fref

int

Reference frequency of the used clock source in KHz.
The internal clock oscillates at around 43360 KHz (43.36 MHz)
at 20 degrees Celsius.
Recommended external clock source frequency is 40000 KHz (40 MHz).

This property is required.

rr-sequence

int

Auto-Scan Sequence Configuration.
The FDC will perform a single conversion on each channel
in the sequence selected, and then restart the sequence continuously.

The sensor performs conversion on Channel 0 to 1 by default after
power-on-reset. This setting only applies if autoscan=true
(multichannel mode).

0 = Ch0, Ch1
1 = Ch0, Ch1, Ch2 (FDC2114, FDC2214 only)
2 = Ch0, Ch1, Ch2, Ch3 (FDC2114, FDC2214 only)

Legal values: 0, 1, 2

active-channel

int

Selects channel for continuous conversions.

The sensor performs continuous conversion on Channel 0 by default after
power-on-reset. This setting only applies if autoscan=false
(single channel mode).

0 = Perform continuous conversions on Channel 0
1 = Perform continuous conversions on Channel 1
2 = Perform continuous conversions on Channel 2 (FDC2114, FDC2214 only)
3 = Perform continuous conversions on Channel 3 (FDC2114, FDC2214 only)

Legal values: 0, 1, 2, 3

deglitch

int

Input deglitch filter bandwidth. Select the lowest setting that exceeds
the oscillation tank oscillation frequency.

1 = 1MHz
4 = 3.3MHz
5 = 10MHz
7 = 33MHz

This property is required.

Legal values: 1, 4, 5, 7

sensor-activate-sel

string

Sensor Activation Mode Selection.

The sensor uses low-power activation mode by default after
power-on-reset.

full-current = the FDC will drive maximum
sensor current for a shorter sensor activation time.

low-power = the FDC uses the value programmed by "idrive" during
sensor activation to minimize power consumption.

Default value: low-power

Legal values: 'full-current', 'low-power'

ref-clk-src

string

Select Reference Frequency Source.

The sensor uses the internal clock by default after power-on-reset.

internal = Use Internal oscillator as reference frequency
external = Reference frequency is provided from CLKIN pin.

Default value: internal

Legal values: 'internal', 'external'

current-drive

string

Select Current Sensor Drive.

The sensor uses normal current drive by default after power-on-reset.
High current drive is not supported if autoscan=false and will default
to normal.

normal = The FDC will drive all channels with normal sensor current
(1.5mA max).

high = The FDC will drive channel 0 with current >1.5mA.

Default value: normal

Legal values: 'normal', 'high'

output-gain

int

Output gain control (FDC2112, FDC2114 only)

The default output gain is 0 after power-on-reset.

0 = Gain = 1   | Effective Resolution 12 bits | 100% full scale
1 = Gain = 4   | Effective Resolution 14 bits | 25% full scale
2 = Gain = 8   | Effective Resolution 15 bits | 12.5% full scale
3 = Gain = 16  | Effective Resolution 16 bits | 6.25% full scale

Legal values: 0, 1, 2, 3

friendly-name

string

Human readable string describing the sensor. It can be used to
distinguish multiple instances of the same model (e.g., lid accelerometer
vs. base accelerometer in a laptop) to a host operating system.

This property is defined in the Generic Sensor Property Usages of the HID
Usage Tables specification
(https://usb.org/sites/default/files/hut1_3_0.pdf, section 22.5).

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 “ti,fdc2x1x” 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.

Child node properties

Name

Type

Details

rcount

int

Channel X Reference Count Conversion Interval Time.
Valid range: 256 - 65535

This property is required.

offset

int

Channel X Conversion Offset (FDC2112 and FDC2212 only).
The default offset value after power-on-reset is 0.
Valid range: 0 - 65535

settlecount

int

Channel X Conversion Settling.

The FDC will use this settling time to allow the LC sensor to
stabilize before initiation of a conversion on Channel X.
Valid range: 0 - 65535

This property is required.

fref-divider

int

Channel X Reference Divider.

Sets the divider for Channel X reference.
Use this to scale the maximum conversion frequency.
Valid range: 1 - 1023

This property is required.

idrive

int

Channel X Sensor drive current.

This field defines the Drive Current used during the settling +
conversion time of Channel X sensor clock.
Valid range: 0 - 31

This property is required.

fin-sel

int

Channel X Sensor frequency select.

For differential sensor configuration:
1 = divide by 1. Choose for sensor frequencies between
0.01MHz and 8.75MHz
2 = divide by 2. Choose for sensor frequencies between 5MHz
and 10MHz

For single-ended sensor configuration:
2 = divide by 2. Choose for sensor frequencies between
0.01MHz and 10MHz

This property is required.

Legal values: 1, 2

inductance

int

Inductor value used on the PCB for the sensing network of the
specific channel, which is usually 18uH.

This property is required.