nordic,nrf-sw-pwm

Vendor: Nordic Semiconductor

Note

An implementation of a driver matching this compatible is available in drivers/pwm/pwm_nrf_sw.c.

Description

nRFx S/W PWM

Properties

Node specific properties

Properties not inherited from the base binding file.

Name

Type

Details

generator

phandle

 
Reference to TIMER or RTC instance for generating PWM output signals

This property is required.

clock-prescaler

int

 
Clock prescaler for RTC or TIMER used for generating PWM output signals.

RTC: needs to be set to 0, which gives 32768 Hz base clock for PWM
generation.

TIMER: 16 MHz / 2^prescaler base clock is used for PWM generation.

This property is required.

channel-gpios

phandle-array

 
An array of GPIOs assigned as outputs for the PWM channels. The number
of items in this array determines the number of channels that this PWM
will provide. This value is limited by the number of compare registers
in the used RTC/TIMER instance minus 1.

Example:

  sw_pwm: sw-pwm {
    compatible = "nordic,nrf-sw-pwm";
    ...
    channel-gpios = <&gpio0 20 GPIO_ACTIVE_HIGH>,
                    <&gpio1 12 GPIO_ACTIVE_HIGH>;
    ...
  };

The above will assign P0.20 as the output for channel 0 and P1.12 as
the output for channel 1. Both outputs will be initially configured as
active high.

Please note that in the flags cell (the last component of each item
of the array) only the GPIO flags that specify the active level are
taken into account (any others are ignored), and they are used only
when the initial (inactive) state of the outputs is set.
After any PWM signal generation is requested for a given channel,
the polarity of its output is determined by the flag specified
in the request, i.e. PWM_POLARITY_INVERTED or PWM_POLARITY_NORMAL.

This property is required.

#pwm-cells

int

 
Number of items to expect in a pwm specifier

This property is required.

Constant value: 3

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 “nordic,nrf-sw-pwm” 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

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

 
No description provided for this label

See Important properties for more information.

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.

Specifier cell names

  • pwm cells: channel, period, flags