renesas,ra-lvd

Description

Renesas RA LVD (Low-voltage detection) Controller

The following example displays the minimum node layout:

  lvd1: lvd@4001e0e0 {
          compatible = "renesas,ra-lvd";
          reg = <0x4001e0e0 0x02>;
          channel = <1>;
          status = "disabled";
  };

Enabling the comparator controller node requires setting the minimum
default configuration of the comparator. This includes selecting the
positive and negative inputs.
Note: negative input of this controller is selected through specific
voltage threshold levels, and positive input is Vcc

  &lvd1 {
        lvd-action = "maskable-interrupt";
        voltage_level = <384>;
        lvd-trigger = "rising";
        reset-negation-timing = <0>;
        status = "okay";
  };

Properties

Node specific properties

Properties not inherited from the base binding file.

Name

Type

Details

channel

int

This property is required.

voltage-level

int

Specifies the voltage detection level for each channel.
This value can be mapped to voltage level that is shown in the HWM.
Example:
  On RA8P1:
  - To set the voltage detection level to 3.86 V, specify '0x03'.
  - To set the voltage detection level to 1.90 V, specify '0x0C'.
  ...
Note:
  - Do not set to a value that is prohibited in the HWM.
For specific voltage detection support levels of each RA MCU series,
please refer to the HWM.

This property is required.

noise-filter

int

Select the LOCO divisor for the hardware digital debounce filter.
Larger divisors provide a longer debounce and take longer for the output to update.
Set to 1 to disable the filter (or if the filter is not supported).

Default value: 16

Legal values: 1, 2, 4, 8, 16

lvd-trigger

string

Specifies the voltage detection conditions and influences interrupt conditions.

Default value: falling

Legal values: 'rising', 'falling', 'both'

reset-only

boolean

This property indicate that the channel only support the reset action
(no interrupt and monitoring).

lvd-action

string

Choose the action to be taken when the LVD is detected.
If "reset-only" properties is true, action will always be "reset".

This property is required.

Legal values: 'non-maskable-interrupt', 'maskable-interrupt', 'reset', 'no-action'

reset-negation-timing

int

Specifies the time when the system release (negate) from reset
When action is "reset", trigger is "falling" (system reset when Vcc < Vdet):
  - 0: Reset negation occurs after Vcc > Vdet + stabilization time.
  - 1: Reset negation occurs after assertion of the reset + stabilization time.
When action is "reset", trigger is "rising" (system reset when Vcc > Vdet):
  - 0: Reset negation occurs after Vcc < Vdet - stabilization time.
  - 1: DO NOT set this value.
When action is other than "reset", this property is ignored.

Legal values: 0, 1

pinctrl-0

phandles

Pin configuration/s for the first state. Content is specific to the
selected pin controller driver implementation.

pinctrl-1

phandles

Pin configuration/s for the second state. See pinctrl-0.

pinctrl-2

phandles

Pin configuration/s for the third state. See pinctrl-0.

pinctrl-3

phandles

Pin configuration/s for the fourth state. See pinctrl-0.

pinctrl-4

phandles

Pin configuration/s for the fifth state. See pinctrl-0.

pinctrl-names

string-array

Names for the provided states. The number of names needs to match the
number of states.

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 “renesas,ra-lvd” compatible.

Name

Type

Details

reg

array

Information used to address the device. The value is specific to
the device (i.e. is different depending on the compatible
property).

The "reg" property is typically a sequence of (address, length) pairs.
Each pair is called a "register block". Values are
conventionally written in hex.

For details, see "2.3.6 reg" in Devicetree Specification v0.4.

This property is required.

See Important properties for more information.

status

string

Indicates the operational status of the hardware or other
resource that the node represents. In particular:

  - "okay" means the resource is operational and, for example,
    can be used by device drivers
  - "disabled" means the resource is not operational and the system
    should treat it as if it is not present

For details, see "2.3.4 status" in Devicetree Specification v0.4.

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

See Important properties for more information.

compatible

string-array

This property is a list of strings that essentially define what
type of hardware or other resource this devicetree node
represents. Each device driver checks for specific compatible
property values to find the devicetree nodes that represent
resources that the driver should manage.

The recommended format is "vendor,device", The "vendor" part is
an abbreviated name of the vendor. The "device" is usually from
the datasheet.

The compatible property can have multiple values, ordered from
most- to least-specific. Having additional values is useful when the
device is a specific instance of a more general family, to allow the
system to match the most specific driver available.

For details, see "2.3.1 compatible" in Devicetree Specification v0.4.

This property is required.

See Important properties for more information.

reg-names

string-array

Optional names given to each register block in the "reg" property.
For example:

  / {
       soc {
           #address-cells = <1>;
           #size-cells = <1>;

           uart@1000 {
               reg = <0x1000 0x2000>, <0x3000 0x4000>;
               reg-names = "foo", "bar";
           };
       };
  };

The uart@1000 node has two register blocks:

  - one with base address 0x1000, size 0x2000, and name "foo"
  - another with base address 0x3000, size 0x4000, and name "bar"

interrupts

array

Information about interrupts generated by the device, encoded as an array
of one or more interrupt specifiers. The format of the data in this property
varies by where the device appears in the interrupt tree. Devices with the same
"interrupt-parent" will use the same format in their interrupts properties.

For details, see "2.4 Interrupts and Interrupt Mapping" in
Devicetree Specification v0.4.

See Important properties for more information.

interrupts-extended

compound

Extended interrupt specifier for device, used as an alternative to
the "interrupts" property.

For details, see "2.4 Interrupts and Interrupt Mapping" in
Devicetree Specification v0.4.

interrupt-names

string-array

Optional names given to each interrupt generated by a device.
The interrupts themselves are defined in either "interrupts" or
"interrupts-extended" properties.

For details, see "2.4 Interrupts and Interrupt Mapping" in
Devicetree Specification v0.4.

interrupt-parent

phandle

If present, this refers to the node which handles interrupts generated
by this device.

For details, see "2.4 Interrupts and Interrupt Mapping" in
Devicetree Specification v0.4.

label

string

Human readable string describing the device. Use of this property is
deprecated except as needed on a case-by-case basis.

For details, see "4.1.2 Miscellaneous Properties" in Devicetree
Specification v0.4.

See Important properties for more information.

clocks

phandle-array

Information about the device's clock providers. In general, this property
should follow conventions established in the dt-schema binding:

  https://github.com/devicetree-org/dt-schema/blob/main/dtschema/schemas/clock/clock.yaml

clock-names

string-array

Optional names given to each clock provider in the "clocks" property.

#address-cells

int

This property encodes the number of <u32> cells used by address fields
in "reg" properties in this node's children.

For details, see "2.3.5 #address-cells and #size-cells" in Devicetree
Specification v0.4.

#size-cells

int

This property encodes the number of <u32> cells used by size fields in
"reg" properties in this node's children.

For details, see "2.3.5 #address-cells and #size-cells" in Devicetree
Specification v0.4.

dmas

phandle-array

DMA channel specifiers relevant to the device.

dma-names

string-array

Optional names given to the DMA channel specifiers in the "dmas" property.

io-channels

phandle-array

IO channel specifiers relevant to the device.

io-channel-names

string-array

Optional names given to the IO channel specifiers in the "io-channels" property.

mboxes

phandle-array

Mailbox / IPM channel specifiers relevant to the device.

mbox-names

string-array

Optional names given to the mbox specifiers in the "mboxes" property.

power-domains

phandle-array

Power domain specifiers relevant to the device.

power-domain-names

string-array

Optional names given to the power domain specifiers in the "power-domains" property.

#power-domain-cells

int

Number of cells in power-domains property

hwlocks

phandle-array

HW spinlock id relevant to the device.

hwlock-names

string-array

Optional names given to the hwlock specifiers in the "hwlocks" 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.