atmel,sam0-pinctrl

Vendor: Atmel Corporation

Description

Atmel SAM0 Pinctrl container node

The Atmel SAM0 pin controller is a singleton node responsible for controlling
pin function selection and pin properties. For example, you can use this node
to route SERCOM0 as UART were RX to pin PAD1 and enable the pull-up resistor
on the pin.

The node has the 'pinctrl' node label set in your SoC's devicetree, so you can
modify it like this:

  &pinctrl {
          /* your modifications go here */
  };

All device pin configurations should be placed in child nodes of the 'pinctrl'
node, as shown in this example:

  /** You can put this in places like a <board>-pinctrl.dtsi file in
    * your board directory, or a devicetree overlay in your application.
    */

  /** include pre-defined combinations for the SoC variant used by the board */
  #include <dt-bindings/pinctrl/samr21g-pinctrl.h>

  &pinctrl {
    /* configuration for the usart0 "default" state */
    sercom0_uart_default: sercom0_uart_default {
      /* group 1 */
      group1 {
        /* configure PA6 as USART0 TX and PA8 as USART0 CTS */
        pinmux = <PA5D_SERCOM0_PAD1>, <PA6D_SERCOM0_PAD2>;
      };
      /* group 2 */
      group2 {
        /* configure PA5 as USART0 RX and PA7 as USART0 RTS */
        pinmux = <PA4D_SERCOM0_PAD0>, <PA7D_SERCOM0_PAD3>;
        /* both PA5 and PA7 have pull-up enabled */
        bias-pull-up;
      };
    };
  };

The 'usart0_default' child node encodes the pin configurations for a
particular state of a device; in this case, the default (that is, active)
state.

As shown, pin configurations are organized in groups within each child node.
Each group can specify a list of pin function selections in the 'pinmux'
property.

A group can also specify shared pin properties common to all the specified
pins, such as the 'bias-pull-up' property in group 2. Here is a list of
supported standard pin properties:

- bias-pull-up: Enable pull-up resistor.
- bias-pull-down: Enable pull-down resistor.
- drive-strength: Increase sink current.
- input-enable: Enable input on pin.
- output-enable: Enable output on a pin without actively driving it.

To link pin configurations with a device, use a pinctrl-N property for some
number N, like this example you could place in your board's DTS file:

  #include "board-pinctrl.dtsi"

  &usart0 {
        pinctrl-0 = <&usart0_default>;
        pinctrl-names = "default";
  };

Properties

Top level properties

These property descriptions apply to “atmel,sam0-pinctrl” nodes themselves. This page also describes child node properties in the following sections.

Node specific properties

Properties not inherited from the base binding file.

(None)

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 “atmel,sam0-pinctrl” compatible.

Name

Type

Details

#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.

This property is required.

Constant value: 1

#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.

This property is required.

Constant value: 1

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: 'ok', '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

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.

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.

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

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.

Grandchild node properties

Name

Type

Details

pinmux

array

 
An array of pins sharing the same group properties. The pins should
be defined using pre-defined macros or, alternatively, using the
SAM_PINMUX utility macros depending on the pinmux model used by the
SoC series.

This property is required.

drive-strength

int

 
The drive strength controls the output driver strength of an I/O pin
configured as an output.
  0: Pin drive strength is set to normal drive strength.
  1: Pin drive strength is set to stronger drive strength.

Legal values: 0, 1

bias-pull-up

boolean

 
enable pull-up resistor

bias-pull-down

boolean

 
enable pull-down resistor

input-enable

boolean

 
enable input on pin (e.g. enable an input buffer, no effect on output)

output-enable

boolean

 
enable output on a pin without actively driving it (e.g. enable an output
buffer)