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.
Properties not inherited from the base binding file.
(None)
Deprecated properties not inherited from the base binding file.
(None)
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 |
|---|---|---|
|
|
number of address cells in reg property
This property is required. Constant value: |
|
|
number of size cells in reg property
This property is required. Constant value: |
|
|
indicates the operational status of a device
Legal values: See Important properties for more information. |
|
|
compatible strings
This property is required. See Important properties for more information. |
|
|
register space
See Important properties for more information. |
|
|
name of each register space
|
|
|
interrupts for device
See Important properties for more information. |
|
|
extended interrupt specifier for device
|
|
|
name of each interrupt
|
|
|
phandle to interrupt controller node
|
|
|
Human readable string describing the device (used as device_get_binding() argument)
See Important properties for more information. This property is deprecated. |
|
|
Clock gate information
|
|
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name of each clock
|
|
|
DMA channels specifiers
|
|
|
Provided names of DMA channel specifiers
|
|
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IO channels specifiers
|
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|
Provided names of IO channel specifiers
|
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mailbox / IPM channels specifiers
|
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Provided names of mailbox / IPM channel specifiers
|
|
|
Power domain specifiers
|
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|
Provided names of power domain specifiers
|
|
|
Number of cells in power-domains property
|
|
|
Do not initialize device automatically on boot. Device should be manually
initialized using device_init().
|
|
|
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.
|
|
|
Automatically configure the device for runtime power management after the
init function runs.
|
|
|
List of power states that will disable this device power.
|
Grandchild node properties
Name |
Type |
Details |
|---|---|---|
|
|
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. |
|
|
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: |
|
|
enable pull-up resistor
|
|
|
enable pull-down resistor
|
|
|
enable input on pin (e.g. enable an input buffer, no effect on output)
|
|
|
enable output on a pin without actively driving it (e.g. enable an output
buffer)
|