| # SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) |
| %YAML 1.2 |
| --- |
| $id: http://devicetree.org/schemas/nvmem/nvmem.yaml# |
| $schema: http://devicetree.org/meta-schemas/core.yaml# |
| |
| title: NVMEM (Non Volatile Memory) Device Tree Bindings |
| |
| maintainers: |
| - Srinivas Kandagatla <srinivas.kandagatla@linaro.org> |
| |
| description: | |
| This binding is intended to represent the location of hardware |
| configuration data stored in NVMEMs like eeprom, efuses and so on. |
| |
| On a significant proportion of boards, the manufacturer has stored |
| some data on NVMEM, for the OS to be able to retrieve these |
| information and act upon it. Obviously, the OS has to know about |
| where to retrieve these data from, and where they are stored on the |
| storage device. |
| |
| properties: |
| $nodename: |
| pattern: "^(eeprom|efuse|nvram)(@.*|-[0-9a-f])*$" |
| |
| "#address-cells": |
| const: 1 |
| |
| "#size-cells": |
| const: 1 |
| |
| read-only: |
| $ref: /schemas/types.yaml#/definitions/flag |
| description: |
| Mark the provider as read only. |
| |
| wp-gpios: |
| description: |
| GPIO to which the write-protect pin of the chip is connected. |
| The write-protect GPIO is asserted, when it's driven high |
| (logical '1') to block the write operation. It's deasserted, |
| when it's driven low (logical '0') to allow writing. |
| maxItems: 1 |
| |
| patternProperties: |
| "^.*@[0-9a-f]+$": |
| type: object |
| |
| properties: |
| reg: |
| maxItems: 1 |
| description: |
| Offset and size in bytes within the storage device. |
| |
| bits: |
| maxItems: 1 |
| items: |
| items: |
| - minimum: 0 |
| maximum: 7 |
| description: |
| Offset in bit within the address range specified by reg. |
| - minimum: 1 |
| description: |
| Size in bit within the address range specified by reg. |
| |
| required: |
| - reg |
| |
| additionalProperties: true |
| |
| examples: |
| - | |
| #include <dt-bindings/gpio/gpio.h> |
| |
| qfprom: eeprom@700000 { |
| #address-cells = <1>; |
| #size-cells = <1>; |
| reg = <0x00700000 0x100000>; |
| |
| wp-gpios = <&gpio1 3 GPIO_ACTIVE_HIGH>; |
| |
| /* ... */ |
| |
| /* Data cells */ |
| tsens_calibration: calib@404 { |
| reg = <0x404 0x10>; |
| }; |
| |
| tsens_calibration_bckp: calib_bckp@504 { |
| reg = <0x504 0x11>; |
| bits = <6 128>; |
| }; |
| |
| pvs_version: pvs-version@6 { |
| reg = <0x6 0x2>; |
| bits = <7 2>; |
| }; |
| |
| speed_bin: speed-bin@c{ |
| reg = <0xc 0x1>; |
| bits = <2 3>; |
| }; |
| }; |
| |
| ... |
