zephyr/dts/bindings/pinctrl/nxp,imx7d-pinctrl.yaml

95 lines
2.8 KiB
YAML

# Copyright (c) 2022 NXP
# SPDX-License-Identifier: Apache-2.0
description: |
The node has the 'pinctrl' node label set in MCUX SoC's devicetree. These
nodes can be autogenerated using the MCUXpresso config tools combined with
the imx_dts_gen.py script in NXP's HAL. The mux, mode, input, daisy, and cfg
fields in a group select the pins to be configured, and the remaining
devicetree properties set configuration values for those pins
Note that the soc level iomuxc dts file can be examined to find the possible
pinmux options. Here are the affects of each property on the
IOMUXC SW_PAD_CTL register:
bias-pull-up: PE=1, PS=<bias-pull-up-value index>
bias-pull-down: PE=1, PS=0
input-schmitt-enable: HYS=1
slew-rate: SRE=<enum idx>
drive-strength: DSE=<enum idx>
input-enable: SION=1 (in SW_PAD_CTL_MUX register)
If only required properties are supplied, the pin will have the following
configuration:
HYS=0,
PS=0,
PE=0
SRE=<slew-rate>,
DSE=<drive-strength>,
SION=0,
Note that pins marked with LPSR can only have their PE and PS registers
configured
compatible: "nxp,imx7d-pinctrl"
include:
- name: base.yaml
- name: pincfg-node-group.yaml
child-binding:
child-binding:
property-allowlist:
- input-schmitt-enable
- input-enable
- bias-pull-up
- bias-pull-down
child-binding:
description: iMX pin controller pin group
child-binding:
description: |
iMX pin controller pin configuration node.
properties:
pinmux:
required: true
type: phandles
description: |
Pin mux selections for this group. See the soc level iomuxc DTSI file
for a defined list of these options.
drive-strength:
required: true
type: string
enum:
- "x1"
- "x4"
- "x2"
- "x6"
description: |
Pin output drive strength. Sets the DSE field in the IOMUXC peripheral.
slew-rate:
required: true
type: string
enum:
- "fast"
- "slow"
description: |
Select slew rate for pin. Corresponds to SRE field in IOMUXC peripheral
0 FAST — Fast Frequency Slew Rate
1 SLOW — Slow Frequency Slew Rate
bias-pull-up-value:
required: false
type: string
default: "100k"
enum:
- "unused"
- "5k"
- "47k"
- "100k"
description: |
Select pull up resistor value. Sets PS field in IOMUXC peripheral.
Default of 100k as this is most common default register value for
SOC pads.
01: 5K- 5K pull up resistor
10: 47K- 47K pull up resistor
11: 100K- 100K pull up resistor