# Copyright (c) 2023 Antmicro # SPDX-License-Identifier: Apache-2.0 description: | The Ambiq Apollo4 pin controller is a node responsible for controlling pin function selection and pin properties, such as routing a UART0 TX to pin 60 and enabling the pullup resistor on that 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 &pinctrl { uart0_default: uart0_default { group1 { pinmux = ; }; group2 { pinmux = ; input-enable; }; }; }; The 'uart0_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 'input-enable' property in group 2. compatible: "ambiq,apollo4-pinctrl" include: base.yaml child-binding: description: | Definitions for a pinctrl state. child-binding: include: - name: pincfg-node.yaml property-allowlist: - input-enable - drive-push-pull - drive-open-drain - bias-high-impedance - bias-pull-up - bias-pull-down properties: pinmux: required: true type: array description: | An array of pins sharing the same group properties. Each element of the array is an integer constructed from the pin number and the alternative function of the pin. drive-strength: type: string enum: - "0.1" - "0.5" - "0.75" - "1.0" default: "0.1" description: | The drive strength of a pin, relative to full-driver strength. The default value is 0.1, which is the reset value. slew-rate: type: string enum: - "slow" - "fast" default: "slow" description: | Select slew rate for a pin. The default is slow, which is the reset value. ambiq,pull-up-ohms: type: int enum: - 1500 - 6000 - 12000 - 24000 - 50000 - 100000 default: 1500 description: | The pullup resistor value. The default value is 1500 ohms. ambiq,iom-nce-module: type: int default: 0 description: | IOM nCE module select, selects the SPI channel (CE) number (0-42). 0, IOM0CE0 : IOM 0 NCE 0 module 1, IOM0CE1 : IOM 0 NCE 1 module 2, IOM0CE2 : IOM 0 NCE 2 module 3, IOM0CE3 : IOM 0 NCE 3 module 4, IOM1CE0 : IOM 1 NCE 0 module 5, IOM1CE1 : IOM 1 NCE 1 module 6, IOM1CE2 : IOM 1 NCE 2 module 7, IOM1CE3 : IOM 1 NCE 3 module 8, IOM2CE0 : IOM 2 NCE 0 module 9, IOM2CE1 : IOM 2 NCE 1 module 10, IOM2CE2 : IOM 2 NCE 2 module 11, IOM2CE3 : IOM 2 NCE 3 module 12, IOM3CE0 : IOM 3 NCE 0 module 13, IOM3CE1 : IOM 3 NCE 1 module 14, IOM3CE2 : IOM 3 NCE 2 module 15, IOM3CE3 : IOM 3 NCE 3 module 16, IOM4CE0 : IOM 4 NCE 0 module 17, IOM4CE1 : IOM 4 NCE 1 module 18, IOM4CE2 : IOM 4 NCE 2 module 19, IOM4CE3 : IOM 4 NCE 3 module 20, IOM5CE0 : IOM 5 NCE 0 module 21, IOM5CE1 : IOM 5 NCE 1 module 22, IOM5CE2 : IOM 5 NCE 2 module 23, IOM5CE3 : IOM 5 NCE 3 module 24, IOM6CE0 : IOM 6 NCE 0 module 25, IOM6CE1 : IOM 6 NCE 1 module 26, IOM6CE2 : IOM 6 NCE 2 module 27, IOM6CE3 : IOM 6 NCE 3 module 28, IOM7CE0 : IOM 7 NCE 0 module 29, IOM7CE1 : IOM 7 NCE 1 module 30, IOM7CE2 : IOM 7 NCE 2 module 31, IOM7CE3 : IOM 7 NCE 3 module 32, MSPI0CEN0 : MSPI 0 NCE 0 module 33, MSPI0CEN1 : MSPI 0 NCE 1 module 34, MSPI1CEN0 : MSPI 1 NCE 0 module 35, MSPI1CEN1 : MSPI 1 NCE 1 module 36, MSPI2CEN0 : MSPI 2 NCE 0 module 37, MSPI2CEN1 : MSPI 2 NCE 1 module 38, DC_DPI_DE : DC DPI DE module 39, DISP_CONT_CSX : DISP CONT CSX module 40, DC_SPI_CS_N : DC SPI CS_N module 41, DC_QSPI_CS_N : DC QSPI CS_N module 42, DC_RESX : DC module RESX If the pin is not a CE, this descriptor will be ignored. Default value 0, which is the reset value. ambiq,iom-mspi: type: int default: 0 description: | Indicates the module which uses specific CE pin, 1 if CE is IOM, 0 if MSPI. Default value 0, which is the reset value. If the pin is not a CE, this descriptor will be ignored. ambiq,iom-num: type: int default: 0 description: | Indicates the instance which uses specific CE pin. IOM number (0-7) or MSPI (0-2). Default value 0, which is the reset value. If the pin is not a CE, this descriptor will be ignored. ambiq,interrupt-direction: type: int default: 0 description: | Indicates the pininterrupt direction. Default value 0, which is the reset value.