new file mode 100644
@@ -0,0 +1,176 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/pinctrl/thead,th1520-pinctrl.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: T-Head TH1520 SoC pin controller
+
+maintainers:
+ - Emil Renner Berthing <emil.renner.berthing@canonical.com>
+
+description: |
+ Pinmux and pinconf controller in the T-Head TH1520 RISC-V SoC.
+
+ The TH1520 has 3 groups of pads each controlled from different memory ranges.
+ Confusingly the memory ranges are named
+ PADCTRL_AOSYS -> PAD Group 1
+ PADCTRL1_APSYS -> PAD Group 2
+ PADCTRL0_APSYS -> PAD Group 3
+
+ Each pad can be muxed individually to up to 6 different functions. For most
+ pads only a few of those 6 configurations are valid though, and a few pads in
+ group 1 does not support muxing at all.
+
+ Pinconf is fairly regular except for a few pads in group 1 that either can't
+ be configured or has some special functions. The rest have configurable drive
+ strength, input enable, schmitt trigger, slew rate, pull-up and pull-down in
+ addition to a special strong pull up.
+
+ Certain pads in group 1 can be muxed to AUDIO_PA0 - AUDIO_PA30 functions and
+ are then meant to be used by the audio co-processor. Each such pad can then
+ be further muxed to either audio GPIO or one of 4 functions such as UART, I2C
+ and I2S. If the audio pad is muxed to one of the 4 functions then pinconf is
+ also configured in different registers. All of this is done from a different
+ AUDIO_IOCTRL memory range and is left to the audio co-processor for now.
+
+properties:
+ compatible:
+ enum:
+ - thead,th1520-pinctrl
+ reg:
+ maxItems: 1
+
+ clocks:
+ maxItems: 1
+
+ thead,pad-group:
+ description: |
+ Select the pad group that is associated with the pin controller instance.
+
+ Base Address Name Group
+ 0xFF_FFF4_A000 PADCTRL_AOSYS 1
+ 0xFF_E7F3_C000 PADCTRL1_APSYS 2
+ 0xFF_EC00_7000 PADCTRL0_APSYS 3
+
+ $ref: /schemas/types.yaml#/definitions/uint32
+ enum: [1, 2, 3]
+
+required:
+ - compatible
+ - reg
+ - clocks
+
+patternProperties:
+ '-[0-9]+$':
+ type: object
+ additionalProperties: false
+
+ patternProperties:
+ '-pins$':
+ type: object
+ allOf:
+ - $ref: /schemas/pinctrl/pincfg-node.yaml#
+ - $ref: /schemas/pinctrl/pinmux-node.yaml#
+
+ additionalProperties: false
+
+ description:
+ A pinctrl node should contain at least one subnode describing one
+ or more pads and their associated pinmux and pinconf settings.
+
+ properties:
+ pins:
+ description: List of pads that properties in the node apply to.
+
+ function:
+ enum: [ gpio, pwm, uart, ir, i2c, spi, qspi, sdio, audio, i2s,
+ gmac0, gmac1, dpu0, dpu1, isp, hdmi, bootsel, debug,
+ clock, jtag, iso7816, efuse, reset ]
+ description: The mux function to select for the given pins.
+
+ bias-disable: true
+
+ bias-pull-up:
+ oneOf:
+ - type: boolean
+ description: Enable the regular 48kOhm pull-up
+ - enum: [ 2100, 48000 ]
+ description: Enable the strong 2.1kOhm pull-up or regular 48kOhm pull-up
+
+ bias-pull-down:
+ oneOf:
+ - type: boolean
+ - const: 44000
+ description: Enable the regular 44kOhm pull-down
+
+ drive-strength:
+ enum: [ 1, 2, 3, 5, 7, 8, 10, 12, 13, 15, 16, 18, 20, 21, 23, 25 ]
+ description: Drive strength in mA
+
+ input-enable: true
+
+ input-disable: true
+
+ input-schmitt-enable: true
+
+ input-schmitt-disable: true
+
+ slew-rate:
+ maximum: 1
+
+ required:
+ - pins
+
+additionalProperties: false
+
+examples:
+ - |
+ padctrl0_apsys: pinctrl@ec007000 {
+ compatible = "thead,th1520-pinctrl";
+ reg = <0xec007000 0x1000>;
+ clocks = <&apb_clk>;
+ thead,pad-group = <3>;
+
+ uart0_pins: uart0-0 {
+ tx-pins {
+ pins = "UART0_TXD";
+ function = "uart";
+ bias-disable;
+ drive-strength = <3>;
+ input-disable;
+ input-schmitt-disable;
+ slew-rate = <0>;
+ };
+
+ rx-pins {
+ pins = "UART0_RXD";
+ function = "uart";
+ bias-disable;
+ drive-strength = <1>;
+ input-enable;
+ input-schmitt-enable;
+ slew-rate = <0>;
+ };
+ };
+ };
+
+ padctrl1_apsys: pinctrl@e7f3c000 {
+ compatible = "thead,th1520-pinctrl";
+ reg = <0xe7f3c000 0x1000>;
+ clocks = <&apb_clk>;
+ thead,pad-group = <2>;
+
+ i2c5_pins: i2c5-0 {
+ i2c-pins {
+ pins = "QSPI1_CSN0", /* I2C5_SCL */
+ "QSPI1_D0_MOSI"; /* I2C5_SDA */
+ function = "i2c";
+ bias-pull-up = <2100>;
+ drive-strength = <7>;
+ input-enable;
+ input-schmitt-enable;
+ slew-rate = <0>;
+ };
+ };
+ };
@@ -19942,6 +19942,7 @@ L: linux-riscv@lists.infradead.org
S: Maintained
T: git https://github.com/pdp7/linux.git
F: Documentation/devicetree/bindings/clock/thead,th1520-clk-ap.yaml
+F: Documentation/devicetree/bindings/pinctrl/thead,th1520-pinctrl.yaml
F: arch/riscv/boot/dts/thead/
F: drivers/clk/thead/clk-th1520-ap.c
F: include/dt-bindings/clock/thead,th1520-clk-ap.h