Documentation describes the required and optional properties for implementing Device Tree for a Microsoft G6 Touch Digitizer that supports HID over SPI Protocol 1.0 specification.
The properties are common to HID over SPI. Signed-off-by: Dmitry Antipov <[email protected]> Signed-off-by: Jarrett Schultz <[email protected]> Signed-off-by: Jingyuan Liang <[email protected]> --- .../devicetree/bindings/input/hid-over-spi.yaml | 153 +++++++++++++++++++++ 1 file changed, 153 insertions(+) diff --git a/Documentation/devicetree/bindings/input/hid-over-spi.yaml b/Documentation/devicetree/bindings/input/hid-over-spi.yaml new file mode 100644 index 000000000000..b623629ed9d3 --- /dev/null +++ b/Documentation/devicetree/bindings/input/hid-over-spi.yaml @@ -0,0 +1,153 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/input/hid-over-spi.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: HID over SPI Devices + +maintainers: + - Benjamin Tissoires <[email protected]> + - Jiri Kosina <[email protected]> + +description: |+ + HID over SPI provides support for various Human Interface Devices over the + SPI bus. These devices can be for example touchpads, keyboards, touch screens + or sensors. + + The specification has been written by Microsoft and is currently available here: + https://www.microsoft.com/en-us/download/details.aspx?id=103325 + + If this binding is used, the kernel module spi-hid will handle the communication + with the device and the generic hid core layer will handle the protocol. + +allOf: + - $ref: /schemas/input/touchscreen/touchscreen.yaml# + +properties: + compatible: + oneOf: + - items: + - enum: + - microsoft,g6-touch-digitizer + - const: hid-over-spi + - description: Just "hid-over-spi" alone is allowed, but not recommended. + const: hid-over-spi + + reg: + maxItems: 1 + + interrupts: + maxItems: 1 + + reset-gpios: + maxItems: 1 + description: + GPIO specifier for the digitizer's reset pin (active low). The line must + be flagged with GPIO_ACTIVE_LOW. + + vdd-supply: + description: + Regulator for the VDD supply voltage. + + input-report-header-address: + $ref: /schemas/types.yaml#/definitions/uint32 + minimum: 0 + maximum: 0xffffff + description: + A value to be included in the Read Approval packet, listing an address of + the input report header to be put on the SPI bus. This address has 24 + bits. + + input-report-body-address: + $ref: /schemas/types.yaml#/definitions/uint32 + minimum: 0 + maximum: 0xffffff + description: + A value to be included in the Read Approval packet, listing an address of + the input report body to be put on the SPI bus. This address has 24 bits. + + output-report-address: + $ref: /schemas/types.yaml#/definitions/uint32 + minimum: 0 + maximum: 0xffffff + description: + A value to be included in the Output Report sent by the host, listing an + address where the output report on the SPI bus is to be written to. This + address has 24 bits. + + post-power-on-delay-ms: + description: + Optional time in ms required by the device after enabling its regulators + or powering it on, before it is ready for communication. + + minimal-reset-delay-ms: + description: + Optional minimum amount of time in ms that device needs to be in reset + state for the reset to take effect. + + read-opcode: + $ref: /schemas/types.yaml#/definitions/uint8 + description: + Value to be used in Read Approval packets. 1 byte. + + write-opcode: + $ref: /schemas/types.yaml#/definitions/uint8 + description: + Value to be used in Write Approval packets. 1 byte. + + hid-over-spi-flags: + $ref: /schemas/types.yaml#/definitions/uint16 + description: + 16 bits. + Bits 0-12 - Reserved (must be 0) + Bit 13 - SPI Write Mode. Possible values - + * 0b0- Writes are carried out in Single-SPI mode + * 0b1- Writes are carried out in the Multi-SPI mode specified by bits + 14-15 + Bits 14-15 - Multi-SPI Mode. Possible values - + * 0b00- Single SPI + * 0b01- Dual SPI + * 0b10- Quad SPI + +required: + - compatible + - interrupts + - reset-gpios + - vdd-supply + - input-report-header-address + - input-report-body-address + - output-report-address + - read-opcode + - write-opcode + - hid-over-spi-flags + +additionalProperties: false + +examples: + - | + #include <dt-bindings/interrupt-controller/irq.h> + #include <dt-bindings/gpio/gpio.h> + + spi { + #address-cells = <1>; + #size-cells = <0>; + + hid@0 { + compatible = "hid-over-spi"; + reg = <0x0>; + interrupts-extended = <&gpio 42 IRQ_TYPE_EDGE_FALLING>; + reset-gpios = <&gpio 27 GPIO_ACTIVE_LOW>; + vdd-supply = <&pm8350c_l3>; + pinctrl-names = "default"; + pinctrl-0 = <&ts_d6_reset_assert &ts_d6_int_bias>; + input-report-header-address = <0x1000>; + input-report-body-address = <0x1004>; + output-report-address = <0x2000>; + read-opcode = <0x0b>; + write-opcode = <0x02>; + hid-over-spi-flags = <0x0000>; + post-power-on-delay-ms = <5>; + minimal-reset-delay-ms = <5>; + }; + }; \ No newline at end of file -- 2.53.0.473.g4a7958ca14-goog
