[PATCH v4 1/2] dt-bindings: input: i2c-hid: Introduce FocalTech FT8112

[PATCH v4 1/2] dt-bindings: input: i2c-hid: Introduce FocalTech FT8112

[daniel_peng]

From: Daniel Peng <Daniel_Peng@pegatron.corp-partner.google.com>

The FocalTech FT8112 touch screen chip same as Ilitek ili2901 controller
has a reset gpio. The difference is that they have different
post_gpio_reset_on_delay_ms.
FocalTech FT8112 also uses 3.3V power supply.

Signed-off-by: Daniel Peng <Daniel_Peng@pegatron.corp-partner.google.com>
---

Changes in v4:
- Move change log of v3 under "---" correctly as below 4 items.

- Modified the subject description.
- Modified maintainers to myself of this binding file.
- Fixed the extra '>' on section of "interrupts = <15 IRQ_TYPE_LEVEL_LOW>;" and confirm command 'make dt_binding_check' correctly.
- Restored MAINTAINERS file.

 .../bindings/input/focaltech,ft8112.yaml      | 66 +++++++++++++++++++
 1 file changed, 66 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/input/focaltech,ft8112.yaml

diff --git a/Documentation/devicetree/bindings/input/focaltech,ft8112.yaml b/Documentation/devicetree/bindings/input/focaltech,ft8112.yaml
new file mode 100644
index 000000000000..197f30b14d45
--- /dev/null
+++ b/Documentation/devicetree/bindings/input/focaltech,ft8112.yaml
@@ -0,0 +1,66 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/input/focaltech,ft8112.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: FocalTech FT8112 touchscreen controller
+
+maintainers:
+  - Daniel Peng <Daniel_Peng@pegatron.corp-partner.google.com>
+
+description:
+  Supports the FocalTech FT8112 touchscreen controller.
+  This touchscreen controller uses the i2c-hid protocol with a reset GPIO.
+
+allOf:
+  - $ref: /schemas/input/touchscreen/touchscreen.yaml#
+
+properties:
+  compatible:
+    enum:
+      - focaltech,ft8112
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  panel: true
+
+  reset-gpios:
+    maxItems: 1
+
+  vcc33-supply: true
+
+  vccio-supply: true
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - vcc33-supply
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+    #include <dt-bindings/interrupt-controller/irq.h>
+
+    i2c {
+      #address-cells = <1>;
+      #size-cells = <0>;
+
+      touchscreen@38 {
+        compatible = "focaltech,ft8112";
+        reg = <0x38>;
+
+        interrupt-parent = <&pio>;
+        interrupts = <15 IRQ_TYPE_LEVEL_LOW>;
+
+        reset-gpios = <&pio 126 GPIO_ACTIVE_LOW>;
+        vcc33-supply = <&pp3300_tchscr_x>;
+      };
+    };
-- 
2.34.1

Re: [PATCH v4 1/2] dt-bindings: input: i2c-hid: Introduce FocalTech FT8112

[Krzysztof Kozlowski]

On Thu, Nov 13, 2025 at 02:00:55PM +0800, daniel_peng@pegatron.corp-partner.google.com wrote:
> From: Daniel Peng <Daniel_Peng@pegatron.corp-partner.google.com>
> 
> The FocalTech FT8112 touch screen chip same as Ilitek ili2901 controller

So keep the device in that binding under enum. No need to create
document for every device, even if they were different but here it is
pretty obvious - same chip.

Best regards,
Krzysztof

Re: [PATCH v4 1/2] dt-bindings: input: i2c-hid: Introduce FocalTech FT8112

[Krzysztof Kozlowski]

On 13/11/2025 11:44, Daniel Peng wrote:
> Hi Krzysztof,
> 
> Sorry for the confusion.
> I just refer ilitek,ili2901.yaml as example to modify correct information
> for this device. And I create document file for FocalTech FT8112 device for
> Skywalker platform only.
> Moreover, modified related interrupt and reset gpio to map for Skywaler
> platform(MT8189).
> 
> I think it would be good to create document. If any, please let me know.
> 


Please don't top post.

There is no need for new document, everything is identical, so just add
new compatible to the other binding.

Best regards,
Krzysztof

Re: [PATCH v4 1/2] dt-bindings: input: i2c-hid: Introduce FocalTech FT8112

[Krzysztof Kozlowski]

On 14/11/2025 07:13, Daniel Peng wrote:
>> On 13/11/2025 11:44, Daniel Peng wrote:
>>> From: Daniel Peng <Daniel_Peng@pegatron.corp-partner.google.com>
>>>
>>> The FocalTech FT8112 touch screen chip same as Ilitek ili2901 controller
>>
>> So keep the device in that binding under enum. No need to create
>> document for every device, even if they were different but here it is
>> pretty obvious - same chip.
>>
>> Best regards,
>> Krzysztof
> 
> Sorry for the confusion. Might be I use the wrong description, and make you
> feel that is the same chip and no need to create new binding file.
> 
> Here are my question:
> 1. I had referred to ilitek,ili2901.yaml and copied as new file for
> focaltech,ft8112.yaml. Moreover, I also modified to replace related
> information for Focaltech FT8112 touchscreen.
> There are many different descriptions in the file, such as "compatible",
> "reg", "interrupt-parent", "interrupts", "reset-gpios", ... .etc.
> If "No need to create document for every device" now, could you help to
> provide what file that I need to keep the device in the binding under enum?

You wrote it is the same chip as ili2901, so obviously in ili2901.

Best regards,
Krzysztof