From f9d803784f8dfea60f394d7fc94084c5f1eb4027 Mon Sep 17 00:00:00 2001
From: Stephan Gerhold <stephan@gerhold.net>
Date: Wed, 17 Sep 2025 14:11:18 -0700
Subject: [PATCH] dt-bindings: input: touchscreen: document Himax HX852x(ES)

Himax HX852x(ES) is a touch panel controller with optional support
for capacitive touch keys.

Unfortunately, the model naming is quite unclear and confusing. There
seems to be a distinction between models (e.g. HX8526) and the "series"
suffix (e.g. -A, -B, -C, -D, -E, -ES). But this doesn't seem to be
applied very consistently because e.g. HX8527-E(44) actually seems to
belong to the -ES series.

The compatible consists of the actual part number followed by the
"series" as fallback compatible. Typically only the latter will be
interesting for drivers as there is no relevant difference on the
driver side.

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
Link: https://lore.kernel.org/r/20250915-hx852x-v5-1-b938182f1056@linaro.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---
 .../input/touchscreen/himax,hx852es.yaml      | 81 +++++++++++++++++++
 1 file changed, 81 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/input/touchscreen/himax,hx852es.yaml

diff --git a/Documentation/devicetree/bindings/input/touchscreen/himax,hx852es.yaml b/Documentation/devicetree/bindings/input/touchscreen/himax,hx852es.yaml
new file mode 100644
index 000000000000..40a60880111d
--- /dev/null
+++ b/Documentation/devicetree/bindings/input/touchscreen/himax,hx852es.yaml
@@ -0,0 +1,81 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/input/touchscreen/himax,hx852es.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Himax HX852x(ES) touch panel controller
+
+maintainers:
+  - Stephan Gerhold <stephan@gerhold.net>
+
+allOf:
+  - $ref: touchscreen.yaml#
+
+properties:
+  compatible:
+    items:
+      - enum:
+          - himax,hx8525e
+          - himax,hx8526e
+          - himax,hx8527e
+      - const: himax,hx852es
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+    description: Touch Screen Interrupt (TSIX), active low
+
+  reset-gpios:
+    maxItems: 1
+    description: External Reset (XRES), active low
+
+  vcca-supply:
+    description: Analog power supply (VCCA)
+
+  vccd-supply:
+    description: Digital power supply (VCCD)
+
+  touchscreen-inverted-x: true
+  touchscreen-inverted-y: true
+  touchscreen-size-x: true
+  touchscreen-size-y: true
+  touchscreen-swapped-x-y: true
+
+  linux,keycodes:
+    minItems: 1
+    maxItems: 4
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - reset-gpios
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+    #include <dt-bindings/input/input.h>
+    #include <dt-bindings/interrupt-controller/irq.h>
+
+    i2c {
+      #address-cells = <1>;
+      #size-cells = <0>;
+
+      touchscreen@48 {
+        compatible = "himax,hx8527e", "himax,hx852es";
+        reg = <0x48>;
+        interrupt-parent = <&tlmm>;
+        interrupts = <13 IRQ_TYPE_LEVEL_LOW>;
+        reset-gpios = <&tlmm 12 GPIO_ACTIVE_LOW>;
+        vcca-supply = <&reg_ts_vcca>;
+        vccd-supply = <&pm8916_l6>;
+        linux,keycodes = <KEY_BACK KEY_HOMEPAGE KEY_APPSELECT>;
+      };
+    };
+
+...
-- 
2.51.0