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Date:   Thu, 17 Nov 2022 19:05:32 +0000
To:     linux-input@vger.kernel.org
From:   "Lin, Meng-Bo" <linmengbo0689@protonmail.com>
Cc:     Dmitry Torokhov <dmitry.torokhov@gmail.com>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Linus Walleij <linus.walleij@linaro.org>,
        Alistair Francis <alistair@alistair23.me>,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH 1/2] dt-bindings: input: cyttsp5: document vddio-supply
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The Samsung touchscreen controllers are often used with external pull-up
for the interrupt line and the I2C lines, so we might need to enable
a regulator to bring the lines into usable state. Otherwise, this might
cause spurious interrupts and reading from I2C will fail.

Document support for a "vddio-supply" that is enabled by the cyttsp5
driver so that the regulator gets enabled when needed.

Signed-off-by: Lin, Meng-Bo <linmengbo0689@protonmail.com>
---
 .../devicetree/bindings/input/touchscreen/cypress,tt21000.yaml | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/Documentation/devicetree/bindings/input/touchscreen/cypress,tt=
21000.yaml b/Documentation/devicetree/bindings/input/touchscreen/cypress,tt=
21000.yaml
index 1959ec394768..869a9bdd962f 100644
--- a/Documentation/devicetree/bindings/input/touchscreen/cypress,tt21000.y=
aml
+++ b/Documentation/devicetree/bindings/input/touchscreen/cypress,tt21000.y=
aml
@@ -34,6 +34,9 @@ properties:
   vdd-supply:
     description: Regulator for voltage.
=20
+  vddio-supply:
+    description: Optional Regulator for I/O voltage.
+
   reset-gpios:
     maxItems: 1
=20
--=20
2.30.2