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From:   Douglas Anderson <dianders@chromium.org>
To:     Bjorn Andersson <andersson@kernel.org>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Mark Brown <broonie@kernel.org>,
        Linus Walleij <linus.walleij@linaro.org>
Cc:     Matthias Kaehlcke <mka@chromium.org>,
        Konrad Dybcio <konrad.dybcio@linaro.org>,
        linux-gpio@vger.kernel.org, Stephen Boyd <swboyd@chromium.org>,
        devicetree@vger.kernel.org, linux-arm-msm@vger.kernel.org,
        linux-spi@vger.kernel.org,
        Douglas Anderson <dianders@chromium.org>,
        Andy Gross <agross@kernel.org>, linux-kernel@vger.kernel.org
Subject: [PATCH 06/14] dt-bindings: pinctrl: qcom: tlmm should use output-disable, not input-enable
Date:   Thu, 23 Mar 2023 10:30:10 -0700
Message-Id: <20230323102605.6.I291ce0ba2c6ea80b341659c4f75a567a76dd7ca6@changeid>
In-Reply-To: <20230323173019.3706069-1-dianders@chromium.org>
References: <20230323173019.3706069-1-dianders@chromium.org>
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As evidenced by the Qualcomm TLMM Linux driver, the TLMM IP block in
Qualcomm SoCs has a bit to enable/disable the output for a pin that's
configured as a GPIO but _not_ a bit to enable/disable an input
buffer. Current device trees that are specifying "input-enable" for
pins managed by TLMM are either doing so needlessly or are using it to
mean "output-disable".

Presumably the current convention of using "input-enable" to mean
"output-disable" stems from the fact that "output-disable" is a "new"
property from 2017. It was introduced in commit 425562429d4f
("pinctrl: generic: Add output-enable property"). The "input-enable"
handling in Qualcomm drivers is from 2015 introduced in commit
407f5e392f9c ("pinctrl: qcom: handle input-enable pinconf property").

Given that there's no other use for "input-enable" for TLMM, we can
still handle old device trees in code, but let's encourage people to
move to the proper / documented property by updating the bindings.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
---

 .../devicetree/bindings/pinctrl/qcom,tlmm-common.yaml          | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/pinctrl/qcom,tlmm-common.yaml b/Documentation/devicetree/bindings/pinctrl/qcom,tlmm-common.yaml
index cb5ba1bd6f8d..5a815c199642 100644
--- a/Documentation/devicetree/bindings/pinctrl/qcom,tlmm-common.yaml
+++ b/Documentation/devicetree/bindings/pinctrl/qcom,tlmm-common.yaml
@@ -75,7 +75,8 @@ $defs:
       bias-pull-down: true
       bias-pull-up: true
       bias-disable: true
-      input-enable: true
+      input-enable: false
+      output-disable: true
       output-high: true
       output-low: true
 
-- 
2.40.0.348.gf938b09366-goog