dt-bindings: pinctrl: qcom: Add output-enable
In the patch ("dt-bindings: pinctrl: qcom: tlmm should use output-disable, not input-enable") we allowed setting "output-disable" for TLMM pinctrl states. Let's also add "output-enable". At first blush this seems a needless thing to do. Specifically: - In Linux (and presumably any other OSes using the same device trees) the GPIO/pinctrl driver knows to automatically enable the output when a GPIO is changed to an output. Thus in most cases specifying "output-enable" is superfluous and should be avoided. - If we need to set a pin's default state we already have "output-high" and "output-low" and these properties already imply "output-enabled" (at least on the Linux Qualcomm TLMM driver). However, there is one instance where "output-enable" seems like it could be useful: sleep states. It's not uncommon to want to configure pins as inputs (with appropriate pulls) when the driver controlling them is in a low power state. Then we want the pins back to outputs when the driver wants things running normally. To accomplish this we'd want to be able to use "output-enable". Then the "default" state could have "output-enable" and the "sleep" state could have "output-disable". NOTE: in all instances I'm aware of, we'd only want to use "output-enable" on pins that are configured as "gpio". The Qualcomm documentation that I have access to says that "output-enable" only does something useful when in GPIO mode. Signed-off-by: Douglas Anderson <dianders@chromium.org> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> Acked-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20230323102605.7.I7874c00092115c45377c2a06f7f133356956686e@changeidSigned-off-by: Linus Walleij <linus.walleij@linaro.org>
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