linux-kernel - Re: [PATCH 1/6] ASoC: wcd938x: switch to using gpiod API

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Message-ID: <6b355201-a957-4fca-a513-d5fa0742fb40@sirena.org.uk>
Date:   Thu, 20 Apr 2023 12:58:08 +0100
From:   Mark Brown <broonie@...nel.org>
To:     Krzysztof Kozlowski <krzysztof.kozlowski@...aro.org>
Cc:     Vinod Koul <vkoul@...nel.org>,
        Bard Liao <yung-chuan.liao@...ux.intel.com>,
        Pierre-Louis Bossart <pierre-louis.bossart@...ux.intel.com>,
        Sanyog Kale <sanyog.r.kale@...el.com>,
        Andy Gross <agross@...nel.org>,
        Bjorn Andersson <andersson@...nel.org>,
        Konrad Dybcio <konrad.dybcio@...aro.org>,
        Liam Girdwood <lgirdwood@...il.com>,
        Jaroslav Kysela <perex@...ex.cz>,
        Takashi Iwai <tiwai@...e.com>, alsa-devel@...a-project.org,
        linux-kernel@...r.kernel.org, linux-arm-msm@...r.kernel.org,
        Dmitry Torokhov <dmitry.torokhov@...il.com>,
        Patrick Lai <quic_plai@...cinc.com>
Subject: Re: [PATCH 1/6] ASoC: wcd938x: switch to using gpiod API

On Thu, Apr 20, 2023 at 12:16:12PM +0200, Krzysztof Kozlowski wrote:

> -	gpio_direction_output(wcd938x->reset_gpio, 0);
> -	/* 20us sleep required after pulling the reset gpio to LOW */
> +	gpiod_set_value_cansleep(wcd938x->reset_gpio, 1);
> +	/* 20us sleep required after asserting the reset gpio */

This is inverting the sense of the GPIO in the API from active low to
active high which will mean we're introducing a new reliance on having
the signal described as active low in DT.  That's an ABI concern.

I remain deeply unconvinced that remapping active low outputs like this
in the GPIO API is helping.

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