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Date:   Wed, 18 Nov 2020 11:55:00 +0000
From:   Mark Brown <broonie@kernel.org>
To:     Viorel Suman <viorel.suman@nxp.com>
Cc:     "Viorel Suman (OSS)" <viorel.suman@oss.nxp.com>,
        Liam Girdwood <lgirdwood@gmail.com>,
        Jaroslav Kysela <perex@perex.cz>,
        Takashi Iwai <tiwai@suse.com>,
        Philipp Zabel <p.zabel@pengutronix.de>,
        Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>,
        "S.j. Wang" <shengjiu.wang@nxp.com>,
        Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>,
        Peter Ujfalusi <peter.ujfalusi@ti.com>,
        Lee Jones <lee.jones@linaro.org>,
        "alsa-devel@alsa-project.org" <alsa-devel@alsa-project.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [RFC PATCH] ASoC: ak4458: use reset control instead of reset gpio
Message-ID: <20201118115500.GB4827@sirena.org.uk>
References: <20201116222036.343635-1-viorel.suman@oss.nxp.com>
 <20201117173901.GH5142@sirena.org.uk>
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On Tue, Nov 17, 2020 at 06:17:36PM +0000, Viorel Suman wrote:
> > On Tue, Nov 17, 2020 at 12:20:36AM +0200, Viorel Suman (OSS) wrote:

> > One thing I'm not clear on is if there's some way to ensure that we don=
't have
> > different instances of the device resetting each other without them not=
icing?
> > Shouldn't be an issue in practice for the use here.

> The way to ensure that we don't have different instances of the device re=
setting each
> other is to rely on the way the "shared" reset is handled by reset API:=
=20
> =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
> +	ak4458->reset =3D devm_reset_control_get_optional_shared(ak4458->dev, N=
ULL);
> +	if (IS_ERR(ak4458->reset))
> +		return PTR_ERR(ak4458->reset);
> =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D

Flip side of that then, how do we know when a reset has actually
happened?

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