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Message-ID: <24952eda-9821-4634-aaa4-e636119f99fd@collabora.com>
Date:   Fri, 21 Jul 2023 10:53:46 +0200
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Subject: Re: [PATCH RESEND v2 4/7] regulator: mt6358: Fail probe on unknown
 chip ID
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To:     Chen-Yu Tsai <wenst@chromium.org>, Lee Jones <lee@kernel.org>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Conor Dooley <conor+dt@kernel.org>,
        Mark Brown <broonie@kernel.org>,
        Liam Girdwood <lgirdwood@gmail.com>,
        Matthias Brugger <matthias.bgg@gmail.com>
Cc:     devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org
References: <20230721082903.2038975-1-wenst@chromium.org>
 <20230721082903.2038975-5-wenst@chromium.org>
From:   AngeloGioacchino Del Regno 
        <angelogioacchino.delregno@collabora.com>
In-Reply-To: <20230721082903.2038975-5-wenst@chromium.org>
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Il 21/07/23 10:28, Chen-Yu Tsai ha scritto:
> The MT6358 and MT6366 PMICs, and likely many others from MediaTek, have
> a chip ID register, making the chip semi-discoverable.
> 
> The driver currently supports two PMICs and expects to be probed on one
> or the other. It does not account for incorrect mfd driver entries or
> device trees. While these should not happen, if they do, it could be
> catastrophic for the device. The driver should be sure the hardware is
> what it expects.
> 
> Make the driver fail to probe if the chip ID presented is not a known
> one.
> 
> Suggested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
> Fixes: f0e3c6261af1 ("regulator: mt6366: Add support for MT6366 regulator")
> Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>

Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>