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Date:   Fri, 7 Jul 2023 16:05:57 +0200
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Subject: Re: [PATCH v3 5/6] thermal/drivers/mediatek/lvts_thermal: Don't leave
 threshold zeroed
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        <nfraprado@collabora.com>,
        Daniel Lezcano <daniel.lezcano@linaro.org>
Cc:     Alexandre Bailon <abailon@baylibre.com>,
        Balsam CHIHI <bchihi@baylibre.com>,
        AngeloGioacchino Del Regno 
        <angelogioacchino.delregno@collabora.com>,
        Chen-Yu Tsai <wenst@chromium.org>, kernel@collabora.com,
        Amit Kucheria <amitk@kernel.org>,
        Matthias Brugger <matthias.bgg@gmail.com>,
        "Rafael J. Wysocki" <rafael@kernel.org>,
        Zhang Rui <rui.zhang@intel.com>,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        linux-mediatek@lists.infradead.org, linux-pm@vger.kernel.org
References: <20230706153823.201943-1-nfraprado@collabora.com>
 <20230706153823.201943-6-nfraprado@collabora.com>
From:   Alexandre Mergnat <amergnat@baylibre.com>
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On 06/07/2023 17:37, Nícolas F. R. A. Prado wrote:
> The thermal framework might leave the low threshold unset if there
> aren't any lower trip points. This leaves the register zeroed, which
> translates to a very high temperature for the low threshold. The
> interrupt for this threshold is then immediately triggered, and the
> state machine gets stuck, preventing any other temperature monitoring
> interrupts to ever trigger.
> 
> (The same happens by not setting the Cold or Hot to Normal thresholds
> when using those)
> 
> Set the unused threshold to a valid low value. This value was chosen so
> that for any valid golden temperature read from the efuse, when the
> value is converted to raw and back again to milliCelsius, the result
> doesn't underflow.

Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>

-- 
Regards,
Alexandre