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Date:   Tue, 28 Mar 2023 07:44:26 -0700
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Subject: Re: [PATCH v6 5/5] mfd: max77541: Add ADI MAX77541/MAX77540 PMIC
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To:     Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        =?UTF-8?Q?Nuno_S=c3=a1?= <noname.nuno@gmail.com>
Cc:     Mark Brown <broonie@kernel.org>,
        "Sahin, Okan" <Okan.Sahin@analog.com>, Lee Jones <lee@kernel.org>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
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        Cosmin Tanislav <demonsingur@gmail.com>,
        Stephen Boyd <sboyd@kernel.org>,
        Caleb Connolly <caleb.connolly@linaro.org>,
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        "Bolboaca, Ramona" <Ramona.Bolboaca@analog.com>,
        ChiYuan Huang <cy_huang@richtek.com>,
        "Tilki, Ibrahim" <Ibrahim.Tilki@analog.com>,
        William Breathitt Gray <william.gray@linaro.org>,
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        Haibo Chen <haibo.chen@nxp.com>,
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        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
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From:   Lars-Peter Clausen <lars@metafoo.de>
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On 3/28/23 07:35, Andy Shevchenko wrote:
> On Tue, Mar 28, 2023 at 04:18:30PM +0200, Nuno Sá wrote:
>> On Tue, 2023-03-28 at 14:46 +0100, Mark Brown wrote:
>>> On Tue, Mar 28, 2023 at 03:26:44PM +0200, Nuno Sá wrote:
>>>
>>>> IIRC, regmap_read() is not really reentrant and it is used in the
>>>> IIO
>>>> driver on the sysfs interface. So, yeah, I think you need the
>>>> regmap
>>>> lock and better just leave the config as is. Yes, the lock is opt-
>>>> out
>>>> so let's not disable it :)
>>> All the regmap operations are fully thread safe.
>> Even if 'config->disable_locking' is set? I think that is what's being
>> discussed in here...
> In case the driver has its own lock to serialize IO how on earth the regmap
> lock is needed.
But the driver does not have its own lock.