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Date:   Thu, 22 Sep 2022 16:04:38 +0200
From:   Borislav Petkov <bp@suse.de>
To:     Hans de Goede <hdegoede@redhat.com>
Cc:     Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        "Limonciello, Mario" <mario.limonciello@amd.com>,
        Jan =?utf-8?B?RMSFYnJvxZs=?= <jsd@semihalf.com>,
        linux-kernel@vger.kernel.org, linux-i2c@vger.kernel.org,
        jarkko.nikula@linux.intel.com, wsa@kernel.org,
        rrangel@chromium.org, upstream@semihalf.com,
        Muralidhara M K <muralimk@amd.com>,
        Naveen Krishna Chatradhi <nchatrad@amd.com>
Subject: Re: [PATCH -next 1/2] i2c: designware: Switch from using MMIO access
 to SMN access
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On Thu, Sep 22, 2022 at 03:48:07PM +0200, Hans de Goede wrote:
> Right, thank you for Cc-ing me. At least on X86 there are several platforms
> (and 100-s of device models) which use a PMIC connected to the i2c-designware
> controller and this PMIC gets poked directly from ACPI _S0 and _S3
> (power on/off) methods. So the I2C bus driver needs to *bind* to the controller
> as soon as we find its description in ACPI, otherwise we get a whole bunch
> of failed ACPI OpRegion access errors as well as various actual really issues.

Thanks for explaining - I couldn't find the reason why it has to be a
subsys_initcall.

> So please keep this as a subsys initcall.

Which means, init_amd_nbs() would have to be sorted to run before
dw_i2c_init_driver()...

-- 
Regards/Gruss,
    Boris.

SUSE Software Solutions Germany GmbH
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