Re: [PATCH -next 1/2] i2c: designware: Switch from using MMIO access to SMN access

From: Borislav Petkov
Date: Thu Sep 22 2022 - 10:04:50 EST


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.

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