Date:   Wed, 24 Nov 2021 15:40:00 +0000
From:   Lee Jones <lee.jones@linaro.org>
To:     Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Cc:     linuxarm@huawei.com, mauro.chehab@huawei.com,
        linux-kernel@vger.kernel.org, Hans de Goede <hdegoede@redhat.com>
Subject: Re: [PATCH] mfd: Kconfig: change INTEL_SOC_PMIC_CHTDC_TI to bool
Message-ID: <YZ5c0LO5Ocaq+B7c@google.com>
References: <f12ed3dea697e6fdcfcaf9b6cc862ffa7aac005b.1635490923.git.mchehab+huawei@kernel.org>
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On Fri, 29 Oct 2021, Mauro Carvalho Chehab wrote:

> The INTEL_SOC_PMIC_CHTDC_TI should be initialized early, before
> loading the fbcon driver, as otherwise the i915 driver will
> fail to configure pwm:
> 
> [   13.674287] fb0: switching to inteldrmfb from EFI VGA
> [   13.682380] Console: switching to colour dummy device 80x25
> [   13.682468] i915 0000:00:02.0: vgaarb: deactivate vga console
> [   13.682686] [drm] Supports vblank timestamp caching Rev 2 (21.10.2013).
> [   13.685773] i915 0000:00:02.0: vgaarb: changed VGA decodes: olddecodes=io+mem,decodes=io+mem:owns=io+mem
> [   13.686219] i915 0000:00:02.0: [drm] *ERROR* Failed to configure the pwm chip
> [   13.699572] [drm] Initialized i915 1.6.0 20200313 for 0000:00:02.0 on minor 0
> [   13.739044] fbcon: i915drmfb (fb0) is primary device
> [   14.037792] intel_soc_pmic_exec_mipi_pmic_seq_element: No PMIC registered
> ...
> [   24.621403] intel_pmic_install_opregion_handler: Ask to register OpRegion for bus ID=PMI2, HID=INT33F5
> [   24.630540] intel_pmic_install_opregion_handler: OpRegion registered
> 
> (some extra debug printk's were added to the above)
> 
> As suggested by Hans, this patch also addresses an issue with
> the dependencies, as, for this driver to be a bool, it also
> need the I2C core and the I2C_DESIGNWARE driver to be builtin.
> 
> Suggested-by: Hans de Goede <hdegoede@redhat.com>
> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
> ---
>  drivers/mfd/Kconfig | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
> index ca0edab91aeb..f9092c79c4e8 100644
> --- a/drivers/mfd/Kconfig
> +++ b/drivers/mfd/Kconfig
> @@ -632,7 +632,7 @@ config INTEL_SOC_PMIC_CHTWC
>  config INTEL_SOC_PMIC_CHTDC_TI
>  	tristate "Support for Intel Cherry Trail Dollar Cove TI PMIC"
>  	depends on GPIOLIB
> -	depends on I2C
> +	depends on I2C = y && I2C_DESIGNWARE_PLATFORM=y

The lack of formatting consistency here is eating me up inside!

>  	depends on ACPI
>  	depends on X86
>  	select MFD_CORE
> @@ -642,6 +642,10 @@ config INTEL_SOC_PMIC_CHTDC_TI
>  	  Select this option for supporting Dollar Cove (TI version) PMIC
>  	  device that is found on some Intel Cherry Trail systems.
>  
> +	  This option is a bool as it provides an ACPI OpRegion which must be
> +	  available before any devices using it are probed. This option also
> +	  needs the designware-i2c driver to be builtin for the same reason.

Is there no way around this?

We do have early module loading available.

>  config INTEL_SOC_PMIC_MRFLD
>  	tristate "Support for Intel Merrifield Basin Cove PMIC"
>  	depends on GPIOLIB

-- 
Lee Jones [李琼斯]
Senior Technical Lead - Developer Services
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