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Date:   Wed, 21 Jul 2021 15:10:29 +0200
From:   Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
To:     Arnd Bergmann <arnd@arndb.de>
Cc:     Bjorn Helgaas <bhelgaas@google.com>,
        Linuxarm <linuxarm@huawei.com>,
        Mauro Carvalho Chehab <mauro.chehab@huawei.com>,
        Krzysztof =?UTF-8?B?V2ls?= =?UTF-8?B?Y3p5xYRza2k=?= 
        <kw@linux.com>, Alex Dewar <alex.dewar90@gmail.com>,
        Henry Styles <hes@sifive.com>,
        Jaehoon Chung <jh80.chung@samsung.com>,
        Kevin Hilman <khilman@baylibre.com>,
        Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>,
        Manivannan Sadhasivam <mani@kernel.org>,
        Paul Walmsley <paul.walmsley@sifive.com>,
        Rob Herring <robh@kernel.org>,
        Wesley Sheng <wesley.sheng@amd.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        linux-pci <linux-pci@vger.kernel.org>
Subject: Re: [PATCH v7 11/10] PCI: kirin: Allow building it as a module
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Em Wed, 21 Jul 2021 13:55:07 +0200
Arnd Bergmann <arnd@arndb.de> escreveu:

> On Wed, Jul 21, 2021 at 12:15 PM Mauro Carvalho Chehab
> <mchehab+huawei@kernel.org> wrote:
> >
> > There's nothing preventing this driver to be loaded as a
> > module. So, change its config from bool to tristate.
> >
> > Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>  
> 
> No objections from me, but I wonder if you would also consider making the
> module removable. It's currently marked as 'builtin_platform_driver',
> so you can load but not remove it. Rob has done some bug fixes that make
> it possible to remove similar drivers, so it's probably not much work
> here either.

Yeah, I can probably work on a patch to unbind/remove this driver.

Never actually tried to write a patch removing the PCIe BUS, so no
idea if the refcounts for the in-board Ethernet NIC, M.2 and mini-PCIe
slots will be properly handled. If refcount is handled properly, I
guess a patch like that won't be hard, at least for Kirin 970 PHY.

The Kirin 960 PHY will require a small change at the current version,
as it currently misses the power_off logic.

I also need to double-check if devm resources will be freed at the 
driver removal time, as, with some past tests with media devices,
we had some issues with that.

Thanks,
Mauro