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Message-ID: <8cce4dae-c653-515b-1a5d-024986afbabf@rasmusvillemoes.dk>
Date:   Mon, 21 Nov 2022 10:44:22 +0100
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Subject: Re: [PATCH] clk: imx8mp: register driver at arch_initcall time
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To:     Fabio Estevam <festevam@gmail.com>
Cc:     Abel Vesa <abelvesa@kernel.org>,
        Michael Turquette <mturquette@baylibre.com>,
        Stephen Boyd <sboyd@kernel.org>,
        Shawn Guo <shawnguo@kernel.org>,
        Sascha Hauer <s.hauer@pengutronix.de>,
        Pengutronix Kernel Team <kernel@pengutronix.de>,
        NXP Linux Team <linux-imx@nxp.com>,
        linux-kernel@vger.kernel.org, linux-clk@vger.kernel.org
References: <20220928124108.500369-1-linux@rasmusvillemoes.dk>
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From:   Rasmus Villemoes <linux@rasmusvillemoes.dk>
In-Reply-To: <CAOMZO5AXSSkHpeuHNRQ6qkFoe2uiFLVxndz1u7_y7s9cLD9ppw@mail.gmail.com>
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On 19/11/2022 23.02, Fabio Estevam wrote:
> On Sat, Nov 19, 2022 at 6:57 PM Rasmus Villemoes
> <linux@rasmusvillemoes.dk> wrote:
> 
>> Sorry, I don't follow. Before this patch, the driver also implicitly had
>> a module_exit() doing exactly this platform_driver_unregister(), it was
>> just hidden inside the module_platform_driver() macro. And I think
>> that's necessary if one wants to test that the module can be loaded and
>> unloaded (I don't think it's ever useful or even possible to have it be
>> a module on an actual imx8mp board).
> 
> You cannot load/unload it due to .suppress_bind_attrs = true, being passed.

That doesn't seem to be true. To test, I just built the imx8mq clk
driver as a module, and I could certainly both load and unload that on
my imx8mp platform. Sure, no "bind" attribute shows up in the
/sys/bus/platform/drivers/imx8mq-ccm/ directory, which is exactly what
one expects, but the module can be loaded just fine. And since it can be
loaded, it should also have a proper __exit call for deregistering the
driver on unload.

Rasmus