Message-ID: <8a19a7b3-f047-3fc5-5002-ce07c1dbdf4a@collabora.com>
Date:   Fri, 17 Feb 2023 11:57:47 +0100
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Subject: Re: [PATCH v2 29/47] clk: mediatek: Propagate struct device with
 mtk_clk_register_dividers()
To:     Chen-Yu Tsai <wenst@chromium.org>
Cc:     mturquette@baylibre.com, sboyd@kernel.org, matthias.bgg@gmail.com,
        johnson.wang@mediatek.com, miles.chen@mediatek.com,
        chun-jie.chen@mediatek.com, daniel@makrotopia.org,
        fparent@baylibre.com, msp@baylibre.com, nfraprado@collabora.com,
        rex-bc.chen@mediatek.com, zhaojh329@gmail.com,
        sam.shih@mediatek.com, edward-jw.yang@mediatek.com,
        yangyingliang@huawei.com, granquet@baylibre.com,
        pablo.sun@mediatek.com, sean.wang@mediatek.com,
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        linux-clk@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-mediatek@lists.infradead.org, kernel@collabora.com
References: <20230214134127.59273-1-angelogioacchino.delregno@collabora.com>
 <20230214134127.59273-30-angelogioacchino.delregno@collabora.com>
 <CAGXv+5EEO2RMzwkknMEwYZmtO7PbDhOTj_=yRrU0UHeCdc==iw@mail.gmail.com>
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From:   AngeloGioacchino Del Regno 
        <angelogioacchino.delregno@collabora.com>
In-Reply-To: <CAGXv+5EEO2RMzwkknMEwYZmtO7PbDhOTj_=yRrU0UHeCdc==iw@mail.gmail.com>
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Il 17/02/23 05:09, Chen-Yu Tsai ha scritto:
> On Tue, Feb 14, 2023 at 9:42 PM AngeloGioacchino Del Regno
> <angelogioacchino.delregno@collabora.com> wrote:
>>
>> Propagate struct device for divider clocks registered through clk-mtk
>> helpers to be able to get runtime PM support for MTK clocks.
> 
> Sidenote: I think we still need to call pm_runtime_enable() (or some other
> function) on the underlying device before any clk_hw_register() calls are
> made for the clk core to pick up runtime PM support?
> 

The clk_core checks...

	if (dev && pm_runtime_enabled(dev))
		core->rpm_enabled = true;

...at __clk_register() time, and there's no way to enable it *later*, which
is something that may or may not be good for us.

We could call pm_runtime_enable() on the clock driver itself (so, in simple_probe)
but that's something I didn't want to do right now because this needs a rather big
amount of testing on multiple SoCs.

But yes I agree with you on that we still need to *flip the switch* to actually
enable rpm support. These commits are meant to make us able to do that in one line,
instead of one line per file :-P

>> Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
> 
> Reviewed-by: Chen-Yu Tsai <wenst@chromium.org>

Thanks! :-)