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To:     Matthias Brugger <matthias.bgg@gmail.com>,
        Weiyi Lu <weiyi.lu@mediatek.com>
From:   Stephen Boyd <sboyd@kernel.org>
Subject: Re: [RFC v1] clk: core: support clocks that need to be enabled during re-parent
Cc:     James Liao <jamesjj.liao@mediatek.com>,
        Fan Chen <fan.chen@mediatek.com>,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        linux-mediatek@lists.infradead.org, linux-clk@vger.kernel.org,
        srv_heupstream@mediatek.com, stable@vger.kernel.org,
        Weiyi Lu <weiyi.lu@mediatek.com>,
        Biao Huang <biao.huang@mediatek.com>
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Date:   Tue, 25 Jun 2019 15:14:14 -0700
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Quoting Weiyi Lu (2019-06-09 20:44:53)
> When using property assigned-clock-parents to assign parent clocks,
> core clocks might still be disabled during re-parent.
> Add flag 'CLK_OPS_CORE_ENABLE' for those clocks must be enabled
> during re-parent.
>=20
> Signed-off-by: Weiyi Lu <weiyi.lu@mediatek.com>

Can you further describe the scenario where this is a problem? Is it
some sort of clk that is enabled by default out of the bootloader and is
then configured to have an 'assigned-clock-parents' property to change
the parent, but that clk needs to be "enabled" so that the framework
turns on the parents for the parent switch?