linux-kernel - Re: [PATCH 03/15] clk: qcom: gcc-sm6375: Unregister critical clocks

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Message-ID: <ZLaRtrH85v4kpSvb@hovoldconsulting.com>
Date:   Tue, 18 Jul 2023 15:20:54 +0200
From:   Johan Hovold <johan@...nel.org>
To:     Konrad Dybcio <konrad.dybcio@...aro.org>
Cc:     Bjorn Andersson <andersson@...nel.org>,
        Andy Gross <agross@...nel.org>,
        Michael Turquette <mturquette@...libre.com>,
        Stephen Boyd <sboyd@...nel.org>,
        Rob Herring <robh+dt@...nel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@...aro.org>,
        Conor Dooley <conor+dt@...nel.org>,
        Marijn Suijten <marijn.suijten@...ainline.org>,
        linux-arm-msm@...r.kernel.org, linux-clk@...r.kernel.org,
        linux-kernel@...r.kernel.org, devicetree@...r.kernel.org
Subject: Re: [PATCH 03/15] clk: qcom: gcc-sm6375: Unregister critical clocks

On Mon, Jul 17, 2023 at 05:19:10PM +0200, Konrad Dybcio wrote:
> Some clocks need to be always-on, but we don't really do anything
> with them, other than calling enable() once and telling Linux they're
> enabled.
> 
> Unregister them to save a couple of bytes and, perhaps more
> importantly, allow for runtime suspend of the clock controller device,
> as CLK_IS_CRITICAL prevents the latter.

But this doesn't sound right. How can you disable a controller which
still has clocks enabled?

Shouldn't instead these clocks be modelled properly so that they are
only enabled when actually needed?

Johan