Message-ID: <3d4a0cb2-e9b6-68a9-f844-4bea89f8a9b0@linaro.org>
Date:   Thu, 9 Mar 2023 02:48:33 +0200
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Subject: Re: [PATCH RFT v2 03/14] clk: qcom: smd-rpm: Add .is_prepared hook
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To:     Konrad Dybcio <konrad.dybcio@linaro.org>,
        Andy Gross <agross@kernel.org>,
        Bjorn Andersson <andersson@kernel.org>,
        Michael Turquette <mturquette@baylibre.com>,
        Stephen Boyd <sboyd@kernel.org>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>
Cc:     linux-arm-msm@vger.kernel.org, linux-clk@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>,
        devicetree@vger.kernel.org, Shawn Guo <shawn.guo@linaro.org>
References: <20230303-topic-rpmcc_sleep-v2-0-ae80a325fe94@linaro.org>
 <20230303-topic-rpmcc_sleep-v2-3-ae80a325fe94@linaro.org>
From:   Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
In-Reply-To: <20230303-topic-rpmcc_sleep-v2-3-ae80a325fe94@linaro.org>
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Precedence: bulk

On 08/03/2023 23:35, Konrad Dybcio wrote:
> From: Shawn Guo <shawn.guo@linaro.org>
> 
> The RPM clocks are enabled/disabled through clk framework prepare/unprepare
> hooks.  Without .is_prepared hook, those unused RPM clocks will not be
> disabled by core function clk_unprepare_unused_subtree(), because
> clk_core_is_prepared() always returns 0.
> 
> Add .is_prepared hook to clk_ops and return the clock prepare (enable)
> state, so that those unused RPM clocks can be disabled by clk framework.
> 
> Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
> [Konrad: rebase, don't duplicate the enable func]
> Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
> ---
>   drivers/clk/qcom/clk-smd-rpm.c | 2 ++
>   1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/clk/qcom/clk-smd-rpm.c b/drivers/clk/qcom/clk-smd-rpm.c
> index ecacfbc4a16c..cce7daa97c1e 100644
> --- a/drivers/clk/qcom/clk-smd-rpm.c
> +++ b/drivers/clk/qcom/clk-smd-rpm.c
> @@ -438,6 +438,7 @@ static const struct clk_ops clk_smd_rpm_ops = {
>   	.round_rate	= clk_smd_rpm_round_rate,
>   	.recalc_rate	= clk_smd_rpm_recalc_rate,
>   	.is_enabled	= clk_smd_rpm_is_enabled,
> +	.is_prepared	= clk_smd_rpm_is_enabled,

I still suppose that prepared and enabled statuses should be handled 
separately. Otherwise CCF might get confused about prepared-but-enabled 
clocks. With this patch in place, it will treat them as being not prepared.

>   };
>   
>   static const struct clk_ops clk_smd_rpm_branch_ops = {
> @@ -445,6 +446,7 @@ static const struct clk_ops clk_smd_rpm_branch_ops = {
>   	.unprepare	= clk_smd_rpm_unprepare,
>   	.recalc_rate	= clk_smd_rpm_recalc_rate,
>   	.is_enabled	= clk_smd_rpm_is_enabled,
> +	.is_prepared	= clk_smd_rpm_is_enabled,
>   };
>   
>   DEFINE_CLK_SMD_RPM_BRANCH_A(bi_tcxo, QCOM_SMD_RPM_MISC_CLK, 0, 19200000);

-- 
With best wishes
Dmitry