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Message-ID: <42b1167d-da60-f6c3-67b6-3f6857327396@linaro.org>
Date:   Wed, 28 Jun 2023 19:18:45 +0200
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Subject: Re: [PATCH 2/2] clk: qcom: gdsc: Add support for set_hwmode_dev
Content-Language: en-US
To:     Abel Vesa <abel.vesa@linaro.org>,
        "Rafael J . Wysocki" <rafael@kernel.org>,
        Kevin Hilman <khilman@kernel.org>,
        Ulf Hansson <ulf.hansson@linaro.org>,
        avel Machek <pavel@ucw.cz>, Len Brown <len.brown@intel.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Bjorn Andersson <andersson@kernel.org>,
        Andy Gross <agross@kernel.org>,
        Mike Turquette <mturquette@baylibre.com>,
        Stephen Boyd <sboyd@kernel.org>,
        Taniya Das <tdas@qti.qualcomm.com>
Cc:     linux-pm@vger.kernel.org,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        linux-arm-msm@vger.kernel.org
References: <20230628105652.1670316-1-abel.vesa@linaro.org>
 <20230628105652.1670316-3-abel.vesa@linaro.org>
From:   Konrad Dybcio <konrad.dybcio@linaro.org>
In-Reply-To: <20230628105652.1670316-3-abel.vesa@linaro.org>
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Precedence: bulk

On 28.06.2023 12:56, Abel Vesa wrote:
> Implement the GDSC specific genpd set_hwmode_dev callback in order to
> switch the HW control on or off. For any GDSC that supports HW control
> set this callback in order to allow its consumers to control it.
> 
> Signed-off-by: Abel Vesa <abel.vesa@linaro.org>
> ---
This still does nothing to prevent the HW_CTRL state being changed in
init, enable and disable functions.

Konrad
>  drivers/clk/qcom/gdsc.c | 22 ++++++++++++++++++++++
>  1 file changed, 22 insertions(+)
> 
> diff --git a/drivers/clk/qcom/gdsc.c b/drivers/clk/qcom/gdsc.c
> index 5358e28122ab..9a04bf2e4379 100644
> --- a/drivers/clk/qcom/gdsc.c
> +++ b/drivers/clk/qcom/gdsc.c
> @@ -314,6 +314,26 @@ static int gdsc_enable(struct generic_pm_domain *domain)
>  	return 0;
>  }
>  
> +static int gdsc_set_hwmode_dev(struct generic_pm_domain *domain,
> +			       struct device *dev, bool enable)
> +{
> +	int ret = gdsc_hwctrl(domain_to_gdsc(domain), enable);
> +
> +	if (ret)
> +		goto out;
> +
> +	/*
> +	 * Wait for the GDSC to go through a power down and
> +	 * up cycle.  In case there is a status polling going on
> +	 * before the power cycle is completed it might read an
> +	 * wrong status value.
> +	 */
> +	udelay(1);
> +
> +out:
> +	return ret;
> +}
> +
>  static int gdsc_disable(struct generic_pm_domain *domain)
>  {
>  	struct gdsc *sc = domain_to_gdsc(domain);
> @@ -451,6 +471,8 @@ static int gdsc_init(struct gdsc *sc)
>  		sc->pd.power_off = gdsc_disable;
>  	if (!sc->pd.power_on)
>  		sc->pd.power_on = gdsc_enable;
> +	if (sc->flags & HW_CTRL)
> +		sc->pd.set_hwmode_dev = gdsc_set_hwmode_dev;
>  
>  	ret = pm_genpd_init(&sc->pd, NULL, !on);
>  	if (ret)