linux-kernel - Re: [PATCH] opp: Provide a function for just setting bandwidth

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Date:   Fri, 26 May 2023 16:23:20 +0530
From:   Viresh Kumar <viresh.kumar@...aro.org>
To:     Konrad Dybcio <konrad.dybcio@...aro.org>
Cc:     Viresh Kumar <vireshk@...nel.org>, Nishanth Menon <nm@...com>,
        Stephen Boyd <sboyd@...nel.org>,
        "Rafael J. Wysocki" <rafael@...nel.org>,
        Marijn Suijten <marijn.suijten@...ainline.org>,
        linux-pm@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] opp: Provide a function for just setting bandwidth

On 26-05-23, 11:17, Konrad Dybcio wrote:
> Currently it's not possible to set just the bandwidth if the OPP
> describes other properties (required-opps, opp-hz etc.).
> 
> Introduce dev_pm_opp_set_bw() to solve this problem.

The OPP core (intentionally) doesn't provide any such interface for
freq, volt, bw, level, etc.

Setting just one of the properties for a device is potentially harmful and the
OPP must be set as a whole and so this isn't allowed. There is
dev_pm_opp_set_freq(), but it uses freq to just find the OPP and sets entire OPP
only.

Why should be break this for bw ?

-- 
viresh