linux-kernel - Re: [PATCH 2/2] PM / OPP: Multiple regulators aren't supported yet

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:   Mon, 26 Sep 2016 10:37:56 +0530
From:   Viresh Kumar <viresh.kumar@...aro.org>
To:     Rob Herring <robh@...nel.org>
Cc:     Rafael Wysocki <rjw@...ysocki.net>,
        Viresh Kumar <vireshk@...nel.org>, Nishanth Menon <nm@...com>,
        Stephen Boyd <sboyd@...eaurora.org>,
        linaro-kernel@...ts.linaro.org, linux-pm@...r.kernel.org,
        linux-kernel@...r.kernel.org,
        Vincent Guittot <vincent.guittot@...aro.org>,
        devicetree@...r.kernel.org
Subject: Re: [PATCH 2/2] PM / OPP: Multiple regulators aren't supported yet

On 23-09-16, 14:59, Rob Herring wrote:
> On Wed, Sep 21, 2016 at 03:02:50PM +0530, Viresh Kumar wrote:
> > Multiple regulators per device aren't supported yet by the kernel code
> > and the bindings provided in documentation aren't sufficient to handle
> > that case (as there is no way for kernel code to link multiple
> > voltage/current values to a power supply).
> 
> What do you mean? Because the supplies are in the cpu node?

Not just that. For example if two supplies are present in CPU node like:
ABC-supply and XYZ-supply. And the values present in OPP node are like:

               opp00 {
                       opp-hz = /bits/ 64 <1700000000>;
                        /*                     ABC supply                XYZ        supply */
                       opp-microvolt = <1300000 1300000 1300000>, <1400000 1400000 1400000>;
                       opp-microamp = <70000>;
                       clock-latency-ns = <30>;
                       opp-suspend;
               };


Then the code can get regulators with those names (ABC and XYZ), but it can't
figure out which triplet in the "opp-microvolt" property belongs to which
supply.

I am working on some solution to that, but wanted to keep the entire series self
sufficient and so removing the leftovers first in this patch.

-- 
viresh