RE: [PATCH v7 10/14] dt-bindings: qcom_spmi: Add support for SAW documentation

[<ilialin@codeaurora.org>]

> -----Original Message-----
> From: amit.kucheria@verdurent.com <amit.kucheria@verdurent.com> On
> Behalf Of Amit Kucheria
> Sent: Wednesday, May 16, 2018 16:13
> To: Ilia Lin <ilialin@codeaurora.org>
> Cc: Michael Turquette <mturquette@baylibre.com>; sboyd@kernel.org; Rob
> Herring <robh@kernel.org>; Mark Rutland <mark.rutland@arm.com>; Viresh
> Kumar <viresh.kumar@linaro.org>; nm@ti.com; lgirdwood@gmail.com;
> broonie@kernel.org; Andy Gross <andy.gross@linaro.org>; David Brown
> <david.brown@linaro.org>; catalin.marinas@arm.com;
> will.deacon@arm.com; Rafael J. Wysocki <rjw@rjwysocki.net>; linux-
> clk@vger.kernel.org; devicetree@vger.kernel.org; LKML <linux-
> kernel@vger.kernel.org>; Linux PM list <linux-pm@vger.kernel.org>; linux-
> arm-msm@vger.kernel.org; linux-soc@vger.kernel.org; lakml <linux-arm-
> kernel@lists.infradead.org>; Rajendra Nayak <rnayak@codeaurora.org>;
> nicolas.dechesne@linaro.org; celster@codeaurora.org;
> tfinkel@codeaurora.org
> Subject: Re: [PATCH v7 10/14] dt-bindings: qcom_spmi: Add support for SAW
> documentation
> 
> On Tue, May 15, 2018 at 12:13 PM, Ilia Lin <ilialin@codeaurora.org> wrote:
> > Add support for SAW controlled regulators.
> > The regulators defined as SAW controlled in the device tree will be
> > controlled through special CPU registers instead of direct SPMI
> > accesses.
> > This is required especially for CPU supply regulators to synchronize
> > with clock scaling and for Automatic Voltage Switching.
> > Document it.
> 
> Replace this boiler plate with what this patch actual does. Besides changing
> the subject, it could be, for example,
> 
> "Document the DT bindings for the SAW regulators.
> 
> The saw-slave property allows ganging (grouping) of several regulators so
> that their outputs can be combined... blah blah.
> 
> The saw-leader is the only one that then is configurable in DT"

Actually, I invested some fantasy to write this explanation. But I'll try to revise it.

> 
> 
> > Signed-off-by: Ilia Lin <ilialin@codeaurora.org>
> > Reviewed-by: Rob Herring <robh@kernel.org>
> > ---
> >  .../bindings/regulator/qcom,spmi-regulator.txt     | 45
> ++++++++++++++++++++++
> >  1 file changed, 45 insertions(+)
> >
> > diff --git
> > a/Documentation/devicetree/bindings/regulator/qcom,spmi-regulator.txt
> > b/Documentation/devicetree/bindings/regulator/qcom,spmi-regulator.txt
> > index 57d2c65..406f2e5 100644
> > ---
> > a/Documentation/devicetree/bindings/regulator/qcom,spmi-regulator.txt
> > +++ b/Documentation/devicetree/bindings/regulator/qcom,spmi-
> regulator.
> > +++ txt
> > @@ -110,6 +110,11 @@ Qualcomm SPMI Regulators
> >         Definition: Reference to regulator supplying the input pin, as
> >                     described in the data sheet.
> >
> > +- qcom,saw-reg:
> > +       Usage: optional
> > +       Value type: <phandle>
> > +       Description: Reference to syscon node defining the SAW registers.
> > +
> >
> >  The regulator node houses sub-nodes for each regulator within the
> > device. Each  sub-node is identified using the node's name, with valid
> > values listed for each @@ -201,6 +206,17 @@ see regulator.txt - with
> additional custom properties described below:
> >                         2 = 0.55 uA
> >                         3 = 0.75 uA
> >
> > +- qcom,saw-slave:
> > +       Usage: optional
> > +       Value type: <boo>
> > +       Description: SAW controlled gang slave. Will not be configured.
> > +
> > +- qcom,saw-leader:
> > +       Usage: optional
> > +       Value type: <boo>
> > +       Description: SAW controlled gang leader. Will be configured as
> > +                    SAW regulator.
> > +
> >  Example:
> >
> >         regulators {
> > @@ -221,3 +237,32 @@ Example:
> >
> >                 ....
> >         };
> > +
> > +Example 2:
> > +
> > +       saw3: syscon@9A10000 {
> > +               compatible = "syscon";
> > +               reg = <0x9A10000 0x1000>;
> > +       };
> > +
> > +       ...
> > +
> > +       spm-regulators {
> > +               compatible = "qcom,pm8994-regulators";
> > +               qcom,saw-reg = <&saw3>;
> > +               s8 {
> > +                       qcom,saw-slave;
> > +               };
> > +               s9 {
> > +                       qcom,saw-slave;
> > +               };
> > +               s10 {
> > +                       qcom,saw-slave;
> > +               };
> > +               pm8994_s11_saw: s11 {
> > +                       qcom,saw-leader;
> > +                       regulator-always-on;
> > +                       regulator-min-microvolt = <900000>;
> > +                       regulator-max-microvolt = <1140000>;
> > +               };
> > +       };
> > --
> > 1.9.1
> >