linux-kernel - Re: [PATCH v4 4/7] regulator: qcom

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Message-ID: <CAOCk7NrwYezbVyLKOZdxgGRVemKtBmHKP+fSO0a2p3bCPNdW3w@mail.gmail.com>
Date:   Mon, 17 Jun 2019 09:17:21 -0600
From:   Jeffrey Hugo <jeffrey.l.hugo@...il.com>
To:     Mark Brown <broonie@...nel.org>
Cc:     lgirdwood@...il.com, Andy Gross <agross@...nel.org>,
        Bjorn Andersson <bjorn.andersson@...aro.org>,
        Rob Herring <robh+dt@...nel.org>,
        Mark Rutland <mark.rutland@....com>,
        MSM <linux-arm-msm@...r.kernel.org>,
        lkml <linux-kernel@...r.kernel.org>, devicetree@...r.kernel.org
Subject: Re: [PATCH v4 4/7] regulator: qcom_spmi: Add support for PM8005

On Mon, Jun 17, 2019 at 9:05 AM Mark Brown <broonie@...nel.org> wrote:
>
> On Thu, Jun 13, 2019 at 02:25:53PM -0700, Jeffrey Hugo wrote:
>
> > +static int spmi_regulator_ftsmps426_set_voltage(struct regulator_dev *rdev,
> > +                                           unsigned selector)
> > +{
> > +     struct spmi_regulator *vreg = rdev_get_drvdata(rdev);
> > +     u8 buf[2];
> > +     int mV;
> > +
> > +     mV = spmi_regulator_common_list_voltage(rdev, selector) / 1000;
> > +
> > +     buf[0] = mV & 0xff;
> > +     buf[1] = mV >> 8;
> > +     return spmi_vreg_write(vreg, SPMI_FTSMPS426_REG_VOLTAGE_LSB, buf, 2);
> > +}
>
> This could just be a set_voltage_sel(), no need for it to be a
> set_voltage() operation....

This is a set_voltage_sel() in spmi_ftsmps426_ops.  Is the issue because this
function is "spmi_regulator_ftsmps426_set_voltage" and not
"spmi_regulator_ftsmps426_set_voltage_sel"?

>
> > +static int spmi_regulator_ftsmps426_get_voltage(struct regulator_dev *rdev)
> > +{
> > +     struct spmi_regulator *vreg = rdev_get_drvdata(rdev);
> > +     u8 buf[2];
> > +
> > +     spmi_vreg_read(vreg, SPMI_FTSMPS426_REG_VOLTAGE_LSB, buf, 2);
> > +
> > +     return (((unsigned int)buf[1] << 8) | (unsigned int)buf[0]) * 1000;
> > +}
>
> ...or if the conversion is this trivial why do the list_voltage() lookup
> above?

We already have code in the driver to convert a selector to the
voltage.  Why duplicate
that inline in spmi_regulator_ftsmps426_set_voltage?

>
> > +spmi_regulator_ftsmps426_set_mode(struct regulator_dev *rdev, unsigned int mode)
> > +{
> > +     struct spmi_regulator *vreg = rdev_get_drvdata(rdev);
> > +     u8 mask = SPMI_FTSMPS426_MODE_MASK;
> > +     u8 val;
> > +
> > +     switch (mode) {
> > +     case REGULATOR_MODE_NORMAL:
> > +             val = SPMI_FTSMPS426_MODE_HPM_MASK;
> > +             break;
> > +     case REGULATOR_MODE_FAST:
> > +             val = SPMI_FTSMPS426_MODE_AUTO_MASK;
> > +             break;
> > +     default:
> > +             val = SPMI_FTSMPS426_MODE_LPM_MASK;
> > +             break;
> > +     }
>
> This should validate, it shouldn't just translate invalid values into
> valid ones.

Validate what?  The other defines are REGULATOR_MODE_IDLE
and REGULATOR_MODE_STANDBY which correspond to the LPM
mode.  Or are you suggesting that regulator framework is going to pass
REGULATOR_MODE_INVALID to this operation?