Re: [PATCH 2/4] regulator: Add driver for MT6331 PMIC regulators

[AngeloGioacchino Del Regno]

Il 20/05/22 16:45, Mark Brown ha scritto:
> On Fri, May 20, 2022 at 03:33:03PM +0200, AngeloGioacchino Del Regno wrote:
>
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * Copyright (c) 2022 Collabora Ltd.
> > + * Author: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>
> > + *
>
> Please make the entire comment a C++ one so things look more
> intentional.

Will do.

> > +static const unsigned int ldo_volt_table10[] = {
> > +	1200000, 1300000, 1500000, 1800000,
> > +	1200000, 1300000, 1500000, 1800000,
> > +	1200000, 1300000, 1500000, 1800000,
> > +	1200000, 1300000, 1500000, 1800000,
> > +};
>
> So the top bits of the voltate selection field just get ignored?  Might
> be easier to just write the code to not include the top bits.

No, they're all valid values for real... but I guess that I can simplify
this voltage table by simply modifying the bitmask that we use for the
regulators that are using this table....

Example:

MT6331_LDO_S("ldo-vcamio", VCAM_IO,  ldo_volt_table10, MT6331_SYSLDO_CON3, 10,

	MT6331_SYSLDO_CON11, GENMASK(6, 3), MT6331_SYSLDO_CON3, GENMASK(1, 0),

	MT6331_EN_STATUS1, BIT(13)),

So for VCAM_IO it's CON11... we have VGP2, VGP3 using CON14, CON15, then there
are no more users for this table.
If I use GENMASK(4, 3), I can effectively leave only four voltage values in
ldo_volt_table10.

Also, I've just noticed a mistake on ldo-vmipi: that's supposed to have a mask
of GENMASK(5, 3), not (6, 3) - which is in turn also making me able to remove
the ldo_volt_table_3a.

Alright, will fix in the next one :))

> > +static int mt6331_get_status(struct regulator_dev *rdev)
> > +{
> > +	struct mt6331_regulator_info *info = rdev_get_drvdata(rdev);
> > +	u32 reg, en_mask, regval;
> > +	int ret;
> > +
> > +	if (info->qi > 0) {
> > +		reg = info->desc.enable_reg;
> > +		en_mask = info->qi;
>
> If the regulator doesn't have status readback it shouldn't provide a
> get_status() operation.

What I've understood is that when there's no "QI" flag, the enable register
will provide the regulator status (EN/DIS) acting like QI, that's why I've
added that if branch...

Anyway, I'll recheck this part before sending the next version!

> > +static int mt6331_ldo_set_mode(struct regulator_dev *rdev, unsigned int mode)
> > +{
> > +	int ret, val = 0;
> > +	struct mt6331_regulator_info *info = rdev_get_drvdata(rdev);
> > +
> > +	if (!info->modeset_mask) {
> > +		dev_err(&rdev->dev, "regulator %s doesn't support set_mode\n",
> > +			info->desc.name);
> > +		return -EINVAL;
> > +	}
>
> Just don't provide the operation for these regulators then.  That'll
> mean a separate ops struct but that's fine.

Oki, I'll add new ops then.

Thanks for the review!
P.S.: I'll obviously apply the same suggestions on mt6332-regulator as well.

Cheers,
Angelo