Re: [PATCH v2 2/6] mfd: lm3533: Convert to use OF bindings

[Svyatoslav Ryhel]

чт, 28 трав. 2026 р. о 17:50 Jonathan Cameron <jic23@xxxxxxxxxx> пише:
>
> On Thu, 28 May 2026 16:51:19 +0300
> Svyatoslav Ryhel <clamor95@xxxxxxxxx> wrote:
>
> > Since there are no users of this driver via platform data, remove the
> > platform data support and switch to using Device Tree bindings.
> > Additionally, optimize functions used only by platform data.
>
>
> At least the IIO ones would have made much the same amount of sense for
> dt, just that they weren't having in the first place. I'd prefer that
> as a precursor patch to make the rest much more readable.
>

I can add you preferences into this commit, I don't mind.

> >
> > Signed-off-by: Svyatoslav Ryhel <clamor95@xxxxxxxxx>
>
> I only looked in detail at the iio bit. A few changes requested.
>
> > ---
> >  drivers/iio/light/lm3533-als.c      |  95 ++++------
> >  drivers/leds/leds-lm3533.c          |  51 ++++--
> >  drivers/mfd/lm3533-core.c           | 268 ++++++++++------------------
> >  drivers/video/backlight/lm3533_bl.c |  52 ++++--
> >  include/linux/mfd/lm3533.h          |  51 +-----
> >  5 files changed, 212 insertions(+), 305 deletions(-)
> >
> > diff --git a/drivers/iio/light/lm3533-als.c b/drivers/iio/light/lm3533-als.c
> > index 99f0b903018c..cbd337b73bd9 100644
> > --- a/drivers/iio/light/lm3533-als.c
> > +++ b/drivers/iio/light/lm3533-als.c
>
> > @@ -714,59 +720,33 @@ static const struct attribute_group lm3533_als_attribute_group = {
> >       .attrs = lm3533_als_attributes
> >  };
> >
> > -static int lm3533_als_set_input_mode(struct lm3533_als *als, bool pwm_mode)
> > +static int lm3533_als_setup(struct lm3533_als *als)
> >  {
> > -     u8 mask = LM3533_ALS_INPUT_MODE_MASK;
> > -     u8 val;
> > +     struct device *dev = &als->pdev.dev;
> >       int ret;
> >
> > -     if (pwm_mode)
> > -             val = mask;     /* pwm input */
> > -     else
> > -             val = 0;        /* analog input */
> > -
> > -     ret = lm3533_update(als->lm3533, LM3533_REG_ALS_CONF, val, mask);
> > -     if (ret) {
> > -             dev_err(&als->pdev->dev, "failed to set input mode %d\n",
> > -                                                             pwm_mode);
> > -             return ret;
> > -     }
> > -
> > -     return 0;
> > -}
> > -
> > -static int lm3533_als_set_resistor(struct lm3533_als *als, u8 val)
> > -{
> > -     int ret;
> > -
> > -     if (val < LM3533_ALS_RESISTOR_MIN || val > LM3533_ALS_RESISTOR_MAX) {
> > -             dev_err(&als->pdev->dev, "invalid resistor value\n");
> > -             return -EINVAL;
> > -     }
> > -
> > -     ret = lm3533_write(als->lm3533, LM3533_REG_ALS_RESISTOR_SELECT, val);
> > -     if (ret) {
> > -             dev_err(&als->pdev->dev, "failed to set resistor\n");
> > -             return ret;
> > -     }
> > +     device_property_read_u32(dev, "ti,resistor-value-ohm",
> > +                              &als->r_select);
> Does this have a default?  If so the pattern we've recently be setting on for IIO
> is
>         if (device_property_present(dev, "ti,resistor-value-ohm"))
>                 ret = device_property_read_u32();
>                 if (ret) //corrupt property in some fashion
>                         return ret;
>         } else {
>                 //set default
>         }
> If there is no default then check it unconditionally.

default value is LM3533_ALS_RESISTOR_MIN and if no property is present
clamp will ensure that als->r_select will be set to
LM3533_ALS_RESISTOR_MIN

>
> >
> > -     return 0;
> > -}
> > +     als->r_select = clamp(als->r_select, LM3533_ALS_RESISTOR_MIN,
> > +                           LM3533_ALS_RESISTOR_MAX);
> > +     als->r_select = DIV_ROUND_UP(2 * MICRO, 10 * als->r_select);
> >
> > -static int lm3533_als_setup(struct lm3533_als *als,
> > -                         const struct lm3533_als_platform_data *pdata)
> > -{
> > -     int ret;
> > +     als->pwm_mode = device_property_read_bool(dev, "ti,pwm-mode");
> >
> > -     ret = lm3533_als_set_input_mode(als, pdata->pwm_mode);
> > +     ret = lm3533_update(lm3533, LM3533_REG_ALS_CONF, als->pwm_mode ?
> > +                         LM3533_ALS_INPUT_MODE_MASK : 0,
>
> That's ugly.  Better as
>
>         ret = lm3533_update(lm3533, LM3533_REG_ALS_CONF,
>                             als->pwm_mode ? LM3533_ALS_INPUT_MODE_MASK : 0,
>

Yes sure, just followed 80 char limit.

> Though if there wasn't a layer hiding the regmap, it could just have been
>
>         ret = regmap_assign_bits(lm3533->regmap, LM3533_REG_ALS_CONF,
>                                  LM3533_ALS_INPUT_MODE_MASK, als->pwm_mode);;
>
> which would have been nicer.
>
> I'm not particularly keen on the swashing of the helpers being in a patch
> that is about switching the binding type as feels largely unrelated.
> Should really have been a precursor, easier to review patch.
>

Removing of lm3533_update layer is not the scope of this patchset.

>
> > +                         LM3533_ALS_INPUT_MODE_MASK);
> >       if (ret)
> > -             return ret;
> > +             return dev_err_probe(dev, ret, "failed to set input mode %d\n",
> > +                                  als->pwm_mode);
> >
> >       /* ALS input is always high impedance in PWM-mode. */
> > -     if (!pdata->pwm_mode) {
> > -             ret = lm3533_als_set_resistor(als, pdata->r_select);
> > +     if (!als->pwm_mode) {
> > +             ret = lm3533_write(lm3533, LM3533_REG_ALS_RESISTOR_SELECT,
> > +                                (u8)als->r_select);
>
> Same applies here. Mostly an unrelated change as the only thing switching that
> is related to the patch is one parameter.
>

Removing of lm3533_write layer is not the scope of this patchset.

> >               if (ret)
> > -                     return ret;
> > +                     return dev_err_probe(dev, ret, "failed to set resistor\n");
> >       }
> >
> >       return 0;
>
> > @@ -852,25 +825,28 @@ static int lm3533_als_probe(struct platform_device *pdev)
> >       indio_dev->channels = lm3533_als_channels;
> >       indio_dev->num_channels = ARRAY_SIZE(lm3533_als_channels);
> >       indio_dev->name = dev_name(&pdev->dev);
> > -     iio_device_set_parent(indio_dev, pdev->dev.parent);
>
> I'm not sure why this was there in the first place.  Hence not sure if it
> is safe to remove.
>

This is directly related to OF conversion. The iio_device_set_parent
bound indio_dev to parent, and it causes problems with OF now since
als output has its own node and binding it to parent if wrong. Same
story for backlight and leds btw.

>
> > diff --git a/drivers/leds/leds-lm3533.c b/drivers/leds/leds-lm3533.c
> > index 45795f2a1042..d707d43d5526 100644
> > --- a/drivers/leds/leds-lm3533.c
> > +++ b/drivers/leds/leds-lm3533.c
>
> >
> >       led->cb.dev = led->cdev.dev;
> >
> > -     ret = lm3533_led_setup(led, pdata);
> > +     device_property_read_u32(&pdev->dev, "led-max-microamp",
> > +                              &led->max_current);
>
> I'd prefer explicit setting of the default to be visible before this, or
> the property_present pattern I mention in the IIO review above.
>

clamp will ensure that led->max_current will be set to
LM3533_LED_MAX_CURRENT_MIN regardless if it it present

> > +     led->max_current = clamp(led->max_current, LM3533_LED_MAX_CURRENT_MIN,
> > +                              LM3533_LED_MAX_CURRENT_MAX);
>
> I didn't look any further (busy day!)