Re: [PATCH v1 2/2] iio: adc: add Nuvoton NCT720x ADC driver

[Jonathan Cameron <jic23@kernel.org>]

On Thu, 7 Nov 2024 08:41:21 +0800
Yu-Hsian Yang <j2anfernee@gmail.com> wrote:

> Dear Krzysztof Kozlowski,
> 
> Thank you for your response.
> 
> Krzysztof Kozlowski <krzk@kernel.org> 於 2024年11月6日 週三 下午9:41寫道：
> >
> > On 06/11/2024 03:39, Eason Yang wrote:  
> > > Add Nuvoton NCT7201/NCT7202 system voltage monitor 12-bit ADC driver
> > >
> > > NCT7201/NCT7202 supports up to 12 analog voltage monitor inputs and up to
> > > 4 SMBus addresses by ADDR pin. Meanwhile, ALERT# hardware event pins for
> > > independent alarm signals, and the all threshold values could be set for
> > > system protection without any timing delay. It also supports reset input
> > > RSTIN# to recover system from a fault condition.
> > >
> > > Currently, only single-edge mode conversion and threshold events support.
> > >
> > > Signed-off-by: Eason Yang <j2anfernee@gmail.com>  
> >
> > ...
> >  
> > > +
> > > +static int nct720x_probe(struct i2c_client *client)
> > > +{
> > > +     const struct i2c_device_id *id = i2c_client_get_device_id(client);
> > > +     struct nct720x_chip_info *chip;
> > > +     struct iio_dev *indio_dev;
> > > +     int ret;
> > > +     u32 tmp;
> > > +
> > > +     indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*chip));
> > > +     if (!indio_dev)
> > > +             return -ENOMEM;
> > > +     chip = iio_priv(indio_dev);
> > > +
> > > +     if (client->dev.of_node)
> > > +             chip->type = (enum nct720x_chips)device_get_match_data(&client->dev);
> > > +     else
> > > +             chip->type = i2c_match_id(nct720x_id, client)->driver_data;  
> >
> > I believe there is a I2C wrapper for above.
> >  
> 
> Got it.

Don't pass an enum value as data.  Pass a pointer to a structure that describes the particular
variant.  The 0 value which tends to end up in enums is an error for device_get_match_data.

> 
> > > +
> > > +     chip->vin_max = (chip->type == nct7201) ? NCT7201_VIN_MAX : NCT7202_VIN_MAX;
> > > +
> > > +     ret = of_property_read_u32(client->dev.of_node, "read-vin-data-size", &tmp);
> > > +     if (ret < 0) {
> > > +             pr_err("read-vin-data-size property not found\n");  
> >
> > Please use dev_xxx in your driver code.  
> 
> Got it.
> 
> >
> >
> > Best regards,
> > Krzysztof
> >