RE: [PATCH V4 2/2] iio: light: isl29018: add optional vdd/vdda regulator operation support

[Anson Huang <anson.huang@nxp.com>]

Hi, Phil

Best Regards!
Anson Huang

> -----Original Message-----
> From: Phil Reid [mailto:preid@electromag.com.au]
> Sent: 2018年12月11日 11:36
> To: Anson Huang <anson.huang@nxp.com>; jic23@kernel.org;
> knaack.h@gmx.de; lars@metafoo.de; pmeerw@pmeerw.net;
> robh+dt@kernel.org; mark.rutland@arm.com; linux-iio@vger.kernel.org;
> devicetree@vger.kernel.org; linux-kernel@vger.kernel.org;
> festevam@gmail.com
> Cc: dl-linux-imx <linux-imx@nxp.com>
> Subject: Re: [PATCH V4 2/2] iio: light: isl29018: add optional vdd/vdda
> regulator operation support
> 
> On 11/12/2018 11:24 am, Anson Huang wrote:
> > The light sensor's power supply could be controlled by regulator on
> > some platforms, such as i.MX6Q-SABRESD board, the light sensor
> > isl29023's power supply is controlled by a GPIO fixed regulator, need
> > to make sure the regulator is enabled before any operation of sensor,
> > this patch adds optional vdd/vdda regulator operation support.
> >
> > Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
> > ---
> > ChangeLog since V3:
> > 	- improve the error handling of devm_regulator_get_optional;
> > 	- make sure regulators are disabled in error path.
> > ---
> >   drivers/iio/light/isl29018.c | 83
> ++++++++++++++++++++++++++++++++++++++++++--
> >   1 file changed, 80 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/iio/light/isl29018.c
> > b/drivers/iio/light/isl29018.c index b45400f..a21652b 100644
> > --- a/drivers/iio/light/isl29018.c
> > +++ b/drivers/iio/light/isl29018.c
> > @@ -23,6 +23,7 @@
> >   #include <linux/mutex.h>
> >   #include <linux/delay.h>
> >   #include <linux/regmap.h>
> > +#include <linux/regulator/consumer.h>
> >   #include <linux/slab.h>
> >   #include <linux/iio/iio.h>
> >   #include <linux/iio/sysfs.h>
> > @@ -95,6 +96,8 @@ struct isl29018_chip {
> >   	struct isl29018_scale	scale;
> >   	int			prox_scheme;
> >   	bool			suspended;
> > +	struct regulator	*vdd_reg;
> > +	struct regulator	*vdda_reg;
> >   };
> >
> >   static int isl29018_set_integration_time(struct isl29018_chip *chip,
> > @@ -735,6 +738,34 @@ static int isl29018_probe(struct i2c_client
> > *client,
> >
> >   	mutex_init(&chip->lock);
> >
> > +	chip->vdd_reg = devm_regulator_get_optional(&client->dev, "vdd");
> > +	if (!IS_ERR(chip->vdd_reg)) {
> > +		err = regulator_enable(chip->vdd_reg);
> > +		if (err) {
> > +			dev_err(&client->dev, "failed to enable VDD regulator\n");
> > +			return err;
> > +		}
> > +	} else {
> > +		err = PTR_ERR(chip->vdd_reg);
> > +		if (err != -ENODEV)
> > +			return err;
> > +	}
> > +
> > +	chip->vdda_reg = devm_regulator_get_optional(&client->dev, "vdda");
> > +	if (!IS_ERR(chip->vdda_reg)) {
> > +		err = regulator_enable(chip->vdda_reg);
> > +		if (err) {
> > +			dev_err(&client->dev, "failed to enable VDDA regulator\n");
> > +			if (!IS_ERR(chip->vdd_reg))
> > +				regulator_disable(chip->vdd_reg);
> > +			return err;
> > +		}
> > +	} else {
> > +		err = PTR_ERR(chip->vdda_reg);
> > +		if (err != -ENODEV)
> > +			return err;
> maybe goto disable_regulators; to disable vdd.

Agree, I will use " goto disable_regulators;" in both here and upper regulator enable fail case.
Please help review V5, thanks.

Anson

> 
> > +	}
> > +
> >   	chip->type = dev_id;
> >   	chip->calibscale = 1;
> >   	chip->ucalibscale = 0;
> > @@ -747,12 +778,12 @@ static int isl29018_probe(struct i2c_client *client,
> >   	if (IS_ERR(chip->regmap)) {
> >   		err = PTR_ERR(chip->regmap);
> >   		dev_err(&client->dev, "regmap initialization fails: %d\n", err);
> > -		return err;
> > +		goto disable_regulators;
> >   	}
> >
> >   	err = isl29018_chip_init(chip);
> >   	if (err)
> > -		return err;
> > +		goto disable_regulators;
> >
> >   	indio_dev->info = isl29018_chip_info_tbl[dev_id].indio_info;
> >   	indio_dev->channels = isl29018_chip_info_tbl[dev_id].channels;
> > @@ -761,13 +792,24 @@ static int isl29018_probe(struct i2c_client *client,
> >   	indio_dev->dev.parent = &client->dev;
> >   	indio_dev->modes = INDIO_DIRECT_MODE;
> >
> > -	return devm_iio_device_register(&client->dev, indio_dev);
> > +	err = devm_iio_device_register(&client->dev, indio_dev);
> > +	if (!err)
> > +		return 0;
> > +
> > +disable_regulators:
> > +	if (!IS_ERR(chip->vdd_reg))
> > +		regulator_disable(chip->vdd_reg);
> > +	if (!IS_ERR(chip->vdda_reg))
> > +		regulator_disable(chip->vdda_reg);
> > +
> > +	return err;
> >   }
> >
> [snip]
> 
> --
> Regards
> Phil