Hi, Phil Best Regards! Anson Huang > -----Original Message----- > From: Phil Reid [mailto:preid@xxxxxxxxxxxxxxxxx] > Sent: 2018年12月11日 11:56 > To: Anson Huang <anson.huang@xxxxxxx>; jic23@xxxxxxxxxx; > knaack.h@xxxxxx; lars@xxxxxxxxxx; pmeerw@xxxxxxxxxx; > robh+dt@xxxxxxxxxx; mark.rutland@xxxxxxx; linux-iio@xxxxxxxxxxxxxxx; > devicetree@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; > festevam@xxxxxxxxx > Cc: dl-linux-imx <linux-imx@xxxxxxx> > Subject: Re: [PATCH V4 2/2] iio: light: isl29018: add optional vdd/vdda > regulator operation support > > G'day Anson, > > Just pulled up the datasheet for this chip. > > The absolute max for Vdda is speced as Vddd +/-0.5 With a note that Vdda > should be externally shorted to Vddd. The data sheet says vdda should be connected to vdd externally, then I think we should just use one regulator vdd, then it will be much easier for the driver, what do you think? Anson. > > > On 11/12/2018 11:43 am, Anson Huang wrote: > > Hi, Phil > > > > Best Regards! > > Anson Huang > > > >> -----Original Message----- > >> From: Phil Reid [mailto:preid@xxxxxxxxxxxxxxxxx] > >> Sent: 2018年12月11日 11:36 > >> To: Anson Huang <anson.huang@xxxxxxx>; jic23@xxxxxxxxxx; > >> knaack.h@xxxxxx; lars@xxxxxxxxxx; pmeerw@xxxxxxxxxx; > >> robh+dt@xxxxxxxxxx; mark.rutland@xxxxxxx; linux-iio@xxxxxxxxxxxxxxx; > >> devicetree@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; > >> festevam@xxxxxxxxx > >> Cc: dl-linux-imx <linux-imx@xxxxxxx> > >> 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@xxxxxxx> > >>> --- > >>> 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; > Not sure about this case at the call to enable failed so I think you only want > the first one to be disabled. > You could add another goto statement thou, see below. > > > >>> + } > >>> + } 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. > > Here its safe to call both as vdda_reg will be an error ptr. > > > > > 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); > >>> + > eg: extra label here. > Order is changed thou, which may be a problem. > It's in the reverse order to the enable, which is usually what you want but the > datasheet concerns above may be an issue. > > > disable_regulators: > if (!IS_ERR(chip->vdda_reg)) > regulator_disable(chip->vdda_reg); > disable_regulator_vdd: > if (!IS_ERR(chip->vdd_reg)) > regulator_disable(chip->vdd_reg); > > >>> + return err; > >>> } > >>> > >> [snip] > >> > > > > -- > Regards > Phil
