[PATCH V4 1/2] dt-bindings: iio: light: isl29018: update power supply name

[PATCH V4 1/2] dt-bindings: iio: light: isl29018: update power supply name

[Anson Huang]

According to datasheet, the isl29018 has "vddd/vdda" power
supply, and isl29023/isl29035 ONLY has "vdd" power supply,
update the power supply name with "vdd" and "vdda" according
to datasheet to cover all devices and avoid confusion.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
---
 Documentation/devicetree/bindings/iio/light/isl29018.txt | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/iio/light/isl29018.txt b/Documentation/devicetree/bindings/iio/light/isl29018.txt
index b9bbde3..36f737d 100644
--- a/Documentation/devicetree/bindings/iio/light/isl29018.txt
+++ b/Documentation/devicetree/bindings/iio/light/isl29018.txt
@@ -15,7 +15,9 @@ Optional properties:
   Refer to interrupt-controller/interrupts.txt for generic interrupt client
   node bindings.
 
-  - vcc-supply: phandle to the regulator that provides power to the sensor.
+  - vdd-supply: phandle to the regulator that provides vdd power to the sensor.
+
+  - vdda-supply: phandle to the regulator that provides vdda power to the sensor.
 
 Example:
 
-- 
2.7.4

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

[Anson Huang]

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;
+	}
+
 	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;
 }
 
 #ifdef CONFIG_PM_SLEEP
 static int isl29018_suspend(struct device *dev)
 {
 	struct isl29018_chip *chip = iio_priv(dev_get_drvdata(dev));
+	int ret;
 
 	mutex_lock(&chip->lock);
 
@@ -777,6 +819,22 @@ static int isl29018_suspend(struct device *dev)
 	 * So we do not have much to do here.
 	 */
 	chip->suspended = true;
+	if (!IS_ERR(chip->vdd_reg)) {
+		ret = regulator_disable(chip->vdd_reg);
+		if (ret) {
+			dev_err(dev, "failed to disable VDD regulator\n");
+			mutex_unlock(&chip->lock);
+			return ret;
+		}
+	}
+	if (!IS_ERR(chip->vdda_reg)) {
+		ret = regulator_disable(chip->vdda_reg);
+		if (ret) {
+			dev_err(dev, "failed to disable VDDA regulator\n");
+			mutex_unlock(&chip->lock);
+			return ret;
+		}
+	}
 
 	mutex_unlock(&chip->lock);
 
@@ -790,6 +848,25 @@ static int isl29018_resume(struct device *dev)
 
 	mutex_lock(&chip->lock);
 
+	if (!IS_ERR(chip->vdd_reg)) {
+		err = regulator_enable(chip->vdd_reg);
+		if (err) {
+			dev_err(dev, "failed to enable VDD regulator\n");
+			mutex_unlock(&chip->lock);
+			return err;
+		}
+	}
+	if (!IS_ERR(chip->vdda_reg)) {
+		err = regulator_enable(chip->vdda_reg);
+		if (err) {
+			dev_err(dev, "failed to enable VDDA regulator\n");
+			if (!IS_ERR(chip->vdd_reg))
+				regulator_disable(chip->vdd_reg);
+			mutex_unlock(&chip->lock);
+			return err;
+		}
+	}
+
 	err = isl29018_chip_init(chip);
 	if (!err)
 		chip->suspended = false;
-- 
2.7.4

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

[Phil Reid]

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.

> +	}
> +
>   	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

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

[Anson Huang]

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

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

[Phil Reid]

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.


On 11/12/2018 11:43 am, Anson Huang wrote:
> 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;
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

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

[Anson Huang]

Hi, Phil

Best Regards!
Anson Huang

> -----Original Message-----
> From: Phil Reid [mailto:preid@electromag.com.au]
> Sent: 2018年12月11日 11:56
> 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
> 
> 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@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;
> 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

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

[Phil Reid]

On 11/12/2018 12:29 pm, Anson Huang wrote:
>> 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?
> 

Yes I think that makes sense.



-- 
Regards
Phil