[v5,1/9] iio: temp: ltc2983: Use __free(fwnode_handle) and device_for_each_node_scoped()

Commit Message

Jonathan Cameron Feb. 24, 2024, 12:32 p.m. UTC

From: Jonathan Cameron <[e-mail]>

This use of the new cleanup.h scope based freeing infrastructure allows
us to exit directly from error conditions and in the good path with
the reference obtained from fwnode_find_reference() (which may be an error
pointer) automatically released.

Similarly the _scoped() version of device_for_each_child_node()
removes the need for the manual calling of fwnode_handl_put() in
paths where the code exits the loop early.

Tidy up some unusual indentation in a dev_dbg() whilst here.

Cc: Cosmin Tanislav <[e-mail]>
Cc: Nuno Sá <[e-mail]>
Signed-off-by: Jonathan Cameron <[e-mail]>

---
v5: Add the device_for_each_child_node_scoped() change (Nuno)
---
 drivers/iio/temperature/ltc2983.c | 137 +++++++++++-------------------
 1 file changed, 50 insertions(+), 87 deletions(-)

Comments

Nuno Sá Feb. 26, 2024, 8:35 a.m. UTC | #1

On Sat, 2024-02-24 at 12:32 +0000, Jonathan Cameron wrote:
> From: Jonathan Cameron <[e-mail]>
> 
> This use of the new cleanup.h scope based freeing infrastructure allows
> us to exit directly from error conditions and in the good path with
> the reference obtained from fwnode_find_reference() (which may be an error
> pointer) automatically released.
> 
> Similarly the _scoped() version of device_for_each_child_node()
> removes the need for the manual calling of fwnode_handl_put() in
> paths where the code exits the loop early.
> 
> Tidy up some unusual indentation in a dev_dbg() whilst here.
> 
> Cc: Cosmin Tanislav <[e-mail]>
> Cc: Nuno Sá <[e-mail]>
> Signed-off-by: Jonathan Cameron <[e-mail]>
> 
> ---
> v5: Add the device_for_each_child_node_scoped() change (Nuno)
> ---

Reviewed-by: Nuno Sa <[e-mail]>

>  drivers/iio/temperature/ltc2983.c | 137 +++++++++++-------------------
>  1 file changed, 50 insertions(+), 87 deletions(-)
> 
> diff --git a/drivers/iio/temperature/ltc2983.c b/drivers/iio/temperature/ltc2983.c
> index fcb96c44d954..7d5473e7b500 100644
> --- a/drivers/iio/temperature/ltc2983.c
> +++ b/drivers/iio/temperature/ltc2983.c
> @@ -656,7 +656,6 @@ ltc2983_thermocouple_new(const struct fwnode_handle *child,
> struct ltc2983_data
>  			 const struct ltc2983_sensor *sensor)
>  {
>  	struct ltc2983_thermocouple *thermo;
> -	struct fwnode_handle *ref;
>  	u32 oc_current;
>  	int ret;
>  
> @@ -703,7 +702,8 @@ ltc2983_thermocouple_new(const struct fwnode_handle *child,
> struct ltc2983_data
>  		return ERR_PTR(-EINVAL);
>  	}
>  
> -	ref = fwnode_find_reference(child, "adi,cold-junction-handle", 0);
> +	struct fwnode_handle *ref __free(fwnode_handle) =
> +		fwnode_find_reference(child, "adi,cold-junction-handle", 0);
>  	if (IS_ERR(ref)) {
>  		ref = NULL;
>  	} else {
> @@ -714,7 +714,7 @@ ltc2983_thermocouple_new(const struct fwnode_handle *child,
> struct ltc2983_data
>  			 * the error right away.
>  			 */
>  			dev_err(&st->spi->dev, "Property reg must be given\n");
> -			goto fail;
> +			return ERR_PTR(ret);
>  		}
>  	}
>  
> @@ -725,22 +725,15 @@ ltc2983_thermocouple_new(const struct fwnode_handle *child,
> struct ltc2983_data
>  		thermo->custom = __ltc2983_custom_sensor_new(st, child,
>  							     propname, false,
>  							     16384, true);
> -		if (IS_ERR(thermo->custom)) {
> -			ret = PTR_ERR(thermo->custom);
> -			goto fail;
> -		}
> +		if (IS_ERR(thermo->custom))
> +			return ERR_CAST(thermo->custom);
>  	}
>  
>  	/* set common parameters */
>  	thermo->sensor.fault_handler = ltc2983_thermocouple_fault_handler;
>  	thermo->sensor.assign_chan = ltc2983_thermocouple_assign_chan;
>  
> -	fwnode_handle_put(ref);
>  	return &thermo->sensor;
> -
> -fail:
> -	fwnode_handle_put(ref);
> -	return ERR_PTR(ret);
>  }
>  
>  static struct ltc2983_sensor *
> @@ -750,14 +743,14 @@ ltc2983_rtd_new(const struct fwnode_handle *child, struct
> ltc2983_data *st,
>  	struct ltc2983_rtd *rtd;
>  	int ret = 0;
>  	struct device *dev = &st->spi->dev;
> -	struct fwnode_handle *ref;
>  	u32 excitation_current = 0, n_wires = 0;
>  
>  	rtd = devm_kzalloc(dev, sizeof(*rtd), GFP_KERNEL);
>  	if (!rtd)
>  		return ERR_PTR(-ENOMEM);
>  
> -	ref = fwnode_find_reference(child, "adi,rsense-handle", 0);
> +	struct fwnode_handle *ref __free(fwnode_handle) =
> +		fwnode_find_reference(child, "adi,rsense-handle", 0);
>  	if (IS_ERR(ref)) {
>  		dev_err(dev, "Property adi,rsense-handle missing or invalid");
>  		return ERR_CAST(ref);
> @@ -766,7 +759,7 @@ ltc2983_rtd_new(const struct fwnode_handle *child, struct
> ltc2983_data *st,
>  	ret = fwnode_property_read_u32(ref, "reg", &rtd->r_sense_chan);
>  	if (ret) {
>  		dev_err(dev, "Property reg must be given\n");
> -		goto fail;
> +		return ERR_PTR(ret);
>  	}
>  
>  	ret = fwnode_property_read_u32(child, "adi,number-of-wires", &n_wires);
> @@ -787,8 +780,7 @@ ltc2983_rtd_new(const struct fwnode_handle *child, struct
> ltc2983_data *st,
>  			break;
>  		default:
>  			dev_err(dev, "Invalid number of wires:%u\n", n_wires);
> -			ret = -EINVAL;
> -			goto fail;
> +			return ERR_PTR(-EINVAL);
>  		}
>  	}
>  
> @@ -798,8 +790,7 @@ ltc2983_rtd_new(const struct fwnode_handle *child, struct
> ltc2983_data *st,
>  			if (n_wires == 2 || n_wires == 3) {
>  				dev_err(dev,
>  					"Rotation not allowed for 2/3 Wire RTDs");
> -				ret = -EINVAL;
> -				goto fail;
> +				return ERR_PTR(-EINVAL);
>  			}
>  			rtd->sensor_config |= LTC2983_RTD_C_ROTATE(1);
>  		} else {
> @@ -829,16 +820,14 @@ ltc2983_rtd_new(const struct fwnode_handle *child, struct
> ltc2983_data *st,
>  				"Invalid rsense chann:%d to use in kelvin rsense",
>  				rtd->r_sense_chan);
>  
> -			ret = -EINVAL;
> -			goto fail;
> +			return ERR_PTR(-EINVAL);
>  		}
>  
>  		if (sensor->chan < min || sensor->chan > max) {
>  			dev_err(dev, "Invalid chann:%d for the rtd config",
>  				sensor->chan);
>  
> -			ret = -EINVAL;
> -			goto fail;
> +			return ERR_PTR(-EINVAL);
>  		}
>  	} else {
>  		/* same as differential case */
> @@ -846,8 +835,7 @@ ltc2983_rtd_new(const struct fwnode_handle *child, struct
> ltc2983_data *st,
>  			dev_err(&st->spi->dev,
>  				"Invalid chann:%d for RTD", sensor->chan);
>  
> -			ret = -EINVAL;
> -			goto fail;
> +			return ERR_PTR(-EINVAL);
>  		}
>  	}
>  
> @@ -856,10 +844,8 @@ ltc2983_rtd_new(const struct fwnode_handle *child, struct
> ltc2983_data *st,
>  		rtd->custom = __ltc2983_custom_sensor_new(st, child,
>  							  "adi,custom-rtd",
>  							  false, 2048, false);
> -		if (IS_ERR(rtd->custom)) {
> -			ret = PTR_ERR(rtd->custom);
> -			goto fail;
> -		}
> +		if (IS_ERR(rtd->custom))
> +			return ERR_CAST(rtd->custom);
>  	}
>  
>  	/* set common parameters */
> @@ -901,18 +887,13 @@ ltc2983_rtd_new(const struct fwnode_handle *child, struct
> ltc2983_data *st,
>  			dev_err(&st->spi->dev,
>  				"Invalid value for excitation current(%u)",
>  				excitation_current);
> -			ret = -EINVAL;
> -			goto fail;
> +			return ERR_PTR(-EINVAL);
>  		}
>  	}
>  
>  	fwnode_property_read_u32(child, "adi,rtd-curve", &rtd->rtd_curve);
>  
> -	fwnode_handle_put(ref);
>  	return &rtd->sensor;
> -fail:
> -	fwnode_handle_put(ref);
> -	return ERR_PTR(ret);
>  }
>  
>  static struct ltc2983_sensor *
> @@ -921,7 +902,6 @@ ltc2983_thermistor_new(const struct fwnode_handle *child,
> struct ltc2983_data *s
>  {
>  	struct ltc2983_thermistor *thermistor;
>  	struct device *dev = &st->spi->dev;
> -	struct fwnode_handle *ref;
>  	u32 excitation_current = 0;
>  	int ret = 0;
>  
> @@ -929,7 +909,8 @@ ltc2983_thermistor_new(const struct fwnode_handle *child,
> struct ltc2983_data *s
>  	if (!thermistor)
>  		return ERR_PTR(-ENOMEM);
>  
> -	ref = fwnode_find_reference(child, "adi,rsense-handle", 0);
> +	struct fwnode_handle *ref __free(fwnode_handle) =
> +		fwnode_find_reference(child, "adi,rsense-handle", 0);
>  	if (IS_ERR(ref)) {
>  		dev_err(dev, "Property adi,rsense-handle missing or invalid");
>  		return ERR_CAST(ref);
> @@ -938,7 +919,7 @@ ltc2983_thermistor_new(const struct fwnode_handle *child,
> struct ltc2983_data *s
>  	ret = fwnode_property_read_u32(ref, "reg", &thermistor->r_sense_chan);
>  	if (ret) {
>  		dev_err(dev, "rsense channel must be configured...\n");
> -		goto fail;
> +		return ERR_PTR(ret);
>  	}
>  
>  	if (fwnode_property_read_bool(child, "adi,single-ended")) {
> @@ -958,8 +939,7 @@ ltc2983_thermistor_new(const struct fwnode_handle *child,
> struct ltc2983_data *s
>  		dev_err(&st->spi->dev,
>  			"Invalid chann:%d for differential thermistor",
>  			sensor->chan);
> -		ret = -EINVAL;
> -		goto fail;
> +		return ERR_PTR(-EINVAL);
>  	}
>  
>  	/* check custom sensor */
> @@ -978,10 +958,8 @@ ltc2983_thermistor_new(const struct fwnode_handle *child,
> struct ltc2983_data *s
>  								 propname,
>  								 steinhart,
>  								 64, false);
> -		if (IS_ERR(thermistor->custom)) {
> -			ret = PTR_ERR(thermistor->custom);
> -			goto fail;
> -		}
> +		if (IS_ERR(thermistor->custom))
> +			return ERR_CAST(thermistor->custom);
>  	}
>  	/* set common parameters */
>  	thermistor->sensor.fault_handler = ltc2983_common_fault_handler;
> @@ -1005,8 +983,7 @@ ltc2983_thermistor_new(const struct fwnode_handle *child,
> struct ltc2983_data *s
>  			    LTC2983_SENSOR_THERMISTOR_STEINHART) {
>  				dev_err(&st->spi->dev,
>  					"Auto Range not allowed for custom
> sensors\n");
> -				ret = -EINVAL;
> -				goto fail;
> +				return ERR_PTR(-EINVAL);
>  			}
>  			thermistor->excitation_current = 0x0c;
>  			break;
> @@ -1047,16 +1024,11 @@ ltc2983_thermistor_new(const struct fwnode_handle *child,
> struct ltc2983_data *s
>  			dev_err(&st->spi->dev,
>  				"Invalid value for excitation current(%u)",
>  				excitation_current);
> -			ret = -EINVAL;
> -			goto fail;
> +			return ERR_PTR(-EINVAL);
>  		}
>  	}
>  
> -	fwnode_handle_put(ref);
>  	return &thermistor->sensor;
> -fail:
> -	fwnode_handle_put(ref);
> -	return ERR_PTR(ret);
>  }
>  
>  static struct ltc2983_sensor *
> @@ -1349,8 +1321,7 @@ static irqreturn_t ltc2983_irq_handler(int irq, void *data)
>  static int ltc2983_parse_dt(struct ltc2983_data *st)
>  {
>  	struct device *dev = &st->spi->dev;
> -	struct fwnode_handle *child;
> -	int ret = 0, chan = 0, channel_avail_mask = 0;
> +	int ret, chan = 0, channel_avail_mask = 0;
>  
>  	device_property_read_u32(dev, "adi,mux-delay-config-us", &st-
> >mux_delay_config);
>  
> @@ -1368,38 +1339,35 @@ static int ltc2983_parse_dt(struct ltc2983_data *st)
>  		return -ENOMEM;
>  
>  	st->iio_channels = st->num_channels;
> -	device_for_each_child_node(dev, child) {
> +	device_for_each_child_node_scoped(dev, child) {
>  		struct ltc2983_sensor sensor;
>  
>  		ret = fwnode_property_read_u32(child, "reg", &sensor.chan);
> -		if (ret) {
> -			dev_err(dev, "reg property must given for child nodes\n");
> -			goto put_child;
> -		}
> +		if (ret)
> +			return dev_err_probe(dev, ret,
> +				"reg property must given for child nodes\n");
>  
>  		/* check if we have a valid channel */
>  		if (sensor.chan < LTC2983_MIN_CHANNELS_NR ||
> -		    sensor.chan > st->info->max_channels_nr) {
> -			ret = -EINVAL;
> -			dev_err(dev, "chan:%d must be from %u to %u\n",
> sensor.chan,
> -				LTC2983_MIN_CHANNELS_NR, st->info-
> >max_channels_nr);
> -			goto put_child;
> -		} else if (channel_avail_mask & BIT(sensor.chan)) {
> -			ret = -EINVAL;
> -			dev_err(dev, "chan:%d already in use\n", sensor.chan);
> -			goto put_child;
> -		}
> +		    sensor.chan > st->info->max_channels_nr)
> +			return dev_err_probe(dev, -EINVAL,
> +					     "chan:%d must be from %u to %u\n",
> +					     sensor.chan,
> +					     LTC2983_MIN_CHANNELS_NR,
> +					     st->info->max_channels_nr);
> +
> +		if (channel_avail_mask & BIT(sensor.chan))
> +			return dev_err_probe(dev, -EINVAL,
> +					     "chan:%d already in use\n",
> +					     sensor.chan);
>  
>  		ret = fwnode_property_read_u32(child, "adi,sensor-type",
> &sensor.type);
> -		if (ret) {
> -			dev_err(dev,
> +		if (ret)
> +			return dev_err_probe(dev, ret,
>  				"adi,sensor-type property must given for child
> nodes\n");
> -			goto put_child;
> -		}
>  
>  		dev_dbg(dev, "Create new sensor, type %u, chann %u",
> -								sensor.type,
> -								sensor.chan);
> +			sensor.type, sensor.chan);
>  
>  		if (sensor.type >= LTC2983_SENSOR_THERMOCOUPLE &&
>  		    sensor.type <= LTC2983_SENSOR_THERMOCOUPLE_CUSTOM) {
> @@ -1426,17 +1394,15 @@ static int ltc2983_parse_dt(struct ltc2983_data *st)
>  			   sensor.type == LTC2983_SENSOR_ACTIVE_TEMP) {
>  			st->sensors[chan] = ltc2983_temp_new(child, st, &sensor);
>  		} else {
> -			dev_err(dev, "Unknown sensor type %d\n", sensor.type);
> -			ret = -EINVAL;
> -			goto put_child;
> +			return dev_err_probe(dev, -EINVAL,
> +					     "Unknown sensor type %d\n",
> +					     sensor.type);
>  		}
>  
> -		if (IS_ERR(st->sensors[chan])) {
> -			dev_err(dev, "Failed to create sensor %ld",
> -				PTR_ERR(st->sensors[chan]));
> -			ret = PTR_ERR(st->sensors[chan]);
> -			goto put_child;
> -		}
> +		if (IS_ERR(st->sensors[chan]))
> +			return dev_err_probe(dev, PTR_ERR(st->sensors[chan]),
> +					     "Failed to create sensor\n");
> +
>  		/* set generic sensor parameters */
>  		st->sensors[chan]->chan = sensor.chan;
>  		st->sensors[chan]->type = sensor.type;
> @@ -1446,9 +1412,6 @@ static int ltc2983_parse_dt(struct ltc2983_data *st)
>  	}
>  
>  	return 0;
> -put_child:
> -	fwnode_handle_put(child);
> -	return ret;
>  }
>  
>  static int ltc2983_eeprom_cmd(struct ltc2983_data *st, unsigned int cmd,

Jonathan Cameron Feb. 26, 2024, 7:30 p.m. UTC | #2

On Mon, 26 Feb 2024 09:35:49 +0100
Nuno Sá <[e-mail]> wrote:

> On Sat, 2024-02-24 at 12:32 +0000, Jonathan Cameron wrote:
> > From: Jonathan Cameron <[e-mail]>
> > 
> > This use of the new cleanup.h scope based freeing infrastructure allows
> > us to exit directly from error conditions and in the good path with
> > the reference obtained from fwnode_find_reference() (which may be an error
> > pointer) automatically released.
> > 
> > Similarly the _scoped() version of device_for_each_child_node()
> > removes the need for the manual calling of fwnode_handl_put() in
> > paths where the code exits the loop early.
> > 
> > Tidy up some unusual indentation in a dev_dbg() whilst here.
> > 
> > Cc: Cosmin Tanislav <[e-mail]>
> > Cc: Nuno Sá <[e-mail]>
> > Signed-off-by: Jonathan Cameron <[e-mail]>
> > 
> > ---
> > v5: Add the device_for_each_child_node_scoped() change (Nuno)
> > ---  
> 
> Reviewed-by: Nuno Sa <[e-mail]>
I'll pick up this now as whilst I hope someone will check the others, I know
you are building on this and it will make life easier if this is already
queued up.

Thanks,

Jonathan

Nuno Sá Feb. 27, 2024, 8:08 a.m. UTC | #3

On Mon, 2024-02-26 at 19:30 +0000, Jonathan Cameron wrote:
> On Mon, 26 Feb 2024 09:35:49 +0100
> Nuno Sá <[e-mail]> wrote:
> 
> > On Sat, 2024-02-24 at 12:32 +0000, Jonathan Cameron wrote:
> > > From: Jonathan Cameron <[e-mail]>
> > > 
> > > This use of the new cleanup.h scope based freeing infrastructure allows
> > > us to exit directly from error conditions and in the good path with
> > > the reference obtained from fwnode_find_reference() (which may be an error
> > > pointer) automatically released.
> > > 
> > > Similarly the _scoped() version of device_for_each_child_node()
> > > removes the need for the manual calling of fwnode_handl_put() in
> > > paths where the code exits the loop early.
> > > 
> > > Tidy up some unusual indentation in a dev_dbg() whilst here.
> > > 
> > > Cc: Cosmin Tanislav <[e-mail]>
> > > Cc: Nuno Sá <[e-mail]>
> > > Signed-off-by: Jonathan Cameron <[e-mail]>
> > > 
> > > ---
> > > v5: Add the device_for_each_child_node_scoped() change (Nuno)
> > > ---  
> > 
> > Reviewed-by: Nuno Sa <[e-mail]>
> I'll pick up this now as whilst I hope someone will check the others, I know
> you are building on this and it will make life easier if this is already
> queued up.
> 

Thanks,

Will work on top of that for my series.

- Nuno Sá

Patch

diff --git a/drivers/iio/temperature/ltc2983.c b/drivers/iio/temperature/ltc2983.c
index fcb96c44d954..7d5473e7b500 100644
--- a/drivers/iio/temperature/ltc2983.c
+++ b/drivers/iio/temperature/ltc2983.c
@@ -656,7 +656,6 @@  ltc2983_thermocouple_new(const struct fwnode_handle *child, struct ltc2983_data
 			 const struct ltc2983_sensor *sensor)
 {
 	struct ltc2983_thermocouple *thermo;
-	struct fwnode_handle *ref;
 	u32 oc_current;
 	int ret;
 
@@ -703,7 +702,8 @@  ltc2983_thermocouple_new(const struct fwnode_handle *child, struct ltc2983_data
 		return ERR_PTR(-EINVAL);
 	}
 
-	ref = fwnode_find_reference(child, "adi,cold-junction-handle", 0);
+	struct fwnode_handle *ref __free(fwnode_handle) =
+		fwnode_find_reference(child, "adi,cold-junction-handle", 0);
 	if (IS_ERR(ref)) {
 		ref = NULL;
 	} else {
@@ -714,7 +714,7 @@  ltc2983_thermocouple_new(const struct fwnode_handle *child, struct ltc2983_data
 			 * the error right away.
 			 */
 			dev_err(&st->spi->dev, "Property reg must be given\n");
-			goto fail;
+			return ERR_PTR(ret);
 		}
 	}
 
@@ -725,22 +725,15 @@  ltc2983_thermocouple_new(const struct fwnode_handle *child, struct ltc2983_data
 		thermo->custom = __ltc2983_custom_sensor_new(st, child,
 							     propname, false,
 							     16384, true);
-		if (IS_ERR(thermo->custom)) {
-			ret = PTR_ERR(thermo->custom);
-			goto fail;
-		}
+		if (IS_ERR(thermo->custom))
+			return ERR_CAST(thermo->custom);
 	}
 
 	/* set common parameters */
 	thermo->sensor.fault_handler = ltc2983_thermocouple_fault_handler;
 	thermo->sensor.assign_chan = ltc2983_thermocouple_assign_chan;
 
-	fwnode_handle_put(ref);
 	return &thermo->sensor;
-
-fail:
-	fwnode_handle_put(ref);
-	return ERR_PTR(ret);
 }
 
 static struct ltc2983_sensor *
@@ -750,14 +743,14 @@  ltc2983_rtd_new(const struct fwnode_handle *child, struct ltc2983_data *st,
 	struct ltc2983_rtd *rtd;
 	int ret = 0;
 	struct device *dev = &st->spi->dev;
-	struct fwnode_handle *ref;
 	u32 excitation_current = 0, n_wires = 0;
 
 	rtd = devm_kzalloc(dev, sizeof(*rtd), GFP_KERNEL);
 	if (!rtd)
 		return ERR_PTR(-ENOMEM);
 
-	ref = fwnode_find_reference(child, "adi,rsense-handle", 0);
+	struct fwnode_handle *ref __free(fwnode_handle) =
+		fwnode_find_reference(child, "adi,rsense-handle", 0);
 	if (IS_ERR(ref)) {
 		dev_err(dev, "Property adi,rsense-handle missing or invalid");
 		return ERR_CAST(ref);
@@ -766,7 +759,7 @@  ltc2983_rtd_new(const struct fwnode_handle *child, struct ltc2983_data *st,
 	ret = fwnode_property_read_u32(ref, "reg", &rtd->r_sense_chan);
 	if (ret) {
 		dev_err(dev, "Property reg must be given\n");
-		goto fail;
+		return ERR_PTR(ret);
 	}
 
 	ret = fwnode_property_read_u32(child, "adi,number-of-wires", &n_wires);
@@ -787,8 +780,7 @@  ltc2983_rtd_new(const struct fwnode_handle *child, struct ltc2983_data *st,
 			break;
 		default:
 			dev_err(dev, "Invalid number of wires:%u\n", n_wires);
-			ret = -EINVAL;
-			goto fail;
+			return ERR_PTR(-EINVAL);
 		}
 	}
 
@@ -798,8 +790,7 @@  ltc2983_rtd_new(const struct fwnode_handle *child, struct ltc2983_data *st,
 			if (n_wires == 2 || n_wires == 3) {
 				dev_err(dev,
 					"Rotation not allowed for 2/3 Wire RTDs");
-				ret = -EINVAL;
-				goto fail;
+				return ERR_PTR(-EINVAL);
 			}
 			rtd->sensor_config |= LTC2983_RTD_C_ROTATE(1);
 		} else {
@@ -829,16 +820,14 @@  ltc2983_rtd_new(const struct fwnode_handle *child, struct ltc2983_data *st,
 				"Invalid rsense chann:%d to use in kelvin rsense",
 				rtd->r_sense_chan);
 
-			ret = -EINVAL;
-			goto fail;
+			return ERR_PTR(-EINVAL);
 		}
 
 		if (sensor->chan < min || sensor->chan > max) {
 			dev_err(dev, "Invalid chann:%d for the rtd config",
 				sensor->chan);
 
-			ret = -EINVAL;
-			goto fail;
+			return ERR_PTR(-EINVAL);
 		}
 	} else {
 		/* same as differential case */
@@ -846,8 +835,7 @@  ltc2983_rtd_new(const struct fwnode_handle *child, struct ltc2983_data *st,
 			dev_err(&st->spi->dev,
 				"Invalid chann:%d for RTD", sensor->chan);
 
-			ret = -EINVAL;
-			goto fail;
+			return ERR_PTR(-EINVAL);
 		}
 	}
 
@@ -856,10 +844,8 @@  ltc2983_rtd_new(const struct fwnode_handle *child, struct ltc2983_data *st,
 		rtd->custom = __ltc2983_custom_sensor_new(st, child,
 							  "adi,custom-rtd",
 							  false, 2048, false);
-		if (IS_ERR(rtd->custom)) {
-			ret = PTR_ERR(rtd->custom);
-			goto fail;
-		}
+		if (IS_ERR(rtd->custom))
+			return ERR_CAST(rtd->custom);
 	}
 
 	/* set common parameters */
@@ -901,18 +887,13 @@  ltc2983_rtd_new(const struct fwnode_handle *child, struct ltc2983_data *st,
 			dev_err(&st->spi->dev,
 				"Invalid value for excitation current(%u)",
 				excitation_current);
-			ret = -EINVAL;
-			goto fail;
+			return ERR_PTR(-EINVAL);
 		}
 	}
 
 	fwnode_property_read_u32(child, "adi,rtd-curve", &rtd->rtd_curve);
 
-	fwnode_handle_put(ref);
 	return &rtd->sensor;
-fail:
-	fwnode_handle_put(ref);
-	return ERR_PTR(ret);
 }
 
 static struct ltc2983_sensor *
@@ -921,7 +902,6 @@  ltc2983_thermistor_new(const struct fwnode_handle *child, struct ltc2983_data *s
 {
 	struct ltc2983_thermistor *thermistor;
 	struct device *dev = &st->spi->dev;
-	struct fwnode_handle *ref;
 	u32 excitation_current = 0;
 	int ret = 0;
 
@@ -929,7 +909,8 @@  ltc2983_thermistor_new(const struct fwnode_handle *child, struct ltc2983_data *s
 	if (!thermistor)
 		return ERR_PTR(-ENOMEM);
 
-	ref = fwnode_find_reference(child, "adi,rsense-handle", 0);
+	struct fwnode_handle *ref __free(fwnode_handle) =
+		fwnode_find_reference(child, "adi,rsense-handle", 0);
 	if (IS_ERR(ref)) {
 		dev_err(dev, "Property adi,rsense-handle missing or invalid");
 		return ERR_CAST(ref);
@@ -938,7 +919,7 @@  ltc2983_thermistor_new(const struct fwnode_handle *child, struct ltc2983_data *s
 	ret = fwnode_property_read_u32(ref, "reg", &thermistor->r_sense_chan);
 	if (ret) {
 		dev_err(dev, "rsense channel must be configured...\n");
-		goto fail;
+		return ERR_PTR(ret);
 	}
 
 	if (fwnode_property_read_bool(child, "adi,single-ended")) {
@@ -958,8 +939,7 @@  ltc2983_thermistor_new(const struct fwnode_handle *child, struct ltc2983_data *s
 		dev_err(&st->spi->dev,
 			"Invalid chann:%d for differential thermistor",
 			sensor->chan);
-		ret = -EINVAL;
-		goto fail;
+		return ERR_PTR(-EINVAL);
 	}
 
 	/* check custom sensor */
@@ -978,10 +958,8 @@  ltc2983_thermistor_new(const struct fwnode_handle *child, struct ltc2983_data *s
 								 propname,
 								 steinhart,
 								 64, false);
-		if (IS_ERR(thermistor->custom)) {
-			ret = PTR_ERR(thermistor->custom);
-			goto fail;
-		}
+		if (IS_ERR(thermistor->custom))
+			return ERR_CAST(thermistor->custom);
 	}
 	/* set common parameters */
 	thermistor->sensor.fault_handler = ltc2983_common_fault_handler;
@@ -1005,8 +983,7 @@  ltc2983_thermistor_new(const struct fwnode_handle *child, struct ltc2983_data *s
 			    LTC2983_SENSOR_THERMISTOR_STEINHART) {
 				dev_err(&st->spi->dev,
 					"Auto Range not allowed for custom sensors\n");
-				ret = -EINVAL;
-				goto fail;
+				return ERR_PTR(-EINVAL);
 			}
 			thermistor->excitation_current = 0x0c;
 			break;
@@ -1047,16 +1024,11 @@  ltc2983_thermistor_new(const struct fwnode_handle *child, struct ltc2983_data *s
 			dev_err(&st->spi->dev,
 				"Invalid value for excitation current(%u)",
 				excitation_current);
-			ret = -EINVAL;
-			goto fail;
+			return ERR_PTR(-EINVAL);
 		}
 	}
 
-	fwnode_handle_put(ref);
 	return &thermistor->sensor;
-fail:
-	fwnode_handle_put(ref);
-	return ERR_PTR(ret);
 }
 
 static struct ltc2983_sensor *
@@ -1349,8 +1321,7 @@  static irqreturn_t ltc2983_irq_handler(int irq, void *data)
 static int ltc2983_parse_dt(struct ltc2983_data *st)
 {
 	struct device *dev = &st->spi->dev;
-	struct fwnode_handle *child;
-	int ret = 0, chan = 0, channel_avail_mask = 0;
+	int ret, chan = 0, channel_avail_mask = 0;
 
 	device_property_read_u32(dev, "adi,mux-delay-config-us", &st->mux_delay_config);
 
@@ -1368,38 +1339,35 @@  static int ltc2983_parse_dt(struct ltc2983_data *st)
 		return -ENOMEM;
 
 	st->iio_channels = st->num_channels;
-	device_for_each_child_node(dev, child) {
+	device_for_each_child_node_scoped(dev, child) {
 		struct ltc2983_sensor sensor;
 
 		ret = fwnode_property_read_u32(child, "reg", &sensor.chan);
-		if (ret) {
-			dev_err(dev, "reg property must given for child nodes\n");
-			goto put_child;
-		}
+		if (ret)
+			return dev_err_probe(dev, ret,
+				"reg property must given for child nodes\n");
 
 		/* check if we have a valid channel */
 		if (sensor.chan < LTC2983_MIN_CHANNELS_NR ||
-		    sensor.chan > st->info->max_channels_nr) {
-			ret = -EINVAL;
-			dev_err(dev, "chan:%d must be from %u to %u\n", sensor.chan,
-				LTC2983_MIN_CHANNELS_NR, st->info->max_channels_nr);
-			goto put_child;
-		} else if (channel_avail_mask & BIT(sensor.chan)) {
-			ret = -EINVAL;
-			dev_err(dev, "chan:%d already in use\n", sensor.chan);
-			goto put_child;
-		}
+		    sensor.chan > st->info->max_channels_nr)
+			return dev_err_probe(dev, -EINVAL,
+					     "chan:%d must be from %u to %u\n",
+					     sensor.chan,
+					     LTC2983_MIN_CHANNELS_NR,
+					     st->info->max_channels_nr);
+
+		if (channel_avail_mask & BIT(sensor.chan))
+			return dev_err_probe(dev, -EINVAL,
+					     "chan:%d already in use\n",
+					     sensor.chan);
 
 		ret = fwnode_property_read_u32(child, "adi,sensor-type", &sensor.type);
-		if (ret) {
-			dev_err(dev,
+		if (ret)
+			return dev_err_probe(dev, ret,
 				"adi,sensor-type property must given for child nodes\n");
-			goto put_child;
-		}
 
 		dev_dbg(dev, "Create new sensor, type %u, chann %u",
-								sensor.type,
-								sensor.chan);
+			sensor.type, sensor.chan);
 
 		if (sensor.type >= LTC2983_SENSOR_THERMOCOUPLE &&
 		    sensor.type <= LTC2983_SENSOR_THERMOCOUPLE_CUSTOM) {
@@ -1426,17 +1394,15 @@  static int ltc2983_parse_dt(struct ltc2983_data *st)
 			   sensor.type == LTC2983_SENSOR_ACTIVE_TEMP) {
 			st->sensors[chan] = ltc2983_temp_new(child, st, &sensor);
 		} else {
-			dev_err(dev, "Unknown sensor type %d\n", sensor.type);
-			ret = -EINVAL;
-			goto put_child;
+			return dev_err_probe(dev, -EINVAL,
+					     "Unknown sensor type %d\n",
+					     sensor.type);
 		}
 
-		if (IS_ERR(st->sensors[chan])) {
-			dev_err(dev, "Failed to create sensor %ld",
-				PTR_ERR(st->sensors[chan]));
-			ret = PTR_ERR(st->sensors[chan]);
-			goto put_child;
-		}
+		if (IS_ERR(st->sensors[chan]))
+			return dev_err_probe(dev, PTR_ERR(st->sensors[chan]),
+					     "Failed to create sensor\n");
+
 		/* set generic sensor parameters */
 		st->sensors[chan]->chan = sensor.chan;
 		st->sensors[chan]->type = sensor.type;
@@ -1446,9 +1412,6 @@  static int ltc2983_parse_dt(struct ltc2983_data *st)
 	}
 
 	return 0;
-put_child:
-	fwnode_handle_put(child);
-	return ret;
 }
 
 static int ltc2983_eeprom_cmd(struct ltc2983_data *st, unsigned int cmd,