[PATCH v4 2/6] iio: temperature: ltc2983: convert to dev_err_probe()

From: Nuno Sa via B4 Relay
Date: Thu Mar 28 2024 - 12:23:06 EST

From: Nuno Sa <nuno.sa@xxxxxxxxxx>

Use dev_err_probe() in the probe() path. While at it, made some simple
improvements:
* Declare a struct device *dev helper. This also makes the style more
consistent (some places the helper was used and not in other places);
* Explicitly included the err.h and errno.h headers;
* Removed an useless else if();
* Removed some unnecessary line breaks.

Signed-off-by: Nuno Sa <nuno.sa@xxxxxxxxxx>
---
drivers/iio/temperature/ltc2983.c | 255 +++++++++++++++++---------------------
1 file changed, 115 insertions(+), 140 deletions(-)

diff --git a/drivers/iio/temperature/ltc2983.c b/drivers/iio/temperature/ltc2983.c
index 3c4524d57b8e..b4a8ca36458a 100644
--- a/drivers/iio/temperature/ltc2983.c
+++ b/drivers/iio/temperature/ltc2983.c
@@ -8,6 +8,8 @@
#include <linux/bitfield.h>
#include <linux/completion.h>
#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/iio/iio.h>
#include <linux/interrupt.h>
@@ -657,10 +659,11 @@ ltc2983_thermocouple_new(const struct fwnode_handle *child, struct ltc2983_data
const struct ltc2983_sensor *sensor)
{
struct ltc2983_thermocouple *thermo;
+ struct device *dev = &st->spi->dev;
u32 oc_current;
int ret;

- thermo = devm_kzalloc(&st->spi->dev, sizeof(*thermo), GFP_KERNEL);
+ thermo = devm_kzalloc(dev, sizeof(*thermo), GFP_KERNEL);
if (!thermo)
return ERR_PTR(-ENOMEM);

@@ -687,21 +690,19 @@ ltc2983_thermocouple_new(const struct fwnode_handle *child, struct ltc2983_data
LTC2983_THERMOCOUPLE_OC_CURR(3);
break;
default:
- dev_err(&st->spi->dev,
- "Invalid open circuit current:%u", oc_current);
- return ERR_PTR(-EINVAL);
+ return dev_errp_probe(dev, -EINVAL,
+ "Invalid open circuit current:%u",
+ oc_current);
}

thermo->sensor_config |= LTC2983_THERMOCOUPLE_OC_CHECK(1);
}
/* validate channel index */
if (!(thermo->sensor_config & LTC2983_THERMOCOUPLE_DIFF_MASK) &&
- sensor->chan < LTC2983_DIFFERENTIAL_CHAN_MIN) {
- dev_err(&st->spi->dev,
- "Invalid chann:%d for differential thermocouple",
- sensor->chan);
- return ERR_PTR(-EINVAL);
- }
+ sensor->chan < LTC2983_DIFFERENTIAL_CHAN_MIN)
+ return dev_errp_probe(dev, -EINVAL,
+ "Invalid chann:%d for differential thermocouple",
+ sensor->chan);

struct fwnode_handle *ref __free(fwnode_handle) =
fwnode_find_reference(child, "adi,cold-junction-handle", 0);
@@ -709,14 +710,13 @@ ltc2983_thermocouple_new(const struct fwnode_handle *child, struct ltc2983_data
ref = NULL;
} else {
ret = fwnode_property_read_u32(ref, "reg", &thermo->cold_junction_chan);
- if (ret) {
+ if (ret)
/*
* This would be catched later but we can just return
* the error right away.
*/
- dev_err(&st->spi->dev, "Property reg must be given\n");
- return ERR_PTR(ret);
- }
+ return dev_errp_probe(dev, ret,
+ "Property reg must be given\n");
}

/* check custom sensor */
@@ -752,16 +752,14 @@ ltc2983_rtd_new(const struct fwnode_handle *child, struct ltc2983_data *st,

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);
- }
+ if (IS_ERR(ref))
+ return dev_errp_probe(dev, PTR_ERR(ref),
+ "Property adi,rsense-handle missing or invalid");

ret = fwnode_property_read_u32(ref, "reg", &rtd->r_sense_chan);
- if (ret) {
- dev_err(dev, "Property reg must be given\n");
- return ERR_PTR(ret);
- }
+ if (ret)
+ return dev_errp_probe(dev, ret,
+ "Property reg must be given\n");

ret = fwnode_property_read_u32(child, "adi,number-of-wires", &n_wires);
if (!ret) {
@@ -780,19 +778,19 @@ ltc2983_rtd_new(const struct fwnode_handle *child, struct ltc2983_data *st,
rtd->sensor_config = LTC2983_RTD_N_WIRES(3);
break;
default:
- dev_err(dev, "Invalid number of wires:%u\n", n_wires);
- return ERR_PTR(-EINVAL);
+ return dev_errp_probe(dev, -EINVAL,
+ "Invalid number of wires:%u\n",
+ n_wires);
}
}

if (fwnode_property_read_bool(child, "adi,rsense-share")) {
/* Current rotation is only available with rsense sharing */
if (fwnode_property_read_bool(child, "adi,current-rotate")) {
- if (n_wires == 2 || n_wires == 3) {
- dev_err(dev,
- "Rotation not allowed for 2/3 Wire RTDs");
- return ERR_PTR(-EINVAL);
- }
+ if (n_wires == 2 || n_wires == 3)
+ return dev_errp_probe(dev, -EINVAL,
+ "Rotation not allowed for 2/3 Wire RTDs");
+
rtd->sensor_config |= LTC2983_RTD_C_ROTATE(1);
} else {
rtd->sensor_config |= LTC2983_RTD_R_SHARE(1);
@@ -815,29 +813,22 @@ ltc2983_rtd_new(const struct fwnode_handle *child, struct ltc2983_data *st,

if (((rtd->sensor_config & LTC2983_RTD_KELVIN_R_SENSE_MASK)
== LTC2983_RTD_KELVIN_R_SENSE_MASK) &&
- (rtd->r_sense_chan <= min)) {
+ (rtd->r_sense_chan <= min))
/* kelvin rsense*/
- dev_err(dev,
- "Invalid rsense chann:%d to use in kelvin rsense",
- rtd->r_sense_chan);
+ return dev_errp_probe(dev, -EINVAL,
+ "Invalid rsense chann:%d to use in kelvin rsense",
+ rtd->r_sense_chan);

- return ERR_PTR(-EINVAL);
- }
-
- if (sensor->chan < min || sensor->chan > max) {
- dev_err(dev, "Invalid chann:%d for the rtd config",
- sensor->chan);
-
- return ERR_PTR(-EINVAL);
- }
+ if (sensor->chan < min || sensor->chan > max)
+ return dev_errp_probe(dev, -EINVAL,
+ "Invalid chann:%d for the rtd config",
+ sensor->chan);
} else {
/* same as differential case */
- if (sensor->chan < LTC2983_DIFFERENTIAL_CHAN_MIN) {
- dev_err(&st->spi->dev,
- "Invalid chann:%d for RTD", sensor->chan);
-
- return ERR_PTR(-EINVAL);
- }
+ if (sensor->chan < LTC2983_DIFFERENTIAL_CHAN_MIN)
+ return dev_errp_probe(dev, -EINVAL,
+ "Invalid chann:%d for RTD",
+ sensor->chan);
}

/* check custom sensor */
@@ -885,10 +876,9 @@ ltc2983_rtd_new(const struct fwnode_handle *child, struct ltc2983_data *st,
rtd->excitation_current = 0x08;
break;
default:
- dev_err(&st->spi->dev,
- "Invalid value for excitation current(%u)",
- excitation_current);
- return ERR_PTR(-EINVAL);
+ return dev_errp_probe(dev, -EINVAL,
+ "Invalid value for excitation current(%u)",
+ excitation_current);
}
}

@@ -912,16 +902,14 @@ ltc2983_thermistor_new(const struct fwnode_handle *child, struct ltc2983_data *s

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);
- }
+ if (IS_ERR(ref))
+ return dev_errp_probe(dev, PTR_ERR(ref),
+ "Property adi,rsense-handle missing or invalid");

ret = fwnode_property_read_u32(ref, "reg", &thermistor->r_sense_chan);
- if (ret) {
- dev_err(dev, "rsense channel must be configured...\n");
- return ERR_PTR(ret);
- }
+ if (ret)
+ return dev_errp_probe(dev, ret,
+ "rsense channel must be configured...\n");

if (fwnode_property_read_bool(child, "adi,single-ended")) {
thermistor->sensor_config = LTC2983_THERMISTOR_SGL(1);
@@ -936,12 +924,10 @@ ltc2983_thermistor_new(const struct fwnode_handle *child, struct ltc2983_data *s
}
/* validate channel index */
if (!(thermistor->sensor_config & LTC2983_THERMISTOR_DIFF_MASK) &&
- sensor->chan < LTC2983_DIFFERENTIAL_CHAN_MIN) {
- dev_err(&st->spi->dev,
- "Invalid chann:%d for differential thermistor",
- sensor->chan);
- return ERR_PTR(-EINVAL);
- }
+ sensor->chan < LTC2983_DIFFERENTIAL_CHAN_MIN)
+ return dev_errp_probe(dev, -EINVAL,
+ "Invalid chann:%d for differential thermistor",
+ sensor->chan);

/* check custom sensor */
if (sensor->type >= LTC2983_SENSOR_THERMISTOR_STEINHART) {
@@ -980,12 +966,10 @@ ltc2983_thermistor_new(const struct fwnode_handle *child, struct ltc2983_data *s
switch (excitation_current) {
case 0:
/* auto range */
- if (sensor->type >=
- LTC2983_SENSOR_THERMISTOR_STEINHART) {
- dev_err(&st->spi->dev,
- "Auto Range not allowed for custom sensors\n");
- return ERR_PTR(-EINVAL);
- }
+ if (sensor->type >= LTC2983_SENSOR_THERMISTOR_STEINHART)
+ return dev_errp_probe(dev, -EINVAL,
+ "Auto Range not allowed for custom sensors\n");
+
thermistor->excitation_current = 0x0c;
break;
case 250:
@@ -1022,10 +1006,9 @@ ltc2983_thermistor_new(const struct fwnode_handle *child, struct ltc2983_data *s
thermistor->excitation_current = 0x0b;
break;
default:
- dev_err(&st->spi->dev,
- "Invalid value for excitation current(%u)",
- excitation_current);
- return ERR_PTR(-EINVAL);
+ return dev_errp_probe(dev, -EINVAL,
+ "Invalid value for excitation current(%u)",
+ excitation_current);
}
}

@@ -1036,11 +1019,12 @@ static struct ltc2983_sensor *
ltc2983_diode_new(const struct fwnode_handle *child, const struct ltc2983_data *st,
const struct ltc2983_sensor *sensor)
{
+ struct device *dev = &st->spi->dev;
struct ltc2983_diode *diode;
u32 temp = 0, excitation_current = 0;
int ret;

- diode = devm_kzalloc(&st->spi->dev, sizeof(*diode), GFP_KERNEL);
+ diode = devm_kzalloc(dev, sizeof(*diode), GFP_KERNEL);
if (!diode)
return ERR_PTR(-ENOMEM);

@@ -1055,12 +1039,11 @@ ltc2983_diode_new(const struct fwnode_handle *child, const struct ltc2983_data *

/* validate channel index */
if (!(diode->sensor_config & LTC2983_DIODE_DIFF_MASK) &&
- sensor->chan < LTC2983_DIFFERENTIAL_CHAN_MIN) {
- dev_err(&st->spi->dev,
- "Invalid chann:%d for differential thermistor",
- sensor->chan);
- return ERR_PTR(-EINVAL);
- }
+ sensor->chan < LTC2983_DIFFERENTIAL_CHAN_MIN)
+ return dev_errp_probe(dev, -EINVAL,
+ "Invalid chann:%d for differential thermistor",
+ sensor->chan);
+
/* set common parameters */
diode->sensor.fault_handler = ltc2983_common_fault_handler;
diode->sensor.assign_chan = ltc2983_diode_assign_chan;
@@ -1082,10 +1065,9 @@ ltc2983_diode_new(const struct fwnode_handle *child, const struct ltc2983_data *
diode->excitation_current = 0x03;
break;
default:
- dev_err(&st->spi->dev,
- "Invalid value for excitation current(%u)",
- excitation_current);
- return ERR_PTR(-EINVAL);
+ return dev_errp_probe(dev, -EINVAL,
+ "Invalid value for excitation current(%u)",
+ excitation_current);
}
}

@@ -1101,26 +1083,26 @@ static struct ltc2983_sensor *ltc2983_r_sense_new(struct fwnode_handle *child,
struct ltc2983_data *st,
const struct ltc2983_sensor *sensor)
{
+ struct device *dev = &st->spi->dev;
struct ltc2983_rsense *rsense;
int ret;
u32 temp;

- rsense = devm_kzalloc(&st->spi->dev, sizeof(*rsense), GFP_KERNEL);
+ rsense = devm_kzalloc(dev, sizeof(*rsense), GFP_KERNEL);
if (!rsense)
return ERR_PTR(-ENOMEM);

/* validate channel index */
- if (sensor->chan < LTC2983_DIFFERENTIAL_CHAN_MIN) {
- dev_err(&st->spi->dev, "Invalid chann:%d for r_sense",
- sensor->chan);
- return ERR_PTR(-EINVAL);
- }
+ if (sensor->chan < LTC2983_DIFFERENTIAL_CHAN_MIN)
+ return dev_errp_probe(dev, -EINVAL,
+ "Invalid chann:%d for r_sense",
+ sensor->chan);

ret = fwnode_property_read_u32(child, "adi,rsense-val-milli-ohms", &temp);
- if (ret) {
- dev_err(&st->spi->dev, "Property adi,rsense-val-milli-ohms missing\n");
- return ERR_PTR(-EINVAL);
- }
+ if (ret)
+ return dev_errp_probe(dev, -EINVAL,
+ "Property adi,rsense-val-milli-ohms missing\n");
+
/*
* Times 1000 because we have milli-ohms and __convert_to_raw
* expects scales of 1000000 which are used for all other
@@ -1139,21 +1121,21 @@ static struct ltc2983_sensor *ltc2983_adc_new(struct fwnode_handle *child,
struct ltc2983_data *st,
const struct ltc2983_sensor *sensor)
{
+ struct device *dev = &st->spi->dev;
struct ltc2983_adc *adc;

- adc = devm_kzalloc(&st->spi->dev, sizeof(*adc), GFP_KERNEL);
+ adc = devm_kzalloc(dev, sizeof(*adc), GFP_KERNEL);
if (!adc)
return ERR_PTR(-ENOMEM);

if (fwnode_property_read_bool(child, "adi,single-ended"))
adc->single_ended = true;

- if (!adc->single_ended &&
- sensor->chan < LTC2983_DIFFERENTIAL_CHAN_MIN) {
- dev_err(&st->spi->dev, "Invalid chan:%d for differential adc\n",
- sensor->chan);
- return ERR_PTR(-EINVAL);
- }
+ if (!adc->single_ended && sensor->chan < LTC2983_DIFFERENTIAL_CHAN_MIN)
+ return dev_errp_probe(dev, -EINVAL,
+ "Invalid chan:%d for differential adc\n",
+ sensor->chan);
+
/* set common parameters */
adc->sensor.assign_chan = ltc2983_adc_assign_chan;
adc->sensor.fault_handler = ltc2983_common_fault_handler;
@@ -1165,21 +1147,20 @@ static struct ltc2983_sensor *ltc2983_temp_new(struct fwnode_handle *child,
struct ltc2983_data *st,
const struct ltc2983_sensor *sensor)
{
+ struct device *dev = &st->spi->dev;
struct ltc2983_temp *temp;

- temp = devm_kzalloc(&st->spi->dev, sizeof(*temp), GFP_KERNEL);
+ temp = devm_kzalloc(dev, sizeof(*temp), GFP_KERNEL);
if (!temp)
return ERR_PTR(-ENOMEM);

if (fwnode_property_read_bool(child, "adi,single-ended"))
temp->single_ended = true;

- if (!temp->single_ended &&
- sensor->chan < LTC2983_DIFFERENTIAL_CHAN_MIN) {
- dev_err(&st->spi->dev, "Invalid chan:%d for differential temp\n",
- sensor->chan);
- return ERR_PTR(-EINVAL);
- }
+ if (!temp->single_ended && sensor->chan < LTC2983_DIFFERENTIAL_CHAN_MIN)
+ return dev_errp_probe(dev, -EINVAL,
+ "Invalid chan:%d for differential temp\n",
+ sensor->chan);

temp->custom = __ltc2983_custom_sensor_new(st, child, "adi,custom-temp",
false, 4096, true);
@@ -1329,10 +1310,9 @@ static int ltc2983_parse_fw(struct ltc2983_data *st)
device_property_read_u32(dev, "adi,filter-notch-freq", &st->filter_notch_freq);

st->num_channels = device_get_child_node_count(dev);
- if (!st->num_channels) {
- dev_err(&st->spi->dev, "At least one channel must be given!");
- return -EINVAL;
- }
+ if (!st->num_channels)
+ return dev_err_probe(dev, -EINVAL,
+ "At least one channel must be given!");

st->sensors = devm_kcalloc(dev, st->num_channels, sizeof(*st->sensors),
GFP_KERNEL);
@@ -1419,6 +1399,7 @@ static int ltc2983_eeprom_cmd(struct ltc2983_data *st, unsigned int cmd,
unsigned int wait_time, unsigned int status_reg,
unsigned long status_fail_mask)
{
+ struct device *dev = &st->spi->dev;
unsigned long time;
unsigned int val;
int ret;
@@ -1437,19 +1418,16 @@ static int ltc2983_eeprom_cmd(struct ltc2983_data *st, unsigned int cmd,

time = wait_for_completion_timeout(&st->completion,
msecs_to_jiffies(wait_time));
- if (!time) {
- dev_err(&st->spi->dev, "EEPROM command timed out\n");
- return -ETIMEDOUT;
- }
+ if (!time)
+ return dev_err_probe(dev, -ETIMEDOUT, "EEPROM command timed out\n");

ret = regmap_read(st->regmap, status_reg, &val);
if (ret)
return ret;

- if (val & status_fail_mask) {
- dev_err(&st->spi->dev, "EEPROM command failed: 0x%02X\n", val);
- return -EINVAL;
- }
+ if (val & status_fail_mask)
+ return dev_err_probe(dev, -EINVAL,
+ "EEPROM command failed: 0x%02X\n", val);

return 0;
}
@@ -1457,16 +1435,15 @@ static int ltc2983_eeprom_cmd(struct ltc2983_data *st, unsigned int cmd,
static int ltc2983_setup(struct ltc2983_data *st, bool assign_iio)
{
u32 iio_chan_t = 0, iio_chan_v = 0, chan, iio_idx = 0, status;
+ struct device *dev = &st->spi->dev;
int ret;

/* make sure the device is up: start bit (7) is 0 and done bit (6) is 1 */
ret = regmap_read_poll_timeout(st->regmap, LTC2983_STATUS_REG, status,
LTC2983_STATUS_UP(status) == 1, 25000,
25000 * 10);
- if (ret) {
- dev_err(&st->spi->dev, "Device startup timed out\n");
- return ret;
- }
+ if (ret)
+ return dev_err_probe(dev, ret, "Device startup timed out\n");

ret = regmap_update_bits(st->regmap, LTC2983_GLOBAL_CONFIG_REG,
LTC2983_NOTCH_FREQ_MASK,
@@ -1566,12 +1543,13 @@ static const struct iio_info ltc2983_iio_info = {

static int ltc2983_probe(struct spi_device *spi)
{
+ struct device *dev = &spi->dev;
struct ltc2983_data *st;
struct iio_dev *indio_dev;
struct gpio_desc *gpio;
int ret;

- indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
+ indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
if (!indio_dev)
return -ENOMEM;

@@ -1582,10 +1560,9 @@ static int ltc2983_probe(struct spi_device *spi)
return -ENODEV;

st->regmap = devm_regmap_init_spi(spi, &ltc2983_regmap_config);
- if (IS_ERR(st->regmap)) {
- dev_err(&spi->dev, "Failed to initialize regmap\n");
- return PTR_ERR(st->regmap);
- }
+ if (IS_ERR(st->regmap))
+ return dev_err_probe(dev, PTR_ERR(st->regmap),
+ "Failed to initialize regmap\n");

mutex_init(&st->lock);
init_completion(&st->completion);
@@ -1597,7 +1574,7 @@ static int ltc2983_probe(struct spi_device *spi)
if (ret)
return ret;

- gpio = devm_gpiod_get_optional(&st->spi->dev, "reset", GPIOD_OUT_HIGH);
+ gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
if (IS_ERR(gpio))
return PTR_ERR(gpio);

@@ -1607,7 +1584,7 @@ static int ltc2983_probe(struct spi_device *spi)
gpiod_set_value_cansleep(gpio, 0);
}

- st->iio_chan = devm_kzalloc(&spi->dev,
+ st->iio_chan = devm_kzalloc(dev,
st->iio_channels * sizeof(*st->iio_chan),
GFP_KERNEL);
if (!st->iio_chan)
@@ -1617,12 +1594,10 @@ static int ltc2983_probe(struct spi_device *spi)
if (ret)
return ret;

- ret = devm_request_irq(&spi->dev, spi->irq, ltc2983_irq_handler,
+ ret = devm_request_irq(dev, spi->irq, ltc2983_irq_handler,
IRQF_TRIGGER_RISING, st->info->name, st);
- if (ret) {
- dev_err(&spi->dev, "failed to request an irq, %d", ret);
- return ret;
- }
+ if (ret)
+ return dev_err_probe(dev, ret, "failed to request an irq\n");

if (st->info->has_eeprom) {
ret = ltc2983_eeprom_cmd(st, LTC2983_EEPROM_WRITE_CMD,
@@ -1639,7 +1614,7 @@ static int ltc2983_probe(struct spi_device *spi)
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->info = &ltc2983_iio_info;

- return devm_iio_device_register(&spi->dev, indio_dev);
+ return devm_iio_device_register(dev, indio_dev);
}

static int ltc2983_resume(struct device *dev)

--
2.44.0