[PATCH v3 6/7] iio: light: opt3001: move driver to guard(mutex)() use
From: Joshua Crofts via B4 Relay
Date: Thu May 21 2026 - 06:13:59 EST
From: Joshua Crofts <joshua.crofts1@xxxxxxxxx>
Move driver to use guard(mutex)() macro, to facilitate automatic
locking/unlocking of resources. This modernizes the driver and
improves code style.
While at it, remove unnecessary gotos and return variables.
Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxx>
Signed-off-by: Joshua Crofts <joshua.crofts1@xxxxxxxxx>
---
drivers/iio/light/opt3001.c | 140 +++++++++++++++++++-------------------------
1 file changed, 60 insertions(+), 80 deletions(-)
diff --git a/drivers/iio/light/opt3001.c b/drivers/iio/light/opt3001.c
index d5262488dac889066a53d3234762e0557f9e3cbc..ac1c7ba5679867f6b814894680e317615f2e373b 100644
--- a/drivers/iio/light/opt3001.c
+++ b/drivers/iio/light/opt3001.c
@@ -10,6 +10,7 @@
#include <linux/array_size.h>
#include <linux/bits.h>
+#include <linux/cleanup.h>
#include <linux/delay.h>
#include <linux/dev_printk.h>
#include <linux/errno.h>
@@ -477,7 +478,6 @@ static int opt3001_read_raw(struct iio_dev *iio,
int *val, int *val2, long mask)
{
struct opt3001 *opt = iio_priv(iio);
- int ret;
if (opt->mode == OPT3001_CONFIGURATION_M_CONTINUOUS)
return -EBUSY;
@@ -485,23 +485,17 @@ static int opt3001_read_raw(struct iio_dev *iio,
if (chan->type != opt->chip_info->chan_type)
return -EINVAL;
- mutex_lock(&opt->lock);
+ guard(mutex)(&opt->lock);
switch (mask) {
case IIO_CHAN_INFO_RAW:
case IIO_CHAN_INFO_PROCESSED:
- ret = opt3001_get_processed(opt, val, val2);
- break;
+ return opt3001_get_processed(opt, val, val2);
case IIO_CHAN_INFO_INT_TIME:
- ret = opt3001_get_int_time(opt, val, val2);
- break;
+ return opt3001_get_int_time(opt, val, val2);
default:
- ret = -EINVAL;
+ return -EINVAL;
}
-
- mutex_unlock(&opt->lock);
-
- return ret;
}
static int opt3001_write_raw(struct iio_dev *iio,
@@ -509,7 +503,6 @@ static int opt3001_write_raw(struct iio_dev *iio,
int val, int val2, long mask)
{
struct opt3001 *opt = iio_priv(iio);
- int ret;
if (opt->mode == OPT3001_CONFIGURATION_M_CONTINUOUS)
return -EBUSY;
@@ -523,11 +516,9 @@ static int opt3001_write_raw(struct iio_dev *iio,
if (val != 0)
return -EINVAL;
- mutex_lock(&opt->lock);
- ret = opt3001_set_int_time(opt, val2);
- mutex_unlock(&opt->lock);
+ guard(mutex)(&opt->lock);
- return ret;
+ return opt3001_set_int_time(opt, val2);
}
static int opt3001_read_event_value(struct iio_dev *iio,
@@ -538,28 +529,23 @@ static int opt3001_read_event_value(struct iio_dev *iio,
int *val, int *val2)
{
struct opt3001 *opt = iio_priv(iio);
- int ret = IIO_VAL_INT_PLUS_MICRO;
- mutex_lock(&opt->lock);
+ guard(mutex)(&opt->lock);
switch (dir) {
case IIO_EV_DIR_RISING:
opt3001_to_iio_ret(opt, opt->high_thresh_exp,
opt->high_thresh_mantissa,
val, val2);
- break;
+ return IIO_VAL_INT_PLUS_MICRO;
case IIO_EV_DIR_FALLING:
opt3001_to_iio_ret(opt, opt->low_thresh_exp,
opt->low_thresh_mantissa,
val, val2);
- break;
+ return IIO_VAL_INT_PLUS_MICRO;
default:
- ret = -EINVAL;
+ return -EINVAL;
}
-
- mutex_unlock(&opt->lock);
-
- return ret;
}
static int opt3001_write_event_value(struct iio_dev *iio,
@@ -586,12 +572,12 @@ static int opt3001_write_event_value(struct iio_dev *iio,
if (val < 0)
return -EINVAL;
- mutex_lock(&opt->lock);
+ guard(mutex)(&opt->lock);
ret = opt3001_find_scale(opt, val, val2, &exponent);
if (ret < 0) {
dev_err(dev, "can't find scale for %d.%06u\n", val, val2);
- goto err;
+ return ret;
}
whole = opt->chip_info->factor_whole;
@@ -614,20 +600,16 @@ static int opt3001_write_event_value(struct iio_dev *iio,
opt->low_thresh_exp = exponent;
break;
default:
- ret = -EINVAL;
- goto err;
+ return -EINVAL;
}
ret = i2c_smbus_write_word_swapped(client, reg, value);
if (ret < 0) {
dev_err(dev, "failed to write register %02x\n", reg);
- goto err;
+ return ret;
}
-err:
- mutex_unlock(&opt->lock);
-
- return ret;
+ return 0;
}
static int opt3001_read_event_config(struct iio_dev *iio,
@@ -659,7 +641,7 @@ static int opt3001_write_event_config(struct iio_dev *iio,
if (!state && opt->mode == OPT3001_CONFIGURATION_M_SHUTDOWN)
return 0;
- mutex_lock(&opt->lock);
+ guard(mutex)(&opt->lock);
mode = state ? OPT3001_CONFIGURATION_M_CONTINUOUS
: OPT3001_CONFIGURATION_M_SHUTDOWN;
@@ -668,7 +650,7 @@ static int opt3001_write_event_config(struct iio_dev *iio,
if (ret < 0) {
dev_err(dev, "failed to read register %02x\n",
OPT3001_CONFIGURATION);
- goto err;
+ return ret;
}
reg = ret;
@@ -678,13 +660,10 @@ static int opt3001_write_event_config(struct iio_dev *iio,
if (ret < 0) {
dev_err(dev, "failed to write register %02x\n",
OPT3001_CONFIGURATION);
- goto err;
+ return ret;
}
-err:
- mutex_unlock(&opt->lock);
-
- return ret;
+ return 0;
}
static const struct iio_info opt3001_info = {
@@ -726,6 +705,31 @@ static int opt3001_read_id(struct opt3001 *opt)
return 0;
}
+static void opt3001_power_off(void *data)
+{
+ struct opt3001 *opt = data;
+ struct i2c_client *client = opt->client;
+ struct device *dev = opt->dev;
+ u16 reg_val;
+ int ret;
+
+ ret = i2c_smbus_read_word_swapped(client, OPT3001_CONFIGURATION);
+ if (ret < 0) {
+ dev_err(dev, "failed to read register %02x\n",
+ OPT3001_CONFIGURATION);
+ return;
+ }
+
+ reg_val = ret;
+ opt3001_set_mode(opt, ®_val, OPT3001_CONFIGURATION_M_SHUTDOWN);
+
+ ret = i2c_smbus_write_word_swapped(client, OPT3001_CONFIGURATION,
+ reg_val);
+ if (ret < 0)
+ dev_err(dev, "failed to write to register %02x\n",
+ OPT3001_CONFIGURATION);
+}
+
static int opt3001_configure(struct opt3001 *opt)
{
struct i2c_client *client = opt->client;
@@ -764,6 +768,11 @@ static int opt3001_configure(struct opt3001 *opt)
return dev_err_probe(dev, ret, "failed to write register %02x\n",
OPT3001_CONFIGURATION);
+ ret = devm_add_action_or_reset(dev, opt3001_power_off, opt);
+ if (ret)
+ return dev_err_probe(dev, ret,
+ "failed to register power off function\n");
+
ret = i2c_smbus_read_word_swapped(client, OPT3001_LOW_LIMIT);
if (ret < 0)
return dev_err_probe(dev, ret, "failed to read register %02x\n",
@@ -857,7 +866,10 @@ static int opt3001_probe(struct i2c_client *client)
opt->client = client;
opt->chip_info = i2c_get_match_data(client);
- mutex_init(&opt->lock);
+ ret = devm_mutex_init(dev, &opt->lock);
+ if (ret)
+ return ret;
+
init_waitqueue_head(&opt->result_ready_queue);
i2c_set_clientdata(client, iio);
@@ -879,49 +891,18 @@ static int opt3001_probe(struct i2c_client *client)
/* Make use of INT pin only if valid IRQ no. is given */
if (irq > 0) {
- ret = request_threaded_irq(irq, NULL, opt3001_irq,
- IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
- "opt3001", iio);
+ ret = devm_request_threaded_irq(dev, irq, NULL, opt3001_irq,
+ IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+ "opt3001", iio);
if (ret)
- return dev_err_probe(dev, ret,
- "failed to request IRQ #%d\n",
- irq);
+ return ret;
+
opt->use_irq = true;
} else {
dev_dbg(dev, "enabling interrupt-less operation\n");
}
- return iio_device_register(iio);
-}
-
-static void opt3001_remove(struct i2c_client *client)
-{
- struct iio_dev *iio = i2c_get_clientdata(client);
- struct opt3001 *opt = iio_priv(iio);
- struct device *dev = &client->dev;
- int ret;
- u16 reg;
-
- iio_device_unregister(iio);
-
- if (opt->use_irq)
- free_irq(client->irq, iio);
-
- ret = i2c_smbus_read_word_swapped(client, OPT3001_CONFIGURATION);
- if (ret < 0) {
- dev_err(dev, "failed to read register %02x\n",
- OPT3001_CONFIGURATION);
- return;
- }
-
- reg = ret;
- opt3001_set_mode(opt, ®, OPT3001_CONFIGURATION_M_SHUTDOWN);
-
- ret = i2c_smbus_write_word_swapped(client, OPT3001_CONFIGURATION, reg);
- if (ret < 0) {
- dev_err(dev, "failed to write register %02x\n",
- OPT3001_CONFIGURATION);
- }
+ return devm_iio_device_register(dev, iio);
}
static const struct opt3001_chip_info opt3001_chip_information = {
@@ -962,7 +943,6 @@ MODULE_DEVICE_TABLE(of, opt3001_of_match);
static struct i2c_driver opt3001_driver = {
.probe = opt3001_probe,
- .remove = opt3001_remove,
.id_table = opt3001_id,
.driver = {
--
2.47.3