[PATCH v2 08/10] iio: light: opt3001: move driver to guard(mutex)() use

[Joshua Crofts <joshua.crofts1@gmail.com>]

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@intel.com>
Signed-off-by: Joshua Crofts <joshua.crofts1@gmail.com>
---
 drivers/iio/light/opt3001.c | 61 +++++++++++++--------------------------------
 1 file changed, 18 insertions(+), 43 deletions(-)

diff --git a/drivers/iio/light/opt3001.c b/drivers/iio/light/opt3001.c
index 6f7c524d3a7a41c5177c9b02ebe1b7858294a0b4..39ea60c0af2c1ec7473d49b73778cac1f9bb6086 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>
@@ -478,7 +479,6 @@ 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;
@@ -486,23 +486,17 @@ 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,
@@ -510,7 +504,6 @@ 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;
@@ -524,11 +517,9 @@ 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,
@@ -539,28 +530,23 @@ 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,
@@ -587,12 +573,12 @@ 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;
@@ -615,18 +601,12 @@ 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) {
+	if (ret < 0)
 		dev_err(dev, "failed to write register %02x\n", reg);
-		goto err;
-	}
-
-err:
-	mutex_unlock(&opt->lock);
 
 	return ret;
 }
@@ -660,7 +640,7 @@ 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;
@@ -669,21 +649,16 @@ 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;
 	opt3001_set_mode(opt, &reg, mode);
 
 	ret = i2c_smbus_write_word_swapped(client, OPT3001_CONFIGURATION, reg);
-	if (ret < 0) {
+	if (ret < 0)
 		dev_err(dev, "failed to write register %02x\n",
 			OPT3001_CONFIGURATION);
-		goto err;
-	}
-
-err:
-	mutex_unlock(&opt->lock);
 
 	return ret;
 }

-- 
2.47.3