[PATCH v3 3/3] staging: iio: ad9832: Add minor improvements to ad9832_write_powerdown

[Gabriel Shahrouzi <gshahrouzi@gmail.com>]

Minimize size of type that needs to be used by replacing unsigned long
with bool. Avoid redundancy by checking if cached power state is the
same as the one requested.

Signed-off-by: Gabriel Shahrouzi <gshahrouzi@gmail.com>
---
 drivers/staging/iio/frequency/ad9832.c | 18 ++++++++++++------
 1 file changed, 12 insertions(+), 6 deletions(-)

diff --git a/drivers/staging/iio/frequency/ad9832.c b/drivers/staging/iio/frequency/ad9832.c
index a8fc20379efed..2ab6026d56b5c 100644
--- a/drivers/staging/iio/frequency/ad9832.c
+++ b/drivers/staging/iio/frequency/ad9832.c
@@ -173,13 +173,19 @@ static ssize_t ad9832_write_powerdown(struct device *dev, struct device_attribut
 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 	struct ad9832_state *st = iio_priv(indio_dev);
 	int ret;
-	unsigned long val;
+	bool val;
+	bool cur;
 
-	ret = kstrtoul(buf, 10, &val);
+	ret = kstrtobool(buf, &val);
 	if (ret)
-		goto error_ret;
+		return ret;
 
 	mutex_lock(&st->lock);
+
+	cur = !!(st->ctrl_src & AD9832_SLEEP);
+	if (val == cur)
+		goto unlock;
+
 	if (val)
 		st->ctrl_src |= AD9832_SLEEP;
 	else
@@ -189,10 +195,10 @@ static ssize_t ad9832_write_powerdown(struct device *dev, struct device_attribut
 	st->data = cpu_to_be16((AD9832_CMD_SLEEPRESCLR << CMD_SHIFT) |
 				st->ctrl_src);
 	ret = spi_sync(st->spi, &st->msg);
-	mutex_unlock(&st->lock);
 
-error_ret:
-	return ret ? ret : len;
+unlock:
+	mutex_unlock(&st->lock);
+	return len;
 }
 
 static ssize_t ad9832_write(struct device *dev, struct device_attribute *attr,
-- 
2.43.0