[PATCH v1 2/3] gpiolib: sysfs: Move kstrtox() calls outside of the mutex lock

From: Andy Shevchenko
Date: Wed Feb 09 2022 - 07:05:17 EST


In a few places we perform kstrtox() operations under mutex that
do not require any locking. Move them outside of the mutex locks.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
---
drivers/gpio/gpiolib-sysfs.c | 28 ++++++++++++----------------
1 file changed, 12 insertions(+), 16 deletions(-)

diff --git a/drivers/gpio/gpiolib-sysfs.c b/drivers/gpio/gpiolib-sysfs.c
index 57d8ecab53b7..e7828d4dc7a8 100644
--- a/drivers/gpio/gpiolib-sysfs.c
+++ b/drivers/gpio/gpiolib-sysfs.c
@@ -121,24 +121,18 @@ static ssize_t value_store(struct device *dev,
{
struct gpiod_data *data = dev_get_drvdata(dev);
struct gpio_desc *desc = data->desc;
- ssize_t status = 0;
+ ssize_t status;
+ long value;
+
+ status = kstrtol(buf, 0, &value);

mutex_lock(&data->mutex);

if (!test_bit(FLAG_IS_OUT, &desc->flags)) {
status = -EPERM;
- } else {
- long value;
-
- if (size <= 2 && isdigit(buf[0]) &&
- (size == 1 || buf[1] == '\n'))
- value = buf[0] - '0';
- else
- status = kstrtol(buf, 0, &value);
- if (status == 0) {
- gpiod_set_value_cansleep(desc, value);
- status = size;
- }
+ } else if (status == 0) {
+ gpiod_set_value_cansleep(desc, value);
+ status = size;
}

mutex_unlock(&data->mutex);
@@ -342,11 +336,13 @@ static ssize_t active_low_store(struct device *dev,
ssize_t status;
long value;

+ status = kstrtol(buf, 0, &value);
+ if (status)
+ return status;
+
mutex_lock(&data->mutex);

- status = kstrtol(buf, 0, &value);
- if (status == 0)
- status = gpio_sysfs_set_active_low(dev, value);
+ status = gpio_sysfs_set_active_low(dev, value);

mutex_unlock(&data->mutex);

--
2.34.1