staging: iio: tsl2583: add locking to sysfs attributes

in_illuminance_input_target_show(), in_illuminance_input_target_store(),
in_illuminance_calibrate_store(), and in_illuminance_lux_table_store()
accesses data from the tsl2583_chip struct. Some of these fields can be
modified by other parts of the driver concurrently. This patch adds the
mutex locking to these sysfs attributes.

Signed-off-by: Brian Masney <masneyb@onstation.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

diff --git a/drivers/staging/iio/light/tsl2583.c b/drivers/staging/iio/light/tsl2583.c
index 98afa5b..49b19f5 100644 (file)
--- a/drivers/staging/iio/light/tsl2583.c
+++ b/drivers/staging/iio/light/tsl2583.c
@@ -513,8 +513,13 @@ static ssize_t in_illuminance_input_target_show(struct device *dev,
 {
        struct iio_dev *indio_dev = dev_to_iio_dev(dev);
        struct tsl2583_chip *chip = iio_priv(indio_dev);
+       int ret;
+
+       mutex_lock(&chip->als_mutex);
+       ret = sprintf(buf, "%d\n", chip->taos_settings.als_cal_target);
+       mutex_unlock(&chip->als_mutex);
 
-       return sprintf(buf, "%d\n", chip->taos_settings.als_cal_target);
+       return ret;
 }
 
 static ssize_t in_illuminance_input_target_store(struct device *dev,
@@ -528,7 +533,9 @@ static ssize_t in_illuminance_input_target_store(struct device *dev,
        if (kstrtoint(buf, 0, &value) || !value)
                return -EINVAL;
 
+       mutex_lock(&chip->als_mutex);
        chip->taos_settings.als_cal_target = value;
+       mutex_unlock(&chip->als_mutex);
 
        return len;
 }
@@ -538,12 +545,15 @@ static ssize_t in_illuminance_calibrate_store(struct device *dev,
                                              const char *buf, size_t len)
 {
        struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+       struct tsl2583_chip *chip = iio_priv(indio_dev);
        int value;
 
        if (kstrtoint(buf, 0, &value) || value != 1)
                return -EINVAL;
 
+       mutex_lock(&chip->als_mutex);
        taos_als_calibrate(indio_dev);
+       mutex_unlock(&chip->als_mutex);
 
        return len;
 }
@@ -583,6 +593,8 @@ static ssize_t in_illuminance_lux_table_store(struct device *dev,
        int value[ARRAY_SIZE(taos_device_lux) * 3 + 1];
        int n, ret = -EINVAL;
 
+       mutex_lock(&chip->als_mutex);
+
        get_options(buf, ARRAY_SIZE(value), value);
 
        /* We now have an array of ints starting at value[1], and
@@ -617,6 +629,8 @@ static ssize_t in_illuminance_lux_table_store(struct device *dev,
        ret = len;
 
 done:
+       mutex_unlock(&chip->als_mutex);
+
        return ret;
 }