On 1/19/21 3:22 AM, Guoqing Chi wrote:
> From: chiguoqing <chi962464zy@xxxxxxx>
>
> Adding mutex_lock, when read and write reg need to use this lock to
> avoid race.
>
> Signed-off-by: Guoqing Chi <chiguoqing@xxxxxxxxxx>
> ---
> v2:Follow write function to fix read function.
> Adding mutex init in core probe function.
> Adding break in switch case at read and write function.
>
> drivers/iio/imu/bmi160/bmi160.h | 2 ++
> drivers/iio/imu/bmi160/bmi160_core.c | 34 +++++++++++++++++++---------
> 2 files changed, 25 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/iio/imu/bmi160/bmi160.h b/drivers/iio/imu/bmi160/bmi160.h
> index 32c2ea2d7112..0c189a8b5b53 100644
> --- a/drivers/iio/imu/bmi160/bmi160.h
> +++ b/drivers/iio/imu/bmi160/bmi160.h
> @@ -3,9 +3,11 @@
> #define BMI160_H_
>
> #include <linux/iio/iio.h>
> +#include <linux/mutex.h>
> #include <linux/regulator/consumer.h>
>
> struct bmi160_data {
> + struct mutex lock;
> struct regmap *regmap;
> struct iio_trigger *trig;
> struct regulator_bulk_data supplies[2];
> diff --git a/drivers/iio/imu/bmi160/bmi160_core.c b/drivers/iio/imu/bmi160/bmi160_core.c
> index 290b5ef83f77..e303378f4841 100644
> --- a/drivers/iio/imu/bmi160/bmi160_core.c
> +++ b/drivers/iio/imu/bmi160/bmi160_core.c
> @@ -452,26 +452,32 @@ static int bmi160_read_raw(struct iio_dev *indio_dev,
> int ret;
> struct bmi160_data *data = iio_priv(indio_dev);
>
> + mutex_lock(&data->lock);
> switch (mask) {
> case IIO_CHAN_INFO_RAW:
> ret = bmi160_get_data(data, chan->type, chan->channel2, val);
> - if (ret)
> - return ret;
> - return IIO_VAL_INT;
> + if (!ret)
> + ret = IIO_VAL_INT;
> + break;
> case IIO_CHAN_INFO_SCALE:
> *val = 0;
> ret = bmi160_get_scale(data,
> bmi160_to_sensor(chan->type), val2);
> - return ret ? ret : IIO_VAL_INT_PLUS_MICRO;
> + if (!ret)
> + ret = IIO_VAL_INT_PLUS_MICRO;
Looking better, another question..
Why does the write() function return the results directly while the read() function
translates them to other values ?
Tom
> + break;
> case IIO_CHAN_INFO_SAMP_FREQ:
> ret = bmi160_get_odr(data, bmi160_to_sensor(chan->type),
> val, val2);
> - return ret ? ret : IIO_VAL_INT_PLUS_MICRO;
> + if (!ret)
> + ret = IIO_VAL_INT_PLUS_MICRO;
> + break;
> default:
> - return -EINVAL;
> + ret = -EINVAL;
> }
> + mutex_unlock(&data->lock);
>
> - return 0;
> + return ret;
> }
>
> static int bmi160_write_raw(struct iio_dev *indio_dev,
> @@ -479,19 +485,24 @@ static int bmi160_write_raw(struct iio_dev *indio_dev,
> int val, int val2, long mask)
> {
> struct bmi160_data *data = iio_priv(indio_dev);
> + int result;
>
> + mutex_lock(&data->lock);
> switch (mask) {
> case IIO_CHAN_INFO_SCALE:
> - return bmi160_set_scale(data,
> + result = bmi160_set_scale(data,
> bmi160_to_sensor(chan->type), val2);
> + break;
> case IIO_CHAN_INFO_SAMP_FREQ:
> - return bmi160_set_odr(data, bmi160_to_sensor(chan->type),
> + result = bmi160_set_odr(data, bmi160_to_sensor(chan->type),
> val, val2);
> + break;
> default:
> - return -EINVAL;
> + result = -EINVAL;
> }
> + mutex_unlock(&data->lock);
>
> - return 0;
> + return result;
> }
>
> static
> @@ -838,6 +849,7 @@ int bmi160_core_probe(struct device *dev, struct regmap *regmap,
> return -ENOMEM;
>
> data = iio_priv(indio_dev);
> + mutex_init(&data->lock);
> dev_set_drvdata(dev, indio_dev);
> data->regmap = regmap;
>
