On Wed, 26 Aug 2020 16:22:03 +0300
Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx> wrote:
> From: Sergiu Cuciurean <sergiu.cuciurean@xxxxxxxxxx>
>
> As part of the general cleanup of indio_dev->mlock, this change replaces
> it with a local lock, to protect potential concurrent access to the
> completion callback during a conversion.
>
> Signed-off-by: Sergiu Cuciurean <sergiu.cuciurean@xxxxxxxxxx>
> Signed-off-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>
Same comment as the other one about needing lock scope to be documented.
Otherwise looks good. I thought we only had complicated uses of this
left, but clearly not :)
Jonathan
> ---
> drivers/iio/adc/exynos_adc.c | 12 ++++++++----
> 1 file changed, 8 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/iio/adc/exynos_adc.c b/drivers/iio/adc/exynos_adc.c
> index 7d23b6c33284..6a49f8dfab22 100644
> --- a/drivers/iio/adc/exynos_adc.c
> +++ b/drivers/iio/adc/exynos_adc.c
> @@ -132,6 +132,8 @@ struct exynos_adc {
>
> struct completion completion;
>
> + struct mutex lock;
> +
> u32 value;
> unsigned int version;
>
> @@ -542,7 +544,7 @@ static int exynos_read_raw(struct iio_dev *indio_dev,
> return -EINVAL;
> }
>
> - mutex_lock(&indio_dev->mlock);
> + mutex_lock(&info->lock);
> reinit_completion(&info->completion);
>
> /* Select the channel to be used and Trigger conversion */
> @@ -562,7 +564,7 @@ static int exynos_read_raw(struct iio_dev *indio_dev,
> ret = IIO_VAL_INT;
> }
>
> - mutex_unlock(&indio_dev->mlock);
> + mutex_unlock(&info->lock);
>
> return ret;
> }
> @@ -573,7 +575,7 @@ static int exynos_read_s3c64xx_ts(struct iio_dev *indio_dev, int *x, int *y)
> unsigned long timeout;
> int ret;
>
> - mutex_lock(&indio_dev->mlock);
> + mutex_lock(&info->lock);
> info->read_ts = true;
>
> reinit_completion(&info->completion);
> @@ -598,7 +600,7 @@ static int exynos_read_s3c64xx_ts(struct iio_dev *indio_dev, int *x, int *y)
> }
>
> info->read_ts = false;
> - mutex_unlock(&indio_dev->mlock);
> + mutex_unlock(&info->lock);
>
> return ret;
> }
> @@ -872,6 +874,8 @@ static int exynos_adc_probe(struct platform_device *pdev)
> indio_dev->channels = exynos_adc_iio_channels;
> indio_dev->num_channels = info->data->num_channels;
>
> + mutex_init(&info->lock);
> +
> ret = request_irq(info->irq, exynos_adc_isr,
> 0, dev_name(&pdev->dev), info);
> if (ret < 0) {
