diff options
| author | Sergiu Cuciurean <sergiu.cuciurean@analog.com> | 2020-09-16 12:31:23 +0300 |
|---|---|---|
| committer | Jonathan Cameron <Jonathan.Cameron@huawei.com> | 2020-09-21 22:01:50 +0300 |
| commit | d390ff735d0a61e4703bf124866ef6d4be7fdc64 (patch) | |
| tree | 82a5068ef76bcb44c40e19c80529fa4439bb8a5c /drivers/iio | |
| parent | 7f6fc073fd8571a0a37df332cf40b805ff6f4756 (diff) | |
| download | linux-d390ff735d0a61e4703bf124866ef6d4be7fdc64.tar.xz | |
iio: adc: exynos_adc: Replace indio_dev->mlock with own device lock
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.
This is part of a bigger cleanup.
Link: https://lore.kernel.org/linux-iio/CA+U=Dsoo6YABe5ODLp+eFNPGFDjk5ZeQEceGkqjxXcVEhLWubw@mail.gmail.com/
Signed-off-by: Sergiu Cuciurean <sergiu.cuciurean@analog.com>
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20200916093123.78954-1-alexandru.ardelean@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Diffstat (limited to 'drivers/iio')
| -rw-r--r-- | drivers/iio/adc/exynos_adc.c | 20 |
1 files changed, 16 insertions, 4 deletions
diff --git a/drivers/iio/adc/exynos_adc.c b/drivers/iio/adc/exynos_adc.c index 20477b249f2a..99f4404e9fd1 100644 --- a/drivers/iio/adc/exynos_adc.c +++ b/drivers/iio/adc/exynos_adc.c @@ -138,6 +138,16 @@ struct exynos_adc { bool read_ts; u32 ts_x; u32 ts_y; + + /* + * Lock to protect from potential concurrent access to the + * completion callback during a manual conversion. For this driver + * a wait-callback is used to wait for the conversion result, + * so in the meantime no other read request (or conversion start) + * must be performed, otherwise it would interfere with the + * current conversion result. + */ + struct mutex lock; }; struct exynos_adc_data { @@ -542,7 +552,7 @@ 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 +572,7 @@ 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 +583,7 @@ 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 +608,7 @@ 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; } @@ -868,6 +878,8 @@ 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) { |