diff options
Diffstat (limited to 'drivers/iio/adc/exynos_adc.c')
| -rw-r--r-- | drivers/iio/adc/exynos_adc.c | 30 |
1 files changed, 19 insertions, 11 deletions
diff --git a/drivers/iio/adc/exynos_adc.c b/drivers/iio/adc/exynos_adc.c index 7d23b6c33284..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; } @@ -844,13 +854,9 @@ static int exynos_adc_probe(struct platform_device *pdev) } info->vdd = devm_regulator_get(&pdev->dev, "vdd"); - if (IS_ERR(info->vdd)) { - if (PTR_ERR(info->vdd) != -EPROBE_DEFER) - dev_err(&pdev->dev, - "failed getting regulator, err = %ld\n", - PTR_ERR(info->vdd)); - return PTR_ERR(info->vdd); - } + if (IS_ERR(info->vdd)) + return dev_err_probe(&pdev->dev, PTR_ERR(info->vdd), + "failed getting regulator"); ret = regulator_enable(info->vdd); if (ret) @@ -872,6 +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) { |