[PATCH 5.4 218/434] iio: dln2-adc: fix iio_triggered_buffer_postenable() position

From: Greg Kroah-Hartman
Date: Sun Dec 29 2019 - 12:51:37 EST


From: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>

[ Upstream commit a7bddfe2dfce1d8859422124abe1964e0ecd386e ]

The iio_triggered_buffer_postenable() hook should be called first to
attach the poll function. The iio_triggered_buffer_predisable() hook is
called last (as is it should).

This change moves iio_triggered_buffer_postenable() to be called first. It
adds iio_triggered_buffer_predisable() on the error paths of the postenable
hook.
For the predisable hook, some code-paths have been changed to make sure
that the iio_triggered_buffer_predisable() hook gets called in case there
is an error before it.

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/iio/adc/dln2-adc.c | 20 ++++++++++++++------
1 file changed, 14 insertions(+), 6 deletions(-)

diff --git a/drivers/iio/adc/dln2-adc.c b/drivers/iio/adc/dln2-adc.c
index 5fa78c273a25..65c7c9329b1c 100644
--- a/drivers/iio/adc/dln2-adc.c
+++ b/drivers/iio/adc/dln2-adc.c
@@ -524,6 +524,10 @@ static int dln2_adc_triggered_buffer_postenable(struct iio_dev *indio_dev)
u16 conflict;
unsigned int trigger_chan;

+ ret = iio_triggered_buffer_postenable(indio_dev);
+ if (ret)
+ return ret;
+
mutex_lock(&dln2->mutex);

/* Enable ADC */
@@ -537,6 +541,7 @@ static int dln2_adc_triggered_buffer_postenable(struct iio_dev *indio_dev)
(int)conflict);
ret = -EBUSY;
}
+ iio_triggered_buffer_predisable(indio_dev);
return ret;
}

@@ -550,6 +555,7 @@ static int dln2_adc_triggered_buffer_postenable(struct iio_dev *indio_dev)
mutex_unlock(&dln2->mutex);
if (ret < 0) {
dev_dbg(&dln2->pdev->dev, "Problem in %s\n", __func__);
+ iio_triggered_buffer_predisable(indio_dev);
return ret;
}
} else {
@@ -557,12 +563,12 @@ static int dln2_adc_triggered_buffer_postenable(struct iio_dev *indio_dev)
mutex_unlock(&dln2->mutex);
}

- return iio_triggered_buffer_postenable(indio_dev);
+ return 0;
}

static int dln2_adc_triggered_buffer_predisable(struct iio_dev *indio_dev)
{
- int ret;
+ int ret, ret2;
struct dln2_adc *dln2 = iio_priv(indio_dev);

mutex_lock(&dln2->mutex);
@@ -577,12 +583,14 @@ static int dln2_adc_triggered_buffer_predisable(struct iio_dev *indio_dev)
ret = dln2_adc_set_port_enabled(dln2, false, NULL);

mutex_unlock(&dln2->mutex);
- if (ret < 0) {
+ if (ret < 0)
dev_dbg(&dln2->pdev->dev, "Problem in %s\n", __func__);
- return ret;
- }

- return iio_triggered_buffer_predisable(indio_dev);
+ ret2 = iio_triggered_buffer_predisable(indio_dev);
+ if (ret == 0)
+ ret = ret2;
+
+ return ret;
}

static const struct iio_buffer_setup_ops dln2_adc_buffer_setup_ops = {
--
2.20.1