iio: Move attach/detach of the poll func to the core

All devices using a triggered buffer need to attach and detach the trigger
to the device in order to properly work. Instead of doing this in each and
every driver by hand move this into the core.

At this point in time, all drivers should have been resolved to
attach/detach the poll-function in the same order.

This patch removes all explicit calls of iio_triggered_buffer_postenable()
& iio_triggered_buffer_predisable() in all drivers, since the core handles
now the pollfunc attach/detach.

The more peculiar change is for the 'at91-sama5d2_adc' driver, since it's
not immediately obvious that removing the hooks doesn't break anything.
Eugen was able to test on at91-sama5d2-adc driver, sama5d2-xplained board.
All seems to be fine.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Tested-by: Eugen Hristev <eugen.hristev@microchip.com> #for at91-sama5d2-adc
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

2 files changed, 12 insertions, 41 deletions

diff --git a/drivers/iio/pressure/st_pressure_buffer.c b/drivers/iio/pressure/st_pressure_buffer.c
index 418dbf9e6e1e..7cf6f06797e1 100644
--- a/drivers/iio/pressure/st_pressure_buffer.c
+++ b/drivers/iio/pressure/st_pressure_buffer.c
@@ -31,34 +31,12 @@ int st_press_trig_set_state(struct iio_trigger *trig, bool state)
 
 static int st_press_buffer_postenable(struct iio_dev *indio_dev)
 {
-	int err;
-
-	err = iio_triggered_buffer_postenable(indio_dev);
-	if (err < 0)
-		return err;
-
-	err = st_sensors_set_enable(indio_dev, true);
-	if (err < 0)
-		goto st_press_buffer_predisable;
-
-	return 0;
-
-st_press_buffer_predisable:
-	iio_triggered_buffer_predisable(indio_dev);
-	return err;
+	return st_sensors_set_enable(indio_dev, true);
 }
 
 static int st_press_buffer_predisable(struct iio_dev *indio_dev)
 {
-	int err, err2;
-
-	err = st_sensors_set_enable(indio_dev, false);
-
-	err2 = iio_triggered_buffer_predisable(indio_dev);
-	if (!err)
-		err = err2;
-
-	return err;
+	return st_sensors_set_enable(indio_dev, false);
 }
 
 static const struct iio_buffer_setup_ops st_press_buffer_setup_ops = {
diff --git a/drivers/iio/pressure/zpa2326.c b/drivers/iio/pressure/zpa2326.c
index ef818f2aebd6..2b8796ef91ef 100644
--- a/drivers/iio/pressure/zpa2326.c
+++ b/drivers/iio/pressure/zpa2326.c
@@ -1242,19 +1242,17 @@ static int zpa2326_postenable_buffer(struct iio_dev *indio_dev)
 	const struct zpa2326_private *priv = iio_priv(indio_dev);
 	int                           err;
 
-	/* Plug our own trigger event handler. */
-	err = iio_triggered_buffer_postenable(indio_dev);
-	if (err)
-		goto err;
-
 	if (!priv->waken) {
 		/*
 		 * We were already power supplied. Just clear hardware FIFO to
 		 * get rid of samples acquired during previous rounds (if any).
 		 */
 		err = zpa2326_clear_fifo(indio_dev, 0);
-		if (err)
-			goto err_buffer_predisable;
+		if (err) {
+			zpa2326_err(indio_dev,
+				    "failed to enable buffering (%d)", err);
+			return err;
+		}
 	}
 
 	if (!iio_trigger_using_own(indio_dev) && priv->waken) {
@@ -1263,18 +1261,14 @@ static int zpa2326_postenable_buffer(struct iio_dev *indio_dev)
 		 * powered up: reconfigure one-shot mode.
 		 */
 		err = zpa2326_config_oneshot(indio_dev, priv->irq);
-		if (err)
-			goto err_buffer_predisable;
+		if (err) {
+			zpa2326_err(indio_dev,
+				    "failed to enable buffering (%d)", err);
+			return err;
+		}
 	}
 
 	return 0;
-
-err_buffer_predisable:
-	iio_triggered_buffer_predisable(indio_dev);
-err:
-	zpa2326_err(indio_dev, "failed to enable buffering (%d)", err);
-
-	return err;
 }
 
 static int zpa2326_postdisable_buffer(struct iio_dev *indio_dev)
@@ -1287,7 +1281,6 @@ static int zpa2326_postdisable_buffer(struct iio_dev *indio_dev)
 static const struct iio_buffer_setup_ops zpa2326_buffer_setup_ops = {
 	.preenable   = zpa2326_preenable_buffer,
 	.postenable  = zpa2326_postenable_buffer,
-	.predisable  = iio_triggered_buffer_predisable,
 	.postdisable = zpa2326_postdisable_buffer
 };