iio:adc:ad799x: Allow writing of event config

Allows explicity enabling of events

Previously, events were always reported as enabled, but actually only
implicitly enabled when updating the buffer scan mode

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

diff --git a/drivers/iio/adc/ad799x.c b/drivers/iio/adc/ad799x.c
index 08bcada394879858f34aaed60c055232d0034a6d..e37412da15f5c8ea300c7a096368d564a0acfba0 100644 (file)
--- a/drivers/iio/adc/ad799x.c
+++ b/drivers/iio/adc/ad799x.c
@@ -375,6 +375,39 @@ static int ad799x_read_event_config(struct iio_dev *indio_dev,
        return 0;
 }
 
+static int ad799x_write_event_config(struct iio_dev *indio_dev,
+                                    const struct iio_chan_spec *chan,
+                                    enum iio_event_type type,
+                                    enum iio_event_direction dir,
+                                    int state)
+{
+       struct ad799x_state *st = iio_priv(indio_dev);
+       int ret;
+
+       mutex_lock(&indio_dev->mlock);
+       if (iio_buffer_enabled(indio_dev)) {
+               ret = -EBUSY;
+               goto done;
+       }
+
+       if (state)
+               st->config |= BIT(chan->scan_index) << AD799X_CHANNEL_SHIFT;
+       else
+               st->config &= ~(BIT(chan->scan_index) << AD799X_CHANNEL_SHIFT);
+
+       if (st->config >> AD799X_CHANNEL_SHIFT)
+               st->config |= AD7998_ALERT_EN;
+       else
+               st->config &= ~AD7998_ALERT_EN;
+
+       ret = ad799x_write_config(st, st->config);
+
+done:
+       mutex_unlock(&indio_dev->mlock);
+
+       return ret;
+}
+
 static unsigned int ad799x_threshold_reg(const struct iio_chan_spec *chan,
                                         enum iio_event_direction dir,
                                         enum iio_event_info info)
@@ -502,6 +535,7 @@ static const struct iio_info ad7993_4_7_8_irq_info = {
        .read_raw = &ad799x_read_raw,
        .event_attrs = &ad799x_event_attrs_group,
        .read_event_config = &ad799x_read_event_config,
+       .write_event_config = &ad799x_write_event_config,
        .read_event_value = &ad799x_read_event_value,
        .write_event_value = &ad799x_write_event_value,
        .driver_module = THIS_MODULE,