On Fri,  1 Oct 2021 09:02:53 +0200
Roan van Dijk [off-list ref] wrote:

This is a driver for the SCD4x CO2 sensor from Sensirion. The sensor is
able to measure CO2 concentration, temperature and relative humdity.
The sensor uses a photoacoustic principle for measuring CO2 concentration.
An I2C interface is supported by this driver in order to communicate with
the sensor.

Signed-off-by: Roan van Dijk <roan@protonic.nl>

Hi Roan,

Looks like you sent out wrong version or similar as the trigger_handler
won't work as you have it here.  Otherwise looks good to me.

...

+static irqreturn_t scd4x_trigger_handler(int irq, void *p)
+{
+	struct iio_poll_func *pf = p;
+	struct iio_dev *indio_dev = pf->indio_dev;
+	struct scd4x_state *state = iio_priv(indio_dev);
+	struct {
+		uint16_t data[3];
+		int64_t ts __aligned(8);
+	} scan;
+	int ret;
+	uint16_t buf[3];
+
+	memset(&scan, 0, sizeof(scan));
+	mutex_lock(&state->lock);
+	ret = scd4x_read_poll(state, buf);

scan->data and drop the local variable buf as unused.

If I've interpreted the intent right here I'm happy to make this tweak
whilst applying.  If you prefer to send a v5 with it fixed up that is
fine as well.

+	mutex_unlock(&state->lock);
+	if (ret)
+		goto out;
+
+	iio_push_to_buffers_with_timestamp(indio_dev, &scan, iio_get_time_ns(indio_dev));
+out:
+	iio_trigger_notify_done(indio_dev->trig);
+	return IRQ_HANDLED;
+}
+

...