iio: adc: ad_sigma_delta: allow overwriting the IRQ flags

Make sure we can specify the IRQ trigger type from firmware and drivers
won't ignore it. In fact, this how it should be done but since someone
might be already depending on the driver to hardcode the trigger type
(and not specifying it in firmware), let's do it like this so there's
no possible breakage.
Signed-off-by: Nuno Sa <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20240117-dev_sigma_delta_no_irq_flags-v1-2-db39261592cf@analog.comSigned-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/adc/ad_sigma_delta.c

@@ -568,6 +568,7 @@ EXPORT_SYMBOL_NS_GPL(ad_sd_validate_trigger, IIO_AD_SIGMA_DELTA);
 static int devm_ad_sd_probe_trigger(struct device *dev, struct iio_dev *indio_dev)
 {
 	struct ad_sigma_delta *sigma_delta = iio_device_get_drvdata(indio_dev);
+	unsigned long irq_flags = irq_get_trigger_type(sigma_delta->spi->irq);
 	int ret;
 
 	if (dev != &sigma_delta->spi->dev) {
@@ -588,9 +589,13 @@ static int devm_ad_sd_probe_trigger(struct device *dev, struct iio_dev *indio_de
 	/* the IRQ core clears IRQ_DISABLE_UNLAZY flag when freeing an IRQ */
 	irq_set_status_flags(sigma_delta->spi->irq, IRQ_DISABLE_UNLAZY);
 
+	/* Allow overwriting the flags from firmware */
+	if (!irq_flags)
+		irq_flags = sigma_delta->info->irq_flags;
+
 	ret = devm_request_irq(dev, sigma_delta->spi->irq,
 			       ad_sd_data_rdy_trig_poll,
-			       sigma_delta->info->irq_flags | IRQF_NO_AUTOEN,
+			       irq_flags | IRQF_NO_AUTOEN,
 			       indio_dev->name,
 			       sigma_delta);
 	if (ret)