--- zzzz-none-000/linux-3.10.107/drivers/iio/adc/ad7791.c	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/drivers/iio/adc/ad7791.c	2021-02-04 17:41:59.000000000 +0000
@@ -202,7 +202,6 @@
 {
 	struct ad7791_state *st = iio_priv(indio_dev);
 	bool unipolar = !!(st->mode & AD7791_MODE_UNIPOLAR);
-	unsigned long long scale_pv;
 
 	switch (info) {
 	case IIO_CHAN_INFO_RAW:
@@ -220,23 +219,26 @@
 	case IIO_CHAN_INFO_SCALE:
 		/* The monitor channel uses an internal reference. */
 		if (chan->address == AD7791_CH_AVDD_MONITOR) {
-			scale_pv = 5850000000000ULL;
+			/*
+			 * The signal is attenuated by a factor of 5 and
+			 * compared against a 1.17V internal reference.
+			 */
+			*val = 1170 * 5;
 		} else {
 			int voltage_uv;
 
 			voltage_uv = regulator_get_voltage(st->reg);
 			if (voltage_uv < 0)
 				return voltage_uv;
-			scale_pv = (unsigned long long)voltage_uv * 1000000;
+
+			*val = voltage_uv / 1000;
 		}
 		if (unipolar)
-			scale_pv >>= chan->scan_type.realbits;
+			*val2 = chan->scan_type.realbits;
 		else
-			scale_pv >>= chan->scan_type.realbits - 1;
-		*val2 = do_div(scale_pv, 1000000000);
-		*val = scale_pv;
+			*val2 = chan->scan_type.realbits - 1;
 
-		return IIO_VAL_INT_PLUS_NANO;
+		return IIO_VAL_FRACTIONAL_LOG2;
 	}
 
 	return -EINVAL;
@@ -361,21 +363,19 @@
 		return -ENXIO;
 	}
 
-	indio_dev = iio_device_alloc(sizeof(*st));
+	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
 	if (!indio_dev)
 		return -ENOMEM;
 
 	st = iio_priv(indio_dev);
 
-	st->reg = regulator_get(&spi->dev, "refin");
-	if (IS_ERR(st->reg)) {
-		ret = PTR_ERR(st->reg);
-		goto err_iio_free;
-	}
+	st->reg = devm_regulator_get(&spi->dev, "refin");
+	if (IS_ERR(st->reg))
+		return PTR_ERR(st->reg);
 
 	ret = regulator_enable(st->reg);
 	if (ret)
-		goto error_put_reg;
+		return ret;
 
 	st->info = &ad7791_chip_infos[spi_get_device_id(spi)->driver_data];
 	ad_sd_init(&st->sd, indio_dev, spi, &ad7791_sigma_delta_info);
@@ -410,10 +410,6 @@
 	ad_sd_cleanup_buffer_and_trigger(indio_dev);
 error_disable_reg:
 	regulator_disable(st->reg);
-error_put_reg:
-	regulator_put(st->reg);
-err_iio_free:
-	iio_device_free(indio_dev);
 
 	return ret;
 }
@@ -427,9 +423,6 @@
 	ad_sd_cleanup_buffer_and_trigger(indio_dev);
 
 	regulator_disable(st->reg);
-	regulator_put(st->reg);
-
-	iio_device_free(indio_dev);
 
 	return 0;
 }
@@ -447,7 +440,6 @@
 static struct spi_driver ad7791_driver = {
 	.driver = {
 		.name	= "ad7791",
-		.owner	= THIS_MODULE,
 	},
 	.probe		= ad7791_probe,
 	.remove		= ad7791_remove,