[PATCH v2 5/8] iio: afe: rescale: add upstream offset support

From: Liam Beguin
Date: Mon Jun 07 2021 - 10:48:37 EST


From: Liam Beguin <lvb@xxxxxxxxxx>

Default to using iio_read_channel_processed() if the upstream channel
exposes an offset.

When possible, it's preferable to avoid using
iio_read_channel_processed() to maintain as much precision as possible.

Signed-off-by: Liam Beguin <lvb@xxxxxxxxxx>
---
drivers/iio/afe/iio-rescale.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/iio/afe/iio-rescale.c b/drivers/iio/afe/iio-rescale.c
index 774eb3044edd..e34148d39b39 100644
--- a/drivers/iio/afe/iio-rescale.c
+++ b/drivers/iio/afe/iio-rescale.c
@@ -148,7 +148,10 @@ static int rescale_configure_channel(struct device *dev,
chan->ext_info = rescale->ext_info;
chan->type = rescale->cfg->type;

- if (iio_channel_has_info(schan, IIO_CHAN_INFO_RAW) ||
+ if (iio_channel_has_info(schan, IIO_CHAN_INFO_OFFSET)) {
+ dev_info(dev, "found upstream offset, using processed value\n");
+ rescale->chan_processed = true;
+ } else if (iio_channel_has_info(schan, IIO_CHAN_INFO_RAW) ||
iio_channel_has_info(schan, IIO_CHAN_INFO_SCALE)) {
dev_info(dev, "using raw+scale source channel\n");
} else if (iio_channel_has_info(schan, IIO_CHAN_INFO_PROCESSED)) {
--
2.30.1.489.g328c10930387