From: Liam Beguin <liambeguin@gmail.com>
To: liambeguin@gmail.com, peda@axentia.se, jic23@kernel.org,
lars@metafoo.de, pmeerw@pmeerw.net
Cc: linux-kernel@vger.kernel.org, linux-iio@vger.kernel.org,
devicetree@vger.kernel.org, robh+dt@kernel.org
Subject: [PATCH v4 03/10] iio: inkern: make a best effort on offset calculation
Date: Tue, 6 Jul 2021 12:09:35 -0400 [thread overview]
Message-ID: <20210706160942.3181474-4-liambeguin@gmail.com> (raw)
In-Reply-To: <20210706160942.3181474-1-liambeguin@gmail.com>
From: Liam Beguin <lvb@xiphos.com>
iio_convert_raw_to_processed_unlocked() assumes the offset is an
integer. Make a best effort to get a valid offset value for fractional
cases without breaking implicit truncations.
Fixes: 48e44ce0f881 ("iio:inkern: Add function to read the processed value")
Signed-off-by: Liam Beguin <lvb@xiphos.com>
---
drivers/iio/inkern.c | 32 +++++++++++++++++++++++++++-----
1 file changed, 27 insertions(+), 5 deletions(-)
diff --git a/drivers/iio/inkern.c b/drivers/iio/inkern.c
index b69027690ed5..5e74d8983874 100644
--- a/drivers/iio/inkern.c
+++ b/drivers/iio/inkern.c
@@ -578,13 +578,35 @@ EXPORT_SYMBOL_GPL(iio_read_channel_average_raw);
static int iio_convert_raw_to_processed_unlocked(struct iio_channel *chan,
int raw, int *processed, unsigned int scale)
{
- int scale_type, scale_val, scale_val2, offset;
+ int scale_type, scale_val, scale_val2;
+ int offset_type, offset_val, offset_val2;
s64 raw64 = raw;
- int ret;
- ret = iio_channel_read(chan, &offset, NULL, IIO_CHAN_INFO_OFFSET);
- if (ret >= 0)
- raw64 += offset;
+ offset_type = iio_channel_read(chan, &offset_val, &offset_val2,
+ IIO_CHAN_INFO_OFFSET);
+ if (offset_type >= 0) {
+ switch (offset_type) {
+ case IIO_VAL_INT:
+ break;
+ case IIO_VAL_INT_PLUS_MICRO:
+ case IIO_VAL_INT_PLUS_NANO:
+ /*
+ * Both IIO_VAL_INT_PLUS_MICRO and IIO_VAL_INT_PLUS_NANO
+ * implicitely truncate the offset to it's integer form.
+ */
+ break;
+ case IIO_VAL_FRACTIONAL:
+ offset_val /= offset_val2;
+ break;
+ case IIO_VAL_FRACTIONAL_LOG2:
+ offset_val /= (1 << offset_val2);
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ raw64 += offset_val;
+ }
scale_type = iio_channel_read(chan, &scale_val, &scale_val2,
IIO_CHAN_INFO_SCALE);
--
2.30.1.489.g328c10930387
next prev parent reply other threads:[~2021-07-06 16:10 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-07-06 16:09 [PATCH v4 00/10] iio: afe: add temperature rescaling support Liam Beguin
2021-07-06 16:09 ` [PATCH v4 01/10] iio: inkern: apply consumer scale on IIO_VAL_INT cases Liam Beguin
2021-07-06 16:09 ` [PATCH v4 02/10] iio: inkern: apply consumer scale when no channel scale is available Liam Beguin
2021-07-06 16:09 ` Liam Beguin [this message]
2021-07-06 16:09 ` [PATCH v4 04/10] iio: afe: rescale: reduce risk of integer overflow Liam Beguin
2021-07-09 16:24 ` Peter Rosin
2021-07-09 19:22 ` Liam Beguin
2021-07-06 16:09 ` [PATCH v4 05/10] iio: afe: rescale: add INT_PLUS_{MICRO,NANO} support Liam Beguin
2021-07-09 16:29 ` Peter Rosin
2021-07-09 19:30 ` Liam Beguin
2021-07-10 8:14 ` Peter Rosin
2021-07-10 17:45 ` Liam Beguin
2021-07-06 16:09 ` [PATCH v4 06/10] iio: afe: rescale: add offset support Liam Beguin
2021-07-06 16:09 ` [PATCH v4 07/10] iio: afe: rescale: add RTD temperature sensor support Liam Beguin
2021-07-06 16:09 ` [PATCH v4 08/10] iio: afe: rescale: add temperature transducers Liam Beguin
2021-07-06 16:09 ` [PATCH v4 09/10] dt-bindings: iio: afe: add bindings for temperature-sense-rtd Liam Beguin
2021-07-12 16:08 ` Rob Herring
2021-07-06 16:09 ` [PATCH v4 10/10] dt-bindings: iio: afe: add bindings for temperature transducers Liam Beguin
2021-07-12 16:11 ` Rob Herring
2021-07-13 4:20 ` Liam Beguin
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