[PATCH] iio: magnetometer: tlv493d: fix magnetic field scale

[PATCH] iio: magnetometer: tlv493d: fix magnetic field scale

[Viral Patel]

The TLV493D-A1B6 datasheet specifies a magnetic resolution of
98 uT/LSB (0.098 mT/LSB). IIO reports magnetic field in Gauss
(1 mT = 10 G), so the scale should be 0.98 G/LSB.

The driver currently reports 98/1000 = 0.098 G/LSB, which
under-reports the magnetic field by a factor of 10. The comment
also gives the resolution as 0.0098 mT (9.8 uT), mixing up units.

Correct the scale value and the comment.

Fixes: 106511d280c7 ("iio: magnetometer: add support for Infineon TLV493D 3D Magentic sensor")
Signed-off-by: Viral Patel <viral8854@gmail.com>
---
Found while comparing this driver against the TLE493D-W2B6 register
map for a new driver I am working on. Compile-tested only; I do not
have TLV493D-A1B6 hardware.
---
 drivers/iio/magnetometer/tlv493d.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/iio/magnetometer/tlv493d.c b/drivers/iio/magnetometer/tlv493d.c
index 03415cc2c9b3..234e3ce63ff7 100644
--- a/drivers/iio/magnetometer/tlv493d.c
+++ b/drivers/iio/magnetometer/tlv493d.c
@@ -299,11 +299,11 @@ static int tlv493d_read_raw(struct iio_dev *indio_dev,
 		switch (chan->type) {
 		case IIO_MAGN:
 			/*
-			 * Magnetic field scale: 0.0098 mTesla (i.e. 9.8 µT)
-			 * Magnetic field in Gauss: mT * 10 = 0.098.
+			 * Magnetic field scale: 0.098 mTesla (i.e. 98 µT) per LSB.
+			 * In Gauss (1 mT = 10 G): 0.98 G per LSB.
 			 */
 			*val = 98;
-			*val2 = 1000;
+			*val2 = 100;
 			return IIO_VAL_FRACTIONAL;
 		case IIO_TEMP:
 			/*

---
base-commit: ceb05f22e5cdc3f8bd3f7d5dcfc57843942191dd
change-id: 20261014-tlv493d-scale-fix-5a0b83b52d2a

Best regards,
-- 
Viral Patel <viral8854@gmail.com>

Re: [PATCH] iio: magnetometer: tlv493d: fix magnetic field scale

[Joshua Crofts]

On Wed, 14 Oct 2026 23:07:36 +0530
Viral Patel <viral8854@gmail.com> wrote:

> The TLV493D-A1B6 datasheet specifies a magnetic resolution of
> 98 uT/LSB (0.098 mT/LSB). IIO reports magnetic field in Gauss
> (1 mT = 10 G), so the scale should be 0.98 G/LSB.
> 
> The driver currently reports 98/1000 = 0.098 G/LSB, which
> under-reports the magnetic field by a factor of 10. The comment
> also gives the resolution as 0.0098 mT (9.8 uT), mixing up units.
> 
> Correct the scale value and the comment.
> 
> Fixes: 106511d280c7 ("iio: magnetometer: add support for Infineon TLV493D 3D Magentic sensor")
> Signed-off-by: Viral Patel <viral8854@gmail.com>
> ---

Good find.

Reviewed-by: Joshua Crofts <joshua.crofts1@gmail.com>

-- 
Kind regards,
Joshua Crofts