[PATCH v2 0/6] iio: Introduce and use value of π

From: Andy Shevchenko

Date: Fri Nov 07 2025 - 15:10:17 EST


There are a few drivers that use value of π (small Greek PI)
of different precision. Instead of hard coding over and over
convert them to use a defined constant, which one of the patches
in this series introduces. No functional changes involved.

Note, the respective IIO macros are not converted yet by this series.

All of the converted files were checked in disassembled format before
and after the change to see that the value:
a) pre-calculated at compile-time;
b) is the same that is expected.

I didn't put the power-of-10 into the definition names as now they are
the maximum that fits the respective signed type.

Series is supposed to go via IIO tree.

Changelog v2:
- redone to avoid unneeded calculations
- collected tags (Hans)

v1: <20251027143850.2070427-1-andriy.shevchenko@xxxxxxxxxxxxxxx>

Andy Shevchenko (6):
media: vidtv: Rename PI definition to PI_SAMPLES
units: Add 32- and 64-bit signed values of π
media: dvb-frontends: atbm8830: Convert to use PI definition
iio: cros_ec_sensors: Convert to use PI definition
iio: frequency: ad9523: Convert to use PI definition
iio: position: iqs624-pos: Convert to use PI definition

drivers/iio/common/cros_ec_sensors/cros_ec_sensors.c | 3 ++-
drivers/iio/frequency/ad9523.c | 5 +++--
drivers/iio/position/iqs624-pos.c | 3 ++-
drivers/media/dvb-frontends/atbm8830.c | 5 +++--
drivers/media/test-drivers/vidtv/vidtv_s302m.c | 6 +++---
include/linux/units.h | 6 ++++++
6 files changed, 19 insertions(+), 9 deletions(-)

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2.50.1