drivers/iio/test/iio-test-multiply.c

Source file repositories/reference/linux-study-clean/drivers/iio/test/iio-test-multiply.c

File Facts

System
Linux kernel
Corpus path
drivers/iio/test/iio-test-multiply.c
Extension
.c
Size
6941 bytes
Lines
213
Domain
Driver Families
Bucket
drivers/iio
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0-only
/* Unit tests for IIO multiply functions
 *
 * Copyright (c) 2025 Hans de Goede <hans@hansg.org>
 * Based on iio-test-format.c which is:
 * Copyright (c) 2020 Lars-Peter Clausen <lars@metafoo.de>
 */

#include <kunit/test.h>
#include <linux/iio/consumer.h>
#include <linux/math64.h>
#include <linux/types.h>

static void __iio_test_iio_multiply_value_integer(struct kunit *test, s64 multiplier)
{
	int ret, result, val;

	val = 42;
	ret = iio_multiply_value(&result, multiplier, IIO_VAL_INT, val, 0);
	KUNIT_EXPECT_EQ(test, ret, IIO_VAL_INT);
	KUNIT_EXPECT_EQ(test, result, multiplier * val);

	val = -23;
	ret = iio_multiply_value(&result, multiplier, IIO_VAL_INT, val, 0);
	KUNIT_EXPECT_EQ(test, ret, IIO_VAL_INT);
	KUNIT_EXPECT_EQ(test, result, multiplier * val);

	val = 0;
	ret = iio_multiply_value(&result, multiplier, IIO_VAL_INT, val, 0);
	KUNIT_EXPECT_EQ(test, ret, IIO_VAL_INT);
	KUNIT_EXPECT_EQ(test, result, multiplier * val);
}

static void iio_test_iio_multiply_value_integer(struct kunit *test)
{
	__iio_test_iio_multiply_value_integer(test, 20);
	__iio_test_iio_multiply_value_integer(test, -20);
}

static void __iio_test_iio_multiply_value_fixedpoint(struct kunit *test, s64 multiplier)
{
	int ret, result, val, val2;

	/* positive >= 1 (1.5) */
	val = 1;
	val2 = 500000;
	ret = iio_multiply_value(&result, multiplier, IIO_VAL_INT_PLUS_MICRO, val, val2);
	KUNIT_EXPECT_EQ(test, ret, IIO_VAL_INT);
	KUNIT_EXPECT_EQ(test, result, div_s64(multiplier * 15, 10));

	val = 1;
	val2 = 500000000;
	ret = iio_multiply_value(&result, multiplier, IIO_VAL_INT_PLUS_NANO, val, val2);
	KUNIT_EXPECT_EQ(test, ret, IIO_VAL_INT);
	KUNIT_EXPECT_EQ(test, result, div_s64(multiplier * 15, 10));

	/* positive < 1 (0.5) */
	val = 0;
	val2 = 500000;
	ret = iio_multiply_value(&result, multiplier, IIO_VAL_INT_PLUS_MICRO, val, val2);
	KUNIT_EXPECT_EQ(test, ret, IIO_VAL_INT);
	KUNIT_EXPECT_EQ(test, result, div_s64(multiplier * 5, 10));

	val = 0;
	val2 = 500000000;
	ret = iio_multiply_value(&result, multiplier, IIO_VAL_INT_PLUS_NANO, val, val2);
	KUNIT_EXPECT_EQ(test, ret, IIO_VAL_INT);
	KUNIT_EXPECT_EQ(test, result, div_s64(multiplier * 5, 10));

	/* negative <= -1 (-1.5) */
	val = -1;
	val2 = 500000;
	ret = iio_multiply_value(&result, multiplier, IIO_VAL_INT_PLUS_MICRO, val, val2);
	KUNIT_EXPECT_EQ(test, ret, IIO_VAL_INT);
	KUNIT_EXPECT_EQ(test, result, div_s64(multiplier * -15, 10));

	val = -1;
	val2 = 500000000;
	ret = iio_multiply_value(&result, multiplier, IIO_VAL_INT_PLUS_NANO, val, val2);
	KUNIT_EXPECT_EQ(test, ret, IIO_VAL_INT);
	KUNIT_EXPECT_EQ(test, result, div_s64(multiplier * -15, 10));

	/* negative > -1 (-0.5) */
	val = 0;
	val2 = -500000;
	ret = iio_multiply_value(&result, multiplier, IIO_VAL_INT_PLUS_MICRO, val, val2);
	KUNIT_EXPECT_EQ(test, ret, IIO_VAL_INT);
	KUNIT_EXPECT_EQ(test, result, div_s64(multiplier * -5, 10));

	val = 0;

Annotation

Implementation Notes