[PATCH v10 04/14] iio: afe: rescale: expose scale processing function

Liam Beguin
2021-12-19T22:40:17Z

In preparation for the addition of kunit tests, expose the logic
responsible for combining channel scales.

Signed-off-by: Liam Beguin <lvb@xiphos.com>
---
drivers/iio/afe/iio-rescale.c | 65 ++++++++++++++-------------------
include/linux/iio/afe/rescale.h | 30 +++++++++++++++
2 files changed, 58 insertions(+), 37 deletions(-)
create mode 100644 include/linux/iio/afe/rescale.h

diff --git a/drivers/iio/afe/iio-rescale.c b/drivers/iio/afe/iio-rescale.c
index 774eb3044edd..d0669fd8eac5 100644
--- a/drivers/iio/afe/iio-rescale.c
+++ b/drivers/iio/afe/iio-rescale.c
@@ -11,35 +11,46 @@
#include <linux/gcd.h>
#include <linux/iio/consumer.h>
#include <linux/iio/iio.h>
+#include <linux/iio/afe/rescale.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/property.h>

-struct rescale;
-
-struct rescale_cfg {
- enum iio_chan_type type;
- int (*props)(struct device *dev, struct rescale *rescale);
-};
+int rescale_process_scale(struct rescale *rescale, int scale_type,
+ int *val, int *val2)
+{
+ unsigned long long tmp;

-struct rescale {
- const struct rescale_cfg *cfg;
- struct iio_channel *source;
- struct iio_chan_spec chan;
- struct iio_chan_spec_ext_info *ext_info;
- bool chan_processed;
- s32 numerator;
- s32 denominator;
-};
+ switch (scale_type) {
+ case IIO_VAL_FRACTIONAL:
+ *val *= rescale->numerator;
+ *val2 *= rescale->denominator;
+ return scale_type;
+ case IIO_VAL_INT:
+ *val *= rescale->numerator;
+ if (rescale->denominator == 1)
+ return scale_type;
+ *val2 = rescale->denominator;
+ return IIO_VAL_FRACTIONAL;
+ case IIO_VAL_FRACTIONAL_LOG2:
+ tmp = *val * 1000000000LL;
+ do_div(tmp, rescale->denominator);
+ tmp *= rescale->numerator;
+ do_div(tmp, 1000000000LL);
+ *val = tmp;
+ return scale_type;
+ default:
+ return -EOPNOTSUPP;
+ }
+}

static int rescale_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long mask)
{
struct rescale *rescale = iio_priv(indio_dev);
- unsigned long long tmp;
int ret;

switch (mask) {
@@ -65,27 +76,7 @@ static int rescale_read_raw(struct iio_dev *indio_dev,
} else {
ret = iio_read_channel_scale(rescale->source, val, val2);
}
- switch (ret) {
- case IIO_VAL_FRACTIONAL:
- *val *= rescale->numerator;
- *val2 *= rescale->denominator;
- return ret;
- case IIO_VAL_INT:
- *val *= rescale->numerator;
- if (rescale->denominator == 1)
- return ret;
- *val2 = rescale->denominator;
- return IIO_VAL_FRACTIONAL;
- case IIO_VAL_FRACTIONAL_LOG2:
- tmp = *val * 1000000000LL;
- do_div(tmp, rescale->denominator);
- tmp *= rescale->numerator;
- do_div(tmp, 1000000000LL);
- *val = tmp;
- return ret;
- default:
- return -EOPNOTSUPP;
- }
+ return rescale_process_scale(rescale, ret, val, val2);
default:
return -EINVAL;
}
diff --git a/include/linux/iio/afe/rescale.h b/include/linux/iio/afe/rescale.h
new file mode 100644
index 000000000000..14d4ee1227c6
--- /dev/null
+++ b/include/linux/iio/afe/rescale.h
@@ -0,0 +1,30 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2021 Liam Beguin <liambeguin@gmail.com>
+ */
+
+#ifndef __IIO_RESCALE_H__
+#define __IIO_RESCALE_H__
+
+#include <linux/iio/iio.h>
+
+struct rescale;
+
+struct rescale_cfg {
+ enum iio_chan_type type;
+ int (*props)(struct device *dev, struct rescale *rescale);
+};
+
+struct rescale {
+ const struct rescale_cfg *cfg;
+ struct iio_channel *source;
+ struct iio_chan_spec chan;
+ struct iio_chan_spec_ext_info *ext_info;
+ bool chan_processed;
+ s32 numerator;
+ s32 denominator;
+};
+
+int rescale_process_scale(struct rescale *rescale, int scale_type,
+ int *val, int *val2);
+#endif /* __IIO_RESCALE_H__ */
--
2.34.0