[PATCH v4 1/4] math.h: Introduce data types for fractional numbers

[PATCH v4 1/4] math.h: Introduce data types for fractional numbers

[Andy Shevchenko]

Introduce a macro to produce data types like

	struct TYPE_fract {
		__TYPE numerator;
		__TYPE denominator;
	};

to be used in the code wherever it's needed.

In the following changes convert some users to it.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---

May be pulled via IIO tree.

v4: no changes
v3: no changes
v2: no changes

 include/linux/math.h | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/include/linux/math.h b/include/linux/math.h
index 53674a327e39..439b8f0b9ebd 100644
--- a/include/linux/math.h
+++ b/include/linux/math.h
@@ -2,6 +2,7 @@
 #ifndef _LINUX_MATH_H
 #define _LINUX_MATH_H
 
+#include <linux/types.h>
 #include <asm/div64.h>
 #include <uapi/linux/kernel.h>
 
@@ -106,6 +107,17 @@
 }							\
 )
 
+#define __STRUCT_FRACT(type)				\
+struct type##_fract {					\
+	__##type numerator;				\
+	__##type denominator;				\
+};
+__STRUCT_FRACT(s16)
+__STRUCT_FRACT(u16)
+__STRUCT_FRACT(s32)
+__STRUCT_FRACT(u32)
+#undef __STRUCT_FRACT
+
 /*
  * Multiplies an integer by a fraction, while avoiding unnecessary
  * overflow or loss of precision.
-- 
2.34.1

[PATCH v4 2/4] iio: adc: rn5t618: Re-use generic struct u16_fract

[Andy Shevchenko]

Instead of custom data type re-use generic struct u16_fract.
No changes intended.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---

v4: no changes
v3: no changes
v2: no changes

 drivers/iio/adc/rn5t618-adc.c | 7 +------
 1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/drivers/iio/adc/rn5t618-adc.c b/drivers/iio/adc/rn5t618-adc.c
index 7d891b4ea461..6bf32907f01d 100644
--- a/drivers/iio/adc/rn5t618-adc.c
+++ b/drivers/iio/adc/rn5t618-adc.c
@@ -42,11 +42,6 @@ struct rn5t618_adc_data {
 	int irq;
 };
 
-struct rn5t618_channel_ratios {
-	u16 numerator;
-	u16 denominator;
-};
-
 enum rn5t618_channels {
 	LIMMON = 0,
 	VBAT,
@@ -58,7 +53,7 @@ enum rn5t618_channels {
 	AIN0
 };
 
-static const struct rn5t618_channel_ratios rn5t618_ratios[8] = {
+static const struct u16_fract rn5t618_ratios[8] = {
 	[LIMMON] = {50, 32}, /* measured across 20mOhm, amplified by 32 */
 	[VBAT] = {2, 1},
 	[VADP] = {3, 1},
-- 
2.34.1

[PATCH v4 3/4] iio: adc: twl4030-madc: Re-use generic struct s16_fract

[Andy Shevchenko]

Instead of custom data type re-use generic struct s16_fract.
No changes intended.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---

v4: no changes
v3: no changes
v2: no changes

 drivers/iio/adc/twl4030-madc.c | 9 +--------
 1 file changed, 1 insertion(+), 8 deletions(-)

diff --git a/drivers/iio/adc/twl4030-madc.c b/drivers/iio/adc/twl4030-madc.c
index 6ce40cc4568a..f8f8aea15612 100644
--- a/drivers/iio/adc/twl4030-madc.c
+++ b/drivers/iio/adc/twl4030-madc.c
@@ -231,13 +231,7 @@ static const struct iio_chan_spec twl4030_madc_iio_channels[] = {
 
 static struct twl4030_madc_data *twl4030_madc;
 
-struct twl4030_prescale_divider_ratios {
-	s16 numerator;
-	s16 denominator;
-};
-
-static const struct twl4030_prescale_divider_ratios
-twl4030_divider_ratios[16] = {
+static const struct s16_fract twl4030_divider_ratios[16] = {
 	{1, 1},		/* CHANNEL 0 No Prescaler */
 	{1, 1},		/* CHANNEL 1 No Prescaler */
 	{6, 10},	/* CHANNEL 2 */
@@ -256,7 +250,6 @@ twl4030_divider_ratios[16] = {
 	{5, 11},	/* CHANNEL 15 */
 };
 
-
 /* Conversion table from -3 to 55 degrees Celcius */
 static int twl4030_therm_tbl[] = {
 	30800,	29500,	28300,	27100,
-- 
2.34.1

[PATCH v4 4/4] iio: adc: qcom-vadc-common: Re-use generic struct u32_fract

[Andy Shevchenko]

Instead of custom data type re-use generic struct u32_fract.
No changes intended.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---

v4: no changes
v3: no changes
v2: comile-tested, i.o.w. fixed compilation errors

 drivers/iio/adc/qcom-pm8xxx-xoadc.c      | 15 ++--
 drivers/iio/adc/qcom-spmi-vadc.c         | 24 +++----
 drivers/iio/adc/qcom-vadc-common.c       | 92 ++++++++++++------------
 include/linux/iio/adc/qcom-vadc-common.h | 15 +---
 4 files changed, 69 insertions(+), 77 deletions(-)

diff --git a/drivers/iio/adc/qcom-pm8xxx-xoadc.c b/drivers/iio/adc/qcom-pm8xxx-xoadc.c
index 21d7eff645c3..5e9e56821075 100644
--- a/drivers/iio/adc/qcom-pm8xxx-xoadc.c
+++ b/drivers/iio/adc/qcom-pm8xxx-xoadc.c
@@ -175,7 +175,7 @@ struct xoadc_channel {
 	const char *datasheet_name;
 	u8 pre_scale_mux:2;
 	u8 amux_channel:4;
-	const struct vadc_prescale_ratio prescale;
+	const struct u32_fract prescale;
 	enum iio_chan_type type;
 	enum vadc_scale_fn_type scale_fn_type;
 	u8 amux_ip_rsv:3;
@@ -218,7 +218,9 @@ struct xoadc_variant {
 		.datasheet_name = __stringify(_dname),			\
 		.pre_scale_mux = _presmux,				\
 		.amux_channel = _amux,					\
-		.prescale = { .num = _prenum, .den = _preden },		\
+		.prescale = {						\
+			.numerator = _prenum, .denominator = _preden,	\
+		},							\
 		.type = _type,						\
 		.scale_fn_type = _scale,				\
 		.amux_ip_rsv = _amip,					\
@@ -809,12 +811,11 @@ static int pm8xxx_xoadc_parse_channel(struct device *dev,
 		BIT(IIO_CHAN_INFO_PROCESSED);
 	iio_chan->indexed = 1;
 
-	dev_dbg(dev, "channel [PRESCALE/MUX: %02x AMUX: %02x] \"%s\" "
-		"ref voltage: %d, decimation %d "
-		"prescale %d/%d, scale function %d\n",
+	dev_dbg(dev,
+		"channel [PRESCALE/MUX: %02x AMUX: %02x] \"%s\" ref voltage: %d, decimation %d prescale %d/%d, scale function %d\n",
 		hwchan->pre_scale_mux, hwchan->amux_channel, ch->name,
-		ch->amux_ip_rsv, ch->decimation, hwchan->prescale.num,
-		hwchan->prescale.den, hwchan->scale_fn_type);
+		ch->amux_ip_rsv, ch->decimation, hwchan->prescale.numerator,
+		hwchan->prescale.denominator, hwchan->scale_fn_type);
 
 	return 0;
 }
diff --git a/drivers/iio/adc/qcom-spmi-vadc.c b/drivers/iio/adc/qcom-spmi-vadc.c
index 07b1a99381d9..34202ba52469 100644
--- a/drivers/iio/adc/qcom-spmi-vadc.c
+++ b/drivers/iio/adc/qcom-spmi-vadc.c
@@ -122,15 +122,15 @@ struct vadc_priv {
 	struct mutex		 lock;
 };
 
-static const struct vadc_prescale_ratio vadc_prescale_ratios[] = {
-	{.num =  1, .den =  1},
-	{.num =  1, .den =  3},
-	{.num =  1, .den =  4},
-	{.num =  1, .den =  6},
-	{.num =  1, .den = 20},
-	{.num =  1, .den =  8},
-	{.num = 10, .den = 81},
-	{.num =  1, .den = 10}
+static const struct u32_fract vadc_prescale_ratios[] = {
+	{ .numerator =  1, .denominator =  1 },
+	{ .numerator =  1, .denominator =  3 },
+	{ .numerator =  1, .denominator =  4 },
+	{ .numerator =  1, .denominator =  6 },
+	{ .numerator =  1, .denominator = 20 },
+	{ .numerator =  1, .denominator =  8 },
+	{ .numerator = 10, .denominator = 81 },
+	{ .numerator =  1, .denominator = 10 },
 };
 
 static int vadc_read(struct vadc_priv *vadc, u16 offset, u8 *data)
@@ -404,13 +404,13 @@ static int vadc_measure_ref_points(struct vadc_priv *vadc)
 	return ret;
 }
 
-static int vadc_prescaling_from_dt(u32 num, u32 den)
+static int vadc_prescaling_from_dt(u32 numerator, u32 denominator)
 {
 	unsigned int pre;
 
 	for (pre = 0; pre < ARRAY_SIZE(vadc_prescale_ratios); pre++)
-		if (vadc_prescale_ratios[pre].num == num &&
-		    vadc_prescale_ratios[pre].den == den)
+		if (vadc_prescale_ratios[pre].numerator == numerator &&
+		    vadc_prescale_ratios[pre].denominator == denominator)
 			break;
 
 	if (pre == ARRAY_SIZE(vadc_prescale_ratios))
diff --git a/drivers/iio/adc/qcom-vadc-common.c b/drivers/iio/adc/qcom-vadc-common.c
index 14723896aab2..6c6aec848f98 100644
--- a/drivers/iio/adc/qcom-vadc-common.c
+++ b/drivers/iio/adc/qcom-vadc-common.c
@@ -289,44 +289,44 @@ static const struct vadc_map_pt adcmap7_100k[] = {
 	{ 2420, 130048 }
 };
 
-static const struct vadc_prescale_ratio adc5_prescale_ratios[] = {
-	{.num =  1, .den =  1},
-	{.num =  1, .den =  3},
-	{.num =  1, .den =  4},
-	{.num =  1, .den =  6},
-	{.num =  1, .den = 20},
-	{.num =  1, .den =  8},
-	{.num = 10, .den = 81},
-	{.num =  1, .den = 10},
-	{.num =  1, .den = 16}
+static const struct u32_fract adc5_prescale_ratios[] = {
+	{ .numerator =  1, .denominator =  1 },
+	{ .numerator =  1, .denominator =  3 },
+	{ .numerator =  1, .denominator =  4 },
+	{ .numerator =  1, .denominator =  6 },
+	{ .numerator =  1, .denominator = 20 },
+	{ .numerator =  1, .denominator =  8 },
+	{ .numerator = 10, .denominator = 81 },
+	{ .numerator =  1, .denominator = 10 },
+	{ .numerator =  1, .denominator = 16 },
 };
 
 static int qcom_vadc_scale_hw_calib_volt(
-				const struct vadc_prescale_ratio *prescale,
+				const struct u32_fract *prescale,
 				const struct adc5_data *data,
 				u16 adc_code, int *result_uv);
 static int qcom_vadc_scale_hw_calib_therm(
-				const struct vadc_prescale_ratio *prescale,
+				const struct u32_fract *prescale,
 				const struct adc5_data *data,
 				u16 adc_code, int *result_mdec);
 static int qcom_vadc7_scale_hw_calib_therm(
-				const struct vadc_prescale_ratio *prescale,
+				const struct u32_fract *prescale,
 				const struct adc5_data *data,
 				u16 adc_code, int *result_mdec);
 static int qcom_vadc_scale_hw_smb_temp(
-				const struct vadc_prescale_ratio *prescale,
+				const struct u32_fract *prescale,
 				const struct adc5_data *data,
 				u16 adc_code, int *result_mdec);
 static int qcom_vadc_scale_hw_chg5_temp(
-				const struct vadc_prescale_ratio *prescale,
+				const struct u32_fract *prescale,
 				const struct adc5_data *data,
 				u16 adc_code, int *result_mdec);
 static int qcom_vadc_scale_hw_calib_die_temp(
-				const struct vadc_prescale_ratio *prescale,
+				const struct u32_fract *prescale,
 				const struct adc5_data *data,
 				u16 adc_code, int *result_mdec);
 static int qcom_vadc7_scale_hw_calib_die_temp(
-				const struct vadc_prescale_ratio *prescale,
+				const struct u32_fract *prescale,
 				const struct adc5_data *data,
 				u16 adc_code, int *result_mdec);
 
@@ -406,7 +406,7 @@ static void qcom_vadc_scale_calib(const struct vadc_linear_graph *calib_graph,
 }
 
 static int qcom_vadc_scale_volt(const struct vadc_linear_graph *calib_graph,
-				const struct vadc_prescale_ratio *prescale,
+				const struct u32_fract *prescale,
 				bool absolute, u16 adc_code,
 				int *result_uv)
 {
@@ -414,15 +414,15 @@ static int qcom_vadc_scale_volt(const struct vadc_linear_graph *calib_graph,
 
 	qcom_vadc_scale_calib(calib_graph, adc_code, absolute, &voltage);
 
-	voltage = voltage * prescale->den;
-	result = div64_s64(voltage, prescale->num);
+	voltage *= prescale->denominator;
+	result = div64_s64(voltage, prescale->numerator);
 	*result_uv = result;
 
 	return 0;
 }
 
 static int qcom_vadc_scale_therm(const struct vadc_linear_graph *calib_graph,
-				 const struct vadc_prescale_ratio *prescale,
+				 const struct u32_fract *prescale,
 				 bool absolute, u16 adc_code,
 				 int *result_mdec)
 {
@@ -444,7 +444,7 @@ static int qcom_vadc_scale_therm(const struct vadc_linear_graph *calib_graph,
 }
 
 static int qcom_vadc_scale_die_temp(const struct vadc_linear_graph *calib_graph,
-				    const struct vadc_prescale_ratio *prescale,
+				    const struct u32_fract *prescale,
 				    bool absolute,
 				    u16 adc_code, int *result_mdec)
 {
@@ -454,8 +454,8 @@ static int qcom_vadc_scale_die_temp(const struct vadc_linear_graph *calib_graph,
 	qcom_vadc_scale_calib(calib_graph, adc_code, absolute, &voltage);
 
 	if (voltage > 0) {
-		temp = voltage * prescale->den;
-		do_div(temp, prescale->num * 2);
+		temp = voltage * prescale->denominator;
+		do_div(temp, prescale->numerator * 2);
 		voltage = temp;
 	} else {
 		voltage = 0;
@@ -467,7 +467,7 @@ static int qcom_vadc_scale_die_temp(const struct vadc_linear_graph *calib_graph,
 }
 
 static int qcom_vadc_scale_chg_temp(const struct vadc_linear_graph *calib_graph,
-				    const struct vadc_prescale_ratio *prescale,
+				    const struct u32_fract *prescale,
 				    bool absolute,
 				    u16 adc_code, int *result_mdec)
 {
@@ -475,8 +475,8 @@ static int qcom_vadc_scale_chg_temp(const struct vadc_linear_graph *calib_graph,
 
 	qcom_vadc_scale_calib(calib_graph, adc_code, absolute, &voltage);
 
-	voltage = voltage * prescale->den;
-	voltage = div64_s64(voltage, prescale->num);
+	voltage *= prescale->denominator;
+	voltage = div64_s64(voltage, prescale->numerator);
 	voltage = ((PMI_CHG_SCALE_1) * (voltage * 2));
 	voltage = (voltage + PMI_CHG_SCALE_2);
 	result =  div64_s64(voltage, 1000000);
@@ -487,21 +487,21 @@ static int qcom_vadc_scale_chg_temp(const struct vadc_linear_graph *calib_graph,
 
 /* convert voltage to ADC code, using 1.875V reference */
 static u16 qcom_vadc_scale_voltage_code(s32 voltage,
-					const struct vadc_prescale_ratio *prescale,
+					const struct u32_fract *prescale,
 					const u32 full_scale_code_volt,
 					unsigned int factor)
 {
 	s64 volt = voltage;
 	s64 adc_vdd_ref_mv = 1875; /* reference voltage */
 
-	volt *= prescale->num * factor * full_scale_code_volt;
-	volt = div64_s64(volt, (s64)prescale->den * adc_vdd_ref_mv * 1000);
+	volt *= prescale->numerator * factor * full_scale_code_volt;
+	volt = div64_s64(volt, (s64)prescale->denominator * adc_vdd_ref_mv * 1000);
 
 	return volt;
 }
 
 static int qcom_vadc_scale_code_voltage_factor(u16 adc_code,
-				const struct vadc_prescale_ratio *prescale,
+				const struct u32_fract *prescale,
 				const struct adc5_data *data,
 				unsigned int factor)
 {
@@ -520,8 +520,8 @@ static int qcom_vadc_scale_code_voltage_factor(u16 adc_code,
 	voltage = (s64) adc_code * adc_vdd_ref_mv * 1000;
 	voltage = div64_s64(voltage, data->full_scale_code_volt);
 	if (voltage > 0) {
-		voltage *= prescale->den;
-		temp = prescale->num * factor;
+		voltage *= prescale->denominator;
+		temp = prescale->numerator * factor;
 		voltage = div64_s64(voltage, temp);
 	} else {
 		voltage = 0;
@@ -531,7 +531,7 @@ static int qcom_vadc_scale_code_voltage_factor(u16 adc_code,
 }
 
 static int qcom_vadc7_scale_hw_calib_therm(
-				const struct vadc_prescale_ratio *prescale,
+				const struct u32_fract *prescale,
 				const struct adc5_data *data,
 				u16 adc_code, int *result_mdec)
 {
@@ -557,7 +557,7 @@ static int qcom_vadc7_scale_hw_calib_therm(
 }
 
 static int qcom_vadc_scale_hw_calib_volt(
-				const struct vadc_prescale_ratio *prescale,
+				const struct u32_fract *prescale,
 				const struct adc5_data *data,
 				u16 adc_code, int *result_uv)
 {
@@ -568,7 +568,7 @@ static int qcom_vadc_scale_hw_calib_volt(
 }
 
 static int qcom_vadc_scale_hw_calib_therm(
-				const struct vadc_prescale_ratio *prescale,
+				const struct u32_fract *prescale,
 				const struct adc5_data *data,
 				u16 adc_code, int *result_mdec)
 {
@@ -584,7 +584,7 @@ static int qcom_vadc_scale_hw_calib_therm(
 }
 
 static int qcom_vadc_scale_hw_calib_die_temp(
-				const struct vadc_prescale_ratio *prescale,
+				const struct u32_fract *prescale,
 				const struct adc5_data *data,
 				u16 adc_code, int *result_mdec)
 {
@@ -596,7 +596,7 @@ static int qcom_vadc_scale_hw_calib_die_temp(
 }
 
 static int qcom_vadc7_scale_hw_calib_die_temp(
-				const struct vadc_prescale_ratio *prescale,
+				const struct u32_fract *prescale,
 				const struct adc5_data *data,
 				u16 adc_code, int *result_mdec)
 {
@@ -611,7 +611,7 @@ static int qcom_vadc7_scale_hw_calib_die_temp(
 }
 
 static int qcom_vadc_scale_hw_smb_temp(
-				const struct vadc_prescale_ratio *prescale,
+				const struct u32_fract *prescale,
 				const struct adc5_data *data,
 				u16 adc_code, int *result_mdec)
 {
@@ -623,7 +623,7 @@ static int qcom_vadc_scale_hw_smb_temp(
 }
 
 static int qcom_vadc_scale_hw_chg5_temp(
-				const struct vadc_prescale_ratio *prescale,
+				const struct u32_fract *prescale,
 				const struct adc5_data *data,
 				u16 adc_code, int *result_mdec)
 {
@@ -636,7 +636,7 @@ static int qcom_vadc_scale_hw_chg5_temp(
 
 int qcom_vadc_scale(enum vadc_scale_fn_type scaletype,
 		    const struct vadc_linear_graph *calib_graph,
-		    const struct vadc_prescale_ratio *prescale,
+		    const struct u32_fract *prescale,
 		    bool absolute,
 		    u16 adc_code, int *result)
 {
@@ -667,7 +667,7 @@ EXPORT_SYMBOL(qcom_vadc_scale);
 u16 qcom_adc_tm5_temp_volt_scale(unsigned int prescale_ratio,
 				 u32 full_scale_code_volt, int temp)
 {
-	const struct vadc_prescale_ratio *prescale = &adc5_prescale_ratios[prescale_ratio];
+	const struct u32_fract *prescale = &adc5_prescale_ratios[prescale_ratio];
 	s32 voltage;
 
 	voltage = qcom_vadc_map_temp_voltage(adcmap_100k_104ef_104fb_1875_vref,
@@ -682,7 +682,7 @@ int qcom_adc5_hw_scale(enum vadc_scale_fn_type scaletype,
 		    const struct adc5_data *data,
 		    u16 adc_code, int *result)
 {
-	const struct vadc_prescale_ratio *prescale = &adc5_prescale_ratios[prescale_ratio];
+	const struct u32_fract *prescale = &adc5_prescale_ratios[prescale_ratio];
 
 	if (!(scaletype >= SCALE_HW_CALIB_DEFAULT &&
 		scaletype < SCALE_HW_CALIB_INVALID)) {
@@ -695,13 +695,13 @@ int qcom_adc5_hw_scale(enum vadc_scale_fn_type scaletype,
 }
 EXPORT_SYMBOL(qcom_adc5_hw_scale);
 
-int qcom_adc5_prescaling_from_dt(u32 num, u32 den)
+int qcom_adc5_prescaling_from_dt(u32 numerator, u32 denominator)
 {
 	unsigned int pre;
 
 	for (pre = 0; pre < ARRAY_SIZE(adc5_prescale_ratios); pre++)
-		if (adc5_prescale_ratios[pre].num == num &&
-		    adc5_prescale_ratios[pre].den == den)
+		if (adc5_prescale_ratios[pre].numerator == numerator &&
+		    adc5_prescale_ratios[pre].denominator == denominator)
 			break;
 
 	if (pre == ARRAY_SIZE(adc5_prescale_ratios))
diff --git a/include/linux/iio/adc/qcom-vadc-common.h b/include/linux/iio/adc/qcom-vadc-common.h
index 33f60f43e1aa..ce78d4804994 100644
--- a/include/linux/iio/adc/qcom-vadc-common.h
+++ b/include/linux/iio/adc/qcom-vadc-common.h
@@ -6,6 +6,7 @@
 #ifndef QCOM_VADC_COMMON_H
 #define QCOM_VADC_COMMON_H
 
+#include <linux/math.h>
 #include <linux/types.h>
 
 #define VADC_CONV_TIME_MIN_US			2000
@@ -79,16 +80,6 @@ struct vadc_linear_graph {
 	s32 gnd;
 };
 
-/**
- * struct vadc_prescale_ratio - Represent scaling ratio for ADC input.
- * @num: the inverse numerator of the gain applied to the input channel.
- * @den: the inverse denominator of the gain applied to the input channel.
- */
-struct vadc_prescale_ratio {
-	u32 num;
-	u32 den;
-};
-
 /**
  * enum vadc_scale_fn_type - Scaling function to convert ADC code to
  *				physical scaled units for the channel.
@@ -144,12 +135,12 @@ struct adc5_data {
 
 int qcom_vadc_scale(enum vadc_scale_fn_type scaletype,
 		    const struct vadc_linear_graph *calib_graph,
-		    const struct vadc_prescale_ratio *prescale,
+		    const struct u32_fract *prescale,
 		    bool absolute,
 		    u16 adc_code, int *result_mdec);
 
 struct qcom_adc5_scale_type {
-	int (*scale_fn)(const struct vadc_prescale_ratio *prescale,
+	int (*scale_fn)(const struct u32_fract *prescale,
 		const struct adc5_data *data, u16 adc_code, int *result);
 };
 
-- 
2.34.1

Re: [PATCH v4 1/4] math.h: Introduce data types for fractional numbers

[Andy Shevchenko]

On Wed, Jan 26, 2022 at 03:53:50PM +0200, Andy Shevchenko wrote:
> Introduce a macro to produce data types like
> 
> 	struct TYPE_fract {
> 		__TYPE numerator;
> 		__TYPE denominator;
> 	};
> 
> to be used in the code wherever it's needed.
> 
> In the following changes convert some users to it.

The context of v4 is the dropped AFE patches.

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v4 1/4] math.h: Introduce data types for fractional numbers

[Jonathan Cameron]

On Wed, 26 Jan 2022 15:53:50 +0200
Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote:

> Introduce a macro to produce data types like
> 
> 	struct TYPE_fract {
> 		__TYPE numerator;
> 		__TYPE denominator;
> 	};
> 
> to be used in the code wherever it's needed.
> 
> In the following changes convert some users to it.
> 
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

I'm not 100% sold on this, but I'm going to give them the benefit
of the doubt as to long term usefulness and apply them.

Basically I'm taking the view Andy is often right :)

Applied to the togreg branch of iio.git and pushed out as testing
for 0-day to see if we missed anything.

Thanks,

Jonathan

> ---
> 
> May be pulled via IIO tree.
> 
> v4: no changes
> v3: no changes
> v2: no changes
> 
>  include/linux/math.h | 12 ++++++++++++
>  1 file changed, 12 insertions(+)
> 
> diff --git a/include/linux/math.h b/include/linux/math.h
> index 53674a327e39..439b8f0b9ebd 100644
> --- a/include/linux/math.h
> +++ b/include/linux/math.h
> @@ -2,6 +2,7 @@
>  #ifndef _LINUX_MATH_H
>  #define _LINUX_MATH_H
>  
> +#include <linux/types.h>
>  #include <asm/div64.h>
>  #include <uapi/linux/kernel.h>
>  
> @@ -106,6 +107,17 @@
>  }							\
>  )
>  
> +#define __STRUCT_FRACT(type)				\
> +struct type##_fract {					\
> +	__##type numerator;				\
> +	__##type denominator;				\
> +};
> +__STRUCT_FRACT(s16)
> +__STRUCT_FRACT(u16)
> +__STRUCT_FRACT(s32)
> +__STRUCT_FRACT(u32)
> +#undef __STRUCT_FRACT
> +
>  /*
>   * Multiplies an integer by a fraction, while avoiding unnecessary
>   * overflow or loss of precision.

Re: [PATCH v4 1/4] math.h: Introduce data types for fractional numbers

[Andy Shevchenko]

On Sun, Jan 30, 2022 at 12:30:47PM +0000, Jonathan Cameron wrote:
> On Wed, 26 Jan 2022 15:53:50 +0200
> Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote:
> 
> > Introduce a macro to produce data types like
> > 
> > 	struct TYPE_fract {
> > 		__TYPE numerator;
> > 		__TYPE denominator;
> > 	};
> > 
> > to be used in the code wherever it's needed.
> > 
> > In the following changes convert some users to it.
> > 
> > Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> 
> I'm not 100% sold on this, but I'm going to give them the benefit
> of the doubt as to long term usefulness and apply them.
> 
> Basically I'm taking the view Andy is often right :)

Time will show :-)

> Applied to the togreg branch of iio.git and pushed out as testing
> for 0-day to see if we missed anything.

Thanks!

-- 
With Best Regards,
Andy Shevchenko