[PATCH 0/16] lib: Refactor find_closest() and find_closest_descending() from macros to lib functions

[PATCH 0/16] lib: Refactor find_closest() and find_closest_descending() from macros to lib functions

[Alexandru Soponar]

This patch series converts the find_closest() and find_closest_descending() macros
into proper library functions. The conversion moves these utilities from macro
implementations in util_macros.h to standard C functions in lib/find_closest.c.

The first 15 patches modify individual callers across hwmon, iio, leds, regulator,
and watchdog subsystems to ensure they work correctly with the new function-based
implementation. This maintains compatibility while allowing the final conversion.

The final patch implements the actual refactoring by moving the code to
lib/find_closest.c. This approach was chosen based on discussions between
Andrew Morton and Alexandru Ardelean[1], who suggested that a non-inline
implementation would be appropriate given the size of the functions.

The refactoring avoids of macro expansion-related issues and proper function
prototypes with well-defined parameter types.

Links:
[1] https://lore.kernel.org/lkml/20241105145406.554365-1-aardelean@baylibre.com/

Alexandru Soponar (16):
  hwmon: w83795: Fix type incompatibility with non-macro find_closest
  hwmon: emc1403: Fix type incompatibility with non-macro find_closest
  hwmon: ina3221: Fix type incompatibility with non-macro find_closest
  hwmon: lm95234: Fix type incompatibility with non-macro find_closest
  hwmon: max1619: Fix type incompatibility with non-macro find_closest
  hwmon: lm75: Fix type incompatibility with non-macro find_closest
  hwmon: ltc4282: Fix type incompatibility with non-macro find_closest
  hwmon: max6639: Fix type incompatibility with non-macro find_closest
  hwmon: max20740: Fix type incompatibility with non-macro find_closest
  iio: ad7606: Fix type incompatibility with non-macro find_closest
  iio: mcp3564: Fix type incompatibility with non-macro find_closest
  iio: max44009: Fix type incompatibility with non-macro find_closest
  leds: eds-mt6370-rgb: Fix type incompatibility with find_closest()
  regulator: max77857: Fix type incompatibility with find_closest()
  watchdog: simatic-ipc-wdt: Fix type incompatibility with
    find_closest()
  lib: move find_closest() and find_closest_descending() to lib
    functions

 drivers/hwmon/emc1403.c                |  2 +-
 drivers/hwmon/ina3221.c                |  8 +--
 drivers/hwmon/lm75.c                   | 42 +++++++--------
 drivers/hwmon/lm95234.c                |  2 +-
 drivers/hwmon/ltc4282.c                |  2 +-
 drivers/hwmon/max1619.c                |  2 +-
 drivers/hwmon/max6639.c                |  2 +-
 drivers/hwmon/pmbus/max20730.c         |  4 +-
 drivers/hwmon/w83795.c                 |  2 +-
 drivers/iio/adc/ad7606.c               |  8 +--
 drivers/iio/adc/mcp3564.c              |  2 +-
 drivers/iio/light/max44009.c           |  2 +-
 drivers/leds/rgb/leds-mt6370-rgb.c     |  9 ++--
 drivers/regulator/max77857-regulator.c |  2 +-
 drivers/watchdog/simatic-ipc-wdt.c     |  2 +-
 include/linux/find_closest.h           | 13 +++++
 include/linux/util_macros.h            | 61 +---------------------
 lib/Makefile                           |  2 +-
 lib/find_closest.c                     | 71 ++++++++++++++++++++++++++
 19 files changed, 132 insertions(+), 106 deletions(-)
 create mode 100644 include/linux/find_closest.h
 create mode 100644 lib/find_closest.c

-- 
2.49.0

[PATCH 01/16] hwmon: w83795: Fix type incompatibility with non-macro find_closest

[Alexandru Soponar]

The pwm_freq_cksel0 array was previously declared as u16 but used with
find_closest_descending(). Now that find_closest_descending() is
implemented as a function with 'int' parameters instead of a macro,
passing unsigned arrays causes type incompatibility errors. This patch
changes the array type from u16 to int to match the function's signature
and prevent compilation errors.

Signed-off-by: Alexandru Soponar <asoponar@taladin.ro>
---
 drivers/hwmon/w83795.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/hwmon/w83795.c b/drivers/hwmon/w83795.c
index 5174db69db5e..1b63bd540f6c 100644
--- a/drivers/hwmon/w83795.c
+++ b/drivers/hwmon/w83795.c
@@ -273,7 +273,7 @@ static inline s8 temp_to_reg(long val, s8 min, s8 max)
 	return clamp_val(val / 1000, min, max);
 }
 
-static const u16 pwm_freq_cksel0[16] = {
+static const int pwm_freq_cksel0[16] = {
 	1024, 512, 341, 256, 205, 171, 146, 128,
 	85, 64, 32, 16, 8, 4, 2, 1
 };
-- 
2.49.0

[PATCH 02/16] hwmon: emc1403: Fix type incompatibility with non-macro find_closest

[Alexandru Soponar]

The ina3221_conv_time array was previously declared as u16 but used with
find_closest_descending(). With find_closest_descending() now implemented
as a function taking 'int' parameters instead of a macro, passing unsigned
arrays causes type incompatibility errors. Change the array type from u16
to int to ensure compatibility with the new function signature.

Signed-off-by: Alexandru Soponar <asoponar@taladin.ro>
---
 drivers/hwmon/emc1403.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/hwmon/emc1403.c b/drivers/hwmon/emc1403.c
index eca33220d34a..41590b44b162 100644
--- a/drivers/hwmon/emc1403.c
+++ b/drivers/hwmon/emc1403.c
@@ -517,7 +517,7 @@ static int emc1403_temp_write(struct thermal_data *data, u32 attr, int channel,
 }
 
 /* Lookup table for temperature conversion times in msec */
-static const u16 ina3221_conv_time[] = {
+static const int ina3221_conv_time[] = {
 	16000, 8000, 4000, 2000, 1000, 500, 250, 125, 62, 31, 16
 };
 
-- 
2.49.0

[PATCH 03/16] hwmon: ina3221: Fix type incompatibility with non-macro find_closest

[Alexandru Soponar]

The ina3221_conv_time array was previously declared as u16 but used with
find_closest(). With find_closest() now implemented as a function taking
signed int parameters instead of a macro, passing unsigned arrays causes
type incompatibility errors. This patch changes the array type from
u16 to int to ensure compatibility with the function signature and
prevent compilation errors.

Signed-off-by: Alexandru Soponar <asoponar@taladin.ro>
---
 drivers/hwmon/ina3221.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/hwmon/ina3221.c b/drivers/hwmon/ina3221.c
index 1bf479a0f793..482ab8e53d5c 100644
--- a/drivers/hwmon/ina3221.c
+++ b/drivers/hwmon/ina3221.c
@@ -178,7 +178,7 @@ static inline int ina3221_summation_shunt_resistor(struct ina3221_data *ina)
 }
 
 /* Lookup table for Bus and Shunt conversion times in usec */
-static const u16 ina3221_conv_time[] = {
+static const int ina3221_conv_time[] = {
 	140, 204, 332, 588, 1100, 2116, 4156, 8244,
 };
 
@@ -192,7 +192,7 @@ static inline u32 ina3221_interval_ms_to_conv_time(u16 config, int interval)
 {
 	u32 channels = hweight16(config & INA3221_CONFIG_CHs_EN_MASK);
 	u32 samples_idx = INA3221_CONFIG_AVG(config);
-	u32 samples = ina3221_avg_samples[samples_idx];
+	int samples = ina3221_avg_samples[samples_idx];
 
 	/* Bisect the result to Bus and Shunt conversion times */
 	return DIV_ROUND_CLOSEST(interval * 1000 / 2, channels * samples);
@@ -204,8 +204,8 @@ static inline u32 ina3221_reg_to_interval_us(u16 config)
 	u32 channels = hweight16(config & INA3221_CONFIG_CHs_EN_MASK);
 	u32 vbus_ct_idx = INA3221_CONFIG_VBUS_CT(config);
 	u32 vsh_ct_idx = INA3221_CONFIG_VSH_CT(config);
-	u32 vbus_ct = ina3221_conv_time[vbus_ct_idx];
-	u32 vsh_ct = ina3221_conv_time[vsh_ct_idx];
+	int vbus_ct = ina3221_conv_time[vbus_ct_idx];
+	int vsh_ct = ina3221_conv_time[vsh_ct_idx];
 
 	/* Calculate total conversion time */
 	return channels * (vbus_ct + vsh_ct);
-- 
2.49.0

[PATCH 04/16] hwmon: lm95234: Fix type incompatibility with non-macro find_closest

[Alexandru Soponar]

The update_intervals array was previously declared as u16 but used with
find_closest(). With find_closest() now implemented as a function taking
signed int parameters instead of a macro, passing unsigned arrays causes
type incompatibility errors. This patch changes the array type from
u16 to int to ensure compatibility with the function signature and
prevent compilation errors.

Signed-off-by: Alexandru Soponar <asoponar@taladin.ro>
---
 drivers/hwmon/lm95234.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/hwmon/lm95234.c b/drivers/hwmon/lm95234.c
index 7da6c8f07332..e808fd7d5587 100644
--- a/drivers/hwmon/lm95234.c
+++ b/drivers/hwmon/lm95234.c
@@ -240,7 +240,7 @@ static int lm95234_temp_read(struct device *dev, u32 attr, int channel, long *va
 	return 0;
 }
 
-static u16 update_intervals[] = { 143, 364, 1000, 2500 };
+static int update_intervals[] = { 143, 364, 1000, 2500 };
 
 static int lm95234_chip_write(struct device *dev, u32 attr, long val)
 {
-- 
2.49.0

[PATCH 05/16] hwmon: max1619: Fix type incompatibility with non-macro find_closest

[Alexandru Soponar]

The update_intervals array was previously declared as u16 but used with
find_closest_descending(). With find_closest_descending() now implemented
as a function taking signed int parameters instead of a macro, passing
unsigned arrays causes type incompatibility errors. This patch changes
the array type from u16 to int to ensure compatibility with the function
signature and prevent compilation errors.

Signed-off-by: Alexandru Soponar <asoponar@taladin.ro>
---
 drivers/hwmon/max1619.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/hwmon/max1619.c b/drivers/hwmon/max1619.c
index 9b6d03cff4df..0bd9fbb2517c 100644
--- a/drivers/hwmon/max1619.c
+++ b/drivers/hwmon/max1619.c
@@ -103,7 +103,7 @@ static int max1619_temp_read(struct regmap *regmap, u32 attr, int channel, long
 	return 0;
 }
 
-static u16 update_intervals[] = { 16000, 8000, 4000, 2000, 1000, 500, 250, 125 };
+static int update_intervals[] = { 16000, 8000, 4000, 2000, 1000, 500, 250, 125 };
 
 static int max1619_chip_read(struct regmap *regmap, u32 attr, long *val)
 {
-- 
2.49.0

[PATCH 06/16] hwmon: lm75: Fix type incompatibility with non-macro find_closest

[Alexandru Soponar]

The default_sample_time and sample_times members of lm75_params were
previously declared as unsigned int but used withfind_closest(). With
find_closest() now implemented as a function taking signed int parameters
instead of a macro, passing unsigned arrays causes type incompatibility
errors. This patch changes the types from unsigned int and unsigned int*
to int respectively int* to ensure compatibility with the function
signature and prevent compilation errors.

Signed-off-by: Alexandru Soponar <asoponar@taladin.ro>
---
 drivers/hwmon/lm75.c | 42 +++++++++++++++++++++---------------------
 1 file changed, 21 insertions(+), 21 deletions(-)

diff --git a/drivers/hwmon/lm75.c b/drivers/hwmon/lm75.c
index d95a3c6c245c..5c835ee189d4 100644
--- a/drivers/hwmon/lm75.c
+++ b/drivers/hwmon/lm75.c
@@ -89,9 +89,9 @@ struct lm75_params {
 	u8			default_resolution;
 	u8			resolution_limits;
 	const u8		*resolutions;
-	unsigned int		default_sample_time;
+	int			default_sample_time;
 	u8			num_sample_times;
-	const unsigned int	*sample_times;
+	const int		*sample_times;
 	bool			alarm;
 };
 
@@ -110,7 +110,7 @@ struct lm75_data {
 	struct regmap			*regmap;
 	u16				orig_conf;
 	u8				resolution;	/* In bits, 9 to 16 */
-	unsigned int			sample_time;	/* In ms */
+	int				sample_time;	/* In ms */
 	enum lm75_type			kind;
 	const struct lm75_params	*params;
 	u8				reg_buf[1];
@@ -139,7 +139,7 @@ static const struct lm75_params device_params[] = {
 		.default_resolution = 12,
 		.default_sample_time = 125,
 		.num_sample_times = 4,
-		.sample_times = (unsigned int []){ 125, 250, 1000, 4000 },
+		.sample_times = (int []){ 125, 250, 1000, 4000 },
 		.alarm = true,
 	},
 	[at30ts74] = {
@@ -147,7 +147,7 @@ static const struct lm75_params device_params[] = {
 		.default_resolution = 12,
 		.default_sample_time = 200,
 		.num_sample_times = 4,
-		.sample_times = (unsigned int []){ 25, 50, 100, 200 },
+		.sample_times = (int []){ 25, 50, 100, 200 },
 		.resolutions = (u8 []) {9, 10, 11, 12 },
 	},
 	[ds1775] = {
@@ -156,7 +156,7 @@ static const struct lm75_params device_params[] = {
 		.default_resolution = 11,
 		.default_sample_time = 500,
 		.num_sample_times = 4,
-		.sample_times = (unsigned int []){ 125, 250, 500, 1000 },
+		.sample_times = (int []){ 125, 250, 500, 1000 },
 		.resolutions = (u8 []) {9, 10, 11, 12 },
 	},
 	[ds75] = {
@@ -165,7 +165,7 @@ static const struct lm75_params device_params[] = {
 		.default_resolution = 11,
 		.default_sample_time = 600,
 		.num_sample_times = 4,
-		.sample_times = (unsigned int []){ 150, 300, 600, 1200 },
+		.sample_times = (int []){ 150, 300, 600, 1200 },
 		.resolutions = (u8 []) {9, 10, 11, 12 },
 	},
 	[stds75] = {
@@ -174,7 +174,7 @@ static const struct lm75_params device_params[] = {
 		.default_resolution = 11,
 		.default_sample_time = 600,
 		.num_sample_times = 4,
-		.sample_times = (unsigned int []){ 150, 300, 600, 1200 },
+		.sample_times = (int []){ 150, 300, 600, 1200 },
 		.resolutions = (u8 []) {9, 10, 11, 12 },
 	},
 	[stlm75] = {
@@ -186,7 +186,7 @@ static const struct lm75_params device_params[] = {
 		.default_resolution = 12,
 		.default_sample_time = 200,
 		.num_sample_times = 4,
-		.sample_times = (unsigned int []){ 25, 50, 100, 200 },
+		.sample_times = (int []){ 25, 50, 100, 200 },
 		.resolutions = (u8 []) {9, 10, 11, 12 },
 	},
 	[g751] = {
@@ -227,13 +227,13 @@ static const struct lm75_params device_params[] = {
 		.default_resolution = 12,
 		.default_sample_time = 55,
 		.num_sample_times = 4,
-		.sample_times = (unsigned int []){ 28, 55, 110, 220 },
+		.sample_times = (int []){ 28, 55, 110, 220 },
 	},
 	[pct2075] = {
 		.default_resolution = 11,
 		.default_sample_time = MSEC_PER_SEC / 10,
 		.num_sample_times = 31,
-		.sample_times = (unsigned int []){ 100, 200, 300, 400, 500, 600,
+		.sample_times = (int []){ 100, 200, 300, 400, 500, 600,
 		700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700,
 		1800, 1900, 2000, 2100, 2200, 2300, 2400, 2500, 2600, 2700,
 		2800, 2900, 3000, 3100 },
@@ -245,7 +245,7 @@ static const struct lm75_params device_params[] = {
 		.resolution_limits = 9,
 		.default_sample_time = 240,
 		.num_sample_times = 4,
-		.sample_times = (unsigned int []){ 30, 60, 120, 240 },
+		.sample_times = (int []){ 30, 60, 120, 240 },
 		.resolutions = (u8 []) {9, 10, 11, 12 },
 	},
 	[tmp100] = {
@@ -254,7 +254,7 @@ static const struct lm75_params device_params[] = {
 		.default_resolution = 12,
 		.default_sample_time = 320,
 		.num_sample_times = 4,
-		.sample_times = (unsigned int []){ 40, 80, 160, 320 },
+		.sample_times = (int []){ 40, 80, 160, 320 },
 		.resolutions = (u8 []) {9, 10, 11, 12 },
 	},
 	[tmp101] = {
@@ -263,7 +263,7 @@ static const struct lm75_params device_params[] = {
 		.default_resolution = 12,
 		.default_sample_time = 320,
 		.num_sample_times = 4,
-		.sample_times = (unsigned int []){ 40, 80, 160, 320 },
+		.sample_times = (int []){ 40, 80, 160, 320 },
 		.resolutions = (u8 []) {9, 10, 11, 12 },
 	},
 	[tmp105] = {
@@ -272,7 +272,7 @@ static const struct lm75_params device_params[] = {
 		.default_resolution = 12,
 		.default_sample_time = 220,
 		.num_sample_times = 4,
-		.sample_times = (unsigned int []){ 28, 55, 110, 220 },
+		.sample_times = (int []){ 28, 55, 110, 220 },
 		.resolutions = (u8 []) {9, 10, 11, 12 },
 	},
 	[tmp112] = {
@@ -282,7 +282,7 @@ static const struct lm75_params device_params[] = {
 		.default_resolution = 12,
 		.default_sample_time = 125,
 		.num_sample_times = 4,
-		.sample_times = (unsigned int []){ 125, 250, 1000, 4000 },
+		.sample_times = (int []){ 125, 250, 1000, 4000 },
 		.alarm = true,
 	},
 	[tmp175] = {
@@ -291,7 +291,7 @@ static const struct lm75_params device_params[] = {
 		.default_resolution = 12,
 		.default_sample_time = 220,
 		.num_sample_times = 4,
-		.sample_times = (unsigned int []){ 28, 55, 110, 220 },
+		.sample_times = (int []){ 28, 55, 110, 220 },
 		.resolutions = (u8 []) {9, 10, 11, 12 },
 	},
 	[tmp275] = {
@@ -300,7 +300,7 @@ static const struct lm75_params device_params[] = {
 		.default_resolution = 12,
 		.default_sample_time = 220,
 		.num_sample_times = 4,
-		.sample_times = (unsigned int []){ 28, 55, 110, 220 },
+		.sample_times = (int []){ 28, 55, 110, 220 },
 		.resolutions = (u8 []) {9, 10, 11, 12 },
 	},
 	[tmp75] = {
@@ -309,14 +309,14 @@ static const struct lm75_params device_params[] = {
 		.default_resolution = 12,
 		.default_sample_time = 220,
 		.num_sample_times = 4,
-		.sample_times = (unsigned int []){ 28, 55, 110, 220 },
+		.sample_times = (int []){ 28, 55, 110, 220 },
 		.resolutions = (u8 []) {9, 10, 11, 12 },
 	},
 	[tmp75b] = { /* not one-shot mode, Conversion rate 37Hz */
 		.clr_mask = 1 << 7 | 3 << 5,
 		.default_resolution = 12,
 		.default_sample_time = MSEC_PER_SEC / 37,
-		.sample_times = (unsigned int []){ MSEC_PER_SEC / 37,
+		.sample_times = (int []){ MSEC_PER_SEC / 37,
 			MSEC_PER_SEC / 18,
 			MSEC_PER_SEC / 9, MSEC_PER_SEC / 4 },
 		.num_sample_times = 4,
@@ -331,7 +331,7 @@ static const struct lm75_params device_params[] = {
 		.default_resolution = 12,
 		.default_sample_time = 28,
 		.num_sample_times = 4,
-		.sample_times = (unsigned int []){ 28, 55, 110, 220 },
+		.sample_times = (int []){ 28, 55, 110, 220 },
 	}
 };
 
-- 
2.49.0

[PATCH 07/16] hwmon: ltc4282: Fix type incompatibility with non-macro find_closest

[Alexandru Soponar]

The ltc4282_out_rates array was previously declared as unsigned int but
used with find_closest(). With find_closest() now implemented as a function
taking signed int parameters instead of a macro, passing unsigned arrays
causes type incompatibility errors. This patch changes the array type from
unsigned int to int to ensure compatibility with the function signature and
prevent compilation errors.

Signed-off-by: Alexandru Soponar <asoponar@taladin.ro>
---
 drivers/hwmon/ltc4282.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/hwmon/ltc4282.c b/drivers/hwmon/ltc4282.c
index 4f608a3790fb..1908a998feb1 100644
--- a/drivers/hwmon/ltc4282.c
+++ b/drivers/hwmon/ltc4282.c
@@ -173,7 +173,7 @@ static int ltc4282_set_rate(struct clk_hw *hw,
  * Note the 15HZ conversion rate assumes 12bit ADC which is what we are
  * supporting for now.
  */
-static const unsigned int ltc4282_out_rates[] = {
+static const int ltc4282_out_rates[] = {
 	LTC4282_CLKOUT_CNV, LTC4282_CLKOUT_SYSTEM
 };
 
-- 
2.49.0

[PATCH 08/16] hwmon: max6639: Fix type incompatibility with non-macro find_closest

[Alexandru Soponar]

The freq_table array was previously declared as unsigned int but used
with find_closest(). With find_closest() now implemented as a function
taking signed int parameters instead of a macro, passing unsigned arrays
causes type incompatibility errors. This patch changes the array type from
unsigned int to int to ensure compatibility with the function signature and
prevent compilation errors.

Signed-off-by: Alexandru Soponar <asoponar@taladin.ro>
---
 drivers/hwmon/max6639.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/hwmon/max6639.c b/drivers/hwmon/max6639.c
index 32b4d54b2076..b6942b406880 100644
--- a/drivers/hwmon/max6639.c
+++ b/drivers/hwmon/max6639.c
@@ -63,7 +63,7 @@ static const unsigned short normal_i2c[] = { 0x2c, 0x2e, 0x2f, I2C_CLIENT_END };
 static const int rpm_ranges[] = { 2000, 4000, 8000, 16000 };
 
 /* Supported PWM frequency */
-static const unsigned int freq_table[] = { 20, 33, 50, 100, 5000, 8333, 12500,
+static const int freq_table[] = { 20, 33, 50, 100, 5000, 8333, 12500,
 					   25000 };
 
 #define FAN_FROM_REG(val, rpm_range)	((val) == 0 || (val) == 255 ? \
-- 
2.49.0

[PATCH 09/16] hwmon: max20740: Fix type incompatibility with non-macro find_closest

[Alexandru Soponar]

The max_current array was previously declared as u32 but used with
find_closest(). With find_closest() now implemented as a function taking
signed int parameters instead of a macro, passing unsigned arrays causes
type incompatibility errors. This patch changes the array type from u32
to int to ensure compatibility with the function signature and prevent
compilation errors.

Signed-off-by: Alexandru Soponar <asoponar@taladin.ro>
---
 drivers/hwmon/pmbus/max20730.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/hwmon/pmbus/max20730.c b/drivers/hwmon/pmbus/max20730.c
index 95869d198ecf..0e8d292e9ff4 100644
--- a/drivers/hwmon/pmbus/max20730.c
+++ b/drivers/hwmon/pmbus/max20730.c
@@ -436,7 +436,7 @@ static long direct_to_val(u16 w, enum pmbus_sensor_classes class,
 	return d;
 }
 
-static u32 max_current[][5] = {
+static int max_current[][5] = {
 	[max20710] = { 6200, 8000, 9700, 11600 },
 	[max20730] = { 13000, 16600, 20100, 23600 },
 	[max20734] = { 21000, 27000, 32000, 38000 },
@@ -449,7 +449,7 @@ static int max20730_read_word_data(struct i2c_client *client, int page,
 	const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
 	const struct max20730_data *data = to_max20730_data(info);
 	int ret = 0;
-	u32 max_c;
+	int max_c;
 
 	switch (reg) {
 	case PMBUS_OT_FAULT_LIMIT:
-- 
2.49.0

[PATCH 10/16] iio: ad7606: Fix type incompatibility with non-macro find_closest

[Alexandru Soponar]

The ad7606_oversampling_avail and ad7616_oversampling_avail arrays were
previously declared as unsigned int but used with find_closest(). With
find_closest() now implemented as a function taking signed int parameters
instead of a macro, passing unsigned arrays causes type incompatibility
errors. This patch changes the arrays type from unsigned int to int to
ensure compatibility with the function signature and prevent compilation
errors.

Signed-off-by: Alexandru Soponar <asoponar@taladin.ro>
---
 drivers/iio/adc/ad7606.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/iio/adc/ad7606.c b/drivers/iio/adc/ad7606.c
index d8e3c7a43678..41b477ea386d 100644
--- a/drivers/iio/adc/ad7606.c
+++ b/drivers/iio/adc/ad7606.c
@@ -81,11 +81,11 @@ static const unsigned int ad7609_hw_scale_avail[2][2] = {
 	{ 0, 152588 }, { 0, 305176 }
 };
 
-static const unsigned int ad7606_oversampling_avail[7] = {
+static const int ad7606_oversampling_avail[7] = {
 	1, 2, 4, 8, 16, 32, 64,
 };
 
-static const unsigned int ad7616_oversampling_avail[8] = {
+static const int ad7616_oversampling_avail[8] = {
 	1, 2, 4, 8, 16, 32, 64, 128,
 };
 
@@ -835,7 +835,7 @@ static int ad7606_write_raw(struct iio_dev *indio_dev,
 			    long mask)
 {
 	struct ad7606_state *st = iio_priv(indio_dev);
-	unsigned int scale_avail_uv[AD760X_MAX_SCALES];
+	int scale_avail_uv[AD760X_MAX_SCALES];
 	struct ad7606_chan_scale *cs;
 	int i, ret, ch = 0;
 
@@ -884,7 +884,7 @@ static ssize_t ad7606_oversampling_ratio_avail(struct device *dev,
 {
 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 	struct ad7606_state *st = iio_priv(indio_dev);
-	const unsigned int *vals = st->oversampling_avail;
+	const int *vals = st->oversampling_avail;
 	unsigned int i;
 	size_t len = 0;
 
-- 
2.49.0

Re: [PATCH 10/16] iio: ad7606: Fix type incompatibility with non-macro find_closest

[Jonathan Cameron]

On Thu, 15 May 2025 11:13:26 +0300
Alexandru Soponar <asoponar@taladin.ro> wrote:

> The ad7606_oversampling_avail and ad7616_oversampling_avail arrays were
> previously declared as unsigned int but used with find_closest(). With
> find_closest() now implemented as a function taking signed int parameters
> instead of a macro, passing unsigned arrays causes type incompatibility
> errors. This patch changes the arrays type from unsigned int to int to
> ensure compatibility with the function signature and prevent compilation
> errors.
> 
> Signed-off-by: Alexandru Soponar <asoponar@taladin.ro>
Assuming overall approach is fine, this change is fine wrt to ranges
etc.

Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

> ---
>  drivers/iio/adc/ad7606.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/iio/adc/ad7606.c b/drivers/iio/adc/ad7606.c
> index d8e3c7a43678..41b477ea386d 100644
> --- a/drivers/iio/adc/ad7606.c
> +++ b/drivers/iio/adc/ad7606.c
> @@ -81,11 +81,11 @@ static const unsigned int ad7609_hw_scale_avail[2][2] = {
>  	{ 0, 152588 }, { 0, 305176 }
>  };
>  
> -static const unsigned int ad7606_oversampling_avail[7] = {
> +static const int ad7606_oversampling_avail[7] = {
>  	1, 2, 4, 8, 16, 32, 64,
>  };
>  
> -static const unsigned int ad7616_oversampling_avail[8] = {
> +static const int ad7616_oversampling_avail[8] = {
>  	1, 2, 4, 8, 16, 32, 64, 128,
>  };
>  
> @@ -835,7 +835,7 @@ static int ad7606_write_raw(struct iio_dev *indio_dev,
>  			    long mask)
>  {
>  	struct ad7606_state *st = iio_priv(indio_dev);
> -	unsigned int scale_avail_uv[AD760X_MAX_SCALES];
> +	int scale_avail_uv[AD760X_MAX_SCALES];
>  	struct ad7606_chan_scale *cs;
>  	int i, ret, ch = 0;
>  
> @@ -884,7 +884,7 @@ static ssize_t ad7606_oversampling_ratio_avail(struct device *dev,
>  {
>  	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
>  	struct ad7606_state *st = iio_priv(indio_dev);
> -	const unsigned int *vals = st->oversampling_avail;
> +	const int *vals = st->oversampling_avail;
>  	unsigned int i;
>  	size_t len = 0;
>  

[PATCH 11/16] iio: mcp3564: Fix type incompatibility with non-macro find_closest

[Alexandru Soponar]

The mcp3564_oversampling_avail array was previously declared as unsigned
int but used with find_closest(). With find_closest() now implemented as
a function taking signed int parameters instead of a macro,  passing
unsigned arrays causes type incompatibility errors. This patch changes the
arrays type from unsigned int to int to ensure compatibility with the
function signature and prevent compilation errors.

Signed-off-by: Alexandru Soponar <asoponar@taladin.ro>
---
 drivers/iio/adc/mcp3564.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iio/adc/mcp3564.c b/drivers/iio/adc/mcp3564.c
index a68f1cd6883e..01efc77f710a 100644
--- a/drivers/iio/adc/mcp3564.c
+++ b/drivers/iio/adc/mcp3564.c
@@ -253,7 +253,7 @@ enum mcp3564_oversampling {
 	MCP3564_OVERSAMPLING_RATIO_98304
 };
 
-static const unsigned int mcp3564_oversampling_avail[] = {
+static const int mcp3564_oversampling_avail[] = {
 	[MCP3564_OVERSAMPLING_RATIO_32] = 32,
 	[MCP3564_OVERSAMPLING_RATIO_64] = 64,
 	[MCP3564_OVERSAMPLING_RATIO_128] = 128,
-- 
2.49.0

Re: [PATCH 11/16] iio: mcp3564: Fix type incompatibility with non-macro find_closest

[Jonathan Cameron]

On Thu, 15 May 2025 11:13:27 +0300
Alexandru Soponar <asoponar@taladin.ro> wrote:

> The mcp3564_oversampling_avail array was previously declared as unsigned
> int but used with find_closest(). With find_closest() now implemented as
> a function taking signed int parameters instead of a macro,  passing
> unsigned arrays causes type incompatibility errors. This patch changes the
> arrays type from unsigned int to int to ensure compatibility with the
> function signature and prevent compilation errors.
> 
> Signed-off-by: Alexandru Soponar <asoponar@taladin.ro>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> ---
>  drivers/iio/adc/mcp3564.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/iio/adc/mcp3564.c b/drivers/iio/adc/mcp3564.c
> index a68f1cd6883e..01efc77f710a 100644
> --- a/drivers/iio/adc/mcp3564.c
> +++ b/drivers/iio/adc/mcp3564.c
> @@ -253,7 +253,7 @@ enum mcp3564_oversampling {
>  	MCP3564_OVERSAMPLING_RATIO_98304
>  };
>  
> -static const unsigned int mcp3564_oversampling_avail[] = {
> +static const int mcp3564_oversampling_avail[] = {
>  	[MCP3564_OVERSAMPLING_RATIO_32] = 32,
>  	[MCP3564_OVERSAMPLING_RATIO_64] = 64,
>  	[MCP3564_OVERSAMPLING_RATIO_128] = 128,

Re: [PATCH 11/16] iio: mcp3564: Fix type incompatibility with non-macro find_closest

[Marius.Cristea]

On Thu, 2025-05-15 at 11:13 +0300, Alexandru Soponar wrote:
> EXTERNAL EMAIL: Do not click links or open attachments unless you
> know the content is safe
> 
> The mcp3564_oversampling_avail array was previously declared as
> unsigned
> int but used with find_closest(). With find_closest() now implemented
> as
> a function taking signed int parameters instead of a macro,  passing
> unsigned arrays causes type incompatibility errors. This patch
> changes the
> arrays type from unsigned int to int to ensure compatibility with the
> function signature and prevent compilation errors.
> 
> Signed-off-by: Alexandru Soponar <asoponar@taladin.ro>

Hi Alexandru,

	Thank you very much for the patch. The patch is OK.

Reviewed-by: Marius Cristea <marius.cristea@microchip.com>


Thanks,
Marius 


> ---
>  drivers/iio/adc/mcp3564.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/iio/adc/mcp3564.c b/drivers/iio/adc/mcp3564.c
> index a68f1cd6883e..01efc77f710a 100644
> --- a/drivers/iio/adc/mcp3564.c
> +++ b/drivers/iio/adc/mcp3564.c
> @@ -253,7 +253,7 @@ enum mcp3564_oversampling {
>         MCP3564_OVERSAMPLING_RATIO_98304
>  };
> 
> -static const unsigned int mcp3564_oversampling_avail[] = {
> +static const int mcp3564_oversampling_avail[] = {
>         [MCP3564_OVERSAMPLING_RATIO_32] = 32,
>         [MCP3564_OVERSAMPLING_RATIO_64] = 64,
>         [MCP3564_OVERSAMPLING_RATIO_128] = 128,
> --
> 2.49.0
> 

[PATCH 12/16] iio: max44009: Fix type incompatibility with non-macro find_closest

[Alexandru Soponar]

The max44009_int_time_ns_array array was previously declared as u32 but
used with find_closest(). With find_closest() now implemented as a
function taking signed int parameters instead of a macro, passing unsigned
arrays causes type incompatibility errors. This patch changes the arrays
type from u32 to int to ensure compatibility with the function signature
and prevent compilation errors.

Signed-off-by: Alexandru Soponar <asoponar@taladin.ro>
---
 drivers/iio/light/max44009.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iio/light/max44009.c b/drivers/iio/light/max44009.c
index 8cd7f5664e5b..d274224fc210 100644
--- a/drivers/iio/light/max44009.c
+++ b/drivers/iio/light/max44009.c
@@ -55,7 +55,7 @@
 /* The fixed-point fractional multiplier for de-scaling threshold values */
 #define MAX44009_FRACT_MULT 1000000
 
-static const u32 max44009_int_time_ns_array[] = {
+static const int max44009_int_time_ns_array[] = {
 	800000000,
 	400000000,
 	200000000,
-- 
2.49.0

Re: [PATCH 12/16] iio: max44009: Fix type incompatibility with non-macro find_closest

[Jonathan Cameron]

On Thu, 15 May 2025 11:13:28 +0300
Alexandru Soponar <asoponar@taladin.ro> wrote:

> The max44009_int_time_ns_array array was previously declared as u32 but
> used with find_closest(). With find_closest() now implemented as a
> function taking signed int parameters instead of a macro, passing unsigned
> arrays causes type incompatibility errors. This patch changes the arrays
> type from u32 to int to ensure compatibility with the function signature
> and prevent compilation errors.
> 
> Signed-off-by: Alexandru Soponar <asoponar@taladin.ro>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> ---
>  drivers/iio/light/max44009.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/iio/light/max44009.c b/drivers/iio/light/max44009.c
> index 8cd7f5664e5b..d274224fc210 100644
> --- a/drivers/iio/light/max44009.c
> +++ b/drivers/iio/light/max44009.c
> @@ -55,7 +55,7 @@
>  /* The fixed-point fractional multiplier for de-scaling threshold values */
>  #define MAX44009_FRACT_MULT 1000000
>  
> -static const u32 max44009_int_time_ns_array[] = {
> +static const int max44009_int_time_ns_array[] = {
>  	800000000,
>  	400000000,
>  	200000000,

[PATCH 13/16] leds: eds-mt6370-rgb: Fix type incompatibility with find_closest()

[Alexandru Soponar]

The common_tfreqs and mt6372_tfreqs arrays were previously declared as
unsigned int but used with find_closest(), which now takes signed int
parameters. Change these arrays from unsigned int to int to maintain type
compatibility with the find_closest() function signature and prevent
compilation errors.

Signed-off-by: Alexandru Soponar <asoponar@taladin.ro>
---
 drivers/leds/rgb/leds-mt6370-rgb.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/leds/rgb/leds-mt6370-rgb.c b/drivers/leds/rgb/leds-mt6370-rgb.c
index ebd3ba878dd5..6ce11432dd96 100644
--- a/drivers/leds/rgb/leds-mt6370-rgb.c
+++ b/drivers/leds/rgb/leds-mt6370-rgb.c
@@ -135,7 +135,7 @@ struct mt6370_led {
 };
 
 struct mt6370_pdata {
-	const unsigned int *tfreq;
+	const int *tfreq;
 	unsigned int tfreq_len;
 	u16 reg_rgb1_tr;
 	s16 reg_rgb_chrind_tr;
@@ -212,11 +212,11 @@ static const struct linear_range mt6372_led_ranges[R_MAX_RANGES] = {
 	[R_LED_TOFF]	= { 250, 0, 15, 500 },
 };
 
-static const unsigned int common_tfreqs[] = {
+static const int common_tfreqs[] = {
 	10000, 5000, 2000, 1000, 500, 200, 5, 1,
 };
 
-static const unsigned int mt6372_tfreqs[] = {
+static const int mt6372_tfreqs[] = {
 	8000, 4000, 2000, 1000, 500, 250, 8, 4,
 };
 
@@ -304,7 +304,8 @@ static int mt6370_set_led_freq(struct mt6370_priv *priv, unsigned int led_no, un
 	const struct mt6370_pdata *pdata = priv->pdata;
 	enum mt6370_led_field sel_field;
 	unsigned int tfreq_len = pdata->tfreq_len;
-	unsigned int tsum, sel;
+	unsigned int sel;
+	int tsum;
 
 	tsum = ton + toff;
 
-- 
2.49.0

Re: [PATCH 13/16] leds: eds-mt6370-rgb: Fix type incompatibility with find_closest()

[Lee Jones]

On Thu, 15 May 2025, Alexandru Soponar wrote:

> The common_tfreqs and mt6372_tfreqs arrays were previously declared as
> unsigned int but used with find_closest(), which now takes signed int
> parameters. Change these arrays from unsigned int to int to maintain type
> compatibility with the find_closest() function signature and prevent
> compilation errors.
> 
> Signed-off-by: Alexandru Soponar <asoponar@taladin.ro>
> ---
>  drivers/leds/rgb/leds-mt6370-rgb.c | 9 +++++----
>  1 file changed, 5 insertions(+), 4 deletions(-)

Acked-by: Lee Jones <lee@kernel.org>

> diff --git a/drivers/leds/rgb/leds-mt6370-rgb.c b/drivers/leds/rgb/leds-mt6370-rgb.c
> index ebd3ba878dd5..6ce11432dd96 100644
> --- a/drivers/leds/rgb/leds-mt6370-rgb.c
> +++ b/drivers/leds/rgb/leds-mt6370-rgb.c
> @@ -135,7 +135,7 @@ struct mt6370_led {
>  };
>  
>  struct mt6370_pdata {
> -	const unsigned int *tfreq;
> +	const int *tfreq;
>  	unsigned int tfreq_len;
>  	u16 reg_rgb1_tr;
>  	s16 reg_rgb_chrind_tr;
> @@ -212,11 +212,11 @@ static const struct linear_range mt6372_led_ranges[R_MAX_RANGES] = {
>  	[R_LED_TOFF]	= { 250, 0, 15, 500 },
>  };
>  
> -static const unsigned int common_tfreqs[] = {
> +static const int common_tfreqs[] = {
>  	10000, 5000, 2000, 1000, 500, 200, 5, 1,
>  };
>  
> -static const unsigned int mt6372_tfreqs[] = {
> +static const int mt6372_tfreqs[] = {
>  	8000, 4000, 2000, 1000, 500, 250, 8, 4,
>  };
>  
> @@ -304,7 +304,8 @@ static int mt6370_set_led_freq(struct mt6370_priv *priv, unsigned int led_no, un
>  	const struct mt6370_pdata *pdata = priv->pdata;
>  	enum mt6370_led_field sel_field;
>  	unsigned int tfreq_len = pdata->tfreq_len;
> -	unsigned int tsum, sel;
> +	unsigned int sel;
> +	int tsum;
>  
>  	tsum = ton + toff;
>  
> -- 
> 2.49.0
> 

-- 
Lee Jones [李琼斯]

[PATCH 14/16] regulator: max77857: Fix type incompatibility with find_closest()

[Alexandru Soponar]

The max77857_switch_freq array was previously declared as unsigned int
but used with find_closest(), which takes signed int parameters. Change
this array from unsigned int to int to maintain type compatibility with
the find_closest() function signature and prevent compilation errors.

Signed-off-by: Alexandru Soponar <asoponar@taladin.ro>
---
 drivers/regulator/max77857-regulator.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/regulator/max77857-regulator.c b/drivers/regulator/max77857-regulator.c
index 1216cc3a6f72..5e64f5510601 100644
--- a/drivers/regulator/max77857-regulator.c
+++ b/drivers/regulator/max77857-regulator.c
@@ -289,7 +289,7 @@ static struct linear_range max77857_lin_ranges[] = {
 	REGULATOR_LINEAR_RANGE(4485000, 0x3D, 0xCC, 73500)
 };
 
-static const unsigned int max77857_switch_freq[] = {
+static const int max77857_switch_freq[] = {
 	1200000, 1500000, 1800000, 2100000
 };
 
-- 
2.49.0

[PATCH 15/16] watchdog: simatic-ipc-wdt: Fix type incompatibility with find_closest()

[Alexandru Soponar]

The wd_timeout_table array was previously declared as unsigned int
but used with find_closest(), which takes signed int parameters. Change
this array from unsigned int to int to maintain type compatibility with
the find_closest() function signature and prevent compilation errors.

Signed-off-by: Alexandru Soponar <asoponar@taladin.ro>
---
 drivers/watchdog/simatic-ipc-wdt.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/watchdog/simatic-ipc-wdt.c b/drivers/watchdog/simatic-ipc-wdt.c
index 1e91f0a560ff..36c68d2ed409 100644
--- a/drivers/watchdog/simatic-ipc-wdt.c
+++ b/drivers/watchdog/simatic-ipc-wdt.c
@@ -59,7 +59,7 @@ static struct resource io_resource_trigger =
 static struct resource mem_resource =
 	DEFINE_RES_MEM_NAMED(0, 0, "WD_RESET_BASE_ADR");
 
-static u32 wd_timeout_table[] = {2, 4, 6, 8, 16, 32, 48, 64 };
+static int wd_timeout_table[] = {2, 4, 6, 8, 16, 32, 48, 64 };
 static void __iomem *wd_reset_base_addr;
 
 static int wd_start(struct watchdog_device *wdd)
-- 
2.49.0

[PATCH 16/16] lib: move find_closest() and find_closest_descending() to lib functions

[Alexandru Soponar]

Move the utility macros find_closest() and find_closest_descending()
from inline macros to proper library functions in lib/.

Signed-off-by: Alexandru Soponar <asoponar@taladin.ro>
---
 include/linux/find_closest.h | 13 +++++++
 include/linux/util_macros.h  | 61 +------------------------------
 lib/Makefile                 |  2 +-
 lib/find_closest.c           | 71 ++++++++++++++++++++++++++++++++++++
 4 files changed, 86 insertions(+), 61 deletions(-)
 create mode 100644 include/linux/find_closest.h
 create mode 100644 lib/find_closest.c

diff --git a/include/linux/find_closest.h b/include/linux/find_closest.h
new file mode 100644
index 000000000000..28a5c4d0c768
--- /dev/null
+++ b/include/linux/find_closest.h
@@ -0,0 +1,13 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Find closest element functions
+ */
+#ifndef _LINUX_FIND_CLOSEST_H_
+#define _LINUX_FIND_CLOSEST_H_
+
+#include <linux/types.h>
+
+unsigned int find_closest(int x, const int *a, unsigned int as);
+unsigned int find_closest_descending(int x, const int *a, unsigned int as);
+
+#endif /* _LINUX_FIND_CLOSEST_H_ */
diff --git a/include/linux/util_macros.h b/include/linux/util_macros.h
index 825487fb66fa..478d4821f2d1 100644
--- a/include/linux/util_macros.h
+++ b/include/linux/util_macros.h
@@ -3,66 +3,7 @@
 #define _LINUX_HELPER_MACROS_H_
 
 #include <linux/math.h>
-
-/**
- * find_closest - locate the closest element in a sorted array
- * @x: The reference value.
- * @a: The array in which to look for the closest element. Must be sorted
- *  in ascending order.
- * @as: Size of 'a'.
- *
- * Returns the index of the element closest to 'x'.
- * Note: If using an array of negative numbers (or mixed positive numbers),
- *       then be sure that 'x' is of a signed-type to get good results.
- */
-#define find_closest(x, a, as)						\
-({									\
-	typeof(as) __fc_i, __fc_as = (as) - 1;				\
-	long __fc_mid_x, __fc_x = (x);					\
-	long __fc_left, __fc_right;					\
-	typeof(*a) const *__fc_a = (a);					\
-	for (__fc_i = 0; __fc_i < __fc_as; __fc_i++) {			\
-		__fc_mid_x = (__fc_a[__fc_i] + __fc_a[__fc_i + 1]) / 2;	\
-		if (__fc_x <= __fc_mid_x) {				\
-			__fc_left = __fc_x - __fc_a[__fc_i];		\
-			__fc_right = __fc_a[__fc_i + 1] - __fc_x;	\
-			if (__fc_right < __fc_left)			\
-				__fc_i++;				\
-			break;						\
-		}							\
-	}								\
-	(__fc_i);							\
-})
-
-/**
- * find_closest_descending - locate the closest element in a sorted array
- * @x: The reference value.
- * @a: The array in which to look for the closest element. Must be sorted
- *  in descending order.
- * @as: Size of 'a'.
- *
- * Similar to find_closest() but 'a' is expected to be sorted in descending
- * order. The iteration is done in reverse order, so that the comparison
- * of '__fc_right' & '__fc_left' also works for unsigned numbers.
- */
-#define find_closest_descending(x, a, as)				\
-({									\
-	typeof(as) __fc_i, __fc_as = (as) - 1;				\
-	long __fc_mid_x, __fc_x = (x);					\
-	long __fc_left, __fc_right;					\
-	typeof(*a) const *__fc_a = (a);					\
-	for (__fc_i = __fc_as; __fc_i >= 1; __fc_i--) {			\
-		__fc_mid_x = (__fc_a[__fc_i] + __fc_a[__fc_i - 1]) / 2;	\
-		if (__fc_x <= __fc_mid_x) {				\
-			__fc_left = __fc_x - __fc_a[__fc_i];		\
-			__fc_right = __fc_a[__fc_i - 1] - __fc_x;	\
-			if (__fc_right < __fc_left)			\
-				__fc_i--;				\
-			break;						\
-		}							\
-	}								\
-	(__fc_i);							\
-})
+#include <linux/find_closest.h>
 
 /**
  * is_insidevar - check if the @ptr points inside the @var memory range.
diff --git a/lib/Makefile b/lib/Makefile
index f1c6e9d76a7c..e8e738c9ced8 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -35,7 +35,7 @@ lib-y := ctype.o string.o vsprintf.o cmdline.o \
 	 is_single_threaded.o plist.o decompress.o kobject_uevent.o \
 	 earlycpio.o seq_buf.o siphash.o dec_and_lock.o \
 	 nmi_backtrace.o win_minmax.o memcat_p.o \
-	 buildid.o objpool.o iomem_copy.o
+	 buildid.o objpool.o iomem_copy.o find_closest.o
 
 lib-$(CONFIG_UNION_FIND) += union_find.o
 lib-$(CONFIG_PRINTK) += dump_stack.o
diff --git a/lib/find_closest.c b/lib/find_closest.c
new file mode 100644
index 000000000000..d481625cae9d
--- /dev/null
+++ b/lib/find_closest.c
@@ -0,0 +1,71 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Find closest element functions
+ *
+ * Based on previous util_macros.h implementation
+ */
+
+#include <linux/find_closest.h>
+#include <linux/module.h>
+
+/**
+ * find_closest - locate the closest element in a sorted array
+ * @x: The reference value.
+ * @a: The array in which to look for the closest element. Must be sorted
+ *  in ascending order.
+ * @as: Size of 'a'.
+ *
+ * Returns the index of the element closest to 'x'.
+ */
+unsigned int find_closest(int x, const int *a, unsigned int as)
+{
+	unsigned int array_size = as - 1;
+	int mid_x, left, right;
+	unsigned int i;
+
+	for (i = 0; i < array_size; i++) {
+		mid_x = (a[i] + a[i + 1]) / 2;
+		if (x <= mid_x) {
+			left = x - a[i];
+			right = a[i + 1] - x;
+			if (right < left)
+				i++;
+			break;
+		}
+	}
+
+	return i;
+}
+EXPORT_SYMBOL_GPL(find_closest);
+
+/**
+ * find_closest_descending - locate the closest element in a sorted array
+ * @x: The reference value.
+ * @a: The array in which to look for the closest element. Must be sorted
+ *  in descending order.
+ * @as: Size of 'a'.
+ *
+ * Similar to find_closest() but 'a' is expected to be sorted in descending
+ * order. The iteration is done in reverse order, so that the comparison
+ * of 'right' & 'left' also works for unsigned numbers.
+ */
+unsigned int find_closest_descending(int x, const int *a, unsigned int as)
+{
+	unsigned int array_size = as - 1;
+	int mid_x, left, right;
+	unsigned int i;
+
+	for (i = array_size; i >= 1; i--) {
+		mid_x = (a[i] + a[i - 1]) / 2;
+		if (x <= mid_x) {
+			left = x - a[i];
+			right = a[i - 1] - x;
+			if (right < left)
+				i--;
+			break;
+		}
+	}
+
+	return i;
+}
+EXPORT_SYMBOL_GPL(find_closest_descending);
-- 
2.49.0

Re: [PATCH 16/16] lib: move find_closest() and find_closest_descending() to lib functions

[David Lechner]

On 5/15/25 3:13 AM, Alexandru Soponar wrote:
> Move the utility macros find_closest() and find_closest_descending()
> from inline macros to proper library functions in lib/.
> 
> Signed-off-by: Alexandru Soponar <asoponar@taladin.ro>
> ---
>  include/linux/find_closest.h | 13 +++++++
>  include/linux/util_macros.h  | 61 +------------------------------
>  lib/Makefile                 |  2 +-
>  lib/find_closest.c           | 71 ++++++++++++++++++++++++++++++++++++
>  4 files changed, 86 insertions(+), 61 deletions(-)
>  create mode 100644 include/linux/find_closest.h
>  create mode 100644 lib/find_closest.c
> 
> diff --git a/include/linux/find_closest.h b/include/linux/find_closest.h
> new file mode 100644
> index 000000000000..28a5c4d0c768
> --- /dev/null
> +++ b/include/linux/find_closest.h
> @@ -0,0 +1,13 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Find closest element functions
> + */
> +#ifndef _LINUX_FIND_CLOSEST_H_
> +#define _LINUX_FIND_CLOSEST_H_
> +
> +#include <linux/types.h>

Is this header really needed?

> +
> +unsigned int find_closest(int x, const int *a, unsigned int as);
> +unsigned int find_closest_descending(int x, const int *a, unsigned int as);
> +
> +#endif /* _LINUX_FIND_CLOSEST_H_ */

...

> diff --git a/lib/find_closest.c b/lib/find_closest.c
> new file mode 100644
> index 000000000000..d481625cae9d
> --- /dev/null
> +++ b/lib/find_closest.c
> @@ -0,0 +1,71 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Find closest element functions
> + *
> + * Based on previous util_macros.h implementation
> + */
> +
> +#include <linux/find_closest.h>
> +#include <linux/module.h>
> +
> +/**
> + * find_closest - locate the closest element in a sorted array
> + * @x: The reference value.
> + * @a: The array in which to look for the closest element. Must be sorted
> + *  in ascending order.
> + * @as: Size of 'a'.
> + *
> + * Returns the index of the element closest to 'x'.

s/Returns/Returns:/

for kernel-doc semantics

> + */
> +unsigned int find_closest(int x, const int *a, unsigned int as)
> +{
> +	unsigned int array_size = as - 1;
> +	int mid_x, left, right;
> +	unsigned int i;
> +
> +	for (i = 0; i < array_size; i++) {
> +		mid_x = (a[i] + a[i + 1]) / 2;
> +		if (x <= mid_x) {
> +			left = x - a[i];
> +			right = a[i + 1] - x;
> +			if (right < left)
> +				i++;
> +			break;
> +		}
> +	}
> +
> +	return i;
> +}
> +EXPORT_SYMBOL_GPL(find_closest);
> +
> +/**
> + * find_closest_descending - locate the closest element in a sorted array
> + * @x: The reference value.
> + * @a: The array in which to look for the closest element. Must be sorted
> + *  in descending order.
> + * @as: Size of 'a'.
> + *

Would repeat the Returns: section here for completeness.

> + * Similar to find_closest() but 'a' is expected to be sorted in descending
> + * order.

This seems redundant since @a already says this.

>             The iteration is done in reverse order, so that the comparison> + * of 'right' & 'left' also works for unsigned numbers.

This seems like an implementation detail so would be better as a comment inside
the function. Although, since @a is always signed, is this comment actually
still applicable?

> + */
> +unsigned int find_closest_descending(int x, const int *a, unsigned int as)
> +{
> +	unsigned int array_size = as - 1;
> +	int mid_x, left, right;
> +	unsigned int i;
> +
> +	for (i = array_size; i >= 1; i--) {
> +		mid_x = (a[i] + a[i - 1]) / 2;
> +		if (x <= mid_x) {
> +			left = x - a[i];
> +			right = a[i - 1] - x;
> +			if (right < left)
> +				i--;
> +			break;
> +		}
> +	}
> +
> +	return i;
> +}
> +EXPORT_SYMBOL_GPL(find_closest_descending);

Re: [PATCH 0/16] lib: Refactor find_closest() and find_closest_descending() from macros to lib functions

[Guenter Roeck]

On 5/15/25 01:13, Alexandru Soponar wrote:
> This patch series converts the find_closest() and find_closest_descending() macros
> into proper library functions. The conversion moves these utilities from macro
> implementations in util_macros.h to standard C functions in lib/find_closest.c.
> 
> The first 15 patches modify individual callers across hwmon, iio, leds, regulator,
> and watchdog subsystems to ensure they work correctly with the new function-based
> implementation. This maintains compatibility while allowing the final conversion.
> 
> The final patch implements the actual refactoring by moving the code to
> lib/find_closest.c. This approach was chosen based on discussions between
> Andrew Morton and Alexandru Ardelean[1], who suggested that a non-inline
> implementation would be appropriate given the size of the functions.
> 
> The refactoring avoids of macro expansion-related issues and proper function
> prototypes with well-defined parameter types.
> 
> Links:
> [1] https://lore.kernel.org/lkml/20241105145406.554365-1-aardelean@baylibre.com/
> 
> Alexandru Soponar (16):
>    hwmon: w83795: Fix type incompatibility with non-macro find_closest
>    hwmon: emc1403: Fix type incompatibility with non-macro find_closest
>    hwmon: ina3221: Fix type incompatibility with non-macro find_closest
>    hwmon: lm95234: Fix type incompatibility with non-macro find_closest
>    hwmon: max1619: Fix type incompatibility with non-macro find_closest
>    hwmon: lm75: Fix type incompatibility with non-macro find_closest
>    hwmon: ltc4282: Fix type incompatibility with non-macro find_closest
>    hwmon: max6639: Fix type incompatibility with non-macro find_closest
>    hwmon: max20740: Fix type incompatibility with non-macro find_closest
>    iio: ad7606: Fix type incompatibility with non-macro find_closest
>    iio: mcp3564: Fix type incompatibility with non-macro find_closest
>    iio: max44009: Fix type incompatibility with non-macro find_closest
>    leds: eds-mt6370-rgb: Fix type incompatibility with find_closest()
>    regulator: max77857: Fix type incompatibility with find_closest()
>    watchdog: simatic-ipc-wdt: Fix type incompatibility with
>      find_closest()

For the hwmon and watchdog patches:

Acked-by: Guenter Roeck <linux@roeck-us.net>