Commit 9ca66967 authored by Daniel Matyas's avatar Daniel Matyas Committed by Guenter Roeck
Browse files

hwmon: (max31827) Make code cleaner 



Used enums and while loops to replace switch for selecting and getting
update interval from conversion rate bits.

Divided the write_alarm_val function into 2 functions. The new function
is more generic: it can be used not only for alarm writes, but for any
kind of writes which require the device to be in shutdown mode.

Signed-off-by: default avatarDaniel Matyas <daniel.matyas@analog.com>
Link: https://lore.kernel.org/r/20230919093456.10592-1-daniel.matyas@analog.com


[groeck: Reverted error return value change (EOPNOTSUPP -> EINVAL)]
Signed-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
parent b344041d

drivers/hwmon/max31827.c

+54 −69
Original line number Diff line number Diff line
@@ -27,18 +27,30 @@ 


#define MAX31827_12_BIT_CNV_TIME	141



#define MAX31827_CNV_1_DIV_64_HZ	0x1

#define MAX31827_CNV_1_DIV_32_HZ	0x2

#define MAX31827_CNV_1_DIV_16_HZ	0x3

#define MAX31827_CNV_1_DIV_4_HZ		0x4

#define MAX31827_CNV_1_HZ		0x5

#define MAX31827_CNV_4_HZ		0x6

#define MAX31827_CNV_8_HZ		0x7



#define MAX31827_16_BIT_TO_M_DGR(x)	(sign_extend32(x, 15) * 1000 / 16)

#define MAX31827_M_DGR_TO_16_BIT(x)	(((x) << 4) / 1000)

#define MAX31827_DEVICE_ENABLE(x)	((x) ? 0xA : 0x0)



enum max31827_cnv {

	MAX31827_CNV_1_DIV_64_HZ = 1,

	MAX31827_CNV_1_DIV_32_HZ,

	MAX31827_CNV_1_DIV_16_HZ,

	MAX31827_CNV_1_DIV_4_HZ,

	MAX31827_CNV_1_HZ,

	MAX31827_CNV_4_HZ,

	MAX31827_CNV_8_HZ,

};



static const u16 max31827_conversions[] = {

	[MAX31827_CNV_1_DIV_64_HZ] = 64000,

	[MAX31827_CNV_1_DIV_32_HZ] = 32000,

	[MAX31827_CNV_1_DIV_16_HZ] = 16000,

	[MAX31827_CNV_1_DIV_4_HZ] = 4000,

	[MAX31827_CNV_1_HZ] = 1000,

	[MAX31827_CNV_4_HZ] = 250,

	[MAX31827_CNV_8_HZ] = 125,

};



struct max31827_state {

	/*

	 * Prevent simultaneous access to the i2c client.
@@ -54,15 +66,13 @@ static const struct regmap_config max31827_regmap = { 
	.max_register = 0xA,

};



static int write_alarm_val(struct max31827_state *st, unsigned int reg,

			   long val)

static int shutdown_write(struct max31827_state *st, unsigned int reg,

			  unsigned int val)

{

	unsigned int cfg;

	unsigned int tmp;

	unsigned int cnv_rate;

	int ret;



	val = MAX31827_M_DGR_TO_16_BIT(val);



	/*

	 * Before the Temperature Threshold Alarm and Alarm Hysteresis Threshold

	 * register values are changed over I2C, the part must be in shutdown
@@ -82,9 +92,10 @@ static int write_alarm_val(struct max31827_state *st, unsigned int reg, 
	if (ret)

		goto unlock;



	tmp = cfg & ~(MAX31827_CONFIGURATION_1SHOT_MASK |

	cnv_rate = MAX31827_CONFIGURATION_CNV_RATE_MASK & cfg;

	cfg = cfg & ~(MAX31827_CONFIGURATION_1SHOT_MASK |

		      MAX31827_CONFIGURATION_CNV_RATE_MASK);

	ret = regmap_write(st->regmap, MAX31827_CONFIGURATION_REG, tmp);

	ret = regmap_write(st->regmap, MAX31827_CONFIGURATION_REG, cfg);

	if (ret)

		goto unlock;
@@ -92,13 +103,23 @@ static int write_alarm_val(struct max31827_state *st, unsigned int reg, 
	if (ret)

		goto unlock;



	ret = regmap_write(st->regmap, MAX31827_CONFIGURATION_REG, cfg);

	ret = regmap_update_bits(st->regmap, MAX31827_CONFIGURATION_REG,

				 MAX31827_CONFIGURATION_CNV_RATE_MASK,

				 cnv_rate);



unlock:

	mutex_unlock(&st->lock);

	return ret;

}



static int write_alarm_val(struct max31827_state *st, unsigned int reg,

			   long val)

{

	val = MAX31827_M_DGR_TO_16_BIT(val);



	return shutdown_write(st, reg, val);

}



static umode_t max31827_is_visible(const void *state,

				   enum hwmon_sensor_types type, u32 attr,

				   int channel)
@@ -243,32 +264,7 @@ static int max31827_read(struct device *dev, enum hwmon_sensor_types type, 


			uval = FIELD_GET(MAX31827_CONFIGURATION_CNV_RATE_MASK,

					 uval);

			switch (uval) {

			case MAX31827_CNV_1_DIV_64_HZ:

				*val = 64000;

				break;

			case MAX31827_CNV_1_DIV_32_HZ:

				*val = 32000;

				break;

			case MAX31827_CNV_1_DIV_16_HZ:

				*val = 16000;

				break;

			case MAX31827_CNV_1_DIV_4_HZ:

				*val = 4000;

				break;

			case MAX31827_CNV_1_HZ:

				*val = 1000;

				break;

			case MAX31827_CNV_4_HZ:

				*val = 250;

				break;

			case MAX31827_CNV_8_HZ:

				*val = 125;

				break;

			default:

				*val = 0;

				break;

			}

			*val = max31827_conversions[uval];

		}

		break;
@@ -284,6 +280,7 @@ static int max31827_write(struct device *dev, enum hwmon_sensor_types type, 
			  u32 attr, int channel, long val)

{

	struct max31827_state *st = dev_get_drvdata(dev);

	int res = 1;

	int ret;



	switch (type) {
@@ -333,39 +330,27 @@ static int max31827_write(struct device *dev, enum hwmon_sensor_types type, 
			if (!st->enable)

				return -EINVAL;



			switch (val) {

			case 125:

				val = MAX31827_CNV_8_HZ;

				break;

			case 250:

				val = MAX31827_CNV_4_HZ;

				break;

			case 1000:

				val = MAX31827_CNV_1_HZ;

				break;

			case 4000:

				val = MAX31827_CNV_1_DIV_4_HZ;

				break;

			case 16000:

				val = MAX31827_CNV_1_DIV_16_HZ;

				break;

			case 32000:

				val = MAX31827_CNV_1_DIV_32_HZ;

				break;

			case 64000:

				val = MAX31827_CNV_1_DIV_64_HZ;

				break;

			default:

			/*

			 * Convert the desired conversion rate into register

			 * bits. res is already initialized with 1.

			 *

			 * This was inspired by lm73 driver.

			 */

			while (res < ARRAY_SIZE(max31827_conversions) &&

			       val < max31827_conversions[res])

				res++;



			if (res == ARRAY_SIZE(max31827_conversions) ||

			    val != max31827_conversions[res])

				return -EINVAL;

			}



			val = FIELD_PREP(MAX31827_CONFIGURATION_CNV_RATE_MASK,

					 val);

			res = FIELD_PREP(MAX31827_CONFIGURATION_CNV_RATE_MASK,

					 res);



			return regmap_update_bits(st->regmap,

						  MAX31827_CONFIGURATION_REG,

						  MAX31827_CONFIGURATION_CNV_RATE_MASK,

						  val);

						  res);

		}

		break;