Commit 9028ff8e authored by Guenter Roeck's avatar Guenter Roeck
Browse files

hwmon: (lm80) Simplify TEMP_FROM_REG 



TEMP_FROM_REG gets 12 bits of temperature data in the upper 12 bit
of a signed 16 bit parameter, with the integer part (including sign)
in the upper 8 bit and the remainder in bit 4..7. The lower 4 bit of
the 16 bit data is always 0. We can use that information to convert
the temperature directly into display data (1/1000th of degree C).

Note that the stored temperature data is not shifted right as the
comment claimed, so remove that misleading comment.

Signed-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
parent a0ac840d

drivers/hwmon/lm80.c

+3 −14
Original line number Diff line number Diff line
@@ -86,18 +86,7 @@ static inline unsigned char FAN_TO_REG(unsigned rpm, unsigned div) 
#define FAN_FROM_REG(val, div)	((val) == 0 ? -1 : \

				(val) == 255 ? 0 : 1350000/((div) * (val)))



static inline long TEMP_FROM_REG(u16 temp)

{

	long res;



	temp >>= 4;

	if (temp < 0x0800)

		res = 625 * (long) temp;

	else

		res = ((long) temp - 0x01000) * 625;



	return res / 10;

}

#define TEMP_FROM_REG(temp) ((temp) * 125 / 32)



#define TEMP_LIMIT_FROM_REG(val)	(((val) > 0x80 ? \

	(val) - 0x100 : (val)) * 1000)
@@ -124,7 +113,7 @@ struct lm80_data { 
	u8 fan[2];		/* Register value */

	u8 fan_min[2];		/* Register value */

	u8 fan_div[2];		/* Register encoding, shifted right */

	u16 temp;		/* Register values, shifted right */

	s16 temp;		/* Register values */

	u8 temp_hot_max;	/* Register value */

	u8 temp_hot_hyst;	/* Register value */

	u8 temp_os_max;		/* Register value */
@@ -309,7 +298,7 @@ static ssize_t show_temp_input1(struct device *dev, 
	struct lm80_data *data = lm80_update_device(dev);

	if (IS_ERR(data))

		return PTR_ERR(data);

	return sprintf(buf, "%ld\n", TEMP_FROM_REG(data->temp));

	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp));

}



#define show_temp(suffix, value) \

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