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| author | Guenter Roeck <linux@roeck-us.net> | 2014-04-13 09:15:09 -0700 |
|---|---|---|
| committer | Guenter Roeck <linux@roeck-us.net> | 2014-05-21 16:02:26 -0700 |
| commit | 9028ff8e3dd207375d2459079f728322671069ac (patch) | |
| tree | 576b41634eafdbd43a50ed5eaa3c9a3981b7c989 /drivers/hwmon | |
| parent | a0ac840d99fa7c2ebf5a3df0367992722a92ca65 (diff) | |
| download | linux-9028ff8e3dd207375d2459079f728322671069ac.tar.gz linux-9028ff8e3dd207375d2459079f728322671069ac.tar.bz2 linux-9028ff8e3dd207375d2459079f728322671069ac.zip | |
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: Guenter Roeck <linux@roeck-us.net>
Diffstat (limited to 'drivers/hwmon')
| -rw-r--r-- | drivers/hwmon/lm80.c | 17 |
1 files changed, 3 insertions, 14 deletions
diff --git a/drivers/hwmon/lm80.c b/drivers/hwmon/lm80.c index bd0a1ebbf867..8e9a0b1dc437 100644 --- a/drivers/hwmon/lm80.c +++ b/drivers/hwmon/lm80.c @@ -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) \ |