diff options
| author | Rasmus Villemoes <linux@rasmusvillemoes.dk> | 2015-01-22 23:44:14 +0100 |
|---|---|---|
| committer | Guenter Roeck <linux@roeck-us.net> | 2015-01-25 21:24:00 -0800 |
| commit | 2c3b1189fdca2f512187a670aeb295f901c10d87 (patch) | |
| tree | b977b79ce3df7b3ebcff4c4e2290f2ea72600f01 /drivers/hwmon/adc128d818.c | |
| parent | 984faa1fb9175720828bf6604f936dff3f17b995 (diff) | |
hwmon: (adc128d818) Do proper sign extension
data->temp[index] has type s16. Because of C's promotion rules,
(data->temp[index] << 7) >> 7 is exactly the same as
data->temp[index]. The intention was to use bit 8 as a sign bit, so do
that using the existing API.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Diffstat (limited to 'drivers/hwmon/adc128d818.c')
| -rw-r--r-- | drivers/hwmon/adc128d818.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/hwmon/adc128d818.c b/drivers/hwmon/adc128d818.c index 0625e50d7a6..ad2b47e4034 100644 --- a/drivers/hwmon/adc128d818.c +++ b/drivers/hwmon/adc128d818.c @@ -27,6 +27,7 @@ #include <linux/err.h> #include <linux/regulator/consumer.h> #include <linux/mutex.h> +#include <linux/bitops.h> /* Addresses to scan * The chip also supports addresses 0x35..0x37. Don't scan those addresses @@ -189,7 +190,7 @@ static ssize_t adc128_show_temp(struct device *dev, if (IS_ERR(data)) return PTR_ERR(data); - temp = (data->temp[index] << 7) >> 7; /* sign extend */ + temp = sign_extend32(data->temp[index], 8); return sprintf(buf, "%d\n", temp * 500);/* 0.5 degrees C resolution */ } |