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@xxxxxxxxxxxxxxxxxx> --- drivers/hwmon/adc128d818.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/hwmon/adc128d818.c b/drivers/hwmon/adc128d818.c index 0625e50d7a6e..ad2b47e40345 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 */ } -- 2.1.3 _______________________________________________ lm-sensors mailing list lm-sensors@xxxxxxxxxxxxxx http://lists.lm-sensors.org/mailman/listinfo/lm-sensors
