drivers/rtc/rtc-x1205.c: use sign_extend32() for sign extension

Despite its name, sign_extend32() is safe to use for 8 bit types too.
(See https://lkml.org/lkml/2015/1/18/289).

Signed-off-by: Martin Kepplinger <[email protected]>
Cc: Alessandro Zummo <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
This commit is contained in:
Martin Kepplinger 2015-04-16 12:45:09 -07:00 • committed by Linus Torvalds
commit 86e66604fc

View file

@ -22,6 +22,7 @@
#include <linux/rtc.h>
#include <linux/delay.h>
#include <linux/module.h>
#include <linux/bitops.h>
#define DRV_VERSION "1.0.8"
@ -366,8 +367,7 @@ static int x1205_get_atrim(struct i2c_client *client, int *trim)
* perform sign extension. The formula is
* Catr = (atr * 0.25pF) + 11.00pF.
*/
if (atr & 0x20)
atr |= 0xC0;
atr = sign_extend32(atr, 5);
dev_dbg(&client->dev, "%s: raw atr=%x (%d)\n", __func__, atr, atr);