[PATCH] rtc: s35390a: Make buf an unsigned char in s35390a_init

[Nathan Chancellor]

Clang warns:

drivers/rtc/rtc-s35390a.c:124:27: warning: implicit conversion from
'int' to 'char' changes value from 192 to -64 [-Wconstant-conversion]
        buf = S35390A_FLAG_RESET | S35390A_FLAG_24H;
            ~ ~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~
1 warning generated.

Update buf to be an unsigned char, which matches the size and signedness
of the buf member in struct i2c_msg (__u8).

https://github.com/ClangBuiltLinux/linux/issues/145
Signed-off-by: Nathan Chancellor <natechancellor@xxxxxxxxx>
---
 drivers/rtc/rtc-s35390a.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/rtc/rtc-s35390a.c b/drivers/rtc/rtc-s35390a.c
index 77feb603cd4c..9fd51337cfae 100644
--- a/drivers/rtc/rtc-s35390a.c
+++ b/drivers/rtc/rtc-s35390a.c
@@ -108,7 +108,7 @@ static int s35390a_get_reg(struct s35390a *s35390a, int reg, char *buf, int len)
 
 static int s35390a_init(struct s35390a *s35390a)
 {
-	char buf;
+	unsigned char buf;
 	int ret;
 	unsigned initcount = 0;
 
-- 
2.19.1