This commit is fixing a smatch warning:
drivers/w1/slaves/w1_ds2413.c:61 state_read() warn: impossible condition '(*buf == 255) => ((-128)-127 == 255)'
by creating additional u8 variable for the bus reading and comparision
Reported-by: kbuild test robot <[email protected]>
Reported-by: Dan Carpenter <[email protected]>
Cc: Dan Carpenter <[email protected]>
Fixes: 3856032a0628 ("w1: ds2413: when the slave is not responding during read, select it again")
Signed-off-by: Mariusz Bialonczyk <[email protected]>
---
drivers/w1/slaves/w1_ds2413.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/drivers/w1/slaves/w1_ds2413.c b/drivers/w1/slaves/w1_ds2413.c
index 21f08ac8a4e0..3364ad276b15 100644
--- a/drivers/w1/slaves/w1_ds2413.c
+++ b/drivers/w1/slaves/w1_ds2413.c
@@ -33,6 +33,7 @@ static ssize_t state_read(struct file *filp, struct kobject *kobj,
struct w1_slave *sl = kobj_to_w1_slave(kobj);
unsigned int retries = W1_F3A_RETRIES;
ssize_t bytes_read = -EIO;
+ u8 state;
dev_dbg(&sl->dev,
"Reading %s kobj: %p, off: %0#10x, count: %zu, buff addr: %p",
@@ -53,12 +54,13 @@ static ssize_t state_read(struct file *filp, struct kobject *kobj,
while (retries--) {
w1_write_8(sl->master, W1_F3A_FUNC_PIO_ACCESS_READ);
- *buf = w1_read_8(sl->master);
- if ((*buf & 0x0F) == ((~*buf >> 4) & 0x0F)) {
+ state = w1_read_8(sl->master);
+ if ((state & 0x0F) == ((~state >> 4) & 0x0F)) {
/* complement is correct */
+ *buf = state;
bytes_read = 1;
goto out;
- } else if (*buf == W1_F3A_INVALID_PIO_STATE) {
+ } else if (state == W1_F3A_INVALID_PIO_STATE) {
/* slave didn't respond, try to select it again */
dev_warn(&sl->dev, "slave device did not respond to PIO_ACCESS_READ, " \
"reselecting, retries left: %d\n", retries);
--
2.19.0.rc1