From: Mariusz Bialonczyk <manio@skyboo.net>
To: linux-kernel@vger.kernel.org, Greg Kroah-Hartman <greg@kroah.com>
Cc: Mariusz Bialonczyk <manio@skyboo.net>,
Dan Carpenter <dan.carpenter@oracle.com>
Subject: [PATCH] w1: ds2413: fix state byte comparision
Date: Thu, 30 May 2019 09:51:25 +0200 [thread overview]
Message-ID: <20190530075125.27379-1-manio@skyboo.net> (raw)
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 <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: 3856032a0628 ("w1: ds2413: when the slave is not responding during read, select it again")
Signed-off-by: Mariusz Bialonczyk <manio@skyboo.net>
---
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
reply other threads:[~2019-05-30 7:51 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190530075125.27379-1-manio@skyboo.net \
--to=manio@skyboo.net \
--cc=dan.carpenter@oracle.com \
--cc=greg@kroah.com \
--cc=linux-kernel@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).