[PATCH] iio: lsiio: fix error code handling error

[Linus Walleij <linus.walleij@linaro.org>]

commit acf50b3586f8d8a7530b905e111dda41876d38f4
"tools:iio:lsiio: add error handling"
introduced error handling of errors returned from
read_sysfs_string(), but with a simple if (retval),
missing the fact that these functions return a positive
value if the read was successful.

As a result lsiio regresses and does not show any
devices on my filesystem. Fix this by checking for
only negative error codes.

Cc: Hartmut Knaack <knaack.h@gmx.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
---
 tools/iio/lsiio.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/iio/lsiio.c b/tools/iio/lsiio.c
index b59ee1733924..b2c028cc7cac 100644
--- a/tools/iio/lsiio.c
+++ b/tools/iio/lsiio.c
@@ -70,7 +70,7 @@ static int dump_one_device(const char *dev_dir_name)
 	if (retval != 1)
 		return -EINVAL;
 	retval = read_sysfs_string("name", dev_dir_name, name);
-	if (retval)
+	if (retval < 0)
 		return retval;
 
 	printf("Device %03d: %s\n", dev_idx, name);
@@ -91,7 +91,7 @@ static int dump_one_trigger(const char *dev_dir_name)
 	if (retval != 1)
 		return -EINVAL;
 	retval = read_sysfs_string("name", dev_dir_name, name);
-	if (retval)
+	if (retval < 0)
 		return retval;
 
 	printf("Trigger %03d: %s\n", dev_idx, name);
-- 
2.4.3