[patch 36/47] ov7670: clean up ov7670_read semantics

Greg KH
2008-07-22T23:30:41Z

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2.6.25-stable review patch. If anyone has any objections, please let us
know.

------------------
From: Andres Salomon <dilinger@queued.net>

commit bca5c2c550f16d2dc2d21ffb7b4712bd0a7d32a9 upstream

Cortland Setlow pointed out a bug in ov7670.c where the result from
ov7670_read() was just being checked for !0, rather than <0. This made me
realize that ov7670_read's semantics were rather confusing; it both fills
in 'value' with the result, and returns it. This is goes against general
kernel convention; so rather than fixing callers, let's fix the function.

This makes ov7670_read return <0 in the case of an error, and 0 upon
success. Thus, code like:

res = ov7670_read(...);
if (!res)
goto error;

.will work properly.

Signed-off-by: Cortland Setlow <csetlow@tower-research.com>
Signed-off-by: Andres Salomon <dilinger@debian.org>
Acked-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
drivers/media/video/ov7670.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

--- a/drivers/media/video/ov7670.c
+++ b/drivers/media/video/ov7670.c
@@ -406,8 +406,10 @@ static int ov7670_read(struct i2c_client
int ret;

ret = i2c_smbus_read_byte_data(c, reg);
- if (ret >= 0)
+ if (ret >= 0) {
*value = (unsigned char) ret;
+ ret = 0;
+ }
return ret;
}

--