Hi Tom,
On Fri, Aug 28, 2020 at 07:55:18AM -0700, trix@xxxxxxxxxx wrote:
> From: Tom Rix <trix@xxxxxxxxxx>
>
> clang static analysis flags this representative problem
>
> drivers/media/i2c/ov7670.c:1463:9: warning: Assigned
> value is garbage or undefined
> *value = gain;
> ^ ~~~~
>
> gain is set by a successful call to ov7670_read()
>
> So check that ov7670_read() is successful.
>
> The remaining static analysis problems are false positives.
> There appears to be a limitation with checking the
> aggregated returns.
>
> Signed-off-by: Tom Rix <trix@xxxxxxxxxx>
> ---
> drivers/media/i2c/ov7670.c | 17 +++++++++++++----
> 1 file changed, 13 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/media/i2c/ov7670.c b/drivers/media/i2c/ov7670.c
> index b42b289faaef..001d4b09db72 100644
> --- a/drivers/media/i2c/ov7670.c
> +++ b/drivers/media/i2c/ov7670.c
> @@ -929,6 +929,8 @@ static int ov7670_set_hw(struct v4l2_subdev *sd, int hstart, int hstop,
> ret = ov7670_write(sd, REG_HSTART, (hstart >> 3) & 0xff);
> ret += ov7670_write(sd, REG_HSTOP, (hstop >> 3) & 0xff);
> ret += ov7670_read(sd, REG_HREF, &v);
> + if (ret)
> + return ret;
Thanks for the patch.
While the patch fixes a bug, could you also fix adding the return values?
These are valid error codes to begin with, but it makes no sense to add
them together.
> v = (v & 0xc0) | ((hstop & 0x7) << 3) | (hstart & 0x7);
> msleep(10);
> ret += ov7670_write(sd, REG_HREF, v);
> @@ -938,6 +940,8 @@ static int ov7670_set_hw(struct v4l2_subdev *sd, int hstart, int hstop,
> ret += ov7670_write(sd, REG_VSTART, (vstart >> 2) & 0xff);
> ret += ov7670_write(sd, REG_VSTOP, (vstop >> 2) & 0xff);
> ret += ov7670_read(sd, REG_VREF, &v);
> + if (ret)
> + return ret;
> v = (v & 0xf0) | ((vstop & 0x3) << 2) | (vstart & 0x3);
> msleep(10);
> ret += ov7670_write(sd, REG_VREF, v);
> @@ -1460,6 +1464,8 @@ static int ov7670_g_gain(struct v4l2_subdev *sd, __s32 *value)
> unsigned char gain;
>
> ret = ov7670_read(sd, REG_GAIN, &gain);
> + if (ret)
> + return ret;
> *value = gain;
> return ret;
> }
> @@ -1470,11 +1476,14 @@ static int ov7670_s_gain(struct v4l2_subdev *sd, int value)
> unsigned char com8;
>
> ret = ov7670_write(sd, REG_GAIN, value & 0xff);
> + if (ret)
> + return ret;
> /* Have to turn off AGC as well */
> - if (ret == 0) {
> - ret = ov7670_read(sd, REG_COM8, &com8);
> - ret = ov7670_write(sd, REG_COM8, com8 & ~COM8_AGC);
> - }
> + ret = ov7670_read(sd, REG_COM8, &com8);
> + if (ret)
> + return ret;
> + ret = ov7670_write(sd, REG_COM8, com8 & ~COM8_AGC);
> +
> return ret;
> }
>
--
Regards,
Sakari Ailus
