Re: [PATCH 1/9] imx074: don't call imx074_find_datafmt() twice

Hans Verkuil
2015-05-04T07:22:13Z

On 05/03/2015 07:54 PM, Guennadi Liakhovetski wrote:
> Hi Hans,
>
> Thanks for fixing the drivers!
>
> On Sun, 3 May 2015, Hans Verkuil wrote:
>
>> From: Hans Verkuil <hans.verkuil@cisco.com>
>>
>> Simplify imx074_set_fmt().
>>
>> Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
>> Reported-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
>> ---
>> drivers/media/i2c/soc_camera/imx074.c | 7 ++++---
>> 1 file changed, 4 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/media/i2c/soc_camera/imx074.c b/drivers/media/i2c/soc_camera/imx074.c
>> index f68c235..4226f06 100644
>> --- a/drivers/media/i2c/soc_camera/imx074.c
>> +++ b/drivers/media/i2c/soc_camera/imx074.c
>> @@ -171,8 +171,9 @@ static int imx074_set_fmt(struct v4l2_subdev *sd,
>> /* MIPI CSI could have changed the format, double-check */
>> if (format->which == V4L2_SUBDEV_FORMAT_ACTIVE)
>> return -EINVAL;
>> - mf->code = imx074_colour_fmts[0].code;
>> - mf->colorspace = imx074_colour_fmts[0].colorspace;
>> + fmt = imx074_colour_fmts;
>> + mf->code = fmt->code;
>> + mf->colorspace = fmt->colorspace;
>
> Uhm, why this change? I understand, that this is equivalent code, but (1)
> is it at all related to the change? and (2) imx074_colour_fmts is an
> array, so, I'd prefer to keep it as is. I do use pointer arithmetics for
> array, but then I'd do something like

Ah, I missed the FORMAT_ACTIVE check just before these lines. You are right,
this change is not needed.

Regards,

Hans

>
> + fmt = imx074_colour_fmts + 0;
> + mf->code = fmt->code;
> + mf->colorspace = fmt->colorspace;
>
> which looks silly:) And then - even more importantly - you overwrite the
> fmt variable, which is then used below instead of calling
> imx074_find_datafmt() again. So, now you assign a (theoretically)
> different value to priv->fmt. I know that array only has one element and
> imx074_find_datafmt() will anyway just return it, but, I don't see why
> this change is needed?
>
> Thanks
> Guennadi
>
>> }
>>
>> mf->width = IMX074_WIDTH;
>> @@ -180,7 +181,7 @@ static int imx074_set_fmt(struct v4l2_subdev *sd,
>> mf->field = V4L2_FIELD_NONE;
>>
>> if (format->which == V4L2_SUBDEV_FORMAT_ACTIVE)
>> - priv->fmt = imx074_find_datafmt(mf->code);
>> + priv->fmt = fmt;
>> else
>> cfg->try_fmt = *mf;
>>
>> --
>> 2.1.4
>>