On 10/31/2014 03:48 PM, Simon Farnsworth wrote: > Documentation for enum v4l2_field did not make it clear that V4L2_FIELD_ANY > is only acceptable as input to the kernel, not as a response from the > driver. > > Make it clear, to stop userspace developers like me assuming it can be > returned by the driver. > > Signed-off-by: Simon Farnsworth <simon.farnsworth@xxxxxxxxxxxx> > --- > Documentation/DocBook/media/v4l/io.xml | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/Documentation/DocBook/media/v4l/io.xml b/Documentation/DocBook/media/v4l/io.xml > index e5e8325..8918bb2 100644 > --- a/Documentation/DocBook/media/v4l/io.xml > +++ b/Documentation/DocBook/media/v4l/io.xml > @@ -1422,7 +1422,10 @@ one of the <constant>V4L2_FIELD_NONE</constant>, > <constant>V4L2_FIELD_BOTTOM</constant>, or > <constant>V4L2_FIELD_INTERLACED</constant> formats is acceptable. > Drivers choose depending on hardware capabilities or e. g. the > -requested image size, and return the actual field order. &v4l2-buffer; > +requested image size, and return the actual field order. If multiple > +field orders are possible the driver must choose one of the possible > +field orders during &VIDIOC-S-FMT; or &VIDIOC-TRY-FMT; and must not > +return V4L2_FIELD_ANY. &v4l2-buffer; I would phrase it slightly differently: "Drivers must never return <constant>V4L2_FIELD_ANY</constant>. If multiple field orders are possible the driver must choose one of the possible field orders during &VIDIOC-S-FMT; or &VIDIOC-TRY-FMT;." Regards, Hans > <structfield>field</structfield> can never be > <constant>V4L2_FIELD_ANY</constant>.</entry> > </row> > -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
