Hi Hans, On Friday 11 January 2013 13:22:08 Hans Verkuil wrote: > On Fri January 11 2013 13:13:47 Laurent Pinchart wrote: > > Hi Hans, > > > > Thanks for the patch. This is much better in my opinion, please see below > > for two small comments. > > > > On Friday 11 January 2013 12:26:03 Hans Verkuil wrote: > > > From: Hans Verkuil <hans.verkuil@xxxxxxxxx> > > > > > > The documentation of the error_idx field was incomplete and confusing. > > > This patch improves it. > > > > > > Signed-off-by: Hans Verkuil <hans.verkuil@xxxxxxxxx> > > > --- > > > > > > .../DocBook/media/v4l/vidioc-g-ext-ctrls.xml | 44 > > > +++++++++++++---- > > > 1 file changed, 37 insertions(+), 7 deletions(-) > > > > > > diff --git a/Documentation/DocBook/media/v4l/vidioc-g-ext-ctrls.xml > > > b/Documentation/DocBook/media/v4l/vidioc-g-ext-ctrls.xml index > > > 0a4b90f..e9f9735 100644 > > > --- a/Documentation/DocBook/media/v4l/vidioc-g-ext-ctrls.xml > > > +++ b/Documentation/DocBook/media/v4l/vidioc-g-ext-ctrls.xml > > > @@ -199,13 +199,43 @@ also be zero.</entry> > > > > > > <row> > > > > > > <entry>__u32</entry> > > > <entry><structfield>error_idx</structfield></entry> > > > > > > - <entry>Set by the driver in case of an error. If it is equal > > > -to <structfield>count</structfield>, then no actual changes were made > > > -to controls. In other words, the error was not associated with setting > > > -a particular control. If it is another value, then only the controls up > > > -to <structfield>error_idx-1</structfield> were modified and control > > > -<structfield>error_idx</structfield> is the one that caused the error. > > > -The <structfield>error_idx</structfield> value is undefined if the > > > -ioctl returned 0 (success).</entry> > > > + <entry><para>Set by the driver in case of an error. If the error > > > +is associated with a particular control, then > > > +<structfield>error_idx</structfield> is set to the index of that > > > +control. If the error is not related to a specific control, or the > > > +pre-validation step failed (see below), then > > > +<structfield>error_idx</structfield> is set to > > > +<structfield>count</structfield>. The value is undefined if the ioctl > > > +returned 0 (success).</para> > > > + > > > +<para>Before controls are read from/written to hardware a > > > +pre-validation > > > > Maybe s/pre-validation/validation/ through the text ? We have a single > > validation step, it feels a bit weird to talk about pre-validation when > > there's no further validation :-) > > OK. > > > > +step takes place: this checks if all controls in the list are all valid > > > > s/all valid/valid/ ? > > Indeed. > > > > +controls, if no attempt is made to write to a read-only control or read > > > +from a write-only control, and any other up-front checks that can be > > > done > > > +without accessing the hardware.</para> > > How about adding this sentence to the end of the paragraph: > > "The exact validations done during this step are driver dependent since some > checks might require hardware access for some devices, thus making it > impossible to do those checks up-front. However, drivers should make a > best-effort to do as many up-front checks as possible." Sounds very good to me. With all those changes, Acked-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> -- Regards, Laurent Pinchart -- 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
