Re: [PATCH v6 11/12] intel-ipu3: Add v4l2 driver based on media framework

[Tomasz Figa <tfiga@xxxxxxxxxxxx>]

+Hans Verkuil

(I think he commented on earlier revisions. Please keep anyone who
commented before on CC when sending further revisions.)

On Mon, Sep 17, 2018 at 5:04 AM Zhi, Yong <yong.zhi@xxxxxxxxx> wrote:
>
> Hi, Tomasz,
>
> Sorry for the delay in responding to your review.
>
> > -----Original Message-----
> > From: linux-media-owner@xxxxxxxxxxxxxxx [mailto:linux-media-
> > owner@xxxxxxxxxxxxxxx] On Behalf Of Tomasz Figa
> > Sent: Monday, July 2, 2018 2:50 AM
> > To: Zhi, Yong <yong.zhi@xxxxxxxxx>
> > Cc: Linux Media Mailing List <linux-media@xxxxxxxxxxxxxxx>; Sakari Ailus
> > <sakari.ailus@xxxxxxxxxxxxxxx>; Mani, Rajmohan
> > <rajmohan.mani@xxxxxxxxx>; Toivonen, Tuukka
> > <tuukka.toivonen@xxxxxxxxx>; Hu, Jerry W <jerry.w.hu@xxxxxxxxx>; Zheng,
> > Jian Xu <jian.xu.zheng@xxxxxxxxx>; Vijaykumar, Ramya
> > <ramya.vijaykumar@xxxxxxxxx>
> > Subject: Re: [PATCH v6 11/12] intel-ipu3: Add v4l2 driver based on media
> > framework
> >
> > Hi Yong,
> >
> > On Fri, Mar 30, 2018 at 11:15 AM Yong Zhi <yong.zhi@xxxxxxxxx> wrote:
> > [snip]
> > > +static int ipu3_vidioc_enum_input(struct file *file, void *fh,
> > > +                                 struct v4l2_input *input) {
> > > +       if (input->index > 0)
> > > +               return -EINVAL;
> > > +       strlcpy(input->name, "camera", sizeof(input->name));
> > > +       input->type = V4L2_INPUT_TYPE_CAMERA;
> > > +
> > > +       return 0;
> > > +}
> > > +
> > > +static int ipu3_vidioc_g_input(struct file *file, void *fh, unsigned
> > > +int *input) {
> > > +       *input = 0;
> > > +
> > > +       return 0;
> > > +}
> > > +
> > > +static int ipu3_vidioc_s_input(struct file *file, void *fh, unsigned
> > > +int input) {
> > > +       return input == 0 ? 0 : -EINVAL; }
> > > +
> > > +static int ipu3_vidioc_enum_output(struct file *file, void *fh,
> > > +                                  struct v4l2_output *output) {
> > > +       if (output->index > 0)
> > > +               return -EINVAL;
> > > +       strlcpy(output->name, "camera", sizeof(output->name));
> > > +       output->type = V4L2_INPUT_TYPE_CAMERA;
> > > +
> > > +       return 0;
> > > +}
> > > +
> > > +static int ipu3_vidioc_g_output(struct file *file, void *fh,
> > > +                               unsigned int *output) {
> > > +       *output = 0;
> > > +
> > > +       return 0;
> > > +}
> > > +
> > > +static int ipu3_vidioc_s_output(struct file *file, void *fh,
> > > +                               unsigned int output) {
> > > +       return output == 0 ? 0 : -EINVAL; }
> >
> > Do we really need to implement the 6 functions above? They don't seem to
> > be doing anything useful.
> >
>
> They are here to pass v4l2-compliance test. I can add a note in next update for their purpose.  We can remove them in the future when defaults callbacks are available for those ops.
>

Strange.

Hans, is it really mandatory to implement dmmy output/input setting if
there is no output/input switching capability?

Best regards,
Tomasz