[PATCH 1/3] video: Introduce video_sync call

[Simon Glass]

Hi Michal,

On Mon, 14 Dec 2020 at 01:39, Michal Simek <michal.simek at xilinx.com> wrote:
>
> Hi Simon,
>
> On 12. 12. 20 16:35, Simon Glass wrote:
> > Hi Michal,
> >
> > On Thu, 3 Dec 2020 at 02:13, Michal Simek <michal.simek at xilinx.com> wrote:
> >>
> >> Some drivers like LCD connected via SPI requires explicit sync function
> >> which copy framebuffer content over SPI to controller to display.
> >> This hook doesn't exist yet that's why introduce it via video operations.
> >>
> >> Signed-off-by: Michal Simek <michal.simek at xilinx.com>
> >> ---
> >>
> >> Simon: Please review this. I didn't find existing way how this can be done
> >> that's why I am introducing this hook. Also maybe name can be named a
> >> little bit differently. That's why waiting for better suggestion.
> >> ---
> >>  drivers/video/video-uclass.c |  5 +++++
> >>  include/video.h              | 13 +++++++++++++
> >>  2 files changed, 18 insertions(+)
> >
> >> diff --git a/drivers/video/video-uclass.c b/drivers/video/video-uclass.c
> >> index 650891e49dd0..ba52a6c7125b 100644
> >> --- a/drivers/video/video-uclass.c
> >> +++ b/drivers/video/video-uclass.c
> >> @@ -174,6 +174,11 @@ void video_set_default_colors(struct udevice *dev, bool invert)
> >>  /* Flush video activity to the caches */
> >>  void video_sync(struct udevice *vid, bool force)
> >>  {
> >> +       struct video_ops *ops = video_get_ops(vid);
> >> +
> >> +       if (ops && ops->video_sync)
> >> +               (void)ops->video_sync(vid);
> >
> > We should update video_sync() to return an error.
>
> I sent v2 with fixing this.
>
> >
> >> +
> >>         /*
> >>          * flush_dcache_range() is declared in common.h but it seems that some
> >>          * architectures do not actually implement it. Is there a way to find
> >> diff --git a/include/video.h b/include/video.h
> >> index 9d09d2409af6..acac3f6b3c8d 100644
> >> --- a/include/video.h
> >> +++ b/include/video.h
> >> @@ -115,7 +115,20 @@ struct video_priv {
> >>  };
> >>
> >>  /* Placeholder - there are no video operations at present */
> >
> > Need to update comment
>
> Removed.
>
> >
> >> +/**
> >> + * struct video_ops - structure for keeping video operations
> >> + */
> >>  struct video_ops {
> >> +       /**
> >> +        * video_sync - Synchronize FB with device
> >> +        *
> >> +        * Some device like SPI based LCD displays needs synchronization when
> >> +        * data in an FB is available. For these devices implement video_sync
> >> +        * hook to call a sync function
> >> +        *
> >> +        * @vid:        Video device udevice structure
> >
> > @return
>
> I have looked at kernel-doc format and completely redo this to pass
> kernel-doc script.
> There are a lot of issues reported by that script. Would be good to run
> it by patman automatically to be more visible for everybody.

Yes that would be nice.

Regards,
Simon