Re: [PATCH 2/2] [RFC] video: display: Adding frame related ops to MIPI DSI video source struct

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Vikas,

Thank you for the patch.

On Friday 04 January 2013 10:24:04 Vikas Sajjan wrote:
> On 3 January 2013 16:29, Tomasz Figa <t.figa@samsung.com> wrote:
> > On Wednesday 02 of January 2013 18:47:22 Vikas C Sajjan wrote:
> >> From: Vikas Sajjan <vikas.sajjan@linaro.org>
> >> 
> >> Signed-off-by: Vikas Sajjan <vikas.sajjan@linaro.org>
> >> ---
> >> 
> >>  include/video/display.h |    6 ++++++
> >>  1 file changed, 6 insertions(+)
> >> 
> >> diff --git a/include/video/display.h b/include/video/display.h
> >> index b639fd0..fb2f437 100644
> >> --- a/include/video/display.h
> >> +++ b/include/video/display.h
> >> @@ -117,6 +117,12 @@ struct dsi_video_source_ops {
> >> 
> >>       void (*enable_hs)(struct video_source *src, bool enable);
> >> 
> >> +     /* frame related */
> >> +     int (*get_frame_done)(struct video_source *src);
> >> +     int (*clear_frame_done)(struct video_source *src);
> >> +     int (*set_early_blank_mode)(struct video_source *src, int power);
> >> +     int (*set_blank_mode)(struct video_source *src, int power);
> >> +
> > 
> > I'm not sure if all those extra ops are needed in any way.
> > 
> > Looking and Exynos MIPI DSIM driver, set_blank_mode is handling only
> > FB_BLANK_UNBLANK status, which basically equals to the already existing
> > enable operation, while set_early_blank mode handles only
> > FB_BLANK_POWERDOWN, being equal to disable callback.
> 
> Right, exynos_mipi_dsi_blank_mode() only supports FB_BLANK_UNBLANK as
> of now, but FB_BLANK_NORMAL will be supported in future.
> If not for Exynos, i think it will be need for other SoCs which
> support FB_BLANK_UNBLANK and FB_BLANK_NORMAL.

Could you please explain in a bit more details what the set_early_blank_mode 
and set_blank_mode operations do ?

> > Both get_frame_done and clear_frame_done do not look at anything used at
> > the moment and if frame done status monitoring will be ever needed, I
> > think a better way should be implemented.
> 
> You are right, as of now Exynos MIPI DSI Panels are NOT using these
> callbacks, but as you mentioned we will need frame done status monitoring
> anyways, so i included these callbacks here. Will check, if we can implement
> any better method.

Do you expect the entity drivers (and in particular the panel drivers) to 
require frame done notification ? If so, could you explain your use case(s) ?

-- 
Regards,

Laurent Pinchart