Hi Laurent, On Fri, Sep 4, 2020 at 3:25 AM Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> wrote: > > Hi Prabhakar, > > On Thu, Sep 03, 2020 at 03:53:18PM +0100, Lad, Prabhakar wrote: > > On Wed, Aug 19, 2020 at 3:08 PM Hans Verkuil wrote: > > > On 03/08/2020 21:21, Niklas wrote: > > > > On 2020-08-03 19:11:32 +0100, Lad, Prabhakar wrote: > > > >> On Sat, Aug 1, 2020 at 10:04 AM Niklas wrote: > > > >>> On 2020-07-31 10:29:05 +0100, Lad Prabhakar wrote: > > > >>>> The crop and compose settings for VIN in non mc mode werent updated > > > >>>> in s_fmt call this resulted in captured images being clipped. > > > >>>> > > > >>>> With the below sequence on the third capture where size is set to > > > >>>> 640x480 resulted in clipped image of size 320x240. > > > >>>> > > > >>>> high(640x480) -> low (320x240) -> high (640x480) > > > >>>> > > > >>>> This patch makes sure the VIN crop and compose settings are updated. > > > >>> > > > >>> This is clearly an inconsistency in the VIN driver that should be fixed. > > > >>> But I think the none-mc mode implements the correct behavior. That is > > > >>> that S_FMT should not modify the crop/compose rectangles other then make > > > >>> sure they don't go out of bounds. This is an area we tried to clarify in > > > >>> the past but I'm still not sure what the correct answer to. > > > >>> > > > >> What should be the exact behaviour of the bridge driver for s_fmt > > > >> call. Should the crop/compose settings be updated for every s_fmt > > > >> callback or should they be only updated on s_selection callback. > > > >> Currently the non-mc rcar-vin doesnt update the crop/compose setting > > > >> in s_fmt callback due to which I see the above issue as mentioned. > > > > > > > > This is not entirely correct. It does update the crop and compose > > > > rectangles on s_fmt, it makes sure they are not out-of-bounds for the > > > > new format if it's accepted by s_fmt. See v4l2_rect_map_inside() calls > > > > in the snippet bellow. > > > > > > For non-mc mode s_fmt must update any crop/compose rectangles to ensure that > > > they are not out-of-bounds. But for mc mode the validation is done when you > > > start streaming, so I think s_fmt won't make any changes in that mode. > > > > Thank you Hans. > > > > > Double-check that with Laurent, though... > > > > Niklas/Laurent - How do we proceed on this ? > > MC devices rely on userspace to propagate formats between entities, and > on kernelspace to propagate formats within entities. This is documented > in https://linuxtv.org/downloads/v4l-dvb-apis/userspace-api/v4l/dev-subdev.html. > The configuration of an entity (formats and selection rectangles) must > be valid at all times. Subdev drivers should thus either adjust or reset > the crop and selection rectangles. The specification isn't clear on > which behaviour should be implemented, the only related text is > > "Sub-devices that scale frames using variable scaling factors should > reset the scale factors to default values when sink pads formats are > modified. If the 1:1 scaling ratio is supported, this means that source > pads formats should be reset to the sink pads formats." > > I would recommend resetting as the default behaviour. In any case, > adjustements are needed to ensure that the configuration remains valid. > In that case can I have your Ack to the patch please. Cheers, Prabhakar
