Hi Laurent, On Fri, Nov 30, 2018 at 01:07:53AM +0200, Laurent Pinchart wrote: > Hello Bing, > > On Wednesday, 7 November 2018 06:16:47 EET Bing Bu Cao wrote: > > On 11/01/2018 08:03 PM, Sakari Ailus wrote: > > > On Mon, Oct 29, 2018 at 03:22:54PM -0700, Yong Zhi wrote: > > [snip] > > > >> ImgU media topology print: > > >> > > >> # media-ctl -d /dev/media0 -p > > >> Media controller API version 4.19.0 > > >> > > >> Media device information > > >> ------------------------ > > >> driver ipu3-imgu > > >> model ipu3-imgu > > >> serial > > >> bus info PCI:0000:00:05.0 > > >> hw revision 0x80862015 > > >> driver version 4.19.0 > > >> > > >> Device topology > > >> - entity 1: ipu3-imgu 0 (5 pads, 5 links) > > >> type V4L2 subdev subtype Unknown flags 0 > > >> device node name /dev/v4l-subdev0 > > >> pad0: Sink > > >> [fmt:UYVY8_2X8/1920x1080 field:none colorspace:unknown > > > > > > This doesn't seem right. Which formats can be enumerated from the pad? > > > > > >> crop:(0,0)/1920x1080 > > >> compose:(0,0)/1920x1080] > > > > > > Does the compose rectangle affect the scaling on all outputs? > > > > Sakari, driver use crop and compose targets to help set input-feeder and BDS > > output resolutions which are 2 key block of whole imaging pipeline, not the > > actual ending output, but they will impact the final output. > > > > >> <- "ipu3-imgu 0 input":0 [] > > > > > > Are there links that have no useful link configuration? If so, you should > > > set them enabled and immutable in the driver. > > > > The enabled status of input pads is used to get which pipe that user is > > trying to enable (ipu3_link_setup()), so it could not been set as immutable. > > Each pipe needs an input in order to operate, so from that point of view the > input is mandatory. Why can't we make this link immutable, and use the stream > state (VIDIOC_STREAMON/VIDIOC_STREAMOFF) to enable/disable the pipes ? There are only two options (AFAIK) in choosing the firmware, and by configuring the links this is better visible to the user: the links the state of which can be changed are not immutable. The driver can also obtain the explicit pipeline configuration, which makes the implementation more simple. -- Regards, Sakari Ailus sakari.ailus@xxxxxxxxxxxxxxx
