RE: [PATCH v8 1/2] media: dt-bindings: media: xilinx: Add Xilinx MIPI CSI-2 Rx Subsystem

From: Vishal Sagar
Date: Thu Jun 06 2019 - 07:58:35 EST


Hi Sakari,

> -----Original Message-----
> From: Sakari Ailus [mailto:sakari.ailus@xxxxxxxxxxxxxxx]
> Sent: Wednesday, June 05, 2019 12:54 AM
> To: Vishal Sagar <vishal.sagar@xxxxxxxxxx>
> Cc: Hyun Kwon <hyunk@xxxxxxxxxx>; laurent.pinchart@xxxxxxxxxxxxxxxx;
> mchehab@xxxxxxxxxx; robh+dt@xxxxxxxxxx; mark.rutland@xxxxxxx; Michal
> Simek <michals@xxxxxxxxxx>; linux-media@xxxxxxxxxxxxxxx;
> devicetree@xxxxxxxxxxxxxxx; hans.verkuil@xxxxxxxxx; linux-arm-
> kernel@xxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Dinesh Kumar
> <dineshk@xxxxxxxxxx>; Sandip Kothari <sandipk@xxxxxxxxxx>; Luca Ceresoli
> <luca@xxxxxxxxxxxxxxxx>; Jacopo Mondi <jacopo@xxxxxxxxxx>
> Subject: Re: [PATCH v8 1/2] media: dt-bindings: media: xilinx: Add Xilinx MIPI
> CSI-2 Rx Subsystem
>
> EXTERNAL EMAIL
>
> Hi Vishal,
>
> On Mon, Jun 03, 2019 at 03:29:30PM +0530, Vishal Sagar wrote:
>
> > +Optional properties:
> > +--------------------
> > +- xlnx,vfb: This is present when Video Format Bridge is enabled.
> > + Without this property the driver won't be loaded as IP won't be able to
> generate
> > + media bus format compliant stream output.
>
> I think we previously concluded that the format will be just different in
> this case. So the description appears incorrect.
>

Referring to your email https://lkml.org/lkml/2019/3/22/1823 in response to v6 patches,
if the video format bridge is not enabled, then the way in which pixels are transported on
the bus don't correspond to the existing media bus formats in Linux.

If not loading the driver is incorrect way, is it ok for the driver to allow same media bus format
for packed and unpacked data type on the sink pad?

Or is it ok for the driver to not validate the media bus format set on the sink pad?

> --
> Sakari Ailus
> sakari.ailus@xxxxxxxxxxxxxxx

Regards
Vishal Sagar