Re: [PATCH 3/3] v4l: ioctl: Set bus_info in v4l_querycap()

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

On Mon, Jan 24, 2022 at 06:02:59PM +0200, Sakari Ailus wrote:
> Hi Laurent,
> 
> On Sun, Jan 23, 2022 at 01:51:10AM +0200, Laurent Pinchart wrote:
> 
> ...
> 
> > > diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
> > > index 642cb90f457c..81ebf6cca522 100644
> > > --- a/drivers/media/v4l2-core/v4l2-ioctl.c
> > > +++ b/drivers/media/v4l2-core/v4l2-ioctl.c
> > > @@ -18,6 +18,7 @@
> > >  
> > >  #include <linux/videodev2.h>
> > >  
> > > +#include <media/media-device.h> /* for media_set_bus_info() */
> > >  #include <media/v4l2-common.h>
> > >  #include <media/v4l2-ioctl.h>
> > >  #include <media/v4l2-ctrls.h>
> > > @@ -1069,6 +1070,8 @@ static int v4l_querycap(const struct v4l2_ioctl_ops *ops,
> > >  	cap->capabilities |= V4L2_CAP_EXT_PIX_FORMAT;
> > >  	cap->device_caps |= V4L2_CAP_EXT_PIX_FORMAT;
> > >  
> > > +	media_set_bus_info(cap->bus_info, vfd->dev_parent);
> > > +
> > 
> > Shouldn't you do this before calling the driver operation, if you want
> > to allow driver overrides ?
> 
> This is done conditionally based on the value of the first byte.

I had missed that.

Isn't it still better to call media_set_bus_info() first, instead of
checking the first byte ?

-- 
Regards,

Laurent Pinchart