v4l2-subdev missing video ops

v4l2-subdev missing video ops

[Pete Eberlein]

Hello Hans,

I'm looking at converting the go7007 staging driver to use the subdev
API.  I don't see any v4l2_subdev_video_ops for VIDIOC_S_INPUT nor
VIDIOC_S_STD.  Were those overlooked, or should I use the generic
v4l2_subdev_core_ops->ioctl?  (The chip in particular does not have a
tuner, but it does have multiple inputs (svidio, composite) and supports
NTSC or PAL.)

Thanks.
-- 
Pete Eberlein
Sensoray Co., Inc.
Email: pete@sensoray.com
http://www.sensoray.com

Re: v4l2-subdev missing video ops

[Andy Walls]

On Thu, 2009-03-19 at 16:55 -0700, Pete Eberlein wrote:
> Hello Hans,
> 
> I'm looking at converting the go7007 staging driver to use the subdev
> API.  I don't see any v4l2_subdev_video_ops for VIDIOC_S_INPUT

I believe you want

v4l2_subdev_video_ops.s_routing
and
v4l2_subdev_audio_ops.s_routing

to effect an input change.


>  nor
> VIDIOC_S_STD. 

The cx25840 module and the cx18 driver use

v4l2_subdev_tuner_ops.s_std

for the digitizer, whether or not it's a tuner input for which the
standard is being set.

A quick grep in linux/drivers/media/video:

$ grep -R -B3  '\.s_std[^_]' *

shows this is likely the case for quite a driver modules.

Regards,
Andy

>  Were those overlooked, or should I use the generic
> v4l2_subdev_core_ops->ioctl?
>   (The chip in particular does not have a
> tuner, but it does have multiple inputs (svidio, composite) and supports
> NTSC or PAL.)
>
> Thanks.

Re: v4l2-subdev missing video ops

[Hans Verkuil]

On Friday 20 March 2009 00:55:20 Pete Eberlein wrote:
> Hello Hans,
>
> I'm looking at converting the go7007 staging driver to use the subdev
> API. 

Hoorah! :-)

> I don't see any v4l2_subdev_video_ops for VIDIOC_S_INPUT nor 
> VIDIOC_S_STD.  Were those overlooked, or should I use the generic
> v4l2_subdev_core_ops->ioctl?  (The chip in particular does not have a
> tuner, but it does have multiple inputs (svidio, composite) and supports
> NTSC or PAL.)

S_STD exists, but it is in tuner_ops. I know, I know, that's the wrong 
place. I'll move it to video_ops once all conversions are done.

S_INPUT must not be used in subdevices. S_INPUT deals with user-level inputs 
(e.g. "Composite", "S-Video", "Tuner"), not with the sub-device-level 
inputs/outputs (e.g. PIN-X, PIN-Y). Sub-devices know nothing about the 
user-level since that's a board-level informations. Sub-devices only know 
about their own input and output pins. The adapter driver is responsible 
for mapping an S_INPUT ioctl to video/s_routing and audio/s_routing subdev 
ops. These routing commands tell the sub-device on what pin(s) it receives 
its input data and what pin(s) are used for the output.

What values you put in the v4l2_routing struct is sub-device dependent and 
is defined in the include/media/<subdev>.h header.

Regards,

	Hans

-- 
Hans Verkuil - video4linux developer - sponsored by TANDBERG