Hi Mauro,
On Thu, 14 Jul 2011 13:27:17 -0300, Mauro Carvalho Chehab
<mchehab@xxxxxxxxxx> wrote:
Em 08-07-2011 12:25, Sylwester Nawrocki escreveu:
> Hi Mauro,
>
> The following changes since commit
6068c012c3741537c9f965be5b4249f989aa5efc:
>
> [media] v4l: Document V4L2 control endianness as machine
endianness (2011-07-07 19:26:11 -0300)
>
> are available in the git repository at:
> git://git.infradead.org/users/kmpark/linux-2.6-samsung
s5p-fimc-next
>
> These patches convert FIMC and the sensor driver to media
controller API,
> i.e. a top level media device is added to be able to manage at
runtime
> attached sensors and all video processing entities present in the
SoC.
> An additional subdev at FIMC capture driver exposes the scaler and
> composing functionality of the video capture IP.
> The previously existing functionality is entirely retained.
>
> I have introduced a few changes comparing to the last version
(v3) sent
> to the ML, as commented below.
>
> Sylwester Nawrocki (28):
> s5p-fimc: Add support for runtime PM in the mem-to-mem
driver
> s5p-fimc: Add media entity initialization
> s5p-fimc: Remove registration of video nodes from probe()
That patch seems weird for me. If they aren't registered at probe,
when they're registered?
They are registered in the media device probe callback, please see
fimc-mdevice.c, fimc_md_probe(). After all the modules they depend on
were initialized and registered.
This is needed to assure proper initialization sequence.
I also needed media device instance at hand when registering a video
node.
> s5p-fimc: Remove sclk_cam clock handling
> s5p-fimc: Limit number of available inputs to one
Camera sensors at FIMC input are no longer selected with S_INPUT
ioctl.
They will be attached to required FIMC entity through pipeline
re-configuration at the media device level.
Why? The proper way to select an input is via S_INPUT. The driver
may also
optionally allow changing it via the media device, but it should
not be
a mandatory requirement, as the media device API is optional.
The problem I'm trying to solve here is sharing the sensors and
mipi-csi receivers between multiple FIMC H/W instances. Previously
the driver supported attaching a sensor to only one selected FIMC at
compile time. You could, for instance, specify all sensors as the
selected FIMC's platform data and then use S_INPUT to choose between
them. The sensor could not be used together with any other FIMC. But
this is desired due to different capabilities of the FIMC IP
instances. And now, instead of hardcoding a sensor assigment to
particular video node, the sensors are bound to the media device. The
media device driver takes the list of sensors and attaches them one
by one to subsequent FIMC instances when it is initializing. Each
sensor has a link to each FIMC but only one of them is active by
default. That said an user application can use selected camera by
opening corresponding video node. Which camera is at which node can
be queried with G_INPUT.
I could try to implement the previous S_INPUT behaviour, but IMHO
this would lead to considerable and unnecessary driver code
complication due to supporting overlapping APIs.
--
Regards,
Sylwester
--
To unsubscribe from this list: send the line "unsubscribe linux-media" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
