Re: [PATCH 01/11] rcar-vin: Refactor controls creation for video device

["Niklas Söderlund" <niklas.soderlund+renesas@ragnatech.se>]

Hello :-)

On 2021-07-06 18:08:42 +0200, Jacopo Mondi wrote:
> Hi again,
> 
> On Tue, Apr 13, 2021 at 08:02:43PM +0200, Niklas Söderlund wrote:
> > The controls for the video device are created in different code paths
> > depending on if the driver is using the media graph centric model (Gen3)
> > or the device centric model (Gen2 and earlier). This have lead to code
> > duplication that can be consolidated.
> >
> > Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> > ---
> >  drivers/media/platform/rcar-vin/rcar-core.c | 82 +++++++++++----------
> >  1 file changed, 45 insertions(+), 37 deletions(-)
> >
> > diff --git a/drivers/media/platform/rcar-vin/rcar-core.c b/drivers/media/platform/rcar-vin/rcar-core.c
> > index cb3025992817d625..c798dc9409e4cdcd 100644
> > --- a/drivers/media/platform/rcar-vin/rcar-core.c
> > +++ b/drivers/media/platform/rcar-vin/rcar-core.c
> > @@ -405,6 +405,45 @@ static const struct v4l2_ctrl_ops rvin_ctrl_ops = {
> >  	.s_ctrl = rvin_s_ctrl,
> >  };
> >
> > +static void rvin_free_controls(struct rvin_dev *vin)
> > +{
> > +	v4l2_ctrl_handler_free(&vin->ctrl_handler);
> > +	vin->vdev.ctrl_handler = NULL;
> > +}
> > +
> > +static int rvin_create_controls(struct rvin_dev *vin, struct v4l2_subdev *subdev)
> > +{
> > +	int ret;
> > +
> > +	ret = v4l2_ctrl_handler_init(&vin->ctrl_handler, 16);
> 
> Not a big deal, but 16 because we have to reserve space for the
> eventual subdevice controls ?

Yes, again for Gen2 where the controls of the subdevice are exposed on 
the video device. IIRC the number 16 comes from the soc-camera ancestor 
for this driver.

> 
> > +	if (ret < 0)
> > +		return ret;
> > +
> > +	/* The VIN directly deals with alpha component. */
> > +	v4l2_ctrl_new_std(&vin->ctrl_handler, &rvin_ctrl_ops,
> > +			  V4L2_CID_ALPHA_COMPONENT, 0, 255, 1, 255);
> > +
> > +	if (vin->ctrl_handler.error) {
> > +		ret = vin->ctrl_handler.error;
> > +		rvin_free_controls(vin);
> > +		return ret;
> > +	}
> > +
> > +	/* For the non-MC mode add controls from the subdevice. */
> > +	if (subdev) {
> > +		ret = v4l2_ctrl_add_handler(&vin->ctrl_handler,
> > +					    subdev->ctrl_handler, NULL, true);
> > +		if (ret < 0) {
> > +			rvin_free_controls(vin);
> > +			return ret;
> > +		}
> > +	}
> > +
> > +	vin->vdev.ctrl_handler = &vin->ctrl_handler;
> > +
> > +	return 0;
> > +}
> > +
> >  /* -----------------------------------------------------------------------------
> >   * Async notifier
> >   */
> > @@ -490,28 +529,10 @@ static int rvin_parallel_subdevice_attach(struct rvin_dev *vin,
> >  		return ret;
> >
> >  	/* Add the controls */
> > -	ret = v4l2_ctrl_handler_init(&vin->ctrl_handler, 16);
> > +	ret = rvin_create_controls(vin, subdev);
> >  	if (ret < 0)
> >  		return ret;
> >
> > -	v4l2_ctrl_new_std(&vin->ctrl_handler, &rvin_ctrl_ops,
> > -			  V4L2_CID_ALPHA_COMPONENT, 0, 255, 1, 255);
> > -
> > -	if (vin->ctrl_handler.error) {
> > -		ret = vin->ctrl_handler.error;
> > -		v4l2_ctrl_handler_free(&vin->ctrl_handler);
> > -		return ret;
> > -	}
> > -
> > -	ret = v4l2_ctrl_add_handler(&vin->ctrl_handler, subdev->ctrl_handler,
> > -				    NULL, true);
> > -	if (ret < 0) {
> > -		v4l2_ctrl_handler_free(&vin->ctrl_handler);
> > -		return ret;
> > -	}
> > -
> > -	vin->vdev.ctrl_handler = &vin->ctrl_handler;
> > -
> >  	vin->parallel.subdev = subdev;
> >
> >  	return 0;
> > @@ -522,10 +543,8 @@ static void rvin_parallel_subdevice_detach(struct rvin_dev *vin)
> >  	rvin_v4l2_unregister(vin);
> >  	vin->parallel.subdev = NULL;
> >
> > -	if (!vin->info->use_mc) {
> > -		v4l2_ctrl_handler_free(&vin->ctrl_handler);
> > -		vin->vdev.ctrl_handler = NULL;
> > -	}
> > +	if (!vin->info->use_mc)
> > +		rvin_free_controls(vin);
> >  }
> >
> >  static int rvin_parallel_notify_complete(struct v4l2_async_notifier *notifier)
> > @@ -935,21 +954,10 @@ static int rvin_mc_init(struct rvin_dev *vin)
> >  	if (ret)
> >  		rvin_group_put(vin);
> >
> > -	ret = v4l2_ctrl_handler_init(&vin->ctrl_handler, 1);
> > +	ret = rvin_create_controls(vin, NULL);
> >  	if (ret < 0)
> >  		return ret;
> >
> > -	v4l2_ctrl_new_std(&vin->ctrl_handler, &rvin_ctrl_ops,
> > -			  V4L2_CID_ALPHA_COMPONENT, 0, 255, 1, 255);
> > -
> > -	if (vin->ctrl_handler.error) {
> > -		ret = vin->ctrl_handler.error;
> > -		v4l2_ctrl_handler_free(&vin->ctrl_handler);
> > -		return ret;
> > -	}
> > -
> > -	vin->vdev.ctrl_handler = &vin->ctrl_handler;
> > -
> >  	return ret;
> >  }
> >
> > @@ -1446,7 +1454,7 @@ static int rcar_vin_probe(struct platform_device *pdev)
> >  	return 0;
> >
> >  error_group_unregister:
> > -	v4l2_ctrl_handler_free(&vin->ctrl_handler);
> > +	rvin_free_controls(vin);
> >
> >  	if (vin->info->use_mc) {
> >  		mutex_lock(&vin->group->lock);
> > @@ -1481,7 +1489,7 @@ static int rcar_vin_remove(struct platform_device *pdev)
> >  		rvin_group_put(vin);
> >  	}
> >
> > -	v4l2_ctrl_handler_free(&vin->ctrl_handler);
> > +	rvin_free_controls(vin);
> >
> >  	rvin_dma_unregister(vin);
> >
> > --
> > 2.31.1
> >

-- 
Regards,
Niklas Söderlund