[RFC,v2,12/18] media: tegra-video: Add support for selection ioctl ops

This patch adds selection v4l2 ioctl operations to allow configuring
a selection rectangle in the sensor through the Tegra video device
node.

Some sensor drivers supporting crop uses try_crop rectangle from
v4l2_subdev_pad_config during try format for computing binning.

So with selection ops support, this patch also updates try format
to use try crop rectangle either from subdev frame size enumeration
or from subdev crop boundary.

Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
---
 drivers/staging/media/tegra-video/vi.c | 106 +++++++++++++++++++++++++++++++++
 1 file changed, 106 insertions(+)

On 02/07/2020 23:20, Sowjanya Komatineni wrote:
> 

> On 7/2/20 6:54 AM, Hans Verkuil wrote:

>> On 17/06/2020 03:41, Sowjanya Komatineni wrote:

>>> This patch adds selection v4l2 ioctl operations to allow configuring

>>> a selection rectangle in the sensor through the Tegra video device

>>> node.

>>>

>>> Some sensor drivers supporting crop uses try_crop rectangle from

>>> v4l2_subdev_pad_config during try format for computing binning.

>>>

>>> So with selection ops support, this patch also updates try format

>>> to use try crop rectangle either from subdev frame size enumeration

>>> or from subdev crop boundary.

>>>

>>> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>

>>> ---

>>>   drivers/staging/media/tegra-video/vi.c | 106 +++++++++++++++++++++++++++++++++

>>>   1 file changed, 106 insertions(+)

>>>

>>> diff --git a/drivers/staging/media/tegra-video/vi.c b/drivers/staging/media/tegra-video/vi.c

>>> index 506c263..f9eb96b 100644

>>> --- a/drivers/staging/media/tegra-video/vi.c

>>> +++ b/drivers/staging/media/tegra-video/vi.c

>>> @@ -427,6 +427,13 @@ static int __tegra_channel_try_format(struct tegra_vi_channel *chan,

>>>   	struct v4l2_subdev *subdev;

>>>   	struct v4l2_subdev_format fmt;

>>>   	struct v4l2_subdev_pad_config *pad_cfg;

>>> +	struct v4l2_subdev_frame_size_enum fse = {

>>> +		.which = V4L2_SUBDEV_FORMAT_TRY,

>>> +	};

>>> +	struct v4l2_subdev_selection sdsel = {

>>> +		.which = V4L2_SUBDEV_FORMAT_ACTIVE,

>>> +		.target = V4L2_SEL_TGT_CROP_BOUNDS,

>>> +	};

>>>   	int ret;

>>>   

>>>   	subdev = tegra_channel_get_remote_subdev(chan, true);

>>> @@ -449,6 +456,24 @@ static int __tegra_channel_try_format(struct tegra_vi_channel *chan,

>>>   	fmt.which = V4L2_SUBDEV_FORMAT_TRY;

>>>   	fmt.pad = 0;

>>>   	v4l2_fill_mbus_format(&fmt.format, pix, fmtinfo->code);

>>> +

>>> +	/*

>>> +	 * Attempt to obtain the format size from subdev.

>>> +	 * If not available, try to get crop boundary from subdev.

>>> +	 */

>>> +	fse.code = fmtinfo->code;

>>> +	ret = v4l2_subdev_call(subdev, pad, enum_frame_size, pad_cfg, &fse);

>>> +	if (ret) {

>>> +		ret = v4l2_subdev_call(subdev, pad, get_selection, NULL, &sdsel);

>>> +		if (ret)

>>> +			return -EINVAL;

>>> +		pad_cfg->try_crop.width = sdsel.r.width;

>>> +		pad_cfg->try_crop.height = sdsel.r.height;

>>> +	} else {

>>> +		pad_cfg->try_crop.width = fse.max_width;

>>> +		pad_cfg->try_crop.height = fse.max_height;

>>> +	}

>>> +

>>>   	ret = v4l2_subdev_call(subdev, pad, set_fmt, pad_cfg, &fmt);

>>>   	if (ret < 0)

>>>   		return ret;

>>> @@ -540,6 +565,85 @@ static int tegra_channel_set_subdev_active_fmt(struct tegra_vi_channel *chan)

>>>   	return 0;

>>>   }

>>>   

>>> +static int tegra_channel_g_selection(struct file *file, void *priv,

>>> +				     struct v4l2_selection *sel)

>>> +{

>>> +	struct tegra_vi_channel *chan = video_drvdata(file);

>>> +	struct v4l2_subdev *subdev;

>>> +	struct v4l2_subdev_format fmt = {

>>> +		.which = V4L2_SUBDEV_FORMAT_ACTIVE,

>>> +	};

>>> +	struct v4l2_subdev_selection sdsel = {

>>> +		.which = V4L2_SUBDEV_FORMAT_ACTIVE,

>>> +		.target = sel->target,

>>> +	};

>>> +	int ret;

>>> +

>>> +	if (IS_ENABLED(CONFIG_VIDEO_TEGRA_TPG))

>>> +		return -ENOTTY;

>>> +

>>> +	if (sel->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)

>>> +		return -EINVAL;

>>> +	/*

>>> +	 * Try the get selection operation and fallback to get format if not

>>> +	 * implemented.

>>> +	 */

>>> +	subdev = tegra_channel_get_remote_subdev(chan, true);

>>> +	ret = v4l2_subdev_call(subdev, pad, get_selection, NULL, &sdsel);

>>> +	if (!ret)

>>> +		sel->r = sdsel.r;

>>> +	if (ret != -ENOIOCTLCMD)

>>> +		return ret;

>>> +

>>> +	ret = v4l2_subdev_call(subdev, pad, get_fmt, NULL, &fmt);

>>> +	if (ret < 0)

>>> +		return ret;

>>> +

>>> +	sel->r.left = 0;

>>> +	sel->r.top = 0;

>>> +	sel->r.width = fmt.format.width;

>>> +	sel->r.height = fmt.format.height;

>>> +

>>> +	return 0;

>>> +}

>>> +

>>> +static int tegra_channel_s_selection(struct file *file, void *fh,

>>> +				     struct v4l2_selection *sel)

>>> +{

>>> +	struct tegra_vi_channel *chan = video_drvdata(file);

>>> +	struct v4l2_subdev *subdev;

>>> +	int ret;

>>> +	struct v4l2_subdev_selection sdsel = {

>>> +		.which = V4L2_SUBDEV_FORMAT_ACTIVE,

>>> +		.target = sel->target,

>>> +		.flags = sel->flags,

>>> +		.r = sel->r,

>>> +	};

>>> +

>> This function doesn't check if the subdev actually supports set_selection.

>> The imx219 is one such driver: it supports get_selection, but not set_selection.

>>

>> So this code should add these lines to fix the v4l2-compliance fail:

>>

>>         subdev = tegra_channel_get_remote_subdev(chan, true);

>>

>>         if (!v4l2_subdev_has_op(subdev, pad, set_selection))

>>                 return -ENOTTY;

>>

> v4l2_subdev_call() does that check and returns -ENOIOCTLCMD when 

> specified subdev ops does not exist.


But that test happens too late. In the v4l2-compliance test it fails in the
sel->type test below, so it returns EINVAL instead of ENOTTY.

>>> +	if (IS_ENABLED(CONFIG_VIDEO_TEGRA_TPG))

>>> +		return -ENOTTY;


I think this test should come before the v4l2_subdev_has_op test since there
is probably no subdev if the TPG is enabled. So:

	if (IS_ENABLED(CONFIG_VIDEO_TEGRA_TPG))
		return -ENOTTY;

        subdev = tegra_channel_get_remote_subdev(chan, true);
        if (!v4l2_subdev_has_op(subdev, pad, set_selection))
                return -ENOTTY;


Regards,

	Hans

>>> +

>>> +	if (sel->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)

>>> +		return -EINVAL;

>>> +

>>> +	if (vb2_is_busy(&chan->queue))

>>> +		return -EBUSY;

>>> +

>>> +	subdev = tegra_channel_get_remote_subdev(chan, true);

>> And this line can be dropped.

>>

>> Regards,

>>

>> 	Hans

>>

>>> +	ret = v4l2_subdev_call(subdev, pad, set_selection, NULL, &sdsel);

>>> +	if (!ret) {

>>> +		sel->r = sdsel.r;

>>> +		/*

>>> +		 * Subdev active format resolution may have changed during

>>> +		 * set selection operation. So, update channel format to

>>> +		 * the sub-device active format.

>>> +		 */

>>> +		return tegra_channel_set_subdev_active_fmt(chan);

>>> +	}

>>> +

>>> +	return ret;

>>> +}

>>> +

>>>   static int tegra_channel_enum_input(struct file *file, void *fh,

>>>   				    struct v4l2_input *inp)

>>>   {

>>> @@ -597,6 +701,8 @@ static const struct v4l2_ioctl_ops tegra_channel_ioctl_ops = {

>>>   	.vidioc_streamoff		= vb2_ioctl_streamoff,

>>>   	.vidioc_subscribe_event		= v4l2_ctrl_subscribe_event,

>>>   	.vidioc_unsubscribe_event	= v4l2_event_unsubscribe,

>>> +	.vidioc_g_selection		= tegra_channel_g_selection,

>>> +	.vidioc_s_selection		= tegra_channel_s_selection,

>>>   };

>>>   

>>>   /*

>>>