Re: [PATCH v3 11/14] media: platform: pxa_camera: make a standalone v4l2 device

From: Hans Verkuil
Date: Sun Aug 14 2016 - 05:25:49 EST


On 08/08/2016 09:30 PM, Robert Jarzmik wrote:

<snip>

> +static int pxa_camera_sensor_bound(struct v4l2_async_notifier *notifier,
> + struct v4l2_subdev *subdev,
> + struct v4l2_async_subdev *asd)
> +{
> + int err;
> + struct v4l2_device *v4l2_dev = notifier->v4l2_dev;
> + struct pxa_camera_dev *pcdev = v4l2_dev_to_pcdev(v4l2_dev);
> + struct video_device *vdev = &pcdev->vdev;
> + struct v4l2_pix_format *pix = &pcdev->current_pix;
> + struct v4l2_subdev_format format = {
> + .which = V4L2_SUBDEV_FORMAT_ACTIVE,
> + };
> + struct v4l2_mbus_framefmt *mf = &format.format;
> +
> + dev_info(pcdev_to_dev(pcdev), "%s(): trying to bind a device\n",
> + __func__);
> + mutex_lock(&pcdev->mlock);
> + *vdev = pxa_camera_videodev_template;
> + vdev->v4l2_dev = v4l2_dev;
> + vdev->lock = &pcdev->mlock;
> + pcdev->sensor = subdev;
> + pcdev->vdev.queue = &pcdev->vb2_vq;
> + pcdev->vdev.v4l2_dev = &pcdev->v4l2_dev;

You're missing this line here:

pcdev->vdev.ctrl_handler = subdev->ctrl_handler;

This ensures that the sensor's controls are exposed to the video device node.

> + video_set_drvdata(&pcdev->vdev, pcdev);
> +
> + v4l2_disable_ioctl(vdev, VIDIOC_G_STD);
> + v4l2_disable_ioctl(vdev, VIDIOC_S_STD);

Since you don't implement vidioc_g/s_std these two lines can be removed.

> +
> + err = pxa_camera_build_formats(pcdev);
> + if (err) {
> + dev_err(pcdev_to_dev(pcdev), "building formats failed: %d\n",
> + err);
> + goto out;
> + }
> +
> + pcdev->current_fmt = pcdev->user_formats;
> + pix->field = V4L2_FIELD_NONE;
> + pix->width = DEFAULT_WIDTH;
> + pix->height = DEFAULT_HEIGHT;
> + pix->bytesperline =
> + soc_mbus_bytes_per_line(pix->width,
> + pcdev->current_fmt->host_fmt);
> + pix->sizeimage =
> + soc_mbus_image_size(pcdev->current_fmt->host_fmt,
> + pix->bytesperline, pix->height);
> + pix->pixelformat = pcdev->current_fmt->host_fmt->fourcc;
> + v4l2_fill_mbus_format(mf, pix, pcdev->current_fmt->code);
> + err = sensor_call(pcdev, pad, set_fmt, NULL, &format);
> + if (err)
> + goto out;
> +
> + v4l2_fill_pix_format(pix, mf);
> + pr_info("%s(): colorspace=0x%x pixfmt=0x%x\n",
> + __func__, pix->colorspace, pix->pixelformat);
> +
> + err = pxa_camera_init_videobuf2(pcdev);
> + if (err)
> + goto out;
> +
> + err = video_register_device(&pcdev->vdev, VFL_TYPE_GRABBER, -1);
> + if (err) {
> + v4l2_err(v4l2_dev, "register video device failed: %d\n", err);
> + pcdev->sensor = NULL;
> + } else {
> + dev_info(pcdev_to_dev(pcdev),
> + "PXA Camera driver attached to camera %s\n",
> + subdev->name);
> + subdev->owner = v4l2_dev->dev->driver->owner;
> + }
> +out:
> + mutex_unlock(&pcdev->mlock);
> + return err;
> +}

Regards,

Hans