media: tegra-video: Add support for V4L2_EVENT_SOURCE_CHANGE

Current implementation uses v4l2_ctrl_subscribe_event() and this
does not handle V4L2_EVENT_SOURCE_CHANGE.

So, update driver to handle V4L2_EVENT_SOURCE_CHANGE.
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

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

@@ -642,6 +642,18 @@ static int tegra_channel_set_subdev_active_fmt(struct tegra_vi_channel *chan)
 	return 0;
 }
 
+static int
+tegra_channel_subscribe_event(struct v4l2_fh *fh,
+			      const struct v4l2_event_subscription *sub)
+{
+	switch (sub->type) {
+	case V4L2_EVENT_SOURCE_CHANGE:
+		return v4l2_event_subscribe(fh, sub, 4, NULL);
+	}
+
+	return v4l2_ctrl_subscribe_event(fh, sub);
+}
+
 static int tegra_channel_g_selection(struct file *file, void *priv,
 				     struct v4l2_selection *sel)
 {
@@ -904,7 +916,7 @@ static const struct v4l2_ioctl_ops tegra_channel_ioctl_ops = {
 	.vidioc_expbuf			= vb2_ioctl_expbuf,
 	.vidioc_streamon		= vb2_ioctl_streamon,
 	.vidioc_streamoff		= vb2_ioctl_streamoff,
-	.vidioc_subscribe_event		= v4l2_ctrl_subscribe_event,
+	.vidioc_subscribe_event		= tegra_channel_subscribe_event,
 	.vidioc_unsubscribe_event	= v4l2_event_unsubscribe,
 	.vidioc_g_selection		= tegra_channel_g_selection,
 	.vidioc_s_selection		= tegra_channel_s_selection,