[media] adv7842: add support to for the content type control

This receiver now supports reading the IT content type of the incoming
video.

Signed-off-by: Hans Verkuil <[e-mail]>
Signed-off-by: Mauro Carvalho Chehab <[e-mail]>

drivers/media/i2c/adv7842.c

···
 	return -EINVAL;
 }
 
+static int adv7842_g_volatile_ctrl(struct v4l2_ctrl *ctrl)
+{
+	struct v4l2_subdev *sd = to_sd(ctrl);
+
+	if (ctrl->id == V4L2_CID_DV_RX_IT_CONTENT_TYPE) {
+		ctrl->val = V4L2_DV_IT_CONTENT_TYPE_NO_ITC;
+		if ((io_read(sd, 0x60) & 1) && (infoframe_read(sd, 0x03) & 0x80))
+			ctrl->val = (infoframe_read(sd, 0x05) >> 4) & 3;
+		return 0;
+	}
+	return -EINVAL;
+}
+
 static inline bool no_power(struct v4l2_subdev *sd)
 {
 	return io_read(sd, 0x0c) & 0x24;
···
 
 static const struct v4l2_ctrl_ops adv7842_ctrl_ops = {
 	.s_ctrl = adv7842_s_ctrl,
+	.g_volatile_ctrl = adv7842_g_volatile_ctrl,
 };
 
 static const struct v4l2_subdev_core_ops adv7842_core_ops = {
···
 		V4L2_DV_BT_CEA_640X480P59_94;
 	struct adv7842_platform_data *pdata = client->dev.platform_data;
 	struct v4l2_ctrl_handler *hdl;
+	struct v4l2_ctrl *ctrl;
 	struct v4l2_subdev *sd;
 	u16 rev;
 	int err;
···
 			  V4L2_CID_SATURATION, 0, 255, 1, 128);
 	v4l2_ctrl_new_std(hdl, &adv7842_ctrl_ops,
 			  V4L2_CID_HUE, 0, 128, 1, 0);
+	ctrl = v4l2_ctrl_new_std_menu(hdl, &adv7842_ctrl_ops,
+			V4L2_CID_DV_RX_IT_CONTENT_TYPE, V4L2_DV_IT_CONTENT_TYPE_NO_ITC,
+			0, V4L2_DV_IT_CONTENT_TYPE_NO_ITC);
+	if (ctrl)
+		ctrl->flags |= V4L2_CTRL_FLAG_VOLATILE;
 
 	/* custom controls */
 	state->detect_tx_5v_ctrl = v4l2_ctrl_new_std(hdl, NULL,