[media] tuner-core/v4l2-subdev: document that the type field has to be filled in

The tuner ops g_frequency, g_tuner and s_tuner require that the tuner type
field is filled in. Document this.

The tuner-core doc is based on a patch from Mauro Carvalho Chehab <mchehab@redhat.com>.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
index 224502067c43..2884e3e69cb1 100644
--- a/include/media/v4l2-subdev.h
+++ b/include/media/v4l2-subdev.h
@@ -175,6 +175,13 @@ struct v4l2_subdev_core_ops {
 
 /* s_radio: v4l device was opened in radio mode.
 
+   g_frequency: freq->type must be filled in. Normally done by video_ioctl2
+        or the bridge driver.
+
+   g_tuner:
+   s_tuner: vt->type must be filled in. Normally done by video_ioctl2 or the
+        bridge driver.
+
    s_type_addr: sets tuner type and its I2C addr.
 
    s_config: sets tda9887 specific stuff, like port1, port2 and qss