diff options
Diffstat (limited to 'include/media')
| -rw-r--r-- | include/media/v4l2-subdev.h | 21 |
1 files changed, 20 insertions, 1 deletions
diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h index 5459bcf5a423..a6a9e54388e2 100644 --- a/include/media/v4l2-subdev.h +++ b/include/media/v4l2-subdev.h @@ -215,7 +215,10 @@ struct v4l2_subdev_core_ops { * struct v4l2_subdev_tuner_ops - Callbacks used when v4l device was opened * in radio mode. * - * @s_radio: callback for VIDIOC_S_RADIO() ioctl handler code. + * @s_radio: callback that switches the tuner to radio mode. + * drivers should explicitly call it when a tuner ops should + * operate on radio mode, before being able to handle it. + * Used on devices that have both AM/FM radio receiver and TV. * * @s_frequency: callback for VIDIOC_S_FREQUENCY() ioctl handler code. * @@ -238,6 +241,22 @@ struct v4l2_subdev_core_ops { * @s_type_addr: sets tuner type and its I2C addr. * * @s_config: sets tda9887 specific stuff, like port1, port2 and qss + * + * .. note:: + * + * On devices that have both AM/FM and TV, it is up to the driver + * to explicitly call s_radio when the tuner should be switched to + * radio mode, before handling other &struct v4l2_subdev_tuner_ops + * that would require it. An example of such usage is:: + * + * static void s_frequency(void *priv, const struct v4l2_frequency *f) + * { + * ... + * if (f.type == V4L2_TUNER_RADIO) + * v4l2_device_call_all(v4l2_dev, 0, tuner, s_radio); + * ... + * v4l2_device_call_all(v4l2_dev, 0, tuner, s_frequency); + * } */ struct v4l2_subdev_tuner_ops { int (*s_radio)(struct v4l2_subdev *sd); |