struct v4l2_subdev_audio_ops — Callbacks used for audio-related settings
struct v4l2_subdev_audio_ops {
int (* s_clock_freq) (struct v4l2_subdev *sd, u32 freq);
int (* s_i2s_clock_freq) (struct v4l2_subdev *sd, u32 freq);
int (* s_routing) (struct v4l2_subdev *sd, u32 input, u32 output, u32 config);
int (* s_stream) (struct v4l2_subdev *sd, int enable);
}; set the frequency (in Hz) of the audio clock output. Used to slave an audio processor to the video decoder, ensuring that audio and video remain synchronized. Usual values for the frequency are 48000, 44100 or 32000 Hz. If the frequency is not supported, then -EINVAL is returned.
sets I2S speed in bps. This is used to provide a standard way to select I2S clock used by driving digital audio streams at some board designs. Usual values for the frequency are 1024000 and 2048000. If the frequency is not supported, then -EINVAL is returned.
used to define the input and/or output pins of an audio chip, and any additional configuration data. Never attempt to use user-level input IDs (e.g. Composite, S-Video, Tuner) at this level. An i2c device shouldn't know about whether an input pin is connected to a Composite connector, become on another board or platform it might be connected to something else entirely. The calling driver is responsible for mapping a user-level input to the right pins on the i2c device.
used to notify the audio code that stream will start or has stopped.