> +static inline int snd_soc_usb_setup_offload_jack(struct snd_soc_component *component,
> + struct snd_soc_jack *jack)
> +{
> + return -ENODEV;
> +}
> +
> +static inline int snd_soc_usb_disable_offload_jack(struct snd_soc_component *component)
> +{
> + return -ENODEV;
> +}
usually fallback functions return 0, is the error code intentional?
> +int snd_soc_usb_setup_offload_jack(struct snd_soc_component *component,
> + struct snd_soc_jack *jack)
> +{
> + int ret;
> +
> + ret = snd_soc_card_jack_new(component->card, "USB Offload Playback Jack",
do we need the reference to Playback?
> + SND_JACK_HEADPHONE, jack);
wondering if there would be any merit in defining a new type of jack,
e.g. SND_JACK_USB since here the purpose is to notify that there's a USB
device connected. The type of device does not really matter, does it?
> + if (ret < 0) {
> + dev_err(component->card->dev, "Unable to add USB offload jack\n");
> + return ret;
> + }
> +
> + ret = snd_soc_component_set_jack(component, jack, NULL);
> + if (ret) {
> + dev_err(component->card->dev, "Failed to set jack: %d\n", ret);
> + return ret;
> + }
> +
> + return 0;
