Hi,
On Wed, Jun 17, 2020 at 11:18:24AM +0900, JaeHun Jung wrote:
> In mobile, a co-processor is used when using USB audio
> to improve power consumption.
> hooking is required for sync-up when operating
> the co-processor. So register call-back function.
> The main operation of the call-back function is as follows:
> - Initialize the co-processor by transmitting data
> when initializing.
> - Change the co-processor setting value through
> the interface function.
> - Configure sampling rate
> - pcm open/close
>
> Bug: 156315379
>
> Change-Id: I32e1dd408e64aaef68ee06c480c4b4d4c95546dc
> Signed-off-by: JaeHun Jung <jh0801.jung@xxxxxxxxxxx>
> ---
> sound/usb/card.c | 16 ++++++++++++++++
> sound/usb/card.h | 1 +
> sound/usb/clock.c | 5 +++++
> sound/usb/pcm.c | 33 +++++++++++++++++++++++++++++++++
> sound/usb/usbaudio.h | 30 ++++++++++++++++++++++++++++++
> 5 files changed, 85 insertions(+)
> diff --git a/sound/usb/card.c b/sound/usb/card.c
> index fd6fd17..2f3fa14 100644
> --- a/sound/usb/card.c
> +++ b/sound/usb/card.c
> @@ -111,6 +111,7 @@ MODULE_PARM_DESC(skip_validation, "Skip unit descriptor validation (default: no)
> static DEFINE_MUTEX(register_mutex);
> static struct snd_usb_audio *usb_chip[SNDRV_CARDS];
> static struct usb_driver usb_audio_driver;
> +struct snd_usb_audio_vendor_ops *usb_audio_ops;
>
> /*
> * disconnect streams
> @@ -210,6 +211,12 @@ static int snd_usb_create_stream(struct snd_usb_audio *chip, int ctrlif, int int
> return 0;
> }
>
> +void snd_set_vender_interface(struct snd_usb_audio_vendor_ops *vendor_ops)
> +{
> + usb_audio_ops = vendor_ops;
> +}
> +EXPORT_SYMBOL_GPL(snd_set_vender_interface);
I think the symbol name has typo; 'vender' against 'vendor'.
Anyway, this feature is not widely used at present. I suggest to add
kernel configuration for the feature at kernel compilation time, IMO.
Regards
Takashi Sakamoto
