Re: [PATCH v20 22/41] ASoC: usb: Add PCM format check API for USB backend

On 4/25/2024 11:51 PM, Wesley Cheng wrote:

Introduce a helper to check if a particular PCM format is supported by the USB audio device connected. If the USB audio device does not have an audio profile which can support the requested format, then notify the USB backend.

Signed-off-by: Wesley Cheng quic_wcheng@quicinc.com

(...)

+/**

• • snd_soc_usb_find_format() - Check if audio format is supported
• • @card_idx: USB sound chip array index
• • @params: PCM parameters
• • @direction: capture or playback
• • Ensure that a requested audio profile from the ASoC side is able to be
• • supported by the USB device.
• • Return 0 on success, negative on error.
• */

+int snd_soc_usb_find_format(int card_idx, struct snd_pcm_hw_params *params,

• 	int direction)
  

Perhaps name function similar to its snd_usb equivalent, so snd_soc_usb_find_supported_format?

+{

• struct snd_usb_stream *as;
• as = snd_usb_find_suppported_substream(card_idx, params, direction);
• if (!as)

• return -EOPNOTSUPP;
  

• return 0;

+} +EXPORT_SYMBOL_GPL(snd_soc_usb_find_format);

• /**
  • snd_soc_usb_allocate_port() - allocate a SOC USB device
  • @component: USB DPCM backend DAI component