github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-05-24 15:12:13 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

ALSA: usb-audio: Check for support for requested audio format

Browse Source 
Allow for checks on a specific USB audio device to see if a requested PCM
format is supported.  This is needed for support when playback is
initiated by the ASoC USB backend path.

Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Wesley Cheng <quic_wcheng@quicinc.com>
Acked-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20250409194804.3773260-10-quic_wcheng@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Wesley Cheng 2025-04-09 12:47:42 -07:00 committed by Greg Kroah-Hartman
parent 5a49a6ba22
commit 2bde439265
2 changed files with 35 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

32
sound/usb/card.c
View File

@ -119,6 +119,38 @@ static DEFINE_MUTEX(register_mutex);
static struct snd_usb_audio *usb_chip[SNDRV_CARDS];
static struct usb_driver usb_audio_driver;
/*
* Checks to see if requested audio profile, i.e sample rate, # of
* channels, etc... is supported by the substream associated to the
* USB audio device.
*/
struct snd_usb_stream *
snd_usb_find_suppported_substream(int card_idx, struct snd_pcm_hw_params *params,
int direction)
{
struct snd_usb_audio *chip;
struct snd_usb_substream *subs;
struct snd_usb_stream *as;
/*
* Register mutex is held when populating and clearing usb_chip
* array.
*/
guard(mutex)(&register_mutex);
chip = usb_chip[card_idx];
if (chip && enable[card_idx]) {
list_for_each_entry(as, &chip->pcm_list, list) {
subs = &as->substream[direction];
if (snd_usb_find_substream_format(subs, params))
return as;
}
}
return NULL;
}
EXPORT_SYMBOL_GPL(snd_usb_find_suppported_substream);
/*
* disconnect streams
* called from usb_audio_disconnect()

3
sound/usb/card.h
View File

@ -207,4 +207,7 @@ struct snd_usb_stream {
struct list_head list;
};
struct snd_usb_stream *
snd_usb_find_suppported_substream(int card_idx, struct snd_pcm_hw_params *params,
int direction);
#endif /* __USBAUDIO_CARD_H */