Commit 5a49a6ba authored by Wesley Cheng's avatar Wesley Cheng Committed by Greg Kroah-Hartman
Browse files

ALSA: usb-audio: Export USB SND APIs for modules 



Some vendor modules will utilize useful parsing and endpoint management
APIs to start audio playback/capture.

Reviewed-by: default avatarPierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Tested-by: default avatarPuma Hsu <pumahsu@google.com>
Tested-by: default avatarDaehwan Jung <dh10.jung@samsung.com>
Signed-off-by: default avatarWesley Cheng <quic_wcheng@quicinc.com>
Acked-by: default avatarMark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20250409194804.3773260-9-quic_wcheng@quicinc.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 67890d57

sound/usb/card.c

+4 −0
Original line number Diff line number Diff line
@@ -1030,6 +1030,7 @@ int snd_usb_lock_shutdown(struct snd_usb_audio *chip) 
		wake_up(&chip->shutdown_wait);

	return err;

}

EXPORT_SYMBOL_GPL(snd_usb_lock_shutdown);



/* autosuspend and unlock the shutdown */

void snd_usb_unlock_shutdown(struct snd_usb_audio *chip)
@@ -1038,6 +1039,7 @@ void snd_usb_unlock_shutdown(struct snd_usb_audio *chip) 
	if (atomic_dec_and_test(&chip->usage_count))

		wake_up(&chip->shutdown_wait);

}

EXPORT_SYMBOL_GPL(snd_usb_unlock_shutdown);



int snd_usb_autoresume(struct snd_usb_audio *chip)

{
@@ -1060,6 +1062,7 @@ int snd_usb_autoresume(struct snd_usb_audio *chip) 
	}

	return 0;

}

EXPORT_SYMBOL_GPL(snd_usb_autoresume);



void snd_usb_autosuspend(struct snd_usb_audio *chip)

{
@@ -1073,6 +1076,7 @@ void snd_usb_autosuspend(struct snd_usb_audio *chip) 
	for (i = 0; i < chip->num_interfaces; i++)

		usb_autopm_put_interface(chip->intf[i]);

}

EXPORT_SYMBOL_GPL(snd_usb_autosuspend);



static int usb_audio_suspend(struct usb_interface *intf, pm_message_t message)

{

sound/usb/endpoint.c

+1 −0
Original line number Diff line number Diff line
@@ -1524,6 +1524,7 @@ int snd_usb_endpoint_prepare(struct snd_usb_audio *chip, 
	mutex_unlock(&chip->mutex);

	return err;

}

EXPORT_SYMBOL_GPL(snd_usb_endpoint_prepare);



/* get the current rate set to the given clock by any endpoint */

int snd_usb_endpoint_get_clock_rate(struct snd_usb_audio *chip, int clock)

sound/usb/helper.c

+1 −0
Original line number Diff line number Diff line
@@ -62,6 +62,7 @@ void *snd_usb_find_csint_desc(void *buffer, int buflen, void *after, u8 dsubtype 
	}

	return NULL;

}

EXPORT_SYMBOL_GPL(snd_usb_find_csint_desc);



/*

 * Wrapper for usb_control_msg().

sound/usb/pcm.c

+54 −21
Original line number Diff line number Diff line
@@ -148,6 +148,16 @@ find_format(struct list_head *fmt_list_head, snd_pcm_format_t format, 
	return found;

}



const struct audioformat *

snd_usb_find_format(struct list_head *fmt_list_head, snd_pcm_format_t format,

		    unsigned int rate, unsigned int channels, bool strict_match,

		    struct snd_usb_substream *subs)

{

	return find_format(fmt_list_head, format, rate, channels, strict_match,

			subs);

}

EXPORT_SYMBOL_GPL(snd_usb_find_format);



static const struct audioformat *

find_substream_format(struct snd_usb_substream *subs,

		      const struct snd_pcm_hw_params *params)
@@ -157,6 +167,14 @@ find_substream_format(struct snd_usb_substream *subs, 
			   true, subs);

}



const struct audioformat *

snd_usb_find_substream_format(struct snd_usb_substream *subs,

			      const struct snd_pcm_hw_params *params)

{

	return find_substream_format(subs, params);

}

EXPORT_SYMBOL_GPL(snd_usb_find_substream_format);



bool snd_usb_pcm_has_fixed_rate(struct snd_usb_substream *subs)

{

	const struct audioformat *fp;
@@ -461,20 +479,9 @@ static void close_endpoints(struct snd_usb_audio *chip, 
	}

}



/*

 * hw_params callback

 *

 * allocate a buffer and set the given audio format.

 *

 * so far we use a physically linear buffer although packetize transfer

 * doesn't need a continuous area.

 * if sg buffer is supported on the later version of alsa, we'll follow

 * that.

 */

static int snd_usb_hw_params(struct snd_pcm_substream *substream,

int snd_usb_hw_params(struct snd_usb_substream *subs,

		      struct snd_pcm_hw_params *hw_params)

{

	struct snd_usb_substream *subs = substream->runtime->private_data;

	struct snd_usb_audio *chip = subs->stream->chip;

	const struct audioformat *fmt;

	const struct audioformat *sync_fmt;
@@ -499,7 +506,7 @@ static int snd_usb_hw_params(struct snd_pcm_substream *substream, 
	if (fmt->implicit_fb) {

		sync_fmt = snd_usb_find_implicit_fb_sync_format(chip, fmt,

								hw_params,

								!substream->stream,

								!subs->direction,

								&sync_fixed_rate);

		if (!sync_fmt) {

			usb_audio_dbg(chip,
@@ -579,15 +586,28 @@ static int snd_usb_hw_params(struct snd_pcm_substream *substream, 


	return ret;

}

EXPORT_SYMBOL_GPL(snd_usb_hw_params);



/*

 * hw_free callback

 * hw_params callback

 *

 * reset the audio format and release the buffer

 * allocate a buffer and set the given audio format.

 *

 * so far we use a physically linear buffer although packetize transfer

 * doesn't need a continuous area.

 * if sg buffer is supported on the later version of alsa, we'll follow

 * that.

 */

static int snd_usb_hw_free(struct snd_pcm_substream *substream)

static int snd_usb_pcm_hw_params(struct snd_pcm_substream *substream,

				 struct snd_pcm_hw_params *hw_params)

{

	struct snd_usb_substream *subs = substream->runtime->private_data;



	return snd_usb_hw_params(subs, hw_params);

}



int snd_usb_hw_free(struct snd_usb_substream *subs)

{

	struct snd_usb_audio *chip = subs->stream->chip;



	snd_media_stop_pipeline(subs);
@@ -603,6 +623,19 @@ static int snd_usb_hw_free(struct snd_pcm_substream *substream) 


	return 0;

}

EXPORT_SYMBOL_GPL(snd_usb_hw_free);



/*

 * hw_free callback

 *

 * reset the audio format and release the buffer

 */

static int snd_usb_pcm_hw_free(struct snd_pcm_substream *substream)

{

	struct snd_usb_substream *subs = substream->runtime->private_data;



	return snd_usb_hw_free(subs);

}



/* free-wheeling mode? (e.g. dmix) */

static int in_free_wheeling_mode(struct snd_pcm_runtime *runtime)
@@ -1746,8 +1779,8 @@ static int snd_usb_substream_capture_trigger(struct snd_pcm_substream *substream 
static const struct snd_pcm_ops snd_usb_playback_ops = {

	.open =		snd_usb_pcm_open,

	.close =	snd_usb_pcm_close,

	.hw_params =	snd_usb_hw_params,

	.hw_free =	snd_usb_hw_free,

	.hw_params =	snd_usb_pcm_hw_params,

	.hw_free =	snd_usb_pcm_hw_free,

	.prepare =	snd_usb_pcm_prepare,

	.trigger =	snd_usb_substream_playback_trigger,

	.sync_stop =	snd_usb_pcm_sync_stop,
@@ -1758,8 +1791,8 @@ static const struct snd_pcm_ops snd_usb_playback_ops = { 
static const struct snd_pcm_ops snd_usb_capture_ops = {

	.open =		snd_usb_pcm_open,

	.close =	snd_usb_pcm_close,

	.hw_params =	snd_usb_hw_params,

	.hw_free =	snd_usb_hw_free,

	.hw_params =	snd_usb_pcm_hw_params,

	.hw_free =	snd_usb_pcm_hw_free,

	.prepare =	snd_usb_pcm_prepare,

	.trigger =	snd_usb_substream_capture_trigger,

	.sync_stop =	snd_usb_pcm_sync_stop,

sound/usb/pcm.h

+11 −0
Original line number Diff line number Diff line
@@ -15,4 +15,15 @@ void snd_usb_preallocate_buffer(struct snd_usb_substream *subs); 
int snd_usb_audioformat_set_sync_ep(struct snd_usb_audio *chip,

				    struct audioformat *fmt);



const struct audioformat *

snd_usb_find_format(struct list_head *fmt_list_head, snd_pcm_format_t format,

		    unsigned int rate, unsigned int channels, bool strict_match,

		    struct snd_usb_substream *subs);

const struct audioformat *

snd_usb_find_substream_format(struct snd_usb_substream *subs,

			      const struct snd_pcm_hw_params *params);



int snd_usb_hw_params(struct snd_usb_substream *subs,

		      struct snd_pcm_hw_params *hw_params);

int snd_usb_hw_free(struct snd_usb_substream *subs);

#endif /* __USBAUDIO_PCM_H */