Commit 9027c463 authored by Takashi Iwai's avatar Takashi Iwai
Browse files

ALSA: pcm: Call ack() whenever appl_ptr is updated 



Although the ack callback is supposed to be called at each appl_ptr or
hw_ptr update, we missed a few opportunities: namely, forward, rewind
and sync_ptr.

Formerly calling ack at rewind may have leaded to unexpected results
due to the forgotten negative appl_ptr update in indirect-PCM helper,
which is the major user of the PCM ack callback.  But now we fixed
this oversights, thus we can call ack callback safely even at rewind
callback -- of course with the proper handling of the error from the
callback.

This patch adds the calls of ack callback in the places mentioned in
the above.

Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
parent 9ce7b9cf

sound/core/pcm_native.c

+37 −9
Original line number Diff line number Diff line
@@ -2449,13 +2449,35 @@ static int do_pcm_hwsync(struct snd_pcm_substream *substream) 
	}

}



/* increase the appl_ptr; returns the processed frames */

/* update to the given appl_ptr and call ack callback if needed;

 * when an error is returned, take back to the original value

 */

static int apply_appl_ptr(struct snd_pcm_substream *substream,

			  snd_pcm_uframes_t appl_ptr)

{

	struct snd_pcm_runtime *runtime = substream->runtime;

	snd_pcm_uframes_t old_appl_ptr = runtime->control->appl_ptr;

	int ret;



	runtime->control->appl_ptr = appl_ptr;

	if (substream->ops->ack) {

		ret = substream->ops->ack(substream);

		if (ret < 0) {

			runtime->control->appl_ptr = old_appl_ptr;

			return ret;

		}

	}

	return 0;

}



/* increase the appl_ptr; returns the processed frames or a negative error */

static snd_pcm_sframes_t forward_appl_ptr(struct snd_pcm_substream *substream,

					  snd_pcm_uframes_t frames,

					   snd_pcm_sframes_t avail)

{

	struct snd_pcm_runtime *runtime = substream->runtime;

	snd_pcm_sframes_t appl_ptr;

	int ret;



	if (avail <= 0)

		return 0;
@@ -2464,17 +2486,18 @@ static snd_pcm_sframes_t forward_appl_ptr(struct snd_pcm_substream *substream, 
	appl_ptr = runtime->control->appl_ptr + frames;

	if (appl_ptr >= (snd_pcm_sframes_t)runtime->boundary)

		appl_ptr -= runtime->boundary;

	runtime->control->appl_ptr = appl_ptr;

	return frames;

	ret = apply_appl_ptr(substream, appl_ptr);

	return ret < 0 ? ret : frames;

}



/* decrease the appl_ptr; returns the processed frames */

/* decrease the appl_ptr; returns the processed frames or a negative error */

static snd_pcm_sframes_t rewind_appl_ptr(struct snd_pcm_substream *substream,

					 snd_pcm_uframes_t frames,

					 snd_pcm_sframes_t avail)

{

	struct snd_pcm_runtime *runtime = substream->runtime;

	snd_pcm_sframes_t appl_ptr;

	int ret;



	if (avail <= 0)

		return 0;
@@ -2483,8 +2506,8 @@ static snd_pcm_sframes_t rewind_appl_ptr(struct snd_pcm_substream *substream, 
	appl_ptr = runtime->control->appl_ptr - frames;

	if (appl_ptr < 0)

		appl_ptr += runtime->boundary;

	runtime->control->appl_ptr = appl_ptr;

	return frames;

	ret = apply_appl_ptr(substream, appl_ptr);

	return ret < 0 ? ret : frames;

}



static snd_pcm_sframes_t snd_pcm_playback_rewind(struct snd_pcm_substream *substream,
@@ -2610,10 +2633,15 @@ static int snd_pcm_sync_ptr(struct snd_pcm_substream *substream, 
			return err;

	}

	snd_pcm_stream_lock_irq(substream);

	if (!(sync_ptr.flags & SNDRV_PCM_SYNC_PTR_APPL))

		control->appl_ptr = sync_ptr.c.control.appl_ptr;

	else

	if (!(sync_ptr.flags & SNDRV_PCM_SYNC_PTR_APPL)) {

		err = apply_appl_ptr(substream, sync_ptr.c.control.appl_ptr);

		if (err < 0) {

			snd_pcm_stream_unlock_irq(substream);

			return err;

		}

	} else {

		sync_ptr.c.control.appl_ptr = control->appl_ptr;

	}

	if (!(sync_ptr.flags & SNDRV_PCM_SYNC_PTR_AVAIL_MIN))

		control->avail_min = sync_ptr.c.control.avail_min;

	else

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