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: Takashi Iwai tiwai@suse.de --- sound/core/pcm_native.c | 46 +++++++++++++++++++++++++++++++++++++--------- 1 file changed, 37 insertions(+), 9 deletions(-)
diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c index ecde57afa45a..7bc4a0bbad6f 100644 --- a/sound/core/pcm_native.c +++ b/sound/core/pcm_native.c @@ -2455,13 +2455,35 @@ 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; @@ -2470,17 +2492,18 @@ 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; @@ -2489,8 +2512,8 @@ 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, @@ -2620,10 +2643,15 @@ 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