From 130755108ba03461f69da990e54e02a254accd23 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Tue, 8 Jan 2008 18:08:14 +0100 Subject: [PATCH] [ALSA] PCM - clean up snd_pcm_lib_read/write Introduce a common helper function for snd_pcm_lib_read and snd_pcm_lib_write for cleaning up the code. Signed-off-by: Takashi Iwai Signed-off-by: Jaroslav Kysela --- sound/core/pcm_lib.c | 216 ++++++++++++++++++--------------------------------- 1 file changed, 76 insertions(+), 140 deletions(-) diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c index c1c1556..b406630 100644 --- a/sound/core/pcm_lib.c +++ b/sound/core/pcm_lib.c @@ -1591,6 +1591,71 @@ void snd_pcm_period_elapsed(struct snd_pcm_substream *substream) EXPORT_SYMBOL(snd_pcm_period_elapsed); +/* + * Wait until avail_min data becomes available + * Returns a negative error code if any error occurs during operation. + * The available space is stored on availp. When err = 0 and avail = 0 + * on the capture stream, it indicates the stream is in DRAINING state. + */ +static int wait_for_avail_min(struct snd_pcm_substream *substream, + snd_pcm_uframes_t *availp) +{ + struct snd_pcm_runtime *runtime = substream->runtime; + int is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK; + wait_queue_t wait; + int err = 0; + snd_pcm_uframes_t avail = 0; + long tout; + + init_waitqueue_entry(&wait, current); + add_wait_queue(&runtime->sleep, &wait); + for (;;) { + if (signal_pending(current)) { + err = -ERESTARTSYS; + break; + } + set_current_state(TASK_INTERRUPTIBLE); + snd_pcm_stream_unlock_irq(substream); + tout = schedule_timeout(msecs_to_jiffies(10000)); + snd_pcm_stream_lock_irq(substream); + switch (runtime->status->state) { + case SNDRV_PCM_STATE_SUSPENDED: + err = -ESTRPIPE; + goto _endloop; + case SNDRV_PCM_STATE_XRUN: + err = -EPIPE; + goto _endloop; + case SNDRV_PCM_STATE_DRAINING: + if (is_playback) + err = -EPIPE; + else + avail = 0; /* indicate draining */ + goto _endloop; + case SNDRV_PCM_STATE_OPEN: + case SNDRV_PCM_STATE_SETUP: + case SNDRV_PCM_STATE_DISCONNECTED: + err = -EBADFD; + goto _endloop; + } + if (!tout) { + snd_printd("%s write error (DMA or IRQ trouble?)\n", + is_playback ? "playback" : "capture"); + err = -EIO; + break; + } + if (is_playback) + avail = snd_pcm_playback_avail(runtime); + else + avail = snd_pcm_capture_avail(runtime); + if (avail >= runtime->control->avail_min) + break; + } + _endloop: + remove_wait_queue(&runtime->sleep, &wait); + *availp = avail; + return err; +} + static int snd_pcm_lib_write_transfer(struct snd_pcm_substream *substream, unsigned int hwoff, unsigned long data, unsigned int off, @@ -1653,79 +1718,14 @@ static snd_pcm_sframes_t snd_pcm_lib_write1(struct snd_pcm_substream *substream, if (runtime->sleep_min == 0 && runtime->status->state == SNDRV_PCM_STATE_RUNNING) snd_pcm_update_hw_ptr(substream); avail = snd_pcm_playback_avail(runtime); - if (!avail || - (snd_pcm_running(substream) && - (avail < runtime->control->avail_min && size > avail))) { - wait_queue_t wait; - enum { READY, SIGNALED, ERROR, SUSPENDED, EXPIRED, DROPPED } state; - long tout; - + if (!avail) { if (nonblock) { err = -EAGAIN; goto _end_unlock; } - - init_waitqueue_entry(&wait, current); - add_wait_queue(&runtime->sleep, &wait); - while (1) { - if (signal_pending(current)) { - state = SIGNALED; - break; - } - set_current_state(TASK_INTERRUPTIBLE); - snd_pcm_stream_unlock_irq(substream); - tout = schedule_timeout(10 * HZ); - snd_pcm_stream_lock_irq(substream); - if (tout == 0) { - if (runtime->status->state != SNDRV_PCM_STATE_PREPARED && - runtime->status->state != SNDRV_PCM_STATE_PAUSED) { - state = runtime->status->state == SNDRV_PCM_STATE_SUSPENDED ? SUSPENDED : EXPIRED; - break; - } - } - switch (runtime->status->state) { - case SNDRV_PCM_STATE_XRUN: - case SNDRV_PCM_STATE_DRAINING: - state = ERROR; - goto _end_loop; - case SNDRV_PCM_STATE_SUSPENDED: - state = SUSPENDED; - goto _end_loop; - case SNDRV_PCM_STATE_SETUP: - state = DROPPED; - goto _end_loop; - default: - break; - } - avail = snd_pcm_playback_avail(runtime); - if (avail >= runtime->control->avail_min) { - state = READY; - break; - } - } - _end_loop: - remove_wait_queue(&runtime->sleep, &wait); - - switch (state) { - case ERROR: - err = -EPIPE; - goto _end_unlock; - case SUSPENDED: - err = -ESTRPIPE; - goto _end_unlock; - case SIGNALED: - err = -ERESTARTSYS; - goto _end_unlock; - case EXPIRED: - snd_printd("playback write error (DMA or IRQ trouble?)\n"); - err = -EIO; - goto _end_unlock; - case DROPPED: - err = -EBADFD; + err = wait_for_avail_min(substream, &avail); + if (err < 0) goto _end_unlock; - default: - break; - } } frames = size > avail ? avail : size; cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size; @@ -1925,86 +1925,22 @@ static snd_pcm_sframes_t snd_pcm_lib_read1(struct snd_pcm_substream *substream, snd_pcm_uframes_t cont; if (runtime->sleep_min == 0 && runtime->status->state == SNDRV_PCM_STATE_RUNNING) snd_pcm_update_hw_ptr(substream); - __draining: avail = snd_pcm_capture_avail(runtime); - if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) { - if (!avail) { - err = -EPIPE; + if (!avail) { + if (runtime->status->state == + SNDRV_PCM_STATE_DRAINING) { + snd_pcm_stop(substream, SNDRV_PCM_STATE_SETUP); goto _end_unlock; } - } else if (avail < runtime->control->avail_min && - size > avail) { - wait_queue_t wait; - enum { READY, SIGNALED, ERROR, SUSPENDED, EXPIRED, DROPPED } state; - long tout; - if (nonblock) { err = -EAGAIN; goto _end_unlock; } - - init_waitqueue_entry(&wait, current); - add_wait_queue(&runtime->sleep, &wait); - while (1) { - if (signal_pending(current)) { - state = SIGNALED; - break; - } - set_current_state(TASK_INTERRUPTIBLE); - snd_pcm_stream_unlock_irq(substream); - tout = schedule_timeout(10 * HZ); - snd_pcm_stream_lock_irq(substream); - if (tout == 0) { - if (runtime->status->state != SNDRV_PCM_STATE_PREPARED && - runtime->status->state != SNDRV_PCM_STATE_PAUSED) { - state = runtime->status->state == SNDRV_PCM_STATE_SUSPENDED ? SUSPENDED : EXPIRED; - break; - } - } - switch (runtime->status->state) { - case SNDRV_PCM_STATE_XRUN: - state = ERROR; - goto _end_loop; - case SNDRV_PCM_STATE_SUSPENDED: - state = SUSPENDED; - goto _end_loop; - case SNDRV_PCM_STATE_DRAINING: - goto __draining; - case SNDRV_PCM_STATE_SETUP: - state = DROPPED; - goto _end_loop; - default: - break; - } - avail = snd_pcm_capture_avail(runtime); - if (avail >= runtime->control->avail_min) { - state = READY; - break; - } - } - _end_loop: - remove_wait_queue(&runtime->sleep, &wait); - - switch (state) { - case ERROR: - err = -EPIPE; - goto _end_unlock; - case SUSPENDED: - err = -ESTRPIPE; - goto _end_unlock; - case SIGNALED: - err = -ERESTARTSYS; - goto _end_unlock; - case EXPIRED: - snd_printd("capture read error (DMA or IRQ trouble?)\n"); - err = -EIO; - goto _end_unlock; - case DROPPED: - err = -EBADFD; + err = wait_for_avail_min(substream, &avail); + if (err < 0) goto _end_unlock; - default: - break; - } + if (!avail) + continue; /* draining */ } frames = size > avail ? avail : size; cont = runtime->buffer_size - runtime->control->appl_ptr % runtime->buffer_size; -- 2.7.4