[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 <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
This commit is contained in:
Takashi Iwai 2008-01-08 18:08:14 +01:00 committed by Jaroslav Kysela
parent d948035a92
commit 130755108b

View file

@ -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;
err = wait_for_avail_min(substream, &avail);
if (err < 0)
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;
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;
err = wait_for_avail_min(substream, &avail);
if (err < 0)
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;
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;