int line6_pcm_start(struct snd_line6_pcm *line6pcm, int channels)
{
unsigned long flags_old =
__sync_fetch_and_or(&line6pcm->flags, channels);
unsigned long flags_new = flags_old | channels;
int err = 0;
line6pcm->prev_fbuf = NULL;
if (test_flags(flags_old, flags_new, MASK_CAPTURE)) {
/*
Waiting for completion of active URBs in the stop handler is
a bug, we therefore report an error if capturing is restarted
too soon.
*/
if (line6pcm->active_urb_in | line6pcm->unlink_urb_in)
return -EBUSY;
if (!(flags_new & MASK_PCM_ALSA_CAPTURE)) {
err = line6_alloc_capture_buffer(line6pcm);
if (err < 0)
goto pcm_start_error;
}
line6pcm->count_in = 0;
line6pcm->prev_fsize = 0;
err = line6_submit_audio_in_all_urbs(line6pcm);
if (err < 0)
goto pcm_start_error;
}
if (test_flags(flags_old, flags_new, MASK_PLAYBACK)) {
/*
See comment above regarding PCM restart.
*/
if (line6pcm->active_urb_out | line6pcm->unlink_urb_out)
return -EBUSY;
if (!(flags_new & MASK_PCM_ALSA_PLAYBACK)) {
err = line6_alloc_playback_buffer(line6pcm);
if (err < 0)
goto pcm_start_error;
}
line6pcm->count_out = 0;
err = line6_submit_audio_out_all_urbs(line6pcm);
if (err < 0)
goto pcm_start_error;
}
return 0;
pcm_start_error:
__sync_fetch_and_and(&line6pcm->flags, ~channels);
return err;
}
/* start a PCM stream */
static int line6_stream_start(struct snd_line6_pcm *line6pcm, int direction,
int type)
{
unsigned long flags;
struct line6_pcm_stream *pstr = get_stream(line6pcm, direction);
int ret = 0;
spin_lock_irqsave(&pstr->lock, flags);
if (!test_and_set_bit(type, &pstr->running) &&
!(pstr->active_urbs || pstr->unlink_urbs)) {
pstr->count = 0;
/* Submit all currently available URBs */
if (direction == SNDRV_PCM_STREAM_PLAYBACK)
ret = line6_submit_audio_out_all_urbs(line6pcm);
else
ret = line6_submit_audio_in_all_urbs(line6pcm);
}
if (ret < 0)
clear_bit(type, &pstr->running);
spin_unlock_irqrestore(&pstr->lock, flags);
return ret;
}
int line6_pcm_acquire(struct snd_line6_pcm *line6pcm, int channels)
{
unsigned long flags_old, flags_new, flags_final;
int err;
do {
flags_old = ACCESS_ONCE(line6pcm->flags);
flags_new = flags_old | channels;
} while (cmpxchg(&line6pcm->flags, flags_old, flags_new) != flags_old);
flags_final = flags_old;
line6pcm->prev_fbuf = NULL;
if (test_flags(flags_old, flags_new, LINE6_BITS_CAPTURE_BUFFER)) {
/* Invoked multiple times in a row so allocate once only */
if (!line6pcm->buffer_in) {
line6pcm->buffer_in =
kmalloc(LINE6_ISO_BUFFERS * LINE6_ISO_PACKETS *
line6pcm->max_packet_size, GFP_KERNEL);
if (!line6pcm->buffer_in) {
err = -ENOMEM;
goto pcm_acquire_error;
}
flags_final |= channels & LINE6_BITS_CAPTURE_BUFFER;
}
}
if (test_flags(flags_old, flags_new, LINE6_BITS_CAPTURE_STREAM)) {
/*
Waiting for completion of active URBs in the stop handler is
a bug, we therefore report an error if capturing is restarted
too soon.
*/
if (line6pcm->active_urb_in | line6pcm->unlink_urb_in) {
dev_err(line6pcm->line6->ifcdev, "Device not yet ready\n");
return -EBUSY;
}
line6pcm->count_in = 0;
line6pcm->prev_fsize = 0;
err = line6_submit_audio_in_all_urbs(line6pcm);
if (err < 0)
goto pcm_acquire_error;
flags_final |= channels & LINE6_BITS_CAPTURE_STREAM;
}
if (test_flags(flags_old, flags_new, LINE6_BITS_PLAYBACK_BUFFER)) {
/* Invoked multiple times in a row so allocate once only */
if (!line6pcm->buffer_out) {
line6pcm->buffer_out =
kmalloc(LINE6_ISO_BUFFERS * LINE6_ISO_PACKETS *
line6pcm->max_packet_size, GFP_KERNEL);
if (!line6pcm->buffer_out) {
err = -ENOMEM;
goto pcm_acquire_error;
}
flags_final |= channels & LINE6_BITS_PLAYBACK_BUFFER;
}
}
if (test_flags(flags_old, flags_new, LINE6_BITS_PLAYBACK_STREAM)) {
/*
See comment above regarding PCM restart.
*/
if (line6pcm->active_urb_out | line6pcm->unlink_urb_out) {
dev_err(line6pcm->line6->ifcdev, "Device not yet ready\n");
return -EBUSY;
}
line6pcm->count_out = 0;
err = line6_submit_audio_out_all_urbs(line6pcm);
if (err < 0)
goto pcm_acquire_error;
flags_final |= channels & LINE6_BITS_PLAYBACK_STREAM;
}
return 0;
pcm_acquire_error:
/*
If not all requested resources/streams could be obtained, release
those which were successfully obtained (if any).
*/
line6_pcm_release(line6pcm, flags_final & channels);
return err;
}
int line6_pcm_start(struct snd_line6_pcm *line6pcm, int channels)
{
unsigned long flags_old =
__sync_fetch_and_or(&line6pcm->flags, channels);
unsigned long flags_new = flags_old | channels;
int err = 0;
#if LINE6_BACKUP_MONITOR_SIGNAL
if (!(line6pcm->line6->properties->capabilities & LINE6_BIT_HWMON)) {
line6pcm->prev_fbuf =
kmalloc(LINE6_ISO_PACKETS * line6pcm->max_packet_size,
GFP_KERNEL);
if (!line6pcm->prev_fbuf) {
dev_err(line6pcm->line6->ifcdev,
"cannot malloc monitor buffer\n");
return -ENOMEM;
}
}
#else
line6pcm->prev_fbuf = NULL;
#endif
if (((flags_old & MASK_CAPTURE) == 0) &&
((flags_new & MASK_CAPTURE) != 0)) {
/*
Waiting for completion of active URBs in the stop handler is
a bug, we therefore report an error if capturing is restarted
too soon.
*/
if (line6pcm->active_urb_in | line6pcm->unlink_urb_in)
return -EBUSY;
line6pcm->buffer_in =
kmalloc(LINE6_ISO_BUFFERS * LINE6_ISO_PACKETS *
line6pcm->max_packet_size, GFP_KERNEL);
if (!line6pcm->buffer_in) {
dev_err(line6pcm->line6->ifcdev,
"cannot malloc capture buffer\n");
return -ENOMEM;
}
line6pcm->count_in = 0;
line6pcm->prev_fsize = 0;
err = line6_submit_audio_in_all_urbs(line6pcm);
if (err < 0) {
__sync_fetch_and_and(&line6pcm->flags, ~channels);
return err;
}
}
if (((flags_old & MASK_PLAYBACK) == 0) &&
((flags_new & MASK_PLAYBACK) != 0)) {
/*
See comment above regarding PCM restart.
*/
if (line6pcm->active_urb_out | line6pcm->unlink_urb_out)
return -EBUSY;
line6pcm->buffer_out =
kmalloc(LINE6_ISO_BUFFERS * LINE6_ISO_PACKETS *
line6pcm->max_packet_size, GFP_KERNEL);
if (!line6pcm->buffer_out) {
dev_err(line6pcm->line6->ifcdev,
"cannot malloc playback buffer\n");
return -ENOMEM;
}
line6pcm->count_out = 0;
err = line6_submit_audio_out_all_urbs(line6pcm);
if (err < 0) {
__sync_fetch_and_and(&line6pcm->flags, ~channels);
return err;
}
}
return 0;
}
