diff options
Diffstat (limited to 'sound/drivers/aloop.c')
| -rw-r--r-- | sound/drivers/aloop.c | 1837 |
1 files changed, 1837 insertions, 0 deletions
diff --git a/sound/drivers/aloop.c b/sound/drivers/aloop.c new file mode 100644 index 000000000..a38e602b4 --- /dev/null +++ b/sound/drivers/aloop.c @@ -0,0 +1,1837 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Loopback soundcard + * + * Original code: + * Copyright (c) by Jaroslav Kysela <perex@perex.cz> + * + * More accurate positioning and full-duplex support: + * Copyright (c) Ahmet İnan <ainan at mathematik.uni-freiburg.de> + * + * Major (almost complete) rewrite: + * Copyright (c) by Takashi Iwai <tiwai@suse.de> + * + * A next major update in 2010 (separate timers for playback and capture): + * Copyright (c) Jaroslav Kysela <perex@perex.cz> + */ + +#include <linux/init.h> +#include <linux/jiffies.h> +#include <linux/slab.h> +#include <linux/time.h> +#include <linux/wait.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <sound/core.h> +#include <sound/control.h> +#include <sound/pcm.h> +#include <sound/pcm_params.h> +#include <sound/info.h> +#include <sound/initval.h> +#include <sound/timer.h> + +MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>"); +MODULE_DESCRIPTION("A loopback soundcard"); +MODULE_LICENSE("GPL"); + +#define MAX_PCM_SUBSTREAMS 8 + +static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX; /* Index 0-MAX */ +static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR; /* ID for this card */ +static bool enable[SNDRV_CARDS] = {1, [1 ... (SNDRV_CARDS - 1)] = 0}; +static int pcm_substreams[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 8}; +static int pcm_notify[SNDRV_CARDS]; +static char *timer_source[SNDRV_CARDS]; + +module_param_array(index, int, NULL, 0444); +MODULE_PARM_DESC(index, "Index value for loopback soundcard."); +module_param_array(id, charp, NULL, 0444); +MODULE_PARM_DESC(id, "ID string for loopback soundcard."); +module_param_array(enable, bool, NULL, 0444); +MODULE_PARM_DESC(enable, "Enable this loopback soundcard."); +module_param_array(pcm_substreams, int, NULL, 0444); +MODULE_PARM_DESC(pcm_substreams, "PCM substreams # (1-8) for loopback driver."); +module_param_array(pcm_notify, int, NULL, 0444); +MODULE_PARM_DESC(pcm_notify, "Break capture when PCM format/rate/channels changes."); +module_param_array(timer_source, charp, NULL, 0444); +MODULE_PARM_DESC(timer_source, "Sound card name or number and device/subdevice number of timer to be used. Empty string for jiffies timer [default]."); + +#define NO_PITCH 100000 + +#define CABLE_VALID_PLAYBACK BIT(SNDRV_PCM_STREAM_PLAYBACK) +#define CABLE_VALID_CAPTURE BIT(SNDRV_PCM_STREAM_CAPTURE) +#define CABLE_VALID_BOTH (CABLE_VALID_PLAYBACK | CABLE_VALID_CAPTURE) + +struct loopback_cable; +struct loopback_pcm; + +struct loopback_ops { + /* optional + * call in loopback->cable_lock + */ + int (*open)(struct loopback_pcm *dpcm); + /* required + * call in cable->lock + */ + int (*start)(struct loopback_pcm *dpcm); + /* required + * call in cable->lock + */ + int (*stop)(struct loopback_pcm *dpcm); + /* optional */ + int (*stop_sync)(struct loopback_pcm *dpcm); + /* optional */ + int (*close_substream)(struct loopback_pcm *dpcm); + /* optional + * call in loopback->cable_lock + */ + int (*close_cable)(struct loopback_pcm *dpcm); + /* optional + * call in cable->lock + */ + unsigned int (*pos_update)(struct loopback_cable *cable); + /* optional */ + void (*dpcm_info)(struct loopback_pcm *dpcm, + struct snd_info_buffer *buffer); +}; + +struct loopback_cable { + spinlock_t lock; + struct loopback_pcm *streams[2]; + struct snd_pcm_hardware hw; + /* flags */ + unsigned int valid; + unsigned int running; + unsigned int pause; + /* timer specific */ + const struct loopback_ops *ops; + /* If sound timer is used */ + struct { + int stream; + struct snd_timer_id id; + struct work_struct event_work; + struct snd_timer_instance *instance; + } snd_timer; +}; + +struct loopback_setup { + unsigned int notify: 1; + unsigned int rate_shift; + snd_pcm_format_t format; + unsigned int rate; + unsigned int channels; + struct snd_ctl_elem_id active_id; + struct snd_ctl_elem_id format_id; + struct snd_ctl_elem_id rate_id; + struct snd_ctl_elem_id channels_id; +}; + +struct loopback { + struct snd_card *card; + struct mutex cable_lock; + struct loopback_cable *cables[MAX_PCM_SUBSTREAMS][2]; + struct snd_pcm *pcm[2]; + struct loopback_setup setup[MAX_PCM_SUBSTREAMS][2]; + const char *timer_source; +}; + +struct loopback_pcm { + struct loopback *loopback; + struct snd_pcm_substream *substream; + struct loopback_cable *cable; + unsigned int pcm_buffer_size; + unsigned int buf_pos; /* position in buffer */ + unsigned int silent_size; + /* PCM parameters */ + unsigned int pcm_period_size; + unsigned int pcm_bps; /* bytes per second */ + unsigned int pcm_salign; /* bytes per sample * channels */ + unsigned int pcm_rate_shift; /* rate shift value */ + /* flags */ + unsigned int period_update_pending :1; + /* timer stuff */ + unsigned int irq_pos; /* fractional IRQ position in jiffies + * ticks + */ + unsigned int period_size_frac; /* period size in jiffies ticks */ + unsigned int last_drift; + unsigned long last_jiffies; + /* If jiffies timer is used */ + struct timer_list timer; +}; + +static struct platform_device *devices[SNDRV_CARDS]; + +static inline unsigned int byte_pos(struct loopback_pcm *dpcm, unsigned int x) +{ + if (dpcm->pcm_rate_shift == NO_PITCH) { + x /= HZ; + } else { + x = div_u64(NO_PITCH * (unsigned long long)x, + HZ * (unsigned long long)dpcm->pcm_rate_shift); + } + return x - (x % dpcm->pcm_salign); +} + +static inline unsigned int frac_pos(struct loopback_pcm *dpcm, unsigned int x) +{ + if (dpcm->pcm_rate_shift == NO_PITCH) { /* no pitch */ + return x * HZ; + } else { + x = div_u64(dpcm->pcm_rate_shift * (unsigned long long)x * HZ, + NO_PITCH); + } + return x; +} + +static inline struct loopback_setup *get_setup(struct loopback_pcm *dpcm) +{ + int device = dpcm->substream->pstr->pcm->device; + + if (dpcm->substream->stream == SNDRV_PCM_STREAM_PLAYBACK) + device ^= 1; + return &dpcm->loopback->setup[dpcm->substream->number][device]; +} + +static inline unsigned int get_notify(struct loopback_pcm *dpcm) +{ + return get_setup(dpcm)->notify; +} + +static inline unsigned int get_rate_shift(struct loopback_pcm *dpcm) +{ + return get_setup(dpcm)->rate_shift; +} + +/* call in cable->lock */ +static int loopback_jiffies_timer_start(struct loopback_pcm *dpcm) +{ + unsigned long tick; + unsigned int rate_shift = get_rate_shift(dpcm); + + if (rate_shift != dpcm->pcm_rate_shift) { + dpcm->pcm_rate_shift = rate_shift; + dpcm->period_size_frac = frac_pos(dpcm, dpcm->pcm_period_size); + } + if (dpcm->period_size_frac <= dpcm->irq_pos) { + dpcm->irq_pos %= dpcm->period_size_frac; + dpcm->period_update_pending = 1; + } + tick = dpcm->period_size_frac - dpcm->irq_pos; + tick = DIV_ROUND_UP(tick, dpcm->pcm_bps); + mod_timer(&dpcm->timer, jiffies + tick); + + return 0; +} + +/* call in cable->lock */ +static int loopback_snd_timer_start(struct loopback_pcm *dpcm) +{ + struct loopback_cable *cable = dpcm->cable; + int err; + + /* Loopback device has to use same period as timer card. Therefore + * wake up for each snd_pcm_period_elapsed() call of timer card. + */ + err = snd_timer_start(cable->snd_timer.instance, 1); + if (err < 0) { + /* do not report error if trying to start but already + * running. For example called by opposite substream + * of the same cable + */ + if (err == -EBUSY) + return 0; + + pcm_err(dpcm->substream->pcm, + "snd_timer_start(%d,%d,%d) failed with %d", + cable->snd_timer.id.card, + cable->snd_timer.id.device, + cable->snd_timer.id.subdevice, + err); + } + + return err; +} + +/* call in cable->lock */ +static inline int loopback_jiffies_timer_stop(struct loopback_pcm *dpcm) +{ + del_timer(&dpcm->timer); + dpcm->timer.expires = 0; + + return 0; +} + +/* call in cable->lock */ +static int loopback_snd_timer_stop(struct loopback_pcm *dpcm) +{ + struct loopback_cable *cable = dpcm->cable; + int err; + + /* only stop if both devices (playback and capture) are not running */ + if (cable->running ^ cable->pause) + return 0; + + err = snd_timer_stop(cable->snd_timer.instance); + if (err < 0) { + pcm_err(dpcm->substream->pcm, + "snd_timer_stop(%d,%d,%d) failed with %d", + cable->snd_timer.id.card, + cable->snd_timer.id.device, + cable->snd_timer.id.subdevice, + err); + } + + return err; +} + +static inline int loopback_jiffies_timer_stop_sync(struct loopback_pcm *dpcm) +{ + del_timer_sync(&dpcm->timer); + + return 0; +} + +/* call in loopback->cable_lock */ +static int loopback_snd_timer_close_cable(struct loopback_pcm *dpcm) +{ + struct loopback_cable *cable = dpcm->cable; + + /* snd_timer was not opened */ + if (!cable->snd_timer.instance) + return 0; + + /* will only be called from free_cable() when other stream was + * already closed. Other stream cannot be reopened as long as + * loopback->cable_lock is locked. Therefore no need to lock + * cable->lock; + */ + snd_timer_close(cable->snd_timer.instance); + + /* wait till drain work has finished if requested */ + cancel_work_sync(&cable->snd_timer.event_work); + + snd_timer_instance_free(cable->snd_timer.instance); + memset(&cable->snd_timer, 0, sizeof(cable->snd_timer)); + + return 0; +} + +static int loopback_check_format(struct loopback_cable *cable, int stream) +{ + struct snd_pcm_runtime *runtime, *cruntime; + struct loopback_setup *setup; + struct snd_card *card; + int check; + + if (cable->valid != CABLE_VALID_BOTH) { + if (stream == SNDRV_PCM_STREAM_PLAYBACK) + goto __notify; + return 0; + } + runtime = cable->streams[SNDRV_PCM_STREAM_PLAYBACK]-> + substream->runtime; + cruntime = cable->streams[SNDRV_PCM_STREAM_CAPTURE]-> + substream->runtime; + check = runtime->format != cruntime->format || + runtime->rate != cruntime->rate || + runtime->channels != cruntime->channels; + if (!check) + return 0; + if (stream == SNDRV_PCM_STREAM_CAPTURE) { + return -EIO; + } else { + snd_pcm_stop(cable->streams[SNDRV_PCM_STREAM_CAPTURE]-> + substream, SNDRV_PCM_STATE_DRAINING); + __notify: + runtime = cable->streams[SNDRV_PCM_STREAM_PLAYBACK]-> + substream->runtime; + setup = get_setup(cable->streams[SNDRV_PCM_STREAM_PLAYBACK]); + card = cable->streams[SNDRV_PCM_STREAM_PLAYBACK]->loopback->card; + if (setup->format != runtime->format) { + snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE, + &setup->format_id); + setup->format = runtime->format; + } + if (setup->rate != runtime->rate) { + snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE, + &setup->rate_id); + setup->rate = runtime->rate; + } + if (setup->channels != runtime->channels) { + snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE, + &setup->channels_id); + setup->channels = runtime->channels; + } + } + return 0; +} + +static void loopback_active_notify(struct loopback_pcm *dpcm) +{ + snd_ctl_notify(dpcm->loopback->card, + SNDRV_CTL_EVENT_MASK_VALUE, + &get_setup(dpcm)->active_id); +} + +static int loopback_trigger(struct snd_pcm_substream *substream, int cmd) +{ + struct snd_pcm_runtime *runtime = substream->runtime; + struct loopback_pcm *dpcm = runtime->private_data; + struct loopback_cable *cable = dpcm->cable; + int err = 0, stream = 1 << substream->stream; + + switch (cmd) { + case SNDRV_PCM_TRIGGER_START: + err = loopback_check_format(cable, substream->stream); + if (err < 0) + return err; + dpcm->last_jiffies = jiffies; + dpcm->pcm_rate_shift = 0; + dpcm->last_drift = 0; + spin_lock(&cable->lock); + cable->running |= stream; + cable->pause &= ~stream; + err = cable->ops->start(dpcm); + spin_unlock(&cable->lock); + if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) + loopback_active_notify(dpcm); + break; + case SNDRV_PCM_TRIGGER_STOP: + spin_lock(&cable->lock); + cable->running &= ~stream; + cable->pause &= ~stream; + err = cable->ops->stop(dpcm); + spin_unlock(&cable->lock); + if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) + loopback_active_notify(dpcm); + break; + case SNDRV_PCM_TRIGGER_PAUSE_PUSH: + case SNDRV_PCM_TRIGGER_SUSPEND: + spin_lock(&cable->lock); + cable->pause |= stream; + err = cable->ops->stop(dpcm); + spin_unlock(&cable->lock); + if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) + loopback_active_notify(dpcm); + break; + case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: + case SNDRV_PCM_TRIGGER_RESUME: + spin_lock(&cable->lock); + dpcm->last_jiffies = jiffies; + cable->pause &= ~stream; + err = cable->ops->start(dpcm); + spin_unlock(&cable->lock); + if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) + loopback_active_notify(dpcm); + break; + default: + return -EINVAL; + } + return err; +} + +static void params_change(struct snd_pcm_substream *substream) +{ + struct snd_pcm_runtime *runtime = substream->runtime; + struct loopback_pcm *dpcm = runtime->private_data; + struct loopback_cable *cable = dpcm->cable; + + cable->hw.formats = pcm_format_to_bits(runtime->format); + cable->hw.rate_min = runtime->rate; + cable->hw.rate_max = runtime->rate; + cable->hw.channels_min = runtime->channels; + cable->hw.channels_max = runtime->channels; + + if (cable->snd_timer.instance) { + cable->hw.period_bytes_min = + frames_to_bytes(runtime, runtime->period_size); + cable->hw.period_bytes_max = cable->hw.period_bytes_min; + } + +} + +static int loopback_prepare(struct snd_pcm_substream *substream) +{ + struct snd_pcm_runtime *runtime = substream->runtime; + struct loopback_pcm *dpcm = runtime->private_data; + struct loopback_cable *cable = dpcm->cable; + int err, bps, salign; + + if (cable->ops->stop_sync) { + err = cable->ops->stop_sync(dpcm); + if (err < 0) + return err; + } + + salign = (snd_pcm_format_physical_width(runtime->format) * + runtime->channels) / 8; + bps = salign * runtime->rate; + if (bps <= 0 || salign <= 0) + return -EINVAL; + + dpcm->buf_pos = 0; + dpcm->pcm_buffer_size = frames_to_bytes(runtime, runtime->buffer_size); + if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) { + /* clear capture buffer */ + dpcm->silent_size = dpcm->pcm_buffer_size; + snd_pcm_format_set_silence(runtime->format, runtime->dma_area, + runtime->buffer_size * runtime->channels); + } + + dpcm->irq_pos = 0; + dpcm->period_update_pending = 0; + dpcm->pcm_bps = bps; + dpcm->pcm_salign = salign; + dpcm->pcm_period_size = frames_to_bytes(runtime, runtime->period_size); + + mutex_lock(&dpcm->loopback->cable_lock); + if (!(cable->valid & ~(1 << substream->stream)) || + (get_setup(dpcm)->notify && + substream->stream == SNDRV_PCM_STREAM_PLAYBACK)) + params_change(substream); + cable->valid |= 1 << substream->stream; + mutex_unlock(&dpcm->loopback->cable_lock); + + return 0; +} + +static void clear_capture_buf(struct loopback_pcm *dpcm, unsigned int bytes) +{ + struct snd_pcm_runtime *runtime = dpcm->substream->runtime; + char *dst = runtime->dma_area; + unsigned int dst_off = dpcm->buf_pos; + + if (dpcm->silent_size >= dpcm->pcm_buffer_size) + return; + if (dpcm->silent_size + bytes > dpcm->pcm_buffer_size) + bytes = dpcm->pcm_buffer_size - dpcm->silent_size; + + for (;;) { + unsigned int size = bytes; + if (dst_off + size > dpcm->pcm_buffer_size) + size = dpcm->pcm_buffer_size - dst_off; + snd_pcm_format_set_silence(runtime->format, dst + dst_off, + bytes_to_frames(runtime, size) * + runtime->channels); + dpcm->silent_size += size; + bytes -= size; + if (!bytes) + break; + dst_off = 0; + } +} + +static void copy_play_buf(struct loopback_pcm *play, + struct loopback_pcm *capt, + unsigned int bytes) +{ + struct snd_pcm_runtime *runtime = play->substream->runtime; + char *src = runtime->dma_area; + char *dst = capt->substream->runtime->dma_area; + unsigned int src_off = play->buf_pos; + unsigned int dst_off = capt->buf_pos; + unsigned int clear_bytes = 0; + + /* check if playback is draining, trim the capture copy size + * when our pointer is at the end of playback ring buffer */ + if (runtime->state == SNDRV_PCM_STATE_DRAINING && + snd_pcm_playback_hw_avail(runtime) < runtime->buffer_size) { + snd_pcm_uframes_t appl_ptr, appl_ptr1, diff; + appl_ptr = appl_ptr1 = runtime->control->appl_ptr; + appl_ptr1 -= appl_ptr1 % runtime->buffer_size; + appl_ptr1 += play->buf_pos / play->pcm_salign; + if (appl_ptr < appl_ptr1) + appl_ptr1 -= runtime->buffer_size; + diff = (appl_ptr - appl_ptr1) * play->pcm_salign; + if (diff < bytes) { + clear_bytes = bytes - diff; + bytes = diff; + } + } + + for (;;) { + unsigned int size = bytes; + if (src_off + size > play->pcm_buffer_size) + size = play->pcm_buffer_size - src_off; + if (dst_off + size > capt->pcm_buffer_size) + size = capt->pcm_buffer_size - dst_off; + memcpy(dst + dst_off, src + src_off, size); + capt->silent_size = 0; + bytes -= size; + if (!bytes) + break; + src_off = (src_off + size) % play->pcm_buffer_size; + dst_off = (dst_off + size) % capt->pcm_buffer_size; + } + + if (clear_bytes > 0) { + clear_capture_buf(capt, clear_bytes); + capt->silent_size = 0; + } +} + +static inline unsigned int bytepos_delta(struct loopback_pcm *dpcm, + unsigned int jiffies_delta) +{ + unsigned long last_pos; + unsigned int delta; + + last_pos = byte_pos(dpcm, dpcm->irq_pos); + dpcm->irq_pos += jiffies_delta * dpcm->pcm_bps; + delta = byte_pos(dpcm, dpcm->irq_pos) - last_pos; + if (delta >= dpcm->last_drift) + delta -= dpcm->last_drift; + dpcm->last_drift = 0; + if (dpcm->irq_pos >= dpcm->period_size_frac) { + dpcm->irq_pos %= dpcm->period_size_frac; + dpcm->period_update_pending = 1; + } + return delta; +} + +static inline void bytepos_finish(struct loopback_pcm *dpcm, + unsigned int delta) +{ + dpcm->buf_pos += delta; + dpcm->buf_pos %= dpcm->pcm_buffer_size; +} + +/* call in cable->lock */ +static unsigned int loopback_jiffies_timer_pos_update + (struct loopback_cable *cable) +{ + struct loopback_pcm *dpcm_play = + cable->streams[SNDRV_PCM_STREAM_PLAYBACK]; + struct loopback_pcm *dpcm_capt = + cable->streams[SNDRV_PCM_STREAM_CAPTURE]; + unsigned long delta_play = 0, delta_capt = 0, cur_jiffies; + unsigned int running, count1, count2; + + cur_jiffies = jiffies; + running = cable->running ^ cable->pause; + if (running & (1 << SNDRV_PCM_STREAM_PLAYBACK)) { + delta_play = cur_jiffies - dpcm_play->last_jiffies; + dpcm_play->last_jiffies += delta_play; + } + + if (running & (1 << SNDRV_PCM_STREAM_CAPTURE)) { + delta_capt = cur_jiffies - dpcm_capt->last_jiffies; + dpcm_capt->last_jiffies += delta_capt; + } + + if (delta_play == 0 && delta_capt == 0) + goto unlock; + + if (delta_play > delta_capt) { + count1 = bytepos_delta(dpcm_play, delta_play - delta_capt); + bytepos_finish(dpcm_play, count1); + delta_play = delta_capt; + } else if (delta_play < delta_capt) { + count1 = bytepos_delta(dpcm_capt, delta_capt - delta_play); + clear_capture_buf(dpcm_capt, count1); + bytepos_finish(dpcm_capt, count1); + delta_capt = delta_play; + } + + if (delta_play == 0 && delta_capt == 0) + goto unlock; + + /* note delta_capt == delta_play at this moment */ + count1 = bytepos_delta(dpcm_play, delta_play); + count2 = bytepos_delta(dpcm_capt, delta_capt); + if (count1 < count2) { + dpcm_capt->last_drift = count2 - count1; + count1 = count2; + } else if (count1 > count2) { + dpcm_play->last_drift = count1 - count2; + } + copy_play_buf(dpcm_play, dpcm_capt, count1); + bytepos_finish(dpcm_play, count1); + bytepos_finish(dpcm_capt, count1); + unlock: + return running; +} + +static void loopback_jiffies_timer_function(struct timer_list *t) +{ + struct loopback_pcm *dpcm = from_timer(dpcm, t, timer); + unsigned long flags; + + spin_lock_irqsave(&dpcm->cable->lock, flags); + if (loopback_jiffies_timer_pos_update(dpcm->cable) & + (1 << dpcm->substream->stream)) { + loopback_jiffies_timer_start(dpcm); + if (dpcm->period_update_pending) { + dpcm->period_update_pending = 0; + spin_unlock_irqrestore(&dpcm->cable->lock, flags); + /* need to unlock before calling below */ + snd_pcm_period_elapsed(dpcm->substream); + return; + } + } + spin_unlock_irqrestore(&dpcm->cable->lock, flags); +} + +/* call in cable->lock */ +static int loopback_snd_timer_check_resolution(struct snd_pcm_runtime *runtime, + unsigned long resolution) +{ + if (resolution != runtime->timer_resolution) { + struct loopback_pcm *dpcm = runtime->private_data; + struct loopback_cable *cable = dpcm->cable; + /* Worst case estimation of possible values for resolution + * resolution <= (512 * 1024) frames / 8kHz in nsec + * resolution <= 65.536.000.000 nsec + * + * period_size <= 65.536.000.000 nsec / 1000nsec/usec * 192kHz + + * 500.000 + * period_size <= 12.582.912.000.000 <64bit + * / 1.000.000 usec/sec + */ + snd_pcm_uframes_t period_size_usec = + resolution / 1000 * runtime->rate; + /* round to nearest sample rate */ + snd_pcm_uframes_t period_size = + (period_size_usec + 500 * 1000) / (1000 * 1000); + + pcm_err(dpcm->substream->pcm, + "Period size (%lu frames) of loopback device is not corresponding to timer resolution (%lu nsec = %lu frames) of card timer %d,%d,%d. Use period size of %lu frames for loopback device.", + runtime->period_size, resolution, period_size, + cable->snd_timer.id.card, + cable->snd_timer.id.device, + cable->snd_timer.id.subdevice, + period_size); + return -EINVAL; + } + return 0; +} + +static void loopback_snd_timer_period_elapsed(struct loopback_cable *cable, + int event, + unsigned long resolution) +{ + struct loopback_pcm *dpcm_play, *dpcm_capt; + struct snd_pcm_substream *substream_play, *substream_capt; + struct snd_pcm_runtime *valid_runtime; + unsigned int running, elapsed_bytes; + unsigned long flags; + + spin_lock_irqsave(&cable->lock, flags); + running = cable->running ^ cable->pause; + /* no need to do anything if no stream is running */ + if (!running) { + spin_unlock_irqrestore(&cable->lock, flags); + return; + } + + dpcm_play = cable->streams[SNDRV_PCM_STREAM_PLAYBACK]; + dpcm_capt = cable->streams[SNDRV_PCM_STREAM_CAPTURE]; + + if (event == SNDRV_TIMER_EVENT_MSTOP) { + if (!dpcm_play || + dpcm_play->substream->runtime->state != + SNDRV_PCM_STATE_DRAINING) { + spin_unlock_irqrestore(&cable->lock, flags); + return; + } + } + + substream_play = (running & (1 << SNDRV_PCM_STREAM_PLAYBACK)) ? + dpcm_play->substream : NULL; + substream_capt = (running & (1 << SNDRV_PCM_STREAM_CAPTURE)) ? + dpcm_capt->substream : NULL; + valid_runtime = (running & (1 << SNDRV_PCM_STREAM_PLAYBACK)) ? + dpcm_play->substream->runtime : + dpcm_capt->substream->runtime; + + /* resolution is only valid for SNDRV_TIMER_EVENT_TICK events */ + if (event == SNDRV_TIMER_EVENT_TICK) { + /* The hardware rules guarantee that playback and capture period + * are the same. Therefore only one device has to be checked + * here. + */ + if (loopback_snd_timer_check_resolution(valid_runtime, + resolution) < 0) { + spin_unlock_irqrestore(&cable->lock, flags); + if (substream_play) + snd_pcm_stop_xrun(substream_play); + if (substream_capt) + snd_pcm_stop_xrun(substream_capt); + return; + } + } + + elapsed_bytes = frames_to_bytes(valid_runtime, + valid_runtime->period_size); + /* The same timer interrupt is used for playback and capture device */ + if ((running & (1 << SNDRV_PCM_STREAM_PLAYBACK)) && + (running & (1 << SNDRV_PCM_STREAM_CAPTURE))) { + copy_play_buf(dpcm_play, dpcm_capt, elapsed_bytes); + bytepos_finish(dpcm_play, elapsed_bytes); + bytepos_finish(dpcm_capt, elapsed_bytes); + } else if (running & (1 << SNDRV_PCM_STREAM_PLAYBACK)) { + bytepos_finish(dpcm_play, elapsed_bytes); + } else if (running & (1 << SNDRV_PCM_STREAM_CAPTURE)) { + clear_capture_buf(dpcm_capt, elapsed_bytes); + bytepos_finish(dpcm_capt, elapsed_bytes); + } + spin_unlock_irqrestore(&cable->lock, flags); + + if (substream_play) + snd_pcm_period_elapsed(substream_play); + if (substream_capt) + snd_pcm_period_elapsed(substream_capt); +} + +static void loopback_snd_timer_function(struct snd_timer_instance *timeri, + unsigned long resolution, + unsigned long ticks) +{ + struct loopback_cable *cable = timeri->callback_data; + + loopback_snd_timer_period_elapsed(cable, SNDRV_TIMER_EVENT_TICK, + resolution); +} + +static void loopback_snd_timer_work(struct work_struct *work) +{ + struct loopback_cable *cable; + + cable = container_of(work, struct loopback_cable, snd_timer.event_work); + loopback_snd_timer_period_elapsed(cable, SNDRV_TIMER_EVENT_MSTOP, 0); +} + +static void loopback_snd_timer_event(struct snd_timer_instance *timeri, + int event, + struct timespec64 *tstamp, + unsigned long resolution) +{ + /* Do not lock cable->lock here because timer->lock is already hold. + * There are other functions which first lock cable->lock and than + * timer->lock e.g. + * loopback_trigger() + * spin_lock(&cable->lock) + * loopback_snd_timer_start() + * snd_timer_start() + * spin_lock(&timer->lock) + * Therefore when using the oposit order of locks here it could result + * in a deadlock. + */ + + if (event == SNDRV_TIMER_EVENT_MSTOP) { + struct loopback_cable *cable = timeri->callback_data; + + /* sound card of the timer was stopped. Therefore there will not + * be any further timer callbacks. Due to this forward audio + * data from here if in draining state. When still in running + * state the streaming will be aborted by the usual timeout. It + * should not be aborted here because may be the timer sound + * card does only a recovery and the timer is back soon. + * This work triggers loopback_snd_timer_work() + */ + schedule_work(&cable->snd_timer.event_work); + } +} + +static void loopback_jiffies_timer_dpcm_info(struct loopback_pcm *dpcm, + struct snd_info_buffer *buffer) +{ + snd_iprintf(buffer, " update_pending:\t%u\n", + dpcm->period_update_pending); + snd_iprintf(buffer, " irq_pos:\t\t%u\n", dpcm->irq_pos); + snd_iprintf(buffer, " period_frac:\t%u\n", dpcm->period_size_frac); + snd_iprintf(buffer, " last_jiffies:\t%lu (%lu)\n", + dpcm->last_jiffies, jiffies); + snd_iprintf(buffer, " timer_expires:\t%lu\n", dpcm->timer.expires); +} + +static void loopback_snd_timer_dpcm_info(struct loopback_pcm *dpcm, + struct snd_info_buffer *buffer) +{ + struct loopback_cable *cable = dpcm->cable; + + snd_iprintf(buffer, " sound timer:\thw:%d,%d,%d\n", + cable->snd_timer.id.card, + cable->snd_timer.id.device, + cable->snd_timer.id.subdevice); + snd_iprintf(buffer, " timer open:\t\t%s\n", + (cable->snd_timer.stream == SNDRV_PCM_STREAM_CAPTURE) ? + "capture" : "playback"); +} + +static snd_pcm_uframes_t loopback_pointer(struct snd_pcm_substream *substream) +{ + struct snd_pcm_runtime *runtime = substream->runtime; + struct loopback_pcm *dpcm = runtime->private_data; + snd_pcm_uframes_t pos; + + spin_lock(&dpcm->cable->lock); + if (dpcm->cable->ops->pos_update) + dpcm->cable->ops->pos_update(dpcm->cable); + pos = dpcm->buf_pos; + spin_unlock(&dpcm->cable->lock); + return bytes_to_frames(runtime, pos); +} + +static const struct snd_pcm_hardware loopback_pcm_hardware = +{ + .info = (SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_MMAP | + SNDRV_PCM_INFO_MMAP_VALID | SNDRV_PCM_INFO_PAUSE | + SNDRV_PCM_INFO_RESUME), + .formats = (SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S16_BE | + SNDRV_PCM_FMTBIT_S24_LE | SNDRV_PCM_FMTBIT_S24_BE | + SNDRV_PCM_FMTBIT_S24_3LE | SNDRV_PCM_FMTBIT_S24_3BE | + SNDRV_PCM_FMTBIT_S32_LE | SNDRV_PCM_FMTBIT_S32_BE | + SNDRV_PCM_FMTBIT_FLOAT_LE | SNDRV_PCM_FMTBIT_FLOAT_BE), + .rates = SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_8000_192000, + .rate_min = 8000, + .rate_max = 192000, + .channels_min = 1, + .channels_max = 32, + .buffer_bytes_max = 2 * 1024 * 1024, + .period_bytes_min = 64, + /* note check overflow in frac_pos() using pcm_rate_shift before + changing period_bytes_max value */ + .period_bytes_max = 1024 * 1024, + .periods_min = 1, + .periods_max = 1024, + .fifo_size = 0, +}; + +static void loopback_runtime_free(struct snd_pcm_runtime *runtime) +{ + struct loopback_pcm *dpcm = runtime->private_data; + kfree(dpcm); +} + +static int loopback_hw_free(struct snd_pcm_substream *substream) +{ + struct snd_pcm_runtime *runtime = substream->runtime; + struct loopback_pcm *dpcm = runtime->private_data; + struct loopback_cable *cable = dpcm->cable; + + mutex_lock(&dpcm->loopback->cable_lock); + cable->valid &= ~(1 << substream->stream); + mutex_unlock(&dpcm->loopback->cable_lock); + return 0; +} + +static unsigned int get_cable_index(struct snd_pcm_substream *substream) +{ + if (!substream->pcm->device) + return substream->stream; + else + return !substream->stream; +} + +static int rule_format(struct snd_pcm_hw_params *params, + struct snd_pcm_hw_rule *rule) +{ + struct loopback_pcm *dpcm = rule->private; + struct loopback_cable *cable = dpcm->cable; + struct snd_mask m; + + snd_mask_none(&m); + mutex_lock(&dpcm->loopback->cable_lock); + m.bits[0] = (u_int32_t)cable->hw.formats; + m.bits[1] = (u_int32_t)(cable->hw.formats >> 32); + mutex_unlock(&dpcm->loopback->cable_lock); + return snd_mask_refine(hw_param_mask(params, rule->var), &m); +} + +static int rule_rate(struct snd_pcm_hw_params *params, + struct snd_pcm_hw_rule *rule) +{ + struct loopback_pcm *dpcm = rule->private; + struct loopback_cable *cable = dpcm->cable; + struct snd_interval t; + + mutex_lock(&dpcm->loopback->cable_lock); + t.min = cable->hw.rate_min; + t.max = cable->hw.rate_max; + mutex_unlock(&dpcm->loopback->cable_lock); + t.openmin = t.openmax = 0; + t.integer = 0; + return snd_interval_refine(hw_param_interval(params, rule->var), &t); +} + +static int rule_channels(struct snd_pcm_hw_params *params, + struct snd_pcm_hw_rule *rule) +{ + struct loopback_pcm *dpcm = rule->private; + struct loopback_cable *cable = dpcm->cable; + struct snd_interval t; + + mutex_lock(&dpcm->loopback->cable_lock); + t.min = cable->hw.channels_min; + t.max = cable->hw.channels_max; + mutex_unlock(&dpcm->loopback->cable_lock); + t.openmin = t.openmax = 0; + t.integer = 0; + return snd_interval_refine(hw_param_interval(params, rule->var), &t); +} + +static int rule_period_bytes(struct snd_pcm_hw_params *params, + struct snd_pcm_hw_rule *rule) +{ + struct loopback_pcm *dpcm = rule->private; + struct loopback_cable *cable = dpcm->cable; + struct snd_interval t; + + mutex_lock(&dpcm->loopback->cable_lock); + t.min = cable->hw.period_bytes_min; + t.max = cable->hw.period_bytes_max; + mutex_unlock(&dpcm->loopback->cable_lock); + t.openmin = 0; + t.openmax = 0; + t.integer = 0; + return snd_interval_refine(hw_param_interval(params, rule->var), &t); +} + +static void free_cable(struct snd_pcm_substream *substream) +{ + struct loopback *loopback = substream->private_data; + int dev = get_cable_index(substream); + struct loopback_cable *cable; + + cable = loopback->cables[substream->number][dev]; + if (!cable) + return; + if (cable->streams[!substream->stream]) { + /* other stream is still alive */ + spin_lock_irq(&cable->lock); + cable->streams[substream->stream] = NULL; + spin_unlock_irq(&cable->lock); + } else { + struct loopback_pcm *dpcm = substream->runtime->private_data; + + if (cable->ops && cable->ops->close_cable && dpcm) + cable->ops->close_cable(dpcm); + /* free the cable */ + loopback->cables[substream->number][dev] = NULL; + kfree(cable); + } +} + +static int loopback_jiffies_timer_open(struct loopback_pcm *dpcm) +{ + timer_setup(&dpcm->timer, loopback_jiffies_timer_function, 0); + + return 0; +} + +static const struct loopback_ops loopback_jiffies_timer_ops = { + .open = loopback_jiffies_timer_open, + .start = loopback_jiffies_timer_start, + .stop = loopback_jiffies_timer_stop, + .stop_sync = loopback_jiffies_timer_stop_sync, + .close_substream = loopback_jiffies_timer_stop_sync, + .pos_update = loopback_jiffies_timer_pos_update, + .dpcm_info = loopback_jiffies_timer_dpcm_info, +}; + +static int loopback_parse_timer_id(const char *str, + struct snd_timer_id *tid) +{ + /* [<pref>:](<card name>|<card idx>)[{.,}<dev idx>[{.,}<subdev idx>]] */ + const char * const sep_dev = ".,"; + const char * const sep_pref = ":"; + const char *name = str; + char *sep, save = '\0'; + int card_idx = 0, dev = 0, subdev = 0; + int err; + + sep = strpbrk(str, sep_pref); + if (sep) + name = sep + 1; + sep = strpbrk(name, sep_dev); + if (sep) { + save = *sep; + *sep = '\0'; + } + err = kstrtoint(name, 0, &card_idx); + if (err == -EINVAL) { + /* Must be the name, not number */ + for (card_idx = 0; card_idx < snd_ecards_limit; card_idx++) { + struct snd_card *card = snd_card_ref(card_idx); + + if (card) { + if (!strcmp(card->id, name)) + err = 0; + snd_card_unref(card); + } + if (!err) + break; + } + } + if (sep) { + *sep = save; + if (!err) { + char *sep2, save2 = '\0'; + + sep2 = strpbrk(sep + 1, sep_dev); + if (sep2) { + save2 = *sep2; + *sep2 = '\0'; + } + err = kstrtoint(sep + 1, 0, &dev); + if (sep2) { + *sep2 = save2; + if (!err) + err = kstrtoint(sep2 + 1, 0, &subdev); + } + } + } + if (!err && tid) { + tid->card = card_idx; + tid->device = dev; + tid->subdevice = subdev; + } + return err; +} + +/* call in loopback->cable_lock */ +static int loopback_snd_timer_open(struct loopback_pcm *dpcm) +{ + int err = 0; + struct snd_timer_id tid = { + .dev_class = SNDRV_TIMER_CLASS_PCM, + .dev_sclass = SNDRV_TIMER_SCLASS_APPLICATION, + }; + struct snd_timer_instance *timeri; + struct loopback_cable *cable = dpcm->cable; + + /* check if timer was already opened. It is only opened once + * per playback and capture subdevice (aka cable). + */ + if (cable->snd_timer.instance) + goto exit; + + err = loopback_parse_timer_id(dpcm->loopback->timer_source, &tid); + if (err < 0) { + pcm_err(dpcm->substream->pcm, + "Parsing timer source \'%s\' failed with %d", + dpcm->loopback->timer_source, err); + goto exit; + } + + cable->snd_timer.stream = dpcm->substream->stream; + cable->snd_timer.id = tid; + + timeri = snd_timer_instance_new(dpcm->loopback->card->id); + if (!timeri) { + err = -ENOMEM; + goto exit; + } + /* The callback has to be called from another work. If + * SNDRV_TIMER_IFLG_FAST is specified it will be called from the + * snd_pcm_period_elapsed() call of the selected sound card. + * snd_pcm_period_elapsed() helds snd_pcm_stream_lock_irqsave(). + * Due to our callback loopback_snd_timer_function() also calls + * snd_pcm_period_elapsed() which calls snd_pcm_stream_lock_irqsave(). + * This would end up in a dead lock. + */ + timeri->flags |= SNDRV_TIMER_IFLG_AUTO; + timeri->callback = loopback_snd_timer_function; + timeri->callback_data = (void *)cable; + timeri->ccallback = loopback_snd_timer_event; + + /* initialise a work used for draining */ + INIT_WORK(&cable->snd_timer.event_work, loopback_snd_timer_work); + + /* The mutex loopback->cable_lock is kept locked. + * Therefore snd_timer_open() cannot be called a second time + * by the other device of the same cable. + * Therefore the following issue cannot happen: + * [proc1] Call loopback_timer_open() -> + * Unlock cable->lock for snd_timer_close/open() call + * [proc2] Call loopback_timer_open() -> snd_timer_open(), + * snd_timer_start() + * [proc1] Call snd_timer_open() and overwrite running timer + * instance + */ + err = snd_timer_open(timeri, &cable->snd_timer.id, current->pid); + if (err < 0) { + pcm_err(dpcm->substream->pcm, + "snd_timer_open (%d,%d,%d) failed with %d", + cable->snd_timer.id.card, + cable->snd_timer.id.device, + cable->snd_timer.id.subdevice, + err); + snd_timer_instance_free(timeri); + goto exit; + } + + cable->snd_timer.instance = timeri; + +exit: + return err; +} + +/* stop_sync() is not required for sound timer because it does not need to be + * restarted in loopback_prepare() on Xrun recovery + */ +static const struct loopback_ops loopback_snd_timer_ops = { + .open = loopback_snd_timer_open, + .start = loopback_snd_timer_start, + .stop = loopback_snd_timer_stop, + .close_cable = loopback_snd_timer_close_cable, + .dpcm_info = loopback_snd_timer_dpcm_info, +}; + +static int loopback_open(struct snd_pcm_substream *substream) +{ + struct snd_pcm_runtime *runtime = substream->runtime; + struct loopback *loopback = substream->private_data; + struct loopback_pcm *dpcm; + struct loopback_cable *cable = NULL; + int err = 0; + int dev = get_cable_index(substream); + + mutex_lock(&loopback->cable_lock); + dpcm = kzalloc(sizeof(*dpcm), GFP_KERNEL); + if (!dpcm) { + err = -ENOMEM; + goto unlock; + } + dpcm->loopback = loopback; + dpcm->substream = substream; + + cable = loopback->cables[substream->number][dev]; + if (!cable) { + cable = kzalloc(sizeof(*cable), GFP_KERNEL); + if (!cable) { + err = -ENOMEM; + goto unlock; + } + spin_lock_init(&cable->lock); + cable->hw = loopback_pcm_hardware; + if (loopback->timer_source) + cable->ops = &loopback_snd_timer_ops; + else + cable->ops = &loopback_jiffies_timer_ops; + loopback->cables[substream->number][dev] = cable; + } + dpcm->cable = cable; + runtime->private_data = dpcm; + + if (cable->ops->open) { + err = cable->ops->open(dpcm); + if (err < 0) + goto unlock; + } + + snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS); + + /* use dynamic rules based on actual runtime->hw values */ + /* note that the default rules created in the PCM midlevel code */ + /* are cached -> they do not reflect the actual state */ + err = snd_pcm_hw_rule_add(runtime, 0, + SNDRV_PCM_HW_PARAM_FORMAT, + rule_format, dpcm, + SNDRV_PCM_HW_PARAM_FORMAT, -1); + if (err < 0) + goto unlock; + err = snd_pcm_hw_rule_add(runtime, 0, + SNDRV_PCM_HW_PARAM_RATE, + rule_rate, dpcm, + SNDRV_PCM_HW_PARAM_RATE, -1); + if (err < 0) + goto unlock; + err = snd_pcm_hw_rule_add(runtime, 0, + SNDRV_PCM_HW_PARAM_CHANNELS, + rule_channels, dpcm, + SNDRV_PCM_HW_PARAM_CHANNELS, -1); + if (err < 0) + goto unlock; + + /* In case of sound timer the period time of both devices of the same + * loop has to be the same. + * This rule only takes effect if a sound timer was chosen + */ + if (cable->snd_timer.instance) { + err = snd_pcm_hw_rule_add(runtime, 0, + SNDRV_PCM_HW_PARAM_PERIOD_BYTES, + rule_period_bytes, dpcm, + SNDRV_PCM_HW_PARAM_PERIOD_BYTES, -1); + if (err < 0) + goto unlock; + } + + /* loopback_runtime_free() has not to be called if kfree(dpcm) was + * already called here. Otherwise it will end up with a double free. + */ + runtime->private_free = loopback_runtime_free; + if (get_notify(dpcm)) + runtime->hw = loopback_pcm_hardware; + else + runtime->hw = cable->hw; + + spin_lock_irq(&cable->lock); + cable->streams[substream->stream] = dpcm; + spin_unlock_irq(&cable->lock); + + unlock: + if (err < 0) { + free_cable(substream); + kfree(dpcm); + } + mutex_unlock(&loopback->cable_lock); + return err; +} + +static int loopback_close(struct snd_pcm_substream *substream) +{ + struct loopback *loopback = substream->private_data; + struct loopback_pcm *dpcm = substream->runtime->private_data; + int err = 0; + + if (dpcm->cable->ops->close_substream) + err = dpcm->cable->ops->close_substream(dpcm); + mutex_lock(&loopback->cable_lock); + free_cable(substream); + mutex_unlock(&loopback->cable_lock); + return err; +} + +static const struct snd_pcm_ops loopback_pcm_ops = { + .open = loopback_open, + .close = loopback_close, + .hw_free = loopback_hw_free, + .prepare = loopback_prepare, + .trigger = loopback_trigger, + .pointer = loopback_pointer, +}; + +static int loopback_pcm_new(struct loopback *loopback, + int device, int substreams) +{ + struct snd_pcm *pcm; + int err; + + err = snd_pcm_new(loopback->card, "Loopback PCM", device, + substreams, substreams, &pcm); + if (err < 0) + return err; + snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &loopback_pcm_ops); + snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &loopback_pcm_ops); + snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_VMALLOC, NULL, 0, 0); + + pcm->private_data = loopback; + pcm->info_flags = 0; + strcpy(pcm->name, "Loopback PCM"); + + loopback->pcm[device] = pcm; + return 0; +} + +static int loopback_rate_shift_info(struct snd_kcontrol *kcontrol, + struct snd_ctl_elem_info *uinfo) +{ + uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER; + uinfo->count = 1; + uinfo->value.integer.min = 80000; + uinfo->value.integer.max = 120000; + uinfo->value.integer.step = 1; + return 0; +} + +static int loopback_rate_shift_get(struct snd_kcontrol *kcontrol, + struct snd_ctl_elem_value *ucontrol) +{ + struct loopback *loopback = snd_kcontrol_chip(kcontrol); + + mutex_lock(&loopback->cable_lock); + ucontrol->value.integer.value[0] = + loopback->setup[kcontrol->id.subdevice] + [kcontrol->id.device].rate_shift; + mutex_unlock(&loopback->cable_lock); + return 0; +} + +static int loopback_rate_shift_put(struct snd_kcontrol *kcontrol, + struct snd_ctl_elem_value *ucontrol) +{ + struct loopback *loopback = snd_kcontrol_chip(kcontrol); + unsigned int val; + int change = 0; + + val = ucontrol->value.integer.value[0]; + if (val < 80000) + val = 80000; + if (val > 120000) + val = 120000; + mutex_lock(&loopback->cable_lock); + if (val != loopback->setup[kcontrol->id.subdevice] + [kcontrol->id.device].rate_shift) { + loopback->setup[kcontrol->id.subdevice] + [kcontrol->id.device].rate_shift = val; + change = 1; + } + mutex_unlock(&loopback->cable_lock); + return change; +} + +static int loopback_notify_get(struct snd_kcontrol *kcontrol, + struct snd_ctl_elem_value *ucontrol) +{ + struct loopback *loopback = snd_kcontrol_chip(kcontrol); + + mutex_lock(&loopback->cable_lock); + ucontrol->value.integer.value[0] = + loopback->setup[kcontrol->id.subdevice] + [kcontrol->id.device].notify; + mutex_unlock(&loopback->cable_lock); + return 0; +} + +static int loopback_notify_put(struct snd_kcontrol *kcontrol, + struct snd_ctl_elem_value *ucontrol) +{ + struct loopback *loopback = snd_kcontrol_chip(kcontrol); + unsigned int val; + int change = 0; + + val = ucontrol->value.integer.value[0] ? 1 : 0; + mutex_lock(&loopback->cable_lock); + if (val != loopback->setup[kcontrol->id.subdevice] + [kcontrol->id.device].notify) { + loopback->setup[kcontrol->id.subdevice] + [kcontrol->id.device].notify = val; + change = 1; + } + mutex_unlock(&loopback->cable_lock); + return change; +} + +static int loopback_active_get(struct snd_kcontrol *kcontrol, + struct snd_ctl_elem_value *ucontrol) +{ + struct loopback *loopback = snd_kcontrol_chip(kcontrol); + struct loopback_cable *cable; + + unsigned int val = 0; + + mutex_lock(&loopback->cable_lock); + cable = loopback->cables[kcontrol->id.subdevice][kcontrol->id.device ^ 1]; + if (cable != NULL) { + unsigned int running = cable->running ^ cable->pause; + + val = (running & (1 << SNDRV_PCM_STREAM_PLAYBACK)) ? 1 : 0; + } + mutex_unlock(&loopback->cable_lock); + ucontrol->value.integer.value[0] = val; + return 0; +} + +static int loopback_format_info(struct snd_kcontrol *kcontrol, + struct snd_ctl_elem_info *uinfo) +{ + uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER; + uinfo->count = 1; + uinfo->value.integer.min = 0; + uinfo->value.integer.max = (__force int)SNDRV_PCM_FORMAT_LAST; + uinfo->value.integer.step = 1; + return 0; +} + +static int loopback_format_get(struct snd_kcontrol *kcontrol, + struct snd_ctl_elem_value *ucontrol) +{ + struct loopback *loopback = snd_kcontrol_chip(kcontrol); + + ucontrol->value.integer.value[0] = + (__force int)loopback->setup[kcontrol->id.subdevice] + [kcontrol->id.device].format; + return 0; +} + +static int loopback_rate_info(struct snd_kcontrol *kcontrol, + struct snd_ctl_elem_info *uinfo) +{ + uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER; + uinfo->count = 1; + uinfo->value.integer.min = 0; + uinfo->value.integer.max = 192000; + uinfo->value.integer.step = 1; + return 0; +} + +static int loopback_rate_get(struct snd_kcontrol *kcontrol, + struct snd_ctl_elem_value *ucontrol) +{ + struct loopback *loopback = snd_kcontrol_chip(kcontrol); + + mutex_lock(&loopback->cable_lock); + ucontrol->value.integer.value[0] = + loopback->setup[kcontrol->id.subdevice] + [kcontrol->id.device].rate; + mutex_unlock(&loopback->cable_lock); + return 0; +} + +static int loopback_channels_info(struct snd_kcontrol *kcontrol, + struct snd_ctl_elem_info *uinfo) +{ + uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER; + uinfo->count = 1; + uinfo->value.integer.min = 1; + uinfo->value.integer.max = 1024; + uinfo->value.integer.step = 1; + return 0; +} + +static int loopback_channels_get(struct snd_kcontrol *kcontrol, + struct snd_ctl_elem_value *ucontrol) +{ + struct loopback *loopback = snd_kcontrol_chip(kcontrol); + + mutex_lock(&loopback->cable_lock); + ucontrol->value.integer.value[0] = + loopback->setup[kcontrol->id.subdevice] + [kcontrol->id.device].channels; + mutex_unlock(&loopback->cable_lock); + return 0; +} + +static const struct snd_kcontrol_new loopback_controls[] = { +{ + .iface = SNDRV_CTL_ELEM_IFACE_PCM, + .name = "PCM Rate Shift 100000", + .info = loopback_rate_shift_info, + .get = loopback_rate_shift_get, + .put = loopback_rate_shift_put, +}, +{ + .iface = SNDRV_CTL_ELEM_IFACE_PCM, + .name = "PCM Notify", + .info = snd_ctl_boolean_mono_info, + .get = loopback_notify_get, + .put = loopback_notify_put, +}, +#define ACTIVE_IDX 2 +{ + .access = SNDRV_CTL_ELEM_ACCESS_READ, + .iface = SNDRV_CTL_ELEM_IFACE_PCM, + .name = "PCM Slave Active", + .info = snd_ctl_boolean_mono_info, + .get = loopback_active_get, +}, +#define FORMAT_IDX 3 +{ + .access = SNDRV_CTL_ELEM_ACCESS_READ, + .iface = SNDRV_CTL_ELEM_IFACE_PCM, + .name = "PCM Slave Format", + .info = loopback_format_info, + .get = loopback_format_get +}, +#define RATE_IDX 4 +{ + .access = SNDRV_CTL_ELEM_ACCESS_READ, + .iface = SNDRV_CTL_ELEM_IFACE_PCM, + .name = "PCM Slave Rate", + .info = loopback_rate_info, + .get = loopback_rate_get +}, +#define CHANNELS_IDX 5 +{ + .access = SNDRV_CTL_ELEM_ACCESS_READ, + .iface = SNDRV_CTL_ELEM_IFACE_PCM, + .name = "PCM Slave Channels", + .info = loopback_channels_info, + .get = loopback_channels_get +} +}; + +static int loopback_mixer_new(struct loopback *loopback, int notify) +{ + struct snd_card *card = loopback->card; + struct snd_pcm *pcm; + struct snd_kcontrol *kctl; + struct loopback_setup *setup; + int err, dev, substr, substr_count, idx; + + strcpy(card->mixername, "Loopback Mixer"); + for (dev = 0; dev < 2; dev++) { + pcm = loopback->pcm[dev]; + substr_count = + pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream_count; + for (substr = 0; substr < substr_count; substr++) { + setup = &loopback->setup[substr][dev]; + setup->notify = notify; + setup->rate_shift = NO_PITCH; + setup->format = SNDRV_PCM_FORMAT_S16_LE; + setup->rate = 48000; + setup->channels = 2; + for (idx = 0; idx < ARRAY_SIZE(loopback_controls); + idx++) { + kctl = snd_ctl_new1(&loopback_controls[idx], + loopback); + if (!kctl) + return -ENOMEM; + kctl->id.device = dev; + kctl->id.subdevice = substr; + + /* Add the control before copying the id so that + * the numid field of the id is set in the copy. + */ + err = snd_ctl_add(card, kctl); + if (err < 0) + return err; + + switch (idx) { + case ACTIVE_IDX: + setup->active_id = kctl->id; + break; + case FORMAT_IDX: + setup->format_id = kctl->id; + break; + case RATE_IDX: + setup->rate_id = kctl->id; + break; + case CHANNELS_IDX: + setup->channels_id = kctl->id; + break; + default: + break; + } + } + } + } + return 0; +} + +static void print_dpcm_info(struct snd_info_buffer *buffer, + struct loopback_pcm *dpcm, + const char *id) +{ + snd_iprintf(buffer, " %s\n", id); + if (dpcm == NULL) { + snd_iprintf(buffer, " inactive\n"); + return; + } + snd_iprintf(buffer, " buffer_size:\t%u\n", dpcm->pcm_buffer_size); + snd_iprintf(buffer, " buffer_pos:\t\t%u\n", dpcm->buf_pos); + snd_iprintf(buffer, " silent_size:\t%u\n", dpcm->silent_size); + snd_iprintf(buffer, " period_size:\t%u\n", dpcm->pcm_period_size); + snd_iprintf(buffer, " bytes_per_sec:\t%u\n", dpcm->pcm_bps); + snd_iprintf(buffer, " sample_align:\t%u\n", dpcm->pcm_salign); + snd_iprintf(buffer, " rate_shift:\t\t%u\n", dpcm->pcm_rate_shift); + if (dpcm->cable->ops->dpcm_info) + dpcm->cable->ops->dpcm_info(dpcm, buffer); +} + +static void print_substream_info(struct snd_info_buffer *buffer, + struct loopback *loopback, + int sub, + int num) +{ + struct loopback_cable *cable = loopback->cables[sub][num]; + + snd_iprintf(buffer, "Cable %i substream %i:\n", num, sub); + if (cable == NULL) { + snd_iprintf(buffer, " inactive\n"); + return; + } + snd_iprintf(buffer, " valid: %u\n", cable->valid); + snd_iprintf(buffer, " running: %u\n", cable->running); + snd_iprintf(buffer, " pause: %u\n", cable->pause); + print_dpcm_info(buffer, cable->streams[0], "Playback"); + print_dpcm_info(buffer, cable->streams[1], "Capture"); +} + +static void print_cable_info(struct snd_info_entry *entry, + struct snd_info_buffer *buffer) +{ + struct loopback *loopback = entry->private_data; + int sub, num; + + mutex_lock(&loopback->cable_lock); + num = entry->name[strlen(entry->name)-1]; + num = num == '0' ? 0 : 1; + for (sub = 0; sub < MAX_PCM_SUBSTREAMS; sub++) + print_substream_info(buffer, loopback, sub, num); + mutex_unlock(&loopback->cable_lock); +} + +static int loopback_cable_proc_new(struct loopback *loopback, int cidx) +{ + char name[32]; + + snprintf(name, sizeof(name), "cable#%d", cidx); + return snd_card_ro_proc_new(loopback->card, name, loopback, + print_cable_info); +} + +static void loopback_set_timer_source(struct loopback *loopback, + const char *value) +{ + if (loopback->timer_source) { + devm_kfree(loopback->card->dev, loopback->timer_source); + loopback->timer_source = NULL; + } + if (value && *value) + loopback->timer_source = devm_kstrdup(loopback->card->dev, + value, GFP_KERNEL); +} + +static void print_timer_source_info(struct snd_info_entry *entry, + struct snd_info_buffer *buffer) +{ + struct loopback *loopback = entry->private_data; + + mutex_lock(&loopback->cable_lock); + snd_iprintf(buffer, "%s\n", + loopback->timer_source ? loopback->timer_source : ""); + mutex_unlock(&loopback->cable_lock); +} + +static void change_timer_source_info(struct snd_info_entry *entry, + struct snd_info_buffer *buffer) +{ + struct loopback *loopback = entry->private_data; + char line[64]; + + mutex_lock(&loopback->cable_lock); + if (!snd_info_get_line(buffer, line, sizeof(line))) + loopback_set_timer_source(loopback, strim(line)); + mutex_unlock(&loopback->cable_lock); +} + +static int loopback_timer_source_proc_new(struct loopback *loopback) +{ + return snd_card_rw_proc_new(loopback->card, "timer_source", loopback, + print_timer_source_info, + change_timer_source_info); +} + +static int loopback_probe(struct platform_device *devptr) +{ + struct snd_card *card; + struct loopback *loopback; + int dev = devptr->id; + int err; + + err = snd_devm_card_new(&devptr->dev, index[dev], id[dev], THIS_MODULE, + sizeof(struct loopback), &card); + if (err < 0) + return err; + loopback = card->private_data; + + if (pcm_substreams[dev] < 1) + pcm_substreams[dev] = 1; + if (pcm_substreams[dev] > MAX_PCM_SUBSTREAMS) + pcm_substreams[dev] = MAX_PCM_SUBSTREAMS; + + loopback->card = card; + loopback_set_timer_source(loopback, timer_source[dev]); + + mutex_init(&loopback->cable_lock); + + err = loopback_pcm_new(loopback, 0, pcm_substreams[dev]); + if (err < 0) + return err; + err = loopback_pcm_new(loopback, 1, pcm_substreams[dev]); + if (err < 0) + return err; + err = loopback_mixer_new(loopback, pcm_notify[dev] ? 1 : 0); + if (err < 0) + return err; + loopback_cable_proc_new(loopback, 0); + loopback_cable_proc_new(loopback, 1); + loopback_timer_source_proc_new(loopback); + strcpy(card->driver, "Loopback"); + strcpy(card->shortname, "Loopback"); + sprintf(card->longname, "Loopback %i", dev + 1); + err = snd_card_register(card); + if (err < 0) + return err; + platform_set_drvdata(devptr, card); + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int loopback_suspend(struct device *pdev) +{ + struct snd_card *card = dev_get_drvdata(pdev); + + snd_power_change_state(card, SNDRV_CTL_POWER_D3hot); + return 0; +} + +static int loopback_resume(struct device *pdev) +{ + struct snd_card *card = dev_get_drvdata(pdev); + + snd_power_change_state(card, SNDRV_CTL_POWER_D0); + return 0; +} + +static SIMPLE_DEV_PM_OPS(loopback_pm, loopback_suspend, loopback_resume); +#define LOOPBACK_PM_OPS &loopback_pm +#else +#define LOOPBACK_PM_OPS NULL +#endif + +#define SND_LOOPBACK_DRIVER "snd_aloop" + +static struct platform_driver loopback_driver = { + .probe = loopback_probe, + .driver = { + .name = SND_LOOPBACK_DRIVER, + .pm = LOOPBACK_PM_OPS, + }, +}; + +static void loopback_unregister_all(void) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(devices); ++i) + platform_device_unregister(devices[i]); + platform_driver_unregister(&loopback_driver); +} + +static int __init alsa_card_loopback_init(void) +{ + int i, err, cards; + + err = platform_driver_register(&loopback_driver); + if (err < 0) + return err; + + + cards = 0; + for (i = 0; i < SNDRV_CARDS; i++) { + struct platform_device *device; + if (!enable[i]) + continue; + device = platform_device_register_simple(SND_LOOPBACK_DRIVER, + i, NULL, 0); + if (IS_ERR(device)) + continue; + if (!platform_get_drvdata(device)) { + platform_device_unregister(device); + continue; + } + devices[i] = device; + cards++; + } + if (!cards) { +#ifdef MODULE + printk(KERN_ERR "aloop: No loopback enabled\n"); +#endif + loopback_unregister_all(); + return -ENODEV; + } + return 0; +} + +static void __exit alsa_card_loopback_exit(void) +{ + loopback_unregister_all(); +} + +module_init(alsa_card_loopback_init) +module_exit(alsa_card_loopback_exit) |