Kernel/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2025-01-06 05:06:29 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity
93d7d38fa6
linux-stable/sound/drivers/aloop.c
Pavel Hofman 93d7d38fa6 ALSA: aloop: add DSD formats 
The snd-aloop loopback driver does not modify or access the actual samples
in any way, defines no volume or mute controls, it's strictly bitperfect.
Therefore DSD formats can be supported without any modification.

Add all DSD formats to the list of supported formats.

Signed-off-by: Pavel Hofman <pavel.hofman@ivitera.com>
Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Message-ID: <20240416121726.628679-2-pavel.hofman@ivitera.com>
2024-04-18 09:30:25 +02:00

1915 lines
54 KiB
C
Raw Blame History

// 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;
snd_pcm_access_t access;
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 snd_ctl_elem_id access_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;
/* size of per channel buffer in case of non-interleaved access */
unsigned int channel_buf_n;
};
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 bool is_access_interleaved(snd_pcm_access_t access)
{
switch (access) {
case SNDRV_PCM_ACCESS_MMAP_INTERLEAVED:
case SNDRV_PCM_ACCESS_RW_INTERLEAVED:
return true;
default:
return false;
}
};
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 ||
is_access_interleaved(runtime->access) !=
is_access_interleaved(cruntime->access);
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;
}
if (is_access_interleaved(setup->access) !=
is_access_interleaved(runtime->access)) {
snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
&setup->access_id);
setup->access = runtime->access;
}
}
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);
dpcm->channel_buf_n = dpcm->pcm_buffer_size / runtime->channels;
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_part_n(struct loopback_pcm *play, struct loopback_pcm *capt,
unsigned int size, unsigned int src_off, unsigned int dst_off)
{
unsigned int channels = capt->substream->runtime->channels;
unsigned int size_p_ch = size / channels;
unsigned int src_off_ch = src_off / channels;
unsigned int dst_off_ch = dst_off / channels;
int i;
for (i = 0; i < channels; i++) {
memcpy(capt->substream->runtime->dma_area + capt->channel_buf_n * i + dst_off_ch,
play->substream->runtime->dma_area + play->channel_buf_n * i + src_off_ch,
size_p_ch);
}
}
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;
if (!is_access_interleaved(runtime->access))
copy_play_buf_part_n(play, capt, size, src_off, dst_off);
else
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 | SNDRV_PCM_INFO_NONINTERLEAVED),
.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 |
SNDRV_PCM_FMTBIT_DSD_U8 |
SNDRV_PCM_FMTBIT_DSD_U16_LE | SNDRV_PCM_FMTBIT_DSD_U16_BE |
SNDRV_PCM_FMTBIT_DSD_U32_LE | SNDRV_PCM_FMTBIT_DSD_U32_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 int loopback_access_info(struct snd_kcontrol *kcontrol,
struct snd_ctl_elem_info *uinfo)
{
const char * const texts[] = {"Interleaved", "Non-interleaved"};
return snd_ctl_enum_info(uinfo, 1, ARRAY_SIZE(texts), texts);
}
static int loopback_access_get(struct snd_kcontrol *kcontrol,
struct snd_ctl_elem_value *ucontrol)
{
struct loopback *loopback = snd_kcontrol_chip(kcontrol);
snd_pcm_access_t access;
mutex_lock(&loopback->cable_lock);
access = loopback->setup[kcontrol->id.subdevice][kcontrol->id.device].access;
ucontrol->value.enumerated.item[0] = !is_access_interleaved(access);
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
},
#define ACCESS_IDX 6
{
.access = SNDRV_CTL_ELEM_ACCESS_READ,
.iface = SNDRV_CTL_ELEM_IFACE_PCM,
.name = "PCM Slave Access Mode",
.info = loopback_access_info,
.get = loopback_access_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->access = SNDRV_PCM_ACCESS_RW_INTERLEAVED;
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;
case ACCESS_IDX:
setup->access_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;
}
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 DEFINE_SIMPLE_DEV_PM_OPS(loopback_pm, loopback_suspend, loopback_resume);
#define SND_LOOPBACK_DRIVER "snd_aloop"
static struct platform_driver loopback_driver = {
.probe = loopback_probe,
.driver = {
.name = SND_LOOPBACK_DRIVER,
.pm = &loopback_pm,
},
};
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)
Reference in New Issue View Git Blame Copy Permalink