linux-stable/sound/firewire/digi00x/digi00x-pcm.c
Takashi Sakamoto c36f8fcc58 ALSA: firewire-digi00x: use the same size of period for PCM substream in AMDTP streams
In current implementation, when opening a PCM substream, it's needed to
check whether the opposite PCM substream runs. This is to assign
effectual constraints (e.g. sampling rate) to opened PCM substream.

The number of PCM substreams and MIDI substreams on AMDTP streams in
domain is recorded in own structure. Usage of this count is an
alternative of the above check. This is better because the count is
incremented in pcm.hw_params earlier than pcm.trigger.

This idea has one issue because it's incremented for MIDI substreams as
well. In current implementation, for a case that any MIDI substream run
and a PCM substream is going to start, PCM application to start the PCM
substream can decide hardware parameters by restart packet streaming.
Just checking the substream count can brings regression.

Now AMDTP domain structure has a member for the size of PCM period in
PCM substream which starts AMDTP streams in domain. When the value has
zero and the substream count is greater than 1, it means that any MIDI
substream starts AMDTP streams in domain. Usage of the value can resolve
the above issue.

This commit replaces the check with the substream count and the value for
the size of PCM period.

I note that DOT AMDTP protocol has a quirk to use different transmission
method of IEC 61883-6 for tx/rx streams; non-blocking in tx stream and
blocking in rx stream. Although the difference of transmission method
between tx/rx streams precisely brings different timing for a certain
amount of events due to their different calculation for data blocks per
packet, it's possible to approximate enough amount of events mostly has
the same timing. Actually current ALSA IEC 61883-1/6 engine uses large
amount of data blocks for each hardware IRQ (=16 packets).

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20191007110532.30270-15-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2019-10-17 12:02:45 +02:00

358 lines
8.6 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* digi00x-pcm.c - a part of driver for Digidesign Digi 002/003 family
*
* Copyright (c) 2014-2015 Takashi Sakamoto
*/
#include "digi00x.h"
static int hw_rule_rate(struct snd_pcm_hw_params *params,
struct snd_pcm_hw_rule *rule)
{
struct snd_interval *r =
hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
const struct snd_interval *c =
hw_param_interval_c(params, SNDRV_PCM_HW_PARAM_CHANNELS);
struct snd_interval t = {
.min = UINT_MAX, .max = 0, .integer = 1,
};
unsigned int i;
for (i = 0; i < SND_DG00X_RATE_COUNT; i++) {
if (!snd_interval_test(c,
snd_dg00x_stream_pcm_channels[i]))
continue;
t.min = min(t.min, snd_dg00x_stream_rates[i]);
t.max = max(t.max, snd_dg00x_stream_rates[i]);
}
return snd_interval_refine(r, &t);
}
static int hw_rule_channels(struct snd_pcm_hw_params *params,
struct snd_pcm_hw_rule *rule)
{
struct snd_interval *c =
hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
const struct snd_interval *r =
hw_param_interval_c(params, SNDRV_PCM_HW_PARAM_RATE);
struct snd_interval t = {
.min = UINT_MAX, .max = 0, .integer = 1,
};
unsigned int i;
for (i = 0; i < SND_DG00X_RATE_COUNT; i++) {
if (!snd_interval_test(r, snd_dg00x_stream_rates[i]))
continue;
t.min = min(t.min, snd_dg00x_stream_pcm_channels[i]);
t.max = max(t.max, snd_dg00x_stream_pcm_channels[i]);
}
return snd_interval_refine(c, &t);
}
static int pcm_init_hw_params(struct snd_dg00x *dg00x,
struct snd_pcm_substream *substream)
{
struct snd_pcm_runtime *runtime = substream->runtime;
struct snd_pcm_hardware *hw = &runtime->hw;
struct amdtp_stream *s;
int err;
if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) {
substream->runtime->hw.formats = SNDRV_PCM_FMTBIT_S32;
s = &dg00x->tx_stream;
} else {
substream->runtime->hw.formats = SNDRV_PCM_FMTBIT_S32;
s = &dg00x->rx_stream;
}
hw->channels_min = 10;
hw->channels_max = 18;
hw->rates = SNDRV_PCM_RATE_44100 |
SNDRV_PCM_RATE_48000 |
SNDRV_PCM_RATE_88200 |
SNDRV_PCM_RATE_96000;
snd_pcm_limit_hw_rates(runtime);
err = snd_pcm_hw_rule_add(substream->runtime, 0,
SNDRV_PCM_HW_PARAM_CHANNELS,
hw_rule_channels, NULL,
SNDRV_PCM_HW_PARAM_RATE, -1);
if (err < 0)
return err;
err = snd_pcm_hw_rule_add(substream->runtime, 0,
SNDRV_PCM_HW_PARAM_RATE,
hw_rule_rate, NULL,
SNDRV_PCM_HW_PARAM_CHANNELS, -1);
if (err < 0)
return err;
return amdtp_dot_add_pcm_hw_constraints(s, substream->runtime);
}
static int pcm_open(struct snd_pcm_substream *substream)
{
struct snd_dg00x *dg00x = substream->private_data;
struct amdtp_domain *d = &dg00x->domain;
enum snd_dg00x_clock clock;
bool detect;
int err;
err = snd_dg00x_stream_lock_try(dg00x);
if (err < 0)
return err;
err = pcm_init_hw_params(dg00x, substream);
if (err < 0)
goto err_locked;
/* Check current clock source. */
err = snd_dg00x_stream_get_clock(dg00x, &clock);
if (err < 0)
goto err_locked;
if (clock != SND_DG00X_CLOCK_INTERNAL) {
err = snd_dg00x_stream_check_external_clock(dg00x, &detect);
if (err < 0)
goto err_locked;
if (!detect) {
err = -EBUSY;
goto err_locked;
}
}
mutex_lock(&dg00x->mutex);
// When source of clock is not internal or any stream is reserved for
// transmission of PCM frames, the available sampling rate is limited
// at current one.
if ((clock != SND_DG00X_CLOCK_INTERNAL) ||
(dg00x->substreams_counter > 0 && d->events_per_period > 0)) {
unsigned int frames_per_period = d->events_per_period;
unsigned int rate;
err = snd_dg00x_stream_get_external_rate(dg00x, &rate);
if (err < 0) {
mutex_unlock(&dg00x->mutex);
goto err_locked;
}
substream->runtime->hw.rate_min = rate;
substream->runtime->hw.rate_max = rate;
if (frames_per_period > 0) {
err = snd_pcm_hw_constraint_minmax(substream->runtime,
SNDRV_PCM_HW_PARAM_PERIOD_SIZE,
frames_per_period, frames_per_period);
if (err < 0) {
mutex_unlock(&dg00x->mutex);
goto err_locked;
}
}
}
mutex_unlock(&dg00x->mutex);
snd_pcm_set_sync(substream);
return 0;
err_locked:
snd_dg00x_stream_lock_release(dg00x);
return err;
}
static int pcm_close(struct snd_pcm_substream *substream)
{
struct snd_dg00x *dg00x = substream->private_data;
snd_dg00x_stream_lock_release(dg00x);
return 0;
}
static int pcm_hw_params(struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *hw_params)
{
struct snd_dg00x *dg00x = substream->private_data;
int err;
err = snd_pcm_lib_alloc_vmalloc_buffer(substream,
params_buffer_bytes(hw_params));
if (err < 0)
return err;
if (substream->runtime->status->state == SNDRV_PCM_STATE_OPEN) {
unsigned int rate = params_rate(hw_params);
unsigned int frames_per_period = params_period_size(hw_params);
mutex_lock(&dg00x->mutex);
err = snd_dg00x_stream_reserve_duplex(dg00x, rate,
frames_per_period);
if (err >= 0)
++dg00x->substreams_counter;
mutex_unlock(&dg00x->mutex);
}
return err;
}
static int pcm_hw_free(struct snd_pcm_substream *substream)
{
struct snd_dg00x *dg00x = substream->private_data;
mutex_lock(&dg00x->mutex);
if (substream->runtime->status->state != SNDRV_PCM_STATE_OPEN)
--dg00x->substreams_counter;
snd_dg00x_stream_stop_duplex(dg00x);
mutex_unlock(&dg00x->mutex);
return snd_pcm_lib_free_vmalloc_buffer(substream);
}
static int pcm_capture_prepare(struct snd_pcm_substream *substream)
{
struct snd_dg00x *dg00x = substream->private_data;
int err;
mutex_lock(&dg00x->mutex);
err = snd_dg00x_stream_start_duplex(dg00x);
if (err >= 0)
amdtp_stream_pcm_prepare(&dg00x->tx_stream);
mutex_unlock(&dg00x->mutex);
return err;
}
static int pcm_playback_prepare(struct snd_pcm_substream *substream)
{
struct snd_dg00x *dg00x = substream->private_data;
int err;
mutex_lock(&dg00x->mutex);
err = snd_dg00x_stream_start_duplex(dg00x);
if (err >= 0) {
amdtp_stream_pcm_prepare(&dg00x->rx_stream);
amdtp_dot_reset(&dg00x->rx_stream);
}
mutex_unlock(&dg00x->mutex);
return err;
}
static int pcm_capture_trigger(struct snd_pcm_substream *substream, int cmd)
{
struct snd_dg00x *dg00x = substream->private_data;
switch (cmd) {
case SNDRV_PCM_TRIGGER_START:
amdtp_stream_pcm_trigger(&dg00x->tx_stream, substream);
break;
case SNDRV_PCM_TRIGGER_STOP:
amdtp_stream_pcm_trigger(&dg00x->tx_stream, NULL);
break;
default:
return -EINVAL;
}
return 0;
}
static int pcm_playback_trigger(struct snd_pcm_substream *substream, int cmd)
{
struct snd_dg00x *dg00x = substream->private_data;
switch (cmd) {
case SNDRV_PCM_TRIGGER_START:
amdtp_stream_pcm_trigger(&dg00x->rx_stream, substream);
break;
case SNDRV_PCM_TRIGGER_STOP:
amdtp_stream_pcm_trigger(&dg00x->rx_stream, NULL);
break;
default:
return -EINVAL;
}
return 0;
}
static snd_pcm_uframes_t pcm_capture_pointer(struct snd_pcm_substream *sbstrm)
{
struct snd_dg00x *dg00x = sbstrm->private_data;
return amdtp_stream_pcm_pointer(&dg00x->tx_stream);
}
static snd_pcm_uframes_t pcm_playback_pointer(struct snd_pcm_substream *sbstrm)
{
struct snd_dg00x *dg00x = sbstrm->private_data;
return amdtp_stream_pcm_pointer(&dg00x->rx_stream);
}
static int pcm_capture_ack(struct snd_pcm_substream *substream)
{
struct snd_dg00x *dg00x = substream->private_data;
return amdtp_stream_pcm_ack(&dg00x->tx_stream);
}
static int pcm_playback_ack(struct snd_pcm_substream *substream)
{
struct snd_dg00x *dg00x = substream->private_data;
return amdtp_stream_pcm_ack(&dg00x->rx_stream);
}
int snd_dg00x_create_pcm_devices(struct snd_dg00x *dg00x)
{
static const struct snd_pcm_ops capture_ops = {
.open = pcm_open,
.close = pcm_close,
.ioctl = snd_pcm_lib_ioctl,
.hw_params = pcm_hw_params,
.hw_free = pcm_hw_free,
.prepare = pcm_capture_prepare,
.trigger = pcm_capture_trigger,
.pointer = pcm_capture_pointer,
.ack = pcm_capture_ack,
.page = snd_pcm_lib_get_vmalloc_page,
};
static const struct snd_pcm_ops playback_ops = {
.open = pcm_open,
.close = pcm_close,
.ioctl = snd_pcm_lib_ioctl,
.hw_params = pcm_hw_params,
.hw_free = pcm_hw_free,
.prepare = pcm_playback_prepare,
.trigger = pcm_playback_trigger,
.pointer = pcm_playback_pointer,
.ack = pcm_playback_ack,
.page = snd_pcm_lib_get_vmalloc_page,
};
struct snd_pcm *pcm;
int err;
err = snd_pcm_new(dg00x->card, dg00x->card->driver, 0, 1, 1, &pcm);
if (err < 0)
return err;
pcm->private_data = dg00x;
snprintf(pcm->name, sizeof(pcm->name),
"%s PCM", dg00x->card->shortname);
snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &playback_ops);
snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &capture_ops);
return 0;
}