linux/sound/soc/dwc/designware_pcm.c

226 lines
5.6 KiB
C

/*
* ALSA SoC Synopsys PIO PCM for I2S driver
*
* sound/soc/dwc/designware_pcm.c
*
* Copyright (C) 2016 Synopsys
* Jose Abreu <joabreu@synopsys.com>
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
* warranty of any kind, whether express or implied.
*/
#include <linux/io.h>
#include <linux/rcupdate.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include "local.h"
#define BUFFER_BYTES_MAX (3 * 2 * 8 * PERIOD_BYTES_MIN)
#define PERIOD_BYTES_MIN 4096
#define PERIODS_MIN 2
#define dw_pcm_tx_fn(sample_bits) \
static unsigned int dw_pcm_tx_##sample_bits(struct dw_i2s_dev *dev, \
struct snd_pcm_runtime *runtime, unsigned int tx_ptr, \
bool *period_elapsed) \
{ \
const u##sample_bits (*p)[2] = (void *)runtime->dma_area; \
unsigned int period_pos = tx_ptr % runtime->period_size; \
int i; \
\
for (i = 0; i < dev->fifo_th; i++) { \
iowrite32(p[tx_ptr][0], dev->i2s_base + LRBR_LTHR(0)); \
iowrite32(p[tx_ptr][1], dev->i2s_base + RRBR_RTHR(0)); \
period_pos++; \
if (++tx_ptr >= runtime->buffer_size) \
tx_ptr = 0; \
} \
*period_elapsed = period_pos >= runtime->period_size; \
return tx_ptr; \
}
dw_pcm_tx_fn(16);
dw_pcm_tx_fn(32);
#undef dw_pcm_tx_fn
static const struct snd_pcm_hardware dw_pcm_hardware = {
.info = SNDRV_PCM_INFO_INTERLEAVED |
SNDRV_PCM_INFO_MMAP |
SNDRV_PCM_INFO_MMAP_VALID |
SNDRV_PCM_INFO_BLOCK_TRANSFER,
.rates = SNDRV_PCM_RATE_32000 |
SNDRV_PCM_RATE_44100 |
SNDRV_PCM_RATE_48000,
.rate_min = 32000,
.rate_max = 48000,
.formats = SNDRV_PCM_FMTBIT_S16_LE |
SNDRV_PCM_FMTBIT_S32_LE,
.channels_min = 2,
.channels_max = 2,
.buffer_bytes_max = BUFFER_BYTES_MAX,
.period_bytes_min = PERIOD_BYTES_MIN,
.period_bytes_max = BUFFER_BYTES_MAX / PERIODS_MIN,
.periods_min = PERIODS_MIN,
.periods_max = BUFFER_BYTES_MAX / PERIOD_BYTES_MIN,
.fifo_size = 16,
};
void dw_pcm_push_tx(struct dw_i2s_dev *dev)
{
struct snd_pcm_substream *tx_substream;
bool tx_active, period_elapsed;
rcu_read_lock();
tx_substream = rcu_dereference(dev->tx_substream);
tx_active = tx_substream && snd_pcm_running(tx_substream);
if (tx_active) {
unsigned int tx_ptr = READ_ONCE(dev->tx_ptr);
unsigned int new_tx_ptr = dev->tx_fn(dev, tx_substream->runtime,
tx_ptr, &period_elapsed);
cmpxchg(&dev->tx_ptr, tx_ptr, new_tx_ptr);
if (period_elapsed)
snd_pcm_period_elapsed(tx_substream);
}
rcu_read_unlock();
}
EXPORT_SYMBOL_GPL(dw_pcm_push_tx);
static int dw_pcm_open(struct snd_pcm_substream *substream)
{
struct snd_pcm_runtime *runtime = substream->runtime;
struct snd_soc_pcm_runtime *rtd = substream->private_data;
struct dw_i2s_dev *dev = snd_soc_dai_get_drvdata(rtd->cpu_dai);
snd_soc_set_runtime_hwparams(substream, &dw_pcm_hardware);
snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
runtime->private_data = dev;
return 0;
}
static int dw_pcm_close(struct snd_pcm_substream *substream)
{
synchronize_rcu();
return 0;
}
static int dw_pcm_hw_params(struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *hw_params)
{
struct snd_pcm_runtime *runtime = substream->runtime;
struct dw_i2s_dev *dev = runtime->private_data;
int ret;
switch (params_channels(hw_params)) {
case 2:
break;
default:
dev_err(dev->dev, "invalid channels number\n");
return -EINVAL;
}
switch (params_format(hw_params)) {
case SNDRV_PCM_FORMAT_S16_LE:
dev->tx_fn = dw_pcm_tx_16;
break;
case SNDRV_PCM_FORMAT_S32_LE:
dev->tx_fn = dw_pcm_tx_32;
break;
default:
dev_err(dev->dev, "invalid format\n");
return -EINVAL;
}
if (substream->stream != SNDRV_PCM_STREAM_PLAYBACK) {
dev_err(dev->dev, "only playback is available\n");
return -EINVAL;
}
ret = snd_pcm_lib_malloc_pages(substream,
params_buffer_bytes(hw_params));
if (ret < 0)
return ret;
else
return 0;
}
static int dw_pcm_hw_free(struct snd_pcm_substream *substream)
{
return snd_pcm_lib_free_pages(substream);
}
static int dw_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
{
struct snd_pcm_runtime *runtime = substream->runtime;
struct dw_i2s_dev *dev = runtime->private_data;
int ret = 0;
switch (cmd) {
case SNDRV_PCM_TRIGGER_START:
case SNDRV_PCM_TRIGGER_RESUME:
case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
WRITE_ONCE(dev->tx_ptr, 0);
rcu_assign_pointer(dev->tx_substream, substream);
break;
case SNDRV_PCM_TRIGGER_STOP:
case SNDRV_PCM_TRIGGER_SUSPEND:
case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
rcu_assign_pointer(dev->tx_substream, NULL);
break;
default:
ret = -EINVAL;
break;
}
return ret;
}
static snd_pcm_uframes_t dw_pcm_pointer(struct snd_pcm_substream *substream)
{
struct snd_pcm_runtime *runtime = substream->runtime;
struct dw_i2s_dev *dev = runtime->private_data;
snd_pcm_uframes_t pos = READ_ONCE(dev->tx_ptr);
return pos < runtime->buffer_size ? pos : 0;
}
static int dw_pcm_new(struct snd_soc_pcm_runtime *rtd)
{
size_t size = dw_pcm_hardware.buffer_bytes_max;
return snd_pcm_lib_preallocate_pages_for_all(rtd->pcm,
SNDRV_DMA_TYPE_CONTINUOUS,
snd_dma_continuous_data(GFP_KERNEL), size, size);
}
static void dw_pcm_free(struct snd_pcm *pcm)
{
snd_pcm_lib_preallocate_free_for_all(pcm);
}
static const struct snd_pcm_ops dw_pcm_ops = {
.open = dw_pcm_open,
.close = dw_pcm_close,
.ioctl = snd_pcm_lib_ioctl,
.hw_params = dw_pcm_hw_params,
.hw_free = dw_pcm_hw_free,
.trigger = dw_pcm_trigger,
.pointer = dw_pcm_pointer,
};
static const struct snd_soc_platform_driver dw_pcm_platform = {
.pcm_new = dw_pcm_new,
.pcm_free = dw_pcm_free,
.ops = &dw_pcm_ops,
};
int dw_pcm_register(struct platform_device *pdev)
{
return devm_snd_soc_register_platform(&pdev->dev, &dw_pcm_platform);
}
EXPORT_SYMBOL_GPL(dw_pcm_register);