Orange Pi5 kernel

/*
 * 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; \
}
 
#define dw_pcm_rx_fn(sample_bits) \
static unsigned int dw_pcm_rx_##sample_bits(struct dw_i2s_dev *dev, \
<------><------>struct snd_pcm_runtime *runtime, unsigned int rx_ptr, \
<------><------>bool *period_elapsed) \
{ \
<------>u##sample_bits (*p)[2] = (void *)runtime->dma_area; \
<------>unsigned int period_pos = rx_ptr % runtime->period_size; \
<------>int i; \
\
<------>for (i = 0; i < dev->fifo_th; i++) { \
<------><------>p[rx_ptr][0] = ioread32(dev->i2s_base + LRBR_LTHR(0)); \
<------><------>p[rx_ptr][1] = ioread32(dev->i2s_base + RRBR_RTHR(0)); \
<------><------>period_pos++; \
<------><------>if (++rx_ptr >= runtime->buffer_size) \
<------><------><------>rx_ptr = 0; \
<------>} \
<------>*period_elapsed = period_pos >= runtime->period_size; \
<------>return rx_ptr; \
}
 
dw_pcm_tx_fn(16);
dw_pcm_tx_fn(32);
dw_pcm_rx_fn(16);
dw_pcm_rx_fn(32);
 
#undef dw_pcm_tx_fn
#undef dw_pcm_rx_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_S24_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,
};
 
static void dw_pcm_transfer(struct dw_i2s_dev *dev, bool push)
{
<------>struct snd_pcm_substream *substream;
<------>bool active, period_elapsed;
 
<------>rcu_read_lock();
<------>if (push)
<------><------>substream = rcu_dereference(dev->tx_substream);
<------>else
<------><------>substream = rcu_dereference(dev->rx_substream);
<------>active = substream && snd_pcm_running(substream);
<------>if (active) {
<------><------>unsigned int ptr;
<------><------>unsigned int new_ptr;
 
<------><------>if (push) {
<------><------><------>ptr = READ_ONCE(dev->tx_ptr);
<------><------><------>new_ptr = dev->tx_fn(dev, substream->runtime, ptr,
<------><------><------><------><------>&period_elapsed);
<------><------><------>cmpxchg(&dev->tx_ptr, ptr, new_ptr);
<------><------>} else {
<------><------><------>ptr = READ_ONCE(dev->rx_ptr);
<------><------><------>new_ptr = dev->rx_fn(dev, substream->runtime, ptr,
<------><------><------><------><------>&period_elapsed);
<------><------><------>cmpxchg(&dev->rx_ptr, ptr, new_ptr);
<------><------>}
 
<------><------>if (period_elapsed)
<------><------><------>snd_pcm_period_elapsed(substream);
<------>}
<------>rcu_read_unlock();
}
 
void dw_pcm_push_tx(struct dw_i2s_dev *dev)
{
<------>dw_pcm_transfer(dev, true);
}
 
void dw_pcm_pop_rx(struct dw_i2s_dev *dev)
{
<------>dw_pcm_transfer(dev, false);
}
 
static int dw_pcm_open(struct snd_soc_component *component,
<------><------>       struct snd_pcm_substream *substream)
{
<------>struct snd_pcm_runtime *runtime = substream->runtime;
<------>struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
<------>struct dw_i2s_dev *dev = snd_soc_dai_get_drvdata(asoc_rtd_to_cpu(rtd, 0));
 
<------>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_soc_component *component,
<------><------><------>struct snd_pcm_substream *substream)
{
<------>synchronize_rcu();
<------>return 0;
}
 
static int dw_pcm_hw_params(struct snd_soc_component *component,
<------><------><------>    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;
 
<------>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;
<------><------>dev->rx_fn = dw_pcm_rx_16;
<------><------>break;
<------>case SNDRV_PCM_FORMAT_S24_LE:
<------>case SNDRV_PCM_FORMAT_S32_LE:
<------><------>dev->tx_fn = dw_pcm_tx_32;
<------><------>dev->rx_fn = dw_pcm_rx_32;
<------><------>break;
<------>default:
<------><------>dev_err(dev->dev, "invalid format\n");
<------><------>return -EINVAL;
<------>}
 
<------>return 0;
}
 
static int dw_pcm_trigger(struct snd_soc_component *component,
<------><------><------>  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:
<------><------>if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
<------><------><------>WRITE_ONCE(dev->tx_ptr, 0);
<------><------><------>rcu_assign_pointer(dev->tx_substream, substream);
<------><------>} else {
<------><------><------>WRITE_ONCE(dev->rx_ptr, 0);
<------><------><------>rcu_assign_pointer(dev->rx_substream, substream);
<------><------>}
<------><------>break;
<------>case SNDRV_PCM_TRIGGER_STOP:
<------>case SNDRV_PCM_TRIGGER_SUSPEND:
<------>case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
<------><------>if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
<------><------><------>rcu_assign_pointer(dev->tx_substream, NULL);
<------><------>else
<------><------><------>rcu_assign_pointer(dev->rx_substream, NULL);
<------><------>break;
<------>default:
<------><------>ret = -EINVAL;
<------><------>break;
<------>}
 
<------>return ret;
}
 
static snd_pcm_uframes_t dw_pcm_pointer(struct snd_soc_component *component,
<------><------><------><------><------>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;
 
<------>if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
<------><------>pos = READ_ONCE(dev->tx_ptr);
<------>else
<------><------>pos = READ_ONCE(dev->rx_ptr);
 
<------>return pos < runtime->buffer_size ? pos : 0;
}
 
static int dw_pcm_new(struct snd_soc_component *component,
<------><------>      struct snd_soc_pcm_runtime *rtd)
{
<------>size_t size = dw_pcm_hardware.buffer_bytes_max;
 
<------>snd_pcm_set_managed_buffer_all(rtd->pcm,
<------><------><------>SNDRV_DMA_TYPE_CONTINUOUS,
<------><------><------>NULL, size, size);
<------>return 0;
}
 
static const struct snd_soc_component_driver dw_pcm_component = {
<------>.open		= dw_pcm_open,
<------>.close		= dw_pcm_close,
<------>.hw_params	= dw_pcm_hw_params,
<------>.trigger	= dw_pcm_trigger,
<------>.pointer	= dw_pcm_pointer,
<------>.pcm_construct	= dw_pcm_new,
};
 
int dw_pcm_register(struct platform_device *pdev)
{
<------>return devm_snd_soc_register_component(&pdev->dev, &dw_pcm_component,
<------><------><------><------><------>       NULL, 0);
}