C++ snd_pcm_lib_buffer_bytes函数代码示例

static snd_pcm_uframes_t
dma_pointer(struct snd_pcm_substream *substream)
{
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct runtime_data *prtd = runtime->private_data;
	unsigned long res;

	pr_debug("Entered %s\n", __func__);

	res = prtd->dma_pos - prtd->dma_start;

	pr_debug("Pointer offset: %lu\n", res);

	/* we seem to be getting the odd error from the pcm library due
	 * to out-of-bounds pointers. this is maybe due to the dma engine
	 * not having loaded the new values for the channel before being
	 * called... (todo - fix )
	 */

	if (res >= snd_pcm_lib_buffer_bytes(substream)) {
		if (res == snd_pcm_lib_buffer_bytes(substream))
			res = 0;
	}

	return bytes_to_frames(substream->runtime, res);
}

static snd_pcm_uframes_t
dma_pointer(struct snd_pcm_substream *substream)
{
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct runtime_data *prtd = runtime->private_data;
	unsigned long res;

	pr_debug("Entered %s\n", __func__);

	res = prtd->dma_pos - prtd->dma_start;

	pr_debug("Pointer offset: %lu\n", res);

	/*                                                             
                                                                  
                                                                 
                           
  */

	if (res >= snd_pcm_lib_buffer_bytes(substream)) {
		if (res == snd_pcm_lib_buffer_bytes(substream))
			res = 0;
	}

	return bytes_to_frames(substream->runtime, res);
}

static snd_pcm_uframes_t
	s3c_idma_pointer(struct snd_pcm_substream *substream)
{
	struct snd_soc_pcm_runtime *rtd = substream->private_data;
	struct s3c_dma_params *dma = rtd->dai->cpu_dai->dma_data;
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct lpam_i2s_pdata *prtd = runtime->private_data;
	dma_addr_t src, dst;
	unsigned long res;

	spin_lock(&prtd->lock);
#if 1
	dst = dma->dma_addr;
	s3c_idma_getpos(&src);
	res = src - runtime->dma_addr;
#else
	res = prtd->pos - prtd->start;
#endif
	spin_unlock(&prtd->lock);


	/* By Jung */
	if (res >= snd_pcm_lib_buffer_bytes(substream)) {
		if (res == snd_pcm_lib_buffer_bytes(substream))
			res = 0;
	}

	return bytes_to_frames(substream->runtime, res);
}

/* prepare callback */
static int snd_bcm2835_pcm_prepare(struct snd_pcm_substream *substream)
{
	struct bcm2835_chip *chip = snd_pcm_substream_chip(substream);
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct bcm2835_alsa_stream *alsa_stream = runtime->private_data;
	int channels;
	int err;

	audio_info(" .. IN\n");

	if (mutex_lock_interruptible(&chip->audio_mutex))
		return -EINTR;

	/* notify the vchiq that it should enter spdif passthrough mode by
	 * setting channels=0 (see
	 * https://github.com/raspberrypi/linux/issues/528) */
	if (chip->spdif_status & IEC958_AES0_NONAUDIO)
		channels = 0;
	else
		channels = alsa_stream->channels;

	err = bcm2835_audio_set_params(alsa_stream, channels,
		alsa_stream->params_rate,
		alsa_stream->pcm_format_width);
	if (err < 0) {
		audio_error(" error setting hw params\n");
	}

	bcm2835_audio_setup(alsa_stream);

	/* in preparation of the stream, set the controls (volume level) of the stream */
	bcm2835_audio_set_ctls(alsa_stream->chip);


	memset(&alsa_stream->pcm_indirect, 0, sizeof(alsa_stream->pcm_indirect));

	alsa_stream->pcm_indirect.hw_buffer_size =
		alsa_stream->pcm_indirect.sw_buffer_size =
		snd_pcm_lib_buffer_bytes(substream);

	alsa_stream->buffer_size = snd_pcm_lib_buffer_bytes(substream);
	alsa_stream->period_size = snd_pcm_lib_period_bytes(substream);
	alsa_stream->pos = 0;

	audio_debug("buffer_size=%d, period_size=%d pos=%d frame_bits=%d\n",
		alsa_stream->buffer_size, alsa_stream->period_size,
		alsa_stream->pos, runtime->frame_bits);

	mutex_unlock(&chip->audio_mutex);
	audio_info(" .. OUT\n");
	return 0;
}

static snd_pcm_uframes_t 
	s3c24xx_pcm_pointer(struct snd_pcm_substream *substream)
{
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct s3c24xx_runtime_data *prtd = runtime->private_data;
	unsigned long res;

	s3cdbg("Entered %s\n", __FUNCTION__);

	spin_lock(&prtd->lock);

#if defined (CONFIG_CPU_S3C6400) || defined (CONFIG_CPU_S3C6410)
	if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)  
		res = prtd->dma_pos - prtd->dma_start;
	else 
		res = prtd->dma_pos - prtd->dma_start;	
#else
	if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
		res = dst - prtd->dma_start;
	else
		res = src - prtd->dma_start;
#endif

	spin_unlock(&prtd->lock);

	/* we seem to be getting the odd error from the pcm library due
	 * to out-of-bounds pointers. this is maybe due to the dma engine
	 * not having loaded the new values for the channel before being
	 * callled... (todo - fix )
	 */
	
	/* Playback mode */	
	if(substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {	
		if (res >= (snd_pcm_lib_buffer_bytes(substream) * ANDROID_BUF_NUM)) {
			if (res == (snd_pcm_lib_buffer_bytes(substream) * ANDROID_BUF_NUM))
				res = 0;
		}
	}

	/* Capture mode */	
	else {	
		if (res >= (snd_pcm_lib_buffer_bytes(substream))) {
			if (res == (snd_pcm_lib_buffer_bytes(substream)))
				res = 0;
		}
	}

	return bytes_to_frames(substream->runtime, res);
}

static snd_pcm_uframes_t sun7i_pcm_pointer(struct snd_pcm_substream *substream)
{
	unsigned long play_res = 0, capture_res = 0;
	struct sun7i_playback_runtime_data *play_prtd = NULL;
	struct sun7i_capture_runtime_data *capture_prtd = NULL;
	snd_pcm_uframes_t play_offset = 0;
	struct snd_pcm_runtime *play_runtime = NULL;
	struct snd_pcm_runtime *capture_runtime = NULL;
	
    if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
		play_prtd = substream->runtime->private_data;
		play_runtime = substream->runtime;
		spin_lock(&play_prtd->lock);
		sw_dma_getposition(play_prtd->dma_hdl, (dma_addr_t*)&play_dmasrc, (dma_addr_t*)&play_dmadst);
		play_res = play_dmasrc + play_prtd->dma_period - play_prtd->dma_start;
		play_offset = bytes_to_frames(play_runtime, play_res);
		
		spin_unlock(&play_prtd->lock);
		if (play_offset >= substream->runtime->buffer_size) {
			play_offset = 0;
		}
		return play_offset;
    } else {
    	/*pr_info("CAPTUR:sun7i_i2sdma.c::func:%s(line:%d)\n",__func__,__LINE__);*/
		capture_prtd = substream->runtime->private_data;
		spin_lock(&capture_prtd->lock);
		sw_dma_getposition(capture_prtd->dma_hdl, (dma_addr_t*)&capture_dmasrc, (dma_addr_t*)&capture_dmadst);
		capture_res = capture_dmadst + capture_prtd->dma_period - capture_prtd->dma_start;
		spin_unlock(&capture_prtd->lock);
#if 1
		{
			snd_pcm_uframes_t capture_offset = 0;

			capture_runtime = substream->runtime;
			capture_offset = bytes_to_frames(capture_runtime, capture_res);
			if (capture_offset >= substream->runtime->buffer_size) {
				capture_offset = 0;
			}
			return capture_offset;
		}
#else
		if (capture_res >= snd_pcm_lib_buffer_bytes(substream)) {
			if (capture_res == snd_pcm_lib_buffer_bytes(substream))
				capture_res = 0;
		}
		return bytes_to_frames(substream->runtime, capture_res);
#endif
    }
}

static int msm_compr_playback_prepare(struct snd_pcm_substream *substream)
{
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct compr_audio *compr = runtime->private_data;
	struct msm_audio *prtd = &compr->prtd;
	int ret;

	pr_debug("%s\n", __func__);
	prtd->pcm_size = snd_pcm_lib_buffer_bytes(substream);
	prtd->pcm_count = snd_pcm_lib_period_bytes(substream);
	prtd->pcm_irq_pos = 0;
	/* rate and channels are sent to audio driver */
	prtd->samp_rate = runtime->rate;
	prtd->channel_mode = runtime->channels;
	prtd->out_head = 0;
	if (prtd->enabled)
		return 0;

	ret = q6asm_media_format_block(prtd->audio_client, compr->codec);
	if (ret < 0)
		pr_info("%s: CMD Format block failed\n", __func__);

	atomic_set(&prtd->out_count, runtime->periods);

	prtd->enabled = 1;
	prtd->cmd_ack = 0;

	return 0;
}

static int cygnus_pcm_prepare(struct snd_pcm_substream *substream)
{
	struct snd_soc_pcm_runtime *rtd = substream->private_data;
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct cygnus_aio_port *aio;
	unsigned long bufsize, periodsize;
	int ret = 0;
	bool is_play;
	u32 start;
	struct ringbuf_regs *p_rbuf = NULL;

	aio = cygnus_dai_get_dma_data(substream);
	dev_dbg(rtd->cpu_dai->dev, "%s port %d\n", __func__, aio->portnum);

	bufsize = snd_pcm_lib_buffer_bytes(substream);
	periodsize = snd_pcm_lib_period_bytes(substream);

	dev_dbg(rtd->cpu_dai->dev, "%s (buf_size %lu) (period_size %lu)\n",
			__func__, bufsize, periodsize);

	configure_ringbuf_regs(substream);

	p_rbuf = get_ringbuf(substream);

	start = runtime->dma_addr;

	is_play = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) ? 1 : 0;

	ringbuf_set_initial(aio->cygaud->audio, p_rbuf, is_play, start,
				periodsize, bufsize);

	return ret;
}

static void dmaengine_pcm_dma_complete(void *arg)
{
	struct snd_pcm_substream *substream = arg;
	struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);

#ifdef CONFIG_ARCH_ROCKCHIP
	if(debug_audio_timeout){
		struct snd_pcm_runtime *runtime = substream->runtime;
		static ktime_t before = {0},after = {0};
		s64 t;
		before = after;
		after = ktime_get();
		t = ktime_to_us(ktime_sub(after, before));

		if(t > (snd_pcm_lib_period_bytes(substream)/4+32)*1000*1000/runtime->rate
			&& t != ktime_to_us(after)) // (23220)4096/4/44100 + 32/44100
		{
				printk(KERN_DEBUG "Time out:: Audio DMA buffdone time out!!! the time = %lld!\n", t);
		}
		//printk(KERN_DEBUG "audio DMA callback time = %lld\n", t);
	}
#endif
	prtd->pos += snd_pcm_lib_period_bytes(substream);
	if (prtd->pos >= snd_pcm_lib_buffer_bytes(substream))
		prtd->pos = 0;

	snd_pcm_period_elapsed(substream);
}

static int dmaengine_pcm_prepare_and_submit(struct snd_pcm_substream *substream)
{
	struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
	struct dma_chan *chan = prtd->dma_chan;
	struct dma_async_tx_descriptor *desc;
	enum dma_transfer_direction direction;
	unsigned long flags = DMA_CTRL_ACK;

	direction = snd_pcm_substream_to_dma_direction(substream);

	if (!substream->runtime->no_period_wakeup)
		flags |= DMA_PREP_INTERRUPT;

	prtd->pos = 0;
	desc = dmaengine_prep_dma_cyclic(chan,
		substream->runtime->dma_addr,
		snd_pcm_lib_buffer_bytes(substream),
		snd_pcm_lib_period_bytes(substream), direction, flags);

	if (!desc)
		return -ENOMEM;

	desc->callback = dmaengine_pcm_dma_complete;
	desc->callback_param = substream;
	prtd->cookie = dmaengine_submit(desc);

	return 0;
}

void rsnd_dma_start(struct rsnd_dma *dma)
{
	struct rsnd_mod *mod = rsnd_dma_to_mod(dma);
	struct rsnd_priv *priv = rsnd_mod_to_priv(mod);
	struct rsnd_dai_stream *io = rsnd_mod_to_io(mod);
	struct snd_pcm_substream *substream = io->substream;
	struct device *dev = rsnd_priv_to_dev(priv);
	struct dma_async_tx_descriptor *desc;

	desc = dmaengine_prep_dma_cyclic(dma->chan,
					 (dma->addr) ? dma->addr :
					 substream->runtime->dma_addr,
					 snd_pcm_lib_buffer_bytes(substream),
					 snd_pcm_lib_period_bytes(substream),
					 dma->dir,
					 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);

	if (!desc) {
		dev_err(dev, "dmaengine_prep_slave_sg() fail\n");
		return;
	}

	desc->callback		= rsnd_dma_complete;
	desc->callback_param	= dma;

	if (dmaengine_submit(desc) < 0) {
		dev_err(dev, "dmaengine_submit() fail\n");
		return;
	}

	dma_async_issue_pending(dma->chan);
}

static inline int sst_calc_tstamp(struct intel_sst_drv *ctx,
		struct pcm_stream_info *info,
		struct snd_pcm_substream *substream,
		struct snd_sst_tstamp *fw_tstamp)
{
	size_t delay_bytes, delay_frames;
	size_t buffer_sz;
	u32 pointer_bytes, pointer_samples;

	dev_dbg(ctx->dev, "mrfld ring_buffer_counter %llu in bytes\n",
			fw_tstamp->ring_buffer_counter);
	dev_dbg(ctx->dev, "mrfld hardware_counter %llu in bytes\n",
			 fw_tstamp->hardware_counter);
	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
		delay_bytes = (size_t) (fw_tstamp->ring_buffer_counter -
					fw_tstamp->hardware_counter);
	else
		delay_bytes = (size_t) (fw_tstamp->hardware_counter -
					fw_tstamp->ring_buffer_counter);
	delay_frames = bytes_to_frames(substream->runtime, delay_bytes);
	buffer_sz = snd_pcm_lib_buffer_bytes(substream);
	div_u64_rem(fw_tstamp->ring_buffer_counter, buffer_sz, &pointer_bytes);
	pointer_samples = bytes_to_samples(substream->runtime, pointer_bytes);

	dev_dbg(ctx->dev, "pcm delay %zu in bytes\n", delay_bytes);

	info->buffer_ptr = pointer_samples / substream->runtime->channels;

	info->pcm_delay = delay_frames / substream->runtime->channels;
	dev_dbg(ctx->dev, "buffer ptr %llu pcm_delay rep: %llu\n",
			info->buffer_ptr, info->pcm_delay);
	return 0;
}

static int snd_ad1816a_playback_prepare(snd_pcm_substream_t *substream)
{
	ad1816a_t *chip = snd_pcm_substream_chip(substream);
	unsigned long flags;
	snd_pcm_runtime_t *runtime = substream->runtime;
	unsigned int size;

	spin_lock_irqsave(&chip->lock, flags);

	chip->p_dma_size = size = snd_pcm_lib_buffer_bytes(substream);
	snd_ad1816a_out_mask(chip, AD1816A_PLAYBACK_CONFIG,
		AD1816A_PLAYBACK_ENABLE | AD1816A_PLAYBACK_PIO, 0x00);

	snd_dma_program(chip->dma1, runtime->dma_addr, size,
			DMA_MODE_WRITE | DMA_AUTOINIT);

	snd_ad1816a_write(chip, AD1816A_PLAYBACK_SAMPLE_RATE, runtime->rate);
	snd_ad1816a_out_mask(chip, AD1816A_PLAYBACK_CONFIG,
		AD1816A_FMT_ALL | AD1816A_FMT_STEREO,
		snd_ad1816a_get_format(chip, runtime->format,
			runtime->channels));

	snd_ad1816a_write(chip, AD1816A_PLAYBACK_BASE_COUNT,
		snd_pcm_lib_period_bytes(substream) / 4 - 1);

	spin_unlock_irqrestore(&chip->lock, flags);
	return 0;
}

static int snd_als300_capture_prepare(struct snd_pcm_substream *substream)
{
	u32 tmp;
	struct snd_als300 *chip = snd_pcm_substream_chip(substream);
	struct snd_pcm_runtime *runtime = substream->runtime;
	unsigned short period_bytes = snd_pcm_lib_period_bytes(substream);
	unsigned short buffer_bytes = snd_pcm_lib_buffer_bytes(substream);

	spin_lock_irq(&chip->reg_lock);
	tmp = snd_als300_gcr_read(chip->port, RECORD_CONTROL);
	tmp &= ~TRANSFER_START;

	snd_als300_dbgplay("Period bytes: %d Buffer bytes %d\n", period_bytes,
							buffer_bytes);

	/* set block size */
	tmp &= 0xffff0000;
	tmp |= period_bytes - 1;

	/* set dma area */
	snd_als300_gcr_write(chip->port, RECORD_CONTROL, tmp);
	snd_als300_gcr_write(chip->port, RECORD_START,
					runtime->dma_addr);
	snd_als300_gcr_write(chip->port, RECORD_END,
					runtime->dma_addr + buffer_bytes - 1);
	spin_unlock_irq(&chip->reg_lock);
	return 0;
}

static int snd_ad1816a_capture_prepare(struct snd_pcm_substream *substream)
{
	struct snd_ad1816a *chip = snd_pcm_substream_chip(substream);
	unsigned long flags;
	struct snd_pcm_runtime *runtime = substream->runtime;
	unsigned int size, rate;

	spin_lock_irqsave(&chip->lock, flags);

	chip->c_dma_size = size = snd_pcm_lib_buffer_bytes(substream);
	snd_ad1816a_out_mask(chip, AD1816A_CAPTURE_CONFIG,
		AD1816A_CAPTURE_ENABLE | AD1816A_CAPTURE_PIO, 0x00);

	snd_dma_program(chip->dma2, runtime->dma_addr, size,
			DMA_MODE_READ | DMA_AUTOINIT);

	rate = runtime->rate;
	if (chip->clock_freq)
		rate = (rate * 33000) / chip->clock_freq;
	snd_ad1816a_write(chip, AD1816A_CAPTURE_SAMPLE_RATE, rate);
	snd_ad1816a_out_mask(chip, AD1816A_CAPTURE_CONFIG,
		AD1816A_FMT_ALL | AD1816A_FMT_STEREO,
		snd_ad1816a_get_format(chip, runtime->format,
			runtime->channels));

	snd_ad1816a_write(chip, AD1816A_CAPTURE_BASE_COUNT,
		snd_pcm_lib_period_bytes(substream) / 4 - 1);

	spin_unlock_irqrestore(&chip->lock, flags);
	return 0;
}