nm256.c

LINUX 2.6.17.4的源码

	runtime->rate = samplerates[rate_index];

	switch (substream->stream) {
	case SNDRV_PCM_STREAM_PLAYBACK:
		snd_nm256_load_coefficient(chip, 0, rate_index); /* 0 = playback */
		snd_nm256_writeb(chip,
				 NM_PLAYBACK_REG_OFFSET + NM_RATE_REG_OFFSET,
				 ratebits);
		break;
	case SNDRV_PCM_STREAM_CAPTURE:
		snd_nm256_load_coefficient(chip, 1, rate_index); /* 1 = record */
		snd_nm256_writeb(chip,
				 NM_RECORD_REG_OFFSET + NM_RATE_REG_OFFSET,
				 ratebits);
		break;
	}
}

/* acquire interrupt */
static int snd_nm256_acquire_irq(struct nm256 *chip)
{
	mutex_lock(&chip->irq_mutex);
	if (chip->irq < 0) {
		if (request_irq(chip->pci->irq, chip->interrupt, SA_INTERRUPT|SA_SHIRQ,
				chip->card->driver, chip)) {
			snd_printk(KERN_ERR "unable to grab IRQ %d\n", chip->pci->irq);
			mutex_unlock(&chip->irq_mutex);
			return -EBUSY;
		}
		chip->irq = chip->pci->irq;
	}
	chip->irq_acks++;
	mutex_unlock(&chip->irq_mutex);
	return 0;
}

/* release interrupt */
static void snd_nm256_release_irq(struct nm256 *chip)
{
	mutex_lock(&chip->irq_mutex);
	if (chip->irq_acks > 0)
		chip->irq_acks--;
	if (chip->irq_acks == 0 && chip->irq >= 0) {
		free_irq(chip->irq, chip);
		chip->irq = -1;
	}
	mutex_unlock(&chip->irq_mutex);
}

/*
 * start / stop
 */

/* update the watermark (current period) */
static void snd_nm256_pcm_mark(struct nm256 *chip, struct nm256_stream *s, int reg)
{
	s->cur_period++;
	s->cur_period %= s->periods;
	snd_nm256_writel(chip, reg, s->buf + s->cur_period * s->period_size);
}

#define snd_nm256_playback_mark(chip, s) snd_nm256_pcm_mark(chip, s, NM_PBUFFER_WMARK)
#define snd_nm256_capture_mark(chip, s)  snd_nm256_pcm_mark(chip, s, NM_RBUFFER_WMARK)

static void
snd_nm256_playback_start(struct nm256 *chip, struct nm256_stream *s,
			 struct snd_pcm_substream *substream)
{
	/* program buffer pointers */
	snd_nm256_writel(chip, NM_PBUFFER_START, s->buf);
	snd_nm256_writel(chip, NM_PBUFFER_END, s->buf + s->dma_size - (1 << s->shift));
	snd_nm256_writel(chip, NM_PBUFFER_CURRP, s->buf);
	snd_nm256_playback_mark(chip, s);

	/* Enable playback engine and interrupts. */
	snd_nm256_writeb(chip, NM_PLAYBACK_ENABLE_REG,
			 NM_PLAYBACK_ENABLE_FLAG | NM_PLAYBACK_FREERUN);
	/* Enable both channels. */
	snd_nm256_writew(chip, NM_AUDIO_MUTE_REG, 0x0);
}

static void
snd_nm256_capture_start(struct nm256 *chip, struct nm256_stream *s,
			struct snd_pcm_substream *substream)
{
	/* program buffer pointers */
	snd_nm256_writel(chip, NM_RBUFFER_START, s->buf);
	snd_nm256_writel(chip, NM_RBUFFER_END, s->buf + s->dma_size);
	snd_nm256_writel(chip, NM_RBUFFER_CURRP, s->buf);
	snd_nm256_capture_mark(chip, s);

	/* Enable playback engine and interrupts. */
	snd_nm256_writeb(chip, NM_RECORD_ENABLE_REG,
			 NM_RECORD_ENABLE_FLAG | NM_RECORD_FREERUN);
}

/* Stop the play engine. */
static void
snd_nm256_playback_stop(struct nm256 *chip)
{
	/* Shut off sound from both channels. */
	snd_nm256_writew(chip, NM_AUDIO_MUTE_REG,
			 NM_AUDIO_MUTE_LEFT | NM_AUDIO_MUTE_RIGHT);
	/* Disable play engine. */
	snd_nm256_writeb(chip, NM_PLAYBACK_ENABLE_REG, 0);
}

static void
snd_nm256_capture_stop(struct nm256 *chip)
{
	/* Disable recording engine. */
	snd_nm256_writeb(chip, NM_RECORD_ENABLE_REG, 0);
}

static int
snd_nm256_playback_trigger(struct snd_pcm_substream *substream, int cmd)
{
	struct nm256 *chip = snd_pcm_substream_chip(substream);
	struct nm256_stream *s = substream->runtime->private_data;
	int err = 0;

	snd_assert(s != NULL, return -ENXIO);

	spin_lock(&chip->reg_lock);
	switch (cmd) {
	case SNDRV_PCM_TRIGGER_RESUME:
		s->suspended = 0;
		/* fallthru */
	case SNDRV_PCM_TRIGGER_START:
		if (! s->running) {
			snd_nm256_playback_start(chip, s, substream);
			s->running = 1;
		}
		break;
	case SNDRV_PCM_TRIGGER_SUSPEND:
		s->suspended = 1;
		/* fallthru */
	case SNDRV_PCM_TRIGGER_STOP:
		if (s->running) {
			snd_nm256_playback_stop(chip);
			s->running = 0;
		}
		break;
	default:
		err = -EINVAL;
		break;
	}
	spin_unlock(&chip->reg_lock);
	return err;
}

static int
snd_nm256_capture_trigger(struct snd_pcm_substream *substream, int cmd)
{
	struct nm256 *chip = snd_pcm_substream_chip(substream);
	struct nm256_stream *s = substream->runtime->private_data;
	int err = 0;

	snd_assert(s != NULL, return -ENXIO);

	spin_lock(&chip->reg_lock);
	switch (cmd) {
	case SNDRV_PCM_TRIGGER_START:
	case SNDRV_PCM_TRIGGER_RESUME:
		if (! s->running) {
			snd_nm256_capture_start(chip, s, substream);
			s->running = 1;
		}
		break;
	case SNDRV_PCM_TRIGGER_STOP:
	case SNDRV_PCM_TRIGGER_SUSPEND:
		if (s->running) {
			snd_nm256_capture_stop(chip);
			s->running = 0;
		}
		break;
	default:
		err = -EINVAL;
		break;
	}
	spin_unlock(&chip->reg_lock);
	return err;
}


/*
 * prepare playback/capture channel
 */
static int snd_nm256_pcm_prepare(struct snd_pcm_substream *substream)
{
	struct nm256 *chip = snd_pcm_substream_chip(substream);
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct nm256_stream *s = runtime->private_data;

	snd_assert(s, return -ENXIO);
	s->dma_size = frames_to_bytes(runtime, substream->runtime->buffer_size);
	s->period_size = frames_to_bytes(runtime, substream->runtime->period_size);
	s->periods = substream->runtime->periods;
	s->cur_period = 0;

	spin_lock_irq(&chip->reg_lock);
	s->running = 0;
	snd_nm256_set_format(chip, s, substream);
	spin_unlock_irq(&chip->reg_lock);

	return 0;
}


/*
 * get the current pointer
 */
static snd_pcm_uframes_t
snd_nm256_playback_pointer(struct snd_pcm_substream *substream)
{
	struct nm256 *chip = snd_pcm_substream_chip(substream);
	struct nm256_stream *s = substream->runtime->private_data;
	unsigned long curp;

	snd_assert(s, return 0);
	curp = snd_nm256_readl(chip, NM_PBUFFER_CURRP) - (unsigned long)s->buf;
	curp %= s->dma_size;
	return bytes_to_frames(substream->runtime, curp);
}

static snd_pcm_uframes_t
snd_nm256_capture_pointer(struct snd_pcm_substream *substream)
{
	struct nm256 *chip = snd_pcm_substream_chip(substream);
	struct nm256_stream *s = substream->runtime->private_data;
	unsigned long curp;

	snd_assert(s != NULL, return 0);
	curp = snd_nm256_readl(chip, NM_RBUFFER_CURRP) - (unsigned long)s->buf;
	curp %= s->dma_size;	
	return bytes_to_frames(substream->runtime, curp);
}

/* Remapped I/O space can be accessible as pointer on i386 */
/* This might be changed in the future */
#ifndef __i386__
/*
 * silence / copy for playback
 */
static int
snd_nm256_playback_silence(struct snd_pcm_substream *substream,
			   int channel, /* not used (interleaved data) */
			   snd_pcm_uframes_t pos,
			   snd_pcm_uframes_t count)
{
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct nm256_stream *s = runtime->private_data;
	count = frames_to_bytes(runtime, count);
	pos = frames_to_bytes(runtime, pos);
	memset_io(s->bufptr + pos, 0, count);
	return 0;
}

static int
snd_nm256_playback_copy(struct snd_pcm_substream *substream,
			int channel, /* not used (interleaved data) */
			snd_pcm_uframes_t pos,
			void __user *src,
			snd_pcm_uframes_t count)
{
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct nm256_stream *s = runtime->private_data;
	count = frames_to_bytes(runtime, count);
	pos = frames_to_bytes(runtime, pos);
	if (copy_from_user_toio(s->bufptr + pos, src, count))
		return -EFAULT;
	return 0;
}

/*
 * copy to user
 */
static int
snd_nm256_capture_copy(struct snd_pcm_substream *substream,
		       int channel, /* not used (interleaved data) */
		       snd_pcm_uframes_t pos,
		       void __user *dst,
		       snd_pcm_uframes_t count)
{
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct nm256_stream *s = runtime->private_data;
	count = frames_to_bytes(runtime, count);
	pos = frames_to_bytes(runtime, pos);
	if (copy_to_user_fromio(dst, s->bufptr + pos, count))
		return -EFAULT;
	return 0;
}

#endif /* !__i386__ */


/*
 * update playback/capture watermarks
 */

/* spinlock held! */
static void
snd_nm256_playback_update(struct nm256 *chip)
{
	struct nm256_stream *s;

	s = &chip->streams[SNDRV_PCM_STREAM_PLAYBACK];
	if (s->running && s->substream) {
		spin_unlock(&chip->reg_lock);
		snd_pcm_period_elapsed(s->substream);
		spin_lock(&chip->reg_lock);
		snd_nm256_playback_mark(chip, s);
	}
}

/* spinlock held! */
static void
snd_nm256_capture_update(struct nm256 *chip)
{
	struct nm256_stream *s;

	s = &chip->streams[SNDRV_PCM_STREAM_CAPTURE];
	if (s->running && s->substream) {
		spin_unlock(&chip->reg_lock);
		snd_pcm_period_elapsed(s->substream);
		spin_lock(&chip->reg_lock);
		snd_nm256_capture_mark(chip, s);
	}
}

/*
 * hardware info
 */
static struct snd_pcm_hardware snd_nm256_playback =
{
	.info =			SNDRV_PCM_INFO_MMAP_IOMEM |SNDRV_PCM_INFO_MMAP_VALID |
				SNDRV_PCM_INFO_INTERLEAVED |
				/*SNDRV_PCM_INFO_PAUSE |*/
				SNDRV_PCM_INFO_RESUME,
	.formats =		SNDRV_PCM_FMTBIT_U8 | SNDRV_PCM_FMTBIT_S16_LE,
	.rates =		SNDRV_PCM_RATE_KNOT/*24k*/ | SNDRV_PCM_RATE_8000_48000,
	.rate_min =		8000,
	.rate_max =		48000,
	.channels_min =		1,
	.channels_max =		2,
	.periods_min =		2,
	.periods_max =		1024,
	.buffer_bytes_max =	128 * 1024,
	.period_bytes_min =	256,
	.period_bytes_max =	128 * 1024,
};

static struct snd_pcm_hardware snd_nm256_capture =
{
	.info =			SNDRV_PCM_INFO_MMAP_IOMEM | SNDRV_PCM_INFO_MMAP_VALID |
				SNDRV_PCM_INFO_INTERLEAVED |
				/*SNDRV_PCM_INFO_PAUSE |*/
				SNDRV_PCM_INFO_RESUME,
	.formats =		SNDRV_PCM_FMTBIT_U8 | SNDRV_PCM_FMTBIT_S16_LE,
	.rates =		SNDRV_PCM_RATE_KNOT/*24k*/ | SNDRV_PCM_RATE_8000_48000,
	.rate_min =		8000,
	.rate_max =		48000,
	.channels_min =		1,
	.channels_max =		2,
	.periods_min =		2,
	.periods_max =		1024,
	.buffer_bytes_max =	128 * 1024,
	.period_bytes_min =	256,
	.period_bytes_max =	128 * 1024,
};


/* set dma transfer size */
static int snd_nm256_pcm_hw_params(struct snd_pcm_substream *substream,
				   struct snd_pcm_hw_params *hw_params)
{
	/* area and addr are already set and unchanged */
	substream->runtime->dma_bytes = params_buffer_bytes(hw_params);
	return 0;
}

/*
 * open
 */
static void snd_nm256_setup_stream(struct nm256 *chip, struct nm256_stream *s,
				   struct snd_pcm_substream *substream,
				   struct snd_pcm_hardware *hw_ptr)
{
	struct snd_pcm_runtime *runtime = substream->runtime;

	s->running = 0;
	runtime->hw = *hw_ptr;
	runtime->hw.buffer_bytes_max = s->bufsize;
	runtime->hw.period_bytes_max = s->bufsize / 2;
	runtime->dma_area = (void __force *) s->bufptr;
	runtime->dma_addr = s->bufptr_addr;
	runtime->dma_bytes = s->bufsize;
	runtime->private_data = s;
	s->substream = substream;

	snd_pcm_set_sync(substream);
	snd_pcm_hw_constraint_list(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
				   &constraints_rates);
}

static int
snd_nm256_playback_open(struct snd_pcm_substream *substream)
{
	struct nm256 *chip = snd_pcm_substream_chip(substream);

	if (snd_nm256_acquire_irq(chip) < 0)
		return -EBUSY;
	snd_nm256_setup_stream(chip, &chip->streams[SNDRV_PCM_STREAM_PLAYBACK],
			       substream, &snd_nm256_playback);
	return 0;
}

static int
snd_nm256_capture_open(struct snd_pcm_substream *substream)
{
	struct nm256 *chip = snd_pcm_substream_chip(substream);

	if (snd_nm256_acquire_irq(chip) < 0)
		return -EBUSY;
	snd_nm256_setup_stream(chip, &chip->streams[SNDRV_PCM_STREAM_CAPTURE],
			       substream, &snd_nm256_capture);
	return 0;
}

/*
 * close - we don't have to do special..
 */
static int
snd_nm256_playback_close(struct snd_pcm_substream *substream)
{
	struct nm256 *chip = snd_pcm_substream_chip(substream);

	snd_nm256_release_irq(chip);
	return 0;
}