hda_intel.c

一个Linux下的软猫驱动

static int azx_setup_controller(azx_t *chip, azx_dev_t *azx_dev)
{
	unsigned char val;
	int timeout;

//printk(KERN_DEBUG"%s: %p tag=%d bufsize=%d fmt=0x%x\n", __FUNCTION__, azx_dev, (int)azx_dev->stream_tag, azx_dev->bufsize, (unsigned int)azx_dev->format_val);
	/* make sure the run bit is zero for SD */
	azx_sd_writeb(azx_dev, SD_CTL, azx_sd_readb(azx_dev, SD_CTL) & ~SD_CTL_DMA_START);
	/* reset stream */
	azx_sd_writeb(azx_dev, SD_CTL, azx_sd_readb(azx_dev, SD_CTL) | SD_CTL_STREAM_RESET);
	udelay(3);
	timeout = 300;
	while (!((val = azx_sd_readb(azx_dev, SD_CTL)) & SD_CTL_STREAM_RESET) &&
	       --timeout)
		;
	val &= ~SD_CTL_STREAM_RESET;
	azx_sd_writeb(azx_dev, SD_CTL, val);
	udelay(3);

	timeout = 300;
	/* waiting for hardware to report that the stream is out of reset */
	while (((val = azx_sd_readb(azx_dev, SD_CTL)) & SD_CTL_STREAM_RESET) &&
	       --timeout)
		;

	/* program the stream_tag */
	azx_sd_writel(azx_dev, SD_CTL,
		      (azx_sd_readl(azx_dev, SD_CTL) & ~SD_CTL_STREAM_TAG_MASK) |
		      (azx_dev->stream_tag << SD_CTL_STREAM_TAG_SHIFT));

	/* program the length of samples in cyclic buffer */
	azx_sd_writel(azx_dev, SD_CBL, azx_dev->bufsize);

	/* program the stream format */
	/* this value needs to be the same as the one programmed */
	azx_sd_writew(azx_dev, SD_FORMAT, azx_dev->format_val);

	/* program the stream LVI (last valid index) of the BDL */
	azx_sd_writew(azx_dev, SD_LVI, azx_dev->frags - 1);

	/* program the BDL address */
	/* lower BDL address */
	azx_sd_writel(azx_dev, SD_BDLPL, (u32)azx_dev->bdl_addr);
	/* upper BDL address */
	azx_sd_writel(azx_dev, SD_BDLPU, upper_32bit(azx_dev->bdl_addr));

	/* enable the position buffer */
	if (! (azx_readl(chip, DPLBASE) & ICH6_DPLBASE_ENABLE))
		azx_writel(chip, DPLBASE, (u32)chip->posbuf.addr | ICH6_DPLBASE_ENABLE);

	/* set the interrupt enable bits in the descriptor control register */
	azx_sd_writel(azx_dev, SD_CTL, azx_sd_readl(azx_dev, SD_CTL) | SD_INT_MASK);

	return 0;
}


/*
 * Codec initialization
 */

static int __devinit azx_codec_create(azx_t *chip, const char *model)
{
	struct hda_bus_template bus_temp;
	int c, codecs, err;

	memset(&bus_temp, 0, sizeof(bus_temp));
	bus_temp.private_data = chip;
	bus_temp.modelname = model;
	bus_temp.pci = chip->pci;
	bus_temp.ops.command = azx_send_cmd;
	bus_temp.ops.get_response = azx_get_response;
	bus_temp.ops.get_wallclock = azx_get_wallclock;
	bus_temp.ops.get_linkpos = azx_get_linkpos;

	if ((err = snd_hda_bus_new(chip->card, &bus_temp, &chip->bus)) < 0)
		return err;

	codecs = 0;
	for (c = 0; c < AZX_MAX_CODECS; c++) {
		if (chip->codec_mask & (1 << c)) {
			err = snd_hda_codec_new(chip->bus, c, NULL);
			if (err < 0)
				continue;
			codecs++;
		}
	}
	if (! codecs) {
		snd_printk(KERN_ERR SFX "no codecs initialized\n");
		return -ENXIO;
	}

	return 0;
}


/*
 * PCM support
 */

/* assign a stream for the PCM */
static inline azx_dev_t *azx_assign_device(azx_t *chip, int stream)
{
	int dev, i, nums;
	if (stream == SNDRV_PCM_STREAM_PLAYBACK) {
		dev = chip->playback_index_offset;
		nums = chip->playback_streams;
	} else {
		dev = chip->capture_index_offset;
		nums = chip->capture_streams;
	}
	for (i = 0; i < nums; i++, dev++)
		if (! chip->azx_dev[dev].opened) {
			chip->azx_dev[dev].opened = 1;
			return &chip->azx_dev[dev];
		}
	return NULL;
}

/* release the assigned stream */
static inline void azx_release_device(azx_dev_t *azx_dev)
{
//printk(KERN_ERR"%s dev=%p\n", __FUNCTION__, azx_dev);
	azx_dev->opened = 0;
}

static snd_pcm_hardware_t azx_pcm_hw = {
	.info =			(SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED |
				 SNDRV_PCM_INFO_BLOCK_TRANSFER |
				 SNDRV_PCM_INFO_MMAP_VALID |
				 SNDRV_PCM_INFO_PAUSE /*|*/
				 /*SNDRV_PCM_INFO_RESUME*/),
	.formats =		SNDRV_PCM_FMTBIT_S16_LE,
	.rates =		SNDRV_PCM_RATE_48000,
	.rate_min =		48000,
	.rate_max =		48000,
	.channels_min =		2,
	.channels_max =		2,
	.buffer_bytes_max =	AZX_MAX_BUF_SIZE,
	.period_bytes_min =	128,
	.period_bytes_max =	AZX_MAX_BUF_SIZE / 2,
	.periods_min =		2,
	.periods_max =		AZX_MAX_FRAG,
	.fifo_size =		0,
};

struct azx_pcm {
	azx_t *chip;
	struct hda_codec *codec;
	struct hda_pcm_stream *hinfo[2];
};

static int azx_pcm_open(snd_pcm_substream_t *substream)
{
	struct azx_pcm *apcm = snd_pcm_substream_chip(substream);
	struct hda_pcm_stream *hinfo = apcm->hinfo[substream->stream];
	azx_t *chip = apcm->chip;
	azx_dev_t *azx_dev;
	snd_pcm_runtime_t *runtime = substream->runtime;
	unsigned long flags;
	int err;

	down(&chip->open_mutex);
	azx_dev = azx_assign_device(chip, substream->stream);
	if (azx_dev == NULL) {
		up(&chip->open_mutex);
		return -EBUSY;
	}
	runtime->hw = azx_pcm_hw;
	runtime->hw.channels_min = hinfo->channels_min;
	runtime->hw.channels_max = hinfo->channels_max;
	runtime->hw.formats = hinfo->formats;
	runtime->hw.rates = hinfo->rates;
	snd_pcm_limit_hw_rates(runtime);
	snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
	if ((err = hinfo->ops.open(hinfo, apcm->codec, substream)) < 0) {
		azx_release_device(azx_dev);
		up(&chip->open_mutex);
		return err;
	}
	spin_lock_irqsave(&chip->reg_lock, flags);
	azx_dev->substream = substream;
	azx_dev->running = 0;
	spin_unlock_irqrestore(&chip->reg_lock, flags);

	runtime->private_data = azx_dev;
	up(&chip->open_mutex);
	return 0;
}

static int azx_pcm_close(snd_pcm_substream_t *substream)
{
	struct azx_pcm *apcm = snd_pcm_substream_chip(substream);
	struct hda_pcm_stream *hinfo = apcm->hinfo[substream->stream];
	azx_t *chip = apcm->chip;
	azx_dev_t *azx_dev = get_azx_dev(substream);
	unsigned long flags;

//printk(KERN_DEBUG"%s: %p\n", __FUNCTION__, substream);
	down(&chip->open_mutex);
	spin_lock_irqsave(&chip->reg_lock, flags);
	azx_dev->substream = NULL;
	azx_dev->running = 0;
	spin_unlock_irqrestore(&chip->reg_lock, flags);
	azx_release_device(azx_dev);
	hinfo->ops.close(hinfo, apcm->codec, substream);
	up(&chip->open_mutex);
	return 0;
}

static int azx_pcm_hw_params(snd_pcm_substream_t *substream, snd_pcm_hw_params_t *hw_params)
{
	return snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(hw_params));
}

static int azx_pcm_hw_free(snd_pcm_substream_t *substream)
{
	struct azx_pcm *apcm = snd_pcm_substream_chip(substream);
	azx_dev_t *azx_dev = get_azx_dev(substream);
	struct hda_pcm_stream *hinfo = apcm->hinfo[substream->stream];

//printk(KERN_DEBUG"%s: %p\n", __FUNCTION__, substream);
	/* reset BDL address */
	azx_sd_writel(azx_dev, SD_BDLPL, 0);
	azx_sd_writel(azx_dev, SD_BDLPU, 0);
	azx_sd_writel(azx_dev, SD_CTL, 0);

	hinfo->ops.cleanup(hinfo, apcm->codec, substream);

	return snd_pcm_lib_free_pages(substream);
}

static int azx_pcm_prepare(snd_pcm_substream_t *substream)
{
	struct azx_pcm *apcm = snd_pcm_substream_chip(substream);
	azx_t *chip = apcm->chip;
	azx_dev_t *azx_dev = get_azx_dev(substream);
	struct hda_pcm_stream *hinfo = apcm->hinfo[substream->stream];
	snd_pcm_runtime_t *runtime = substream->runtime;

	azx_dev->bufsize = snd_pcm_lib_buffer_bytes(substream);
	azx_dev->fragsize = snd_pcm_lib_period_bytes(substream);
	azx_dev->frags = azx_dev->bufsize / azx_dev->fragsize;
	azx_dev->format_val = snd_hda_calc_stream_format(runtime->rate,
							 runtime->channels,
							 runtime->format,
							 hinfo->maxbps);
	if (! azx_dev->format_val) {
		snd_printk(KERN_ERR SFX "invalid format_val, rate=%d, ch=%d, format=%d\n",
			   runtime->rate, runtime->channels, runtime->format);
		return -EINVAL;
	}

	snd_printdd("azx_pcm_prepare: bufsize=0x%x, fragsize=0x%x, format=0x%x\n",
		    azx_dev->bufsize, azx_dev->fragsize, azx_dev->format_val);
	azx_setup_periods(azx_dev);
	azx_setup_controller(chip, azx_dev);
	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
		azx_dev->fifo_size = azx_sd_readw(azx_dev, SD_FIFOSIZE) + 1;
	else
		azx_dev->fifo_size = 0;
	azx_dev->last_pos = 0;

//	runtime->hw.fifo_size = azx_sd_readw(azx_dev, SD_FIFOSIZE);

	return hinfo->ops.prepare(hinfo, apcm->codec, azx_dev->stream_tag,
				  azx_dev->format_val, substream);
}

static int azx_pcm_trigger(snd_pcm_substream_t *substream, int cmd)
{
	struct azx_pcm *apcm = snd_pcm_substream_chip(substream);
	azx_dev_t *azx_dev = get_azx_dev(substream);
	azx_t *chip = apcm->chip;
	int err = 0;

	spin_lock(&chip->reg_lock);
	switch (cmd) {
	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
	case SNDRV_PCM_TRIGGER_RESUME:
	case SNDRV_PCM_TRIGGER_START:
		azx_stream_start(chip, azx_dev);
		azx_dev->running = 1;
		break;
	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
	case SNDRV_PCM_TRIGGER_SUSPEND:
	case SNDRV_PCM_TRIGGER_STOP:
		azx_stream_stop(chip, azx_dev);
		azx_dev->running = 0;
		break;
	default:
		err = -EINVAL;
	}
	spin_unlock(&chip->reg_lock);
	if (cmd == SNDRV_PCM_TRIGGER_PAUSE_PUSH ||
	    cmd == SNDRV_PCM_TRIGGER_SUSPEND ||
	    cmd == SNDRV_PCM_TRIGGER_STOP) {
		int timeout = 5000;
		while (azx_sd_readb(azx_dev, SD_CTL) & SD_CTL_DMA_START && --timeout)
			;
	}
	return err;
}

static snd_pcm_uframes_t azx_pcm_pointer(snd_pcm_substream_t *substream)
{
	struct azx_pcm *apcm = snd_pcm_substream_chip(substream);
	azx_t *chip = apcm->chip;
	azx_dev_t *azx_dev = get_azx_dev(substream);
	unsigned int pos;

	if (chip->position_fix == POS_FIX_POSBUF) {
		/* use the position buffer */
		pos = *azx_dev->posbuf;
	} else {
		/* read LPIB */
		pos = azx_sd_readl(azx_dev, SD_LPIB);
		if (chip->position_fix == POS_FIX_FIFO)
			pos += azx_dev->fifo_size;
#if 0 /* disabled temprarily, auto-correction doesn't work well... */
		else if (chip->position_fix == POS_FIX_AUTO && azx_dev->period_updating) {
			/* check the validity of DMA position */
			unsigned int diff = 0;
			azx_dev->last_pos += azx_dev->fragsize;
			if (azx_dev->last_pos > pos)
				diff = azx_dev->last_pos - pos;
			if (azx_dev->last_pos >= azx_dev->bufsize) {
				if (pos < azx_dev->fragsize)
					diff = 0;
				azx_dev->last_pos = 0;
			}
			if (diff > 0 && diff <= azx_dev->fifo_size)
				pos += azx_dev->fifo_size;
			else {
				snd_printdd(KERN_INFO "hda_intel: DMA position fix %d, switching to posbuf\n", diff);
				chip->position_fix = POS_FIX_POSBUF;
				pos = *azx_dev->posbuf;
			}
			azx_dev->period_updating = 0;
		}
#else
		else if (chip->position_fix == POS_FIX_AUTO)
			pos += azx_dev->fifo_size;
#endif
	}
	if (pos >= azx_dev->bufsize)
		pos = 0;
	return bytes_to_frames(substream->runtime, pos);
}

static snd_pcm_ops_t azx_pcm_ops = {
	.open = azx_pcm_open,
	.close = azx_pcm_close,
	.ioctl = snd_pcm_lib_ioctl,
	.hw_params = azx_pcm_hw_params,
	.hw_free = azx_pcm_hw_free,
	.prepare = azx_pcm_prepare,
	.trigger = azx_pcm_trigger,
	.pointer = azx_pcm_pointer,
};

static void azx_pcm_free(snd_pcm_t *pcm)
{
//printk(KERN_DEBUG"%s: %p\n", __FUNCTION__, pcm);
	kfree(pcm->private_data);
}

static int __devinit create_codec_pcm(azx_t *chip, struct hda_codec *codec,
				      struct hda_pcm *cpcm, int pcm_dev)
{
	int err;
	snd_pcm_t *pcm;
	struct azx_pcm *apcm;

	snd_assert(cpcm->stream[0].substreams || cpcm->stream[1].substreams, return -EINVAL);
	snd_assert(cpcm->name, return -EINVAL);

	err = snd_pcm_new(chip->card, cpcm->name, pcm_dev,
			  cpcm->stream[0].substreams, cpcm->stream[1].substreams,
			  &pcm);
	if (err < 0)
		return err;
	strcpy(pcm->name, cpcm->name);
	apcm = kmalloc(sizeof(*apcm), GFP_KERNEL);
	if (apcm == NULL)
		return -ENOMEM;
	apcm->chip = chip;
	apcm->codec = codec;
	apcm->hinfo[0] = &cpcm->stream[0];
	apcm->hinfo[1] = &cpcm->stream[1];
	pcm->private_data = apcm;
	pcm->private_free = azx_pcm_free;
	if (cpcm->stream[0].substreams)
		snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &azx_pcm_ops);
	if (cpcm->stream[1].substreams)
		snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &azx_pcm_ops);
	snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV,
					      snd_dma_pci_data(chip->pci),
					      1024 * 64, 1024 * 128);
	cpcm->pcm = pcm;
	chip->pcm[pcm_dev] = pcm;
	chip->pcm_devs = pcm_dev + 1;

	return 0;
}

static int __devinit azx_pcm_create(azx_t *chip)
{
	struct list_head *p;
	struct hda_codec *codec;
	int c, err;
	int pcm_dev;

	if ((err = snd_hda_build_pcms(chip->bus)) < 0)
		return err;

	/* create audio PCMs */
	pcm_dev = 0;
	list_for_each(p, &chip->bus->codec_list) {
		codec = list_entry(p, struct hda_codec, list);
		for (c = 0; c < codec->num_pcms; c++) {
			if (codec->pcm_info[c].is_modem)
				continue; /* create later */
			if (pcm_dev >= AZX_MAX_AUDIO_PCMS) {
				snd_printk(KERN_ERR SFX "Too many audio PCMs\n");
				return -EINVAL;
			}
			err = create_codec_pcm(chip, codec, &codec->pcm_info[c], pcm_dev);
			if (err < 0)
				return err;
			pcm_dev++;
		}
	}