aaci.c

linux 内核源代码

	int ret;

	/*
	 * Add rule describing channel dependency.
	 */
	ret = snd_pcm_hw_rule_add(substream->runtime, 0,
				  SNDRV_PCM_HW_PARAM_CHANNELS,
				  aaci_rule_channels, aaci,
				  SNDRV_PCM_HW_PARAM_CHANNELS, -1);
	if (ret)
		return ret;

	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
		ret = __aaci_pcm_open(aaci, substream, &aaci->playback);
	} else {
		ret = __aaci_pcm_open(aaci, substream, &aaci->capture);
	}
	return ret;
}

static int aaci_pcm_playback_hw_params(struct snd_pcm_substream *substream,
				       struct snd_pcm_hw_params *params)
{
	struct aaci *aaci = substream->private_data;
	struct aaci_runtime *aacirun = substream->runtime->private_data;
	unsigned int channels = params_channels(params);
	int ret;

	WARN_ON(channels >= ARRAY_SIZE(channels_to_txmask) ||
		!channels_to_txmask[channels]);

	ret = aaci_pcm_hw_params(substream, aacirun, params);

	/*
	 * Enable FIFO, compact mode, 16 bits per sample.
	 * FIXME: double rate slots?
	 */
	if (ret >= 0) {
		aacirun->cr = CR_FEN | CR_COMPACT | CR_SZ16;
		aacirun->cr |= channels_to_txmask[channels];

		aacirun->fifosz	= aaci->fifosize * 4;
		if (aacirun->cr & CR_COMPACT)
			aacirun->fifosz >>= 1;
	}
	return ret;
}

static void aaci_pcm_playback_stop(struct aaci_runtime *aacirun)
{
	u32 ie;

	ie = readl(aacirun->base + AACI_IE);
	ie &= ~(IE_URIE|IE_TXIE);
	writel(ie, aacirun->base + AACI_IE);
	aacirun->cr &= ~CR_EN;
	aaci_chan_wait_ready(aacirun);
	writel(aacirun->cr, aacirun->base + AACI_TXCR);
}

static void aaci_pcm_playback_start(struct aaci_runtime *aacirun)
{
	u32 ie;

	aaci_chan_wait_ready(aacirun);
	aacirun->cr |= CR_EN;

	ie = readl(aacirun->base + AACI_IE);
	ie |= IE_URIE | IE_TXIE;
	writel(ie, aacirun->base + AACI_IE);
	writel(aacirun->cr, aacirun->base + AACI_TXCR);
}

static int aaci_pcm_playback_trigger(struct snd_pcm_substream *substream, int cmd)
{
	struct aaci *aaci = substream->private_data;
	struct aaci_runtime *aacirun = substream->runtime->private_data;
	unsigned long flags;
	int ret = 0;

	spin_lock_irqsave(&aaci->lock, flags);
	switch (cmd) {
	case SNDRV_PCM_TRIGGER_START:
		aaci_pcm_playback_start(aacirun);
		break;

	case SNDRV_PCM_TRIGGER_RESUME:
		aaci_pcm_playback_start(aacirun);
		break;

	case SNDRV_PCM_TRIGGER_STOP:
		aaci_pcm_playback_stop(aacirun);
		break;

	case SNDRV_PCM_TRIGGER_SUSPEND:
		aaci_pcm_playback_stop(aacirun);
		break;

	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
		break;

	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
		break;

	default:
		ret = -EINVAL;
	}
	spin_unlock_irqrestore(&aaci->lock, flags);

	return ret;
}

static struct snd_pcm_ops aaci_playback_ops = {
	.open		= aaci_pcm_open,
	.close		= aaci_pcm_close,
	.ioctl		= snd_pcm_lib_ioctl,
	.hw_params	= aaci_pcm_playback_hw_params,
	.hw_free	= aaci_pcm_hw_free,
	.prepare	= aaci_pcm_prepare,
	.trigger	= aaci_pcm_playback_trigger,
	.pointer	= aaci_pcm_pointer,
	.mmap		= aaci_pcm_mmap,
};

static int aaci_pcm_capture_hw_params(struct snd_pcm_substream *substream,
				      struct snd_pcm_hw_params *params)
{
	struct aaci *aaci = substream->private_data;
	struct aaci_runtime *aacirun = substream->runtime->private_data;
	int ret;

	ret = aaci_pcm_hw_params(substream, aacirun, params);

	if (ret >= 0) {
		aacirun->cr = CR_FEN | CR_COMPACT | CR_SZ16;

		/* Line in record: slot 3 and 4 */
		aacirun->cr |= CR_SL3 | CR_SL4;

		aacirun->fifosz = aaci->fifosize * 4;

		if (aacirun->cr & CR_COMPACT)
			aacirun->fifosz >>= 1;
	}
	return ret;
}

static void aaci_pcm_capture_stop(struct aaci_runtime *aacirun)
{
	u32 ie;

	aaci_chan_wait_ready(aacirun);

	ie = readl(aacirun->base + AACI_IE);
	ie &= ~(IE_ORIE | IE_RXIE);
	writel(ie, aacirun->base+AACI_IE);

	aacirun->cr &= ~CR_EN;

	writel(aacirun->cr, aacirun->base + AACI_RXCR);
}

static void aaci_pcm_capture_start(struct aaci_runtime *aacirun)
{
	u32 ie;

	aaci_chan_wait_ready(aacirun);

#ifdef DEBUG
	/* RX Timeout value: bits 28:17 in RXCR */
	aacirun->cr |= 0xf << 17;
#endif

	aacirun->cr |= CR_EN;
	writel(aacirun->cr, aacirun->base + AACI_RXCR);

	ie = readl(aacirun->base + AACI_IE);
	ie |= IE_ORIE |IE_RXIE; // overrun and rx interrupt -- half full
	writel(ie, aacirun->base + AACI_IE);
}

static int aaci_pcm_capture_trigger(struct snd_pcm_substream *substream, int cmd)
{
	struct aaci *aaci = substream->private_data;
	struct aaci_runtime *aacirun = substream->runtime->private_data;
	unsigned long flags;
	int ret = 0;

	spin_lock_irqsave(&aaci->lock, flags);

	switch (cmd) {
	case SNDRV_PCM_TRIGGER_START:
		aaci_pcm_capture_start(aacirun);
		break;

	case SNDRV_PCM_TRIGGER_RESUME:
		aaci_pcm_capture_start(aacirun);
		break;

	case SNDRV_PCM_TRIGGER_STOP:
		aaci_pcm_capture_stop(aacirun);
		break;

	case SNDRV_PCM_TRIGGER_SUSPEND:
		aaci_pcm_capture_stop(aacirun);
		break;

	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
		break;

	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
		break;

	default:
		ret = -EINVAL;
	}

	spin_unlock_irqrestore(&aaci->lock, flags);

	return ret;
}

static int aaci_pcm_capture_prepare(struct snd_pcm_substream *substream)
{
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct aaci *aaci = substream->private_data;

	aaci_pcm_prepare(substream);

	/* allow changing of sample rate */
	aaci_ac97_write(aaci->ac97, AC97_EXTENDED_STATUS, 0x0001); /* VRA */
	aaci_ac97_write(aaci->ac97, AC97_PCM_LR_ADC_RATE, runtime->rate);
	aaci_ac97_write(aaci->ac97, AC97_PCM_MIC_ADC_RATE, runtime->rate);

	/* Record select: Mic: 0, Aux: 3, Line: 4 */
	aaci_ac97_write(aaci->ac97, AC97_REC_SEL, 0x0404);

	return 0;
}

static struct snd_pcm_ops aaci_capture_ops = {
	.open		= aaci_pcm_open,
	.close		= aaci_pcm_close,
	.ioctl		= snd_pcm_lib_ioctl,
	.hw_params	= aaci_pcm_capture_hw_params,
	.hw_free	= aaci_pcm_hw_free,
	.prepare	= aaci_pcm_capture_prepare,
	.trigger	= aaci_pcm_capture_trigger,
	.pointer	= aaci_pcm_pointer,
	.mmap		= aaci_pcm_mmap,
};

/*
 * Power Management.
 */
#ifdef CONFIG_PM
static int aaci_do_suspend(struct snd_card *card, unsigned int state)
{
	struct aaci *aaci = card->private_data;
	snd_power_change_state(card, SNDRV_CTL_POWER_D3cold);
	snd_pcm_suspend_all(aaci->pcm);
	return 0;
}

static int aaci_do_resume(struct snd_card *card, unsigned int state)
{
	snd_power_change_state(card, SNDRV_CTL_POWER_D0);
	return 0;
}

static int aaci_suspend(struct amba_device *dev, pm_message_t state)
{
	struct snd_card *card = amba_get_drvdata(dev);
	return card ? aaci_do_suspend(card) : 0;
}

static int aaci_resume(struct amba_device *dev)
{
	struct snd_card *card = amba_get_drvdata(dev);
	return card ? aaci_do_resume(card) : 0;
}
#else
#define aaci_do_suspend		NULL
#define aaci_do_resume		NULL
#define aaci_suspend		NULL
#define aaci_resume		NULL
#endif


static struct ac97_pcm ac97_defs[] __devinitdata = {
	[0] = {	/* Front PCM */
		.exclusive = 1,
		.r = {
			[0] = {
				.slots	= (1 << AC97_SLOT_PCM_LEFT) |
					  (1 << AC97_SLOT_PCM_RIGHT) |
					  (1 << AC97_SLOT_PCM_CENTER) |
					  (1 << AC97_SLOT_PCM_SLEFT) |
					  (1 << AC97_SLOT_PCM_SRIGHT) |
					  (1 << AC97_SLOT_LFE),
			},
		},
	},
	[1] = {	/* PCM in */
		.stream = 1,
		.exclusive = 1,
		.r = {
			[0] = {
				.slots	= (1 << AC97_SLOT_PCM_LEFT) |
					  (1 << AC97_SLOT_PCM_RIGHT),
			},
		},
	},
	[2] = {	/* Mic in */
		.stream = 1,
		.exclusive = 1,
		.r = {
			[0] = {
				.slots	= (1 << AC97_SLOT_MIC),
			},
		},
	}
};

static struct snd_ac97_bus_ops aaci_bus_ops = {
	.write	= aaci_ac97_write,
	.read	= aaci_ac97_read,
};

static int __devinit aaci_probe_ac97(struct aaci *aaci)
{
	struct snd_ac97_template ac97_template;
	struct snd_ac97_bus *ac97_bus;
	struct snd_ac97 *ac97;
	int ret;

	/*
	 * Assert AACIRESET for 2us
	 */
	writel(0, aaci->base + AACI_RESET);
	udelay(2);
	writel(RESET_NRST, aaci->base + AACI_RESET);

	/*
	 * Give the AC'97 codec more than enough time
	 * to wake up. (42us = ~2 frames at 48kHz.)
	 */
	udelay(42);

	ret = snd_ac97_bus(aaci->card, 0, &aaci_bus_ops, aaci, &ac97_bus);
	if (ret)
		goto out;

	ac97_bus->clock = 48000;
	aaci->ac97_bus = ac97_bus;

	memset(&ac97_template, 0, sizeof(struct snd_ac97_template));
	ac97_template.private_data = aaci;
	ac97_template.num = 0;
	ac97_template.scaps = AC97_SCAP_SKIP_MODEM;

	ret = snd_ac97_mixer(ac97_bus, &ac97_template, &ac97);
	if (ret)
		goto out;
	aaci->ac97 = ac97;

	/*
	 * Disable AC97 PC Beep input on audio codecs.
	 */
	if (ac97_is_audio(ac97))
		snd_ac97_write_cache(ac97, AC97_PC_BEEP, 0x801e);

	ret = snd_ac97_pcm_assign(ac97_bus, ARRAY_SIZE(ac97_defs), ac97_defs);
	if (ret)
		goto out;

	aaci->playback.pcm = &ac97_bus->pcms[0];
	aaci->capture.pcm  = &ac97_bus->pcms[1];

 out:
	return ret;
}

static void aaci_free_card(struct snd_card *card)
{
	struct aaci *aaci = card->private_data;
	if (aaci->base)
		iounmap(aaci->base);
}

static struct aaci * __devinit aaci_init_card(struct amba_device *dev)
{
	struct aaci *aaci;
	struct snd_card *card;

	card = snd_card_new(SNDRV_DEFAULT_IDX1, SNDRV_DEFAULT_STR1,
			    THIS_MODULE, sizeof(struct aaci));
	if (card == NULL)
		return ERR_PTR(-ENOMEM);

	card->private_free = aaci_free_card;

	strlcpy(card->driver, DRIVER_NAME, sizeof(card->driver));
	strlcpy(card->shortname, "ARM AC'97 Interface", sizeof(card->shortname));
	snprintf(card->longname, sizeof(card->longname),
		 "%s at 0x%016llx, irq %d",
		 card->shortname, (unsigned long long)dev->res.start,
		 dev->irq[0]);

	aaci = card->private_data;
	mutex_init(&aaci->ac97_sem);
	spin_lock_init(&aaci->lock);
	aaci->card = card;
	aaci->dev = dev;

	/* Set MAINCR to allow slot 1 and 2 data IO */
	aaci->maincr = MAINCR_IE | MAINCR_SL1RXEN | MAINCR_SL1TXEN |
		       MAINCR_SL2RXEN | MAINCR_SL2TXEN;

	return aaci;
}

static int __devinit aaci_init_pcm(struct aaci *aaci)
{
	struct snd_pcm *pcm;
	int ret;

	ret = snd_pcm_new(aaci->card, "AACI AC'97", 0, 1, 1, &pcm);
	if (ret == 0) {
		aaci->pcm = pcm;
		pcm->private_data = aaci;
		pcm->info_flags = 0;

		strlcpy(pcm->name, DRIVER_NAME, sizeof(pcm->name));

		snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &aaci_playback_ops);
		snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &aaci_capture_ops);
	}

	return ret;
}

static unsigned int __devinit aaci_size_fifo(struct aaci *aaci)
{
	struct aaci_runtime *aacirun = &aaci->playback;
	int i;

	writel(CR_FEN | CR_SZ16 | CR_EN, aacirun->base + AACI_TXCR);

	for (i = 0; !(readl(aacirun->base + AACI_SR) & SR_TXFF) && i < 4096; i++)
		writel(0, aacirun->fifo);

	writel(0, aacirun->base + AACI_TXCR);

	/*
	 * Re-initialise the AACI after the FIFO depth test, to
	 * ensure that the FIFOs are empty.  Unfortunately, merely
	 * disabling the channel doesn't clear the FIFO.
	 */
	writel(aaci->maincr & ~MAINCR_IE, aaci->base + AACI_MAINCR);
	writel(aaci->maincr, aaci->base + AACI_MAINCR);

	/*
	 * If we hit 4096, we failed.  Go back to the specified
	 * fifo depth.
	 */
	if (i == 4096)
		i = 8;

	return i;
}

static int __devinit aaci_probe(struct amba_device *dev, void *id)
{
	struct aaci *aaci;
	int ret, i;

	ret = amba_request_regions(dev, NULL);
	if (ret)
		return ret;

	aaci = aaci_init_card(dev);
	if (IS_ERR(aaci)) {
		ret = PTR_ERR(aaci);
		goto out;
	}

	aaci->base = ioremap(dev->res.start, SZ_4K);
	if (!aaci->base) {
		ret = -ENOMEM;
		goto out;
	}

	/*
	 * Playback uses AACI channel 0
	 */
	aaci->playback.base = aaci->base + AACI_CSCH1;
	aaci->playback.fifo = aaci->base + AACI_DR1;

	/*
	 * Capture uses AACI channel 0
	 */
	aaci->capture.base = aaci->base + AACI_CSCH1;
	aaci->capture.fifo = aaci->base + AACI_DR1;

	for (i = 0; i < 4; i++) {
		void __iomem *base = aaci->base + i * 0x14;

		writel(0, base + AACI_IE);
		writel(0, base + AACI_TXCR);
		writel(0, base + AACI_RXCR);
	}

	writel(0x1fff, aaci->base + AACI_INTCLR);
	writel(aaci->maincr, aaci->base + AACI_MAINCR);

	ret = aaci_probe_ac97(aaci);
	if (ret)
		goto out;

	/*
	 * Size the FIFOs (must be multiple of 16).
	 */
	aaci->fifosize = aaci_size_fifo(aaci);
	if (aaci->fifosize & 15) {
		printk(KERN_WARNING "AACI: fifosize = %d not supported\n",
		       aaci->fifosize);
		ret = -ENODEV;
		goto out;
	}

	ret = aaci_init_pcm(aaci);
	if (ret)
		goto out;

	snd_card_set_dev(aaci->card, &dev->dev);

	ret = snd_card_register(aaci->card);
	if (ret == 0) {
		dev_info(&dev->dev, "%s, fifo %d\n", aaci->card->longname,
			 aaci->fifosize);
		amba_set_drvdata(dev, aaci->card);
		return ret;
	}

 out:
	if (aaci)
		snd_card_free(aaci->card);
	amba_release_regions(dev);
	return ret;
}

static int __devexit aaci_remove(struct amba_device *dev)
{
	struct snd_card *card = amba_get_drvdata(dev);

	amba_set_drvdata(dev, NULL);

	if (card) {
		struct aaci *aaci = card->private_data;
		writel(0, aaci->base + AACI_MAINCR);

		snd_card_free(card);
		amba_release_regions(dev);
	}

	return 0;
}

static struct amba_id aaci_ids[] = {
	{
		.id	= 0x00041041,
		.mask	= 0x000fffff,
	},
	{ 0, 0 },
};

static struct amba_driver aaci_driver = {
	.drv		= {
		.name	= DRIVER_NAME,
	},
	.probe		= aaci_probe,
	.remove		= __devexit_p(aaci_remove),
	.suspend	= aaci_suspend,
	.resume		= aaci_resume,
	.id_table	= aaci_ids,
};

static int __init aaci_init(void)
{
	return amba_driver_register(&aaci_driver);
}

static void __exit aaci_exit(void)
{
	amba_driver_unregister(&aaci_driver);
}

module_init(aaci_init);
module_exit(aaci_exit);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("ARM PrimeCell PL041 Advanced Audio CODEC Interface driver");