atiixp.c

linux 内核源代码

	int timeout = 1000;

	while (atiixp_read(chip, PHYS_OUT_ADDR) & ATI_REG_PHYS_OUT_ADDR_EN) {
		if (! timeout--) {
			snd_printk(KERN_WARNING "atiixp: codec acquire timeout\n");
			return -EBUSY;
		}
		udelay(1);
	}
	return 0;
}

static unsigned short snd_atiixp_codec_read(struct atiixp *chip, unsigned short codec, unsigned short reg)
{
	unsigned int data;
	int timeout;

	if (snd_atiixp_acquire_codec(chip) < 0)
		return 0xffff;
	data = (reg << ATI_REG_PHYS_OUT_ADDR_SHIFT) |
		ATI_REG_PHYS_OUT_ADDR_EN |
		ATI_REG_PHYS_OUT_RW |
		codec;
	atiixp_write(chip, PHYS_OUT_ADDR, data);
	if (snd_atiixp_acquire_codec(chip) < 0)
		return 0xffff;
	timeout = 1000;
	do {
		data = atiixp_read(chip, PHYS_IN_ADDR);
		if (data & ATI_REG_PHYS_IN_READ_FLAG)
			return data >> ATI_REG_PHYS_IN_DATA_SHIFT;
		udelay(1);
	} while (--timeout);
	/* time out may happen during reset */
	if (reg < 0x7c)
		snd_printk(KERN_WARNING "atiixp: codec read timeout (reg %x)\n", reg);
	return 0xffff;
}


static void snd_atiixp_codec_write(struct atiixp *chip, unsigned short codec,
				   unsigned short reg, unsigned short val)
{
	unsigned int data;
    
	if (snd_atiixp_acquire_codec(chip) < 0)
		return;
	data = ((unsigned int)val << ATI_REG_PHYS_OUT_DATA_SHIFT) |
		((unsigned int)reg << ATI_REG_PHYS_OUT_ADDR_SHIFT) |
		ATI_REG_PHYS_OUT_ADDR_EN | codec;
	atiixp_write(chip, PHYS_OUT_ADDR, data);
}


static unsigned short snd_atiixp_ac97_read(struct snd_ac97 *ac97,
					   unsigned short reg)
{
	struct atiixp *chip = ac97->private_data;
	return snd_atiixp_codec_read(chip, ac97->num, reg);
    
}

static void snd_atiixp_ac97_write(struct snd_ac97 *ac97, unsigned short reg,
				  unsigned short val)
{
	struct atiixp *chip = ac97->private_data;
	snd_atiixp_codec_write(chip, ac97->num, reg, val);
}

/*
 * reset AC link
 */
static int snd_atiixp_aclink_reset(struct atiixp *chip)
{
	int timeout;

	/* reset powerdoewn */
	if (atiixp_update(chip, CMD, ATI_REG_CMD_POWERDOWN, 0))
		udelay(10);

	/* perform a software reset */
	atiixp_update(chip, CMD, ATI_REG_CMD_AC_SOFT_RESET, ATI_REG_CMD_AC_SOFT_RESET);
	atiixp_read(chip, CMD);
	udelay(10);
	atiixp_update(chip, CMD, ATI_REG_CMD_AC_SOFT_RESET, 0);
    
	timeout = 10;
	while (! (atiixp_read(chip, CMD) & ATI_REG_CMD_ACLINK_ACTIVE)) {
		/* do a hard reset */
		atiixp_update(chip, CMD, ATI_REG_CMD_AC_SYNC|ATI_REG_CMD_AC_RESET,
			      ATI_REG_CMD_AC_SYNC);
		atiixp_read(chip, CMD);
		mdelay(1);
		atiixp_update(chip, CMD, ATI_REG_CMD_AC_RESET, ATI_REG_CMD_AC_RESET);
		if (--timeout) {
			snd_printk(KERN_ERR "atiixp: codec reset timeout\n");
			break;
		}
	}

	/* deassert RESET and assert SYNC to make sure */
	atiixp_update(chip, CMD, ATI_REG_CMD_AC_SYNC|ATI_REG_CMD_AC_RESET,
		      ATI_REG_CMD_AC_SYNC|ATI_REG_CMD_AC_RESET);

	return 0;
}

#ifdef CONFIG_PM
static int snd_atiixp_aclink_down(struct atiixp *chip)
{
	// if (atiixp_read(chip, MODEM_MIRROR) & 0x1) /* modem running, too? */
	//	return -EBUSY;
	atiixp_update(chip, CMD,
		     ATI_REG_CMD_POWERDOWN | ATI_REG_CMD_AC_RESET,
		     ATI_REG_CMD_POWERDOWN);
	return 0;
}
#endif

/*
 * auto-detection of codecs
 *
 * the IXP chip can generate interrupts for the non-existing codecs.
 * NEW_FRAME interrupt is used to make sure that the interrupt is generated
 * even if all three codecs are connected.
 */

#define ALL_CODEC_NOT_READY \
	    (ATI_REG_ISR_CODEC0_NOT_READY |\
	     ATI_REG_ISR_CODEC1_NOT_READY |\
	     ATI_REG_ISR_CODEC2_NOT_READY)
#define CODEC_CHECK_BITS (ALL_CODEC_NOT_READY|ATI_REG_ISR_NEW_FRAME)

static int ac97_probing_bugs(struct pci_dev *pci)
{
	const struct snd_pci_quirk *q;

	q = snd_pci_quirk_lookup(pci, atiixp_quirks);
	if (q) {
		snd_printdd(KERN_INFO "Atiixp quirk for %s.  "
			    "Forcing codec %d\n", q->name, q->value);
		return q->value;
	}
	/* this hardware doesn't need workarounds.  Probe for codec */
	return -1;
}

static int snd_atiixp_codec_detect(struct atiixp *chip)
{
	int timeout;

	chip->codec_not_ready_bits = 0;
	if (ac97_codec == -1)
		ac97_codec = ac97_probing_bugs(chip->pci);
	if (ac97_codec >= 0) {
		chip->codec_not_ready_bits |= 
			CODEC_CHECK_BITS ^ (1 << (ac97_codec + 10));
		return 0;
	}

	atiixp_write(chip, IER, CODEC_CHECK_BITS);
	/* wait for the interrupts */
	timeout = 50;
	while (timeout-- > 0) {
		mdelay(1);
		if (chip->codec_not_ready_bits)
			break;
	}
	atiixp_write(chip, IER, 0); /* disable irqs */

	if ((chip->codec_not_ready_bits & ALL_CODEC_NOT_READY) == ALL_CODEC_NOT_READY) {
		snd_printk(KERN_ERR "atiixp: no codec detected!\n");
		return -ENXIO;
	}
	return 0;
}


/*
 * enable DMA and irqs
 */
static int snd_atiixp_chip_start(struct atiixp *chip)
{
	unsigned int reg;

	/* set up spdif, enable burst mode */
	reg = atiixp_read(chip, CMD);
	reg |= 0x02 << ATI_REG_CMD_SPDF_THRESHOLD_SHIFT;
	reg |= ATI_REG_CMD_BURST_EN;
	atiixp_write(chip, CMD, reg);

	reg = atiixp_read(chip, SPDF_CMD);
	reg &= ~(ATI_REG_SPDF_CMD_LFSR|ATI_REG_SPDF_CMD_SINGLE_CH);
	atiixp_write(chip, SPDF_CMD, reg);

	/* clear all interrupt source */
	atiixp_write(chip, ISR, 0xffffffff);
	/* enable irqs */
	atiixp_write(chip, IER,
		     ATI_REG_IER_IO_STATUS_EN |
		     ATI_REG_IER_IN_XRUN_EN |
		     ATI_REG_IER_OUT_XRUN_EN |
		     ATI_REG_IER_SPDF_XRUN_EN |
		     ATI_REG_IER_SPDF_STATUS_EN);
	return 0;
}


/*
 * disable DMA and IRQs
 */
static int snd_atiixp_chip_stop(struct atiixp *chip)
{
	/* clear interrupt source */
	atiixp_write(chip, ISR, atiixp_read(chip, ISR));
	/* disable irqs */
	atiixp_write(chip, IER, 0);
	return 0;
}


/*
 * PCM section
 */

/*
 * pointer callback simplly reads XXX_DMA_DT_CUR register as the current
 * position.  when SG-buffer is implemented, the offset must be calculated
 * correctly...
 */
static snd_pcm_uframes_t snd_atiixp_pcm_pointer(struct snd_pcm_substream *substream)
{
	struct atiixp *chip = snd_pcm_substream_chip(substream);
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct atiixp_dma *dma = runtime->private_data;
	unsigned int curptr;
	int timeout = 1000;

	while (timeout--) {
		curptr = readl(chip->remap_addr + dma->ops->dt_cur);
		if (curptr < dma->buf_addr)
			continue;
		curptr -= dma->buf_addr;
		if (curptr >= dma->buf_bytes)
			continue;
		return bytes_to_frames(runtime, curptr);
	}
	snd_printd("atiixp: invalid DMA pointer read 0x%x (buf=%x)\n",
		   readl(chip->remap_addr + dma->ops->dt_cur), dma->buf_addr);
	return 0;
}

/*
 * XRUN detected, and stop the PCM substream
 */
static void snd_atiixp_xrun_dma(struct atiixp *chip, struct atiixp_dma *dma)
{
	if (! dma->substream || ! dma->running)
		return;
	snd_printdd("atiixp: XRUN detected (DMA %d)\n", dma->ops->type);
	snd_pcm_stop(dma->substream, SNDRV_PCM_STATE_XRUN);
}

/*
 * the period ack.  update the substream.
 */
static void snd_atiixp_update_dma(struct atiixp *chip, struct atiixp_dma *dma)
{
	if (! dma->substream || ! dma->running)
		return;
	snd_pcm_period_elapsed(dma->substream);
}

/* set BUS_BUSY interrupt bit if any DMA is running */
/* call with spinlock held */
static void snd_atiixp_check_bus_busy(struct atiixp *chip)
{
	unsigned int bus_busy;
	if (atiixp_read(chip, CMD) & (ATI_REG_CMD_SEND_EN |
				      ATI_REG_CMD_RECEIVE_EN |
				      ATI_REG_CMD_SPDF_OUT_EN))
		bus_busy = ATI_REG_IER_SET_BUS_BUSY;
	else
		bus_busy = 0;
	atiixp_update(chip, IER, ATI_REG_IER_SET_BUS_BUSY, bus_busy);
}

/* common trigger callback
 * calling the lowlevel callbacks in it
 */
static int snd_atiixp_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
{
	struct atiixp *chip = snd_pcm_substream_chip(substream);
	struct atiixp_dma *dma = substream->runtime->private_data;
	int err = 0;

	snd_assert(dma->ops->enable_transfer && dma->ops->flush_dma, return -EINVAL);

	spin_lock(&chip->reg_lock);
	switch (cmd) {
	case SNDRV_PCM_TRIGGER_START:
	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
	case SNDRV_PCM_TRIGGER_RESUME:
		dma->ops->enable_transfer(chip, 1);
		dma->running = 1;
		dma->suspended = 0;
		break;
	case SNDRV_PCM_TRIGGER_STOP:
	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
	case SNDRV_PCM_TRIGGER_SUSPEND:
		dma->ops->enable_transfer(chip, 0);
		dma->running = 0;
		dma->suspended = cmd == SNDRV_PCM_TRIGGER_SUSPEND;
		break;
	default:
		err = -EINVAL;
		break;
	}
	if (! err) {
		snd_atiixp_check_bus_busy(chip);
		if (cmd == SNDRV_PCM_TRIGGER_STOP) {
			dma->ops->flush_dma(chip);
			snd_atiixp_check_bus_busy(chip);
		}
	}
	spin_unlock(&chip->reg_lock);
	return err;
}


/*
 * lowlevel callbacks for each DMA type
 *
 * every callback is supposed to be called in chip->reg_lock spinlock
 */

/* flush FIFO of analog OUT DMA */
static void atiixp_out_flush_dma(struct atiixp *chip)
{
	atiixp_write(chip, FIFO_FLUSH, ATI_REG_FIFO_OUT_FLUSH);
}

/* enable/disable analog OUT DMA */
static void atiixp_out_enable_dma(struct atiixp *chip, int on)
{
	unsigned int data;
	data = atiixp_read(chip, CMD);
	if (on) {
		if (data & ATI_REG_CMD_OUT_DMA_EN)
			return;
		atiixp_out_flush_dma(chip);
		data |= ATI_REG_CMD_OUT_DMA_EN;
	} else
		data &= ~ATI_REG_CMD_OUT_DMA_EN;
	atiixp_write(chip, CMD, data);
}

/* start/stop transfer over OUT DMA */
static void atiixp_out_enable_transfer(struct atiixp *chip, int on)
{
	atiixp_update(chip, CMD, ATI_REG_CMD_SEND_EN,
		      on ? ATI_REG_CMD_SEND_EN : 0);
}

/* enable/disable analog IN DMA */
static void atiixp_in_enable_dma(struct atiixp *chip, int on)
{
	atiixp_update(chip, CMD, ATI_REG_CMD_IN_DMA_EN,
		      on ? ATI_REG_CMD_IN_DMA_EN : 0);
}

/* start/stop analog IN DMA */
static void atiixp_in_enable_transfer(struct atiixp *chip, int on)
{
	if (on) {
		unsigned int data = atiixp_read(chip, CMD);
		if (! (data & ATI_REG_CMD_RECEIVE_EN)) {
			data |= ATI_REG_CMD_RECEIVE_EN;
#if 0 /* FIXME: this causes the endless loop */
			/* wait until slot 3/4 are finished */
			while ((atiixp_read(chip, COUNTER) &
				ATI_REG_COUNTER_SLOT) != 5)
				;
#endif
			atiixp_write(chip, CMD, data);
		}
	} else
		atiixp_update(chip, CMD, ATI_REG_CMD_RECEIVE_EN, 0);
}

/* flush FIFO of analog IN DMA */
static void atiixp_in_flush_dma(struct atiixp *chip)
{
	atiixp_write(chip, FIFO_FLUSH, ATI_REG_FIFO_IN_FLUSH);
}

/* enable/disable SPDIF OUT DMA */
static void atiixp_spdif_enable_dma(struct atiixp *chip, int on)
{
	atiixp_update(chip, CMD, ATI_REG_CMD_SPDF_DMA_EN,
		      on ? ATI_REG_CMD_SPDF_DMA_EN : 0);
}

/* start/stop SPDIF OUT DMA */
static void atiixp_spdif_enable_transfer(struct atiixp *chip, int on)
{
	unsigned int data;
	data = atiixp_read(chip, CMD);
	if (on)
		data |= ATI_REG_CMD_SPDF_OUT_EN;
	else
		data &= ~ATI_REG_CMD_SPDF_OUT_EN;
	atiixp_write(chip, CMD, data);
}

/* flush FIFO of SPDIF OUT DMA */
static void atiixp_spdif_flush_dma(struct atiixp *chip)
{
	int timeout;

	/* DMA off, transfer on */
	atiixp_spdif_enable_dma(chip, 0);
	atiixp_spdif_enable_transfer(chip, 1);
	
	timeout = 100;
	do {
		if (! (atiixp_read(chip, SPDF_DMA_DT_SIZE) & ATI_REG_DMA_FIFO_USED))
			break;
		udelay(1);