via82cxxx_audio.c

iis s3c2410-uda1341语音系统的 开发

	/*
	 * clear any existing stops / flags (sanity check mainly)
	 */
	via_chan_status_clear (card->baseaddr + VIA_BASE0_PCM_OUT_CHAN);
	via_chan_status_clear (card->baseaddr + VIA_BASE0_PCM_IN_CHAN);
	via_chan_status_clear (card->baseaddr + VIA_BASE0_FM_OUT_CHAN);

	/*
	 * clear any enabled interrupt bits
	 */
	tmp = inb (card->baseaddr + VIA_BASE0_PCM_OUT_CHAN_TYPE);
	new_tmp = tmp & ~(VIA_IRQ_ON_FLAG|VIA_IRQ_ON_EOL|VIA_RESTART_SGD_ON_EOL);
	if (tmp != new_tmp)
		outb (0, card->baseaddr + VIA_BASE0_PCM_OUT_CHAN_TYPE);

	tmp = inb (card->baseaddr + VIA_BASE0_PCM_IN_CHAN_TYPE);
	new_tmp = tmp & ~(VIA_IRQ_ON_FLAG|VIA_IRQ_ON_EOL|VIA_RESTART_SGD_ON_EOL);
	if (tmp != new_tmp)
		outb (0, card->baseaddr + VIA_BASE0_PCM_IN_CHAN_TYPE);

	tmp = inb (card->baseaddr + VIA_BASE0_FM_OUT_CHAN_TYPE);
	new_tmp = tmp & ~(VIA_IRQ_ON_FLAG|VIA_IRQ_ON_EOL|VIA_RESTART_SGD_ON_EOL);
	if (tmp != new_tmp)
		outb (0, card->baseaddr + VIA_BASE0_FM_OUT_CHAN_TYPE);

	udelay(10);

	/*
	 * clear any existing flags
	 */
	via_chan_status_clear (card->baseaddr + VIA_BASE0_PCM_OUT_CHAN);
	via_chan_status_clear (card->baseaddr + VIA_BASE0_PCM_IN_CHAN);
	via_chan_status_clear (card->baseaddr + VIA_BASE0_FM_OUT_CHAN);

	DPRINTK ("EXIT\n");
}


/**
 *	via_set_rate - Set PCM rate for given channel
 *	@ac97: Pointer to generic codec info struct
 *	@chan: Private info for specified channel
 *	@rate: Desired PCM sample rate, in Khz
 *
 *	Sets the PCM sample rate for a channel.
 *
 *	Values for @rate are clamped to a range of 4000 Khz through 48000 Khz,
 *	due to hardware constraints.
 */

static int via_set_rate (struct ac97_codec *ac97,
			 struct via_channel *chan, unsigned rate)
{
	struct via_info *card = ac97->private_data;
	int rate_reg;

	DPRINTK ("ENTER, rate = %d\n", rate);

	if (chan->rate == rate)
		goto out;
	if (card->locked_rate) {
		chan->rate = 48000;
		goto out;
	}

	if (rate > 48000)		rate = 48000;
	if (rate < 4000) 		rate = 4000;

	rate_reg = chan->is_record ? AC97_PCM_LR_ADC_RATE :
			    AC97_PCM_FRONT_DAC_RATE;

	via_ac97_write_reg (ac97, AC97_POWER_CONTROL,
		(via_ac97_read_reg (ac97, AC97_POWER_CONTROL) & ~0x0200) |
		0x0200);

	via_ac97_write_reg (ac97, rate_reg, rate);

	via_ac97_write_reg (ac97, AC97_POWER_CONTROL,
		via_ac97_read_reg (ac97, AC97_POWER_CONTROL) & ~0x0200);

	udelay (10);

	/* the hardware might return a value different than what we
	 * passed to it, so read the rate value back from hardware
	 * to see what we came up with
	 */
	chan->rate = via_ac97_read_reg (ac97, rate_reg);

	if (chan->rate == 0) {
		card->locked_rate = 1;
		chan->rate = 48000;
		printk (KERN_WARNING PFX "Codec rate locked at 48Khz\n");
	}

out:
	DPRINTK ("EXIT, returning rate %d Hz\n", chan->rate);
	return chan->rate;
}


/****************************************************************
 *
 * Channel-specific operations
 *
 *
 */


/**
 *	via_chan_init_defaults - Initialize a struct via_channel
 *	@card: Private audio chip info
 *	@chan: Channel to be initialized
 *
 *	Zero @chan, and then set all static defaults for the structure.
 */

static void via_chan_init_defaults (struct via_info *card, struct via_channel *chan)
{
	memset (chan, 0, sizeof (*chan));

	if (chan == &card->ch_out) {
		chan->name = "PCM-OUT";
		chan->iobase = card->baseaddr + VIA_BASE0_PCM_OUT_CHAN;
	} else if (chan == &card->ch_in) {
		chan->name = "PCM-IN";
		chan->iobase = card->baseaddr + VIA_BASE0_PCM_IN_CHAN;
		chan->is_record = 1;
	} else if (chan == &card->ch_fm) {
		chan->name = "PCM-OUT-FM";
		chan->iobase = card->baseaddr + VIA_BASE0_FM_OUT_CHAN;
	} else {
		BUG();
	}

	init_waitqueue_head (&chan->wait);

	chan->pcm_fmt = VIA_PCM_FMT_MASK;
	chan->is_enabled = 1;

	chan->frag_number = 0;
        chan->frag_size = 0;
	atomic_set(&chan->n_frags, 0);
	atomic_set (&chan->hw_ptr, 0);
}

/**
 *      via_chan_init - Initialize PCM channel
 *      @card: Private audio chip info
 *      @chan: Channel to be initialized
 *
 *      Performs some of the preparations necessary to begin
 *      using a PCM channel.
 *
 *      Currently the preparations consist in
 *      setting the
 *      PCM channel to a known state.
 */


static void via_chan_init (struct via_info *card, struct via_channel *chan)
{

        DPRINTK ("ENTER\n");

	/* bzero channel structure, and init members to defaults */
        via_chan_init_defaults (card, chan);

        /* stop any existing channel output */
        via_chan_clear (card, chan);
        via_chan_status_clear (chan->iobase);
        via_chan_pcm_fmt (chan, 1);

	DPRINTK ("EXIT\n");
}

/**
 *	via_chan_buffer_init - Initialize PCM channel buffer
 *	@card: Private audio chip info
 *	@chan: Channel to be initialized
 *
 *	Performs some of the preparations necessary to begin
 *	using a PCM channel.
 *
 *	Currently the preparations include allocating the
 *	scatter-gather DMA table and buffers,
 *	and passing the
 *	address of the DMA table to the hardware.
 *
 *	Note that special care is taken when passing the
 *	DMA table address to hardware, because it was found
 *	during driver development that the hardware did not
 *	always "take" the address.
 */

static int via_chan_buffer_init (struct via_info *card, struct via_channel *chan)
{
	int page, offset;
	int i;

	DPRINTK ("ENTER\n");

	if (chan->sgtable != NULL) {
		DPRINTK ("EXIT\n");
		return 0;
	}

	/* alloc DMA-able memory for scatter-gather table */
	chan->sgtable = pci_alloc_consistent (card->pdev,
		(sizeof (struct via_sgd_table) * chan->frag_number),
		&chan->sgt_handle);
	if (!chan->sgtable) {
		printk (KERN_ERR PFX "DMA table alloc fail, aborting\n");
		DPRINTK ("EXIT\n");
		return -ENOMEM;
	}

	memset ((void*)chan->sgtable, 0,
		(sizeof (struct via_sgd_table) * chan->frag_number));

	/* alloc DMA-able memory for scatter-gather buffers */

	chan->page_number = (chan->frag_number * chan->frag_size) / PAGE_SIZE +
			    (((chan->frag_number * chan->frag_size) % PAGE_SIZE) ? 1 : 0);

	for (i = 0; i < chan->page_number; i++) {
		chan->pgtbl[i].cpuaddr = pci_alloc_consistent (card->pdev, PAGE_SIZE,
					      &chan->pgtbl[i].handle);

		if (!chan->pgtbl[i].cpuaddr) {
			chan->page_number = i;
			goto err_out_nomem;
		}

#ifndef VIA_NDEBUG
                memset (chan->pgtbl[i].cpuaddr, 0xBC, chan->frag_size);
#endif

#if 1
                DPRINTK ("dmabuf_pg #%d (h=%lx, v2p=%lx, a=%p)\n",
			i, (long)chan->pgtbl[i].handle,
			virt_to_phys(chan->pgtbl[i].cpuaddr),
			chan->pgtbl[i].cpuaddr);
#endif
	}

	for (i = 0; i < chan->frag_number; i++) {

		page = i / (PAGE_SIZE / chan->frag_size);
		offset = (i % (PAGE_SIZE / chan->frag_size)) * chan->frag_size;

		chan->sgtable[i].count = cpu_to_le32 (chan->frag_size | VIA_FLAG);
		chan->sgtable[i].addr = cpu_to_le32 (chan->pgtbl[page].handle + offset);

#if 1
		DPRINTK ("dmabuf #%d (32(h)=%lx)\n",
			 i,
			 (long)chan->sgtable[i].addr);
#endif
	}

	/* overwrite the last buffer information */
	chan->sgtable[chan->frag_number - 1].count = cpu_to_le32 (chan->frag_size | VIA_EOL);

	/* set location of DMA-able scatter-gather info table */
	DPRINTK ("outl (0x%X, 0x%04lX)\n",
		chan->sgt_handle, chan->iobase + VIA_PCM_TABLE_ADDR);

	via_ac97_wait_idle (card);
	outl (chan->sgt_handle, chan->iobase + VIA_PCM_TABLE_ADDR);
	udelay (20);
	via_ac97_wait_idle (card);

	DPRINTK ("inl (0x%lX) = %x\n",
		chan->iobase + VIA_PCM_TABLE_ADDR,
		inl(chan->iobase + VIA_PCM_TABLE_ADDR));

	DPRINTK ("EXIT\n");
	return 0;

err_out_nomem:
	printk (KERN_ERR PFX "DMA buffer alloc fail, aborting\n");
	via_chan_buffer_free (card, chan);
	DPRINTK ("EXIT\n");
	return -ENOMEM;
}


/**
 *	via_chan_free - Release a PCM channel
 *	@card: Private audio chip info
 *	@chan: Channel to be released
 *
 *	Performs all the functions necessary to clean up
 *	an initialized channel.
 *
 *	Currently these functions include disabled any
 *	active DMA operations, setting the PCM channel
 *	back to a known state, and releasing any allocated
 *	sound buffers.
 */

static void via_chan_free (struct via_info *card, struct via_channel *chan)
{
	DPRINTK ("ENTER\n");

	spin_lock_irq (&card->lock);

	/* stop any existing channel output */
	via_chan_status_clear (chan->iobase);
	via_chan_stop (chan->iobase);
	via_chan_status_clear (chan->iobase);

	spin_unlock_irq (&card->lock);

	synchronize_irq();

	DPRINTK ("EXIT\n");
}

static void via_chan_buffer_free (struct via_info *card, struct via_channel *chan)
{
	int i;

        DPRINTK ("ENTER\n");

	/* zero location of DMA-able scatter-gather info table */
	via_ac97_wait_idle(card);
	outl (0, chan->iobase + VIA_PCM_TABLE_ADDR);

	for (i = 0; i < chan->page_number; i++)
		if (chan->pgtbl[i].cpuaddr) {
			pci_free_consistent (card->pdev, PAGE_SIZE,
					     chan->pgtbl[i].cpuaddr,
					     chan->pgtbl[i].handle);
			chan->pgtbl[i].cpuaddr = NULL;
			chan->pgtbl[i].handle = 0;
		}

	chan->page_number = 0;

	if (chan->sgtable) {
		pci_free_consistent (card->pdev,
			(sizeof (struct via_sgd_table) * chan->frag_number),
			(void*)chan->sgtable, chan->sgt_handle);
		chan->sgtable = NULL;
	}

	DPRINTK ("EXIT\n");
}


/**
 *	via_chan_pcm_fmt - Update PCM channel settings
 *	@chan: Channel to be updated
 *	@reset: Boolean.  If non-zero, channel will be reset
 *		to 8-bit mono mode.
 *
 *	Stores the settings of the current PCM format,
 *	8-bit or 16-bit, and mono/stereo, into the
 *	hardware settings for the specified channel.
 *	If @reset is non-zero, the channel is reset
 *	to 8-bit mono mode.  Otherwise, the channel
 *	is set to the values stored in the channel
 *	information struct @chan.
 */

static void via_chan_pcm_fmt (struct via_channel *chan, int reset)
{
	DPRINTK ("ENTER, pcm_fmt=0x%02X, reset=%s\n",
		 chan->pcm_fmt, reset ? "yes" : "no");

	assert (chan != NULL);

	if (reset)
		/* reset to 8-bit mono mode */
		chan->pcm_fmt = 0;

	/* enable interrupts on FLAG and EOL */
	chan->pcm_fmt |= VIA_CHAN_TYPE_MASK;

	/* if we are recording, enable recording fifo bit */
	if (chan->is_record)
		chan->pcm_fmt |= VIA_PCM_REC_FIFO;
	/* set interrupt select bits where applicable (PCM in & out channels) */
	if (!chan->is_record)
		chan->pcm_fmt |= VIA_CHAN_TYPE_INT_SELECT;

	outb (chan->pcm_fmt, chan->iobase + VIA_PCM_TYPE);

	DPRINTK ("EXIT, pcm_fmt = 0x%02X, reg = 0x%02X\n",
		 chan->pcm_fmt,
		 inb (chan->iobase + VIA_PCM_TYPE));
}


/**
 *	via_chan_clear - Stop DMA channel operation, and reset pointers
 *	@card: the chip to accessed
 *	@chan: Channel to be cleared
 *
 *	Call via_chan_stop to halt DMA operations, and then resets
 *	all software pointers which track DMA operation.
 */

static void via_chan_clear (struct via_info *card, struct via_channel *chan)
{
	DPRINTK ("ENTER\n");
	via_chan_stop (chan->iobase);
	via_chan_buffer_free(card, chan);
	chan->is_active = 0;
	chan->is_mapped = 0;
	chan->is_enabled = 1;
	chan->slop_len = 0;
	chan->sw_ptr = 0;
	chan->n_irqs = 0;
	atomic_set (&chan->hw_ptr, 0);
	DPRINTK ("EXIT\n");
}


/**
 *	via_chan_set_speed - Set PCM sample rate for given channel
 *	@card: Private info for specified board
 *	@chan: Channel whose sample rate will be adjusted
 *	@val: New sample rate, in Khz
 *
 *	Helper function for the %SNDCTL_DSP_SPEED ioctl.  OSS semantics
 *	demand that all audio operations halt (if they are not already
 *	halted) when the %SNDCTL_DSP_SPEED is given.
 *
 *	This function halts all audio operations for the given channel
 *	@chan, and then calls via_set_rate to set the audio hardware
 *	to the new rate.
 */

static int via_chan_set_speed (struct via_info *card,
			       struct via_channel *chan, int val)
{
	DPRINTK ("ENTER, requested rate = %d\n", val);

	via_chan_clear (card, chan);

	val = via_set_rate (&card->ac97, chan, val);

	DPRINTK ("EXIT, returning %d\n", val);
	return val;
}


/**
 *	via_chan_set_fmt - Set PCM sample size for given channel
 *	@card: Private info for specified board
 *	@chan: Channel whose sample size will be adjusted
 *	@val: New sample size, use the %AFMT_xxx constants
 *
 *	Helper function for the %SNDCTL_DSP_SETFMT ioctl.  OSS semantics
 *	demand that all audio operations halt (if they are not already
 *	halted) when the %SNDCTL_DSP_SETFMT is given.
 *
 *	This function halts all audio operations for the given channel
 *	@chan, and then calls via_chan_pcm_fmt to set the audio hardware
 *	to the new sample size, either 8-bit or 16-bit.
 */

static int via_chan_set_fmt (struct via_info *card,
			     struct via_channel *chan, int val)
{
	DPRINTK ("ENTER, val=%s\n",
		 val == AFMT_U8 ? "AFMT_U8" :
	 	 val == AFMT_S16_LE ? "AFMT_S16_LE" :
		 "unknown");

	via_chan_clear (card, chan);

	assert (val != AFMT_QUERY); /* this case is handled elsewhere */

	switch (val) {
	case AFMT_S16_LE:
		if ((chan->pcm_fmt & VIA_PCM_FMT_16BIT) == 0) {
			chan->pcm_fmt |= VIA_PCM_FMT_16BIT;
			via_chan_pcm_fmt (chan, 0);
		}
		break;

	case AFMT_U8:
		if (chan->pcm_fmt & VIA_PCM_FMT_16BIT) {
			chan->pcm_fmt &= ~VIA_PCM_FMT_16BIT;
			via_chan_pcm_fmt (chan, 0);
		}
		break;

	default:
		DPRINTK ("unknown AFMT: 0x%X\n", val);
		val = AFMT_S16_LE;
	}

	DPRINTK ("EXIT\n");
	return val;
}


/**
 *	via_chan_set_stereo - Enable or disable stereo for a DMA channel
 *	@card: Private info for specified board
 *	@chan: Channel whose stereo setting will be adjusted
 *	@val: New sample size, use the %AFMT_xxx constants
 *
 *	Helper function for the %SNDCTL_DSP_CHANNELS and %SNDCTL_DSP_STEREO ioctls.  OSS semantics
 *	demand that all audio operations halt (if they are not already