via82cxxx_audio.c

iis s3c2410-uda1341语音系统的 开发

		}
	}
	set_current_state(TASK_RUNNING);
	remove_wait_queue(&chan->wait, &wait);
	if (ret)
		goto out;

	/* Now that we have a buffer we can read from, send
	 * as much as sample data possible to userspace.
	 */
	while ((count > 0) && (chan->slop_len < chan->frag_size)) {
		size_t slop_left = chan->frag_size - chan->slop_len;
		void *base = chan->pgtbl[n / (PAGE_SIZE / chan->frag_size)].cpuaddr;
		unsigned ofs = n % (PAGE_SIZE / chan->frag_size);

		size = (count < slop_left) ? count : slop_left;
		if (copy_to_user (userbuf,
				  base + ofs + chan->slop_len,
				  size)) {
			ret = -EFAULT;
			goto out;
		}

		count -= size;
		chan->slop_len += size;
		userbuf += size;
	}

	/* If we didn't copy the buffer completely to userspace,
	 * stop now.
	 */
	if (chan->slop_len < chan->frag_size)
		goto out;

	/*
	 * If we get to this point, we copied one buffer completely
	 * to userspace, give the buffer back to the hardware.
	 */

	/* advance channel software pointer to point to
	 * the next buffer from which we will copy
	 */
	if (chan->sw_ptr == (chan->frag_number - 1))
		chan->sw_ptr = 0;
	else
		chan->sw_ptr++;

	/* mark one less buffer waiting to be processed */
	assert (atomic_read (&chan->n_frags) > 0);
	atomic_dec (&chan->n_frags);

	/* we are at a block boundary, there is no fragment data */
	chan->slop_len = 0;

	DPRINTK ("Flushed block %u, sw_ptr now %u, n_frags now %d\n",
		n, chan->sw_ptr, atomic_read (&chan->n_frags));

	DPRINTK ("regs==%02X %02X %02X %08X %08X %08X %08X\n",
		 inb (card->baseaddr + 0x00),
		 inb (card->baseaddr + 0x01),
		 inb (card->baseaddr + 0x02),
		 inl (card->baseaddr + 0x04),
		 inl (card->baseaddr + 0x0C),
		 inl (card->baseaddr + 0x80),
		 inl (card->baseaddr + 0x84));

	if (count > 0)
		goto handle_one_block;

out:
	return (userbuf != orig_userbuf) ? (userbuf - orig_userbuf) : ret;
}


static ssize_t via_dsp_read(struct file *file, char *buffer, size_t count, loff_t *ppos)
{
	struct via_info *card;
	int nonblock = (file->f_flags & O_NONBLOCK);
	int rc;

	DPRINTK ("ENTER, file=%p, buffer=%p, count=%u, ppos=%lu\n",
		 file, buffer, count, ppos ? ((unsigned long)*ppos) : 0);

	assert (file != NULL);
	assert (buffer != NULL);
	card = file->private_data;
	assert (card != NULL);

	if (ppos != &file->f_pos) {
		DPRINTK ("EXIT, returning -ESPIPE\n");
		return -ESPIPE;
	}

	rc = via_syscall_down (card, nonblock);
	if (rc) goto out;

	if (card->ch_in.is_mapped) {
		rc = -ENXIO;
		goto out_up;
	}

	via_chan_set_buffering(card, &card->ch_in, -1);
        rc = via_chan_buffer_init (card, &card->ch_in);

	if (rc)
		goto out_up;

	rc = via_dsp_do_read (card, buffer, count, nonblock);

out_up:
	up (&card->syscall_sem);
out:
	DPRINTK ("EXIT, returning %ld\n",(long) rc);
	return rc;
}


static ssize_t via_dsp_do_write (struct via_info *card,
				 const char *userbuf, size_t count,
				 int nonblock)
{
        DECLARE_WAITQUEUE(wait, current);
	const char *orig_userbuf = userbuf;
	struct via_channel *chan = &card->ch_out;
	volatile struct via_sgd_table *sgtable = chan->sgtable;
	size_t size;
	int n, tmp;
	ssize_t ret = 0;

handle_one_block:
	/* just to be a nice neighbor */
	/* Thomas Sailer:
	 * But also to ourselves, release semaphore if we do so */
	if (current->need_resched) {
		up(&card->syscall_sem);
		schedule ();
		ret = via_syscall_down (card, nonblock);
		if (ret)
			goto out;
	}

	/* grab current channel fragment pointer.  In the case of
	 * playback, this is pointing to the next fragment that
	 * should receive data from userland.
	 */
	n = chan->sw_ptr;

	/* n_frags represents the number of fragments remaining
	 * to be filled by userspace.  Sleep until
	 * at least one fragment is available for our use.
	 */
	add_wait_queue(&chan->wait, &wait);
	for (;;) {
		__set_current_state(TASK_INTERRUPTIBLE);
		tmp = atomic_read (&chan->n_frags);
		assert (tmp >= 0);
		assert (tmp <= chan->frag_number);
		if (tmp)
			break;
		if (nonblock || !chan->is_active) {
			ret = -EAGAIN;
			break;
		}

		up(&card->syscall_sem);

		DPRINTK ("Sleeping on page %d, tmp==%d, ir==%d\n", n, tmp, chan->is_record);
		schedule();

		ret = via_syscall_down (card, nonblock);
		if (ret)
			break;

		if (signal_pending (current)) {
			ret = -ERESTARTSYS;
			break;
		}
	}
	set_current_state(TASK_RUNNING);
	remove_wait_queue(&chan->wait, &wait);
	if (ret)
		goto out;

	/* Now that we have at least one fragment we can write to, fill the buffer
	 * as much as possible with data from userspace.
	 */
	while ((count > 0) && (chan->slop_len < chan->frag_size)) {
		size_t slop_left = chan->frag_size - chan->slop_len;

		size = (count < slop_left) ? count : slop_left;
		if (copy_from_user (chan->pgtbl[n / (PAGE_SIZE / chan->frag_size)].cpuaddr + (n % (PAGE_SIZE / chan->frag_size)) * chan->frag_size + chan->slop_len,
				    userbuf, size)) {
			ret = -EFAULT;
			goto out;
		}

		count -= size;
		chan->slop_len += size;
		userbuf += size;
	}

	/* If we didn't fill up the buffer with data, stop now.
         * Put a 'stop' marker in the DMA table too, to tell the
         * audio hardware to stop if it gets here.
         */
	if (chan->slop_len < chan->frag_size) {
		sgtable[n].count = cpu_to_le32 (chan->slop_len | VIA_EOL | VIA_STOP);
		goto out;
	}

	/*
         * If we get to this point, we have filled a buffer with
         * audio data, flush the buffer to audio hardware.
         */

	/* Record the true size for the audio hardware to notice */
        if (n == (chan->frag_number - 1))
                sgtable[n].count = cpu_to_le32 (chan->frag_size | VIA_EOL);
        else
                sgtable[n].count = cpu_to_le32 (chan->frag_size | VIA_FLAG);

	/* advance channel software pointer to point to
	 * the next buffer we will fill with data
	 */
	if (chan->sw_ptr == (chan->frag_number - 1))
		chan->sw_ptr = 0;
	else
		chan->sw_ptr++;

	/* mark one less buffer as being available for userspace consumption */
	assert (atomic_read (&chan->n_frags) > 0);
	atomic_dec (&chan->n_frags);

	/* we are at a block boundary, there is no fragment data */
	chan->slop_len = 0;

	/* if SGD has not yet been started, start it */
	via_chan_maybe_start (chan);

	DPRINTK ("Flushed block %u, sw_ptr now %u, n_frags now %d\n",
		n, chan->sw_ptr, atomic_read (&chan->n_frags));

	DPRINTK ("regs==%02X %02X %02X %08X %08X %08X %08X\n",
		 inb (card->baseaddr + 0x00),
		 inb (card->baseaddr + 0x01),
		 inb (card->baseaddr + 0x02),
		 inl (card->baseaddr + 0x04),
		 inl (card->baseaddr + 0x0C),
		 inl (card->baseaddr + 0x80),
		 inl (card->baseaddr + 0x84));

	if (count > 0)
		goto handle_one_block;

out:
	return userbuf - orig_userbuf;
}


static ssize_t via_dsp_write(struct file *file, const char *buffer, size_t count, loff_t *ppos)
{
	struct via_info *card;
	ssize_t rc;
	int nonblock = (file->f_flags & O_NONBLOCK);

	DPRINTK ("ENTER, file=%p, buffer=%p, count=%u, ppos=%lu\n",
		 file, buffer, count, ppos ? ((unsigned long)*ppos) : 0);

	assert (file != NULL);
	assert (buffer != NULL);
	card = file->private_data;
	assert (card != NULL);

	if (ppos != &file->f_pos) {
		DPRINTK ("EXIT, returning -ESPIPE\n");
		return -ESPIPE;
	}

	rc = via_syscall_down (card, nonblock);
	if (rc) goto out;

	if (card->ch_out.is_mapped) {
		rc = -ENXIO;
		goto out_up;
	}

	via_chan_set_buffering(card, &card->ch_out, -1);
	rc = via_chan_buffer_init (card, &card->ch_out);

	if (rc)
		goto out_up;

	rc = via_dsp_do_write (card, buffer, count, nonblock);

out_up:
	up (&card->syscall_sem);
out:
	DPRINTK ("EXIT, returning %ld\n",(long) rc);
	return rc;
}


static unsigned int via_dsp_poll(struct file *file, struct poll_table_struct *wait)
{
	struct via_info *card;
	struct via_channel *chan;
	unsigned int mask = 0;

	DPRINTK ("ENTER\n");

	assert (file != NULL);
	card = file->private_data;
	assert (card != NULL);

	if (file->f_mode & FMODE_READ) {
		chan = &card->ch_in;
		if (sg_active (chan->iobase))
	                poll_wait(file, &chan->wait, wait);
		if (atomic_read (&chan->n_frags) > 0)
			mask |= POLLIN | POLLRDNORM;
	}

	if (file->f_mode & FMODE_WRITE) {
		chan = &card->ch_out;
		if (sg_active (chan->iobase))
	                poll_wait(file, &chan->wait, wait);
		if (atomic_read (&chan->n_frags) > 0)
			mask |= POLLOUT | POLLWRNORM;
	}

	DPRINTK ("EXIT, returning %u\n", mask);
	return mask;
}


/**
 *	via_dsp_drain_playback - sleep until all playback samples are flushed
 *	@card: Private info for specified board
 *	@chan: Channel to drain
 *	@nonblock: boolean, non-zero if O_NONBLOCK is set
 *
 *	Sleeps until all playback has been flushed to the audio
 *	hardware.
 *
 *	Locking: inside card->syscall_sem
 */

static int via_dsp_drain_playback (struct via_info *card,
				   struct via_channel *chan, int nonblock)
{
        DECLARE_WAITQUEUE(wait, current);
	int ret = 0;

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

	if (chan->slop_len > 0)
		via_chan_flush_frag (chan);

	if (atomic_read (&chan->n_frags) == chan->frag_number)
		goto out;

	via_chan_maybe_start (chan);

	add_wait_queue(&chan->wait, &wait);
	for (;;) {
		__set_current_state(TASK_INTERRUPTIBLE);
		if (atomic_read (&chan->n_frags) >= chan->frag_number)
			break;

		if (nonblock) {
			DPRINTK ("EXIT, returning -EAGAIN\n");
			ret = -EAGAIN;
			break;
		}

#ifdef VIA_DEBUG
		{
		u8 r40,r41,r42,r43,r44,r48;
		pci_read_config_byte (card->pdev, 0x40, &r40);
		pci_read_config_byte (card->pdev, 0x41, &r41);
		pci_read_config_byte (card->pdev, 0x42, &r42);
		pci_read_config_byte (card->pdev, 0x43, &r43);
		pci_read_config_byte (card->pdev, 0x44, &r44);
		pci_read_config_byte (card->pdev, 0x48, &r48);
		DPRINTK ("PCI config: %02X %02X %02X %02X %02X %02X\n",
			r40,r41,r42,r43,r44,r48);

		DPRINTK ("regs==%02X %02X %02X %08X %08X %08X %08X\n",
			 inb (card->baseaddr + 0x00),
			 inb (card->baseaddr + 0x01),
			 inb (card->baseaddr + 0x02),
			 inl (card->baseaddr + 0x04),
			 inl (card->baseaddr + 0x0C),
			 inl (card->baseaddr + 0x80),
			 inl (card->baseaddr + 0x84));
		}

		if (!chan->is_active)
			printk (KERN_ERR "sleeping but not active\n");
#endif

		up(&card->syscall_sem);

		DPRINTK ("sleeping, nbufs=%d\n", atomic_read (&chan->n_frags));
		schedule();

		if ((ret = via_syscall_down (card, nonblock)))
			break;

		if (signal_pending (current)) {
			DPRINTK ("EXIT, returning -ERESTARTSYS\n");
			ret = -ERESTARTSYS;
			break;
		}
	}
	set_current_state(TASK_RUNNING);
	remove_wait_queue(&chan->wait, &wait);

#ifdef VIA_DEBUG
	{
		u8 r40,r41,r42,r43,r44,r48;
		pci_read_config_byte (card->pdev, 0x40, &r40);
		pci_read_config_byte (card->pdev, 0x41, &r41);
		pci_read_config_byte (card->pdev, 0x42, &r42);
		pci_read_config_byte (card->pdev, 0x43, &r43);
		pci_read_config_byte (card->pdev, 0x44, &r44);
		pci_read_config_byte (card->pdev, 0x48, &r48);
		DPRINTK ("PCI config: %02X %02X %02X %02X %02X %02X\n",
			r40,r41,r42,r43,r44,r48);

		DPRINTK ("regs==%02X %02X %02X %08X %08X %08X %08X\n",
			 inb (card->baseaddr + 0x00),
			 inb (card->baseaddr + 0x01),
			 inb (card->baseaddr + 0x02),
			 inl (card->baseaddr + 0x04),
			 inl (card->baseaddr + 0x0C),
			 inl (card->baseaddr + 0x80),
			 inl (card->baseaddr + 0x84));

		DPRINTK ("final nbufs=%d\n", atomic_read (&chan->n_frags));
	}
#endif

out:
	DPRINTK ("EXIT, returning %d\n", ret);
	return ret;
}


/**
 *	via_dsp_ioctl_space - get information about channel buffering
 *	@card: Private info for specified board
 *	@chan: pointer to channel-specific info
 *	@arg: user buffer for returned information
 *
 *	Handles SNDCTL_DSP_GETISPACE and SNDCTL_DSP_GETOSPACE.
 *
 *	Locking: inside card->syscall_sem
 */

static int via_dsp_ioctl_space (struct via_info *card,
				struct via_channel *chan,
				void *arg)
{
	audio_buf_info info;

	via_chan_set_buffering(card, chan, -1);

	info.fragstotal = chan->frag_number;
	info.fragsize = chan->frag_size;

	/* number of full fragments we can read/write without blocking */
	info.fragments = atomic_read (&chan->n_frags);

	if ((chan->slop_len % chan->frag_size > 0) && (info.fragments > 0))
		info.fragments--;

	/* number of bytes that can be read or written immediately
	 * without blocking.
	 */
	info.bytes = (info.fragments * chan->frag_size);
	if (chan->slop_len % chan->frag_size > 0)
		info.bytes += chan->frag_size - (chan->slop_len % chan->frag_size);

	DPRINTK ("EXIT, returning fragstotal=%d, fragsize=%d, fragments=%d, bytes=%d\n",
		info.fragstotal,
		info.fragsize,
		info.fragments,
		info.bytes);

	return copy_to_user (arg, &info, sizeof (info));
}


/**
 *	via_dsp_ioctl_ptr - get information about hardware buffer ptr
 *	@card: Private info for specified board
 *	@chan: pointer to channel-specific info
 *	@arg: user buffer for returned information
 *
 *	Handles SNDCTL_DSP_GETIPTR and SNDCTL_DSP_GETOPTR.
 *
 *	Locking: inside card->syscall_sem
 */

static int via_dsp_ioctl_ptr (struct via_info *card