via82cxxx_audio.c

来自「linux 内核源代码」· C语言 代码 · 共 2,515 行 · 第 1/5 页

			tmp8 |= VIA_CR48_FM_TRAP_TO_NMI;
			pci_write_config_byte (card->pdev, VIA_FM_NMI_CTRL, tmp8);
		}
		if (request_irq (card->pdev->irq, via_interrupt, IRQF_SHARED, VIA_MODULE_NAME, card)) {
			printk (KERN_ERR PFX "unable to obtain IRQ %d, aborting\n",
				card->pdev->irq);
			DPRINTK ("EXIT, returning -EBUSY\n");
			return -EBUSY;
		}
	}
	else 
	{
		if (request_irq (card->pdev->irq, via_new_interrupt, IRQF_SHARED, VIA_MODULE_NAME, card)) {
			printk (KERN_ERR PFX "unable to obtain IRQ %d, aborting\n",
				card->pdev->irq);
			DPRINTK ("EXIT, returning -EBUSY\n");
			return -EBUSY;
		}
	}

	DPRINTK ("EXIT, returning 0\n");
	return 0;
}


/****************************************************************
 *
 * OSS DSP device
 *
 */

static const struct file_operations via_dsp_fops = {
	.owner		= THIS_MODULE,
	.open		= via_dsp_open,
	.release	= via_dsp_release,
	.read		= via_dsp_read,
	.write		= via_dsp_write,
	.poll		= via_dsp_poll,
	.llseek		= no_llseek,
	.ioctl		= via_dsp_ioctl,
	.mmap		= via_dsp_mmap,
};


static int __devinit via_dsp_init (struct via_info *card)
{
	u8 tmp8;

	DPRINTK ("ENTER\n");

	assert (card != NULL);

	if(card->legacy)
	{
		/* turn off legacy features, if not already */
		pci_read_config_byte (card->pdev, VIA_FUNC_ENABLE, &tmp8);
		if (tmp8 & (VIA_CR42_SB_ENABLE |  VIA_CR42_FM_ENABLE)) {
			tmp8 &= ~(VIA_CR42_SB_ENABLE | VIA_CR42_FM_ENABLE);
			pci_write_config_byte (card->pdev, VIA_FUNC_ENABLE, tmp8);
		}
	}

	via_stop_everything (card);

	card->dev_dsp = register_sound_dsp (&via_dsp_fops, -1);
	if (card->dev_dsp < 0) {
		DPRINTK ("EXIT, returning -ENODEV\n");
		return -ENODEV;
	}
	DPRINTK ("EXIT, returning 0\n");
	return 0;
}


static void via_dsp_cleanup (struct via_info *card)
{
	DPRINTK ("ENTER\n");

	assert (card != NULL);
	assert (card->dev_dsp >= 0);

	via_stop_everything (card);

	unregister_sound_dsp (card->dev_dsp);

	DPRINTK ("EXIT\n");
}


static struct page * via_mm_nopage (struct vm_area_struct * vma,
				    unsigned long address, int *type)
{
	struct via_info *card = vma->vm_private_data;
	struct via_channel *chan = &card->ch_out;
	unsigned long max_bufs;
	struct page *dmapage;
	unsigned long pgoff;
	int rd, wr;

	DPRINTK ("ENTER, start %lXh, ofs %lXh, pgoff %ld, addr %lXh\n",
		 vma->vm_start,
		 address - vma->vm_start,
		 (address - vma->vm_start) >> PAGE_SHIFT,
		 address);

        if (address > vma->vm_end) {
		DPRINTK ("EXIT, returning NOPAGE_SIGBUS\n");
		return NOPAGE_SIGBUS; /* Disallow mremap */
	}
        if (!card) {
		DPRINTK ("EXIT, returning NOPAGE_SIGBUS\n");
		return NOPAGE_SIGBUS;	/* Nothing allocated */
	}

	pgoff = vma->vm_pgoff + ((address - vma->vm_start) >> PAGE_SHIFT);
	rd = card->ch_in.is_mapped;
	wr = card->ch_out.is_mapped;

	max_bufs = chan->frag_number;
	if (rd && wr)
		max_bufs *= 2;
	if (pgoff >= max_bufs)
		return NOPAGE_SIGBUS;

	/* if full-duplex (read+write) and we have two sets of bufs,
	 * then the playback buffers come first, sez soundcard.c */
	if (pgoff >= chan->page_number) {
		pgoff -= chan->page_number;
		chan = &card->ch_in;
	} else if (!wr)
		chan = &card->ch_in;

	assert ((((unsigned long)chan->pgtbl[pgoff].cpuaddr) % PAGE_SIZE) == 0);

	dmapage = virt_to_page (chan->pgtbl[pgoff].cpuaddr);
	DPRINTK ("EXIT, returning page %p for cpuaddr %lXh\n",
		 dmapage, (unsigned long) chan->pgtbl[pgoff].cpuaddr);
	get_page (dmapage);
	if (type)
		*type = VM_FAULT_MINOR;
	return dmapage;
}


#ifndef VM_RESERVED
static int via_mm_swapout (struct page *page, struct file *filp)
{
	return 0;
}
#endif /* VM_RESERVED */


static struct vm_operations_struct via_mm_ops = {
	.nopage		= via_mm_nopage,

#ifndef VM_RESERVED
	.swapout	= via_mm_swapout,
#endif
};


static int via_dsp_mmap(struct file *file, struct vm_area_struct *vma)
{
	struct via_info *card;
	int nonblock = (file->f_flags & O_NONBLOCK);
	int rc = -EINVAL, rd=0, wr=0;
	unsigned long max_size, size, start, offset;

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

	DPRINTK ("ENTER, start %lXh, size %ld, pgoff %ld\n",
		 vma->vm_start,
		 vma->vm_end - vma->vm_start,
		 vma->vm_pgoff);

	max_size = 0;
	if (vma->vm_flags & VM_READ) {
		rd = 1;
		via_chan_set_buffering(card, &card->ch_in, -1);
		via_chan_buffer_init (card, &card->ch_in);
		max_size += card->ch_in.page_number << PAGE_SHIFT;
	}
	if (vma->vm_flags & VM_WRITE) {
		wr = 1;
		via_chan_set_buffering(card, &card->ch_out, -1);
		via_chan_buffer_init (card, &card->ch_out);
		max_size += card->ch_out.page_number << PAGE_SHIFT;
	}

	start = vma->vm_start;
	offset = (vma->vm_pgoff << PAGE_SHIFT);
	size = vma->vm_end - vma->vm_start;

	/* some basic size/offset sanity checks */
	if (size > max_size)
		goto out;
	if (offset > max_size - size)
		goto out;

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

	vma->vm_ops = &via_mm_ops;
	vma->vm_private_data = card;

#ifdef VM_RESERVED
	vma->vm_flags |= VM_RESERVED;
#endif

	if (rd)
		card->ch_in.is_mapped = 1;
	if (wr)
		card->ch_out.is_mapped = 1;

	mutex_unlock(&card->syscall_mutex);
	rc = 0;

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


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

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

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

	/* grab current channel software pointer.  In the case of
	 * recording, this is pointing to the next buffer that
	 * will receive data from the audio hardware.
	 */
	n = chan->sw_ptr;

	/* n_frags represents the number of fragments waiting
	 * to be copied to userland.  sleep until at least
	 * one buffer has been read from the audio hardware.
	 */
	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;
		}

		mutex_unlock(&card->syscall_mutex);

		DPRINTK ("Sleeping on block %d\n", n);
		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 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)) * 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 __user *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);
	card = file->private_data;
	assert (card != NULL);

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


static ssize_t via_dsp_do_write (struct via_info *card,
				 const char __user *userbuf, size_t count,
				 int nonblock)
{
        DECLARE_WAITQUEUE(wait, current);
	const char __user *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 (need_resched()) {
		mutex_unlock(&card->syscall_mutex);
		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;
		}

		mutex_unlock(&card->syscall_mutex);

		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 po