s3c2410-uda1341.c

2410开发板上的声卡驱动！网上收集！很全的啊！1341型号

static void uda1341_l3_data(u8 data)
{
	int i;
	unsigned long flags;

	local_irq_save(flags);

	/*
	 * To set Bit 2 of GPBDAT to be 1(GPIO_L3MODE=0x0101010)
	 */ 
	s3c2410_gpio_setpin(S3C2410_GPB2,1);
	udelay(1);
	/*
	 * To set Bit 2 of GPBDAT to be 0(GPIO_L3MODE=0x01010102)
	 */ 
	s3c2410_gpio_setpin(S3C2410_GPB2,0);
	udelay(1);
	/*
	 * To set Bit 2 of GPBDAT to be 1(GPIO_L3MODE=0x01010102)
	 */ 
	s3c2410_gpio_setpin(S3C2410_GPB2,1);
	for (i = 0; i < 8; i++) {
		if (data & 0x1) {
			/*
			 * To set Bit 4 of GPBDAT to be 0(GPIO_L3CLOCK=0x01010104)
			 */
			s3c2410_gpio_setpin(S3C2410_GPB4,0);
			udelay(1);
			/*
			 * To set Bit 3 of GPBDAT to be 1(GPIO_L3DATA=0x01010103)
			 */ 
			s3c2410_gpio_setpin(S3C2410_GPB3,1);
			udelay(1);
			/*
			 * To set Bit 4 of GPBDAT to be 1(GPIO_L3CLOCK=0x01010104)
			 */ 
			s3c2410_gpio_setpin(S3C2410_GPB4,1);
			udelay(1);
		} else {
			/*
			 * To set Bit 4 of GPBDAT to be 0(GPIO_L3CLOCK=0x01010104)
			 */ 
			s3c2410_gpio_setpin(S3C2410_GPB4,0);
			udelay(1);
			/*
			 * To set Bit 3 of GPBDAT to be 0(GPIO_L3DATA=0x01010103)
			 */ 
			s3c2410_gpio_setpin(S3C2410_GPB3,0);
			udelay(1);
			/*
			 * To set Bit 4 of GPBDAT to be 1(GPIO_L3CLOCK=0x01010104)
			 */ 
			s3c2410_gpio_setpin(S3C2410_GPB4,1);
			udelay(1);
		}

		data >>= 1;
	}

	/*
	 * To set Bit 2 of GPBDAT to be 1(GPIO_L3MODE=0x01010102)
	 */ 
	s3c2410_gpio_setpin(S3C2410_GPB2,1);
	/*
	 * To set Bit 2 of GPBDAT to be 0(GPIO_L3MODE=0x01010102)
	 */ 
	s3c2410_gpio_setpin(S3C2410_GPB2,0);
	udelay(1);
	/*
	 * To set Bit 2 of GPBDAT to be 1(GPIO_L3MODE=0x01010102)
	 */ 
	s3c2410_gpio_setpin(S3C2410_GPB2,1);
	local_irq_restore(flags);
}

static void audio_clear_buf(audio_stream_t * s)
{
    	DPRINTK("audio_clear_buf\n");

	s3c2410_dma_ctrl(s->dma_ch, S3C2410_DMAOP_FLUSH);
	if (s->buffers) {
		int frag;

		for (frag = 0; frag < s->nbfrags; frag++) {
			if (!s->buffers[frag].master)
				continue;
			/* To free the dma buffer */ 
			dma_free_coherent(NULL,s->buffers[frag].master,s->buffers[frag].start ,s->buffers[frag].dma_addr);
		}
		kfree(s->buffers);
		s->buffers = NULL;
	}

	s->buf_idx = 0;
	s->buf = NULL;
}

static int audio_setup_buf(audio_stream_t * s)
{
	int frag;
	int dmasize = 0;
	char *dmabuf = 0;
	dma_addr_t dmaphys = 0;

	if (s->buffers)
	{
		return -EBUSY;
	}

	s->nbfrags = audio_nbfrags;
	s->fragsize = audio_fragsize;

	s->buffers = (audio_buf_t *)
	    kmalloc(sizeof(audio_buf_t) * s->nbfrags, GFP_KERNEL);
	if (!s->buffers)
		goto err;
	memset(s->buffers, 0, sizeof(audio_buf_t) * s->nbfrags);

	for (frag = 0; frag < s->nbfrags; frag++) {
		audio_buf_t *b = &s->buffers[frag];

		if (!dmasize) {
			dmasize = (s->nbfrags - frag) * s->fragsize;
			do {
				/*
				 * To allocate the coherent address buffer for dma transfer
				 */ 
				dmabuf=dma_alloc_coherent(NULL,dmasize,&dmaphys,GFP_KERNEL|GFP_DMA);  
				if (!dmabuf) 
				    	dmasize -= s->fragsize;
			} while (!dmabuf && dmasize);
			if (!dmabuf)
				goto err;
			b->master = dmasize;
		}

		b->start = dmabuf;
		b->dma_addr = dmaphys;
		sema_init(&b->sem, 1);
		DPRINTK("buf %d: start %p dma %d\n", frag, b->start, b->dma_addr);
	
		dmabuf += s->fragsize;
		dmaphys += s->fragsize;
		dmasize -= s->fragsize;
	}

	s->buf_idx = 0;
	s->buf = &s->buffers[0];
	return 0;

      err:
	printk(AUDIO_NAME ": unable to allocate audio memory\n ");
	audio_clear_buf(s);
	return -ENOMEM;
}
static void audio_dmaout_done_callback(s3c2410_dma_chan_t  *r_value,void *buf_id, int size,s3c2410_dma_buffresult_t result)
{
	audio_buf_t *b = (audio_buf_t *) buf_id;
	
	up(&b->sem);
	wake_up(&b->sem.wait);
}

static void audio_dmain_done_callback(s3c2410_dma_chan_t  *r_value,void *buf_id, int size,s3c2410_dma_buffresult_t result)
{
	audio_buf_t *b = (audio_buf_t *) buf_id;
	
  	b->size = size;
	up(&b->sem);
	wake_up(&b->sem.wait);		
}
 /* using when write */
static int audio_sync(struct file *file)
{
	audio_stream_t *s = &output_stream;
	audio_buf_t *b = s->buf;

	DPRINTK("audio_sync\n");

	if (!s->buffers)
		return 0;

	if (b->size != 0) {
		down(&b->sem);
		/* To enqueue the dma task */ 
		s3c2410_dma_enqueue(s->dma_ch,(void *)b,b->dma_addr,b->size);
		b->size = 0;
		NEXT_BUF(s, buf);
	}

	b = s->buffers + ((s->nbfrags + s->buf_idx - 1) % s->nbfrags);
	if (down_interruptible(&b->sem))
		return -EINTR;
	up(&b->sem);

	return 0;
}

static inline int copy_from_user_mono_stereo(char *to, const char *from, int count)
{
	u_int *dst = (u_int *)to;
	const char *end = from + count;

	if (verify_area(VERIFY_READ, from, count))
		return -EFAULT;

	if ((int)from & 0x2) {
		u_int v;
		__get_user(v, (const u_short *)from); from += 2;
		*dst++ = v | (v << 16);
	}

	while (from < end-2) {
		u_int v, x, y;
		__get_user(v, (const u_int *)from); from += 4;
		x = v << 16;
		x |= x >> 16;
		y = v >> 16;
		y |= y << 16;
		*dst++ = x;
		*dst++ = y;
	}

	if (from < end) {
		u_int v;
		__get_user(v, (const u_short *)from);
		*dst = v | (v << 16);
	}

	return 0;
}


static ssize_t smdk2410_audio_write(struct file *file, const char *buffer, 
				    size_t count, loff_t * ppos)
{
	const char *buffer0 = buffer;
	audio_stream_t *s = &output_stream;
	int chunksize, ret = 0;
	DPRINTK("audio_write : start count=%d\n", count);
	switch (file->f_flags & O_ACCMODE) {
	  	case O_WRONLY:
	  	case O_RDWR:
			break;
	  	default:
		  	return -EPERM;
	}

	if (!s->buffers && audio_setup_buf(s))
		return -ENOMEM;

	count &= ~0x03;
	while (count > 0) {
		audio_buf_t *b = s->buf;

		if (file->f_flags & O_NONBLOCK) {
			ret = -EAGAIN;
			if (down_trylock(&b->sem))
				break;
		} else {
			ret = -ERESTARTSYS;
			if (down_interruptible(&b->sem))
				break;
		}

		if (audio_channels == 2) {
			chunksize = s->fragsize - b->size;
			if (chunksize > count)
				chunksize = count;
			DPRINTK("write %d to %d\n", chunksize, s->buf_idx);
			if (copy_from_user(b->start + b->size, buffer, chunksize)) {
				up(&b->sem);
				return -EFAULT;
			}
			b->size += chunksize;
		} else {
			chunksize = (s->fragsize - b->size) >> 1;

			if (chunksize > count)
				chunksize = count;
			DPRINTK("write %d to %d\n", chunksize*2, s->buf_idx);
			if (copy_from_user_mono_stereo(b->start + b->size, 
				    		       buffer, chunksize)) {
				up(&b->sem);
				return -EFAULT;
			}

			b->size += chunksize*2;
		}

		buffer += chunksize;
		count -= chunksize;
		if (b->size < s->fragsize) {
			up(&b->sem);
			break;
		}
		/* To enqueue the dma task */ 
		s3c2410_dma_enqueue(s->dma_ch,(void *)b,b->dma_addr,b->size);
		b->size = 0;
		NEXT_BUF(s, buf);
	}

	if ((buffer - buffer0))
		ret = buffer - buffer0;

	DPRINTK("audio_write : end count=%d\n\n", ret);

	return ret;
}


static ssize_t smdk2410_audio_read(struct file *file, char *buffer, 
                                        size_t count, loff_t * ppos)
{
	const char *buffer0 = buffer;
        audio_stream_t *s = &input_stream; 
        int chunksize, ret = 0;
        DPRINTK("audio_read: count=%d\n", count);
	
	if (!s->buffers) {
		int i;
                 if (audio_setup_buf(s))
                         return -ENOMEM;
		 			
                 for (i = 0; i < s->nbfrags; i++) {
                         audio_buf_t *b = s->buf; 
			 down(&b->sem); 
			 s3c2410_dma_enqueue(s->dma_ch,(void *)b,b->dma_addr,s -> fragsize);
                         NEXT_BUF(s, buf);
                 }
         }
        while (count > 0) {
		audio_buf_t *b = s->buf;
                
		/* Wait for a buffer to become full */
                if (file->f_flags & O_NONBLOCK) {
                        ret = -EAGAIN;
                        if (down_trylock(&b->sem)){
                                break;
			}
                } else {
                        ret = -ERESTARTSYS;
                        if (down_interruptible(&b->sem))
			{
                                break;
			}
                }
		chunksize = b->size;
		if (chunksize > count)
                        chunksize = count;
                DPRINTK("read %d from %d\n", chunksize, s->buf_idx);
		if (copy_to_user(buffer, b->start + s->fragsize - b->size,
				       	chunksize)) {
                        up(&b->sem);
                        return -EFAULT;
                }
		
                b->size -= chunksize;
		
                buffer += chunksize;
                count -= chunksize;
                if (b->size > 0) {
                        up(&b->sem);
                        break;
                }
		
		/* Make current buffer available for DMA again */
		s3c2410_dma_enqueue(s->dma_ch,(void *)b,b->dma_addr,s->fragsize);
                
		NEXT_BUF(s, buf);
        }
	
        if ((buffer - buffer0))
                ret = buffer - buffer0;
        DPRINTK("audio_read: return=%d\n", ret);
        return ret;
}


static unsigned int smdk2410_audio_poll(struct file *file, 
					struct poll_table_struct *wait)
{
	unsigned int mask = 0;
	int i;

	DPRINTK("audio_poll(): mode=%s\n",
		(file->f_mode & FMODE_WRITE) ? "w" : "");

	if (file->f_mode & FMODE_READ) {
                if (!input_stream.buffers && audio_setup_buf(&input_stream))
                        return -ENOMEM;
                poll_wait(file, &input_stream.buf->sem.wait, wait);

                for (i = 0; i < input_stream.nbfrags; i++) {
                        if (atomic_read(&input_stream.buffers[i].sem.count) > 0)
                                mask |= POLLIN | POLLWRNORM;