s3c2410-uda1341.c

这是一个适用于三星公司S3C2410的音频驱动程序

		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;
				break;
                }
        }


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

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

	DPRINTK("audio_poll() returned mask of %s\n",
		(mask & POLLOUT) ? "w" : "");

	return mask;
}


static loff_t smdk2410_audio_llseek(struct file *file, loff_t offset, 
				    int origin)
{
            return -ESPIPE;
}


static int smdk2410_mixer_ioctl(struct inode *inode, struct file *file, 
                                unsigned int cmd, unsigned long arg)
{
        int ret;
        long val = 0;

	switch (cmd) {
		case SOUND_MIXER_INFO:
		{
			mixer_info info;
			strncpy(info.id, "UDA1341", sizeof(info.id));
			strncpy(info.name,"Philips UDA1341", sizeof(info.name));
			info.modify_counter = audio_mix_modcnt;
			return copy_to_user((void *)arg, &info, sizeof(info));
		}
	
		case SOUND_OLD_MIXER_INFO:
		{
			_old_mixer_info info;
			strncpy(info.id, "UDA1341", sizeof(info.id));
			strncpy(info.name,"Philips UDA1341", sizeof(info.name));
			return copy_to_user((void *)arg, &info, sizeof(info));
		}

		case SOUND_MIXER_READ_STEREODEVS:
			return put_user(0, (long *) arg);

		case SOUND_MIXER_READ_CAPS:
			val = SOUND_CAP_EXCL_INPUT;
			return put_user(val, (long *) arg);

		case SOUND_MIXER_WRITE_VOLUME:
			ret = get_user(val, (long *) arg);
			if (ret)
				return ret;
			uda1341_volume = 63 - (((val & 0xff) + 1) * 63) / 100;
			uda1341_l3_address(UDA1341_REG_DATA0);
			uda1341_l3_data(uda1341_volume);
			break;
		
		case SOUND_MIXER_READ_VOLUME:
			val = ((63 - uda1341_volume) * 100) / 63;
			val |= val << 8;
			return put_user(val, (long *) arg);
	
		case SOUND_MIXER_READ_IGAIN:
			val = ((31- mixer_igain) * 100) / 31;
			return put_user(val, (int *) arg);

		case SOUND_MIXER_WRITE_IGAIN:
			ret = get_user(val, (int *) arg);
			if (ret)
				return ret;
			mixer_igain = 31 - (val * 31 / 100);		
			/* use mixer gain channel 1*/
			uda1341_l3_address(UDA1341_REG_DATA0);
			uda1341_l3_data(EXTADDR(EXT0));
			uda1341_l3_data(EXTDATA(EXT0_CH1_GAIN(mixer_igain)));			
			break;

		default:
			DPRINTK("mixer ioctl %u unknown\n", cmd);
			return -ENOSYS;
	}			

	audio_mix_modcnt++;
	return 0;
}

static inline unsigned long cal_bus_clk(unsigned long cpu_clk, unsigned long ratio, int who)
{
	if (!who) {	/* PCLK */
		switch (ratio) {
			case 0:
				return (cpu_clk);
			case 1:
			case 2:
				return (cpu_clk/2);
			case 3:
				return (cpu_clk/4);
			default:
				return 0;
		}
	} else {	/* HCLK */
		switch (ratio) {
			case 0:
			case 1:
				return (cpu_clk);
			case 2:
			case 3:
				return (cpu_clk/2);
			default:
				return 0;
		}
	}
}


/*
 * cpu clock = (((mdiv + 8) * FIN) / ((pdiv + 2) * (1 << sdiv)))
 *  FIN = Input Frequency (to CPU)
 */
unsigned long s3c2410_get_cpu_clk(void)
{
	unsigned long val= __raw_readl(S3C2410_MPLLCON);
	
	return (((GET_MDIV(val) + 8) * FIN_NEW) / \
		((GET_PDIV(val) + 2) * (1 << GET_SDIV(val))));
}

unsigned long s3c2410_get_bus_clk(int who)
{
	unsigned long cpu_clk = s3c2410_get_cpu_clk();
	unsigned long ratio=__raw_readl(S3C2410_CLKDIVN);
	return (cal_bus_clk(cpu_clk, ratio, who));
}
static int iispsr_value(int s_bit_clock, int sample_rate)
{
        int i, prescaler = 0;
        unsigned long tmpval;
        unsigned long tmpval384;
        unsigned long tmpval384min = 0xffff;
 	
	tmpval384 = s3c2410_get_bus_clk(GET_PCLK_NEW) / s_bit_clock;

        for (i = 0; i < 32; i++) {
                tmpval = tmpval384/(i+1);
                if (PCM_ABS((sample_rate - tmpval)) < tmpval384min) {
                        tmpval384min = PCM_ABS((sample_rate - tmpval));
                        prescaler = i;
                }
        }

        DPRINTK("prescaler = %d\n", prescaler);

        return prescaler;
}

static long audio_set_dsp_speed(long val)
{
	switch (val) {
		case 48000:
		case 44100:
	 __raw_writel((IISPSR_A(iispsr_value(S_CLOCK_FREQ, 44100)) \
			| IISPSR_B(iispsr_value(S_CLOCK_FREQ, 44100))),S3C2410_SBC_IISPSR);
			break;
		case 22050:
	__raw_writel((IISPSR_A(iispsr_value(S_CLOCK_FREQ, 22050)) \
				| IISPSR_B(iispsr_value(S_CLOCK_FREQ, 22050))),S3C2410_SBC_IISPSR);
			break;
		case 11025:
	__raw_writel((IISPSR_A(iispsr_value(S_CLOCK_FREQ, 11025)) \
				| IISPSR_B(iispsr_value(S_CLOCK_FREQ, 11025))),S3C2410_SBC_IISPSR);
			break;
		case 8000:
	 __raw_writel( (IISPSR_A(iispsr_value(S_CLOCK_FREQ, 8000)) \
				| IISPSR_B(iispsr_value(S_CLOCK_FREQ, 8000))),S3C2410_SBC_IISPSR);
			break;
		default:
			return -1;
	}

	audio_rate = val;
	
	return audio_rate;
}

static int smdk2410_audio_ioctl(struct inode *inode, struct file *file, 
                                uint cmd, ulong arg)
{
	long val;

	switch (cmd) {
	  	case SNDCTL_DSP_SETFMT:
			get_user(val, (long *) arg);
		  	if (val & AUDIO_FMT_MASK) {
			    	audio_fmt = val;
			    	break;
		  	} else
				return -EINVAL;

	  	case SNDCTL_DSP_CHANNELS:
	  	case SNDCTL_DSP_STEREO:
		  	get_user(val, (long *) arg);
		  	if (cmd == SNDCTL_DSP_STEREO)
			  	val = val ? 2 : 1;
		  	if (val != 1 && val != 2)
			  	return -EINVAL;
		  	audio_channels = val;
		  	break;