dmasound_core.c

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	 * will be set so long as the shared resources have no owner.
	 */

	if (shared_resource_owner == 0) {
		dmasound.soft = dmasound.mach.default_soft ;
		dmasound.hard = dmasound.mach.default_hard ;
		dmasound.dsp = dmasound.mach.default_soft ;
		shared_resources_initialised = 0 ;
	}
	return 0 ;
}


    /*
     *  /dev/sndstat
     */

/* we allow more space for record-enabled because there are extra output lines.
   the number here must include the amount we are prepared to give to the low-level
   driver.
*/

#ifdef HAS_RECORD
#define STAT_BUFF_LEN 1024
#else
#define STAT_BUFF_LEN 768
#endif

/* this is how much space we will allow the low-level driver to use
   in the stat buffer.  Currently, 2 * (80 character line + <NL>).
   We do not police this (it is up to the ll driver to be honest).
*/

#define LOW_LEVEL_STAT_ALLOC 162

static struct {
    int busy;
    char buf[STAT_BUFF_LEN];	/* state.buf should not overflow! */
    int len, ptr;
} state;

/* publish this function for use by low-level code, if required */

char *get_afmt_string(int afmt)
{
        switch(afmt) {
            case AFMT_MU_LAW:
                return "mu-law";
                break;
            case AFMT_A_LAW:
                return "A-law";
                break;
            case AFMT_U8:
                return "unsigned 8 bit";
                break;
            case AFMT_S8:
                return "signed 8 bit";
                break;
            case AFMT_S16_BE:
                return "signed 16 bit BE";
                break;
            case AFMT_U16_BE:
                return "unsigned 16 bit BE";
                break;
            case AFMT_S16_LE:
                return "signed 16 bit LE";
                break;
            case AFMT_U16_LE:
                return "unsigned 16 bit LE";
                break;
	    case 0:
		return "format not set" ;
		break ;
            default:
                break ;
        }
        return "ERROR: Unsupported AFMT_XXXX code" ;
}

static int state_open(struct inode *inode, struct file *file)
{
	char *buffer = state.buf;
	int len = 0;

	if (state.busy)
		return -EBUSY;

	if (!try_module_get(dmasound.mach.owner))
		return -ENODEV;
	state.ptr = 0;
	state.busy = 1;

	len += sprintf(buffer+len, "%sDMA sound driver rev %03d :\n",
		dmasound.mach.name, (DMASOUND_CORE_REVISION<<4) +
		((dmasound.mach.version>>8) & 0x0f));
	len += sprintf(buffer+len,
		"Core driver edition %02d.%02d : %s driver edition %02d.%02d\n",
		DMASOUND_CORE_REVISION, DMASOUND_CORE_EDITION, dmasound.mach.name2,
		(dmasound.mach.version >> 8), (dmasound.mach.version & 0xff)) ;

	/* call the low-level module to fill in any stat info. that it has
	   if present.  Maximum buffer usage is specified.
	*/

	if (dmasound.mach.state_info)
		len += dmasound.mach.state_info(buffer+len,
			(size_t) LOW_LEVEL_STAT_ALLOC) ;

	/* make usage of the state buffer as deterministic as poss.
	   exceptional conditions could cause overrun - and this is flagged as
	   a kernel error.
	*/

	/* formats and settings */

	len += sprintf(buffer+len,"\t\t === Formats & settings ===\n") ;
	len += sprintf(buffer+len,"Parameter %20s%20s\n","soft","hard") ;
	len += sprintf(buffer+len,"Format   :%20s%20s\n",
		get_afmt_string(dmasound.soft.format),
		get_afmt_string(dmasound.hard.format));

	len += sprintf(buffer+len,"Samp Rate:%14d s/sec%14d s/sec\n",
		       dmasound.soft.speed, dmasound.hard.speed);

	len += sprintf(buffer+len,"Channels :%20s%20s\n",
		       dmasound.soft.stereo ? "stereo" : "mono",
		       dmasound.hard.stereo ? "stereo" : "mono" );

	/* sound queue status */

	len += sprintf(buffer+len,"\t\t === Sound Queue status ===\n");
	len += sprintf(buffer+len,"Allocated:%8s%6s\n","Buffers","Size") ;
	len += sprintf(buffer+len,"%9s:%8d%6d\n",
		"write", write_sq.numBufs, write_sq.bufSize) ;
#ifdef HAS_RECORD
	if (dmasound.mach.record)
		len += sprintf(buffer+len,"%9s:%8d%6d\n",
			"read", read_sq.numBufs, read_sq.bufSize) ;
#endif
	len += sprintf(buffer+len,
		"Current  : MaxFrg FragSiz MaxAct Frnt Rear "
		"Cnt RrSize A B S L  xruns\n") ;
	len += sprintf(buffer+len,"%9s:%7d%8d%7d%5d%5d%4d%7d%2d%2d%2d%2d%7d\n",
		"write", write_sq.max_count, write_sq.block_size,
		write_sq.max_active, write_sq.front, write_sq.rear,
		write_sq.count, write_sq.rear_size, write_sq.active,
		write_sq.busy, write_sq.syncing, write_sq.locked, write_sq.xruns) ;
#ifdef HAS_RECORD
	if (dmasound.mach.record)
		len += sprintf(buffer+len,"%9s:%7d%8d%7d%5d%5d%4d%7d%2d%2d%2d%2d%7d\n",
			"read", read_sq.max_count, read_sq.block_size,
			read_sq.max_active, read_sq.front, read_sq.rear,
			read_sq.count, read_sq.rear_size, read_sq.active,
			read_sq.busy, read_sq.syncing, read_sq.locked, read_sq.xruns) ;
#endif
#ifdef DEBUG_DMASOUND
printk("dmasound: stat buffer used %d bytes\n", len) ;
#endif

	if (len >= STAT_BUFF_LEN)
		printk(KERN_ERR "dmasound_core: stat buffer overflowed!\n");

	state.len = len;
	return 0;
}

static int state_release(struct inode *inode, struct file *file)
{
	lock_kernel();
	state.busy = 0;
	module_put(dmasound.mach.owner);
	unlock_kernel();
	return 0;
}

static ssize_t state_read(struct file *file, char __user *buf, size_t count,
			  loff_t *ppos)
{
	int n = state.len - state.ptr;
	if (n > count)
		n = count;
	if (n <= 0)
		return 0;
	if (copy_to_user(buf, &state.buf[state.ptr], n))
		return -EFAULT;
	state.ptr += n;
	return n;
}

static struct file_operations state_fops = {
	.owner		= THIS_MODULE,
	.llseek		= no_llseek,
	.read		= state_read,
	.open		= state_open,
	.release	= state_release,
};

static int state_init(void)
{
#ifndef MODULE
	int state_unit;
#endif
	state_unit = register_sound_special(&state_fops, SND_DEV_STATUS);
	if (state_unit < 0)
		return state_unit ;
	state.busy = 0;
	return 0 ;
}


    /*
     *  Config & Setup
     *
     *  This function is called by _one_ chipset-specific driver
     */

int dmasound_init(void)
{
	int res ;
#ifdef MODULE
	if (irq_installed)
		return -EBUSY;
#endif

	/* Set up sound queue, /dev/audio and /dev/dsp. */

	/* Set default settings. */
	if ((res = sq_init()) < 0)
		return res ;

	/* Set up /dev/sndstat. */
	if ((res = state_init()) < 0)
		return res ;

	/* Set up /dev/mixer. */
	mixer_init();

	if (!dmasound.mach.irqinit()) {
		printk(KERN_ERR "DMA sound driver: Interrupt initialization failed\n");
		return -ENODEV;
	}
#ifdef MODULE
	irq_installed = 1;
#endif

	printk(KERN_INFO "%s DMA sound driver rev %03d installed\n",
		dmasound.mach.name, (DMASOUND_CORE_REVISION<<4) +
		((dmasound.mach.version>>8) & 0x0f));
	printk(KERN_INFO
		"Core driver edition %02d.%02d : %s driver edition %02d.%02d\n",
		DMASOUND_CORE_REVISION, DMASOUND_CORE_EDITION, dmasound.mach.name2,
		(dmasound.mach.version >> 8), (dmasound.mach.version & 0xff)) ;
	printk(KERN_INFO "Write will use %4d fragments of %7d bytes as default\n",
		numWriteBufs, writeBufSize) ;
#ifdef HAS_RECORD
	if (dmasound.mach.record)
		printk(KERN_INFO
			"Read  will use %4d fragments of %7d bytes as default\n",
			numReadBufs, readBufSize) ;
#endif

	return 0;
}

#ifdef MODULE

void dmasound_deinit(void)
{
	if (irq_installed) {
		sound_silence();
		dmasound.mach.irqcleanup();
		irq_installed = 0;
	}

	write_sq_release_buffers();
	read_sq_release_buffers();

	if (mixer_unit >= 0)
		unregister_sound_mixer(mixer_unit);
	if (state_unit >= 0)
		unregister_sound_special(state_unit);
	if (sq_unit >= 0)
		unregister_sound_dsp(sq_unit);
}

#else /* !MODULE */

static int dmasound_setup(char *str)
{
	int ints[6], size;

	str = get_options(str, ARRAY_SIZE(ints), ints);

	/* check the bootstrap parameter for "dmasound=" */

	/* FIXME: other than in the most naive of cases there is no sense in these
	 *	  buffers being other than powers of two.  This is not checked yet.
	 */

	switch (ints[0]) {
#ifdef HAS_RECORD
        case 5:
                if ((ints[5] < 0) || (ints[5] > MAX_CATCH_RADIUS))
                        printk("dmasound_setup: invalid catch radius, using default = %d\n", catchRadius);
                else
                        catchRadius = ints[5];
                /* fall through */
        case 4:
                if (ints[4] < MIN_BUFFERS)
                        printk("dmasound_setup: invalid number of read buffers, using default = %d\n",
                                 numReadBufs);
                else
                        numReadBufs = ints[4];
                /* fall through */
        case 3:
		if ((size = ints[3]) < 256)  /* check for small buffer specs */
			size <<= 10 ;
                if (size < MIN_BUFSIZE || size > MAX_BUFSIZE)
                        printk("dmasound_setup: invalid read buffer size, using default = %d\n", readBufSize);
                else
                        readBufSize = size;
                /* fall through */
#else
	case 3:
		if ((ints[3] < 0) || (ints[3] > MAX_CATCH_RADIUS))
			printk("dmasound_setup: invalid catch radius, using default = %d\n", catchRadius);
		else
			catchRadius = ints[3];
		/* fall through */
#endif
	case 2:
		if (ints[1] < MIN_BUFFERS)
			printk("dmasound_setup: invalid number of buffers, using default = %d\n", numWriteBufs);
		else
			numWriteBufs = ints[1];
		/* fall through */
	case 1:
		if ((size = ints[2]) < 256) /* check for small buffer specs */
			size <<= 10 ;
                if (size < MIN_BUFSIZE || size > MAX_BUFSIZE)
                        printk("dmasound_setup: invalid write buffer size, using default = %d\n", writeBufSize);
                else
                        writeBufSize = size;
	case 0:
		break;
	default:
		printk("dmasound_setup: invalid number of arguments\n");
		return 0;
	}
	return 1;
}

__setup("dmasound=", dmasound_setup);

#endif /* !MODULE */

    /*
     *  Conversion tables
     */

#ifdef HAS_8BIT_TABLES
/* 8 bit mu-law */

char dmasound_ulaw2dma8[] = {
	-126,	-122,	-118,	-114,	-110,	-106,	-102,	-98,
	-94,	-90,	-86,	-82,	-78,	-74,	-70,	-66,
	-63,	-61,	-59,	-57,	-55,	-53,	-51,	-49,
	-47,	-45,	-43,	-41,	-39,	-37,	-35,	-33,
	-31,	-30,	-29,	-28,	-27,	-26,	-25,	-24,
	-23,	-22,	-21,	-20,	-19,	-18,	-17,	-16,
	-16,	-15,	-15,	-14,	-14,	-13,	-13,	-12,
	-12,	-11,	-11,	-10,	-10,	-9,	-9,	-8,
	-8,	-8,	-7,	-7,	-7,	-7,	-6,	-6,
	-6,	-6,	-5,	-5,	-5,	-5,	-4,	-4,
	-4,	-4,	-4,	-4,	-3,	-3,	-3,	-3,
	-3,	-3,	-3,	-3,	-2,	-2,	-2,	-2,
	-2,	-2,	-2,	-2,	-2,	-2,	-2,	-2,
	-1,	-1,	-1,	-1,	-1,	-1,	-1,	-1,
	-1,	-1,	-1,	-1,	-1,	-1,	-1,	-1,
	-1,	-1,	-1,	-1,	-1,	-1,	-1,	0,
	125,	121,	117,	113,	109,	105,	101,	97,
	93,	89,	85,	81,	77,	73,	69,	65,
	62,	60,	58,	56,	54,	52,	50,	48,
	46,	44,	42,	40,	38,	36,	34,	32,
	30,	29,	28,	27,	26,	25,	24,	23,
	22,	21,	20,	19,	18,	17,	16,	15,
	15,	14,	14,	13,	13,	12,	12,	11,
	11,	10,	10,	9,	9,	8,	8,	7,
	7,	7,	6,	6,	6,	6,	5,	5,
	5,	5,	4,	4,	4,	4,	3,	3,
	3,	3,	3,	3,	2,	2,	2,	2,
	2,	2,	2,	2,	1,	1,	1,	1,
	1,	1,	1,	1,	1,	1,	1,	1,
	0,	0,	0,	0,	0,	0,	0,	0,
	0,	0,	0,	0,	0,	0,	0,	0,
	0,	0,	0,	0,	0,	0,	0,	0
};

/* 8 bit A-law */

char dmasound_alaw2dma8[] = {
	-22,	-21,	-24,	-23,	-18,	-17,	-20,	-19,
	-30,	-29,	-32,	-31,	-26,	-25,	-28,	-27,
	-11,	-11,	-12,	-12,	-9,	-9,	-10,	-10,
	-15,	-15,	-16,	-16,	-13,	-13,	-14,	-14,
	-86,	-82,	-94,	-90,	-70,	-66,	-78,	-74,
	-118,	-114,	-126,	-122,	-102,	-98,	-110,	-106,
	-43,	-41,	-47,	-45,	-35,	-33,	-39,	-37,
	-59,	-57,	-63,	-61,	-51,	-49,	-55,	-53,
	-2,	-2,	-2,	-2,	-2,	-2,	-2,	-2,
	-2,	-2,	-2,	-2,	-2,	-2,	-2,	-2,
	-1,	-1,	-1,	-1,	-1,	-1,	-1,	-1,
	-1,	-1,	-1,	-1,	-1,	-1,	-1,	-1,
	-6,	-6,	-6,	-6,	-5,	-5,	-5,	-5,
	-8,	-8,	-8,	-8,	-7,	-7,	-7,	-7,
	-3,	-3,	-3,	-3,	-3,	-3,	-3,	-3,
	-4,	-4,	-4,	-4,	-4,	-4,	-4,	-4,
	21,	20,	23,	22,	17,	16,	19,	18,
	29,	28,	31,	30,	25,	24,	27,	26,
	10,	10,	11,	11,	8,	8,	9,	9,
	14,	14,	15,	15,	12,	12,	13,	13,
	86,	82,	94,	90,	70,	66,	78,	74,
	118,	114,	126,	122,	102,	98,	110,	106,
	43,	41,	47,	45,	35,	33,	39,	37,
	59,	57,	63,	61,	51,	49,	55,	53,
	1,	1,	1,	1,	1,	1,	1,	1,
	1,	1,	1,	1,	1,	1,	1,	1,
	0,	0,	0,	0,	0,	0,	0,	0,
	0,	0,	0,	0,	0,	0,	0,	0,
	5,	5,	5,	5,	4,	4,	4,	4,
	7,	7,	7,	7,	6,	6,	6,	6,
	2,	2,	2,	2,	2,	2,	2,	2,
	3,	3,	3,	3,	3,	3,	3,	3
};
#endif /* HAS_8BIT_TABLES */

    /*
     *  Visible symbols for modules
     */

EXPORT_SYMBOL(dmasound);
EXPORT_SYMBOL(dmasound_init);
#ifdef MODULE
EXPORT_SYMBOL(dmasound_deinit);
#endif
EXPORT_SYMBOL(dmasound_write_sq);
#ifdef HAS_RECORD
EXPORT_SYMBOL(dmasound_read_sq);
#endif
EXPORT_SYMBOL(dmasound_catchRadius);
#ifdef HAS_8BIT_TABLES
EXPORT_SYMBOL(dmasound_ulaw2dma8);
EXPORT_SYMBOL(dmasound_alaw2dma8);
#endif
EXPORT_SYMBOL(get_afmt_string) ;