dmasound_atari.c

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			bal -= sSpeed;
		}
		expand_data = data;
	}
	expand_bal = bal;
	used -= userCount;
	*frameUsed += usedf-frameLeft;
	return used;
}


static ssize_t ata_ctx_s16be(const u_char *userPtr, size_t userCount,
			     u_char frame[], ssize_t *frameUsed,
			     ssize_t frameLeft)
{
	/* this should help gcc to stuff everything into registers */
	long bal = expand_bal;
	long hSpeed = dmasound.hard.speed, sSpeed = dmasound.soft.speed;
	ssize_t used, usedf;

	used = userCount;
	usedf = frameLeft;
	if (!dmasound.soft.stereo) {
		u_short *p = (u_short *)&frame[*frameUsed];
		u_short data = expand_data;
		while (frameLeft >= 4) {
			if (bal < 0) {
				if (userCount < 2)
					break;
				if (get_user(data, ((u_short *)userPtr)++))
					return -EFAULT;
				userCount -= 2;
				bal += hSpeed;
			}
			*p++ = data;
			*p++ = data;
			frameLeft -= 4;
			bal -= sSpeed;
		}
		expand_data = data;
	} else {
		u_long *p = (u_long *)&frame[*frameUsed];
		u_long data = expand_data;
		while (frameLeft >= 4) {
			if (bal < 0) {
				if (userCount < 4)
					break;
				if (get_user(data, ((u_int *)userPtr)++))
					return -EFAULT;
				userCount -= 4;
				bal += hSpeed;
			}
			*p++ = data;
			frameLeft -= 4;
			bal -= sSpeed;
		}
		expand_data = data;
	}
	expand_bal = bal;
	used -= userCount;
	*frameUsed += usedf-frameLeft;
	return used;
}


static ssize_t ata_ctx_u16be(const u_char *userPtr, size_t userCount,
			     u_char frame[], ssize_t *frameUsed,
			     ssize_t frameLeft)
{
	/* this should help gcc to stuff everything into registers */
	long bal = expand_bal;
	long hSpeed = dmasound.hard.speed, sSpeed = dmasound.soft.speed;
	ssize_t used, usedf;

	used = userCount;
	usedf = frameLeft;
	if (!dmasound.soft.stereo) {
		u_short *p = (u_short *)&frame[*frameUsed];
		u_short data = expand_data;
		while (frameLeft >= 4) {
			if (bal < 0) {
				if (userCount < 2)
					break;
				if (get_user(data, ((u_short *)userPtr)++))
					return -EFAULT;
				data ^= 0x8000;
				userCount -= 2;
				bal += hSpeed;
			}
			*p++ = data;
			*p++ = data;
			frameLeft -= 4;
			bal -= sSpeed;
		}
		expand_data = data;
	} else {
		u_long *p = (u_long *)&frame[*frameUsed];
		u_long data = expand_data;
		while (frameLeft >= 4) {
			if (bal < 0) {
				if (userCount < 4)
					break;
				if (get_user(data, ((u_int *)userPtr)++))
					return -EFAULT;
				data ^= 0x80008000;
				userCount -= 4;
				bal += hSpeed;
			}
			*p++ = data;
			frameLeft -= 4;
			bal -= sSpeed;
		}
		expand_data = data;
	}
	expand_bal = bal;
	used -= userCount;
	*frameUsed += usedf-frameLeft;
	return used;
}


static ssize_t ata_ctx_s16le(const u_char *userPtr, size_t userCount,
			     u_char frame[], ssize_t *frameUsed,
			     ssize_t frameLeft)
{
	/* this should help gcc to stuff everything into registers */
	long bal = expand_bal;
	long hSpeed = dmasound.hard.speed, sSpeed = dmasound.soft.speed;
	ssize_t used, usedf;

	used = userCount;
	usedf = frameLeft;
	if (!dmasound.soft.stereo) {
		u_short *p = (u_short *)&frame[*frameUsed];
		u_short data = expand_data;
		while (frameLeft >= 4) {
			if (bal < 0) {
				if (userCount < 2)
					break;
				if (get_user(data, ((u_short *)userPtr)++))
					return -EFAULT;
				data = le2be16(data);
				userCount -= 2;
				bal += hSpeed;
			}
			*p++ = data;
			*p++ = data;
			frameLeft -= 4;
			bal -= sSpeed;
		}
		expand_data = data;
	} else {
		u_long *p = (u_long *)&frame[*frameUsed];
		u_long data = expand_data;
		while (frameLeft >= 4) {
			if (bal < 0) {
				if (userCount < 4)
					break;
				if (get_user(data, ((u_int *)userPtr)++))
					return -EFAULT;
				data = le2be16dbl(data);
				userCount -= 4;
				bal += hSpeed;
			}
			*p++ = data;
			frameLeft -= 4;
			bal -= sSpeed;
		}
		expand_data = data;
	}
	expand_bal = bal;
	used -= userCount;
	*frameUsed += usedf-frameLeft;
	return used;
}


static ssize_t ata_ctx_u16le(const u_char *userPtr, size_t userCount,
			     u_char frame[], ssize_t *frameUsed,
			     ssize_t frameLeft)
{
	/* this should help gcc to stuff everything into registers */
	long bal = expand_bal;
	long hSpeed = dmasound.hard.speed, sSpeed = dmasound.soft.speed;
	ssize_t used, usedf;

	used = userCount;
	usedf = frameLeft;
	if (!dmasound.soft.stereo) {
		u_short *p = (u_short *)&frame[*frameUsed];
		u_short data = expand_data;
		while (frameLeft >= 4) {
			if (bal < 0) {
				if (userCount < 2)
					break;
				if (get_user(data, ((u_short *)userPtr)++))
					return -EFAULT;
				data = le2be16(data) ^ 0x8000;
				userCount -= 2;
				bal += hSpeed;
			}
			*p++ = data;
			*p++ = data;
			frameLeft -= 4;
			bal -= sSpeed;
		}
		expand_data = data;
	} else {
		u_long *p = (u_long *)&frame[*frameUsed];
		u_long data = expand_data;
		while (frameLeft >= 4) {
			if (bal < 0) {
				if (userCount < 4)
					break;
				if (get_user(data, ((u_int *)userPtr)++))
					return -EFAULT;
				data = le2be16dbl(data) ^ 0x80008000;
				userCount -= 4;
				bal += hSpeed;
			}
			*p++ = data;
			frameLeft -= 4;
			bal -= sSpeed;
		}
		expand_data = data;
	}
	expand_bal = bal;
	used -= userCount;
	*frameUsed += usedf-frameLeft;
	return used;
}


static TRANS transTTNormal = {
	.ct_ulaw	= ata_ct_law,
	.ct_alaw	= ata_ct_law,
	.ct_s8		= ata_ct_s8,
	.ct_u8		= ata_ct_u8,
};

static TRANS transTTExpanding = {
	.ct_ulaw	= ata_ctx_law,
	.ct_alaw	= ata_ctx_law,
	.ct_s8		= ata_ctx_s8,
	.ct_u8		= ata_ctx_u8,
};

static TRANS transFalconNormal = {
	.ct_ulaw	= ata_ct_law,
	.ct_alaw	= ata_ct_law,
	.ct_s8		= ata_ct_s8,
	.ct_u8		= ata_ct_u8,
	.ct_s16be	= ata_ct_s16be,
	.ct_u16be	= ata_ct_u16be,
	.ct_s16le	= ata_ct_s16le,
	.ct_u16le	= ata_ct_u16le
};

static TRANS transFalconExpanding = {
	.ct_ulaw	= ata_ctx_law,
	.ct_alaw	= ata_ctx_law,
	.ct_s8		= ata_ctx_s8,
	.ct_u8		= ata_ctx_u8,
	.ct_s16be	= ata_ctx_s16be,
	.ct_u16be	= ata_ctx_u16be,
	.ct_s16le	= ata_ctx_s16le,
	.ct_u16le	= ata_ctx_u16le,
};


/*** Low level stuff *********************************************************/



/*
 * Atari (TT/Falcon)
 */

static void *AtaAlloc(unsigned int size, int flags)
{
	return atari_stram_alloc(size, "dmasound");
}

static void AtaFree(void *obj, unsigned int size)
{
	atari_stram_free( obj );
}

static int __init AtaIrqInit(void)
{
	/* Set up timer A. Timer A
	   will receive a signal upon end of playing from the sound
	   hardware. Furthermore Timer A is able to count events
	   and will cause an interrupt after a programmed number
	   of events. So all we need to keep the music playing is
	   to provide the sound hardware with new data upon
	   an interrupt from timer A. */
	mfp.tim_ct_a = 0;	/* ++roman: Stop timer before programming! */
	mfp.tim_dt_a = 1;	/* Cause interrupt after first event. */
	mfp.tim_ct_a = 8;	/* Turn on event counting. */
	/* Register interrupt handler. */
	request_irq(IRQ_MFP_TIMA, AtaInterrupt, IRQ_TYPE_SLOW, "DMA sound",
		    AtaInterrupt);
	mfp.int_en_a |= 0x20;	/* Turn interrupt on. */
	mfp.int_mk_a |= 0x20;
	return 1;
}

#ifdef MODULE
static void AtaIrqCleanUp(void)
{
	mfp.tim_ct_a = 0;	/* stop timer */
	mfp.int_en_a &= ~0x20;	/* turn interrupt off */
	free_irq(IRQ_MFP_TIMA, AtaInterrupt);
}
#endif /* MODULE */


#define TONE_VOXWARE_TO_DB(v) \
	(((v) < 0) ? -12 : ((v) > 100) ? 12 : ((v) - 50) * 6 / 25)
#define TONE_DB_TO_VOXWARE(v) (((v) * 25 + ((v) > 0 ? 5 : -5)) / 6 + 50)


static int AtaSetBass(int bass)
{
	dmasound.bass = TONE_VOXWARE_TO_DB(bass);
	atari_microwire_cmd(MW_LM1992_BASS(dmasound.bass));
	return TONE_DB_TO_VOXWARE(dmasound.bass);
}


static int AtaSetTreble(int treble)
{
	dmasound.treble = TONE_VOXWARE_TO_DB(treble);
	atari_microwire_cmd(MW_LM1992_TREBLE(dmasound.treble));
	return TONE_DB_TO_VOXWARE(dmasound.treble);
}



/*
 * TT
 */


static void TTSilence(void)
{
	tt_dmasnd.ctrl = DMASND_CTRL_OFF;
	atari_microwire_cmd(MW_LM1992_PSG_HIGH); /* mix in PSG signal 1:1 */
}


static void TTInit(void)
{
	int mode, i, idx;
	const int freq[4] = {50066, 25033, 12517, 6258};

	/* search a frequency that fits into the allowed error range */

	idx = -1;
	for (i = 0; i < ARRAY_SIZE(freq); i++)
		/* this isn't as much useful for a TT than for a Falcon, but
		 * then it doesn't hurt very much to implement it for a TT too.
		 */
		if ((100 * abs(dmasound.soft.speed - freq[i]) / freq[i]) < catchRadius)
			idx = i;
	if (idx > -1) {
		dmasound.soft.speed = freq[idx];
		dmasound.trans_write = &transTTNormal;
	} else
		dmasound.trans_write = &transTTExpanding;

	TTSilence();
	dmasound.hard = dmasound.soft;

	if (dmasound.hard.speed > 50066) {
		/* we would need to squeeze the sound, but we won't do that */
		dmasound.hard.speed = 50066;
		mode = DMASND_MODE_50KHZ;
		dmasound.trans_write = &transTTNormal;
	} else if (dmasound.hard.speed > 25033) {
		dmasound.hard.speed = 50066;
		mode = DMASND_MODE_50KHZ;
	} else if (dmasound.hard.speed > 12517) {
		dmasound.hard.speed = 25033;
		mode = DMASND_MODE_25KHZ;
	} else if (dmasound.hard.speed > 6258) {
		dmasound.hard.speed = 12517;
		mode = DMASND_MODE_12KHZ;
	} else {
		dmasound.hard.speed = 6258;
		mode = DMASND_MODE_6KHZ;
	}

	tt_dmasnd.mode = (dmasound.hard.stereo ?
			  DMASND_MODE_STEREO : DMASND_MODE_MONO) |
		DMASND_MODE_8BIT | mode;

	expand_bal = -dmasound.soft.speed;
}


static int TTSetFormat(int format)
{
	/* TT sound DMA supports only 8bit modes */

	switch (format) {
	case AFMT_QUERY:
		return dmasound.soft.format;
	case AFMT_MU_LAW:
	case AFMT_A_LAW:
	case AFMT_S8:
	case AFMT_U8:
		break;
	default:
		format = AFMT_S8;
	}

	dmasound.soft.format = format;
	dmasound.soft.size = 8;
	if (dmasound.minDev == SND_DEV_DSP) {
		dmasound.dsp.format = format;
		dmasound.dsp.size = 8;
	}
	TTInit();

	return format;
}


#define VOLUME_VOXWARE_TO_DB(v) \
	(((v) < 0) ? -40 : ((v) > 100) ? 0 : ((v) * 2) / 5 - 40)
#define VOLUME_DB_TO_VOXWARE(v) ((((v) + 40) * 5 + 1) / 2)


static int TTSetVolume(int volume)
{
	dmasound.volume_left = VOLUME_VOXWARE_TO_DB(volume & 0xff);
	atari_microwire_cmd(MW_LM1992_BALLEFT(dmasound.volume_left));
	dmasound.volume_right = VOLUME_VOXWARE_TO_DB((volume & 0xff00) >> 8);
	atari_microwire_cmd(MW_LM1992_BALRIGHT(dmasound.volume_right));
	return VOLUME_DB_TO_VOXWARE(dmasound.volume_left) |
	       (VOLUME_DB_TO_VOXWARE(dmasound.volume_right) << 8);
}


#define GAIN_VOXWARE_TO_DB(v) \
	(((v) < 0) ? -80 : ((v) > 100) ? 0 : ((v) * 4) / 5 - 80)
#define GAIN_DB_TO_VOXWARE(v) ((((v) + 80) * 5 + 1) / 4)

static int TTSetGain(int gain)
{
	dmasound.gain = GAIN_VOXWARE_TO_DB(gain);
	atari_microwire_cmd(MW_LM1992_VOLUME(dmasound.gain));
	return GAIN_DB_TO_VOXWARE(dmasound.gain);
}



/*
 * Falcon
 */


static void FalconSilence(void)
{
	/* stop playback, set sample rate 50kHz for PSG sound */
	tt_dmasnd.ctrl = DMASND_CTRL_OFF;
	tt_dmasnd.mode = DMASND_MODE_50KHZ | DMASND_MODE_STEREO | DMASND_MODE_8BIT;
	tt_dmasnd.int_div = 0; /* STE compatible divider */
	tt_dmasnd.int_ctrl = 0x0;
	tt_dmasnd.cbar_src = 0x0000; /* no matrix inputs */
	tt_dmasnd.cbar_dst = 0x0000; /* no matrix outputs */
	tt_dmasnd.dac_src = 1; /* connect ADC to DAC, disconnect matrix */
	tt_dmasnd.adc_src = 3; /* ADC Input = PSG */
}


static void FalconInit(void)
{
	int divider, i, idx;
	const int freq[8] = {49170, 32780, 24585, 19668, 16390, 12292, 9834, 8195};

	/* search a frequency that fits into the allowed error range */

	idx = -1;
	for (i = 0; i < ARRAY_SIZE(freq); i++)
		/* if we will tolerate 3% error 8000Hz->8195Hz (2.38%) would
		 * be playable without expanding, but that now a kernel runtime
		 * option
		 */
		if ((100 * abs(dmasound.soft.speed - freq[i]) / freq[i]) < catchRadius)
			idx = i;
	if (idx > -1) {
		dmasound.soft.speed = freq[idx];
		dmasound.trans_write = &transFalconNormal;
	} else
		dmasound.trans_write = &transFalconExpanding;

	FalconSilence();
	dmasound.hard = dmasound.soft;

	if (dmasound.hard.size == 16) {
		/* the Falcon can play 16bit samples only in stereo */
		dmasound.hard.stereo = 1;
	}

	if (dmasound.hard.speed > 49170) {
		/* we would need to squeeze the sound, but we won't do that */
		dmasound.hard.speed = 49170;
		divider = 1;
		dmasound.trans_write = &transFalconNormal;
	} else if (dmasound.hard.speed > 32780) {
		dmasound.hard.speed = 49170;
		divider = 1;
	} else if (dmasound.hard.speed > 24585) {
		dmasound.hard.speed = 32780;
		divider = 2;
	} else if (dmasound.hard.speed > 19668) {
		dmasound.hard.speed = 24585;
		divider = 3;
	} else if (dmasound.hard.speed > 16390) {
		dmasound.hard.speed = 19668;
		divider = 4;
	} else if (dmasound.hard.speed > 12292) {
		dmasound.hard.speed = 16390;
		divider = 5;
	} else if (dmasound.hard.speed > 9834) {
		dmasound.hard.speed = 12292;
		divider = 7;
	} else if (dmasound.hard.speed > 8195) {
		dmasound.hard.speed = 9834;
		divider = 9;
	} else {