gus_wave.c

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		for (voice = 0; voice < gus_audio_channels; voice++)
		{
			save_flags(flags);
			cli();
			gus_select_voice(voice);
			gus_rampoff();
			gus_voice_volume(1530 + (25 * gus_pcm_volume));
			gus_ramp_range(65, 1530 + (25 * gus_pcm_volume));
			restore_flags(flags);
		}
}

static void play_next_pcm_block(void)
{
	unsigned long flags;
	int speed = gus_audio_speed;
	int this_one, is16bits, chn;
	unsigned long dram_loc;
	unsigned char mode[2], ramp_mode[2];

	if (!pcm_qlen)
		return;

	this_one = pcm_head;

	for (chn = 0; chn < gus_audio_channels; chn++)
	{
		mode[chn] = 0x00;
		ramp_mode[chn] = 0x03;	/* Ramping and rollover off */

		if (chn == 0)
		{
			mode[chn] |= 0x20;	/* Loop IRQ */
			voices[chn].loop_irq_mode = LMODE_PCM;
		}
		if (gus_audio_bits != 8)
		{
			is16bits = 1;
			mode[chn] |= 0x04;	/* 16 bit data */
		}
		else
			is16bits = 0;

		dram_loc = this_one * pcm_bsize;
		dram_loc += chn * pcm_banksize;

		if (this_one == (pcm_nblk - 1))	/* Last fragment of the DRAM buffer */
		{
			mode[chn] |= 0x08;	/* Enable loop */
			ramp_mode[chn] = 0x03;	/* Disable rollover bit */
		}
		else
		{
			if (chn == 0)
				ramp_mode[chn] = 0x04;	/* Enable rollover bit */
		}
		save_flags(flags);
		cli();
		gus_select_voice(chn);
		gus_voice_freq(speed);

		if (gus_audio_channels == 1)
			gus_voice_balance(7);		/* mono */
		else if (chn == 0)
			gus_voice_balance(0);		/* left */
		else
			gus_voice_balance(15);		/* right */

		if (!pcm_active)	/* Playback not already active */
		{
			/*
			 * The playback was not started yet (or there has been a pause).
			 * Start the voice (again) and ask for a rollover irq at the end of
			 * this_one block. If this_one one is last of the buffers, use just
			 * the normal loop with irq.
			 */

			gus_voice_off();
			gus_rampoff();
			gus_voice_volume(1530 + (25 * gus_pcm_volume));
			gus_ramp_range(65, 1530 + (25 * gus_pcm_volume));

			gus_write_addr(0x0a, chn * pcm_banksize, 0, is16bits);	/* Starting position */
			gus_write_addr(0x02, chn * pcm_banksize, 0, is16bits);	/* Loop start */

			if (chn != 0)
				gus_write_addr(0x04, pcm_banksize + (pcm_bsize * pcm_nblk) - 1,
						   0, is16bits);	/* Loop end location */
		}
		if (chn == 0)
			gus_write_addr(0x04, dram_loc + pcm_bsize - 1,
					 0, is16bits);	/* Loop end location */
		else
			mode[chn] |= 0x08;	/* Enable looping */
		restore_flags(flags);
	}
	for (chn = 0; chn < gus_audio_channels; chn++)
	{
		save_flags(flags);
		cli();
		gus_select_voice(chn);
		gus_write8(0x0d, ramp_mode[chn]);
		if (iw_mode)
			gus_write8(0x15, 0x00);	/* Reset voice deactivate bit of SMSI */
		gus_voice_on(mode[chn]);
		restore_flags(flags);
	}
	pcm_active = 1;
}

static void gus_transfer_output_block(int dev, unsigned long buf,
			  int total_count, int intrflag, int chn)
{
	/*
	 * This routine transfers one block of audio data to the DRAM. In mono mode
	 * it's called just once. When in stereo mode, this_one routine is called
	 * once for both channels.
	 *
	 * The left/mono channel data is transferred to the beginning of dram and the
	 * right data to the area pointed by gus_page_size.
	 */

	int this_one, count;
	unsigned long flags;
	unsigned char dma_command;
	unsigned long address, hold_address;

	save_flags(flags);
	cli();

	count = total_count / gus_audio_channels;

	if (chn == 0)
	{
		if (pcm_qlen >= pcm_nblk)
			printk(KERN_WARNING "GUS Warning: PCM buffers out of sync\n");

		this_one = pcm_current_block = pcm_tail;
		pcm_qlen++;
		pcm_tail = (pcm_tail + 1) % pcm_nblk;
		pcm_datasize[this_one] = count;
	}
	else
		this_one = pcm_current_block;

	gus_write8(0x41, 0);	/* Disable GF1 DMA */
	DMAbuf_start_dma(dev, buf + (chn * count), count, DMA_MODE_WRITE);

	address = this_one * pcm_bsize;
	address += chn * pcm_banksize;

	if (audio_devs[dev]->dmap_out->dma > 3)
	{
		hold_address = address;
		address = address >> 1;
		address &= 0x0001ffffL;
		address |= (hold_address & 0x000c0000L);
	}
	gus_write16(0x42, (address >> 4) & 0xffff);	/* DRAM DMA address */

	dma_command = 0x21;	/* IRQ enable, DMA start */

	if (gus_audio_bits != 8)
		dma_command |= 0x40;	/* 16 bit _DATA_ */
	else
		dma_command |= 0x80;	/* Invert MSB */

	if (audio_devs[dev]->dmap_out->dma > 3)
		dma_command |= 0x04;	/* 16 bit DMA channel */

	gus_write8(0x41, dma_command);	/* Kick start */

	if (chn == (gus_audio_channels - 1))	/* Last channel */
	{
		/*
		 * Last (right or mono) channel data
		 */
		dma_active = 1;	/* DMA started. There is a unacknowledged buffer */
		active_device = GUS_DEV_PCM_DONE;
		if (!pcm_active && (pcm_qlen > 1 || count < pcm_bsize))
		{
			play_next_pcm_block();
		}
	}
	else
	{
		/*
		 * Left channel data. The right channel
		 * is transferred after DMA interrupt
		 */
		active_device = GUS_DEV_PCM_CONTINUE;
	}

	restore_flags(flags);
}

static void gus_uninterleave8(char *buf, int l)
{
/* This routine uninterleaves 8 bit stereo output (LRLRLR->LLLRRR) */
	int i, p = 0, halfsize = l / 2;
	char *buf2 = buf + halfsize, *src = bounce_buf;

	memcpy(bounce_buf, buf, l);

	for (i = 0; i < halfsize; i++)
	{
		buf[i] = src[p++];	/* Left channel */
		buf2[i] = src[p++];	/* Right channel */
	}
}

static void gus_uninterleave16(short *buf, int l)
{
/* This routine uninterleaves 16 bit stereo output (LRLRLR->LLLRRR) */
	int i, p = 0, halfsize = l / 2;
	short *buf2 = buf + halfsize, *src = (short *) bounce_buf;

	memcpy(bounce_buf, (char *) buf, l * 2);

	for (i = 0; i < halfsize; i++)
	{
		buf[i] = src[p++];	/* Left channel */
		buf2[i] = src[p++];	/* Right channel */
	}
}

static void gus_audio_output_block(int dev, unsigned long buf, int total_count,
		       int intrflag)
{
	struct dma_buffparms *dmap = audio_devs[dev]->dmap_out;

	dmap->flags |= DMA_NODMA | DMA_NOTIMEOUT;

	pcm_current_buf = buf;
	pcm_current_count = total_count;
	pcm_current_intrflag = intrflag;
	pcm_current_dev = dev;
	if (gus_audio_channels == 2)
	{
		char *b = dmap->raw_buf + (buf - dmap->raw_buf_phys);

		if (gus_audio_bits == 8)
			gus_uninterleave8(b, total_count);
		else
			gus_uninterleave16((short *) b, total_count / 2);
	}
	gus_transfer_output_block(dev, buf, total_count, intrflag, 0);
}

static void gus_audio_start_input(int dev, unsigned long buf, int count,
		      int intrflag)
{
	unsigned long flags;
	unsigned char mode;

	save_flags(flags);
	cli();

	DMAbuf_start_dma(dev, buf, count, DMA_MODE_READ);
	mode = 0xa0;		/* DMA IRQ enabled, invert MSB */

	if (audio_devs[dev]->dmap_in->dma > 3)
		mode |= 0x04;	/* 16 bit DMA channel */
	if (gus_audio_channels > 1)
		mode |= 0x02;	/* Stereo */
	mode |= 0x01;		/* DMA enable */

	gus_write8(0x49, mode);
	restore_flags(flags);
}

static int gus_audio_prepare_for_input(int dev, int bsize, int bcount)
{
	unsigned int rate;

	gus_audio_bsize = bsize;
	audio_devs[dev]->dmap_in->flags |= DMA_NODMA;
	rate = (((9878400 + gus_audio_speed / 2) / (gus_audio_speed + 2)) + 8) / 16;

	gus_write8(0x48, rate & 0xff);	/* Set sampling rate */

	if (gus_audio_bits != 8)
	{
/*		printk("GUS Error: 16 bit recording not supported\n");*/
		return -EINVAL;
	}
	return 0;
}

static int gus_audio_prepare_for_output(int dev, int bsize, int bcount)
{
	int i;

	long mem_ptr, mem_size;

	audio_devs[dev]->dmap_out->flags |= DMA_NODMA | DMA_NOTIMEOUT;
	mem_ptr = 0;
	mem_size = gus_mem_size / gus_audio_channels;

	if (mem_size > (256 * 1024))
		mem_size = 256 * 1024;

	pcm_bsize = bsize / gus_audio_channels;
	pcm_head = pcm_tail = pcm_qlen = 0;

	pcm_nblk = 2;		/* MAX_PCM_BUFFERS; */
	if ((pcm_bsize * pcm_nblk) > mem_size)
		pcm_nblk = mem_size / pcm_bsize;

	for (i = 0; i < pcm_nblk; i++)
		pcm_datasize[i] = 0;

	pcm_banksize = pcm_nblk * pcm_bsize;

	if (gus_audio_bits != 8 && pcm_banksize == (256 * 1024))
		pcm_nblk--;
	gus_write8(0x41, 0);	/* Disable GF1 DMA */
	return 0;
}

static int gus_local_qlen(int dev)
{
	return pcm_qlen;
}


static struct audio_driver gus_audio_driver =
{
	owner:		THIS_MODULE,
	open:		gus_audio_open,
	close:		gus_audio_close,
	output_block:	gus_audio_output_block,
	start_input:	gus_audio_start_input,
	ioctl:		gus_audio_ioctl,
	prepare_for_input:	gus_audio_prepare_for_input,
	prepare_for_output:	gus_audio_prepare_for_output,
	halt_io:	gus_audio_reset,
	local_qlen:	gus_local_qlen,
};

static void guswave_setup_voice(int dev, int voice, int chn)
{
	struct channel_info *info = &synth_devs[dev]->chn_info[chn];

	guswave_set_instr(dev, voice, info->pgm_num);
	voices[voice].expression_vol = info->controllers[CTL_EXPRESSION];	/* Just MSB */
	voices[voice].main_vol = (info->controllers[CTL_MAIN_VOLUME] * 100) / (unsigned) 128;
	voices[voice].panning = (info->controllers[CTL_PAN] * 2) - 128;
	voices[voice].bender = 0;
	voices[voice].bender_range = info->bender_range;

	if (chn == 9)
		voices[voice].fixed_pitch = 1;
}

static void guswave_bender(int dev, int voice, int value)
{
	int freq;
	unsigned long   flags;

	voices[voice].bender = value - 8192;
	freq = compute_finetune(voices[voice].orig_freq, value - 8192, voices[voice].bender_range, 0);
	voices[voice].current_freq = freq;

	save_flags(flags);
	cli();
	gus_select_voice(voice);
	gus_voice_freq(freq);
	restore_flags(flags);
}

static int guswave_alloc(int dev, int chn, int note, struct voice_alloc_info *alloc)
{
	int i, p, best = -1, best_time = 0x7fffffff;

	p = alloc->ptr;
	/*
	 * First look for a completely stopped voice
	 */

	for (i = 0; i < alloc->max_voice; i++)
	{
		if (alloc->map[p] == 0)
		{
			alloc->ptr = p;
			return p;
		}
		if (alloc->alloc_times[p] < best_time)
		{
			best = p;
			best_time = alloc->alloc_times[p];
		}
		p = (p + 1) % alloc->max_voice;
	}

	/*
	 * Then look for a releasing voice
	 */

	for (i = 0; i < alloc->max_voice; i++)
	{
		if (alloc->map[p] == 0xffff)
		{
			alloc->ptr = p;
			return p;
		}
		p = (p + 1) % alloc->max_voice;
	}
	if (best >= 0)
		p = best;

	alloc->ptr = p;
	return p;
}

static struct synth_operations guswave_operations =
{
	owner:		THIS_MODULE,
	id:		"GUS",
	info:		&gus_info,
	midi_dev:	0,
	synth_type:	SYNTH_TYPE_SAMPLE,
	synth_subtype:	SAMPLE_TYPE_GUS,
	open:		guswave_open,
	close:		guswave_close,
	ioctl:		guswave_ioctl,
	kill_note:	guswave_kill_note,
	start_note:	guswave_start_note,
	set_instr:	guswave_set_instr,
	reset:		guswave_reset,
	hw_control:	guswave_hw_control,
	load_patch:	guswave_load_patch,
	aftertouch:	guswave_aftertouch,
	controller:	guswave_controller,
	panning:	guswave_panning,
	volume_method:	guswave_volume_method,
	bender:		guswave_bender,
	alloc_voice:	guswave_alloc,
	setup_voice:	guswave_setup_voice
};

static void set_input_volumes(void)
{
	unsigned long flags;
	unsigned char mask = 0xff & ~0x06;	/* Just line out enabled */

	if (have_gus_max)	/* Don't disturb GUS MAX */
		return;

	save_flags(flags);
	cli();

	/*
	 *    Enable channels having vol > 10%
	 *      Note! bit 0x01 means the line in DISABLED while 0x04 means
	 *            the mic in ENABLED.
	 */
	if (gus_line_vol > 10)
		mask &= ~0x01;
	if (gus_mic_vol > 10)
		mask |= 0x04;

	if (recording_active)
	{
		/*
		 *    Disable channel, if not selected for recording
		 */
		if (!(gus_recmask & SOUND_MASK_LINE))
			mask |= 0x01;
		if (!(gus_recmask & SOUND_MASK_MIC))
			mask &= ~0x04;
	}
	mix_image &= ~0x07;
	mix_image |= mask & 0x07;
	outb((mix_image), u_Mixer);

	restore_flags(flags);
}

#define MIX_DEVS	(SOUND_MASK_MIC|SOUND_MASK_LINE| \
			 SOUND_MASK_SYNTH|SOUND_MASK_PCM)

int gus_default_mixer_ioctl(int dev, unsigned int cmd, caddr_t arg)
{
	int vol, val;

	if (((cmd >> 8) & 0xff) != 'M')
		return -EINVAL;

	if (!access_ok(VERIFY_WRITE, (int *)arg, sizeof(int)))
		return -EFAULT;

	if (_SIOC_DIR(cmd) & _SIOC_WRITE) 
	{
		if (__get_user(val, (int *) arg))
			return -EFAULT;

		switch (cmd & 0xff) 
		{
			case SOUND_MIXER_RECSRC:
				gus_recmask = val & MIX_DEVS;
				if (!(gus_recmask & (SOUND_MASK_MIC | SOUND_MASK_LINE)))
					gus_recmask = SOUND_MASK_MIC;
				/* Note! Input volumes are updated during next open for recording */
				val = gus_recmask;
				break;

			case SOUND_MIXER_MIC:
				vol = val & 0xff;
				if (vol < 0)
					vol = 0;
				if (vol > 100)
					vol = 100;
				gus_mic_vol = vol;
				set_input_volumes();
				val = vol | (vol << 8);
				break;
				
			case SOUND_MIXER_LINE:
				vol = val & 0xff;
				if (vol < 0)
					vol = 0;
				if (vol > 100)
					vol = 100;
				gus_line_vol = vol;
				set_input_volumes();
				val = vol | (vol << 8);
				break;

			case SOUND_MIXER_PCM:
				gus_pcm_volume = val & 0xff;
				if (gus_pcm_volume < 0)
					gus_pcm_volume = 0;
				if (gus_pcm_volume > 100)
					gus_pcm_volume = 100;
				gus_audio_update_volume();
				val = gus_pcm_volume | (gus_pcm_volume << 8);
				break;

			case SOUND_MIXER_SYNTH:
				gus_wave_volume = val & 0xff;
				if (gus_wave_volume < 0)
					gus_wave_volume = 0;
				if (gus_wave_volume > 100)
					gus_wave_volume = 100;
				if (active_device == GUS_DEV_WAVE) 
				{
					int voice;
					for (voice = 0; voice < nr_voices; voice++)
					dynamic_volume_change(voice);	/* Apply the new vol */
				}
				val = gus_wave_volume | (gus_wave_volume << 8);
				break;

			default:
				return -EINVAL;
		}
	}
	else
	{
		switch (cmd & 0xff) 
		{
			/*
			 * Return parameters
			 */
			case SOUND_MIXER_RECSRC:
				val = gus_recmask;
				break;