gus_wave.c

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	/*
	 * Copy the header from user space but ignore the first bytes which have
	 * been transferred already.
	 */

	copy_from_user(&((char *) &patch)[offs], &(addr)[offs], sizeof_patch - offs);

	if (patch.mode & WAVE_ROM)
		return -EINVAL;
	if (gus_mem_size == 0)
		return -ENOSPC;

	instr = patch.instr_no;

	if (instr < 0 || instr > MAX_PATCH)
	{
/*		printk(KERN_ERR "GUS: Invalid patch number %d\n", instr);*/
		return -EINVAL;
	}
	if (count < patch.len)
	{
/*		printk(KERN_ERR "GUS Warning: Patch record too short (%d<%d)\n", count, (int) patch.len);*/
		patch.len = count;
	}
	if (patch.len <= 0 || patch.len > gus_mem_size)
	{
/*		printk(KERN_ERR "GUS: Invalid sample length %d\n", (int) patch.len);*/
		return -EINVAL;
	}
	if (patch.mode & WAVE_LOOPING)
	{
		if (patch.loop_start < 0 || patch.loop_start >= patch.len)
		{
/*			printk(KERN_ERR "GUS: Invalid loop start\n");*/
			return -EINVAL;
		}
		if (patch.loop_end < patch.loop_start || patch.loop_end > patch.len)
		{
/*			printk(KERN_ERR "GUS: Invalid loop end\n");*/
			return -EINVAL;
		}
	}
	free_mem_ptr = (free_mem_ptr + 31) & ~31;	/* 32 byte alignment */

	if (patch.mode & WAVE_16_BITS)
	{
		/*
		 * 16 bit samples must fit one 256k bank.
		 */
		if (patch.len >= GUS_BANK_SIZE)
		{
/*			 printk("GUS: Sample (16 bit) too long %d\n", (int) patch.len);*/
			return -ENOSPC;
		}
		if ((free_mem_ptr / GUS_BANK_SIZE) !=
			((free_mem_ptr + patch.len) / GUS_BANK_SIZE))
		{
			unsigned long   tmp_mem =	
				/* Align to 256K */
					((free_mem_ptr / GUS_BANK_SIZE) + 1) * GUS_BANK_SIZE;

			if ((tmp_mem + patch.len) > gus_mem_size)
				return -ENOSPC;

			free_mem_ptr = tmp_mem;		/* This leaves unusable memory */
		}
	}
	if ((free_mem_ptr + patch.len) > gus_mem_size)
		return -ENOSPC;

	sample_ptrs[free_sample] = free_mem_ptr;

	/*
	 * Tremolo is not possible with envelopes
	 */

	if (patch.mode & WAVE_ENVELOPES)
		patch.mode &= ~WAVE_TREMOLO;

	if (!(patch.mode & WAVE_FRACTIONS))
	{
		  patch.fractions = 0;
	}
	memcpy((char *) &samples[free_sample], &patch, sizeof_patch);

	/*
	 * Link this_one sample to the list of samples for patch 'instr'.
	 */

	samples[free_sample].key = patch_table[instr];
	patch_table[instr] = free_sample;

	/*
	 * Use DMA to transfer the wave data to the DRAM
	 */

	left = patch.len;
	src_offs = 0;
	target = free_mem_ptr;

	while (left)		/* Not completely transferred yet */
	{
		blk_sz = audio_devs[gus_devnum]->dmap_out->bytes_in_use;
		if (blk_sz > left)
			blk_sz = left;

		/*
		 * DMA cannot cross bank (256k) boundaries. Check for that.
		 */
		 
		blk_end = target + blk_sz;

		if ((target / GUS_BANK_SIZE) != (blk_end / GUS_BANK_SIZE))
		{
			/* Split the block */
			blk_end &= ~(GUS_BANK_SIZE - 1);
			blk_sz = blk_end - target;
		}
		if (gus_no_dma)
		{
			/*
			 * For some reason the DMA is not possible. We have to use PIO.
			 */
			long i;
			unsigned char data;

			for (i = 0; i < blk_sz; i++)
			{
				get_user(*(unsigned char *) &data, (unsigned char *) &((addr)[sizeof_patch + i]));
				if (patch.mode & WAVE_UNSIGNED)
					if (!(patch.mode & WAVE_16_BITS) || (i & 0x01))
						data ^= 0x80;	/* Convert to signed */
				gus_poke(target + i, data);
			}
		}
		else
		{
			unsigned long address, hold_address;
			unsigned char dma_command;
			unsigned long flags;

			if (audio_devs[gus_devnum]->dmap_out->raw_buf == NULL)
			{
				printk(KERN_ERR "GUS: DMA buffer == NULL\n");
				return -ENOSPC;
			}
			/*
			 * OK, move now. First in and then out.
			 */

			copy_from_user(audio_devs[gus_devnum]->dmap_out->raw_buf, &(addr)[sizeof_patch + src_offs], blk_sz);

			save_flags(flags);
			cli();
			/******** INTERRUPTS DISABLED NOW ********/
			gus_write8(0x41, 0);	/* Disable GF1 DMA */
			DMAbuf_start_dma(gus_devnum, audio_devs[gus_devnum]->dmap_out->raw_buf_phys,
				blk_sz, DMA_MODE_WRITE);

			/*
			 * Set the DRAM address for the wave data
			 */

			if (iw_mode)
			{
				/* Different address translation in enhanced mode */

				unsigned char   hi;

				if (gus_dma > 4)
					address = target >> 1;	/* Convert to 16 bit word address */
				else
					address = target;

				hi = (unsigned char) ((address >> 16) & 0xf0);
				hi += (unsigned char) (address & 0x0f);

				gus_write16(0x42, (address >> 4) & 0xffff);	/* DMA address (low) */
				gus_write8(0x50, hi);
			}
			else
			{
				address = target;
				if (audio_devs[gus_devnum]->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 */
			}

			/*
			 * Start the DMA transfer
			 */

			dma_command = 0x21;		/* IRQ enable, DMA start */
			if (patch.mode & WAVE_UNSIGNED)
				dma_command |= 0x80;	/* Invert MSB */
			if (patch.mode & WAVE_16_BITS)
				dma_command |= 0x40;	/* 16 bit _DATA_ */
			if (audio_devs[gus_devnum]->dmap_out->dma > 3)
				dma_command |= 0x04;	/* 16 bit DMA _channel_ */
			
			gus_write8(0x41, dma_command);	/* Lets go luteet (=bugs) */

			/*
			 * Sleep here until the DRAM DMA done interrupt is served
			 */
			active_device = GUS_DEV_WAVE;

			if (!interruptible_sleep_on_timeout(&dram_sleeper, HZ))
				printk("GUS: DMA Transfer timed out\n");
			restore_flags(flags);
		}

		/*
		 * Now the next part
		 */

		left -= blk_sz;
		src_offs += blk_sz;
		target += blk_sz;

		gus_write8(0x41, 0);	/* Stop DMA */
	}

	free_mem_ptr += patch.len;
	free_sample++;
	return 0;
}

static void guswave_hw_control(int dev, unsigned char *event_rec)
{
	int voice, cmd;
	unsigned short p1, p2;
	unsigned int plong;
	unsigned flags;

	cmd = event_rec[2];
	voice = event_rec[3];
	p1 = *(unsigned short *) &event_rec[4];
	p2 = *(unsigned short *) &event_rec[6];
	plong = *(unsigned int *) &event_rec[4];

	if ((voices[voice].volume_irq_mode == VMODE_START_NOTE) &&
		(cmd != _GUS_VOICESAMPLE) && (cmd != _GUS_VOICE_POS))
		do_volume_irq(voice);

	switch (cmd)
	{
		case _GUS_NUMVOICES:
			save_flags(flags);
			cli();
			gus_select_voice(voice);
			gus_select_max_voices(p1);
			restore_flags(flags);
			break;

		case _GUS_VOICESAMPLE:
			guswave_set_instr(dev, voice, p1);
			break;

		case _GUS_VOICEON:
			save_flags(flags);
			cli();
			gus_select_voice(voice);
			p1 &= ~0x20;	/* Don't allow interrupts */
			gus_voice_on(p1);
			restore_flags(flags);
			break;

		case _GUS_VOICEOFF:
			save_flags(flags);
			cli();
			gus_select_voice(voice);
			gus_voice_off();
			restore_flags(flags);
			break;

		case _GUS_VOICEFADE:
			gus_voice_fade(voice);
			break;

		case _GUS_VOICEMODE:
			save_flags(flags);
			cli();
			gus_select_voice(voice);
			p1 &= ~0x20;	/* Don't allow interrupts */
			gus_voice_mode(p1);
			restore_flags(flags);
			break;

		case _GUS_VOICEBALA:
			save_flags(flags);
			cli();
			gus_select_voice(voice);
			gus_voice_balance(p1);
			restore_flags(flags);
			break;

		case _GUS_VOICEFREQ:
			save_flags(flags);
			cli();
			gus_select_voice(voice);
			gus_voice_freq(plong);
			restore_flags(flags);
			break;

		case _GUS_VOICEVOL:
			save_flags(flags);
			cli();
			gus_select_voice(voice);
			gus_voice_volume(p1);
			restore_flags(flags);
			break;

		case _GUS_VOICEVOL2:	/* Just update the software voice level */
			voices[voice].initial_volume = voices[voice].current_volume = p1;
			break;

		case _GUS_RAMPRANGE:
			if (voices[voice].mode & WAVE_ENVELOPES)
				break;	/* NO-NO */
			save_flags(flags);
			cli();
			gus_select_voice(voice);
			gus_ramp_range(p1, p2);
			restore_flags(flags);
			break;

		case _GUS_RAMPRATE:
			if (voices[voice].mode & WAVE_ENVELOPES)
				break;	/* NJET-NJET */
			save_flags(flags);
			cli();
			gus_select_voice(voice);
			gus_ramp_rate(p1, p2);
			restore_flags(flags);
			break;

		case _GUS_RAMPMODE:
			if (voices[voice].mode & WAVE_ENVELOPES)
				break;	/* NO-NO */
			save_flags(flags);
			cli();
			gus_select_voice(voice);
			p1 &= ~0x20;	/* Don't allow interrupts */
			gus_ramp_mode(p1);
			restore_flags(flags);
			break;

		case _GUS_RAMPON:
			if (voices[voice].mode & WAVE_ENVELOPES)
				break;	/* EI-EI */
			save_flags(flags);
			cli();
			gus_select_voice(voice);
			p1 &= ~0x20;	/* Don't allow interrupts */
			gus_rampon(p1);
			restore_flags(flags);
			break;

		case _GUS_RAMPOFF:
			if (voices[voice].mode & WAVE_ENVELOPES)
				break;	/* NEJ-NEJ */
			save_flags(flags);
			cli();
			gus_select_voice(voice);
			gus_rampoff();
			restore_flags(flags);
			break;

		case _GUS_VOLUME_SCALE:
			volume_base = p1;
			volume_scale = p2;
			break;

		case _GUS_VOICE_POS:
			save_flags(flags);
			cli();
			gus_select_voice(voice);
			gus_set_voice_pos(voice, plong);
			restore_flags(flags);
			break;

		default:
	}
}

static int gus_audio_set_speed(int speed)
{
	if (speed <= 0)
		speed = gus_audio_speed;

	if (speed < 4000)
		speed = 4000;

	if (speed > 44100)
		speed = 44100;

	gus_audio_speed = speed;

	if (only_read_access)
	{
		/* Compute nearest valid recording speed  and return it */

		/* speed = (9878400 / (gus_audio_speed + 2)) / 16; */
		speed = (((9878400 + gus_audio_speed / 2) / (gus_audio_speed + 2)) + 8) / 16;
		speed = (9878400 / (speed * 16)) - 2;
	}
	return speed;
}

static int gus_audio_set_channels(int channels)
{
	if (!channels)
		return gus_audio_channels;
	if (channels > 2)
		channels = 2;
	if (channels < 1)
		channels = 1;
	gus_audio_channels = channels;
	return channels;
}

static int gus_audio_set_bits(int bits)
{
	if (!bits)
		return gus_audio_bits;

	if (bits != 8 && bits != 16)
		bits = 8;

	if (only_8_bits)
		bits = 8;

	gus_audio_bits = bits;
	return bits;
}

static int gus_audio_ioctl(int dev, unsigned int cmd, caddr_t arg)
{
	int val;

	switch (cmd) 
	{
		case SOUND_PCM_WRITE_RATE:
			if (get_user(val, (int *)arg))
				return -EFAULT;
			val = gus_audio_set_speed(val);
			break;

		case SOUND_PCM_READ_RATE:
			val = gus_audio_speed;
			break;

		case SNDCTL_DSP_STEREO:
			if (get_user(val, (int *)arg))
				return -EFAULT;
			val = gus_audio_set_channels(val + 1) - 1;
			break;

		case SOUND_PCM_WRITE_CHANNELS:
			if (get_user(val, (int *)arg))
				return -EFAULT;
			val = gus_audio_set_channels(val);
			break;

		case SOUND_PCM_READ_CHANNELS:
			val = gus_audio_channels;
			break;
		
		case SNDCTL_DSP_SETFMT:
			if (get_user(val, (int *)arg))
				return -EFAULT;
			val = gus_audio_set_bits(val);
			break;
		
		case SOUND_PCM_READ_BITS:
			val = gus_audio_bits;
			break;
		
		case SOUND_PCM_WRITE_FILTER:		/* NOT POSSIBLE */
		case SOUND_PCM_READ_FILTER:
			val = -EINVAL;
			break;
		default:
			return -EINVAL;
	}
	return put_user(val, (int *)arg);
}

static void gus_audio_reset(int dev)
{
	if (recording_active)
	{
		gus_write8(0x49, 0x00);	/* Halt recording */
		set_input_volumes();
	}
}

static int saved_iw_mode;	/* A hack hack hack */

static int gus_audio_open(int dev, int mode)
{
	if (gus_busy)
		return -EBUSY;

	if (gus_pnp_flag && mode & OPEN_READ)
	{
/*		printk(KERN_ERR "GUS: Audio device #%d is playback only.\n", dev);*/
		return -EIO;
	}
	gus_initialize();

	gus_busy = 1;
	active_device = 0;

	saved_iw_mode = iw_mode;
	if (iw_mode)
	{
		/* There are some problems with audio in enhanced mode so disable it */
		gus_write8(0x19, gus_read8(0x19) & ~0x01);	/* Disable enhanced mode */
		iw_mode = 0;
	}

	gus_reset();
	reset_sample_memory();
	gus_select_max_voices(14);

	pcm_active = 0;
	dma_active = 0;
	pcm_opened = 1;
	if (mode & OPEN_READ)
	{
		recording_active = 1;
		set_input_volumes();
	}
	only_read_access = !(mode & OPEN_WRITE);
	only_8_bits = mode & OPEN_READ;
	if (only_8_bits)
		audio_devs[dev]->format_mask = AFMT_U8;
	else
		audio_devs[dev]->format_mask = AFMT_U8 | AFMT_S16_LE;

	return 0;
}

static void gus_audio_close(int dev)
{
	iw_mode = saved_iw_mode;
	gus_reset();
	gus_busy = 0;
	pcm_opened = 0;
	active_device = 0;

	if (recording_active)
	{
		gus_write8(0x49, 0x00);	/* Halt recording */
		set_input_volumes();
	}
	recording_active = 0;
}

static void gus_audio_update_volume(void)
{
	unsigned long flags;
	int voice;

	if (pcm_active && pcm_opened)