mpu401.c

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/*
 * sound/mpu401.c
 *
 * The low level driver for Roland MPU-401 compatible Midi cards.
 */
/*
 * Copyright (C) by Hannu Savolainen 1993-1997
 *
 * OSS/Free for Linux is distributed under the GNU GENERAL PUBLIC LICENSE (GPL)
 * Version 2 (June 1991). See the "COPYING" file distributed with this software
 * for more info.
 *
 *
 * Thomas Sailer	ioctl code reworked (vmalloc/vfree removed)
 * Alan Cox		modularisation, use normal request_irq, use dev_id
 * Bartlomiej Zolnierkiewicz	removed some __init to allow using many drivers
 */

#include <linux/module.h>
#include <linux/init.h>

#define USE_SEQ_MACROS
#define USE_SIMPLE_MACROS

#include "sound_config.h"

#include "coproc.h"
#include "mpu401.h"

static int      timer_mode = TMR_INTERNAL, timer_caps = TMR_INTERNAL;

struct mpu_config
{
	int             base;	/*
				 * I/O base
				 */
	int             irq;
	int             opened;	/*
				 * Open mode
				 */
	int             devno;
	int             synthno;
	int             uart_mode;
	int             initialized;
	int             mode;
#define MODE_MIDI	1
#define MODE_SYNTH	2
	unsigned char   version, revision;
	unsigned int    capabilities;
#define MPU_CAP_INTLG	0x10000000
#define MPU_CAP_SYNC	0x00000010
#define MPU_CAP_FSK	0x00000020
#define MPU_CAP_CLS	0x00000040
#define MPU_CAP_SMPTE 	0x00000080
#define MPU_CAP_2PORT	0x00000001
	int             timer_flag;

#define MBUF_MAX	10
#define BUFTEST(dc) if (dc->m_ptr >= MBUF_MAX || dc->m_ptr < 0) \
	{printk( "MPU: Invalid buffer pointer %d/%d, s=%d\n",  dc->m_ptr,  dc->m_left,  dc->m_state);dc->m_ptr--;}
	  int             m_busy;
	  unsigned char   m_buf[MBUF_MAX];
	  int             m_ptr;
	  int             m_state;
	  int             m_left;
	  unsigned char   last_status;
	  void            (*inputintr) (int dev, unsigned char data);
	  int             shared_irq;
	  int            *osp;
  };

#define	DATAPORT(base)   (base)
#define	COMDPORT(base)   (base+1)
#define	STATPORT(base)   (base+1)

static int mpu401_status(struct mpu_config *devc)
{
	return inb(STATPORT(devc->base));
}

#define input_avail(devc)		(!(mpu401_status(devc)&INPUT_AVAIL))
#define output_ready(devc)		(!(mpu401_status(devc)&OUTPUT_READY))

static void write_command(struct mpu_config *devc, unsigned char cmd)
{
	outb(cmd, COMDPORT(devc->base));
}

static int read_data(struct mpu_config *devc)
{
	return inb(DATAPORT(devc->base));
}

static void write_data(struct mpu_config *devc, unsigned char byte)
{
	outb(byte, DATAPORT(devc->base));
}

#define	OUTPUT_READY	0x40
#define	INPUT_AVAIL	0x80
#define	MPU_ACK		0xFE
#define	MPU_RESET	0xFF
#define	UART_MODE_ON	0x3F

static struct mpu_config dev_conf[MAX_MIDI_DEV] =
{
	{0}
};

static int n_mpu_devs = 0;

static int reset_mpu401(struct mpu_config *devc);
static void set_uart_mode(int dev, struct mpu_config *devc, int arg);

static int mpu_timer_init(int midi_dev);
static void mpu_timer_interrupt(void);
static void timer_ext_event(struct mpu_config *devc, int event, int parm);

static struct synth_info mpu_synth_info_proto = {
	"MPU-401 MIDI interface", 
	0, 
	SYNTH_TYPE_MIDI, 
	MIDI_TYPE_MPU401, 
	0, 128, 
	0, 128, 
	SYNTH_CAP_INPUT
};

static struct synth_info mpu_synth_info[MAX_MIDI_DEV];

/*
 * States for the input scanner
 */

#define ST_INIT			0	/* Ready for timing byte or msg */
#define ST_TIMED		1	/* Leading timing byte rcvd */
#define ST_DATABYTE		2	/* Waiting for (nr_left) data bytes */

#define ST_SYSMSG		100	/* System message (sysx etc). */
#define ST_SYSEX		101	/* System exclusive msg */
#define ST_MTC			102	/* Midi Time Code (MTC) qframe msg */
#define ST_SONGSEL		103	/* Song select */
#define ST_SONGPOS		104	/* Song position pointer */

static unsigned char len_tab[] =	/* # of data bytes following a status
					 */
{
	2,			/* 8x */
	2,			/* 9x */
	2,			/* Ax */
	2,			/* Bx */
	1,			/* Cx */
	1,			/* Dx */
	2,			/* Ex */
	0			/* Fx */
};

#define STORE(cmd) \
{ \
	int len; \
	unsigned char obuf[8]; \
	cmd; \
	seq_input_event(obuf, len); \
}

#define _seqbuf obuf
#define _seqbufptr 0
#define _SEQ_ADVBUF(x) len=x

static int mpu_input_scanner(struct mpu_config *devc, unsigned char midic)
{

	switch (devc->m_state)
	{
		case ST_INIT:
			switch (midic)
			{
				case 0xf8:
				/* Timer overflow */
					break;

				case 0xfc:
					printk("<all end>");
			 		break;

				case 0xfd:
					if (devc->timer_flag)
						mpu_timer_interrupt();
					break;

				case 0xfe:
					return MPU_ACK;

				case 0xf0:
				case 0xf1:
				case 0xf2:
				case 0xf3:
				case 0xf4:
				case 0xf5:
				case 0xf6:
				case 0xf7:
					printk("<Trk data rq #%d>", midic & 0x0f);
					break;

				case 0xf9:
					printk("<conductor rq>");
					break;

				case 0xff:
					devc->m_state = ST_SYSMSG;
					break;

				default:
					if (midic <= 0xef)
					{
						/* printk( "mpu time: %d ",  midic); */
						devc->m_state = ST_TIMED;
					}
					else
						printk("<MPU: Unknown event %02x> ", midic);
			}
			break;

		case ST_TIMED:
			{
				int msg = ((int) (midic & 0xf0) >> 4);

				devc->m_state = ST_DATABYTE;

				if (msg < 8)	/* Data byte */
				{
					/* printk( "midi msg (running status) "); */
					msg = ((int) (devc->last_status & 0xf0) >> 4);
					msg -= 8;
					devc->m_left = len_tab[msg] - 1;

					devc->m_ptr = 2;
					devc->m_buf[0] = devc->last_status;
					devc->m_buf[1] = midic;

					if (devc->m_left <= 0)
					{
						devc->m_state = ST_INIT;
						do_midi_msg(devc->synthno, devc->m_buf, devc->m_ptr);
						devc->m_ptr = 0;
					}
				}
				else if (msg == 0xf)	/* MPU MARK */
				{
					devc->m_state = ST_INIT;

					switch (midic)
					{
						case 0xf8:
							/* printk( "NOP "); */
							break;

						case 0xf9:
							/* printk( "meas end "); */
							break;

						case 0xfc:
							/* printk( "data end "); */
							break;

						default:
							printk("Unknown MPU mark %02x\n", midic);
					}
				}
				else
				{
					devc->last_status = midic;
					/* printk( "midi msg "); */
					msg -= 8;
					devc->m_left = len_tab[msg];

					devc->m_ptr = 1;
					devc->m_buf[0] = midic;

					if (devc->m_left <= 0)
					{
						devc->m_state = ST_INIT;
						do_midi_msg(devc->synthno, devc->m_buf, devc->m_ptr);
						devc->m_ptr = 0;
					}
				}
			}
			break;

		case ST_SYSMSG:
			switch (midic)
			{
				case 0xf0:
					printk("<SYX>");
					devc->m_state = ST_SYSEX;
					break;

				case 0xf1:
					devc->m_state = ST_MTC;
					break;

				case 0xf2:
					devc->m_state = ST_SONGPOS;
					devc->m_ptr = 0;
					break;

				case 0xf3:
					devc->m_state = ST_SONGSEL;
					break;

				case 0xf6:
					/* printk( "tune_request\n"); */
					devc->m_state = ST_INIT;

					/*
					 *    Real time messages
					 */
				case 0xf8:
					/* midi clock */
					devc->m_state = ST_INIT;
					timer_ext_event(devc, TMR_CLOCK, 0);
					break;

				case 0xfA:
					devc->m_state = ST_INIT;
					timer_ext_event(devc, TMR_START, 0);
					break;

				case 0xFB:
					devc->m_state = ST_INIT;
					timer_ext_event(devc, TMR_CONTINUE, 0);
					break;

				case 0xFC:
					devc->m_state = ST_INIT;
					timer_ext_event(devc, TMR_STOP, 0);
					break;

				case 0xFE:
					/* active sensing */
					devc->m_state = ST_INIT;
					break;

				case 0xff:
					/* printk( "midi hard reset"); */
					devc->m_state = ST_INIT;
					break;

				default:
					printk("unknown MIDI sysmsg %0x\n", midic);
					devc->m_state = ST_INIT;
			}
			break;

		case ST_MTC:
			devc->m_state = ST_INIT;
			printk("MTC frame %x02\n", midic);
			break;

		case ST_SYSEX:
			if (midic == 0xf7)
			{
				printk("<EOX>");
				devc->m_state = ST_INIT;
			}
			else
				printk("%02x ", midic);
			break;

		case ST_SONGPOS:
			BUFTEST(devc);
			devc->m_buf[devc->m_ptr++] = midic;
			if (devc->m_ptr == 2)
			{
				devc->m_state = ST_INIT;
				devc->m_ptr = 0;
				timer_ext_event(devc, TMR_SPP,
					((devc->m_buf[1] & 0x7f) << 7) |
					(devc->m_buf[0] & 0x7f));
			}
			break;

		case ST_DATABYTE:
			BUFTEST(devc);
			devc->m_buf[devc->m_ptr++] = midic;
			if ((--devc->m_left) <= 0)
			{
				devc->m_state = ST_INIT;
				do_midi_msg(devc->synthno, devc->m_buf, devc->m_ptr);
				devc->m_ptr = 0;
			}
			break;

		default:
			printk("Bad state %d ", devc->m_state);
			devc->m_state = ST_INIT;
	}
	return 1;
}

static void mpu401_input_loop(struct mpu_config *devc)
{
	unsigned long flags;
	int busy;
	int n;

	save_flags(flags);
	cli();
	busy = devc->m_busy;
	devc->m_busy = 1;
	restore_flags(flags);

	if (busy)		/* Already inside the scanner */
		return;

	n = 50;

	while (input_avail(devc) && n-- > 0)
	{
		unsigned char c = read_data(devc);

		if (devc->mode == MODE_SYNTH)
		{
			mpu_input_scanner(devc, c);
		}
		else if (devc->opened & OPEN_READ && devc->inputintr != NULL)
			devc->inputintr(devc->devno, c);
	}
	devc->m_busy = 0;
}

int intchk_mpu401(void *dev_id)
{
	struct mpu_config *devc;
	int dev = (int) dev_id;

	devc = &dev_conf[dev];
	return input_avail(devc);
}

void mpuintr(int irq, void *dev_id, struct pt_regs *dummy)
{
	struct mpu_config *devc;
	int dev = (int) dev_id;

	sti();
	devc = &dev_conf[dev];

	if (input_avail(devc))
	{
		if (devc->base != 0 && (devc->opened & OPEN_READ || devc->mode == MODE_SYNTH))
			mpu401_input_loop(devc);
		else
		{
			/* Dummy read (just to acknowledge the interrupt) */
			read_data(devc);
		}
	}
}

static int mpu401_open(int dev, int mode,
	    void            (*input) (int dev, unsigned char data),
	    void            (*output) (int dev)
)
{
	int err;
	struct mpu_config *devc;

	if (dev < 0 || dev >= num_midis || midi_devs[dev] == NULL)
		return -ENXIO;

	devc = &dev_conf[dev];

	if (devc->opened)
		  return -EBUSY;
	/*
	 *  Verify that the device is really running.
	 *  Some devices (such as Ensoniq SoundScape don't
	 *  work before the on board processor (OBP) is initialized
	 *  by downloading its microcode.
	 */

	if (!devc->initialized)
	{
		if (mpu401_status(devc) == 0xff)	/* Bus float */
		{
			printk(KERN_ERR "mpu401: Device not initialized properly\n");
			return -EIO;
		}
		reset_mpu401(devc);
	}

	if (midi_devs[dev]->coproc)
	{
		if ((err = midi_devs[dev]->coproc->
		     open(midi_devs[dev]->coproc->devc, COPR_MIDI)) < 0)
		{
			printk("MPU-401: Can't access coprocessor device\n");
			return err;
		}
	}
	
	set_uart_mode(dev, devc, 1);
	devc->mode = MODE_MIDI;
	devc->synthno = 0;

	mpu401_input_loop(devc);

	devc->inputintr = input;
	devc->opened = mode;

	return 0;
}

static void mpu401_close(int dev)
{
	struct mpu_config *devc;

	devc = &dev_conf[dev];
	if (devc->uart_mode)
		reset_mpu401(devc);	/*
					 * This disables the UART mode
					 */
	devc->mode = 0;
	devc->inputintr = NULL;

	if (midi_devs[dev]->coproc)
		midi_devs[dev]->coproc->close(midi_devs[dev]->coproc->devc, COPR_MIDI);
	devc->opened = 0;
}

static int mpu401_out(int dev, unsigned char midi_byte)
{
	int timeout;
	unsigned long flags;

	struct mpu_config *devc;

	devc = &dev_conf[dev];

	/*
	 * Sometimes it takes about 30000 loops before the output becomes ready
	 * (After reset). Normally it takes just about 10 loops.
	 */

	for (timeout = 30000; timeout > 0 && !output_ready(devc); timeout--);

	save_flags(flags);
	cli();
	if (!output_ready(devc))
	{
		printk(KERN_WARNING "mpu401: Send data timeout\n");
		restore_flags(flags);
		return 0;
	}
	write_data(devc, midi_byte);
	restore_flags(flags);
	return 1;
}

static int mpu401_command(int dev, mpu_command_rec * cmd)
{
	int i, timeout, ok;
	int ret = 0;
	unsigned long   flags;
	struct mpu_config *devc;

	devc = &dev_conf[dev];

	if (devc->uart_mode)	/*
				 * Not possible in UART mode
				 */
	{
		printk(KERN_WARNING "mpu401: commands not possible in the UART mode\n");
		return -EINVAL;
	}
	/*
	 * Test for input since pending input seems to block the output.
	 */
	if (input_avail(devc))
		mpu401_input_loop(devc);

	/*
	 * Sometimes it takes about 50000 loops before the output becomes ready
	 * (After reset). Normally it takes just about 10 loops.
	 */

	timeout = 50000;
retry:
	if (timeout-- <= 0)