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/*
* sound/gus2_midi.c
*
* The low level driver for the GUS Midi Interface.
*
*
* 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.
*
* Changes:
* 11-10-2000 Bartlomiej Zolnierkiewicz <bkz@linux-ide.org>
* Added __init to gus_midi_init()
*/
#include <linux/init.h>
#include "sound_config.h"
#include "gus.h"
#include "gus_hw.h"
static int midi_busy = 0, input_opened = 0;
static int my_dev;
static int output_used = 0;
static volatile unsigned char gus_midi_control;
static void (*midi_input_intr) (int dev, unsigned char data);
static unsigned char tmp_queue[256];
extern int gus_pnp_flag;
static volatile int qlen;
static volatile unsigned char qhead, qtail;
extern int gus_base, gus_irq, gus_dma;
extern int *gus_osp;
static int GUS_MIDI_STATUS(void)
{
return inb(u_MidiStatus);
}
static int gus_midi_open(int dev, int mode, void (*input) (int dev, unsigned char data), void (*output) (int dev))
{
if (midi_busy)
{
/* printk("GUS: Midi busy\n");*/
return -EBUSY;
}
outb((MIDI_RESET), u_MidiControl);
gus_delay();
gus_midi_control = 0;
input_opened = 0;
if (mode == OPEN_READ || mode == OPEN_READWRITE)
if (!gus_pnp_flag)
{
gus_midi_control |= MIDI_ENABLE_RCV;
input_opened = 1;
}
outb((gus_midi_control), u_MidiControl); /* Enable */
midi_busy = 1;
qlen = qhead = qtail = output_used = 0;
midi_input_intr = input;
return 0;
}
static int dump_to_midi(unsigned char midi_byte)
{
unsigned long flags;
int ok = 0;
output_used = 1;
save_flags(flags);
cli();
if (GUS_MIDI_STATUS() & MIDI_XMIT_EMPTY)
{
ok = 1;
outb((midi_byte), u_MidiData);
}
else
{
/*
* Enable Midi xmit interrupts (again)
*/
gus_midi_control |= MIDI_ENABLE_XMIT;
outb((gus_midi_control), u_MidiControl);
}
restore_flags(flags);
return ok;
}
static void gus_midi_close(int dev)
{
/*
* Reset FIFO pointers, disable intrs
*/
outb((MIDI_RESET), u_MidiControl);
midi_busy = 0;
}
static int gus_midi_out(int dev, unsigned char midi_byte)
{
unsigned long flags;
/*
* Drain the local queue first
*/
save_flags(flags);
cli();
while (qlen && dump_to_midi(tmp_queue[qhead]))
{
qlen--;
qhead++;
}
restore_flags(flags);
/*
* Output the byte if the local queue is empty.
*/
if (!qlen)
if (dump_to_midi(midi_byte))
return 1; /*
* OK
*/
/*
* Put to the local queue
*/
if (qlen >= 256)
return 0; /*
* Local queue full
*/
save_flags(flags);
cli();
tmp_queue[qtail] = midi_byte;
qlen++;
qtail++;
restore_flags(flags);
return 1;
}
static int gus_midi_start_read(int dev)
{
return 0;
}
static int gus_midi_end_read(int dev)
{
return 0;
}
static void gus_midi_kick(int dev)
{
}
static int gus_midi_buffer_status(int dev)
{
unsigned long flags;
if (!output_used)
return 0;
save_flags(flags);
cli();
if (qlen && dump_to_midi(tmp_queue[qhead]))
{
qlen--;
qhead++;
}
restore_flags(flags);
return (qlen > 0) | !(GUS_MIDI_STATUS() & MIDI_XMIT_EMPTY);
}
#define MIDI_SYNTH_NAME "Gravis Ultrasound Midi"
#define MIDI_SYNTH_CAPS SYNTH_CAP_INPUT
#include "midi_synth.h"
static struct midi_operations gus_midi_operations =
{
owner: THIS_MODULE,
info: {"Gravis UltraSound Midi", 0, 0, SNDCARD_GUS},
converter: &std_midi_synth,
in_info: {0},
open: gus_midi_open,
close: gus_midi_close,
outputc: gus_midi_out,
start_read: gus_midi_start_read,
end_read: gus_midi_end_read,
kick: gus_midi_kick,
buffer_status: gus_midi_buffer_status,
};
void __init gus_midi_init(struct address_info *hw_config)
{
int dev = sound_alloc_mididev();
if (dev == -1)
{
printk(KERN_INFO "gus_midi: Too many midi devices detected\n");
return;
}
outb((MIDI_RESET), u_MidiControl);
std_midi_synth.midi_dev = my_dev = dev;
hw_config->slots[2] = dev;
midi_devs[dev] = &gus_midi_operations;
sequencer_init();
return;
}
void gus_midi_interrupt(int dummy)
{
volatile unsigned char stat, data;
unsigned long flags;
int timeout = 10;
save_flags(flags);
cli();
while (timeout-- > 0 && (stat = GUS_MIDI_STATUS()) & (MIDI_RCV_FULL | MIDI_XMIT_EMPTY))
{
if (stat & MIDI_RCV_FULL)
{
data = inb(u_MidiData);
if (input_opened)
midi_input_intr(my_dev, data);
}
if (stat & MIDI_XMIT_EMPTY)
{
while (qlen && dump_to_midi(tmp_queue[qhead]))
{
qlen--;
qhead++;
}
if (!qlen)
{
/*
* Disable Midi output interrupts, since no data in the buffer
*/
gus_midi_control &= ~MIDI_ENABLE_XMIT;
outb((gus_midi_control), u_MidiControl);
outb((gus_midi_control), u_MidiControl);
}
}
}
restore_flags(flags);
}
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