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/*
* sound/v_midi.c
*
* The low level driver for the Sound Blaster DS chips.
*
*
* Copyright (C) by Hannu Savolainen 1993-1996
*
* USS/Lite 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
* Alan Cox Modularisation, changed memory allocations
* Christoph Hellwig Adapted to module_init/module_exit
*
* Status
* Untested
*/
#include <linux/init.h>
#include <linux/module.h>
#include "sound_config.h"
#include "v_midi.h"
static vmidi_devc *v_devc[2] = { NULL, NULL};
static int midi1,midi2;
static void *midi_mem = NULL;
/*
* The DSP channel can be used either for input or output. Variable
* 'sb_irq_mode' will be set when the program calls read or write first time
* after open. Current version doesn't support mode changes without closing
* and reopening the device. Support for this feature may be implemented in a
* future version of this driver.
*/
void (*midi_input_intr) (int dev, unsigned char data);
static int v_midi_open (int dev, int mode,
void (*input) (int dev, unsigned char data),
void (*output) (int dev)
)
{
vmidi_devc *devc = midi_devs[dev]->devc;
unsigned long flags;
if (devc == NULL)
return -(ENXIO);
save_flags (flags);
cli();
if (devc->opened)
{
restore_flags (flags);
return -(EBUSY);
}
devc->opened = 1;
restore_flags (flags);
devc->intr_active = 1;
if (mode & OPEN_READ)
{
devc->input_opened = 1;
devc->midi_input_intr = input;
}
return 0;
}
static void v_midi_close (int dev)
{
vmidi_devc *devc = midi_devs[dev]->devc;
unsigned long flags;
if (devc == NULL)
return;
save_flags (flags);
cli ();
devc->intr_active = 0;
devc->input_opened = 0;
devc->opened = 0;
restore_flags (flags);
}
static int v_midi_out (int dev, unsigned char midi_byte)
{
vmidi_devc *devc = midi_devs[dev]->devc;
vmidi_devc *pdevc = midi_devs[devc->pair_mididev]->devc;
if (devc == NULL)
return -(ENXIO);
if (pdevc->input_opened > 0){
if (MIDIbuf_avail(pdevc->my_mididev) > 500)
return 0;
pdevc->midi_input_intr (pdevc->my_mididev, midi_byte);
}
return 1;
}
static inline int v_midi_start_read (int dev)
{
return 0;
}
static int v_midi_end_read (int dev)
{
vmidi_devc *devc = midi_devs[dev]->devc;
if (devc == NULL)
return -ENXIO;
devc->intr_active = 0;
return 0;
}
/* why -EPERM and not -EINVAL?? */
static inline int v_midi_ioctl (int dev, unsigned cmd, caddr_t arg)
{
return -EPERM;
}
#define MIDI_SYNTH_NAME "Loopback MIDI"
#define MIDI_SYNTH_CAPS SYNTH_CAP_INPUT
#include "midi_synth.h"
static struct midi_operations v_midi_operations =
{
owner: THIS_MODULE,
info: {"Loopback MIDI Port 1", 0, 0, SNDCARD_VMIDI},
converter: &std_midi_synth,
in_info: {0},
open: v_midi_open,
close: v_midi_close,
ioctl: v_midi_ioctl,
outputc: v_midi_out,
start_read: v_midi_start_read,
end_read: v_midi_end_read,
};
static struct midi_operations v_midi_operations2 =
{
owner: THIS_MODULE,
info: {"Loopback MIDI Port 2", 0, 0, SNDCARD_VMIDI},
converter: &std_midi_synth,
in_info: {0},
open: v_midi_open,
close: v_midi_close,
ioctl: v_midi_ioctl,
outputc: v_midi_out,
start_read: v_midi_start_read,
end_read: v_midi_end_read,
};
/*
* We kmalloc just one of these - it makes life simpler and the code
* cleaner and the memory handling far more efficient
*/
struct vmidi_memory
{
/* Must be first */
struct midi_operations m_ops[2];
struct synth_operations s_ops[2];
struct vmidi_devc v_ops[2];
};
static void __init attach_v_midi (struct address_info *hw_config)
{
struct vmidi_memory *m;
/* printk("Attaching v_midi device.....\n"); */
midi1 = sound_alloc_mididev();
if (midi1 == -1)
{
printk(KERN_ERR "v_midi: Too many midi devices detected\n");
return;
}
m=(struct vmidi_memory *)kmalloc(sizeof(struct vmidi_memory), GFP_KERNEL);
if (m == NULL)
{
printk(KERN_WARNING "Loopback MIDI: Failed to allocate memory\n");
sound_unload_mididev(midi1);
return;
}
midi_mem = m;
midi_devs[midi1] = &m->m_ops[0];
midi2 = sound_alloc_mididev();
if (midi2 == -1)
{
printk (KERN_ERR "v_midi: Too many midi devices detected\n");
kfree(m);
sound_unload_mididev(midi1);
return;
}
midi_devs[midi2] = &m->m_ops[1];
/* printk("VMIDI1: %d VMIDI2: %d\n",midi1,midi2); */
/* for MIDI-1 */
v_devc[0] = &m->v_ops[0];
memcpy ((char *) midi_devs[midi1], (char *) &v_midi_operations,
sizeof (struct midi_operations));
v_devc[0]->my_mididev = midi1;
v_devc[0]->pair_mididev = midi2;
v_devc[0]->opened = v_devc[0]->input_opened = 0;
v_devc[0]->intr_active = 0;
v_devc[0]->midi_input_intr = NULL;
midi_devs[midi1]->devc = v_devc[0];
midi_devs[midi1]->converter = &m->s_ops[0];
std_midi_synth.midi_dev = midi1;
memcpy ((char *) midi_devs[midi1]->converter, (char *) &std_midi_synth,
sizeof (struct synth_operations));
midi_devs[midi1]->converter->id = "V_MIDI 1";
/* for MIDI-2 */
v_devc[1] = &m->v_ops[1];
memcpy ((char *) midi_devs[midi2], (char *) &v_midi_operations2,
sizeof (struct midi_operations));
v_devc[1]->my_mididev = midi2;
v_devc[1]->pair_mididev = midi1;
v_devc[1]->opened = v_devc[1]->input_opened = 0;
v_devc[1]->intr_active = 0;
v_devc[1]->midi_input_intr = NULL;
midi_devs[midi2]->devc = v_devc[1];
midi_devs[midi2]->converter = &m->s_ops[1];
std_midi_synth.midi_dev = midi2;
memcpy ((char *) midi_devs[midi2]->converter, (char *) &std_midi_synth,
sizeof (struct synth_operations));
midi_devs[midi2]->converter->id = "V_MIDI 2";
sequencer_init();
/* printk("Attached v_midi device\n"); */
}
static inline int __init probe_v_midi(struct address_info *hw_config)
{
return(1); /* always OK */
}
static void __exit unload_v_midi(struct address_info *hw_config)
{
sound_unload_mididev(midi1);
sound_unload_mididev(midi2);
kfree(midi_mem);
}
static struct address_info cfg; /* dummy */
static int __init init_vmidi(void)
{
printk("MIDI Loopback device driver\n");
if (!probe_v_midi(&cfg))
return -ENODEV;
attach_v_midi(&cfg);
return 0;
}
static void __exit cleanup_vmidi(void)
{
unload_v_midi(&cfg);
}
module_init(init_vmidi);
module_exit(cleanup_vmidi);
MODULE_LICENSE("GPL");
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