diff options
Diffstat (limited to 'sound/oss/gus_midi.c')
| -rw-r--r-- | sound/oss/gus_midi.c | 256 |
1 files changed, 256 insertions, 0 deletions
diff --git a/sound/oss/gus_midi.c b/sound/oss/gus_midi.c new file mode 100644 index 000000000000..b48f57c24e48 --- /dev/null +++ b/sound/oss/gus_midi.c @@ -0,0 +1,256 @@ +/* + * 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 <linux/spinlock.h> +#include "sound_config.h" + +#include "gus.h" +#include "gus_hw.h" + +static int midi_busy, input_opened; +static int my_dev; +static int output_used; +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; +extern spinlock_t gus_lock; + +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; + + spin_lock_irqsave(&gus_lock, flags); + + 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); + } + + spin_unlock_irqrestore(&gus_lock,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 + */ + spin_lock_irqsave(&gus_lock, flags); + + while (qlen && dump_to_midi(tmp_queue[qhead])) + { + qlen--; + qhead++; + } + spin_unlock_irqrestore(&gus_lock,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 + */ + spin_lock_irqsave(&gus_lock, flags); + + tmp_queue[qtail] = midi_byte; + qlen++; + qtail++; + + spin_unlock_irqrestore(&gus_lock,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; + + spin_lock_irqsave(&gus_lock, flags); + + if (qlen && dump_to_midi(tmp_queue[qhead])) + { + qlen--; + qhead++; + } + spin_unlock_irqrestore(&gus_lock,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; + int timeout = 10; + + spin_lock(&gus_lock); + + 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); + } + } + } + spin_unlock(&gus_lock); +} |