tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * sound/gus2_midi.c
3 *
4 * The low level driver for the GUS Midi Interface.
5 *
6 *
7 * Copyright (C) by Hannu Savolainen 1993-1997
8 *
9 * OSS/Free for Linux is distributed under the GNU GENERAL PUBLIC LICENSE (GPL)
10 * Version 2 (June 1991). See the "COPYING" file distributed with this software
11 * for more info.
12 *
13 * Changes:
14 * 11-10-2000 Bartlomiej Zolnierkiewicz <bkz@linux-ide.org>
15 * Added __init to gus_midi_init()
16 */
17
18#include <linux/init.h>
19#include <linux/spinlock.h>
20#include "sound_config.h"
21
22#include "gus.h"
23#include "gus_hw.h"
24
25static int midi_busy, input_opened;
26static int my_dev;
27static int output_used;
28static volatile unsigned char gus_midi_control;
29static void (*midi_input_intr) (int dev, unsigned char data);
30
31static unsigned char tmp_queue[256];
32extern int gus_pnp_flag;
33static volatile int qlen;
34static volatile unsigned char qhead, qtail;
35extern int gus_base, gus_irq, gus_dma;
36extern int *gus_osp;
37extern spinlock_t gus_lock;
38
39static int GUS_MIDI_STATUS(void)
40{
41 return inb(u_MidiStatus);
42}
43
44static int gus_midi_open(int dev, int mode, void (*input) (int dev, unsigned char data), void (*output) (int dev))
45{
46 if (midi_busy)
47 {
48/* printk("GUS: Midi busy\n");*/
49 return -EBUSY;
50 }
51 outb((MIDI_RESET), u_MidiControl);
52 gus_delay();
53
54 gus_midi_control = 0;
55 input_opened = 0;
56
57 if (mode == OPEN_READ || mode == OPEN_READWRITE)
58 if (!gus_pnp_flag)
59 {
60 gus_midi_control |= MIDI_ENABLE_RCV;
61 input_opened = 1;
62 }
63 outb((gus_midi_control), u_MidiControl); /* Enable */
64
65 midi_busy = 1;
66 qlen = qhead = qtail = output_used = 0;
67 midi_input_intr = input;
68
69 return 0;
70}
71
72static int dump_to_midi(unsigned char midi_byte)
73{
74 unsigned long flags;
75 int ok = 0;
76
77 output_used = 1;
78
79 spin_lock_irqsave(&gus_lock, flags);
80
81 if (GUS_MIDI_STATUS() & MIDI_XMIT_EMPTY)
82 {
83 ok = 1;
84 outb((midi_byte), u_MidiData);
85 }
86 else
87 {
88 /*
89 * Enable Midi xmit interrupts (again)
90 */
91 gus_midi_control |= MIDI_ENABLE_XMIT;
92 outb((gus_midi_control), u_MidiControl);
93 }
94
95 spin_unlock_irqrestore(&gus_lock,flags);
96 return ok;
97}
98
99static void gus_midi_close(int dev)
100{
101 /*
102 * Reset FIFO pointers, disable intrs
103 */
104
105 outb((MIDI_RESET), u_MidiControl);
106 midi_busy = 0;
107}
108
109static int gus_midi_out(int dev, unsigned char midi_byte)
110{
111 unsigned long flags;
112
113 /*
114 * Drain the local queue first
115 */
116 spin_lock_irqsave(&gus_lock, flags);
117
118 while (qlen && dump_to_midi(tmp_queue[qhead]))
119 {
120 qlen--;
121 qhead++;
122 }
123 spin_unlock_irqrestore(&gus_lock,flags);
124
125 /*
126 * Output the byte if the local queue is empty.
127 */
128
129 if (!qlen)
130 if (dump_to_midi(midi_byte))
131 return 1; /*
132 * OK
133 */
134
135 /*
136 * Put to the local queue
137 */
138
139 if (qlen >= 256)
140 return 0; /*
141 * Local queue full
142 */
143 spin_lock_irqsave(&gus_lock, flags);
144
145 tmp_queue[qtail] = midi_byte;
146 qlen++;
147 qtail++;
148
149 spin_unlock_irqrestore(&gus_lock,flags);
150 return 1;
151}
152
153static int gus_midi_start_read(int dev)
154{
155 return 0;
156}
157
158static int gus_midi_end_read(int dev)
159{
160 return 0;
161}
162
163static void gus_midi_kick(int dev)
164{
165}
166
167static int gus_midi_buffer_status(int dev)
168{
169 unsigned long flags;
170
171 if (!output_used)
172 return 0;
173
174 spin_lock_irqsave(&gus_lock, flags);
175
176 if (qlen && dump_to_midi(tmp_queue[qhead]))
177 {
178 qlen--;
179 qhead++;
180 }
181 spin_unlock_irqrestore(&gus_lock,flags);
182 return (qlen > 0) || !(GUS_MIDI_STATUS() & MIDI_XMIT_EMPTY);
183}
184
185#define MIDI_SYNTH_NAME "Gravis Ultrasound Midi"
186#define MIDI_SYNTH_CAPS SYNTH_CAP_INPUT
187#include "midi_synth.h"
188
189static struct midi_operations gus_midi_operations =
190{
191 .owner = THIS_MODULE,
192 .info = {"Gravis UltraSound Midi", 0, 0, SNDCARD_GUS},
193 .converter = &std_midi_synth,
194 .in_info = {0},
195 .open = gus_midi_open,
196 .close = gus_midi_close,
197 .outputc = gus_midi_out,
198 .start_read = gus_midi_start_read,
199 .end_read = gus_midi_end_read,
200 .kick = gus_midi_kick,
201 .buffer_status = gus_midi_buffer_status,
202};
203
204void __init gus_midi_init(struct address_info *hw_config)
205{
206 int dev = sound_alloc_mididev();
207
208 if (dev == -1)
209 {
210 printk(KERN_INFO "gus_midi: Too many midi devices detected\n");
211 return;
212 }
213 outb((MIDI_RESET), u_MidiControl);
214
215 std_midi_synth.midi_dev = my_dev = dev;
216 hw_config->slots[2] = dev;
217 midi_devs[dev] = &gus_midi_operations;
218 sequencer_init();
219 return;
220}
221
222void gus_midi_interrupt(int dummy)
223{
224 volatile unsigned char stat, data;
225 int timeout = 10;
226
227 spin_lock(&gus_lock);
228
229 while (timeout-- > 0 && (stat = GUS_MIDI_STATUS()) & (MIDI_RCV_FULL | MIDI_XMIT_EMPTY))
230 {
231 if (stat & MIDI_RCV_FULL)
232 {
233 data = inb(u_MidiData);
234 if (input_opened)
235 midi_input_intr(my_dev, data);
236 }
237 if (stat & MIDI_XMIT_EMPTY)
238 {
239 while (qlen && dump_to_midi(tmp_queue[qhead]))
240 {
241 qlen--;
242 qhead++;
243 }
244 if (!qlen)
245 {
246 /*
247 * Disable Midi output interrupts, since no data in the buffer
248 */
249 gus_midi_control &= ~MIDI_ENABLE_XMIT;
250 outb((gus_midi_control), u_MidiControl);
251 outb((gus_midi_control), u_MidiControl);
252 }
253 }
254 }
255 spin_unlock(&gus_lock);
256}