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Commit | Line | Data |
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1da177e4 | 1 | /* |
f30c2269 | 2 | * sound/oss/midibuf.c |
1da177e4 LT |
3 | * |
4 | * Device file manager for /dev/midi# | |
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 | /* | |
14 | * Thomas Sailer : ioctl code reworked (vmalloc/vfree removed) | |
15 | */ | |
16 | #include <linux/stddef.h> | |
17 | #include <linux/kmod.h> | |
18 | #include <linux/spinlock.h> | |
19 | #define MIDIBUF_C | |
20 | ||
21 | #include "sound_config.h" | |
22 | ||
23 | ||
24 | /* | |
25 | * Don't make MAX_QUEUE_SIZE larger than 4000 | |
26 | */ | |
27 | ||
28 | #define MAX_QUEUE_SIZE 4000 | |
29 | ||
30 | static wait_queue_head_t midi_sleeper[MAX_MIDI_DEV]; | |
31 | static wait_queue_head_t input_sleeper[MAX_MIDI_DEV]; | |
32 | ||
33 | struct midi_buf | |
34 | { | |
35 | int len, head, tail; | |
36 | unsigned char queue[MAX_QUEUE_SIZE]; | |
37 | }; | |
38 | ||
39 | struct midi_parms | |
40 | { | |
41 | long prech_timeout; /* | |
42 | * Timeout before the first ch | |
43 | */ | |
44 | }; | |
45 | ||
46 | static struct midi_buf *midi_out_buf[MAX_MIDI_DEV] = {NULL}; | |
47 | static struct midi_buf *midi_in_buf[MAX_MIDI_DEV] = {NULL}; | |
48 | static struct midi_parms parms[MAX_MIDI_DEV]; | |
49 | ||
50 | static void midi_poll(unsigned long dummy); | |
51 | ||
52 | ||
8d06afab | 53 | static DEFINE_TIMER(poll_timer, midi_poll, 0, 0); |
1da177e4 LT |
54 | |
55 | static volatile int open_devs; | |
56 | static DEFINE_SPINLOCK(lock); | |
57 | ||
58 | #define DATA_AVAIL(q) (q->len) | |
59 | #define SPACE_AVAIL(q) (MAX_QUEUE_SIZE - q->len) | |
60 | ||
61 | #define QUEUE_BYTE(q, data) \ | |
62 | if (SPACE_AVAIL(q)) \ | |
63 | { \ | |
64 | unsigned long flags; \ | |
65 | spin_lock_irqsave(&lock, flags); \ | |
66 | q->queue[q->tail] = (data); \ | |
67 | q->len++; q->tail = (q->tail+1) % MAX_QUEUE_SIZE; \ | |
68 | spin_unlock_irqrestore(&lock, flags); \ | |
69 | } | |
70 | ||
71 | #define REMOVE_BYTE(q, data) \ | |
72 | if (DATA_AVAIL(q)) \ | |
73 | { \ | |
74 | unsigned long flags; \ | |
75 | spin_lock_irqsave(&lock, flags); \ | |
76 | data = q->queue[q->head]; \ | |
77 | q->len--; q->head = (q->head+1) % MAX_QUEUE_SIZE; \ | |
78 | spin_unlock_irqrestore(&lock, flags); \ | |
79 | } | |
80 | ||
81 | static void drain_midi_queue(int dev) | |
82 | { | |
83 | ||
84 | /* | |
85 | * Give the Midi driver time to drain its output queues | |
86 | */ | |
87 | ||
88 | if (midi_devs[dev]->buffer_status != NULL) | |
89 | while (!signal_pending(current) && midi_devs[dev]->buffer_status(dev)) | |
90 | interruptible_sleep_on_timeout(&midi_sleeper[dev], | |
91 | HZ/10); | |
92 | } | |
93 | ||
94 | static void midi_input_intr(int dev, unsigned char data) | |
95 | { | |
96 | if (midi_in_buf[dev] == NULL) | |
97 | return; | |
98 | ||
99 | if (data == 0xfe) /* | |
100 | * Active sensing | |
101 | */ | |
102 | return; /* | |
103 | * Ignore | |
104 | */ | |
105 | ||
106 | if (SPACE_AVAIL(midi_in_buf[dev])) { | |
107 | QUEUE_BYTE(midi_in_buf[dev], data); | |
108 | wake_up(&input_sleeper[dev]); | |
109 | } | |
110 | } | |
111 | ||
112 | static void midi_output_intr(int dev) | |
113 | { | |
114 | /* | |
115 | * Currently NOP | |
116 | */ | |
117 | } | |
118 | ||
119 | static void midi_poll(unsigned long dummy) | |
120 | { | |
121 | unsigned long flags; | |
122 | int dev; | |
123 | ||
124 | spin_lock_irqsave(&lock, flags); | |
125 | if (open_devs) | |
126 | { | |
127 | for (dev = 0; dev < num_midis; dev++) | |
128 | if (midi_devs[dev] != NULL && midi_out_buf[dev] != NULL) | |
129 | { | |
5e8e7c38 | 130 | while (DATA_AVAIL(midi_out_buf[dev])) |
1da177e4 | 131 | { |
5e8e7c38 | 132 | int ok; |
1da177e4 LT |
133 | int c = midi_out_buf[dev]->queue[midi_out_buf[dev]->head]; |
134 | ||
135 | spin_unlock_irqrestore(&lock,flags);/* Give some time to others */ | |
136 | ok = midi_devs[dev]->outputc(dev, c); | |
137 | spin_lock_irqsave(&lock, flags); | |
5e8e7c38 CL |
138 | if (!ok) |
139 | break; | |
1da177e4 LT |
140 | midi_out_buf[dev]->head = (midi_out_buf[dev]->head + 1) % MAX_QUEUE_SIZE; |
141 | midi_out_buf[dev]->len--; | |
142 | } | |
143 | ||
144 | if (DATA_AVAIL(midi_out_buf[dev]) < 100) | |
145 | wake_up(&midi_sleeper[dev]); | |
146 | } | |
147 | poll_timer.expires = (1) + jiffies; | |
148 | add_timer(&poll_timer); | |
149 | /* | |
150 | * Come back later | |
151 | */ | |
152 | } | |
153 | spin_unlock_irqrestore(&lock, flags); | |
154 | } | |
155 | ||
156 | int MIDIbuf_open(int dev, struct file *file) | |
157 | { | |
158 | int mode, err; | |
159 | ||
160 | dev = dev >> 4; | |
161 | mode = translate_mode(file); | |
162 | ||
163 | if (num_midis > MAX_MIDI_DEV) | |
164 | { | |
165 | printk(KERN_ERR "midi: Too many midi interfaces\n"); | |
166 | num_midis = MAX_MIDI_DEV; | |
167 | } | |
168 | if (dev < 0 || dev >= num_midis || midi_devs[dev] == NULL) | |
169 | return -ENXIO; | |
170 | /* | |
171 | * Interrupts disabled. Be careful | |
172 | */ | |
173 | ||
174 | module_put(midi_devs[dev]->owner); | |
175 | ||
176 | if ((err = midi_devs[dev]->open(dev, mode, | |
177 | midi_input_intr, midi_output_intr)) < 0) | |
178 | return err; | |
179 | ||
180 | parms[dev].prech_timeout = MAX_SCHEDULE_TIMEOUT; | |
ea7dd251 | 181 | midi_in_buf[dev] = vmalloc(sizeof(struct midi_buf)); |
1da177e4 LT |
182 | |
183 | if (midi_in_buf[dev] == NULL) | |
184 | { | |
185 | printk(KERN_WARNING "midi: Can't allocate buffer\n"); | |
186 | midi_devs[dev]->close(dev); | |
187 | return -EIO; | |
188 | } | |
189 | midi_in_buf[dev]->len = midi_in_buf[dev]->head = midi_in_buf[dev]->tail = 0; | |
190 | ||
ea7dd251 | 191 | midi_out_buf[dev] = vmalloc(sizeof(struct midi_buf)); |
1da177e4 LT |
192 | |
193 | if (midi_out_buf[dev] == NULL) | |
194 | { | |
195 | printk(KERN_WARNING "midi: Can't allocate buffer\n"); | |
196 | midi_devs[dev]->close(dev); | |
197 | vfree(midi_in_buf[dev]); | |
198 | midi_in_buf[dev] = NULL; | |
199 | return -EIO; | |
200 | } | |
201 | midi_out_buf[dev]->len = midi_out_buf[dev]->head = midi_out_buf[dev]->tail = 0; | |
202 | open_devs++; | |
203 | ||
204 | init_waitqueue_head(&midi_sleeper[dev]); | |
205 | init_waitqueue_head(&input_sleeper[dev]); | |
206 | ||
207 | if (open_devs < 2) /* This was first open */ | |
208 | { | |
209 | poll_timer.expires = 1 + jiffies; | |
210 | add_timer(&poll_timer); /* Start polling */ | |
211 | } | |
212 | return err; | |
213 | } | |
214 | ||
215 | void MIDIbuf_release(int dev, struct file *file) | |
216 | { | |
217 | int mode; | |
218 | ||
219 | dev = dev >> 4; | |
220 | mode = translate_mode(file); | |
221 | ||
222 | if (dev < 0 || dev >= num_midis || midi_devs[dev] == NULL) | |
223 | return; | |
224 | ||
225 | /* | |
226 | * Wait until the queue is empty | |
227 | */ | |
228 | ||
229 | if (mode != OPEN_READ) | |
230 | { | |
231 | midi_devs[dev]->outputc(dev, 0xfe); /* | |
232 | * Active sensing to shut the | |
233 | * devices | |
234 | */ | |
235 | ||
236 | while (!signal_pending(current) && DATA_AVAIL(midi_out_buf[dev])) | |
237 | interruptible_sleep_on(&midi_sleeper[dev]); | |
238 | /* | |
239 | * Sync | |
240 | */ | |
241 | ||
242 | drain_midi_queue(dev); /* | |
243 | * Ensure the output queues are empty | |
244 | */ | |
245 | } | |
246 | ||
247 | midi_devs[dev]->close(dev); | |
248 | ||
249 | open_devs--; | |
250 | if (open_devs == 0) | |
251 | del_timer_sync(&poll_timer); | |
252 | vfree(midi_in_buf[dev]); | |
253 | vfree(midi_out_buf[dev]); | |
254 | midi_in_buf[dev] = NULL; | |
255 | midi_out_buf[dev] = NULL; | |
256 | ||
257 | module_put(midi_devs[dev]->owner); | |
258 | } | |
259 | ||
260 | int MIDIbuf_write(int dev, struct file *file, const char __user *buf, int count) | |
261 | { | |
262 | int c, n, i; | |
263 | unsigned char tmp_data; | |
264 | ||
265 | dev = dev >> 4; | |
266 | ||
267 | if (!count) | |
268 | return 0; | |
269 | ||
270 | c = 0; | |
271 | ||
272 | while (c < count) | |
273 | { | |
274 | n = SPACE_AVAIL(midi_out_buf[dev]); | |
275 | ||
276 | if (n == 0) { /* | |
277 | * No space just now. | |
278 | */ | |
279 | ||
280 | if (file->f_flags & O_NONBLOCK) { | |
281 | c = -EAGAIN; | |
282 | goto out; | |
283 | } | |
284 | ||
285 | interruptible_sleep_on(&midi_sleeper[dev]); | |
286 | if (signal_pending(current)) | |
287 | { | |
288 | c = -EINTR; | |
289 | goto out; | |
290 | } | |
291 | n = SPACE_AVAIL(midi_out_buf[dev]); | |
292 | } | |
293 | if (n > (count - c)) | |
294 | n = count - c; | |
295 | ||
296 | for (i = 0; i < n; i++) | |
297 | { | |
25985edc | 298 | /* BROKE BROKE BROKE - CAN'T DO THIS WITH CLI !! */ |
1da177e4 LT |
299 | /* yes, think the same, so I removed the cli() brackets |
300 | QUEUE_BYTE is protected against interrupts */ | |
301 | if (copy_from_user((char *) &tmp_data, &(buf)[c], 1)) { | |
302 | c = -EFAULT; | |
303 | goto out; | |
304 | } | |
305 | QUEUE_BYTE(midi_out_buf[dev], tmp_data); | |
306 | c++; | |
307 | } | |
308 | } | |
309 | out: | |
310 | return c; | |
311 | } | |
312 | ||
313 | ||
314 | int MIDIbuf_read(int dev, struct file *file, char __user *buf, int count) | |
315 | { | |
316 | int n, c = 0; | |
317 | unsigned char tmp_data; | |
318 | ||
319 | dev = dev >> 4; | |
320 | ||
321 | if (!DATA_AVAIL(midi_in_buf[dev])) { /* | |
322 | * No data yet, wait | |
323 | */ | |
324 | if (file->f_flags & O_NONBLOCK) { | |
325 | c = -EAGAIN; | |
326 | goto out; | |
327 | } | |
328 | interruptible_sleep_on_timeout(&input_sleeper[dev], | |
329 | parms[dev].prech_timeout); | |
330 | ||
331 | if (signal_pending(current)) | |
332 | c = -EINTR; /* The user is getting restless */ | |
333 | } | |
334 | if (c == 0 && DATA_AVAIL(midi_in_buf[dev])) /* | |
335 | * Got some bytes | |
336 | */ | |
337 | { | |
338 | n = DATA_AVAIL(midi_in_buf[dev]); | |
339 | if (n > count) | |
340 | n = count; | |
341 | c = 0; | |
342 | ||
343 | while (c < n) | |
344 | { | |
345 | char *fixit; | |
346 | REMOVE_BYTE(midi_in_buf[dev], tmp_data); | |
347 | fixit = (char *) &tmp_data; | |
348 | /* BROKE BROKE BROKE */ | |
349 | /* yes removed the cli() brackets again | |
350 | should q->len,tail&head be atomic_t? */ | |
351 | if (copy_to_user(&(buf)[c], fixit, 1)) { | |
352 | c = -EFAULT; | |
353 | goto out; | |
354 | } | |
355 | c++; | |
356 | } | |
357 | } | |
358 | out: | |
359 | return c; | |
360 | } | |
361 | ||
362 | int MIDIbuf_ioctl(int dev, struct file *file, | |
363 | unsigned int cmd, void __user *arg) | |
364 | { | |
365 | int val; | |
366 | ||
367 | dev = dev >> 4; | |
368 | ||
369 | if (((cmd >> 8) & 0xff) == 'C') | |
370 | { | |
371 | if (midi_devs[dev]->coproc) /* Coprocessor ioctl */ | |
372 | return midi_devs[dev]->coproc->ioctl(midi_devs[dev]->coproc->devc, cmd, arg, 0); | |
373 | /* printk("/dev/midi%d: No coprocessor for this device\n", dev);*/ | |
374 | return -ENXIO; | |
375 | } | |
376 | else | |
377 | { | |
378 | switch (cmd) | |
379 | { | |
380 | case SNDCTL_MIDI_PRETIME: | |
381 | if (get_user(val, (int __user *)arg)) | |
382 | return -EFAULT; | |
383 | if (val < 0) | |
384 | val = 0; | |
385 | val = (HZ * val) / 10; | |
386 | parms[dev].prech_timeout = val; | |
387 | return put_user(val, (int __user *)arg); | |
388 | ||
389 | default: | |
390 | if (!midi_devs[dev]->ioctl) | |
391 | return -EINVAL; | |
392 | return midi_devs[dev]->ioctl(dev, cmd, arg); | |
393 | } | |
394 | } | |
395 | } | |
396 | ||
397 | /* No kernel lock - fine */ | |
398 | unsigned int MIDIbuf_poll(int dev, struct file *file, poll_table * wait) | |
399 | { | |
400 | unsigned int mask = 0; | |
401 | ||
402 | dev = dev >> 4; | |
403 | ||
404 | /* input */ | |
405 | poll_wait(file, &input_sleeper[dev], wait); | |
406 | if (DATA_AVAIL(midi_in_buf[dev])) | |
407 | mask |= POLLIN | POLLRDNORM; | |
408 | ||
409 | /* output */ | |
410 | poll_wait(file, &midi_sleeper[dev], wait); | |
411 | if (!SPACE_AVAIL(midi_out_buf[dev])) | |
412 | mask |= POLLOUT | POLLWRNORM; | |
413 | ||
414 | return mask; | |
415 | } | |
416 | ||
417 | ||
1da177e4 LT |
418 | int MIDIbuf_avail(int dev) |
419 | { | |
420 | if (midi_in_buf[dev]) | |
421 | return DATA_AVAIL (midi_in_buf[dev]); | |
422 | return 0; | |
423 | } | |
ece7f77b AB |
424 | EXPORT_SYMBOL(MIDIbuf_avail); |
425 |