Commit | Line | Data |
---|---|---|
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) | |
76439c2a AB |
89 | wait_event_interruptible_timeout(midi_sleeper[dev], |
90 | !midi_devs[dev]->buffer_status(dev), HZ/10); | |
1da177e4 LT |
91 | } |
92 | ||
93 | static void midi_input_intr(int dev, unsigned char data) | |
94 | { | |
95 | if (midi_in_buf[dev] == NULL) | |
96 | return; | |
97 | ||
98 | if (data == 0xfe) /* | |
99 | * Active sensing | |
100 | */ | |
101 | return; /* | |
102 | * Ignore | |
103 | */ | |
104 | ||
105 | if (SPACE_AVAIL(midi_in_buf[dev])) { | |
106 | QUEUE_BYTE(midi_in_buf[dev], data); | |
107 | wake_up(&input_sleeper[dev]); | |
108 | } | |
109 | } | |
110 | ||
111 | static void midi_output_intr(int dev) | |
112 | { | |
113 | /* | |
114 | * Currently NOP | |
115 | */ | |
116 | } | |
117 | ||
118 | static void midi_poll(unsigned long dummy) | |
119 | { | |
120 | unsigned long flags; | |
121 | int dev; | |
122 | ||
123 | spin_lock_irqsave(&lock, flags); | |
124 | if (open_devs) | |
125 | { | |
126 | for (dev = 0; dev < num_midis; dev++) | |
127 | if (midi_devs[dev] != NULL && midi_out_buf[dev] != NULL) | |
128 | { | |
5e8e7c38 | 129 | while (DATA_AVAIL(midi_out_buf[dev])) |
1da177e4 | 130 | { |
5e8e7c38 | 131 | int ok; |
1da177e4 LT |
132 | int c = midi_out_buf[dev]->queue[midi_out_buf[dev]->head]; |
133 | ||
134 | spin_unlock_irqrestore(&lock,flags);/* Give some time to others */ | |
135 | ok = midi_devs[dev]->outputc(dev, c); | |
136 | spin_lock_irqsave(&lock, flags); | |
5e8e7c38 CL |
137 | if (!ok) |
138 | break; | |
1da177e4 LT |
139 | midi_out_buf[dev]->head = (midi_out_buf[dev]->head + 1) % MAX_QUEUE_SIZE; |
140 | midi_out_buf[dev]->len--; | |
141 | } | |
142 | ||
143 | if (DATA_AVAIL(midi_out_buf[dev]) < 100) | |
144 | wake_up(&midi_sleeper[dev]); | |
145 | } | |
146 | poll_timer.expires = (1) + jiffies; | |
147 | add_timer(&poll_timer); | |
148 | /* | |
149 | * Come back later | |
150 | */ | |
151 | } | |
152 | spin_unlock_irqrestore(&lock, flags); | |
153 | } | |
154 | ||
155 | int MIDIbuf_open(int dev, struct file *file) | |
156 | { | |
157 | int mode, err; | |
158 | ||
159 | dev = dev >> 4; | |
160 | mode = translate_mode(file); | |
161 | ||
162 | if (num_midis > MAX_MIDI_DEV) | |
163 | { | |
164 | printk(KERN_ERR "midi: Too many midi interfaces\n"); | |
165 | num_midis = MAX_MIDI_DEV; | |
166 | } | |
167 | if (dev < 0 || dev >= num_midis || midi_devs[dev] == NULL) | |
168 | return -ENXIO; | |
169 | /* | |
170 | * Interrupts disabled. Be careful | |
171 | */ | |
172 | ||
173 | module_put(midi_devs[dev]->owner); | |
174 | ||
175 | if ((err = midi_devs[dev]->open(dev, mode, | |
176 | midi_input_intr, midi_output_intr)) < 0) | |
177 | return err; | |
178 | ||
179 | parms[dev].prech_timeout = MAX_SCHEDULE_TIMEOUT; | |
ea7dd251 | 180 | midi_in_buf[dev] = vmalloc(sizeof(struct midi_buf)); |
1da177e4 LT |
181 | |
182 | if (midi_in_buf[dev] == NULL) | |
183 | { | |
184 | printk(KERN_WARNING "midi: Can't allocate buffer\n"); | |
185 | midi_devs[dev]->close(dev); | |
186 | return -EIO; | |
187 | } | |
188 | midi_in_buf[dev]->len = midi_in_buf[dev]->head = midi_in_buf[dev]->tail = 0; | |
189 | ||
ea7dd251 | 190 | midi_out_buf[dev] = vmalloc(sizeof(struct midi_buf)); |
1da177e4 LT |
191 | |
192 | if (midi_out_buf[dev] == NULL) | |
193 | { | |
194 | printk(KERN_WARNING "midi: Can't allocate buffer\n"); | |
195 | midi_devs[dev]->close(dev); | |
196 | vfree(midi_in_buf[dev]); | |
197 | midi_in_buf[dev] = NULL; | |
198 | return -EIO; | |
199 | } | |
200 | midi_out_buf[dev]->len = midi_out_buf[dev]->head = midi_out_buf[dev]->tail = 0; | |
201 | open_devs++; | |
202 | ||
203 | init_waitqueue_head(&midi_sleeper[dev]); | |
204 | init_waitqueue_head(&input_sleeper[dev]); | |
205 | ||
206 | if (open_devs < 2) /* This was first open */ | |
207 | { | |
208 | poll_timer.expires = 1 + jiffies; | |
209 | add_timer(&poll_timer); /* Start polling */ | |
210 | } | |
211 | return err; | |
212 | } | |
213 | ||
214 | void MIDIbuf_release(int dev, struct file *file) | |
215 | { | |
216 | int mode; | |
217 | ||
218 | dev = dev >> 4; | |
219 | mode = translate_mode(file); | |
220 | ||
221 | if (dev < 0 || dev >= num_midis || midi_devs[dev] == NULL) | |
222 | return; | |
223 | ||
224 | /* | |
225 | * Wait until the queue is empty | |
226 | */ | |
227 | ||
228 | if (mode != OPEN_READ) | |
229 | { | |
230 | midi_devs[dev]->outputc(dev, 0xfe); /* | |
231 | * Active sensing to shut the | |
232 | * devices | |
233 | */ | |
234 | ||
76439c2a AB |
235 | wait_event_interruptible(midi_sleeper[dev], |
236 | !DATA_AVAIL(midi_out_buf[dev])); | |
1da177e4 LT |
237 | /* |
238 | * Sync | |
239 | */ | |
240 | ||
241 | drain_midi_queue(dev); /* | |
242 | * Ensure the output queues are empty | |
243 | */ | |
244 | } | |
245 | ||
246 | midi_devs[dev]->close(dev); | |
247 | ||
248 | open_devs--; | |
249 | if (open_devs == 0) | |
250 | del_timer_sync(&poll_timer); | |
251 | vfree(midi_in_buf[dev]); | |
252 | vfree(midi_out_buf[dev]); | |
253 | midi_in_buf[dev] = NULL; | |
254 | midi_out_buf[dev] = NULL; | |
255 | ||
256 | module_put(midi_devs[dev]->owner); | |
257 | } | |
258 | ||
259 | int MIDIbuf_write(int dev, struct file *file, const char __user *buf, int count) | |
260 | { | |
261 | int c, n, i; | |
262 | unsigned char tmp_data; | |
263 | ||
264 | dev = dev >> 4; | |
265 | ||
266 | if (!count) | |
267 | return 0; | |
268 | ||
269 | c = 0; | |
270 | ||
271 | while (c < count) | |
272 | { | |
273 | n = SPACE_AVAIL(midi_out_buf[dev]); | |
274 | ||
275 | if (n == 0) { /* | |
276 | * No space just now. | |
277 | */ | |
278 | ||
279 | if (file->f_flags & O_NONBLOCK) { | |
280 | c = -EAGAIN; | |
281 | goto out; | |
282 | } | |
283 | ||
76439c2a AB |
284 | if (wait_event_interruptible(midi_sleeper[dev], |
285 | SPACE_AVAIL(midi_out_buf[dev]))) | |
1da177e4 LT |
286 | { |
287 | c = -EINTR; | |
288 | goto out; | |
289 | } | |
290 | n = SPACE_AVAIL(midi_out_buf[dev]); | |
291 | } | |
292 | if (n > (count - c)) | |
293 | n = count - c; | |
294 | ||
295 | for (i = 0; i < n; i++) | |
296 | { | |
25985edc | 297 | /* BROKE BROKE BROKE - CAN'T DO THIS WITH CLI !! */ |
1da177e4 LT |
298 | /* yes, think the same, so I removed the cli() brackets |
299 | QUEUE_BYTE is protected against interrupts */ | |
300 | if (copy_from_user((char *) &tmp_data, &(buf)[c], 1)) { | |
301 | c = -EFAULT; | |
302 | goto out; | |
303 | } | |
304 | QUEUE_BYTE(midi_out_buf[dev], tmp_data); | |
305 | c++; | |
306 | } | |
307 | } | |
308 | out: | |
309 | return c; | |
310 | } | |
311 | ||
312 | ||
313 | int MIDIbuf_read(int dev, struct file *file, char __user *buf, int count) | |
314 | { | |
315 | int n, c = 0; | |
316 | unsigned char tmp_data; | |
317 | ||
318 | dev = dev >> 4; | |
319 | ||
320 | if (!DATA_AVAIL(midi_in_buf[dev])) { /* | |
321 | * No data yet, wait | |
322 | */ | |
323 | if (file->f_flags & O_NONBLOCK) { | |
324 | c = -EAGAIN; | |
325 | goto out; | |
326 | } | |
76439c2a AB |
327 | wait_event_interruptible_timeout(input_sleeper[dev], |
328 | DATA_AVAIL(midi_in_buf[dev]), | |
329 | parms[dev].prech_timeout); | |
1da177e4 LT |
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 |