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1 | /* -*- linux-c -*- |
2 | * dtlk.c - DoubleTalk PC driver for Linux |
3 | * |
4 | * Original author: Chris Pallotta <chris@allmedia.com> |
5 | * Current maintainer: Jim Van Zandt <jrv@vanzandt.mv.com> |
6 | * |
7 | * 2000-03-18 Jim Van Zandt: Fix polling. |
8 | * Eliminate dtlk_timer_active flag and separate dtlk_stop_timer |
9 | * function. Don't restart timer in dtlk_timer_tick. Restart timer |
10 | * in dtlk_poll after every poll. dtlk_poll returns mask (duh). |
11 | * Eliminate unused function dtlk_write_byte. Misc. code cleanups. |
12 | */ |
13 | |
14 | /* This driver is for the DoubleTalk PC, a speech synthesizer |
15 | manufactured by RC Systems (http://www.rcsys.com/). It was written |
16 | based on documentation in their User's Manual file and Developer's |
17 | Tools disk. |
18 | |
19 | The DoubleTalk PC contains four voice synthesizers: text-to-speech |
20 | (TTS), linear predictive coding (LPC), PCM/ADPCM, and CVSD. It |
21 | also has a tone generator. Output data for LPC are written to the |
22 | LPC port, and output data for the other modes are written to the |
23 | TTS port. |
24 | |
25 | Two kinds of data can be read from the DoubleTalk: status |
26 | information (in response to the "\001?" interrogation command) is |
27 | read from the TTS port, and index markers (which mark the progress |
28 | of the speech) are read from the LPC port. Not all models of the |
29 | DoubleTalk PC implement index markers. Both the TTS and LPC ports |
30 | can also display status flags. |
31 | |
32 | The DoubleTalk PC generates no interrupts. |
33 | |
34 | These characteristics are mapped into the Unix stream I/O model as |
35 | follows: |
36 | |
37 | "write" sends bytes to the TTS port. It is the responsibility of |
38 | the user program to switch modes among TTS, PCM/ADPCM, and CVSD. |
39 | This driver was written for use with the text-to-speech |
40 | synthesizer. If LPC output is needed some day, other minor device |
41 | numbers can be used to select among output modes. |
42 | |
43 | "read" gets index markers from the LPC port. If the device does |
44 | not implement index markers, the read will fail with error EINVAL. |
45 | |
46 | Status information is available using the DTLK_INTERROGATE ioctl. |
47 | |
48 | */ |
49 | |
50 | #include <linux/module.h> |
51 | |
52 | #define KERNEL |
53 | #include <linux/types.h> |
54 | #include <linux/fs.h> |
55 | #include <linux/mm.h> |
56 | #include <linux/errno.h> /* for -EBUSY */ |
57 | #include <linux/ioport.h> /* for request_region */ |
58 | #include <linux/delay.h> /* for loops_per_jiffy */ |
59 | #include <linux/sched.h> |
60 | #include <linux/smp_lock.h> /* cycle_kernel_lock() */ |
61 | #include <asm/io.h> /* for inb_p, outb_p, inb, outb, etc. */ |
62 | #include <asm/uaccess.h> /* for get_user, etc. */ |
63 | #include <linux/wait.h> /* for wait_queue */ |
64 | #include <linux/init.h> /* for __init, module_{init,exit} */ |
65 | #include <linux/poll.h> /* for POLLIN, etc. */ |
66 | #include <linux/dtlk.h> /* local header file for DoubleTalk values */ |
67 | |
68 | #ifdef TRACING |
69 | #define TRACE_TEXT(str) printk(str); |
70 | #define TRACE_RET printk(")") |
71 | #else /* !TRACING */ |
72 | #define TRACE_TEXT(str) ((void) 0) |
73 | #define TRACE_RET ((void) 0) |
74 | #endif /* TRACING */ |
75 | |
76 | static void dtlk_timer_tick(unsigned long data); |
77 | |
78 | static int dtlk_major; |
79 | static int dtlk_port_lpc; |
80 | static int dtlk_port_tts; |
81 | static int dtlk_busy; |
82 | static int dtlk_has_indexing; |
83 | static unsigned int dtlk_portlist[] = |
84 | {0x25e, 0x29e, 0x2de, 0x31e, 0x35e, 0x39e, 0}; |
85 | static wait_queue_head_t dtlk_process_list; |
86 | static DEFINE_TIMER(dtlk_timer, dtlk_timer_tick, 0, 0); |
87 | |
88 | /* prototypes for file_operations struct */ |
89 | static ssize_t dtlk_read(struct file *, char __user *, |
90 | size_t nbytes, loff_t * ppos); |
91 | static ssize_t dtlk_write(struct file *, const char __user *, |
92 | size_t nbytes, loff_t * ppos); |
93 | static unsigned int dtlk_poll(struct file *, poll_table *); |
94 | static int dtlk_open(struct inode *, struct file *); |
95 | static int dtlk_release(struct inode *, struct file *); |
96 | static int dtlk_ioctl(struct inode *inode, struct file *file, |
97 | unsigned int cmd, unsigned long arg); |
98 | |
99 | static const struct file_operations dtlk_fops = |
100 | { |
101 | .owner = THIS_MODULE, |
102 | .read = dtlk_read, |
103 | .write = dtlk_write, |
104 | .poll = dtlk_poll, |
105 | .ioctl = dtlk_ioctl, |
106 | .open = dtlk_open, |
107 | .release = dtlk_release, |
108 | }; |
109 | |
110 | /* local prototypes */ |
111 | static int dtlk_dev_probe(void); |
112 | static struct dtlk_settings *dtlk_interrogate(void); |
113 | static int dtlk_readable(void); |
114 | static char dtlk_read_lpc(void); |
115 | static char dtlk_read_tts(void); |
116 | static int dtlk_writeable(void); |
117 | static char dtlk_write_bytes(const char *buf, int n); |
118 | static char dtlk_write_tts(char); |
119 | /* |
120 | static void dtlk_handle_error(char, char, unsigned int); |
121 | */ |
122 | |
123 | static ssize_t dtlk_read(struct file *file, char __user *buf, |
124 | size_t count, loff_t * ppos) |
125 | { |
126 | unsigned int minor = iminor(file->f_path.dentry->d_inode); |
127 | char ch; |
128 | int i = 0, retries; |
129 | |
130 | TRACE_TEXT("(dtlk_read"); |
131 | /* printk("DoubleTalk PC - dtlk_read()\n"); */ |
132 | |
133 | if (minor != DTLK_MINOR || !dtlk_has_indexing) |
134 | return -EINVAL; |
135 | |
136 | for (retries = 0; retries < loops_per_jiffy; retries++) { |
137 | while (i < count && dtlk_readable()) { |
138 | ch = dtlk_read_lpc(); |
139 | /* printk("dtlk_read() reads 0x%02x\n", ch); */ |
140 | if (put_user(ch, buf++)) |
141 | return -EFAULT; |
142 | i++; |
143 | } |
144 | if (i) |
145 | return i; |
146 | if (file->f_flags & O_NONBLOCK) |
147 | break; |
148 | msleep_interruptible(100); |
149 | } |
150 | if (retries == loops_per_jiffy) |
151 | printk(KERN_ERR "dtlk_read times out\n"); |
152 | TRACE_RET; |
153 | return -EAGAIN; |
154 | } |
155 | |
156 | static ssize_t dtlk_write(struct file *file, const char __user *buf, |
157 | size_t count, loff_t * ppos) |
158 | { |
159 | int i = 0, retries = 0, ch; |
160 | |
161 | TRACE_TEXT("(dtlk_write"); |
162 | #ifdef TRACING |
163 | printk(" \""); |
164 | { |
165 | int i, ch; |
166 | for (i = 0; i < count; i++) { |
167 | if (get_user(ch, buf + i)) |
168 | return -EFAULT; |
169 | if (' ' <= ch && ch <= '~') |
170 | printk("%c", ch); |
171 | else |
172 | printk("\\%03o", ch); |
173 | } |
174 | printk("\""); |
175 | } |
176 | #endif |
177 | |
178 | if (iminor(file->f_path.dentry->d_inode) != DTLK_MINOR) |
179 | return -EINVAL; |
180 | |
181 | while (1) { |
182 | while (i < count && !get_user(ch, buf) && |
183 | (ch == DTLK_CLEAR || dtlk_writeable())) { |
184 | dtlk_write_tts(ch); |
185 | buf++; |
186 | i++; |
187 | if (i % 5 == 0) |
188 | /* We yield our time until scheduled |
189 | again. This reduces the transfer |
190 | rate to 500 bytes/sec, but that's |
191 | still enough to keep up with the |
192 | speech synthesizer. */ |
193 | msleep_interruptible(1); |
194 | else { |
195 | /* the RDY bit goes zero 2-3 usec |
196 | after writing, and goes 1 again |
197 | 180-190 usec later. Here, we wait |
198 | up to 250 usec for the RDY bit to |
199 | go nonzero. */ |
200 | for (retries = 0; |
201 | retries < loops_per_jiffy / (4000/HZ); |
202 | retries++) |
203 | if (inb_p(dtlk_port_tts) & |
204 | TTS_WRITABLE) |
205 | break; |
206 | } |
207 | retries = 0; |
208 | } |
209 | if (i == count) |
210 | return i; |
211 | if (file->f_flags & O_NONBLOCK) |
212 | break; |
213 | |
214 | msleep_interruptible(1); |
215 | |
216 | if (++retries > 10 * HZ) { /* wait no more than 10 sec |
217 | from last write */ |
218 | printk("dtlk: write timeout. " |
219 | "inb_p(dtlk_port_tts) = 0x%02x\n", |
220 | inb_p(dtlk_port_tts)); |
221 | TRACE_RET; |
222 | return -EBUSY; |
223 | } |
224 | } |
225 | TRACE_RET; |
226 | return -EAGAIN; |
227 | } |
228 | |
229 | static unsigned int dtlk_poll(struct file *file, poll_table * wait) |
230 | { |
231 | int mask = 0; |
232 | unsigned long expires; |
233 | |
234 | TRACE_TEXT(" dtlk_poll"); |
235 | /* |
236 | static long int j; |
237 | printk("."); |
238 | printk("<%ld>", jiffies-j); |
239 | j=jiffies; |
240 | */ |
241 | poll_wait(file, &dtlk_process_list, wait); |
242 | |
243 | if (dtlk_has_indexing && dtlk_readable()) { |
244 | del_timer(&dtlk_timer); |
245 | mask = POLLIN | POLLRDNORM; |
246 | } |
247 | if (dtlk_writeable()) { |
248 | del_timer(&dtlk_timer); |
249 | mask |= POLLOUT | POLLWRNORM; |
250 | } |
251 | /* there are no exception conditions */ |
252 | |
253 | /* There won't be any interrupts, so we set a timer instead. */ |
254 | expires = jiffies + 3*HZ / 100; |
255 | mod_timer(&dtlk_timer, expires); |
256 | |
257 | return mask; |
258 | } |
259 | |
260 | static void dtlk_timer_tick(unsigned long data) |
261 | { |
262 | TRACE_TEXT(" dtlk_timer_tick"); |
263 | wake_up_interruptible(&dtlk_process_list); |
264 | } |
265 | |
266 | static int dtlk_ioctl(struct inode *inode, |
267 | struct file *file, |
268 | unsigned int cmd, |
269 | unsigned long arg) |
270 | { |
271 | char __user *argp = (char __user *)arg; |
272 | struct dtlk_settings *sp; |
273 | char portval; |
274 | TRACE_TEXT(" dtlk_ioctl"); |
275 | |
276 | switch (cmd) { |
277 | |
278 | case DTLK_INTERROGATE: |
279 | sp = dtlk_interrogate(); |
280 | if (copy_to_user(argp, sp, sizeof(struct dtlk_settings))) |
281 | return -EINVAL; |
282 | return 0; |
283 | |
284 | case DTLK_STATUS: |
285 | portval = inb_p(dtlk_port_tts); |
286 | return put_user(portval, argp); |
287 | |
288 | default: |
289 | return -EINVAL; |
290 | } |
291 | } |
292 | |
293 | /* Note that nobody ever sets dtlk_busy... */ |
294 | static int dtlk_open(struct inode *inode, struct file *file) |
295 | { |
296 | TRACE_TEXT("(dtlk_open"); |
297 | |
298 | cycle_kernel_lock(); |
299 | nonseekable_open(inode, file); |
300 | switch (iminor(inode)) { |
301 | case DTLK_MINOR: |
302 | if (dtlk_busy) |
303 | return -EBUSY; |
304 | return nonseekable_open(inode, file); |
305 | |
306 | default: |
307 | return -ENXIO; |
308 | } |
309 | } |
310 | |
311 | static int dtlk_release(struct inode *inode, struct file *file) |
312 | { |
313 | TRACE_TEXT("(dtlk_release"); |
314 | |
315 | switch (iminor(inode)) { |
316 | case DTLK_MINOR: |
317 | break; |
318 | |
319 | default: |
320 | break; |
321 | } |
322 | TRACE_RET; |
323 | |
324 | del_timer_sync(&dtlk_timer); |
325 | |
326 | return 0; |
327 | } |
328 | |
329 | static int __init dtlk_init(void) |
330 | { |
331 | int err; |
332 | |
333 | dtlk_port_lpc = 0; |
334 | dtlk_port_tts = 0; |
335 | dtlk_busy = 0; |
336 | dtlk_major = register_chrdev(0, "dtlk", &dtlk_fops); |
337 | if (dtlk_major < 0) { |
338 | printk(KERN_ERR "DoubleTalk PC - cannot register device\n"); |
339 | return dtlk_major; |
340 | } |
341 | err = dtlk_dev_probe(); |
342 | if (err) { |
343 | unregister_chrdev(dtlk_major, "dtlk"); |
344 | return err; |
345 | } |
346 | printk(", MAJOR %d\n", dtlk_major); |
347 | |
348 | init_waitqueue_head(&dtlk_process_list); |
349 | |
350 | return 0; |
351 | } |
352 | |
353 | static void __exit dtlk_cleanup (void) |
354 | { |
355 | dtlk_write_bytes("goodbye", 8); |
356 | msleep_interruptible(500); /* nap 0.50 sec but |
357 | could be awakened |
358 | earlier by |
359 | signals... */ |
360 | |
361 | dtlk_write_tts(DTLK_CLEAR); |
362 | unregister_chrdev(dtlk_major, "dtlk"); |
363 | release_region(dtlk_port_lpc, DTLK_IO_EXTENT); |
364 | } |
365 | |
366 | module_init(dtlk_init); |
367 | module_exit(dtlk_cleanup); |
368 | |
369 | /* ------------------------------------------------------------------------ */ |
370 | |
371 | static int dtlk_readable(void) |
372 | { |
373 | #ifdef TRACING |
374 | printk(" dtlk_readable=%u@%u", inb_p(dtlk_port_lpc) != 0x7f, jiffies); |
375 | #endif |
376 | return inb_p(dtlk_port_lpc) != 0x7f; |
377 | } |
378 | |
379 | static int dtlk_writeable(void) |
380 | { |
381 | /* TRACE_TEXT(" dtlk_writeable"); */ |
382 | #ifdef TRACINGMORE |
383 | printk(" dtlk_writeable=%u", (inb_p(dtlk_port_tts) & TTS_WRITABLE)!=0); |
384 | #endif |
385 | return inb_p(dtlk_port_tts) & TTS_WRITABLE; |
386 | } |
387 | |
388 | static int __init dtlk_dev_probe(void) |
389 | { |
390 | unsigned int testval = 0; |
391 | int i = 0; |
392 | struct dtlk_settings *sp; |
393 | |
394 | if (dtlk_port_lpc | dtlk_port_tts) |
395 | return -EBUSY; |
396 | |
397 | for (i = 0; dtlk_portlist[i]; i++) { |
398 | #if 0 |
399 | printk("DoubleTalk PC - Port %03x = %04x\n", |
400 | dtlk_portlist[i], (testval = inw_p(dtlk_portlist[i]))); |
401 | #endif |
402 | |
403 | if (!request_region(dtlk_portlist[i], DTLK_IO_EXTENT, |
404 | "dtlk")) |
405 | continue; |
406 | testval = inw_p(dtlk_portlist[i]); |
407 | if ((testval &= 0xfbff) == 0x107f) { |
408 | dtlk_port_lpc = dtlk_portlist[i]; |
409 | dtlk_port_tts = dtlk_port_lpc + 1; |
410 | |
411 | sp = dtlk_interrogate(); |
412 | printk("DoubleTalk PC at %03x-%03x, " |
413 | "ROM version %s, serial number %u", |
414 | dtlk_portlist[i], dtlk_portlist[i] + |
415 | DTLK_IO_EXTENT - 1, |
416 | sp->rom_version, sp->serial_number); |
417 | |
418 | /* put LPC port into known state, so |
419 | dtlk_readable() gives valid result */ |
420 | outb_p(0xff, dtlk_port_lpc); |
421 | |
422 | /* INIT string and index marker */ |
423 | dtlk_write_bytes("\036\1@\0\0012I\r", 8); |
424 | /* posting an index takes 18 msec. Here, we |
425 | wait up to 100 msec to see whether it |
426 | appears. */ |
427 | msleep_interruptible(100); |
428 | dtlk_has_indexing = dtlk_readable(); |
429 | #ifdef TRACING |
430 | printk(", indexing %d\n", dtlk_has_indexing); |
431 | #endif |
432 | #ifdef INSCOPE |
433 | { |
434 | /* This macro records ten samples read from the LPC port, for later display */ |
435 | #define LOOK \ |
436 | for (i = 0; i < 10; i++) \ |
437 | { \ |
438 | buffer[b++] = inb_p(dtlk_port_lpc); \ |
439 | __delay(loops_per_jiffy/(1000000/HZ)); \ |
440 | } |
441 | char buffer[1000]; |
442 | int b = 0, i, j; |
443 | |
444 | LOOK |
445 | outb_p(0xff, dtlk_port_lpc); |
446 | buffer[b++] = 0; |
447 | LOOK |
448 | dtlk_write_bytes("\0012I\r", 4); |
449 | buffer[b++] = 0; |
450 | __delay(50 * loops_per_jiffy / (1000/HZ)); |
451 | outb_p(0xff, dtlk_port_lpc); |
452 | buffer[b++] = 0; |
453 | LOOK |
454 | |
455 | printk("\n"); |
456 | for (j = 0; j < b; j++) |
457 | printk(" %02x", buffer[j]); |
458 | printk("\n"); |
459 | } |
460 | #endif /* INSCOPE */ |
461 | |
462 | #ifdef OUTSCOPE |
463 | { |
464 | /* This macro records ten samples read from the TTS port, for later display */ |
465 | #define LOOK \ |
466 | for (i = 0; i < 10; i++) \ |
467 | { \ |
468 | buffer[b++] = inb_p(dtlk_port_tts); \ |
469 | __delay(loops_per_jiffy/(1000000/HZ)); /* 1 us */ \ |
470 | } |
471 | char buffer[1000]; |
472 | int b = 0, i, j; |
473 | |
474 | mdelay(10); /* 10 ms */ |
475 | LOOK |
476 | outb_p(0x03, dtlk_port_tts); |
477 | buffer[b++] = 0; |
478 | LOOK |
479 | LOOK |
480 | |
481 | printk("\n"); |
482 | for (j = 0; j < b; j++) |
483 | printk(" %02x", buffer[j]); |
484 | printk("\n"); |
485 | } |
486 | #endif /* OUTSCOPE */ |
487 | |
488 | dtlk_write_bytes("Double Talk found", 18); |
489 | |
490 | return 0; |
491 | } |
492 | release_region(dtlk_portlist[i], DTLK_IO_EXTENT); |
493 | } |
494 | |
495 | printk(KERN_INFO "DoubleTalk PC - not found\n"); |
496 | return -ENODEV; |
497 | } |
498 | |
499 | /* |
500 | static void dtlk_handle_error(char op, char rc, unsigned int minor) |
501 | { |
502 | printk(KERN_INFO"\nDoubleTalk PC - MINOR: %d, OPCODE: %d, ERROR: %d\n", |
503 | minor, op, rc); |
504 | return; |
505 | } |
506 | */ |
507 | |
508 | /* interrogate the DoubleTalk PC and return its settings */ |
509 | static struct dtlk_settings *dtlk_interrogate(void) |
510 | { |
511 | unsigned char *t; |
512 | static char buf[sizeof(struct dtlk_settings) + 1]; |
513 | int total, i; |
514 | static struct dtlk_settings status; |
515 | TRACE_TEXT("(dtlk_interrogate"); |
516 | dtlk_write_bytes("\030\001?", 3); |
517 | for (total = 0, i = 0; i < 50; i++) { |
518 | buf[total] = dtlk_read_tts(); |
519 | if (total > 2 && buf[total] == 0x7f) |
520 | break; |
521 | if (total < sizeof(struct dtlk_settings)) |
522 | total++; |
523 | } |
524 | /* |
525 | if (i==50) printk("interrogate() read overrun\n"); |
526 | for (i=0; i<sizeof(buf); i++) |
527 | printk(" %02x", buf[i]); |
528 | printk("\n"); |
529 | */ |
530 | t = buf; |
531 | status.serial_number = t[0] + t[1] * 256; /* serial number is |
532 | little endian */ |
533 | t += 2; |
534 | |
535 | i = 0; |
536 | while (*t != '\r') { |
537 | status.rom_version[i] = *t; |
538 | if (i < sizeof(status.rom_version) - 1) |
539 | i++; |
540 | t++; |
541 | } |
542 | status.rom_version[i] = 0; |
543 | t++; |
544 | |
545 | status.mode = *t++; |
546 | status.punc_level = *t++; |
547 | status.formant_freq = *t++; |
548 | status.pitch = *t++; |
549 | status.speed = *t++; |
550 | status.volume = *t++; |
551 | status.tone = *t++; |
552 | status.expression = *t++; |
553 | status.ext_dict_loaded = *t++; |
554 | status.ext_dict_status = *t++; |
555 | status.free_ram = *t++; |
556 | status.articulation = *t++; |
557 | status.reverb = *t++; |
558 | status.eob = *t++; |
559 | status.has_indexing = dtlk_has_indexing; |
560 | TRACE_RET; |
561 | return &status; |
562 | } |
563 | |
564 | static char dtlk_read_tts(void) |
565 | { |
566 | int portval, retries = 0; |
567 | char ch; |
568 | TRACE_TEXT("(dtlk_read_tts"); |
569 | |
570 | /* verify DT is ready, read char, wait for ACK */ |
571 | do { |
572 | portval = inb_p(dtlk_port_tts); |
573 | } while ((portval & TTS_READABLE) == 0 && |
574 | retries++ < DTLK_MAX_RETRIES); |
575 | if (retries > DTLK_MAX_RETRIES) |
576 | printk(KERN_ERR "dtlk_read_tts() timeout\n"); |
577 | |
578 | ch = inb_p(dtlk_port_tts); /* input from TTS port */ |
579 | ch &= 0x7f; |
580 | outb_p(ch, dtlk_port_tts); |
581 | |
582 | retries = 0; |
583 | do { |
584 | portval = inb_p(dtlk_port_tts); |
585 | } while ((portval & TTS_READABLE) != 0 && |
586 | retries++ < DTLK_MAX_RETRIES); |
587 | if (retries > DTLK_MAX_RETRIES) |
588 | printk(KERN_ERR "dtlk_read_tts() timeout\n"); |
589 | |
590 | TRACE_RET; |
591 | return ch; |
592 | } |
593 | |
594 | static char dtlk_read_lpc(void) |
595 | { |
596 | int retries = 0; |
597 | char ch; |
598 | TRACE_TEXT("(dtlk_read_lpc"); |
599 | |
600 | /* no need to test -- this is only called when the port is readable */ |
601 | |
602 | ch = inb_p(dtlk_port_lpc); /* input from LPC port */ |
603 | |
604 | outb_p(0xff, dtlk_port_lpc); |
605 | |
606 | /* acknowledging a read takes 3-4 |
607 | usec. Here, we wait up to 20 usec |
608 | for the acknowledgement */ |
609 | retries = (loops_per_jiffy * 20) / (1000000/HZ); |
610 | while (inb_p(dtlk_port_lpc) != 0x7f && --retries > 0); |
611 | if (retries == 0) |
612 | printk(KERN_ERR "dtlk_read_lpc() timeout\n"); |
613 | |
614 | TRACE_RET; |
615 | return ch; |
616 | } |
617 | |
618 | /* write n bytes to tts port */ |
619 | static char dtlk_write_bytes(const char *buf, int n) |
620 | { |
621 | char val = 0; |
622 | /* printk("dtlk_write_bytes(\"%-*s\", %d)\n", n, buf, n); */ |
623 | TRACE_TEXT("(dtlk_write_bytes"); |
624 | while (n-- > 0) |
625 | val = dtlk_write_tts(*buf++); |
626 | TRACE_RET; |
627 | return val; |
628 | } |
629 | |
630 | static char dtlk_write_tts(char ch) |
631 | { |
632 | int retries = 0; |
633 | #ifdef TRACINGMORE |
634 | printk(" dtlk_write_tts("); |
635 | if (' ' <= ch && ch <= '~') |
636 | printk("'%c'", ch); |
637 | else |
638 | printk("0x%02x", ch); |
639 | #endif |
640 | if (ch != DTLK_CLEAR) /* no flow control for CLEAR command */ |
641 | while ((inb_p(dtlk_port_tts) & TTS_WRITABLE) == 0 && |
642 | retries++ < DTLK_MAX_RETRIES) /* DT ready? */ |
643 | ; |
644 | if (retries > DTLK_MAX_RETRIES) |
645 | printk(KERN_ERR "dtlk_write_tts() timeout\n"); |
646 | |
647 | outb_p(ch, dtlk_port_tts); /* output to TTS port */ |
648 | /* the RDY bit goes zero 2-3 usec after writing, and goes |
649 | 1 again 180-190 usec later. Here, we wait up to 10 |
650 | usec for the RDY bit to go zero. */ |
651 | for (retries = 0; retries < loops_per_jiffy / (100000/HZ); retries++) |
652 | if ((inb_p(dtlk_port_tts) & TTS_WRITABLE) == 0) |
653 | break; |
654 | |
655 | #ifdef TRACINGMORE |
656 | printk(")\n"); |
657 | #endif |
658 | return 0; |
659 | } |
660 | |
661 | MODULE_LICENSE("GPL"); |
662 |
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javiroman/ks7010
jz-2.6.34
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Tags:
od-2011-09-04
od-2011-09-18
v2.6.34-rc5
v2.6.34-rc6
v2.6.34-rc7
v3.9