xref: /linux/drivers/accessibility/speakup/synth.c (revision d53b8e36925256097a08d7cb749198d85cbf9b2b)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/types.h>
3 #include <linux/ctype.h>	/* for isdigit() and friends */
4 #include <linux/fs.h>
5 #include <linux/mm.h>		/* for verify_area */
6 #include <linux/errno.h>	/* for -EBUSY */
7 #include <linux/ioport.h>	/* for check_region, request_region */
8 #include <linux/interrupt.h>
9 #include <linux/delay.h>	/* for loops_per_sec */
10 #include <linux/kmod.h>
11 #include <linux/jiffies.h>
12 #include <linux/uaccess.h>	/* for copy_from_user */
13 #include <linux/sched.h>
14 #include <linux/timer.h>
15 #include <linux/kthread.h>
16 
17 #include "spk_priv.h"
18 #include "speakup.h"
19 #include "serialio.h"
20 
21 static LIST_HEAD(synths);
22 struct spk_synth *synth;
23 char spk_pitch_buff[32] = "";
24 static int module_status;
25 bool spk_quiet_boot;
26 
27 struct speakup_info_t speakup_info = {
28 	/*
29 	 * This spinlock is used to protect the entire speakup machinery, and
30 	 * must be taken at each kernel->speakup transition and released at
31 	 * each corresponding speakup->kernel transition.
32 	 *
33 	 * The progression thread only interferes with the speakup machinery
34 	 * through the synth buffer, so only needs to take the lock
35 	 * while tinkering with the buffer.
36 	 *
37 	 * We use spin_lock/trylock_irqsave and spin_unlock_irqrestore with this
38 	 * spinlock because speakup needs to disable the keyboard IRQ.
39 	 */
40 	.spinlock = __SPIN_LOCK_UNLOCKED(speakup_info.spinlock),
41 	.flushing = 0,
42 };
43 EXPORT_SYMBOL_GPL(speakup_info);
44 
45 static int do_synth_init(struct spk_synth *in_synth);
46 
47 /*
48  * Main loop of the progression thread: keep eating from the buffer
49  * and push to the serial port, waiting as needed
50  *
51  * For devices that have a "full" notification mechanism, the driver can
52  * adapt the loop the way they prefer.
53  */
54 static void _spk_do_catch_up(struct spk_synth *synth, int unicode)
55 {
56 	u16 ch;
57 	unsigned long flags;
58 	unsigned long jiff_max;
59 	struct var_t *delay_time;
60 	struct var_t *full_time;
61 	struct var_t *jiffy_delta;
62 	int jiffy_delta_val;
63 	int delay_time_val;
64 	int full_time_val;
65 	int ret;
66 
67 	jiffy_delta = spk_get_var(JIFFY);
68 	full_time = spk_get_var(FULL);
69 	delay_time = spk_get_var(DELAY);
70 
71 	spin_lock_irqsave(&speakup_info.spinlock, flags);
72 	jiffy_delta_val = jiffy_delta->u.n.value;
73 	spin_unlock_irqrestore(&speakup_info.spinlock, flags);
74 
75 	jiff_max = jiffies + jiffy_delta_val;
76 	while (!kthread_should_stop()) {
77 		spin_lock_irqsave(&speakup_info.spinlock, flags);
78 		if (speakup_info.flushing) {
79 			speakup_info.flushing = 0;
80 			spin_unlock_irqrestore(&speakup_info.spinlock, flags);
81 			synth->flush(synth);
82 			continue;
83 		}
84 		if (!unicode)
85 			synth_buffer_skip_nonlatin1();
86 		if (synth_buffer_empty()) {
87 			spin_unlock_irqrestore(&speakup_info.spinlock, flags);
88 			break;
89 		}
90 		ch = synth_buffer_peek();
91 		set_current_state(TASK_INTERRUPTIBLE);
92 		full_time_val = full_time->u.n.value;
93 		spin_unlock_irqrestore(&speakup_info.spinlock, flags);
94 		if (ch == '\n')
95 			ch = synth->procspeech;
96 		if (unicode)
97 			ret = synth->io_ops->synth_out_unicode(synth, ch);
98 		else
99 			ret = synth->io_ops->synth_out(synth, ch);
100 		if (!ret) {
101 			schedule_timeout(msecs_to_jiffies(full_time_val));
102 			continue;
103 		}
104 		if (time_after_eq(jiffies, jiff_max) && (ch == SPACE)) {
105 			spin_lock_irqsave(&speakup_info.spinlock, flags);
106 			jiffy_delta_val = jiffy_delta->u.n.value;
107 			delay_time_val = delay_time->u.n.value;
108 			full_time_val = full_time->u.n.value;
109 			spin_unlock_irqrestore(&speakup_info.spinlock, flags);
110 			if (synth->io_ops->synth_out(synth, synth->procspeech))
111 				schedule_timeout(
112 					msecs_to_jiffies(delay_time_val));
113 			else
114 				schedule_timeout(
115 					msecs_to_jiffies(full_time_val));
116 			jiff_max = jiffies + jiffy_delta_val;
117 		}
118 		set_current_state(TASK_RUNNING);
119 		spin_lock_irqsave(&speakup_info.spinlock, flags);
120 		synth_buffer_getc();
121 		spin_unlock_irqrestore(&speakup_info.spinlock, flags);
122 	}
123 	synth->io_ops->synth_out(synth, synth->procspeech);
124 }
125 
126 void spk_do_catch_up(struct spk_synth *synth)
127 {
128 	_spk_do_catch_up(synth, 0);
129 }
130 EXPORT_SYMBOL_GPL(spk_do_catch_up);
131 
132 void spk_do_catch_up_unicode(struct spk_synth *synth)
133 {
134 	_spk_do_catch_up(synth, 1);
135 }
136 EXPORT_SYMBOL_GPL(spk_do_catch_up_unicode);
137 
138 void spk_synth_flush(struct spk_synth *synth)
139 {
140 	synth->io_ops->flush_buffer(synth);
141 	synth->io_ops->synth_out(synth, synth->clear);
142 }
143 EXPORT_SYMBOL_GPL(spk_synth_flush);
144 
145 unsigned char spk_synth_get_index(struct spk_synth *synth)
146 {
147 	return synth->io_ops->synth_in_nowait(synth);
148 }
149 EXPORT_SYMBOL_GPL(spk_synth_get_index);
150 
151 int spk_synth_is_alive_nop(struct spk_synth *synth)
152 {
153 	synth->alive = 1;
154 	return 1;
155 }
156 EXPORT_SYMBOL_GPL(spk_synth_is_alive_nop);
157 
158 int spk_synth_is_alive_restart(struct spk_synth *synth)
159 {
160 	if (synth->alive)
161 		return 1;
162 	if (synth->io_ops->wait_for_xmitr(synth) > 0) {
163 		/* restart */
164 		synth->alive = 1;
165 		synth_printf("%s", synth->init);
166 		return 2; /* reenabled */
167 	}
168 	pr_warn("%s: can't restart synth\n", synth->long_name);
169 	return 0;
170 }
171 EXPORT_SYMBOL_GPL(spk_synth_is_alive_restart);
172 
173 static void thread_wake_up(struct timer_list *unused)
174 {
175 	wake_up_interruptible_all(&speakup_event);
176 }
177 
178 static DEFINE_TIMER(thread_timer, thread_wake_up);
179 
180 void synth_start(void)
181 {
182 	struct var_t *trigger_time;
183 
184 	if (!synth->alive) {
185 		synth_buffer_clear();
186 		return;
187 	}
188 	trigger_time = spk_get_var(TRIGGER);
189 	if (!timer_pending(&thread_timer))
190 		mod_timer(&thread_timer, jiffies +
191 			msecs_to_jiffies(trigger_time->u.n.value));
192 }
193 
194 void spk_do_flush(void)
195 {
196 	if (!synth)
197 		return;
198 
199 	speakup_info.flushing = 1;
200 	synth_buffer_clear();
201 	if (synth->alive) {
202 		if (spk_pitch_shift) {
203 			synth_printf("%s", spk_pitch_buff);
204 			spk_pitch_shift = 0;
205 		}
206 	}
207 	wake_up_interruptible_all(&speakup_event);
208 	wake_up_process(speakup_task);
209 }
210 
211 void synth_write(const char *_buf, size_t count)
212 {
213 	const unsigned char *buf = (const unsigned char *) _buf;
214 
215 	while (count--)
216 		synth_buffer_add(*buf++);
217 	synth_start();
218 }
219 
220 /* Consume one utf-8 character from buf (that contains up to count bytes),
221  * returns the unicode codepoint if valid, -1 otherwise.
222  * In all cases, returns the number of consumed bytes in *consumed,
223  * and the minimum number of bytes that would be needed for the next character
224  * in *want.
225  */
226 s32 synth_utf8_get(const char *buf, size_t count, size_t *consumed, size_t *want)
227 {
228 	unsigned char c = buf[0];
229 	int nbytes = 8 - fls(c ^ 0xff);
230 	u32 value;
231 	size_t i;
232 
233 	switch (nbytes) {
234 	case 8: /* 0xff */
235 	case 7: /* 0xfe */
236 	case 1: /* 0x80 */
237 		/* Invalid, drop */
238 		*consumed = 1;
239 		*want = 1;
240 		return -1;
241 
242 	case 0:
243 		/* ASCII, take as such */
244 		*consumed = 1;
245 		*want = 1;
246 		return c;
247 
248 	default:
249 		/* 2..6-byte UTF-8 */
250 
251 		if (count < nbytes) {
252 			/* We don't have it all */
253 			*consumed = 0;
254 			*want = nbytes;
255 			return -1;
256 		}
257 
258 		/* First byte */
259 		value = c & ((1u << (7 - nbytes)) - 1);
260 
261 		/* Other bytes */
262 		for (i = 1; i < nbytes; i++) {
263 			c = buf[i];
264 			if ((c & 0xc0) != 0x80)	{
265 				/* Invalid, drop the head */
266 				*consumed = i;
267 				*want = 1;
268 				return -1;
269 			}
270 			value = (value << 6) | (c & 0x3f);
271 		}
272 
273 		*consumed = nbytes;
274 		*want = 1;
275 		return value;
276 	}
277 }
278 
279 void synth_writeu(const char *buf, size_t count)
280 {
281 	size_t i, consumed, want;
282 
283 	/* Convert to u16 */
284 	for (i = 0; i < count; i++) {
285 		s32 value;
286 
287 		value = synth_utf8_get(buf + i, count - i, &consumed, &want);
288 		if (value == -1) {
289 			/* Invalid or incomplete */
290 
291 			if (want > count - i)
292 				/* We don't have it all, stop */
293 				count = i;
294 
295 			continue;
296 		}
297 
298 		if (value < 0x10000)
299 			synth_buffer_add(value);
300 	}
301 
302 	synth_start();
303 }
304 
305 void synth_printf(const char *fmt, ...)
306 {
307 	va_list args;
308 	unsigned char buf[160];
309 	int r;
310 
311 	va_start(args, fmt);
312 	r = vsnprintf(buf, sizeof(buf), fmt, args);
313 	va_end(args);
314 	if (r > sizeof(buf) - 1)
315 		r = sizeof(buf) - 1;
316 
317 	synth_writeu(buf, r);
318 }
319 EXPORT_SYMBOL_GPL(synth_printf);
320 
321 void synth_putwc(u16 wc)
322 {
323 	synth_buffer_add(wc);
324 }
325 EXPORT_SYMBOL_GPL(synth_putwc);
326 
327 void synth_putwc_s(u16 wc)
328 {
329 	synth_buffer_add(wc);
330 	synth_start();
331 }
332 EXPORT_SYMBOL_GPL(synth_putwc_s);
333 
334 void synth_putws(const u16 *buf)
335 {
336 	const u16 *p;
337 
338 	for (p = buf; *p; p++)
339 		synth_buffer_add(*p);
340 }
341 EXPORT_SYMBOL_GPL(synth_putws);
342 
343 void synth_putws_s(const u16 *buf)
344 {
345 	synth_putws(buf);
346 	synth_start();
347 }
348 EXPORT_SYMBOL_GPL(synth_putws_s);
349 
350 static int index_count;
351 static int sentence_count;
352 
353 void spk_reset_index_count(int sc)
354 {
355 	static int first = 1;
356 
357 	if (first)
358 		first = 0;
359 	else
360 		synth->get_index(synth);
361 	index_count = 0;
362 	sentence_count = sc;
363 }
364 
365 int synth_supports_indexing(void)
366 {
367 	if (synth->get_index)
368 		return 1;
369 	return 0;
370 }
371 
372 void synth_insert_next_index(int sent_num)
373 {
374 	int out;
375 
376 	if (synth->alive) {
377 		if (sent_num == 0) {
378 			synth->indexing.currindex++;
379 			index_count++;
380 			if (synth->indexing.currindex >
381 					synth->indexing.highindex)
382 				synth->indexing.currindex =
383 					synth->indexing.lowindex;
384 		}
385 
386 		out = synth->indexing.currindex * 10 + sent_num;
387 		synth_printf(synth->indexing.command, out, out);
388 	}
389 }
390 
391 void spk_get_index_count(int *linecount, int *sentcount)
392 {
393 	int ind = synth->get_index(synth);
394 
395 	if (ind) {
396 		sentence_count = ind % 10;
397 
398 		if ((ind / 10) <= synth->indexing.currindex)
399 			index_count = synth->indexing.currindex - (ind / 10);
400 		else
401 			index_count = synth->indexing.currindex
402 				- synth->indexing.lowindex
403 				+ synth->indexing.highindex - (ind / 10) + 1;
404 	}
405 	*sentcount = sentence_count;
406 	*linecount = index_count;
407 }
408 
409 static struct resource synth_res;
410 
411 int synth_request_region(unsigned long start, unsigned long n)
412 {
413 	struct resource *parent = &ioport_resource;
414 
415 	memset(&synth_res, 0, sizeof(synth_res));
416 	synth_res.name = synth->name;
417 	synth_res.start = start;
418 	synth_res.end = start + n - 1;
419 	synth_res.flags = IORESOURCE_BUSY;
420 	return request_resource(parent, &synth_res);
421 }
422 EXPORT_SYMBOL_GPL(synth_request_region);
423 
424 int synth_release_region(unsigned long start, unsigned long n)
425 {
426 	return release_resource(&synth_res);
427 }
428 EXPORT_SYMBOL_GPL(synth_release_region);
429 
430 struct var_t synth_time_vars[] = {
431 	{ DELAY, .u.n = {NULL, 100, 100, 2000, 0, 0, NULL } },
432 	{ TRIGGER, .u.n = {NULL, 20, 10, 2000, 0, 0, NULL } },
433 	{ JIFFY, .u.n = {NULL, 50, 20, 200, 0, 0, NULL } },
434 	{ FULL, .u.n = {NULL, 400, 200, 60000, 0, 0, NULL } },
435 	{ FLUSH, .u.n = {NULL, 4000, 10, 4000, 0, 0, NULL } },
436 	V_LAST_VAR
437 };
438 
439 /* called by: speakup_init() */
440 int synth_init(char *synth_name)
441 {
442 	int ret = 0;
443 	struct spk_synth *tmp, *synth = NULL;
444 
445 	if (!synth_name)
446 		return 0;
447 
448 	if (strcmp(synth_name, "none") == 0) {
449 		mutex_lock(&spk_mutex);
450 		synth_release();
451 		mutex_unlock(&spk_mutex);
452 		return 0;
453 	}
454 
455 	mutex_lock(&spk_mutex);
456 	/* First, check if we already have it loaded. */
457 	list_for_each_entry(tmp, &synths, node) {
458 		if (strcmp(tmp->name, synth_name) == 0)
459 			synth = tmp;
460 	}
461 
462 	/* If we got one, initialize it now. */
463 	if (synth)
464 		ret = do_synth_init(synth);
465 	else
466 		ret = -ENODEV;
467 	mutex_unlock(&spk_mutex);
468 
469 	return ret;
470 }
471 
472 /* called by: synth_add() */
473 static int do_synth_init(struct spk_synth *in_synth)
474 {
475 	struct var_t *var;
476 
477 	synth_release();
478 	if (in_synth->checkval != SYNTH_CHECK)
479 		return -EINVAL;
480 	synth = in_synth;
481 	synth->alive = 0;
482 	pr_warn("synth probe\n");
483 	if (synth->probe(synth) < 0) {
484 		pr_warn("%s: device probe failed\n", in_synth->name);
485 		synth = NULL;
486 		return -ENODEV;
487 	}
488 	synth_time_vars[0].u.n.value =
489 		synth_time_vars[0].u.n.default_val = synth->delay;
490 	synth_time_vars[1].u.n.value =
491 		synth_time_vars[1].u.n.default_val = synth->trigger;
492 	synth_time_vars[2].u.n.value =
493 		synth_time_vars[2].u.n.default_val = synth->jiffies;
494 	synth_time_vars[3].u.n.value =
495 		synth_time_vars[3].u.n.default_val = synth->full;
496 	synth_time_vars[4].u.n.value =
497 		synth_time_vars[4].u.n.default_val = synth->flush_time;
498 	synth_printf("%s", synth->init);
499 	for (var = synth->vars;
500 		(var->var_id >= 0) && (var->var_id < MAXVARS); var++)
501 		speakup_register_var(var);
502 	if (!spk_quiet_boot)
503 		synth_printf("%s found\n", synth->long_name);
504 	if (synth->attributes.name &&
505 	    sysfs_create_group(speakup_kobj, &synth->attributes) < 0)
506 		return -ENOMEM;
507 	synth_flags = synth->flags;
508 	wake_up_interruptible_all(&speakup_event);
509 	if (speakup_task)
510 		wake_up_process(speakup_task);
511 	return 0;
512 }
513 
514 void synth_release(void)
515 {
516 	struct var_t *var;
517 	unsigned long flags;
518 
519 	if (!synth)
520 		return;
521 	spin_lock_irqsave(&speakup_info.spinlock, flags);
522 	pr_info("releasing synth %s\n", synth->name);
523 	synth->alive = 0;
524 	del_timer(&thread_timer);
525 	spin_unlock_irqrestore(&speakup_info.spinlock, flags);
526 	if (synth->attributes.name)
527 		sysfs_remove_group(speakup_kobj, &synth->attributes);
528 	for (var = synth->vars; var->var_id != MAXVARS; var++)
529 		speakup_unregister_var(var->var_id);
530 	synth->release(synth);
531 	synth = NULL;
532 }
533 
534 /* called by: all_driver_init() */
535 int synth_add(struct spk_synth *in_synth)
536 {
537 	int status = 0;
538 	struct spk_synth *tmp;
539 
540 	mutex_lock(&spk_mutex);
541 
542 	list_for_each_entry(tmp, &synths, node) {
543 		if (tmp == in_synth) {
544 			mutex_unlock(&spk_mutex);
545 			return 0;
546 		}
547 	}
548 
549 	if (in_synth->startup)
550 		status = do_synth_init(in_synth);
551 
552 	if (!status)
553 		list_add_tail(&in_synth->node, &synths);
554 
555 	mutex_unlock(&spk_mutex);
556 	return status;
557 }
558 EXPORT_SYMBOL_GPL(synth_add);
559 
560 void synth_remove(struct spk_synth *in_synth)
561 {
562 	mutex_lock(&spk_mutex);
563 	if (synth == in_synth)
564 		synth_release();
565 	list_del(&in_synth->node);
566 	module_status = 0;
567 	mutex_unlock(&spk_mutex);
568 }
569 EXPORT_SYMBOL_GPL(synth_remove);
570 
571 struct spk_synth *synth_current(void)
572 {
573 	return synth;
574 }
575 EXPORT_SYMBOL_GPL(synth_current);
576 
577 short spk_punc_masks[] = { 0, SOME, MOST, PUNC, PUNC | B_SYM };
578