1 // SPDX-License-Identifier: GPL-2.0+
2 /* speakup_soft.c - speakup driver to register and make available
3  * a user space device for software synthesizers.  written by: Kirk
4  * Reiser <kirk@braille.uwo.ca>
5  *
6  * Copyright (C) 2003  Kirk Reiser.
7  *
8  * this code is specificly written as a driver for the speakup screenreview
9  * package and is not a general device driver.
10  */
11 
12 #include <linux/unistd.h>
13 #include <linux/miscdevice.h>	/* for misc_register, and MISC_DYNAMIC_MINOR */
14 #include <linux/poll.h>		/* for poll_wait() */
15 
16 /* schedule(), signal_pending(), TASK_INTERRUPTIBLE */
17 #include <linux/sched/signal.h>
18 
19 #include "spk_priv.h"
20 #include "speakup.h"
21 
22 #define DRV_VERSION "2.6"
23 #define PROCSPEECH 0x0d
24 #define CLEAR_SYNTH 0x18
25 
26 static int softsynth_probe(struct spk_synth *synth);
27 static void softsynth_release(struct spk_synth *synth);
28 static int softsynth_is_alive(struct spk_synth *synth);
29 static unsigned char get_index(struct spk_synth *synth);
30 
31 static struct miscdevice synth_device, synthu_device;
32 static int init_pos;
33 static int misc_registered;
34 
35 static struct var_t vars[] = {
36 	{ CAPS_START, .u.s = {"\x01+3p" } },
37 	{ CAPS_STOP, .u.s = {"\x01-3p" } },
38 	{ PAUSE, .u.n = {"\x01P" } },
39 	{ RATE, .u.n = {"\x01%ds", 2, 0, 9, 0, 0, NULL } },
40 	{ PITCH, .u.n = {"\x01%dp", 5, 0, 9, 0, 0, NULL } },
41 	{ INFLECTION, .u.n = {"\x01%dr", 5, 0, 9, 0, 0, NULL } },
42 	{ VOL, .u.n = {"\x01%dv", 5, 0, 9, 0, 0, NULL } },
43 	{ TONE, .u.n = {"\x01%dx", 1, 0, 2, 0, 0, NULL } },
44 	{ PUNCT, .u.n = {"\x01%db", 0, 0, 2, 0, 0, NULL } },
45 	{ VOICE, .u.n = {"\x01%do", 0, 0, 7, 0, 0, NULL } },
46 	{ FREQUENCY, .u.n = {"\x01%df", 5, 0, 9, 0, 0, NULL } },
47 	{ DIRECT, .u.n = {NULL, 0, 0, 1, 0, 0, NULL } },
48 	V_LAST_VAR
49 };
50 
51 /* These attributes will appear in /sys/accessibility/speakup/soft. */
52 
53 static struct kobj_attribute caps_start_attribute =
54 	__ATTR(caps_start, 0644, spk_var_show, spk_var_store);
55 static struct kobj_attribute caps_stop_attribute =
56 	__ATTR(caps_stop, 0644, spk_var_show, spk_var_store);
57 static struct kobj_attribute freq_attribute =
58 	__ATTR(freq, 0644, spk_var_show, spk_var_store);
59 static struct kobj_attribute pitch_attribute =
60 	__ATTR(pitch, 0644, spk_var_show, spk_var_store);
61 static struct kobj_attribute inflection_attribute =
62 	__ATTR(inflection, 0644, spk_var_show, spk_var_store);
63 static struct kobj_attribute punct_attribute =
64 	__ATTR(punct, 0644, spk_var_show, spk_var_store);
65 static struct kobj_attribute rate_attribute =
66 	__ATTR(rate, 0644, spk_var_show, spk_var_store);
67 static struct kobj_attribute tone_attribute =
68 	__ATTR(tone, 0644, spk_var_show, spk_var_store);
69 static struct kobj_attribute voice_attribute =
70 	__ATTR(voice, 0644, spk_var_show, spk_var_store);
71 static struct kobj_attribute vol_attribute =
72 	__ATTR(vol, 0644, spk_var_show, spk_var_store);
73 
74 /*
75  * We should uncomment the following definition, when we agree on a
76  * method of passing a language designation to the software synthesizer.
77  * static struct kobj_attribute lang_attribute =
78  *	__ATTR(lang, 0644, spk_var_show, spk_var_store);
79  */
80 
81 static struct kobj_attribute delay_time_attribute =
82 	__ATTR(delay_time, 0644, spk_var_show, spk_var_store);
83 static struct kobj_attribute direct_attribute =
84 	__ATTR(direct, 0644, spk_var_show, spk_var_store);
85 static struct kobj_attribute full_time_attribute =
86 	__ATTR(full_time, 0644, spk_var_show, spk_var_store);
87 static struct kobj_attribute jiffy_delta_attribute =
88 	__ATTR(jiffy_delta, 0644, spk_var_show, spk_var_store);
89 static struct kobj_attribute trigger_time_attribute =
90 	__ATTR(trigger_time, 0644, spk_var_show, spk_var_store);
91 
92 /*
93  * Create a group of attributes so that we can create and destroy them all
94  * at once.
95  */
96 static struct attribute *synth_attrs[] = {
97 	&caps_start_attribute.attr,
98 	&caps_stop_attribute.attr,
99 	&freq_attribute.attr,
100 /*	&lang_attribute.attr, */
101 	&pitch_attribute.attr,
102 	&inflection_attribute.attr,
103 	&punct_attribute.attr,
104 	&rate_attribute.attr,
105 	&tone_attribute.attr,
106 	&voice_attribute.attr,
107 	&vol_attribute.attr,
108 	&delay_time_attribute.attr,
109 	&direct_attribute.attr,
110 	&full_time_attribute.attr,
111 	&jiffy_delta_attribute.attr,
112 	&trigger_time_attribute.attr,
113 	NULL,	/* need to NULL terminate the list of attributes */
114 };
115 
116 static struct spk_synth synth_soft = {
117 	.name = "soft",
118 	.version = DRV_VERSION,
119 	.long_name = "software synth",
120 	.init = "\01@\x01\x31y\n",
121 	.procspeech = PROCSPEECH,
122 	.delay = 0,
123 	.trigger = 0,
124 	.jiffies = 0,
125 	.full = 0,
126 	.startup = SYNTH_START,
127 	.checkval = SYNTH_CHECK,
128 	.vars = vars,
129 	.io_ops = NULL,
130 	.probe = softsynth_probe,
131 	.release = softsynth_release,
132 	.synth_immediate = NULL,
133 	.catch_up = NULL,
134 	.flush = NULL,
135 	.is_alive = softsynth_is_alive,
136 	.synth_adjust = NULL,
137 	.read_buff_add = NULL,
138 	.get_index = get_index,
139 	.indexing = {
140 		.command = "\x01%di",
141 		.lowindex = 1,
142 		.highindex = 5,
143 		.currindex = 1,
144 	},
145 	.attributes = {
146 		.attrs = synth_attrs,
147 		.name = "soft",
148 	},
149 };
150 
151 static char *get_initstring(void)
152 {
153 	static char buf[40];
154 	char *cp;
155 	struct var_t *var;
156 
157 	memset(buf, 0, sizeof(buf));
158 	cp = buf;
159 	var = synth_soft.vars;
160 	while (var->var_id != MAXVARS) {
161 		if (var->var_id != CAPS_START && var->var_id != CAPS_STOP &&
162 		    var->var_id != PAUSE && var->var_id != DIRECT)
163 			cp = cp + sprintf(cp, var->u.n.synth_fmt,
164 					  var->u.n.value);
165 		var++;
166 	}
167 	cp = cp + sprintf(cp, "\n");
168 	return buf;
169 }
170 
171 static int softsynth_open(struct inode *inode, struct file *fp)
172 {
173 	unsigned long flags;
174 	/*if ((fp->f_flags & O_ACCMODE) != O_RDONLY) */
175 	/*	return -EPERM; */
176 	spin_lock_irqsave(&speakup_info.spinlock, flags);
177 	if (synth_soft.alive) {
178 		spin_unlock_irqrestore(&speakup_info.spinlock, flags);
179 		return -EBUSY;
180 	}
181 	synth_soft.alive = 1;
182 	spin_unlock_irqrestore(&speakup_info.spinlock, flags);
183 	return 0;
184 }
185 
186 static int softsynth_close(struct inode *inode, struct file *fp)
187 {
188 	unsigned long flags;
189 
190 	spin_lock_irqsave(&speakup_info.spinlock, flags);
191 	synth_soft.alive = 0;
192 	init_pos = 0;
193 	spin_unlock_irqrestore(&speakup_info.spinlock, flags);
194 	/* Make sure we let applications go before leaving */
195 	speakup_start_ttys();
196 	return 0;
197 }
198 
199 static ssize_t softsynthx_read(struct file *fp, char __user *buf, size_t count,
200 			       loff_t *pos, int unicode)
201 {
202 	int chars_sent = 0;
203 	char __user *cp;
204 	char *init;
205 	size_t bytes_per_ch = unicode ? 3 : 1;
206 	u16 ch;
207 	int empty;
208 	unsigned long flags;
209 	DEFINE_WAIT(wait);
210 
211 	if (count < bytes_per_ch)
212 		return -EINVAL;
213 
214 	spin_lock_irqsave(&speakup_info.spinlock, flags);
215 	synth_soft.alive = 1;
216 	while (1) {
217 		prepare_to_wait(&speakup_event, &wait, TASK_INTERRUPTIBLE);
218 		if (synth_current() == &synth_soft) {
219 			if (!unicode)
220 				synth_buffer_skip_nonlatin1();
221 			if (!synth_buffer_empty() || speakup_info.flushing)
222 				break;
223 		}
224 		spin_unlock_irqrestore(&speakup_info.spinlock, flags);
225 		if (fp->f_flags & O_NONBLOCK) {
226 			finish_wait(&speakup_event, &wait);
227 			return -EAGAIN;
228 		}
229 		if (signal_pending(current)) {
230 			finish_wait(&speakup_event, &wait);
231 			return -ERESTARTSYS;
232 		}
233 		schedule();
234 		spin_lock_irqsave(&speakup_info.spinlock, flags);
235 	}
236 	finish_wait(&speakup_event, &wait);
237 
238 	cp = buf;
239 	init = get_initstring();
240 
241 	/* Keep 3 bytes available for a 16bit UTF-8-encoded character */
242 	while (chars_sent <= count - bytes_per_ch) {
243 		if (synth_current() != &synth_soft)
244 			break;
245 		if (speakup_info.flushing) {
246 			speakup_info.flushing = 0;
247 			ch = '\x18';
248 		} else if (init[init_pos]) {
249 			ch = init[init_pos++];
250 		} else {
251 			if (!unicode)
252 				synth_buffer_skip_nonlatin1();
253 			if (synth_buffer_empty())
254 				break;
255 			ch = synth_buffer_getc();
256 		}
257 		spin_unlock_irqrestore(&speakup_info.spinlock, flags);
258 
259 		if ((!unicode && ch < 0x100) || (unicode && ch < 0x80)) {
260 			u_char c = ch;
261 
262 			if (copy_to_user(cp, &c, 1))
263 				return -EFAULT;
264 
265 			chars_sent++;
266 			cp++;
267 		} else if (unicode && ch < 0x800) {
268 			u_char s[2] = {
269 				0xc0 | (ch >> 6),
270 				0x80 | (ch & 0x3f)
271 			};
272 
273 			if (copy_to_user(cp, s, sizeof(s)))
274 				return -EFAULT;
275 
276 			chars_sent += sizeof(s);
277 			cp += sizeof(s);
278 		} else if (unicode) {
279 			u_char s[3] = {
280 				0xe0 | (ch >> 12),
281 				0x80 | ((ch >> 6) & 0x3f),
282 				0x80 | (ch & 0x3f)
283 			};
284 
285 			if (copy_to_user(cp, s, sizeof(s)))
286 				return -EFAULT;
287 
288 			chars_sent += sizeof(s);
289 			cp += sizeof(s);
290 		}
291 
292 		spin_lock_irqsave(&speakup_info.spinlock, flags);
293 	}
294 	*pos += chars_sent;
295 	empty = synth_buffer_empty();
296 	spin_unlock_irqrestore(&speakup_info.spinlock, flags);
297 	if (empty) {
298 		speakup_start_ttys();
299 		*pos = 0;
300 	}
301 	return chars_sent;
302 }
303 
304 static ssize_t softsynth_read(struct file *fp, char __user *buf, size_t count,
305 			      loff_t *pos)
306 {
307 	return softsynthx_read(fp, buf, count, pos, 0);
308 }
309 
310 static ssize_t softsynthu_read(struct file *fp, char __user *buf, size_t count,
311 			       loff_t *pos)
312 {
313 	return softsynthx_read(fp, buf, count, pos, 1);
314 }
315 
316 static int last_index;
317 
318 static ssize_t softsynth_write(struct file *fp, const char __user *buf,
319 			       size_t count, loff_t *pos)
320 {
321 	unsigned long supplied_index = 0;
322 	int converted;
323 
324 	converted = kstrtoul_from_user(buf, count, 0, &supplied_index);
325 
326 	if (converted < 0)
327 		return converted;
328 
329 	last_index = supplied_index;
330 	return count;
331 }
332 
333 static __poll_t softsynth_poll(struct file *fp, struct poll_table_struct *wait)
334 {
335 	unsigned long flags;
336 	__poll_t ret = 0;
337 
338 	poll_wait(fp, &speakup_event, wait);
339 
340 	spin_lock_irqsave(&speakup_info.spinlock, flags);
341 	if (synth_current() == &synth_soft &&
342 	    (!synth_buffer_empty() || speakup_info.flushing))
343 		ret = EPOLLIN | EPOLLRDNORM;
344 	spin_unlock_irqrestore(&speakup_info.spinlock, flags);
345 	return ret;
346 }
347 
348 static unsigned char get_index(struct spk_synth *synth)
349 {
350 	int rv;
351 
352 	rv = last_index;
353 	last_index = 0;
354 	return rv;
355 }
356 
357 static const struct file_operations softsynth_fops = {
358 	.owner = THIS_MODULE,
359 	.poll = softsynth_poll,
360 	.read = softsynth_read,
361 	.write = softsynth_write,
362 	.open = softsynth_open,
363 	.release = softsynth_close,
364 };
365 
366 static const struct file_operations softsynthu_fops = {
367 	.owner = THIS_MODULE,
368 	.poll = softsynth_poll,
369 	.read = softsynthu_read,
370 	.write = softsynth_write,
371 	.open = softsynth_open,
372 	.release = softsynth_close,
373 };
374 
375 static int softsynth_probe(struct spk_synth *synth)
376 {
377 	if (misc_registered != 0)
378 		return 0;
379 	memset(&synth_device, 0, sizeof(synth_device));
380 	synth_device.minor = MISC_DYNAMIC_MINOR;
381 	synth_device.name = "softsynth";
382 	synth_device.fops = &softsynth_fops;
383 	if (misc_register(&synth_device)) {
384 		pr_warn("Couldn't initialize miscdevice /dev/softsynth.\n");
385 		return -ENODEV;
386 	}
387 
388 	memset(&synthu_device, 0, sizeof(synthu_device));
389 	synthu_device.minor = MISC_DYNAMIC_MINOR;
390 	synthu_device.name = "softsynthu";
391 	synthu_device.fops = &softsynthu_fops;
392 	if (misc_register(&synthu_device)) {
393 		pr_warn("Couldn't initialize miscdevice /dev/softsynthu.\n");
394 		return -ENODEV;
395 	}
396 
397 	misc_registered = 1;
398 	pr_info("initialized device: /dev/softsynth, node (MAJOR 10, MINOR %d)\n",
399 		synth_device.minor);
400 	pr_info("initialized device: /dev/softsynthu, node (MAJOR 10, MINOR %d)\n",
401 		synthu_device.minor);
402 	return 0;
403 }
404 
405 static void softsynth_release(struct spk_synth *synth)
406 {
407 	misc_deregister(&synth_device);
408 	misc_deregister(&synthu_device);
409 	misc_registered = 0;
410 	pr_info("unregistered /dev/softsynth\n");
411 	pr_info("unregistered /dev/softsynthu\n");
412 }
413 
414 static int softsynth_is_alive(struct spk_synth *synth)
415 {
416 	if (synth_soft.alive)
417 		return 1;
418 	return 0;
419 }
420 
421 module_param_named(start, synth_soft.startup, short, 0444);
422 
423 MODULE_PARM_DESC(start, "Start the synthesizer once it is loaded.");
424 
425 module_spk_synth(synth_soft);
426 
427 MODULE_AUTHOR("Kirk Reiser <kirk@braille.uwo.ca>");
428 MODULE_DESCRIPTION("Speakup userspace software synthesizer support");
429 MODULE_LICENSE("GPL");
430 MODULE_VERSION(DRV_VERSION);
431