text: // SPDX-License-Identifier: GPL-2.0
  #include <linux/types.h>
  #include <linux/ctype.h>	/* for isdigit() and friends */
  #include <linux/fs.h>
  #include <linux/mm.h>		/* for verify_area */
  #include <linux/errno.h>	/* for -EBUSY */
  #include <linux/ioport.h>	/* for check_region, request_region */
  #include <linux/interrupt.h>
  #include <linux/delay.h>	/* for loops_per_sec */
  #include <linux/kmod.h>
  #include <linux/jiffies.h>
  #include <linux/uaccess.h>	/* for copy_from_user */
  #include <linux/sched.h>
  #include <linux/timer.h>
  #include <linux/kthread.h>
  
  #include "spk_priv.h"
  #include "speakup.h"
  #include "serialio.h"
  
  static LIST_HEAD(synths);
  struct spk_synth *synth;
  char spk_pitch_buff[32] = "";
  static int module_status;
  bool spk_quiet_boot;
  
  struct speakup_info_t speakup_info = {
  	/*
  	 * This spinlock is used to protect the entire speakup machinery, and
  	 * must be taken at each kernel->speakup transition and released at
  	 * each corresponding speakup->kernel transition.
  	 *
  	 * The progression thread only interferes with the speakup machinery
  	 * through the synth buffer, so only needs to take the lock
  	 * while tinkering with the buffer.
  	 *
  	 * We use spin_lock/trylock_irqsave and spin_unlock_irqrestore with this
  	 * spinlock because speakup needs to disable the keyboard IRQ.
  	 */
  	.spinlock = __SPIN_LOCK_UNLOCKED(speakup_info.spinlock),
  	.flushing = 0,
  };
  EXPORT_SYMBOL_GPL(speakup_info);
  
  static int do_synth_init(struct spk_synth *in_synth);
  
  /*
   * Main loop of the progression thread: keep eating from the buffer
   * and push to the serial port, waiting as needed
   *
   * For devices that have a "full" notification mechanism, the driver can
   * adapt the loop the way they prefer.
   */
  static void _spk_do_catch_up(struct spk_synth *synth, int unicode)
  {
  	u16 ch;
  	unsigned long flags;
  	unsigned long jiff_max;
  	struct var_t *delay_time;
  	struct var_t *full_time;
  	struct var_t *jiffy_delta;
  	int jiffy_delta_val;
  	int delay_time_val;
  	int full_time_val;
  	int ret;
  
  	jiffy_delta = spk_get_var(JIFFY);
  	full_time = spk_get_var(FULL);
  	delay_time = spk_get_var(DELAY);
  
  	spin_lock_irqsave(&speakup_info.spinlock, flags);
  	jiffy_delta_val = jiffy_delta->u.n.value;
  	spin_unlock_irqrestore(&speakup_info.spinlock, flags);
  
  	jiff_max = jiffies + jiffy_delta_val;
  	while (!kthread_should_stop()) {
  		spin_lock_irqsave(&speakup_info.spinlock, flags);
  		if (speakup_info.flushing) {
  			speakup_info.flushing = 0;
  			spin_unlock_irqrestore(&speakup_info.spinlock, flags);
  			synth->flush(synth);
  			continue;
  		}
  		if (!unicode)
  			synth_buffer_skip_nonlatin1();
  		if (synth_buffer_empty()) {
  			spin_unlock_irqrestore(&speakup_info.spinlock, flags);
  			break;
  		}
  		ch = synth_buffer_peek();
  		set_current_state(TASK_INTERRUPTIBLE);
  		full_time_val = full_time->u.n.value;
  		spin_unlock_irqrestore(&speakup_info.spinlock, flags);
  		if (ch == '\n')
  			ch = synth->procspeech;
  		if (unicode)
  			ret = synth->io_ops->synth_out_unicode(synth, ch);
  		else
  			ret = synth->io_ops->synth_out(synth, ch);
  		if (!ret) {
  			schedule_timeout(msecs_to_jiffies(full_time_val));
  			continue;
  		}
  		if (time_after_eq(jiffies, jiff_max) && (ch == SPACE)) {
  			spin_lock_irqsave(&speakup_info.spinlock, flags);
  			jiffy_delta_val = jiffy_delta->u.n.value;
  			delay_time_val = delay_time->u.n.value;
  			full_time_val = full_time->u.n.value;
  			spin_unlock_irqrestore(&speakup_info.spinlock, flags);
  			if (synth->io_ops->synth_out(synth, synth->procspeech))
  				schedule_timeout(
  					msecs_to_jiffies(delay_time_val));
  			else
  				schedule_timeout(
  					msecs_to_jiffies(full_time_val));
  			jiff_max = jiffies + jiffy_delta_val;
  		}
  		set_current_state(TASK_RUNNING);
  		spin_lock_irqsave(&speakup_info.spinlock, flags);
  		synth_buffer_getc();
  		spin_unlock_irqrestore(&speakup_info.spinlock, flags);
  	}
  	synth->io_ops->synth_out(synth, synth->procspeech);
  }
  
  void spk_do_catch_up(struct spk_synth *synth)
  {
  	_spk_do_catch_up(synth, 0);
  }
  EXPORT_SYMBOL_GPL(spk_do_catch_up);
  
  void spk_do_catch_up_unicode(struct spk_synth *synth)
  {
  	_spk_do_catch_up(synth, 1);
  }
  EXPORT_SYMBOL_GPL(spk_do_catch_up_unicode);
  
  void spk_synth_flush(struct spk_synth *synth)
  {
  	synth->io_ops->flush_buffer();
  	synth->io_ops->synth_out(synth, synth->clear);
  }
  EXPORT_SYMBOL_GPL(spk_synth_flush);
  
  unsigned char spk_synth_get_index(struct spk_synth *synth)
  {
  	return synth->io_ops->synth_in_nowait();
  }
  EXPORT_SYMBOL_GPL(spk_synth_get_index);
  
  int spk_synth_is_alive_nop(struct spk_synth *synth)
  {
  	synth->alive = 1;
  	return 1;
  }
  EXPORT_SYMBOL_GPL(spk_synth_is_alive_nop);
  
  int spk_synth_is_alive_restart(struct spk_synth *synth)
  {
  	if (synth->alive)
  		return 1;
  	if (spk_wait_for_xmitr(synth) > 0) {
  		/* restart */
  		synth->alive = 1;
  		synth_printf("%s", synth->init);
  		return 2; /* reenabled */
  	}
  	pr_warn("%s: can't restart synth\n", synth->long_name);
  	return 0;
  }
  EXPORT_SYMBOL_GPL(spk_synth_is_alive_restart);
  
  static void thread_wake_up(struct timer_list *unused)
  {
  	wake_up_interruptible_all(&speakup_event);
  }
  
  static DEFINE_TIMER(thread_timer, thread_wake_up);
  
  void synth_start(void)
  {
  	struct var_t *trigger_time;
  
  	if (!synth->alive) {
  		synth_buffer_clear();
  		return;
  	}
  	trigger_time = spk_get_var(TRIGGER);
  	if (!timer_pending(&thread_timer))
  		mod_timer(&thread_timer, jiffies +
  			msecs_to_jiffies(trigger_time->u.n.value));
  }
  
  void spk_do_flush(void)
  {
  	if (!synth)
  		return;
  
  	speakup_info.flushing = 1;
  	synth_buffer_clear();
  	if (synth->alive) {
  		if (spk_pitch_shift) {
  			synth_printf("%s", spk_pitch_buff);
  			spk_pitch_shift = 0;
  		}
  	}
  	wake_up_interruptible_all(&speakup_event);
  	wake_up_process(speakup_task);
  }
  
  void synth_write(const char *buf, size_t count)
  {
  	while (count--)
  		synth_buffer_add(*buf++);
  	synth_start();
  }
  
  void synth_printf(const char *fmt, ...)
  {
  	va_list args;
  	unsigned char buf[160], *p;
  	int r;
  
  	va_start(args, fmt);
  	r = vsnprintf(buf, sizeof(buf), fmt, args);
  	va_end(args);
  	if (r > sizeof(buf) - 1)
  		r = sizeof(buf) - 1;
  
  	p = buf;
  	while (r--)
  		synth_buffer_add(*p++);
  	synth_start();
  }
  EXPORT_SYMBOL_GPL(synth_printf);
  
  void synth_putwc(u16 wc)
  {
  	synth_buffer_add(wc);
  }
  EXPORT_SYMBOL_GPL(synth_putwc);
  
  void synth_putwc_s(u16 wc)
  {
  	synth_buffer_add(wc);
  	synth_start();
  }
  EXPORT_SYMBOL_GPL(synth_putwc_s);
  
  void synth_putws(const u16 *buf)
  {
  	const u16 *p;
  
  	for (p = buf; *p; p++)
  		synth_buffer_add(*p);
  }
  EXPORT_SYMBOL_GPL(synth_putws);
  
  void synth_putws_s(const u16 *buf)
  {
  	synth_putws(buf);
  	synth_start();
  }
  EXPORT_SYMBOL_GPL(synth_putws_s);
  
  static int index_count;
  static int sentence_count;
  
  void spk_reset_index_count(int sc)
  {
  	static int first = 1;
  
  	if (first)
  		first = 0;
  	else
  		synth->get_index(synth);
  	index_count = 0;
  	sentence_count = sc;
  }
  
  int synth_supports_indexing(void)
  {
  	if (synth->get_index)
  		return 1;
  	return 0;
  }
  
  void synth_insert_next_index(int sent_num)
  {
  	int out;
  
  	if (synth->alive) {
  		if (sent_num == 0) {
  			synth->indexing.currindex++;
  			index_count++;
  			if (synth->indexing.currindex >
  					synth->indexing.highindex)
  				synth->indexing.currindex =
  					synth->indexing.lowindex;
  		}
  
  		out = synth->indexing.currindex * 10 + sent_num;
  		synth_printf(synth->indexing.command, out, out);
  	}
  }
  
  void spk_get_index_count(int *linecount, int *sentcount)
  {
  	int ind = synth->get_index(synth);
  
  	if (ind) {
  		sentence_count = ind % 10;
  
  		if ((ind / 10) <= synth->indexing.currindex)
  			index_count = synth->indexing.currindex - (ind / 10);
  		else
  			index_count = synth->indexing.currindex
  				- synth->indexing.lowindex
  				+ synth->indexing.highindex - (ind / 10) + 1;
  	}
  	*sentcount = sentence_count;
  	*linecount = index_count;
  }
  
  static struct resource synth_res;
  
  int synth_request_region(unsigned long start, unsigned long n)
  {
  	struct resource *parent = &ioport_resource;
  
  	memset(&synth_res, 0, sizeof(synth_res));
  	synth_res.name = synth->name;
  	synth_res.start = start;
  	synth_res.end = start + n - 1;
  	synth_res.flags = IORESOURCE_BUSY;
  	return request_resource(parent, &synth_res);
  }
  EXPORT_SYMBOL_GPL(synth_request_region);
  
  int synth_release_region(unsigned long start, unsigned long n)
  {
  	return release_resource(&synth_res);
  }
  EXPORT_SYMBOL_GPL(synth_release_region);
  
  struct var_t synth_time_vars[] = {
  	{ DELAY, .u.n = {NULL, 100, 100, 2000, 0, 0, NULL } },
  	{ TRIGGER, .u.n = {NULL, 20, 10, 2000, 0, 0, NULL } },
  	{ JIFFY, .u.n = {NULL, 50, 20, 200, 0, 0, NULL } },
  	{ FULL, .u.n = {NULL, 400, 200, 60000, 0, 0, NULL } },
  	V_LAST_VAR
  };
  
  /* called by: speakup_init() */
  int synth_init(char *synth_name)
  {
  	int ret = 0;
  	struct spk_synth *tmp, *synth = NULL;
  
  	if (!synth_name)
  		return 0;
  
  	if (strcmp(synth_name, "none") == 0) {
  		mutex_lock(&spk_mutex);
  		synth_release();
  		mutex_unlock(&spk_mutex);
  		return 0;
  	}
  
  	mutex_lock(&spk_mutex);
  	/* First, check if we already have it loaded. */
  	list_for_each_entry(tmp, &synths, node) {
  		if (strcmp(tmp->name, synth_name) == 0)
  			synth = tmp;
  	}
  
  	/* If we got one, initialize it now. */
  	if (synth)
  		ret = do_synth_init(synth);
  	else
  		ret = -ENODEV;
  	mutex_unlock(&spk_mutex);
  
  	return ret;
  }
  
  /* called by: synth_add() */
  static int do_synth_init(struct spk_synth *in_synth)
  {
  	struct var_t *var;
  
  	synth_release();
  	if (in_synth->checkval != SYNTH_CHECK)
  		return -EINVAL;
  	synth = in_synth;
  	synth->alive = 0;
  	pr_warn("synth probe\n");
  	if (synth->probe(synth) < 0) {
  		pr_warn("%s: device probe failed\n", in_synth->name);
  		synth = NULL;
  		return -ENODEV;
  	}
  	synth_time_vars[0].u.n.value =
  		synth_time_vars[0].u.n.default_val = synth->delay;
  	synth_time_vars[1].u.n.value =
  		synth_time_vars[1].u.n.default_val = synth->trigger;
  	synth_time_vars[2].u.n.value =
  		synth_time_vars[2].u.n.default_val = synth->jiffies;
  	synth_time_vars[3].u.n.value =
  		synth_time_vars[3].u.n.default_val = synth->full;
  	synth_printf("%s", synth->init);
  	for (var = synth->vars;
  		(var->var_id >= 0) && (var->var_id < MAXVARS); var++)
  		speakup_register_var(var);
  	if (!spk_quiet_boot)
  		synth_printf("%s found\n", synth->long_name);
  	if (synth->attributes.name &&
  	    sysfs_create_group(speakup_kobj, &synth->attributes) < 0)
  		return -ENOMEM;
  	synth_flags = synth->flags;
  	wake_up_interruptible_all(&speakup_event);
  	if (speakup_task)
  		wake_up_process(speakup_task);
  	return 0;
  }
  
  void synth_release(void)
  {
  	struct var_t *var;
  	unsigned long flags;
  
  	if (!synth)
  		return;
  	spin_lock_irqsave(&speakup_info.spinlock, flags);
  	pr_info("releasing synth %s\n", synth->name);
  	synth->alive = 0;
  	del_timer(&thread_timer);
  	spin_unlock_irqrestore(&speakup_info.spinlock, flags);
  	if (synth->attributes.name)
  		sysfs_remove_group(speakup_kobj, &synth->attributes);
  	for (var = synth->vars; var->var_id != MAXVARS; var++)
  		speakup_unregister_var(var->var_id);
  	synth->release();
  	synth = NULL;
  }
  
  /* called by: all_driver_init() */
  int synth_add(struct spk_synth *in_synth)
  {
  	int status = 0;
  	struct spk_synth *tmp;
  
  	mutex_lock(&spk_mutex);
  
  	list_for_each_entry(tmp, &synths, node) {
  		if (tmp == in_synth) {
  			mutex_unlock(&spk_mutex);
  			return 0;
  		}
  	}
  
  	if (in_synth->startup)
  		status = do_synth_init(in_synth);
  
  	if (!status)
  		list_add_tail(&in_synth->node, &synths);
  
  	mutex_unlock(&spk_mutex);
  	return status;
  }
  EXPORT_SYMBOL_GPL(synth_add);
  
  void synth_remove(struct spk_synth *in_synth)
  {
  	mutex_lock(&spk_mutex);
  	if (synth == in_synth)
  		synth_release();
  	list_del(&in_synth->node);
  	module_status = 0;
  	mutex_unlock(&spk_mutex);
  }
  EXPORT_SYMBOL_GPL(synth_remove);
  
  struct spk_synth *synth_current(void)
  {
  	return synth;
  }
  EXPORT_SYMBOL_GPL(synth_current);
  
  short spk_punc_masks[] = { 0, SOME, MOST, PUNC, PUNC | B_SYM };
  