text: // SPDX-License-Identifier: GPL-2.0+
  /*
   * originally written by: Kirk Reiser <kirk@braille.uwo.ca>
   * this version considerably modified by David Borowski, david575@rogers.com
   *
   * Copyright (C) 1998-99  Kirk Reiser.
   * Copyright (C) 2003 David Borowski.
   *
   * specificly written as a driver for the speakup screenreview
   * s not a general device driver.
   */
  #include <linux/unistd.h>
  #include <linux/proc_fs.h>
  #include <linux/jiffies.h>
  #include <linux/spinlock.h>
  #include <linux/sched.h>
  #include <linux/timer.h>
  #include <linux/kthread.h>
  #include "speakup.h"
  #include "spk_priv.h"
  
  #define DRV_VERSION "2.20"
  #define SYNTH_CLEAR 0x03
  #define PROCSPEECH 0x0b
  static int xoff;
  
  static inline int synth_full(void)
  {
  	return xoff;
  }
  
  static void do_catch_up(struct spk_synth *synth);
  static void synth_flush(struct spk_synth *synth);
  static void read_buff_add(u_char c);
  static unsigned char get_index(struct spk_synth *synth);
  
  static int in_escape;
  static int is_flushing;
  
  static spinlock_t flush_lock;
  static DECLARE_WAIT_QUEUE_HEAD(flush);
  
  static struct var_t vars[] = {
  	{ CAPS_START, .u.s = {"[:dv ap 160] " } },
  	{ CAPS_STOP, .u.s = {"[:dv ap 100 ] " } },
  	{ RATE, .u.n = {"[:ra %d] ", 180, 75, 650, 0, 0, NULL } },
  	{ INFLECTION, .u.n = {"[:dv pr %d] ", 100, 0, 10000, 0, 0, NULL } },
  	{ VOL, .u.n = {"[:dv g5 %d] ", 86, 60, 86, 0, 0, NULL } },
  	{ PUNCT, .u.n = {"[:pu %c] ", 0, 0, 2, 0, 0, "nsa" } },
  	{ VOICE, .u.n = {"[:n%c] ", 0, 0, 9, 0, 0, "phfdburwkv" } },
  	{ DIRECT, .u.n = {NULL, 0, 0, 1, 0, 0, NULL } },
  	V_LAST_VAR
  };
  
  /*
   * These attributes will appear in /sys/accessibility/speakup/dectlk.
   */
  static struct kobj_attribute caps_start_attribute =
  	__ATTR(caps_start, 0644, spk_var_show, spk_var_store);
  static struct kobj_attribute caps_stop_attribute =
  	__ATTR(caps_stop, 0644, spk_var_show, spk_var_store);
  static struct kobj_attribute pitch_attribute =
  	__ATTR(pitch, 0644, spk_var_show, spk_var_store);
  static struct kobj_attribute inflection_attribute =
  	__ATTR(inflection, 0644, spk_var_show, spk_var_store);
  static struct kobj_attribute punct_attribute =
  	__ATTR(punct, 0644, spk_var_show, spk_var_store);
  static struct kobj_attribute rate_attribute =
  	__ATTR(rate, 0644, spk_var_show, spk_var_store);
  static struct kobj_attribute voice_attribute =
  	__ATTR(voice, 0644, spk_var_show, spk_var_store);
  static struct kobj_attribute vol_attribute =
  	__ATTR(vol, 0644, spk_var_show, spk_var_store);
  
  static struct kobj_attribute delay_time_attribute =
  	__ATTR(delay_time, 0644, spk_var_show, spk_var_store);
  static struct kobj_attribute direct_attribute =
  	__ATTR(direct, 0644, spk_var_show, spk_var_store);
  static struct kobj_attribute full_time_attribute =
  	__ATTR(full_time, 0644, spk_var_show, spk_var_store);
  static struct kobj_attribute jiffy_delta_attribute =
  	__ATTR(jiffy_delta, 0644, spk_var_show, spk_var_store);
  static struct kobj_attribute trigger_time_attribute =
  	__ATTR(trigger_time, 0644, spk_var_show, spk_var_store);
  
  /*
   * Create a group of attributes so that we can create and destroy them all
   * at once.
   */
  static struct attribute *synth_attrs[] = {
  	&caps_start_attribute.attr,
  	&caps_stop_attribute.attr,
  	&pitch_attribute.attr,
  	&inflection_attribute.attr,
  	&punct_attribute.attr,
  	&rate_attribute.attr,
  	&voice_attribute.attr,
  	&vol_attribute.attr,
  	&delay_time_attribute.attr,
  	&direct_attribute.attr,
  	&full_time_attribute.attr,
  	&jiffy_delta_attribute.attr,
  	&trigger_time_attribute.attr,
  	NULL,	/* need to NULL terminate the list of attributes */
  };
  
  static int ap_defaults[] = {122, 89, 155, 110, 208, 240, 200, 106, 306};
  static int g5_defaults[] = {86, 81, 86, 84, 81, 80, 83, 83, 73};
  
  static struct spk_synth synth_dectlk = {
  	.name = "dectlk",
  	.version = DRV_VERSION,
  	.long_name = "Dectalk Express",
  	.init = "[:error sp :name paul :rate 180 :tsr off] ",
  	.procspeech = PROCSPEECH,
  	.clear = SYNTH_CLEAR,
  	.delay = 500,
  	.trigger = 50,
  	.jiffies = 50,
  	.full = 40000,
  	.dev_name = SYNTH_DEFAULT_DEV,
  	.startup = SYNTH_START,
  	.checkval = SYNTH_CHECK,
  	.vars = vars,
  	.default_pitch = ap_defaults,
  	.default_vol = g5_defaults,
  	.io_ops = &spk_ttyio_ops,
  	.probe = spk_ttyio_synth_probe,
  	.release = spk_ttyio_release,
  	.synth_immediate = spk_ttyio_synth_immediate,
  	.catch_up = do_catch_up,
  	.flush = synth_flush,
  	.is_alive = spk_synth_is_alive_restart,
  	.synth_adjust = NULL,
  	.read_buff_add = read_buff_add,
  	.get_index = get_index,
  	.indexing = {
  		.command = "[:in re %d ] ",
  		.lowindex = 1,
  		.highindex = 8,
  		.currindex = 1,
  	},
  	.attributes = {
  		.attrs = synth_attrs,
  		.name = "dectlk",
  	},
  };
  
  static int is_indnum(u_char *ch)
  {
  	if ((*ch >= '0') && (*ch <= '9')) {
  		*ch = *ch - '0';
  		return 1;
  	}
  	return 0;
  }
  
  static u_char lastind;
  
  static unsigned char get_index(struct spk_synth *synth)
  {
  	u_char rv;
  
  	rv = lastind;
  	lastind = 0;
  	return rv;
  }
  
  static void read_buff_add(u_char c)
  {
  	static int ind = -1;
  
  	if (c == 0x01) {
  		unsigned long flags;
  
  		spin_lock_irqsave(&flush_lock, flags);
  		is_flushing = 0;
  		wake_up_interruptible(&flush);
  		spin_unlock_irqrestore(&flush_lock, flags);
  	} else if (c == 0x13) {
  		xoff = 1;
  	} else if (c == 0x11) {
  		xoff = 0;
  	} else if (is_indnum(&c)) {
  		if (ind == -1)
  			ind = c;
  		else
  			ind = ind * 10 + c;
  	} else if ((c > 31) && (c < 127)) {
  		if (ind != -1)
  			lastind = (u_char)ind;
  		ind = -1;
  	}
  }
  
  static void do_catch_up(struct spk_synth *synth)
  {
  	int synth_full_val = 0;
  	static u_char ch;
  	static u_char last = '\0';
  	unsigned long flags;
  	unsigned long jiff_max;
  	unsigned long timeout = msecs_to_jiffies(4000);
  	DEFINE_WAIT(wait);
  	struct var_t *jiffy_delta;
  	struct var_t *delay_time;
  	int jiffy_delta_val;
  	int delay_time_val;
  
  	jiffy_delta = spk_get_var(JIFFY);
  	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()) {
  		/* if no ctl-a in 4, send data anyway */
  		spin_lock_irqsave(&flush_lock, flags);
  		while (is_flushing && timeout) {
  			prepare_to_wait(&flush, &wait, TASK_INTERRUPTIBLE);
  			spin_unlock_irqrestore(&flush_lock, flags);
  			timeout = schedule_timeout(timeout);
  			spin_lock_irqsave(&flush_lock, flags);
  		}
  		finish_wait(&flush, &wait);
  		is_flushing = 0;
  		spin_unlock_irqrestore(&flush_lock, flags);
  
  		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;
  		}
  		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);
  		delay_time_val = delay_time->u.n.value;
  		synth_full_val = synth_full();
  		spin_unlock_irqrestore(&speakup_info.spinlock, flags);
  		if (ch == '\n')
  			ch = 0x0D;
  		if (synth_full_val || !synth->io_ops->synth_out(synth, ch)) {
  			schedule_timeout(msecs_to_jiffies(delay_time_val));
  			continue;
  		}
  		set_current_state(TASK_RUNNING);
  		spin_lock_irqsave(&speakup_info.spinlock, flags);
  		synth_buffer_getc();
  		spin_unlock_irqrestore(&speakup_info.spinlock, flags);
  		if (ch == '[') {
  			in_escape = 1;
  		} else if (ch == ']') {
  			in_escape = 0;
  		} else if (ch <= SPACE) {
  			if (!in_escape && strchr(",.!?;:", last))
  				synth->io_ops->synth_out(synth, PROCSPEECH);
  			if (time_after_eq(jiffies, jiff_max)) {
  				if (!in_escape)
  					synth->io_ops->synth_out(synth,
  								 PROCSPEECH);
  				spin_lock_irqsave(&speakup_info.spinlock,
  						  flags);
  				jiffy_delta_val = jiffy_delta->u.n.value;
  				delay_time_val = delay_time->u.n.value;
  				spin_unlock_irqrestore(&speakup_info.spinlock,
  						       flags);
  				schedule_timeout(msecs_to_jiffies
  						 (delay_time_val));
  				jiff_max = jiffies + jiffy_delta_val;
  			}
  		}
  		last = ch;
  	}
  	if (!in_escape)
  		synth->io_ops->synth_out(synth, PROCSPEECH);
  }
  
  static void synth_flush(struct spk_synth *synth)
  {
  	if (in_escape)
  		/* if in command output ']' so we don't get an error */
  		synth->io_ops->synth_out(synth, ']');
  	in_escape = 0;
  	is_flushing = 1;
  	synth->io_ops->flush_buffer();
  	synth->io_ops->synth_out(synth, SYNTH_CLEAR);
  }
  
  module_param_named(ser, synth_dectlk.ser, int, 0444);
  module_param_named(dev, synth_dectlk.dev_name, charp, 0444);
  module_param_named(start, synth_dectlk.startup, short, 0444);
  
  MODULE_PARM_DESC(ser, "Set the serial port for the synthesizer (0-based).");
  MODULE_PARM_DESC(dev, "Set the device e.g. ttyUSB0, for the synthesizer.");
  MODULE_PARM_DESC(start, "Start the synthesizer once it is loaded.");
  
  module_spk_synth(synth_dectlk);
  
  MODULE_AUTHOR("Kirk Reiser <kirk@braille.uwo.ca>");
  MODULE_AUTHOR("David Borowski");
  MODULE_DESCRIPTION("Speakup support for DECtalk Express synthesizers");
  MODULE_LICENSE("GPL");
  MODULE_VERSION(DRV_VERSION);
  
  