// 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.
 *
 * specifically written as a driver for the speakup screenreview
 * package it's not a general device driver.
 * This driver is for the RC Systems DoubleTalk PC internal synthesizer.
 */
#include <linux/jiffies.h>
#include <linux/sched.h>
#include <linux/timer.h>
#include <linux/kthread.h>

#include "spk_priv.h"
#include "serialio.h"
#include "speakup_dtlk.h" /* local header file for DoubleTalk values */
#include "speakup.h"

#define DRV_VERSION "2.10"
#define PROCSPEECH 0x00

static int synth_probe(struct spk_synth *synth);
static void dtlk_release(struct spk_synth *synth);
static const char *synth_immediate(struct spk_synth *synth, const char *buf);
static void do_catch_up(struct spk_synth *synth);
static void synth_flush(struct spk_synth *synth);

static int synth_lpc;
static int port_forced;
static unsigned int synth_portlist[] = {
                 0x25e, 0x29e, 0x2de, 0x31e, 0x35e, 0x39e, 0
};

static u_char synth_status;

enum default_vars_id {
        CAPS_START_ID = 0, CAPS_STOP_ID,
        RATE_ID, PITCH_ID,
        VOL_ID, TONE_ID, PUNCT_ID,
        VOICE_ID, FREQUENCY_ID,
        DIRECT_ID, V_LAST_VAR_ID,
        NB_ID,
};


static struct var_t vars[NB_ID] = {
        [CAPS_START_ID] = { CAPS_START, .u.s = {"\x01+35p" } },
        [CAPS_STOP_ID] = { CAPS_STOP, .u.s = {"\x01-35p" } },
        [RATE_ID] = { RATE, .u.n = {"\x01%ds", 8, 0, 9, 0, 0, NULL } },
        [PITCH_ID] = { PITCH, .u.n = {"\x01%dp", 50, 0, 99, 0, 0, NULL } },
        [VOL_ID] = { VOL, .u.n = {"\x01%dv", 5, 0, 9, 0, 0, NULL } },
        [TONE_ID] = { TONE, .u.n = {"\x01%dx", 1, 0, 2, 0, 0, NULL } },
        [PUNCT_ID] = { PUNCT, .u.n = {"\x01%db", 7, 0, 15, 0, 0, NULL } },
        [VOICE_ID] = { VOICE, .u.n = {"\x01%do", 0, 0, 7, 0, 0, NULL } },
        [FREQUENCY_ID] = { FREQUENCY, .u.n = {"\x01%df", 5, 0, 9, 0, 0, NULL } },
        [DIRECT_ID] = { DIRECT, .u.n = {NULL, 0, 0, 1, 0, 0, NULL } },
        V_LAST_VAR
};

/*
 * These attributes will appear in /sys/accessibility/speakup/dtlk.
 */
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 freq_attribute =
        __ATTR(freq, 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 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 tone_attribute =
        __ATTR(tone, 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,
        &freq_attribute.attr,
        &pitch_attribute.attr,
        &punct_attribute.attr,
        &rate_attribute.attr,
        &tone_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 struct spk_synth synth_dtlk = {
        .name = "dtlk",
        .version = DRV_VERSION,
        .long_name = "DoubleTalk PC",
        .init = "\x01@\x01\x31y",
        .procspeech = PROCSPEECH,
        .clear = SYNTH_CLEAR,
        .delay = 500,
        .trigger = 30,
        .jiffies = 50,
        .full = 1000,
        .startup = SYNTH_START,
        .checkval = SYNTH_CHECK,
        .vars = vars,
        .io_ops = &spk_serial_io_ops,
        .probe = synth_probe,
        .release = dtlk_release,
        .synth_immediate = synth_immediate,
        .catch_up = do_catch_up,
        .flush = synth_flush,
        .is_alive = spk_synth_is_alive_nop,
        .synth_adjust = NULL,
        .read_buff_add = NULL,
        .get_index = spk_synth_get_index,
        .indexing = {
                .command = "\x01%di",
                .lowindex = 1,
                .highindex = 5,
                .currindex = 1,
        },
        .attributes = {
                .attrs = synth_attrs,
                .name = "dtlk",
        },
};

static inline bool synth_readable(void)
{
        synth_status = inb_p(speakup_info.port_tts + UART_RX);
        return (synth_status & TTS_READABLE) != 0;
}

static inline bool synth_writable(void)
{
        synth_status = inb_p(speakup_info.port_tts + UART_RX);
        return (synth_status & TTS_WRITABLE) != 0;
}

static inline bool synth_full(void)
{
        synth_status = inb_p(speakup_info.port_tts + UART_RX);
        return (synth_status & TTS_ALMOST_FULL) != 0;
}

static void spk_out(const char ch)
{
        int timeout = SPK_XMITR_TIMEOUT;

        while (!synth_writable()) {
                if (!--timeout)
                        break;
                udelay(1);
        }
        outb_p(ch, speakup_info.port_tts);
        timeout = SPK_XMITR_TIMEOUT;
        while (synth_writable()) {
                if (!--timeout)
                        break;
                udelay(1);
        }
}

static void do_catch_up(struct spk_synth *synth)
{
        u_char ch;
        unsigned long flags;
        unsigned long jiff_max;
        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()) {
                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;
                }
                set_current_state(TASK_INTERRUPTIBLE);
                delay_time_val = delay_time->u.n.value;
                spin_unlock_irqrestore(&speakup_info.spinlock, flags);
                if (synth_full()) {
                        schedule_timeout(msecs_to_jiffies(delay_time_val));
                        continue;
                }
                set_current_state(TASK_RUNNING);
                spin_lock_irqsave(&speakup_info.spinlock, flags);
                ch = synth_buffer_getc();
                spin_unlock_irqrestore(&speakup_info.spinlock, flags);
                if (ch == '\n')
                        ch = PROCSPEECH;
                spk_out(ch);
                if (time_after_eq(jiffies, jiff_max) && (ch == SPACE)) {
                        spk_out(PROCSPEECH);
                        spin_lock_irqsave(&speakup_info.spinlock, flags);
                        delay_time_val = delay_time->u.n.value;
                        jiffy_delta_val = jiffy_delta->u.n.value;
                        spin_unlock_irqrestore(&speakup_info.spinlock, flags);
                        schedule_timeout(msecs_to_jiffies(delay_time_val));
                        jiff_max = jiffies + jiffy_delta_val;
                }
        }
        spk_out(PROCSPEECH);
}

static const char *synth_immediate(struct spk_synth *synth, const char *buf)
{
        u_char ch;

        while ((ch = (u_char)*buf)) {
                if (synth_full())
                        return buf;
                if (ch == '\n')
                        ch = PROCSPEECH;
                spk_out(ch);
                buf++;
        }
        return NULL;
}

static void synth_flush(struct spk_synth *synth)
{
        outb_p(SYNTH_CLEAR, speakup_info.port_tts);
        while (synth_writable())
                cpu_relax();
}

static char synth_read_tts(void)
{
        u_char ch;

        while (!synth_readable())
                cpu_relax();
        ch = synth_status & 0x7f;
        outb_p(ch, speakup_info.port_tts);
        while (synth_readable())
                cpu_relax();
        return (char)ch;
}

/* interrogate the DoubleTalk PC and return its settings */
static struct synth_settings *synth_interrogate(struct spk_synth *synth)
{
        u_char *t;
        static char buf[sizeof(struct synth_settings) + 1];
        int total, i;
        static struct synth_settings status;

        synth_immediate(synth, "\x18\x01?");
        for (total = 0, i = 0; i < 50; i++) {
                buf[total] = synth_read_tts();
                if (total > 2 && buf[total] == 0x7f)
                        break;
                if (total < sizeof(struct synth_settings))
                        total++;
        }
        t = buf;
        /* serial number is little endian */
        status.serial_number = t[0] + t[1] * 256;
        t += 2;
        for (i = 0; *t != '\r'; t++) {
                status.rom_version[i] = *t;
                if (i < sizeof(status.rom_version) - 1)
                        i++;
        }
        status.rom_version[i] = 0;
        t++;
        status.mode = *t++;
        status.punc_level = *t++;
        status.formant_freq = *t++;
        status.pitch = *t++;
        status.speed = *t++;
        status.volume = *t++;
        status.tone = *t++;
        status.expression = *t++;
        status.ext_dict_loaded = *t++;
        status.ext_dict_status = *t++;
        status.free_ram = *t++;
        status.articulation = *t++;
        status.reverb = *t++;
        status.eob = *t++;
        return &status;
}

static int synth_probe(struct spk_synth *synth)
{
        unsigned int port_val = 0;
        int i;
        struct synth_settings *sp;

        pr_info("Probing for DoubleTalk.\n");
        if (port_forced) {
                speakup_info.port_tts = port_forced;
                pr_info("probe forced to %x by kernel command line\n",
                        speakup_info.port_tts);
                if ((port_forced & 0xf) != 0xf)
                        pr_info("warning: port base should probably end with f\n");
                if (synth_request_region(speakup_info.port_tts - 1,
                                         SYNTH_IO_EXTENT)) {
                        pr_warn("sorry, port already reserved\n");
                        return -EBUSY;
                }
                port_val = inw(speakup_info.port_tts - 1);
                synth_lpc = speakup_info.port_tts - 1;
        } else {
                for (i = 0; synth_portlist[i]; i++) {
                        if (synth_request_region(synth_portlist[i],
                                                 SYNTH_IO_EXTENT))
                                continue;
                        port_val = inw(synth_portlist[i]) & 0xfbff;
                        if (port_val == 0x107f) {
                                synth_lpc = synth_portlist[i];
                                speakup_info.port_tts = synth_lpc + 1;
                                break;
                        }
                        synth_release_region(synth_portlist[i],
                                             SYNTH_IO_EXTENT);
                }
        }
        port_val &= 0xfbff;
        if (port_val != 0x107f) {
                pr_info("DoubleTalk PC: not found\n");
                if (synth_lpc)
                        synth_release_region(synth_lpc, SYNTH_IO_EXTENT);
                return -ENODEV;
        }
        while (inw_p(synth_lpc) != 0x147f)
                cpu_relax(); /* wait until it's ready */
        sp = synth_interrogate(synth);
        pr_info("%s: %03x-%03x, ROM ver %s, s/n %u, driver: %s\n",
                synth->long_name, synth_lpc, synth_lpc + SYNTH_IO_EXTENT - 1,
                sp->rom_version, sp->serial_number, synth->version);
        synth->alive = 1;
        return 0;
}

static void dtlk_release(struct spk_synth *synth)
{
        spk_stop_serial_interrupt();
        if (speakup_info.port_tts)
                synth_release_region(speakup_info.port_tts - 1,
                                     SYNTH_IO_EXTENT);
        speakup_info.port_tts = 0;
}

module_param_hw_named(port, port_forced, int, ioport, 0444);
module_param_named(start, synth_dtlk.startup, short, 0444);
module_param_named(rate, vars[RATE_ID].u.n.default_val, int, 0444);
module_param_named(pitch, vars[PITCH_ID].u.n.default_val, int, 0444);
module_param_named(vol, vars[VOL_ID].u.n.default_val, int, 0444);
module_param_named(tone, vars[TONE_ID].u.n.default_val, int, 0444);
module_param_named(punct, vars[PUNCT_ID].u.n.default_val, int, 0444);
module_param_named(voice, vars[VOICE_ID].u.n.default_val, int, 0444);
module_param_named(frequency, vars[FREQUENCY_ID].u.n.default_val, int, 0444);
module_param_named(direct, vars[DIRECT_ID].u.n.default_val, int, 0444);


MODULE_PARM_DESC(port, "Set the port for the synthesizer (override probing).");
MODULE_PARM_DESC(start, "Start the synthesizer once it is loaded.");
MODULE_PARM_DESC(rate, "Set the rate variable on load.");
MODULE_PARM_DESC(pitch, "Set the pitch variable on load.");
MODULE_PARM_DESC(vol, "Set the vol variable on load.");
MODULE_PARM_DESC(tone, "Set the tone variable on load.");
MODULE_PARM_DESC(punct, "Set the punct variable on load.");
MODULE_PARM_DESC(voice, "Set the voice variable on load.");
MODULE_PARM_DESC(frequency, "Set the frequency variable on load.");
MODULE_PARM_DESC(direct, "Set the direct variable on load.");


module_spk_synth(synth_dtlk);

MODULE_AUTHOR("Kirk Reiser <kirk@braille.uwo.ca>");
MODULE_AUTHOR("David Borowski");
MODULE_DESCRIPTION("Speakup support for DoubleTalk PC synthesizers");
MODULE_LICENSE("GPL");
MODULE_VERSION(DRV_VERSION);