// SPDX-License-Identifier: GPL-2.0+
/*
 * This is the DECtalk PC speakup driver
 *
 * Some constants from DEC's DOS driver:
 *      Copyright (c) by Digital Equipment Corp.
 *
 * 386BSD DECtalk PC driver:
 *      Copyright (c) 1996 Brian Buhrow <buhrow@lothlorien.nfbcal.org>
 *
 * Linux DECtalk PC driver:
 *      Copyright (c) 1997 Nicolas Pitre <nico@cam.org>
 *
 * speakup DECtalk PC Internal driver:
 *      Copyright (c) 2003 David Borowski <david575@golden.net>
 *
 * All rights reserved.
 */
#include <linux/jiffies.h>
#include <linux/sched.h>
#include <linux/timer.h>
#include <linux/kthread.h>

#include "spk_priv.h"
#include "speakup.h"

#define MODULE_init             0x0dec  /* module in boot code */
#define MODULE_self_test        0x8800  /* module in self-test */
#define MODULE_reset            0xffff  /* reinit the whole module */

#define MODE_mask               0xf000  /* mode bits in high nibble */
#define MODE_null               0x0000
#define MODE_test               0x2000  /* in testing mode */
#define MODE_status             0x8000
#define STAT_int                0x0001  /* running in interrupt mode */
#define STAT_tr_char            0x0002  /* character data to transmit */
#define STAT_rr_char            0x0004  /* ready to receive char data */
#define STAT_cmd_ready          0x0008  /* ready to accept commands */
#define STAT_dma_ready          0x0010  /* dma command ready */
#define STAT_digitized          0x0020  /* spc in digitized mode */
#define STAT_new_index          0x0040  /* new last index ready */
#define STAT_new_status         0x0080  /* new status posted */
#define STAT_dma_state          0x0100  /* dma state toggle */
#define STAT_index_valid        0x0200  /* indexs are valid */
#define STAT_flushing           0x0400  /* flush in progress */
#define STAT_self_test          0x0800  /* module in self test */
#define MODE_ready              0xc000  /* module ready for next phase */
#define READY_boot              0x0000
#define READY_kernel            0x0001
#define MODE_error              0xf000

#define CMD_mask                0xf000  /* mask for command nibble */
#define CMD_null                0x0000  /* post status */
#define CMD_control             0x1000  /* hard control command */
#define CTRL_mask               0x0F00  /* mask off control nibble */
#define CTRL_data               0x00FF  /* mask to get data byte */
#define CTRL_null               0x0000  /* null control */
#define CTRL_vol_up             0x0100  /* increase volume */
#define CTRL_vol_down           0x0200  /* decrease volume */
#define CTRL_vol_set            0x0300  /* set volume */
#define CTRL_pause              0x0400  /* pause spc */
#define CTRL_resume             0x0500  /* resume spc clock */
#define CTRL_resume_spc         0x0001  /* resume spc soft pause */
#define CTRL_flush              0x0600  /* flush all buffers */
#define CTRL_int_enable         0x0700  /* enable status change ints */
#define CTRL_buff_free          0x0800  /* buffer remain count */
#define CTRL_buff_used          0x0900  /* buffer in use */
#define CTRL_speech             0x0a00  /* immediate speech change */
#define CTRL_SP_voice           0x0001  /* voice change */
#define CTRL_SP_rate            0x0002  /* rate change */
#define CTRL_SP_comma           0x0003  /* comma pause change */
#define CTRL_SP_period          0x0004  /* period pause change */
#define CTRL_SP_rate_delta      0x0005  /* delta rate change */
#define CTRL_SP_get_param       0x0006  /* return the desired parameter */
#define CTRL_last_index         0x0b00  /* get last index spoken */
#define CTRL_io_priority        0x0c00  /* change i/o priority */
#define CTRL_free_mem           0x0d00  /* get free paragraphs on module */
#define CTRL_get_lang           0x0e00  /* return bitmask of loaded languages */
#define CMD_test                0x2000  /* self-test request */
#define TEST_mask               0x0F00  /* isolate test field */
#define TEST_null               0x0000  /* no test requested */
#define TEST_isa_int            0x0100  /* assert isa irq */
#define TEST_echo               0x0200  /* make data in == data out */
#define TEST_seg                0x0300  /* set peek/poke segment */
#define TEST_off                0x0400  /* set peek/poke offset */
#define TEST_peek               0x0500  /* data out == *peek */
#define TEST_poke               0x0600  /* *peek == data in */
#define TEST_sub_code           0x00FF  /* user defined test sub codes */
#define CMD_id                  0x3000  /* return software id */
#define ID_null                 0x0000  /* null id */
#define ID_kernel               0x0100  /* kernel code executing */
#define ID_boot                 0x0200  /* boot code executing */
#define CMD_dma                 0x4000  /* force a dma start */
#define CMD_reset               0x5000  /* reset module status */
#define CMD_sync                0x6000  /* kernel sync command */
#define CMD_char_in             0x7000  /* single character send */
#define CMD_char_out            0x8000  /* single character get */
#define CHAR_count_1            0x0100  /* one char in cmd_low */
#define CHAR_count_2            0x0200  /* the second in data_low */
#define CHAR_count_3            0x0300  /* the third in data_high */
#define CMD_spc_mode            0x9000  /* change spc mode */
#define CMD_spc_to_text         0x0100  /* set to text mode */
#define CMD_spc_to_digit        0x0200  /* set to digital mode */
#define CMD_spc_rate            0x0400  /* change spc data rate */
#define CMD_error               0xf000  /* severe error */

enum {  PRIMARY_DIC     = 0, USER_DIC, COMMAND_DIC, ABBREV_DIC };

#define DMA_single_in           0x01
#define DMA_single_out          0x02
#define DMA_buff_in             0x03
#define DMA_buff_out            0x04
#define DMA_control             0x05
#define DT_MEM_ALLOC            0x03
#define DT_SET_DIC              0x04
#define DT_START_TASK           0x05
#define DT_LOAD_MEM             0x06
#define DT_READ_MEM             0x07
#define DT_DIGITAL_IN           0x08
#define DMA_sync                0x06
#define DMA_sync_char           0x07

#define DRV_VERSION "2.12"
#define PROCSPEECH 0x0b
#define SYNTH_IO_EXTENT 8

static int synth_probe(struct spk_synth *synth);
static void dtpc_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_portlist[] = { 0x340, 0x350, 0x240, 0x250, 0 };
static int in_escape, is_flushing;
static int dt_stat, dma_state;


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



static struct var_t vars[NB_ID] = {
        [CAPS_START_ID] = { CAPS_START, .u.s = {"[:dv ap 200]" } },
        [CAPS_STOP_ID] = { CAPS_STOP, .u.s = {"[:dv ap 100]" } },
        [RATE_ID] = { RATE, .u.n = {"[:ra %d]", 9, 0, 18, 150, 25, NULL } },
        [PITCH_ID] = { PITCH, .u.n = {"[:dv ap %d]", 80, 0, 100, 20, 0, NULL } },
        [INFLECTION_ID] = { INFLECTION, .u.n = {"[:dv pr %d] ", 100, 0, 10000, 0, 0, NULL } },
        [VOL_ID] = { VOL, .u.n = {"[:vo se %d]", 5, 0, 9, 5, 10, NULL } },
        [PUNCT_ID] = { PUNCT, .u.n = {"[:pu %c]", 0, 0, 2, 0, 0, "nsa" } },
        [VOICE_ID] = { VOICE, .u.n = {"[:n%c]", 0, 0, 9, 0, 0, "phfdburwkv" } },
        [DIRECT_ID] = { DIRECT, .u.n = {NULL, 0, 0, 1, 0, 0, NULL } },
        V_LAST_VAR
};

/*
 * These attributes will appear in /sys/accessibility/speakup/decpc.
 */
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 struct spk_synth synth_dec_pc = {
        .name = "decpc",
        .version = DRV_VERSION,
        .long_name = "Dectalk PC",
        .init = "[:pe -380]",
        .procspeech = PROCSPEECH,
        .delay = 500,
        .trigger = 50,
        .jiffies = 50,
        .full = 1000,
        .flags = SF_DEC,
        .startup = SYNTH_START,
        .checkval = SYNTH_CHECK,
        .vars = vars,
        .io_ops = &spk_serial_io_ops,
        .probe = synth_probe,
        .release = dtpc_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 = NULL,
        .indexing = {
                .command = NULL,
                .lowindex = 0,
                .highindex = 0,
                .currindex = 0,
        },
        .attributes = {
                .attrs = synth_attrs,
                .name = "decpc",
        },
};

static int dt_getstatus(void)
{
        dt_stat = inb_p(speakup_info.port_tts) |
                 (inb_p(speakup_info.port_tts + 1) << 8);
        return dt_stat;
}

static void dt_sendcmd(u_int cmd)
{
        outb_p(cmd & 0xFF, speakup_info.port_tts);
        outb_p((cmd >> 8) & 0xFF, speakup_info.port_tts + 1);
}

static int dt_waitbit(int bit)
{
        int timeout = 100;

        while (--timeout > 0) {
                if ((dt_getstatus() & bit) == bit)
                        return 1;
                udelay(50);
        }
        return 0;
}

static int dt_wait_dma(void)
{
        int timeout = 100, state = dma_state;

        if (!dt_waitbit(STAT_dma_ready))
                return 0;
        while (--timeout > 0) {
                if ((dt_getstatus() & STAT_dma_state) == state)
                        return 1;
                udelay(50);
        }
        dma_state = dt_getstatus() & STAT_dma_state;
        return 1;
}

static int dt_ctrl(u_int cmd)
{
        int timeout = 10;

        if (!dt_waitbit(STAT_cmd_ready))
                return -1;
        outb_p(0, speakup_info.port_tts + 2);
        outb_p(0, speakup_info.port_tts + 3);
        dt_getstatus();
        dt_sendcmd(CMD_control | cmd);
        outb_p(0, speakup_info.port_tts + 6);
        while (dt_getstatus() & STAT_cmd_ready) {
                udelay(20);
                if (--timeout == 0)
                        break;
        }
        dt_sendcmd(CMD_null);
        return 0;
}

static void synth_flush(struct spk_synth *synth)
{
        int timeout = 10;

        if (is_flushing)
                return;
        is_flushing = 4;
        in_escape = 0;
        while (dt_ctrl(CTRL_flush)) {
                if (--timeout == 0)
                        break;
                udelay(50);
        }
        for (timeout = 0; timeout < 10; timeout++) {
                if (dt_waitbit(STAT_dma_ready))
                        break;
                udelay(50);
        }
        outb_p(DMA_sync, speakup_info.port_tts + 4);
        outb_p(0, speakup_info.port_tts + 4);
        udelay(100);
        for (timeout = 0; timeout < 10; timeout++) {
                if (!(dt_getstatus() & STAT_flushing))
                        break;
                udelay(50);
        }
        dma_state = dt_getstatus() & STAT_dma_state;
        dma_state ^= STAT_dma_state;
        is_flushing = 0;
}

static int dt_sendchar(char ch)
{
        if (!dt_wait_dma())
                return -1;
        if (!(dt_stat & STAT_rr_char))
                return -2;
        outb_p(DMA_single_in, speakup_info.port_tts + 4);
        outb_p(ch, speakup_info.port_tts + 4);
        dma_state ^= STAT_dma_state;
        return 0;
}

static int testkernel(void)
{
        int status = 0;

        if (dt_getstatus() == 0xffff) {
                status = -1;
                goto oops;
        }
        dt_sendcmd(CMD_sync);
        if (!dt_waitbit(STAT_cmd_ready))
                status = -2;
        else if (dt_stat & 0x8000)
                return 0;
        else if (dt_stat == 0x0dec)
                pr_warn("dec_pc at 0x%x, software not loaded\n",
                        speakup_info.port_tts);
        status = -3;
oops:   synth_release_region(speakup_info.port_tts, SYNTH_IO_EXTENT);
        speakup_info.port_tts = 0;
        return status;
}

static void do_catch_up(struct spk_synth *synth)
{
        u_char ch;
        static u_char last;
        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;
                }
                ch = synth_buffer_peek();
                set_current_state(TASK_INTERRUPTIBLE);
                delay_time_val = delay_time->u.n.value;
                spin_unlock_irqrestore(&speakup_info.spinlock, flags);
                if (ch == '\n')
                        ch = 0x0D;
                if (dt_sendchar(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))
                                dt_sendchar(PROCSPEECH);
                        if (time_after_eq(jiffies, jiff_max)) {
                                if (!in_escape)
                                        dt_sendchar(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;
                ch = 0;
        }
        if (!in_escape)
                dt_sendchar(PROCSPEECH);
}

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

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

static int synth_probe(struct spk_synth *synth)
{
        int i = 0, failed = 0;

        pr_info("Probing for %s.\n", synth->long_name);
        for (i = 0; synth_portlist[i]; i++) {
                if (synth_request_region(synth_portlist[i], SYNTH_IO_EXTENT)) {
                        pr_warn("request_region: failed with 0x%x, %d\n",
                                synth_portlist[i], SYNTH_IO_EXTENT);
                        continue;
                }
                speakup_info.port_tts = synth_portlist[i];
                failed = testkernel();
                if (failed == 0)
                        break;
        }
        if (failed) {
                pr_info("%s: not found\n", synth->long_name);
                return -ENODEV;
        }
        pr_info("%s: %03x-%03x, Driver Version %s,\n", synth->long_name,
                speakup_info.port_tts, speakup_info.port_tts + 7,
                synth->version);
        synth->alive = 1;
        return 0;
}

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

module_param_named(start, synth_dec_pc.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(inflection, vars[INFLECTION_ID].u.n.default_val, int, 0444);
module_param_named(vol, vars[VOL_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(direct, vars[DIRECT_ID].u.n.default_val, int, 0444);




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(inflection, "Set the inflection variable on load.");
MODULE_PARM_DESC(vol, "Set the vol 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(direct, "Set the direct variable on load.");

module_spk_synth(synth_dec_pc);

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