/*

 * TI TSC2005 emulator.

 *

 * Copyright (c) 2006 Andrzej Zaborowski  <balrog@zabor.org>

 * Copyright (C) 2008 Nokia Corporation

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU General Public License as

 * published by the Free Software Foundation; either version 2 or

 * (at your option) version 3 of the License.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,

 * MA 02111-1307 USA

 */

#include "hw.h"

#include "qemu-timer.h"

#include "console.h"

#include "devices.h"

#define TSC_CUT_RESOLUTION(value, p)	((value) >> (16 - (p ? 12 : 10)))

struct tsc2005_state_s {

    qemu_irq pint;	/* Combination of the nPENIRQ and DAV signals */

    QEMUTimer *timer;

    uint16_t model;

    int x, y;

    int pressure;

    int state, reg, irq, command;

    uint16_t data, dav;

    int busy;

    int enabled;

    int host_mode;

    int function;

    int nextfunction;

    int precision;

    int nextprecision;

    int filter;

    int pin_func;

    int timing[2];

    int noise;

    int reset;

    int pdst;

    int pnd0;

    uint16_t temp_thr[2];

    uint16_t aux_thr[2];

    int tr[8];

};

enum {

    TSC_MODE_XYZ_SCAN	= 0x0,

    TSC_MODE_XY_SCAN,

    TSC_MODE_X,

    TSC_MODE_Y,

    TSC_MODE_Z,

    TSC_MODE_AUX,

    TSC_MODE_TEMP1,

    TSC_MODE_TEMP2,

    TSC_MODE_AUX_SCAN,

    TSC_MODE_X_TEST,

    TSC_MODE_Y_TEST,

    TSC_MODE_TS_TEST,

    TSC_MODE_RESERVED,

    TSC_MODE_XX_DRV,

    TSC_MODE_YY_DRV,

    TSC_MODE_YX_DRV,

};

static const uint16_t mode_regs[16] = {

    0xf000,	/* X, Y, Z scan */

    0xc000,	/* X, Y scan */

    0x8000,	/* X */

    0x4000,	/* Y */

    0x3000,	/* Z */

    0x0800,	/* AUX */

    0x0400,	/* TEMP1 */

    0x0200,	/* TEMP2 */

    0x0800,	/* AUX scan */

    0x0040,	/* X test */

    0x0020,	/* Y test */

    0x0080,	/* Short-circuit test */

    0x0000,	/* Reserved */

    0x0000,	/* X+, X- drivers */

    0x0000,	/* Y+, Y- drivers */

    0x0000,	/* Y+, X- drivers */

};

#define X_TRANSFORM(s)			\

    ((s->y * s->tr[0] - s->x * s->tr[1]) / s->tr[2] + s->tr[3])

#define Y_TRANSFORM(s)			\

    ((s->y * s->tr[4] - s->x * s->tr[5]) / s->tr[6] + s->tr[7])

#define Z1_TRANSFORM(s)			\

    ((400 - ((s)->x >> 7) + ((s)->pressure << 10)) << 4)

#define Z2_TRANSFORM(s)			\

    ((4000 + ((s)->y >> 7) - ((s)->pressure << 10)) << 4)

#define AUX_VAL				(700 << 4)	/* +/- 3 at 12-bit */

#define TEMP1_VAL			(1264 << 4)	/* +/- 5 at 12-bit */

#define TEMP2_VAL			(1531 << 4)	/* +/- 5 at 12-bit */

static uint16_t tsc2005_read(struct tsc2005_state_s *s, int reg)

{

    uint16_t ret;

    switch (reg) {

    case 0x0:	/* X */

        s->dav &= ~mode_regs[TSC_MODE_X];

        return TSC_CUT_RESOLUTION(X_TRANSFORM(s), s->precision) +

                (s->noise & 3);

    case 0x1:	/* Y */

        s->dav &= ~mode_regs[TSC_MODE_Y];

        s->noise ++;

        return TSC_CUT_RESOLUTION(Y_TRANSFORM(s), s->precision) ^

                (s->noise & 3);

    case 0x2:	/* Z1 */

        s->dav &= 0xdfff;

        return TSC_CUT_RESOLUTION(Z1_TRANSFORM(s), s->precision) -

                (s->noise & 3);

    case 0x3:	/* Z2 */

        s->dav &= 0xefff;

        return TSC_CUT_RESOLUTION(Z2_TRANSFORM(s), s->precision) |

                (s->noise & 3);

    case 0x4:	/* AUX */

        s->dav &= ~mode_regs[TSC_MODE_AUX];

        return TSC_CUT_RESOLUTION(AUX_VAL, s->precision);

    case 0x5:	/* TEMP1 */

        s->dav &= ~mode_regs[TSC_MODE_TEMP1];

        return TSC_CUT_RESOLUTION(TEMP1_VAL, s->precision) -

                (s->noise & 5);

    case 0x6:	/* TEMP2 */

        s->dav &= 0xdfff;

        s->dav &= ~mode_regs[TSC_MODE_TEMP2];

        return TSC_CUT_RESOLUTION(TEMP2_VAL, s->precision) ^

                (s->noise & 3);

    case 0x7:	/* Status */

        ret = s->dav | (s->reset << 7) | (s->pdst << 2) | 0x0;

        s->dav &= ~(mode_regs[TSC_MODE_X_TEST] | mode_regs[TSC_MODE_Y_TEST] |

                        mode_regs[TSC_MODE_TS_TEST]);

        s->reset = 1;

        return ret;

    case 0x8:	/* AUX high treshold */

        return s->aux_thr[1];

    case 0x9:	/* AUX low treshold */

        return s->aux_thr[0];

    case 0xa:	/* TEMP high treshold */

        return s->temp_thr[1];

    case 0xb:	/* TEMP low treshold */

        return s->temp_thr[0];

    case 0xc:	/* CFR0 */

        return (s->pressure << 15) | ((!s->busy) << 14) |

                (s->nextprecision << 13) | s->timing[0]; 

    case 0xd:	/* CFR1 */

        return s->timing[1];

    case 0xe:	/* CFR2 */

        return (s->pin_func << 14) | s->filter;

    case 0xf:	/* Function select status */

        return s->function >= 0 ? 1 << s->function : 0;

    }

    /* Never gets here */

    return 0xffff;

}

static void tsc2005_write(struct tsc2005_state_s *s, int reg, uint16_t data)

{

    switch (reg) {

    case 0x8:	/* AUX high treshold */

        s->aux_thr[1] = data;

        break;

    case 0x9:	/* AUX low treshold */

        s->aux_thr[0] = data;

        break;

    case 0xa:	/* TEMP high treshold */

        s->temp_thr[1] = data;

        break;

    case 0xb:	/* TEMP low treshold */

        s->temp_thr[0] = data;

        break;

    case 0xc:	/* CFR0 */

        s->host_mode = data >> 15;

        if (s->enabled != !(data & 0x4000)) {

            s->enabled = !(data & 0x4000);

            fprintf(stderr, "%s: touchscreen sense %sabled\n",

                            __FUNCTION__, s->enabled ? "en" : "dis");

            if (s->busy && !s->enabled)

                qemu_del_timer(s->timer);

            s->busy &= s->enabled;

        }

        s->nextprecision = (data >> 13) & 1;

        s->timing[0] = data & 0x1fff;

        if ((s->timing[0] >> 11) == 3)

            fprintf(stderr, "%s: illegal conversion clock setting\n",

                            __FUNCTION__);

        break;

    case 0xd:	/* CFR1 */

        s->timing[1] = data & 0xf07;

        break;

    case 0xe:	/* CFR2 */

        s->pin_func = (data >> 14) & 3;

        s->filter = data & 0x3fff;

        break;

    default:

        fprintf(stderr, "%s: write into read-only register %x\n",

                        __FUNCTION__, reg);

    }

}

/* This handles most of the chip's logic.  */

static void tsc2005_pin_update(struct tsc2005_state_s *s)

{

    int64_t expires;

    int pin_state;

    switch (s->pin_func) {

    case 0:

        pin_state = !s->pressure && !!s->dav;

        break;

    case 1:

    case 3:

    default:

        pin_state = !s->dav;

        break;

    case 2:

        pin_state = !s->pressure;

    }

    if (pin_state != s->irq) {

        s->irq = pin_state;

        qemu_set_irq(s->pint, s->irq);

    }

    switch (s->nextfunction) {

    case TSC_MODE_XYZ_SCAN:

    case TSC_MODE_XY_SCAN:

        if (!s->host_mode && s->dav)

            s->enabled = 0;

        if (!s->pressure)

            return;

        /* Fall through */

    case TSC_MODE_AUX_SCAN:

        break;

    case TSC_MODE_X:

    case TSC_MODE_Y:

    case TSC_MODE_Z:

        if (!s->pressure)

            return;

        /* Fall through */

    case TSC_MODE_AUX:

    case TSC_MODE_TEMP1:

    case TSC_MODE_TEMP2:

    case TSC_MODE_X_TEST:

    case TSC_MODE_Y_TEST:

    case TSC_MODE_TS_TEST:

        if (s->dav)

            s->enabled = 0;

        break;

    case TSC_MODE_RESERVED:

    case TSC_MODE_XX_DRV:

    case TSC_MODE_YY_DRV:

    case TSC_MODE_YX_DRV:

    default:

        return;

    }

    if (!s->enabled || s->busy)

        return;

    s->busy = 1;

    s->precision = s->nextprecision;

    s->function = s->nextfunction;

    s->pdst = !s->pnd0;	/* Synchronised on internal clock */

    expires = qemu_get_clock(vm_clock) + (ticks_per_sec >> 7);

    qemu_mod_timer(s->timer, expires);

}

static void tsc2005_reset(struct tsc2005_state_s *s)

{

    s->state = 0;

    s->pin_func = 0;

    s->enabled = 0;

    s->busy = 0;

    s->nextprecision = 0;

    s->nextfunction = 0;

    s->timing[0] = 0;

    s->timing[1] = 0;

    s->irq = 0;

    s->dav = 0;

    s->reset = 0;

    s->pdst = 1;

    s->pnd0 = 0;

    s->function = -1;

    s->temp_thr[0] = 0x000;

    s->temp_thr[1] = 0xfff;

    s->aux_thr[0] = 0x000;

    s->aux_thr[1] = 0xfff;

    tsc2005_pin_update(s);

}

static uint8_t tsc2005_txrx_word(void *opaque, uint8_t value)

{

    struct tsc2005_state_s *s = opaque;

    uint32_t ret = 0;

    switch (s->state ++) {

    case 0:

        if (value & 0x80) {

            /* Command */

            if (value & (1 << 1))

                tsc2005_reset(s);

            else {

                s->nextfunction = (value >> 3) & 0xf;

                s->nextprecision = (value >> 2) & 1;

                if (s->enabled != !(value & 1)) {

                    s->enabled = !(value & 1);

                    fprintf(stderr, "%s: touchscreen sense %sabled\n",

                                    __FUNCTION__, s->enabled ? "en" : "dis");

                    if (s->busy && !s->enabled)

                        qemu_del_timer(s->timer);

                    s->busy &= s->enabled;

                }

                tsc2005_pin_update(s);

            }

            s->state = 0;

        } else if (value) {

            /* Data transfer */

            s->reg = (value >> 3) & 0xf;

            s->pnd0 = (value >> 1) & 1;

            s->command = value & 1;

            if (s->command) {

                /* Read */

                s->data = tsc2005_read(s, s->reg);

                tsc2005_pin_update(s);

            } else

                s->data = 0;

        } else

            s->state = 0;

        break;

    case 1:

        if (s->command)

            ret = (s->data >> 8) & 0xff;

        else

            s->data |= value << 8;

        break;

    case 2:

        if (s->command)

            ret = s->data & 0xff;

        else {

            s->data |= value;

            tsc2005_write(s, s->reg, s->data);

            tsc2005_pin_update(s);

        }

        s->state = 0;

        break;

    }

    return ret;

}

uint32_t tsc2005_txrx(void *opaque, uint32_t value, int len)

{

    uint32_t ret = 0;

    len &= ~7;

    while (len > 0) {

        len -= 8;

        ret |= tsc2005_txrx_word(opaque, (value >> len) & 0xff) << len;

    }

    return ret;

}

static void tsc2005_timer_tick(void *opaque)

{

    struct tsc2005_state_s *s = opaque;

    /* Timer ticked -- a set of conversions has been finished.  */

    if (!s->busy)

        return;

    s->busy = 0;

    s->dav |= mode_regs[s->function];

    s->function = -1;

    tsc2005_pin_update(s);

}

static void tsc2005_touchscreen_event(void *opaque,

                int x, int y, int z, int buttons_state)

{

    struct tsc2005_state_s *s = opaque;

    int p = s->pressure;

    if (buttons_state) {

        s->x = x;

        s->y = y;

    }

    s->pressure = !!buttons_state;

    /*

     * Note: We would get better responsiveness in the guest by

     * signaling TS events immediately, but for now we simulate

     * the first conversion delay for sake of correctness.

     */

    if (p != s->pressure)

        tsc2005_pin_update(s);

}

static void tsc2005_save(QEMUFile *f, void *opaque)

{

    struct tsc2005_state_s *s = (struct tsc2005_state_s *) opaque;

    int i;

    qemu_put_be16(f, s->x);

    qemu_put_be16(f, s->y);

    qemu_put_byte(f, s->pressure);

    qemu_put_byte(f, s->state);

    qemu_put_byte(f, s->reg);

    qemu_put_byte(f, s->command);

    qemu_put_byte(f, s->irq);

    qemu_put_be16s(f, &s->dav);

    qemu_put_be16s(f, &s->data);

    qemu_put_timer(f, s->timer);

    qemu_put_byte(f, s->enabled);

    qemu_put_byte(f, s->host_mode);

    qemu_put_byte(f, s->function);

    qemu_put_byte(f, s->nextfunction);

    qemu_put_byte(f, s->precision);

    qemu_put_byte(f, s->nextprecision);

    qemu_put_be16(f, s->filter);

    qemu_put_byte(f, s->pin_func);

    qemu_put_be16(f, s->timing[0]);

    qemu_put_be16(f, s->timing[1]);

    qemu_put_be16s(f, &s->temp_thr[0]);

    qemu_put_be16s(f, &s->temp_thr[1]);

    qemu_put_be16s(f, &s->aux_thr[0]);

    qemu_put_be16s(f, &s->aux_thr[1]);

    qemu_put_be32(f, s->noise);

    qemu_put_byte(f, s->reset);

    qemu_put_byte(f, s->pdst);

    qemu_put_byte(f, s->pnd0);

    for (i = 0; i < 8; i ++)

        qemu_put_be32(f, s->tr[i]);

}

static int tsc2005_load(QEMUFile *f, void *opaque, int version_id)

{

    struct tsc2005_state_s *s = (struct tsc2005_state_s *) opaque;

    int i;

    s->x = qemu_get_be16(f);

    s->y = qemu_get_be16(f);

    s->pressure = qemu_get_byte(f);

    s->state = qemu_get_byte(f);

    s->reg = qemu_get_byte(f);

    s->command = qemu_get_byte(f);

    s->irq = qemu_get_byte(f);

    qemu_get_be16s(f, &s->dav);

    qemu_get_be16s(f, &s->data);

    qemu_get_timer(f, s->timer);

    s->enabled = qemu_get_byte(f);

    s->host_mode = qemu_get_byte(f);

    s->function = qemu_get_byte(f);

    s->nextfunction = qemu_get_byte(f);

    s->precision = qemu_get_byte(f);

    s->nextprecision = qemu_get_byte(f);

    s->filter = qemu_get_be16(f);

    s->pin_func = qemu_get_byte(f);

    s->timing[0] = qemu_get_be16(f);

    s->timing[1] = qemu_get_be16(f);

    qemu_get_be16s(f, &s->temp_thr[0]);

    qemu_get_be16s(f, &s->temp_thr[1]);

    qemu_get_be16s(f, &s->aux_thr[0]);

    qemu_get_be16s(f, &s->aux_thr[1]);

    s->noise = qemu_get_be32(f);

    s->reset = qemu_get_byte(f);

    s->pdst = qemu_get_byte(f);

    s->pnd0 = qemu_get_byte(f);

    for (i = 0; i < 8; i ++)

        s->tr[i] = qemu_get_be32(f);

    s->busy = qemu_timer_pending(s->timer);

    tsc2005_pin_update(s);

    return 0;

}

void *tsc2005_init(qemu_irq pintdav)

{

    struct tsc2005_state_s *s;

    s = (struct tsc2005_state_s *)