/*

 * SSD0303 OLED controller with OSRAM Pictiva 96x16 display.

 *

 * Copyright (c) 2006-2007 CodeSourcery.

 * Written by Paul Brook

 *

 * This code is licenced under the GPL.

 */

/* The controller can support a variety of different displays, but we only

   implement one.  Most of the commends relating to brightness and geometry

   setup are ignored. */

#include "hw.h"

#include "i2c.h"

#include "gui.h"

//#define DEBUG_SSD0303 1

#ifdef DEBUG_SSD0303

#define DPRINTF(fmt, args...) \

do { printf("ssd0303: " fmt , ##args); } while (0)

#define BADF(fmt, args...) \

do { fprintf(stderr, "ssd0303: error: " fmt , ##args); exit(1);} while (0)

#else

#define DPRINTF(fmt, args...) do {} while(0)

#define BADF(fmt, args...) \

do { fprintf(stderr, "ssd0303: error: " fmt , ##args);} while (0)

#endif

/* Scaling factor for pixels.  */

#define MAGNIFY 4

enum ssd0303_mode

{

    SSD0303_IDLE,

    SSD0303_DATA,

    SSD0303_CMD

};

enum ssd0303_cmd {

    SSD0303_CMD_NONE,

    SSD0303_CMD_SKIP1

};

typedef struct {

    i2c_slave i2c;

    DisplayState *ds;

    int row;

    int col;

    int start_line;

    int mirror;

    int flash;

    int enabled;

    int inverse;

    int redraw;

    enum ssd0303_mode mode;

    enum ssd0303_cmd cmd_state;

    uint8_t framebuffer[132*8];

} ssd0303_state;

static int ssd0303_recv(i2c_slave *i2c)

{

    BADF("Reads not implemented\n");

    return -1;

}

static int ssd0303_send(i2c_slave *i2c, uint8_t data)

{

    ssd0303_state *s = (ssd0303_state *)i2c;

    enum ssd0303_cmd old_cmd_state;

    switch (s->mode) {

    case SSD0303_IDLE:

        DPRINTF("byte 0x%02x\n", data);

        if (data == 0x80)

            s->mode = SSD0303_CMD;

        else if (data == 0x40)

            s->mode = SSD0303_DATA;

        else

            BADF("Unexpected byte 0x%x\n", data);

        break;

    case SSD0303_DATA:

        DPRINTF("data 0x%02x\n", data);

        if (s->col < 132) {

            s->framebuffer[s->col + s->row * 132] = data;

            s->col++;

            s->redraw = 1;

        }

        break;

    case SSD0303_CMD:

        old_cmd_state = s->cmd_state;

        s->cmd_state = SSD0303_CMD_NONE;

        switch (old_cmd_state) {

        case SSD0303_CMD_NONE:

            DPRINTF("cmd 0x%02x\n", data);

            s->mode = SSD0303_IDLE;

            switch (data) {

            case 0x00 ... 0x0f: /* Set lower colum address.  */

                s->col = (s->col & 0xf0) | (data & 0xf);

                break;

            case 0x10 ... 0x20: /* Set higher column address.  */

                s->col = (s->col & 0x0f) | ((data & 0xf) << 4);

                break;

            case 0x40 ... 0x7f: /* Set start line.  */

                s->start_line = 0;

                break;

            case 0x81: /* Set contrast (Ignored).  */

                s->cmd_state = SSD0303_CMD_SKIP1;

                break;

            case 0xa0: /* Mirror off.  */

                s->mirror = 0;

                break;

            case 0xa1: /* Mirror off.  */

                s->mirror = 1;

                break;

            case 0xa4: /* Entire display off.  */

                s->flash = 0;

                break;

            case 0xa5: /* Entire display on.  */

                s->flash = 1;

                break;

            case 0xa6: /* Inverse off.  */

                s->inverse = 0;

                break;

            case 0xa7: /* Inverse on.  */

                s->inverse = 1;

                break;

            case 0xa8: /* Set multipled ratio (Ignored).  */

                s->cmd_state = SSD0303_CMD_SKIP1;

                break;

            case 0xad: /* DC-DC power control.  */

                s->cmd_state = SSD0303_CMD_SKIP1;

                break;

            case 0xae: /* Display off.  */

                s->enabled = 0;

                break;

            case 0xaf: /* Display on.  */

                s->enabled = 1;

                break;

            case 0xb0 ... 0xbf: /* Set Page address.  */

                s->row = data & 7;

                break;

            case 0xc0 ... 0xc8: /* Set COM output direction (Ignored).  */

                break;

            case 0xd3: /* Set display offset (Ignored).  */

                s->cmd_state = SSD0303_CMD_SKIP1;

                break;

            case 0xd5: /* Set display clock (Ignored).  */

                s->cmd_state = SSD0303_CMD_SKIP1;

                break;

            case 0xd8: /* Set color and power mode (Ignored).  */

                s->cmd_state = SSD0303_CMD_SKIP1;

                break;

            case 0xd9: /* Set pre-charge period (Ignored).  */

                s->cmd_state = SSD0303_CMD_SKIP1;

                break;

            case 0xda: /* Set COM pin configuration (Ignored).  */

                s->cmd_state = SSD0303_CMD_SKIP1;

                break;

            case 0xdb: /* Set VCOM dselect level (Ignored).  */

                s->cmd_state = SSD0303_CMD_SKIP1;

                break;

            case 0xe3: /* no-op.  */

                break;

            default:

                BADF("Unknown command: 0x%x\n", data);

            }

            break;

        case SSD0303_CMD_SKIP1:

            DPRINTF("skip 0x%02x\n", data);

            break;

        }

        break;

    }

    return 0;

}

static void ssd0303_event(i2c_slave *i2c, enum i2c_event event)

{

    ssd0303_state *s = (ssd0303_state *)i2c;

    switch (event) {

    case I2C_FINISH:

        s->mode = SSD0303_IDLE;

        break;

    case I2C_START_RECV:

    case I2C_START_SEND:

    case I2C_NACK:

        /* Nothing to do.  */

        break;

    }

}

static void ssd0303_update_display(void *opaque)

{

    ssd0303_state *s = (ssd0303_state *)opaque;

    uint8_t *dest;

    uint8_t *src;

    int x;

    int y;

    int line;

    char *colors[2];

    char colortab[MAGNIFY * 8];

    int dest_width;

    uint8_t mask;

    if (!s->redraw)

        return;

    switch (ds_get_bits_per_pixel(s->ds)) {

    case 0:

        return;

    case 15:

        dest_width = 2;

        break;

    case 16:

        dest_width = 2;

        break;

    case 24:

        dest_width = 3;

        break;

    case 32:

        dest_width = 4;

        break;

    default:

        BADF("Bad color depth\n");

        return;

    }

    dest_width *= MAGNIFY;

    memset(colortab, 0xff, dest_width);

    memset(colortab + dest_width, 0, dest_width);

    if (s->flash) {

        colors[0] = colortab;

        colors[1] = colortab;

    } else if (s->inverse) {

        colors[0] = colortab;

        colors[1] = colortab + dest_width;

    } else {

        colors[0] = colortab + dest_width;

        colors[1] = colortab;

    }

    dest = ds_get_data(s->ds);

    for (y = 0; y < 16; y++) {

        line = (y + s->start_line) & 63;

        src = s->framebuffer + 132 * (line >> 3) + 36;

        mask = 1 << (line & 7);

        for (x = 0; x < 96; x++) {

            memcpy(dest, colors[(*src & mask) != 0], dest_width);

            dest += dest_width;

            src++;

        }

        for (x = 1; x < MAGNIFY; x++) {

            memcpy(dest, dest - dest_width * 96, dest_width * 96);

            dest += dest_width * 96;

        }

    }

    s->redraw = 0;

    dpy_update(s->ds, 0, 0, 96 * MAGNIFY, 16 * MAGNIFY);

}

static void ssd0303_invalidate_display(void * opaque)

{

    ssd0303_state *s = (ssd0303_state *)opaque;

    s->redraw = 1;

}

static void ssd0303_save(QEMUFile *f, void *opaque)

{

    ssd0303_state *s = (ssd0303_state *)opaque;

    qemu_put_be32(f, s->row);

    qemu_put_be32(f, s->col);

    qemu_put_be32(f, s->start_line);

    qemu_put_be32(f, s->mirror);

    qemu_put_be32(f, s->flash);

    qemu_put_be32(f, s->enabled);

    qemu_put_be32(f, s->inverse);

    qemu_put_be32(f, s->redraw);

    qemu_put_be32(f, s->mode);

    qemu_put_be32(f, s->cmd_state);

    qemu_put_buffer(f, s->framebuffer, sizeof(s->framebuffer));

    i2c_slave_save(f, &s->i2c);

}

static int ssd0303_load(QEMUFile *f, void *opaque, int version_id)

{

    ssd0303_state *s = (ssd0303_state *)opaque;

    if (version_id != 1)

        return -EINVAL;

    s->row = qemu_get_be32(f);

    s->col = qemu_get_be32(f);

    s->start_line = qemu_get_be32(f);

    s->mirror = qemu_get_be32(f);

    s->flash = qemu_get_be32(f);

    s->enabled = qemu_get_be32(f);

    s->inverse = qemu_get_be32(f);

    s->redraw = qemu_get_be32(f);

    s->mode = qemu_get_be32(f);

    s->cmd_state = qemu_get_be32(f);

    qemu_get_buffer(f, s->framebuffer, sizeof(s->framebuffer));

    i2c_slave_load(f, &s->i2c);

    return 0;

}

void ssd0303_init(DisplayState *ds, i2c_bus *bus, int address)

{

    ssd0303_state *s;

    s = (ssd0303_state *)i2c_slave_init(bus, address, sizeof(ssd0303_state));

    s->i2c.event = ssd0303_event;

    s->i2c.recv = ssd0303_recv;

    s->i2c.send = ssd0303_send;

    s->ds = gui_get_graphic_console(NULL,

                                    ssd0303_update_display,

                                    ssd0303_invalidate_display,

                                    NULL, s);

    gui_resize_vt(s->ds, 96 * MAGNIFY, 16 * MAGNIFY);

    register_savevm("ssd0303_oled", -1, 1, ssd0303_save, ssd0303_load, s);

}