mt9v011.c

Go to the documentation of this file.

/*
 * mt9v011 -Micron 1/4-Inch VGA Digital Image Sensor
 *
 * Copyright (c) 2009 Mauro Carvalho Chehab ([email protected])
 * This code is placed under the terms of the GNU General Public License v2
 */

#include <linux/i2c.h>
#include <linux/slab.h>
#include <linux/videodev2.h>
#include <linux/delay.h>
#include <linux/module.h>
#include <asm/div64.h>
#include <media/v4l2-device.h>
#include <media/v4l2-chip-ident.h>
#include <media/mt9v011.h>

MODULE_DESCRIPTION("Micron mt9v011 sensor driver");
MODULE_AUTHOR("Mauro Carvalho Chehab <[email protected]>");
MODULE_LICENSE("GPL");

static int debug;
module_param(debug, int, 0);
MODULE_PARM_DESC(debug, "Debug level (0-2)");

#define R00_MT9V011_CHIP_VERSION    0x00
#define R01_MT9V011_ROWSTART        0x01
#define R02_MT9V011_COLSTART        0x02
#define R03_MT9V011_HEIGHT      0x03
#define R04_MT9V011_WIDTH       0x04
#define R05_MT9V011_HBLANK      0x05
#define R06_MT9V011_VBLANK      0x06
#define R07_MT9V011_OUT_CTRL        0x07
#define R09_MT9V011_SHUTTER_WIDTH   0x09
#define R0A_MT9V011_CLK_SPEED       0x0a
#define R0B_MT9V011_RESTART     0x0b
#define R0C_MT9V011_SHUTTER_DELAY   0x0c
#define R0D_MT9V011_RESET       0x0d
#define R1E_MT9V011_DIGITAL_ZOOM    0x1e
#define R20_MT9V011_READ_MODE       0x20
#define R2B_MT9V011_GREEN_1_GAIN    0x2b
#define R2C_MT9V011_BLUE_GAIN       0x2c
#define R2D_MT9V011_RED_GAIN        0x2d
#define R2E_MT9V011_GREEN_2_GAIN    0x2e
#define R35_MT9V011_GLOBAL_GAIN     0x35
#define RF1_MT9V011_CHIP_ENABLE     0xf1

#define MT9V011_VERSION         0x8232
#define MT9V011_REV_B_VERSION       0x8243

/* supported controls */
static struct v4l2_queryctrl mt9v011_qctrl[] = {
    {
        .id = V4L2_CID_GAIN,
        .type = V4L2_CTRL_TYPE_INTEGER,
        .name = "Gain",
        .minimum = 0,
        .maximum = (1 << 12) - 1 - 0x0020,
        .step = 1,
        .default_value = 0x0020,
        .flags = 0,
    }, {
        .id = V4L2_CID_EXPOSURE,
        .type = V4L2_CTRL_TYPE_INTEGER,
        .name = "Exposure",
        .minimum = 0,
        .maximum = 2047,
        .step = 1,
        .default_value = 0x01fc,
        .flags = 0,
    }, {
        .id = V4L2_CID_RED_BALANCE,
        .type = V4L2_CTRL_TYPE_INTEGER,
        .name = "Red Balance",
        .minimum = -1 << 9,
        .maximum = (1 << 9) - 1,
        .step = 1,
        .default_value = 0,
        .flags = 0,
    }, {
        .id = V4L2_CID_BLUE_BALANCE,
        .type = V4L2_CTRL_TYPE_INTEGER,
        .name = "Blue Balance",
        .minimum = -1 << 9,
        .maximum = (1 << 9) - 1,
        .step = 1,
        .default_value = 0,
        .flags = 0,
    }, {
        .id      = V4L2_CID_HFLIP,
        .type    = V4L2_CTRL_TYPE_BOOLEAN,
        .name    = "Mirror",
        .minimum = 0,
        .maximum = 1,
        .step    = 1,
        .default_value = 0,
        .flags = 0,
    }, {
        .id      = V4L2_CID_VFLIP,
        .type    = V4L2_CTRL_TYPE_BOOLEAN,
        .name    = "Vflip",
        .minimum = 0,
        .maximum = 1,
        .step    = 1,
        .default_value = 0,
        .flags = 0,
    }, {
    }
};

struct mt9v011 {
    struct v4l2_subdev sd;
    unsigned width, height;
    unsigned xtal;
    unsigned hflip:1;
    unsigned vflip:1;

    u16 global_gain, exposure;
    s16 red_bal, blue_bal;
};

static inline struct mt9v011 *to_mt9v011(struct v4l2_subdev *sd)
{
    return container_of(sd, struct mt9v011, sd);
}

static int mt9v011_read(struct v4l2_subdev *sd, unsigned char addr)
{
    struct i2c_client *c = v4l2_get_subdevdata(sd);
    __be16 buffer;
    int rc, val;

    rc = i2c_master_send(c, &addr, 1);
    if (rc != 1)
        v4l2_dbg(0, debug, sd,
             "i2c i/o error: rc == %d (should be 1)\n", rc);

    msleep(10);

    rc = i2c_master_recv(c, (char *)&buffer, 2);
    if (rc != 2)
        v4l2_dbg(0, debug, sd,
             "i2c i/o error: rc == %d (should be 2)\n", rc);

    val = be16_to_cpu(buffer);

    v4l2_dbg(2, debug, sd, "mt9v011: read 0x%02x = 0x%04x\n", addr, val);

    return val;
}

static void mt9v011_write(struct v4l2_subdev *sd, unsigned char addr,
                 u16 value)
{
    struct i2c_client *c = v4l2_get_subdevdata(sd);
    unsigned char buffer[3];
    int rc;

    buffer[0] = addr;
    buffer[1] = value >> 8;
    buffer[2] = value & 0xff;

    v4l2_dbg(2, debug, sd,
         "mt9v011: writing 0x%02x 0x%04x\n", buffer[0], value);
    rc = i2c_master_send(c, buffer, 3);
    if (rc != 3)
        v4l2_dbg(0, debug, sd,
             "i2c i/o error: rc == %d (should be 3)\n", rc);
}


struct i2c_reg_value {
    unsigned char reg;
    u16           value;
};

/*
 * Values used at the original driver
 * Some values are marked as Reserved at the datasheet
 */
static const struct i2c_reg_value mt9v011_init_default[] = {
        { R0D_MT9V011_RESET, 0x0001 },
        { R0D_MT9V011_RESET, 0x0000 },

        { R0C_MT9V011_SHUTTER_DELAY, 0x0000 },
        { R09_MT9V011_SHUTTER_WIDTH, 0x1fc },

        { R0A_MT9V011_CLK_SPEED, 0x0000 },
        { R1E_MT9V011_DIGITAL_ZOOM,  0x0000 },

        { R07_MT9V011_OUT_CTRL, 0x0002 },   /* chip enable */
};


static u16 calc_mt9v011_gain(s16 lineargain)
{

    u16 digitalgain = 0;
    u16 analogmult = 0;
    u16 analoginit = 0;

    if (lineargain < 0)
        lineargain = 0;

    /* recommended minimum */
    lineargain += 0x0020;

    if (lineargain > 2047)
        lineargain = 2047;

    if (lineargain > 1023) {
        digitalgain = 3;
        analogmult = 3;
        analoginit = lineargain / 16;
    } else if (lineargain > 511) {
        digitalgain = 1;
        analogmult = 3;
        analoginit = lineargain / 8;
    } else if (lineargain > 255) {
        analogmult = 3;
        analoginit = lineargain / 4;
    } else if (lineargain > 127) {
        analogmult = 1;
        analoginit = lineargain / 2;
    } else
        analoginit = lineargain;

    return analoginit + (analogmult << 7) + (digitalgain << 9);

}

static void set_balance(struct v4l2_subdev *sd)
{
    struct mt9v011 *core = to_mt9v011(sd);
    u16 green_gain, blue_gain, red_gain;
    u16 exposure;
    s16 bal;

    exposure = core->exposure;

    green_gain = calc_mt9v011_gain(core->global_gain);

    bal = core->global_gain;
    bal += (core->blue_bal * core->global_gain / (1 << 7));
    blue_gain = calc_mt9v011_gain(bal);

    bal = core->global_gain;
    bal += (core->red_bal * core->global_gain / (1 << 7));
    red_gain = calc_mt9v011_gain(bal);

    mt9v011_write(sd, R2B_MT9V011_GREEN_1_GAIN, green_gain);
    mt9v011_write(sd, R2E_MT9V011_GREEN_2_GAIN, green_gain);
    mt9v011_write(sd, R2C_MT9V011_BLUE_GAIN, blue_gain);
    mt9v011_write(sd, R2D_MT9V011_RED_GAIN, red_gain);
    mt9v011_write(sd, R09_MT9V011_SHUTTER_WIDTH, exposure);
}

static void calc_fps(struct v4l2_subdev *sd, u32 *numerator, u32 *denominator)
{
    struct mt9v011 *core = to_mt9v011(sd);
    unsigned height, width, hblank, vblank, speed;
    unsigned row_time, t_time;
    u64 frames_per_ms;
    unsigned tmp;

    height = mt9v011_read(sd, R03_MT9V011_HEIGHT);
    width = mt9v011_read(sd, R04_MT9V011_WIDTH);
    hblank = mt9v011_read(sd, R05_MT9V011_HBLANK);
    vblank = mt9v011_read(sd, R06_MT9V011_VBLANK);
    speed = mt9v011_read(sd, R0A_MT9V011_CLK_SPEED);

    row_time = (width + 113 + hblank) * (speed + 2);
    t_time = row_time * (height + vblank + 1);

    frames_per_ms = core->xtal * 1000l;
    do_div(frames_per_ms, t_time);
    tmp = frames_per_ms;

    v4l2_dbg(1, debug, sd, "Programmed to %u.%03u fps (%d pixel clcks)\n",
        tmp / 1000, tmp % 1000, t_time);

    if (numerator && denominator) {
        *numerator = 1000;
        *denominator = (u32)frames_per_ms;
    }
}

static u16 calc_speed(struct v4l2_subdev *sd, u32 numerator, u32 denominator)
{
    struct mt9v011 *core = to_mt9v011(sd);
    unsigned height, width, hblank, vblank;
    unsigned row_time, line_time;
    u64 t_time, speed;

    /* Avoid bogus calculus */
    if (!numerator || !denominator)
        return 0;

    height = mt9v011_read(sd, R03_MT9V011_HEIGHT);
    width = mt9v011_read(sd, R04_MT9V011_WIDTH);
    hblank = mt9v011_read(sd, R05_MT9V011_HBLANK);
    vblank = mt9v011_read(sd, R06_MT9V011_VBLANK);

    row_time = width + 113 + hblank;
    line_time = height + vblank + 1;

    t_time = core->xtal * ((u64)numerator);
    /* round to the closest value */
    t_time += denominator / 2;
    do_div(t_time, denominator);

    speed = t_time;
    do_div(speed, row_time * line_time);

    /* Avoid having a negative value for speed */
    if (speed < 2)
        speed = 0;
    else
        speed -= 2;

    /* Avoid speed overflow */
    if (speed > 15)
        return 15;

    return (u16)speed;
}

static void set_res(struct v4l2_subdev *sd)
{
    struct mt9v011 *core = to_mt9v011(sd);
    unsigned vstart, hstart;

    /*
     * The mt9v011 doesn't have scaling. So, in order to select the desired
     * resolution, we're cropping at the middle of the sensor.
     * hblank and vblank should be adjusted, in order to warrant that
     * we'll preserve the line timings for 30 fps, no matter what resolution
     * is selected.
     * NOTE: datasheet says that width (and height) should be filled with
     * width-1. However, this doesn't work, since one pixel per line will
     * be missing.
     */

    hstart = 20 + (640 - core->width) / 2;
    mt9v011_write(sd, R02_MT9V011_COLSTART, hstart);
    mt9v011_write(sd, R04_MT9V011_WIDTH, core->width);
    mt9v011_write(sd, R05_MT9V011_HBLANK, 771 - core->width);

    vstart = 8 + (480 - core->height) / 2;
    mt9v011_write(sd, R01_MT9V011_ROWSTART, vstart);
    mt9v011_write(sd, R03_MT9V011_HEIGHT, core->height);
    mt9v011_write(sd, R06_MT9V011_VBLANK, 508 - core->height);

    calc_fps(sd, NULL, NULL);
};

static void set_read_mode(struct v4l2_subdev *sd)
{
    struct mt9v011 *core = to_mt9v011(sd);
    unsigned mode = 0x1000;

    if (core->hflip)
        mode |= 0x4000;

    if (core->vflip)
        mode |= 0x8000;

    mt9v011_write(sd, R20_MT9V011_READ_MODE, mode);
}

static int mt9v011_reset(struct v4l2_subdev *sd, u32 val)
{
    int i;

    for (i = 0; i < ARRAY_SIZE(mt9v011_init_default); i++)
        mt9v011_write(sd, mt9v011_init_default[i].reg,
                   mt9v011_init_default[i].value);

    set_balance(sd);
    set_res(sd);
    set_read_mode(sd);

    return 0;
};

static int mt9v011_g_ctrl(struct v4l2_subdev *sd, struct v4l2_control *ctrl)
{
    struct mt9v011 *core = to_mt9v011(sd);

    v4l2_dbg(1, debug, sd, "g_ctrl called\n");

    switch (ctrl->id) {
    case V4L2_CID_GAIN:
        ctrl->value = core->global_gain;
        return 0;
    case V4L2_CID_EXPOSURE:
        ctrl->value = core->exposure;
        return 0;
    case V4L2_CID_RED_BALANCE:
        ctrl->value = core->red_bal;
        return 0;
    case V4L2_CID_BLUE_BALANCE:
        ctrl->value = core->blue_bal;
        return 0;
    case V4L2_CID_HFLIP:
        ctrl->value = core->hflip ? 1 : 0;
        return 0;
    case V4L2_CID_VFLIP:
        ctrl->value = core->vflip ? 1 : 0;
        return 0;
    }
    return -EINVAL;
}

static int mt9v011_queryctrl(struct v4l2_subdev *sd, struct v4l2_queryctrl *qc)
{
    int i;

    v4l2_dbg(1, debug, sd, "queryctrl called\n");

    for (i = 0; i < ARRAY_SIZE(mt9v011_qctrl); i++)
        if (qc->id && qc->id == mt9v011_qctrl[i].id) {
            memcpy(qc, &(mt9v011_qctrl[i]),
                   sizeof(*qc));
            return 0;
        }

    return -EINVAL;
}


static int mt9v011_s_ctrl(struct v4l2_subdev *sd, struct v4l2_control *ctrl)
{
    struct mt9v011 *core = to_mt9v011(sd);
    u8 i, n;
    n = ARRAY_SIZE(mt9v011_qctrl);

    for (i = 0; i < n; i++) {
        if (ctrl->id != mt9v011_qctrl[i].id)
            continue;
        if (ctrl->value < mt9v011_qctrl[i].minimum ||
            ctrl->value > mt9v011_qctrl[i].maximum)
            return -ERANGE;
        v4l2_dbg(1, debug, sd, "s_ctrl: id=%d, value=%d\n",
                    ctrl->id, ctrl->value);
        break;
    }

    switch (ctrl->id) {
    case V4L2_CID_GAIN:
        core->global_gain = ctrl->value;
        break;
    case V4L2_CID_EXPOSURE:
        core->exposure = ctrl->value;
        break;
    case V4L2_CID_RED_BALANCE:
        core->red_bal = ctrl->value;
        break;
    case V4L2_CID_BLUE_BALANCE:
        core->blue_bal = ctrl->value;
        break;
    case V4L2_CID_HFLIP:
        core->hflip = ctrl->value;
        set_read_mode(sd);
        return 0;
    case V4L2_CID_VFLIP:
        core->vflip = ctrl->value;
        set_read_mode(sd);
        return 0;
    default:
        return -EINVAL;
    }

    set_balance(sd);

    return 0;
}

static int mt9v011_enum_mbus_fmt(struct v4l2_subdev *sd, unsigned index,
                    enum v4l2_mbus_pixelcode *code)
{
    if (index > 0)
        return -EINVAL;

    *code = V4L2_MBUS_FMT_SGRBG8_1X8;
    return 0;
}

static int mt9v011_try_mbus_fmt(struct v4l2_subdev *sd, struct v4l2_mbus_framefmt *fmt)
{
    if (fmt->code != V4L2_MBUS_FMT_SGRBG8_1X8)
        return -EINVAL;

    v4l_bound_align_image(&fmt->width, 48, 639, 1,
                  &fmt->height, 32, 480, 1, 0);
    fmt->field = V4L2_FIELD_NONE;
    fmt->colorspace = V4L2_COLORSPACE_SRGB;

    return 0;
}

static int mt9v011_g_parm(struct v4l2_subdev *sd, struct v4l2_streamparm *parms)
{
    struct v4l2_captureparm *cp = &parms->parm.capture;

    if (parms->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
        return -EINVAL;

    memset(cp, 0, sizeof(struct v4l2_captureparm));
    cp->capability = V4L2_CAP_TIMEPERFRAME;
    calc_fps(sd,
         &cp->timeperframe.numerator,
         &cp->timeperframe.denominator);

    return 0;
}

static int mt9v011_s_parm(struct v4l2_subdev *sd, struct v4l2_streamparm *parms)
{
    struct v4l2_captureparm *cp = &parms->parm.capture;
    struct v4l2_fract *tpf = &cp->timeperframe;
    u16 speed;

    if (parms->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
        return -EINVAL;
    if (cp->extendedmode != 0)
        return -EINVAL;

    speed = calc_speed(sd, tpf->numerator, tpf->denominator);

    mt9v011_write(sd, R0A_MT9V011_CLK_SPEED, speed);
    v4l2_dbg(1, debug, sd, "Setting speed to %d\n", speed);

    /* Recalculate and update fps info */
    calc_fps(sd, &tpf->numerator, &tpf->denominator);

    return 0;
}

static int mt9v011_s_mbus_fmt(struct v4l2_subdev *sd, struct v4l2_mbus_framefmt *fmt)
{
    struct mt9v011 *core = to_mt9v011(sd);
    int rc;

    rc = mt9v011_try_mbus_fmt(sd, fmt);
    if (rc < 0)
        return -EINVAL;

    core->width = fmt->width;
    core->height = fmt->height;

    set_res(sd);

    return 0;
}

#ifdef CONFIG_VIDEO_ADV_DEBUG
static int mt9v011_g_register(struct v4l2_subdev *sd,
                  struct v4l2_dbg_register *reg)
{
    struct i2c_client *client = v4l2_get_subdevdata(sd);

    if (!v4l2_chip_match_i2c_client(client, &reg->match))
        return -EINVAL;
    if (!capable(CAP_SYS_ADMIN))
        return -EPERM;

    reg->val = mt9v011_read(sd, reg->reg & 0xff);
    reg->size = 2;

    return 0;
}

static int mt9v011_s_register(struct v4l2_subdev *sd,
                  struct v4l2_dbg_register *reg)
{
    struct i2c_client *client = v4l2_get_subdevdata(sd);

    if (!v4l2_chip_match_i2c_client(client, &reg->match))
        return -EINVAL;
    if (!capable(CAP_SYS_ADMIN))
        return -EPERM;

    mt9v011_write(sd, reg->reg & 0xff, reg->val & 0xffff);

    return 0;
}
#endif

static int mt9v011_g_chip_ident(struct v4l2_subdev *sd,
                struct v4l2_dbg_chip_ident *chip)
{
    u16 version;
    struct i2c_client *client = v4l2_get_subdevdata(sd);

    version = mt9v011_read(sd, R00_MT9V011_CHIP_VERSION);

    return v4l2_chip_ident_i2c_client(client, chip, V4L2_IDENT_MT9V011,
                      version);
}

static const struct v4l2_subdev_core_ops mt9v011_core_ops = {
    .queryctrl = mt9v011_queryctrl,
    .g_ctrl = mt9v011_g_ctrl,
    .s_ctrl = mt9v011_s_ctrl,
    .reset = mt9v011_reset,
    .g_chip_ident = mt9v011_g_chip_ident,
#ifdef CONFIG_VIDEO_ADV_DEBUG
    .g_register = mt9v011_g_register,
    .s_register = mt9v011_s_register,
#endif
};

static const struct v4l2_subdev_video_ops mt9v011_video_ops = {
    .enum_mbus_fmt = mt9v011_enum_mbus_fmt,
    .try_mbus_fmt = mt9v011_try_mbus_fmt,
    .s_mbus_fmt = mt9v011_s_mbus_fmt,
    .g_parm = mt9v011_g_parm,
    .s_parm = mt9v011_s_parm,
};

static const struct v4l2_subdev_ops mt9v011_ops = {
    .core  = &mt9v011_core_ops,
    .video = &mt9v011_video_ops,
};


/****************************************************************************
            I2C Client & Driver
 ****************************************************************************/

static int mt9v011_probe(struct i2c_client *c,
             const struct i2c_device_id *id)
{
    u16 version;
    struct mt9v011 *core;
    struct v4l2_subdev *sd;

    /* Check if the adapter supports the needed features */
    if (!i2c_check_functionality(c->adapter,
         I2C_FUNC_SMBUS_READ_BYTE | I2C_FUNC_SMBUS_WRITE_BYTE_DATA))
        return -EIO;

    core = kzalloc(sizeof(struct mt9v011), GFP_KERNEL);
    if (!core)
        return -ENOMEM;

    sd = &core->sd;
    v4l2_i2c_subdev_init(sd, c, &mt9v011_ops);

    /* Check if the sensor is really a MT9V011 */
    version = mt9v011_read(sd, R00_MT9V011_CHIP_VERSION);
    if ((version != MT9V011_VERSION) &&
        (version != MT9V011_REV_B_VERSION)) {
        v4l2_info(sd, "*** unknown micron chip detected (0x%04x).\n",
              version);
        kfree(core);
        return -EINVAL;
    }

    core->global_gain = 0x0024;
    core->exposure = 0x01fc;
    core->width  = 640;
    core->height = 480;
    core->xtal = 27000000;  /* Hz */

    if (c->dev.platform_data) {
        struct mt9v011_platform_data *pdata = c->dev.platform_data;

        core->xtal = pdata->xtal;
        v4l2_dbg(1, debug, sd, "xtal set to %d.%03d MHz\n",
            core->xtal / 1000000, (core->xtal / 1000) % 1000);
    }

    v4l_info(c, "chip found @ 0x%02x (%s - chip version 0x%04x)\n",
         c->addr << 1, c->adapter->name, version);

    return 0;
}

static int mt9v011_remove(struct i2c_client *c)
{
    struct v4l2_subdev *sd = i2c_get_clientdata(c);

    v4l2_dbg(1, debug, sd,
        "mt9v011.c: removing mt9v011 adapter on address 0x%x\n",
        c->addr << 1);

    v4l2_device_unregister_subdev(sd);
    kfree(to_mt9v011(sd));
    return 0;
}

/* ----------------------------------------------------------------------- */

static const struct i2c_device_id mt9v011_id[] = {
    { "mt9v011", 0 },
    { }
};
MODULE_DEVICE_TABLE(i2c, mt9v011_id);

static struct i2c_driver mt9v011_driver = {
    .driver = {
        .owner  = THIS_MODULE,
        .name   = "mt9v011",
    },
    .probe      = mt9v011_probe,
    .remove     = mt9v011_remove,
    .id_table   = mt9v011_id,
};

module_i2c_driver(mt9v011_driver);