drivers/media/video/mt9t031.c

   1 /*
   2  * Driver for MT9T031 CMOS Image Sensor from Micron
   3  *
   4  * Copyright (C) 2008, Guennadi Liakhovetski, DENX Software Engineering <lg@denx.de>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  */
  10
  11 #include <linux/videodev2.h>
  12 #include <linux/slab.h>
  13 #include <linux/i2c.h>
  14 #include <linux/log2.h>
  15
  16 #include <media/v4l2-subdev.h>
  17 #include <media/v4l2-chip-ident.h>
  18 #include <media/soc_camera.h>
  19
  20 /* mt9t031 i2c address 0x5d
  21  * The platform has to define i2c_board_info and link to it from
  22  * struct soc_camera_link */
  23
  24 /* mt9t031 selected register addresses */
  25 #define MT9T031_CHIP_VERSION            0x00
  26 #define MT9T031_ROW_START               0x01
  27 #define MT9T031_COLUMN_START            0x02
  28 #define MT9T031_WINDOW_HEIGHT           0x03
  29 #define MT9T031_WINDOW_WIDTH            0x04
  30 #define MT9T031_HORIZONTAL_BLANKING     0x05
  31 #define MT9T031_VERTICAL_BLANKING       0x06
  32 #define MT9T031_OUTPUT_CONTROL          0x07
  33 #define MT9T031_SHUTTER_WIDTH_UPPER     0x08
  34 #define MT9T031_SHUTTER_WIDTH           0x09
  35 #define MT9T031_PIXEL_CLOCK_CONTROL     0x0a
  36 #define MT9T031_FRAME_RESTART           0x0b
  37 #define MT9T031_SHUTTER_DELAY           0x0c
  38 #define MT9T031_RESET                   0x0d
  39 #define MT9T031_READ_MODE_1             0x1e
  40 #define MT9T031_READ_MODE_2             0x20
  41 #define MT9T031_READ_MODE_3             0x21
  42 #define MT9T031_ROW_ADDRESS_MODE        0x22
  43 #define MT9T031_COLUMN_ADDRESS_MODE     0x23
  44 #define MT9T031_GLOBAL_GAIN             0x35
  45 #define MT9T031_CHIP_ENABLE             0xF8
  46
  47 #define MT9T031_MAX_HEIGHT              1536
  48 #define MT9T031_MAX_WIDTH               2048
  49 #define MT9T031_MIN_HEIGHT              2
  50 #define MT9T031_MIN_WIDTH               18
  51 #define MT9T031_HORIZONTAL_BLANK        142
  52 #define MT9T031_VERTICAL_BLANK          25
  53 #define MT9T031_COLUMN_SKIP             32
  54 #define MT9T031_ROW_SKIP                20
  55
  56 #define MT9T031_BUS_PARAM       (SOCAM_PCLK_SAMPLE_RISING |     \
  57         SOCAM_PCLK_SAMPLE_FALLING | SOCAM_HSYNC_ACTIVE_HIGH |   \
  58         SOCAM_VSYNC_ACTIVE_HIGH | SOCAM_DATA_ACTIVE_HIGH |      \
  59         SOCAM_MASTER | SOCAM_DATAWIDTH_10)
  60
  61 static const struct soc_camera_data_format mt9t031_colour_formats[] = {
  62         {
  63                 .name           = "Bayer (sRGB) 10 bit",
  64                 .depth          = 10,
  65                 .fourcc         = V4L2_PIX_FMT_SGRBG10,
  66                 .colorspace     = V4L2_COLORSPACE_SRGB,
  67         }
  68 };
  69
  70 struct mt9t031 {
  71         struct v4l2_subdev subdev;
  72         struct v4l2_rect rect;  /* Sensor window */
  73         int model;      /* V4L2_IDENT_MT9T031* codes from v4l2-chip-ident.h */
  74         u16 xskip;
  75         u16 yskip;
  76         unsigned char autoexposure;
  77 };
  78
  79 static struct mt9t031 *to_mt9t031(const struct i2c_client *client)
  80 {
  81         return container_of(i2c_get_clientdata(client), struct mt9t031, subdev);
  82 }
  83
  84 static int reg_read(struct i2c_client *client, const u8 reg)
  85 {
  86         s32 data = i2c_smbus_read_word_data(client, reg);
  87         return data < 0 ? data : swab16(data);
  88 }
  89
  90 static int reg_write(struct i2c_client *client, const u8 reg,
  91                      const u16 data)
  92 {
  93         return i2c_smbus_write_word_data(client, reg, swab16(data));
  94 }
  95
  96 static int reg_set(struct i2c_client *client, const u8 reg,
  97                    const u16 data)
  98 {
  99         int ret;
 100
 101         ret = reg_read(client, reg);
 102         if (ret < 0)
 103                 return ret;
 104         return reg_write(client, reg, ret | data);
 105 }
 106
 107 static int reg_clear(struct i2c_client *client, const u8 reg,
 108                      const u16 data)
 109 {
 110         int ret;
 111
 112         ret = reg_read(client, reg);
 113         if (ret < 0)
 114                 return ret;
 115         return reg_write(client, reg, ret & ~data);
 116 }
 117
 118 static int set_shutter(struct i2c_client *client, const u32 data)
 119 {
 120         int ret;
 121
 122         ret = reg_write(client, MT9T031_SHUTTER_WIDTH_UPPER, data >> 16);
 123
 124         if (ret >= 0)
 125                 ret = reg_write(client, MT9T031_SHUTTER_WIDTH, data & 0xffff);
 126
 127         return ret;
 128 }
 129
 130 static int get_shutter(struct i2c_client *client, u32 *data)
 131 {
 132         int ret;
 133
 134         ret = reg_read(client, MT9T031_SHUTTER_WIDTH_UPPER);
 135         *data = ret << 16;
 136
 137         if (ret >= 0)
 138                 ret = reg_read(client, MT9T031_SHUTTER_WIDTH);
 139         *data |= ret & 0xffff;
 140
 141         return ret < 0 ? ret : 0;
 142 }
 143
 144 static int mt9t031_idle(struct i2c_client *client)
 145 {
 146         int ret;
 147
 148         /* Disable chip output, synchronous option update */
 149         ret = reg_write(client, MT9T031_RESET, 1);
 150         if (ret >= 0)
 151                 ret = reg_write(client, MT9T031_RESET, 0);
 152         if (ret >= 0)
 153                 ret = reg_clear(client, MT9T031_OUTPUT_CONTROL, 2);
 154
 155         return ret >= 0 ? 0 : -EIO;
 156 }
 157
 158 static int mt9t031_disable(struct i2c_client *client)
 159 {
 160         /* Disable the chip */
 161         reg_clear(client, MT9T031_OUTPUT_CONTROL, 2);
 162
 163         return 0;
 164 }
 165
 166 static int mt9t031_init(struct soc_camera_device *icd)
 167 {
 168         struct i2c_client *client = to_i2c_client(to_soc_camera_control(icd));
 169
 170         return mt9t031_idle(client);
 171 }
 172
 173 static int mt9t031_release(struct soc_camera_device *icd)
 174 {
 175         struct i2c_client *client = to_i2c_client(to_soc_camera_control(icd));
 176
 177         return mt9t031_disable(client);
 178 }
 179
 180 static int mt9t031_s_stream(struct v4l2_subdev *sd, int enable)
 181 {
 182         struct i2c_client *client = sd->priv;
 183         int ret;
 184
 185         if (enable)
 186                 /* Switch to master "normal" mode */
 187                 ret = reg_set(client, MT9T031_OUTPUT_CONTROL, 2);
 188         else
 189                 /* Stop sensor readout */
 190                 ret = reg_clear(client, MT9T031_OUTPUT_CONTROL, 2);
 191
 192         if (ret < 0)
 193                 return -EIO;
 194
 195         return 0;
 196 }
 197
 198 static int mt9t031_set_bus_param(struct soc_camera_device *icd,
 199                                  unsigned long flags)
 200 {
 201         struct i2c_client *client = to_i2c_client(to_soc_camera_control(icd));
 202
 203         /* The caller should have queried our parameters, check anyway */
 204         if (flags & ~MT9T031_BUS_PARAM)
 205                 return -EINVAL;
 206
 207         if (flags & SOCAM_PCLK_SAMPLE_FALLING)
 208                 reg_clear(client, MT9T031_PIXEL_CLOCK_CONTROL, 0x8000);
 209         else
 210                 reg_set(client, MT9T031_PIXEL_CLOCK_CONTROL, 0x8000);
 211
 212         return 0;
 213 }
 214
 215 static unsigned long mt9t031_query_bus_param(struct soc_camera_device *icd)
 216 {
 217         struct soc_camera_link *icl = to_soc_camera_link(icd);
 218
 219         return soc_camera_apply_sensor_flags(icl, MT9T031_BUS_PARAM);
 220 }
 221
 222 /* target must be _even_ */
 223 static u16 mt9t031_skip(s32 *source, s32 target, s32 max)
 224 {
 225         unsigned int skip;
 226
 227         if (*source < target + target / 2) {
 228                 *source = target;
 229                 return 1;
 230         }
 231
 232         skip = min(max, *source + target / 2) / target;
 233         if (skip > 8)
 234                 skip = 8;
 235         *source = target * skip;
 236
 237         return skip;
 238 }
 239
 240 /* rect is the sensor rectangle, the caller guarantees parameter validity */
 241 static int mt9t031_set_params(struct soc_camera_device *icd,
 242                               struct v4l2_rect *rect, u16 xskip, u16 yskip)
 243 {
 244         struct i2c_client *client = to_i2c_client(to_soc_camera_control(icd));
 245         struct mt9t031 *mt9t031 = to_mt9t031(client);
 246         int ret;
 247         u16 xbin, ybin;
 248         const u16 hblank = MT9T031_HORIZONTAL_BLANK,
 249                 vblank = MT9T031_VERTICAL_BLANK;
 250
 251         xbin = min(xskip, (u16)3);
 252         ybin = min(yskip, (u16)3);
 253
 254         /*
 255          * Could just do roundup(rect->left, [xy]bin * 2); but this is cheaper.
 256          * There is always a valid suitably aligned value. The worst case is
 257          * xbin = 3, width = 2048. Then we will start at 36, the last read out
 258          * pixel will be 2083, which is < 2085 - first black pixel.
 259          *
 260          * MT9T031 datasheet imposes window left border alignment, depending on
 261          * the selected xskip. Failing to conform to this requirement produces
 262          * dark horizontal stripes in the image. However, even obeying to this
 263          * requirement doesn't eliminate the stripes in all configurations. They
 264          * appear "locally reproducibly," but can differ between tests under
 265          * different lighting conditions.
 266          */
 267         switch (xbin) {
 268         case 1:
 269                 rect->left &= ~1;
 270                 break;
 271         case 2:
 272                 rect->left &= ~3;
 273                 break;
 274         case 3:
 275                 rect->left = rect->left > roundup(MT9T031_COLUMN_SKIP, 6) ?
 276                         (rect->left / 6) * 6 : roundup(MT9T031_COLUMN_SKIP, 6);
 277         }
 278
 279         rect->top &= ~1;
 280
 281         dev_dbg(&client->dev, "skip %u:%u, rect %ux%u@%u:%u\n",
 282                 xskip, yskip, rect->width, rect->height, rect->left, rect->top);
 283
 284         /* Disable register update, reconfigure atomically */
 285         ret = reg_set(client, MT9T031_OUTPUT_CONTROL, 1);
 286         if (ret < 0)
 287                 return ret;
 288
 289         /* Blanking and start values - default... */
 290         ret = reg_write(client, MT9T031_HORIZONTAL_BLANKING, hblank);
 291         if (ret >= 0)
 292                 ret = reg_write(client, MT9T031_VERTICAL_BLANKING, vblank);
 293
 294         if (yskip != mt9t031->yskip || xskip != mt9t031->xskip) {
 295                 /* Binning, skipping */
 296                 if (ret >= 0)
 297                         ret = reg_write(client, MT9T031_COLUMN_ADDRESS_MODE,
 298                                         ((xbin - 1) << 4) | (xskip - 1));
 299                 if (ret >= 0)
 300                         ret = reg_write(client, MT9T031_ROW_ADDRESS_MODE,
 301                                         ((ybin - 1) << 4) | (yskip - 1));
 302         }
 303         dev_dbg(&client->dev, "new physical left %u, top %u\n",
 304                 rect->left, rect->top);
 305
 306         /* The caller provides a supported format, as guaranteed by
 307          * icd->try_fmt_cap(), soc_camera_s_crop() and soc_camera_cropcap() */
 308         if (ret >= 0)
 309                 ret = reg_write(client, MT9T031_COLUMN_START, rect->left);
 310         if (ret >= 0)
 311                 ret = reg_write(client, MT9T031_ROW_START, rect->top);
 312         if (ret >= 0)
 313                 ret = reg_write(client, MT9T031_WINDOW_WIDTH, rect->width - 1);
 314         if (ret >= 0)
 315                 ret = reg_write(client, MT9T031_WINDOW_HEIGHT,
 316                                 rect->height + icd->y_skip_top - 1);
 317         if (ret >= 0 && mt9t031->autoexposure) {
 318                 ret = set_shutter(client,
 319                                   rect->height + icd->y_skip_top + vblank);
 320                 if (ret >= 0) {
 321                         const u32 shutter_max = MT9T031_MAX_HEIGHT + vblank;
 322                         const struct v4l2_queryctrl *qctrl =
 323                                 soc_camera_find_qctrl(icd->ops,
 324                                                       V4L2_CID_EXPOSURE);
 325                         icd->exposure = (shutter_max / 2 + (rect->height +
 326                                          icd->y_skip_top + vblank - 1) *
 327                                          (qctrl->maximum - qctrl->minimum)) /
 328                                 shutter_max + qctrl->minimum;
 329                 }
 330         }
 331
 332         /* Re-enable register update, commit all changes */
 333         if (ret >= 0)
 334                 ret = reg_clear(client, MT9T031_OUTPUT_CONTROL, 1);
 335
 336         if (ret >= 0) {
 337                 mt9t031->rect = *rect;
 338                 mt9t031->xskip = xskip;
 339                 mt9t031->yskip = yskip;
 340         }
 341
 342         return ret < 0 ? ret : 0;
 343 }
 344
 345 static int mt9t031_s_crop(struct v4l2_subdev *sd, struct v4l2_crop *a)
 346 {
 347         struct v4l2_rect rect = a->c;
 348         struct i2c_client *client = sd->priv;
 349         struct mt9t031 *mt9t031 = to_mt9t031(client);
 350         struct soc_camera_device *icd = client->dev.platform_data;
 351
 352         rect.width = ALIGN(rect.width, 2);
 353         rect.height = ALIGN(rect.height, 2);
 354
 355         soc_camera_limit_side(&rect.left, &rect.width,
 356                      MT9T031_COLUMN_SKIP, MT9T031_MIN_WIDTH, MT9T031_MAX_WIDTH);
 357
 358         soc_camera_limit_side(&rect.top, &rect.height,
 359                      MT9T031_ROW_SKIP, MT9T031_MIN_HEIGHT, MT9T031_MAX_HEIGHT);
 360
 361         return mt9t031_set_params(icd, &rect, mt9t031->xskip, mt9t031->yskip);
 362 }
 363
 364 static int mt9t031_g_crop(struct v4l2_subdev *sd, struct v4l2_crop *a)
 365 {
 366         struct i2c_client *client = sd->priv;
 367         struct mt9t031 *mt9t031 = to_mt9t031(client);
 368
 369         a->c    = mt9t031->rect;
 370         a->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
 371
 372         return 0;
 373 }
 374
 375 static int mt9t031_cropcap(struct v4l2_subdev *sd, struct v4l2_cropcap *a)
 376 {
 377         a->bounds.left                  = MT9T031_COLUMN_SKIP;
 378         a->bounds.top                   = MT9T031_ROW_SKIP;
 379         a->bounds.width                 = MT9T031_MAX_WIDTH;
 380         a->bounds.height                = MT9T031_MAX_HEIGHT;
 381         a->defrect                      = a->bounds;
 382         a->type                         = V4L2_BUF_TYPE_VIDEO_CAPTURE;
 383         a->pixelaspect.numerator        = 1;
 384         a->pixelaspect.denominator      = 1;
 385
 386         return 0;
 387 }
 388
 389 static int mt9t031_g_fmt(struct v4l2_subdev *sd, struct v4l2_format *f)
 390 {
 391         struct i2c_client *client = sd->priv;
 392         struct mt9t031 *mt9t031 = to_mt9t031(client);
 393         struct v4l2_pix_format *pix = &f->fmt.pix;
 394
 395         pix->width              = mt9t031->rect.width / mt9t031->xskip;
 396         pix->height             = mt9t031->rect.height / mt9t031->yskip;
 397         pix->pixelformat        = V4L2_PIX_FMT_SGRBG10;
 398         pix->field              = V4L2_FIELD_NONE;
 399         pix->colorspace         = V4L2_COLORSPACE_SRGB;
 400
 401         return 0;
 402 }
 403
 404 static int mt9t031_s_fmt(struct v4l2_subdev *sd, struct v4l2_format *f)
 405 {
 406         struct i2c_client *client = sd->priv;
 407         struct mt9t031 *mt9t031 = to_mt9t031(client);
 408         struct soc_camera_device *icd = client->dev.platform_data;
 409         struct v4l2_pix_format *pix = &f->fmt.pix;
 410         u16 xskip, yskip;
 411         struct v4l2_rect rect = mt9t031->rect;
 412
 413         /*
 414          * try_fmt has put width and height within limits.
 415          * S_FMT: use binning and skipping for scaling
 416          */
 417         xskip = mt9t031_skip(&rect.width, pix->width, MT9T031_MAX_WIDTH);
 418         yskip = mt9t031_skip(&rect.height, pix->height, MT9T031_MAX_HEIGHT);
 419
 420         /* mt9t031_set_params() doesn't change width and height */
 421         return mt9t031_set_params(icd, &rect, xskip, yskip);
 422 }
 423
 424 /*
 425  * If a user window larger than sensor window is requested, we'll increase the
 426  * sensor window.
 427  */
 428 static int mt9t031_try_fmt(struct v4l2_subdev *sd, struct v4l2_format *f)
 429 {
 430         struct v4l2_pix_format *pix = &f->fmt.pix;
 431
 432         v4l_bound_align_image(
 433                 &pix->width, MT9T031_MIN_WIDTH, MT9T031_MAX_WIDTH, 1,
 434                 &pix->height, MT9T031_MIN_HEIGHT, MT9T031_MAX_HEIGHT, 1, 0);
 435
 436         return 0;
 437 }
 438
 439 static int mt9t031_g_chip_ident(struct v4l2_subdev *sd,
 440                                 struct v4l2_dbg_chip_ident *id)
 441 {
 442         struct i2c_client *client = sd->priv;
 443         struct mt9t031 *mt9t031 = to_mt9t031(client);
 444
 445         if (id->match.type != V4L2_CHIP_MATCH_I2C_ADDR)
 446                 return -EINVAL;
 447
 448         if (id->match.addr != client->addr)
 449                 return -ENODEV;
 450
 451         id->ident       = mt9t031->model;
 452         id->revision    = 0;
 453
 454         return 0;
 455 }
 456
 457 #ifdef CONFIG_VIDEO_ADV_DEBUG
 458 static int mt9t031_g_register(struct v4l2_subdev *sd,
 459                               struct v4l2_dbg_register *reg)
 460 {
 461         struct i2c_client *client = sd->priv;
 462
 463         if (reg->match.type != V4L2_CHIP_MATCH_I2C_ADDR || reg->reg > 0xff)
 464                 return -EINVAL;
 465
 466         if (reg->match.addr != client->addr)
 467                 return -ENODEV;
 468
 469         reg->val = reg_read(client, reg->reg);
 470
 471         if (reg->val > 0xffff)
 472                 return -EIO;
 473
 474         return 0;
 475 }
 476
 477 static int mt9t031_s_register(struct v4l2_subdev *sd,
 478                               struct v4l2_dbg_register *reg)
 479 {
 480         struct i2c_client *client = sd->priv;
 481
 482         if (reg->match.type != V4L2_CHIP_MATCH_I2C_ADDR || reg->reg > 0xff)
 483                 return -EINVAL;
 484
 485         if (reg->match.addr != client->addr)
 486                 return -ENODEV;
 487
 488         if (reg_write(client, reg->reg, reg->val) < 0)
 489                 return -EIO;
 490
 491         return 0;
 492 }
 493 #endif
 494
 495 static const struct v4l2_queryctrl mt9t031_controls[] = {
 496         {
 497                 .id             = V4L2_CID_VFLIP,
 498                 .type           = V4L2_CTRL_TYPE_BOOLEAN,
 499                 .name           = "Flip Vertically",
 500                 .minimum        = 0,
 501                 .maximum        = 1,
 502                 .step           = 1,
 503                 .default_value  = 0,
 504         }, {
 505                 .id             = V4L2_CID_HFLIP,
 506                 .type           = V4L2_CTRL_TYPE_BOOLEAN,
 507                 .name           = "Flip Horizontally",
 508                 .minimum        = 0,
 509                 .maximum        = 1,
 510                 .step           = 1,
 511                 .default_value  = 0,
 512         }, {
 513                 .id             = V4L2_CID_GAIN,
 514                 .type           = V4L2_CTRL_TYPE_INTEGER,
 515                 .name           = "Gain",
 516                 .minimum        = 0,
 517                 .maximum        = 127,
 518                 .step           = 1,
 519                 .default_value  = 64,
 520                 .flags          = V4L2_CTRL_FLAG_SLIDER,
 521         }, {
 522                 .id             = V4L2_CID_EXPOSURE,
 523                 .type           = V4L2_CTRL_TYPE_INTEGER,
 524                 .name           = "Exposure",
 525                 .minimum        = 1,
 526                 .maximum        = 255,
 527                 .step           = 1,
 528                 .default_value  = 255,
 529                 .flags          = V4L2_CTRL_FLAG_SLIDER,
 530         }, {
 531                 .id             = V4L2_CID_EXPOSURE_AUTO,
 532                 .type           = V4L2_CTRL_TYPE_BOOLEAN,
 533                 .name           = "Automatic Exposure",
 534                 .minimum        = 0,
 535                 .maximum        = 1,
 536                 .step           = 1,
 537                 .default_value  = 1,
 538         }
 539 };
 540
 541 static struct soc_camera_ops mt9t031_ops = {
 542         .init                   = mt9t031_init,
 543         .release                = mt9t031_release,
 544         .set_bus_param          = mt9t031_set_bus_param,
 545         .query_bus_param        = mt9t031_query_bus_param,
 546         .controls               = mt9t031_controls,
 547         .num_controls           = ARRAY_SIZE(mt9t031_controls),
 548 };
 549
 550 static int mt9t031_g_ctrl(struct v4l2_subdev *sd, struct v4l2_control *ctrl)
 551 {
 552         struct i2c_client *client = sd->priv;
 553         struct mt9t031 *mt9t031 = to_mt9t031(client);
 554         int data;
 555
 556         switch (ctrl->id) {
 557         case V4L2_CID_VFLIP:
 558                 data = reg_read(client, MT9T031_READ_MODE_2);
 559                 if (data < 0)
 560                         return -EIO;
 561                 ctrl->value = !!(data & 0x8000);
 562                 break;
 563         case V4L2_CID_HFLIP:
 564                 data = reg_read(client, MT9T031_READ_MODE_2);
 565                 if (data < 0)
 566                         return -EIO;
 567                 ctrl->value = !!(data & 0x4000);
 568                 break;
 569         case V4L2_CID_EXPOSURE_AUTO:
 570                 ctrl->value = mt9t031->autoexposure;
 571                 break;
 572         }
 573         return 0;
 574 }
 575
 576 static int mt9t031_s_ctrl(struct v4l2_subdev *sd, struct v4l2_control *ctrl)
 577 {
 578         struct i2c_client *client = sd->priv;
 579         struct mt9t031 *mt9t031 = to_mt9t031(client);
 580         struct soc_camera_device *icd = client->dev.platform_data;
 581         const struct v4l2_queryctrl *qctrl;
 582         int data;
 583
 584         qctrl = soc_camera_find_qctrl(&mt9t031_ops, ctrl->id);
 585
 586         if (!qctrl)
 587                 return -EINVAL;
 588
 589         switch (ctrl->id) {
 590         case V4L2_CID_VFLIP:
 591                 if (ctrl->value)
 592                         data = reg_set(client, MT9T031_READ_MODE_2, 0x8000);
 593                 else
 594                         data = reg_clear(client, MT9T031_READ_MODE_2, 0x8000);
 595                 if (data < 0)
 596                         return -EIO;
 597                 break;
 598         case V4L2_CID_HFLIP:
 599                 if (ctrl->value)
 600                         data = reg_set(client, MT9T031_READ_MODE_2, 0x4000);
 601                 else
 602                         data = reg_clear(client, MT9T031_READ_MODE_2, 0x4000);
 603                 if (data < 0)
 604                         return -EIO;
 605                 break;
 606         case V4L2_CID_GAIN:
 607                 if (ctrl->value > qctrl->maximum || ctrl->value < qctrl->minimum)
 608                         return -EINVAL;
 609                 /* See Datasheet Table 7, Gain settings. */
 610                 if (ctrl->value <= qctrl->default_value) {
 611                         /* Pack it into 0..1 step 0.125, register values 0..8 */
 612                         unsigned long range = qctrl->default_value - qctrl->minimum;
 613                         data = ((ctrl->value - qctrl->minimum) * 8 + range / 2) / range;
 614
 615                         dev_dbg(&client->dev, "Setting gain %d\n", data);
 616                         data = reg_write(client, MT9T031_GLOBAL_GAIN, data);
 617                         if (data < 0)
 618                                 return -EIO;
 619                 } else {
 620                         /* Pack it into 1.125..128 variable step, register values 9..0x7860 */
 621                         /* We assume qctrl->maximum - qctrl->default_value - 1 > 0 */
 622                         unsigned long range = qctrl->maximum - qctrl->default_value - 1;
 623                         /* calculated gain: map 65..127 to 9..1024 step 0.125 */
 624                         unsigned long gain = ((ctrl->value - qctrl->default_value - 1) *
 625                                                1015 + range / 2) / range + 9;
 626
 627                         if (gain <= 32)         /* calculated gain 9..32 -> 9..32 */
 628                                 data = gain;
 629                         else if (gain <= 64)    /* calculated gain 33..64 -> 0x51..0x60 */
 630                                 data = ((gain - 32) * 16 + 16) / 32 + 80;
 631                         else
 632                                 /* calculated gain 65..1024 -> (1..120) << 8 + 0x60 */
 633                                 data = (((gain - 64 + 7) * 32) & 0xff00) | 0x60;
 634
 635                         dev_dbg(&client->dev, "Set gain from 0x%x to 0x%x\n",
 636                                 reg_read(client, MT9T031_GLOBAL_GAIN), data);
 637                         data = reg_write(client, MT9T031_GLOBAL_GAIN, data);
 638                         if (data < 0)
 639                                 return -EIO;
 640                 }
 641
 642                 /* Success */
 643                 icd->gain = ctrl->value;
 644                 break;
 645         case V4L2_CID_EXPOSURE:
 646                 /* mt9t031 has maximum == default */
 647                 if (ctrl->value > qctrl->maximum || ctrl->value < qctrl->minimum)
 648                         return -EINVAL;
 649                 else {
 650                         const unsigned long range = qctrl->maximum - qctrl->minimum;
 651                         const u32 shutter = ((ctrl->value - qctrl->minimum) * 1048 +
 652                                              range / 2) / range + 1;
 653                         u32 old;
 654
 655                         get_shutter(client, &old);
 656                         dev_dbg(&client->dev, "Set shutter from %u to %u\n",
 657                                 old, shutter);
 658                         if (set_shutter(client, shutter) < 0)
 659                                 return -EIO;
 660                         icd->exposure = ctrl->value;
 661                         mt9t031->autoexposure = 0;
 662                 }
 663                 break;
 664         case V4L2_CID_EXPOSURE_AUTO:
 665                 if (ctrl->value) {
 666                         const u16 vblank = MT9T031_VERTICAL_BLANK;
 667                         const u32 shutter_max = MT9T031_MAX_HEIGHT + vblank;
 668                         if (set_shutter(client, mt9t031->rect.height +
 669                                         icd->y_skip_top + vblank) < 0)
 670                                 return -EIO;
 671                         qctrl = soc_camera_find_qctrl(icd->ops, V4L2_CID_EXPOSURE);
 672                         icd->exposure = (shutter_max / 2 +
 673                                          (mt9t031->rect.height +
 674                                           icd->y_skip_top + vblank - 1) *
 675                                          (qctrl->maximum - qctrl->minimum)) /
 676                                 shutter_max + qctrl->minimum;
 677                         mt9t031->autoexposure = 1;
 678                 } else
 679                         mt9t031->autoexposure = 0;
 680                 break;
 681         }
 682         return 0;
 683 }
 684
 685 /* Interface active, can use i2c. If it fails, it can indeed mean, that
 686  * this wasn't our capture interface, so, we wait for the right one */
 687 static int mt9t031_video_probe(struct i2c_client *client)
 688 {
 689         struct soc_camera_device *icd = client->dev.platform_data;
 690         struct mt9t031 *mt9t031 = to_mt9t031(client);
 691         s32 data;
 692
 693         /* Enable the chip */
 694         data = reg_write(client, MT9T031_CHIP_ENABLE, 1);
 695         dev_dbg(&client->dev, "write: %d\n", data);
 696
 697         /* Read out the chip version register */
 698         data = reg_read(client, MT9T031_CHIP_VERSION);
 699
 700         switch (data) {
 701         case 0x1621:
 702                 mt9t031->model = V4L2_IDENT_MT9T031;
 703                 icd->formats = mt9t031_colour_formats;
 704                 icd->num_formats = ARRAY_SIZE(mt9t031_colour_formats);
 705                 break;
 706         default:
 707                 dev_err(&client->dev,
 708                         "No MT9T031 chip detected, register read %x\n", data);
 709                 return -ENODEV;
 710         }
 711
 712         dev_info(&client->dev, "Detected a MT9T031 chip ID %x\n", data);
 713
 714         return 0;
 715 }
 716
 717 static struct v4l2_subdev_core_ops mt9t031_subdev_core_ops = {
 718         .g_ctrl         = mt9t031_g_ctrl,
 719         .s_ctrl         = mt9t031_s_ctrl,
 720         .g_chip_ident   = mt9t031_g_chip_ident,
 721 #ifdef CONFIG_VIDEO_ADV_DEBUG
 722         .g_register     = mt9t031_g_register,
 723         .s_register     = mt9t031_s_register,
 724 #endif
 725 };
 726
 727 static struct v4l2_subdev_video_ops mt9t031_subdev_video_ops = {
 728         .s_stream       = mt9t031_s_stream,
 729         .s_fmt          = mt9t031_s_fmt,
 730         .g_fmt          = mt9t031_g_fmt,
 731         .try_fmt        = mt9t031_try_fmt,
 732         .s_crop         = mt9t031_s_crop,
 733         .g_crop         = mt9t031_g_crop,
 734         .cropcap        = mt9t031_cropcap,
 735 };
 736
 737 static struct v4l2_subdev_ops mt9t031_subdev_ops = {
 738         .core   = &mt9t031_subdev_core_ops,
 739         .video  = &mt9t031_subdev_video_ops,
 740 };
 741
 742 static int mt9t031_probe(struct i2c_client *client,
 743                          const struct i2c_device_id *did)
 744 {
 745         struct mt9t031 *mt9t031;
 746         struct soc_camera_device *icd = client->dev.platform_data;
 747         struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
 748         struct soc_camera_link *icl;
 749         int ret;
 750
 751         if (!icd) {
 752                 dev_err(&client->dev, "MT9T031: missing soc-camera data!\n");
 753                 return -EINVAL;
 754         }
 755
 756         icl = to_soc_camera_link(icd);
 757         if (!icl) {
 758                 dev_err(&client->dev, "MT9T031 driver needs platform data\n");
 759                 return -EINVAL;
 760         }
 761
 762         if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA)) {
 763                 dev_warn(&adapter->dev,
 764                          "I2C-Adapter doesn't support I2C_FUNC_SMBUS_WORD\n");
 765                 return -EIO;
 766         }
 767
 768         mt9t031 = kzalloc(sizeof(struct mt9t031), GFP_KERNEL);
 769         if (!mt9t031)
 770                 return -ENOMEM;
 771
 772         v4l2_i2c_subdev_init(&mt9t031->subdev, client, &mt9t031_subdev_ops);
 773
 774         /* Second stage probe - when a capture adapter is there */
 775         icd->ops                = &mt9t031_ops;
 776         icd->y_skip_top         = 0;
 777
 778         mt9t031->rect.left      = MT9T031_COLUMN_SKIP;
 779         mt9t031->rect.top       = MT9T031_ROW_SKIP;
 780         mt9t031->rect.width     = MT9T031_MAX_WIDTH;
 781         mt9t031->rect.height    = MT9T031_MAX_HEIGHT;
 782
 783         /* Simulated autoexposure. If enabled, we calculate shutter width
 784          * ourselves in the driver based on vertical blanking and frame width */
 785         mt9t031->autoexposure = 1;
 786
 787         mt9t031->xskip = 1;
 788         mt9t031->yskip = 1;
 789
 790         mt9t031_idle(client);
 791
 792         ret = mt9t031_video_probe(client);
 793
 794         mt9t031_disable(client);
 795
 796         if (ret) {
 797                 icd->ops = NULL;
 798                 i2c_set_clientdata(client, NULL);
 799                 kfree(mt9t031);
 800         }
 801
 802         return ret;
 803 }
 804
 805 static int mt9t031_remove(struct i2c_client *client)
 806 {
 807         struct mt9t031 *mt9t031 = to_mt9t031(client);
 808         struct soc_camera_device *icd = client->dev.platform_data;
 809
 810         icd->ops = NULL;
 811         i2c_set_clientdata(client, NULL);
 812         client->driver = NULL;
 813         kfree(mt9t031);
 814
 815         return 0;
 816 }
 817
 818 static const struct i2c_device_id mt9t031_id[] = {
 819         { "mt9t031", 0 },
 820         { }
 821 };
 822 MODULE_DEVICE_TABLE(i2c, mt9t031_id);
 823
 824 static struct i2c_driver mt9t031_i2c_driver = {
 825         .driver = {
 826                 .name = "mt9t031",
 827         },
 828         .probe          = mt9t031_probe,
 829         .remove         = mt9t031_remove,
 830         .id_table       = mt9t031_id,
 831 };
 832
 833 static int __init mt9t031_mod_init(void)
 834 {
 835         return i2c_add_driver(&mt9t031_i2c_driver);
 836 }
 837
 838 static void __exit mt9t031_mod_exit(void)
 839 {
 840         i2c_del_driver(&mt9t031_i2c_driver);
 841 }
 842
 843 module_init(mt9t031_mod_init);
 844 module_exit(mt9t031_mod_exit);
 845
 846 MODULE_DESCRIPTION("Micron MT9T031 Camera driver");
 847 MODULE_AUTHOR("Guennadi Liakhovetski <lg@denx.de>");
 848 MODULE_LICENSE("GPL v2");