SAFE public projects git trees. - safe/jmp/linux-2.6/blob - 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               2
  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         int model;      /* V4L2_IDENT_MT9T031* codes from v4l2-chip-ident.h */
  73         unsigned char autoexposure;
  74         u16 xskip;
  75         u16 yskip;
  76 };
  77
  78 static struct mt9t031 *to_mt9t031(const struct i2c_client *client)
  79 {
  80         return container_of(i2c_get_clientdata(client), struct mt9t031, subdev);
  81 }
  82
  83 static int reg_read(struct i2c_client *client, const u8 reg)
  84 {
  85         s32 data = i2c_smbus_read_word_data(client, reg);
  86         return data < 0 ? data : swab16(data);
  87 }
  88
  89 static int reg_write(struct i2c_client *client, const u8 reg,
  90                      const u16 data)
  91 {
  92         return i2c_smbus_write_word_data(client, reg, swab16(data));
  93 }
  94
  95 static int reg_set(struct i2c_client *client, const u8 reg,
  96                    const u16 data)
  97 {
  98         int ret;
  99
 100         ret = reg_read(client, reg);
 101         if (ret < 0)
 102                 return ret;
 103         return reg_write(client, reg, ret | data);
 104 }
 105
 106 static int reg_clear(struct i2c_client *client, const u8 reg,
 107                      const u16 data)
 108 {
 109         int ret;
 110
 111         ret = reg_read(client, reg);
 112         if (ret < 0)
 113                 return ret;
 114         return reg_write(client, reg, ret & ~data);
 115 }
 116
 117 static int set_shutter(struct i2c_client *client, const u32 data)
 118 {
 119         int ret;
 120
 121         ret = reg_write(client, MT9T031_SHUTTER_WIDTH_UPPER, data >> 16);
 122
 123         if (ret >= 0)
 124                 ret = reg_write(client, MT9T031_SHUTTER_WIDTH, data & 0xffff);
 125
 126         return ret;
 127 }
 128
 129 static int get_shutter(struct i2c_client *client, u32 *data)
 130 {
 131         int ret;
 132
 133         ret = reg_read(client, MT9T031_SHUTTER_WIDTH_UPPER);
 134         *data = ret << 16;
 135
 136         if (ret >= 0)
 137                 ret = reg_read(client, MT9T031_SHUTTER_WIDTH);
 138         *data |= ret & 0xffff;
 139
 140         return ret < 0 ? ret : 0;
 141 }
 142
 143 static int mt9t031_idle(struct i2c_client *client)
 144 {
 145         int ret;
 146
 147         /* Disable chip output, synchronous option update */
 148         ret = reg_write(client, MT9T031_RESET, 1);
 149         if (ret >= 0)
 150                 ret = reg_write(client, MT9T031_RESET, 0);
 151         if (ret >= 0)
 152                 ret = reg_clear(client, MT9T031_OUTPUT_CONTROL, 2);
 153
 154         return ret >= 0 ? 0 : -EIO;
 155 }
 156
 157 static int mt9t031_disable(struct i2c_client *client)
 158 {
 159         /* Disable the chip */
 160         reg_clear(client, MT9T031_OUTPUT_CONTROL, 2);
 161
 162         return 0;
 163 }
 164
 165 static int mt9t031_init(struct soc_camera_device *icd)
 166 {
 167         struct i2c_client *client = to_i2c_client(to_soc_camera_control(icd));
 168
 169         return mt9t031_idle(client);
 170 }
 171
 172 static int mt9t031_release(struct soc_camera_device *icd)
 173 {
 174         struct i2c_client *client = to_i2c_client(to_soc_camera_control(icd));
 175
 176         return mt9t031_disable(client);
 177 }
 178
 179 static int mt9t031_s_stream(struct v4l2_subdev *sd, int enable)
 180 {
 181         struct i2c_client *client = sd->priv;
 182         int ret;
 183
 184         if (enable)
 185                 /* Switch to master "normal" mode */
 186                 ret = reg_set(client, MT9T031_OUTPUT_CONTROL, 2);
 187         else
 188                 /* Stop sensor readout */
 189                 ret = reg_clear(client, MT9T031_OUTPUT_CONTROL, 2);
 190
 191         if (ret < 0)
 192                 return -EIO;
 193
 194         return 0;
 195 }
 196
 197 static int mt9t031_set_bus_param(struct soc_camera_device *icd,
 198                                  unsigned long flags)
 199 {
 200         struct i2c_client *client = to_i2c_client(to_soc_camera_control(icd));
 201
 202         /* The caller should have queried our parameters, check anyway */
 203         if (flags & ~MT9T031_BUS_PARAM)
 204                 return -EINVAL;
 205
 206         if (flags & SOCAM_PCLK_SAMPLE_FALLING)
 207                 reg_clear(client, MT9T031_PIXEL_CLOCK_CONTROL, 0x8000);
 208         else
 209                 reg_set(client, MT9T031_PIXEL_CLOCK_CONTROL, 0x8000);
 210
 211         return 0;
 212 }
 213
 214 static unsigned long mt9t031_query_bus_param(struct soc_camera_device *icd)
 215 {
 216         struct soc_camera_link *icl = to_soc_camera_link(icd);
 217
 218         return soc_camera_apply_sensor_flags(icl, MT9T031_BUS_PARAM);
 219 }
 220
 221 /* Round up minima and round down maxima */
 222 static void recalculate_limits(struct soc_camera_device *icd,
 223                                u16 xskip, u16 yskip)
 224 {
 225         icd->x_min = (MT9T031_COLUMN_SKIP + xskip - 1) / xskip;
 226         icd->y_min = (MT9T031_ROW_SKIP + yskip - 1) / yskip;
 227         icd->width_min = (MT9T031_MIN_WIDTH + xskip - 1) / xskip;
 228         icd->height_min = (MT9T031_MIN_HEIGHT + yskip - 1) / yskip;
 229         icd->width_max = MT9T031_MAX_WIDTH / xskip;
 230         icd->height_max = MT9T031_MAX_HEIGHT / yskip;
 231 }
 232
 233 static int mt9t031_set_params(struct soc_camera_device *icd,
 234                               struct v4l2_rect *rect, u16 xskip, u16 yskip)
 235 {
 236         struct i2c_client *client = to_i2c_client(to_soc_camera_control(icd));
 237         struct mt9t031 *mt9t031 = to_mt9t031(client);
 238         int ret;
 239         u16 xbin, ybin, width, height, left, top;
 240         const u16 hblank = MT9T031_HORIZONTAL_BLANK,
 241                 vblank = MT9T031_VERTICAL_BLANK;
 242
 243         /* Make sure we don't exceed sensor limits */
 244         if (rect->left + rect->width > icd->width_max)
 245                 rect->left = (icd->width_max - rect->width) / 2 + icd->x_min;
 246
 247         if (rect->top + rect->height > icd->height_max)
 248                 rect->top = (icd->height_max - rect->height) / 2 + icd->y_min;
 249
 250         width = rect->width * xskip;
 251         height = rect->height * yskip;
 252         left = rect->left * xskip;
 253         top = rect->top * yskip;
 254
 255         xbin = min(xskip, (u16)3);
 256         ybin = min(yskip, (u16)3);
 257
 258         dev_dbg(&icd->dev, "xskip %u, width %u/%u, yskip %u, height %u/%u\n",
 259                 xskip, width, rect->width, yskip, height, rect->height);
 260
 261         /* Could just do roundup(rect->left, [xy]bin * 2); but this is cheaper */
 262         switch (xbin) {
 263         case 2:
 264                 left = (left + 3) & ~3;
 265                 break;
 266         case 3:
 267                 left = roundup(left, 6);
 268         }
 269
 270         switch (ybin) {
 271         case 2:
 272                 top = (top + 3) & ~3;
 273                 break;
 274         case 3:
 275                 top = roundup(top, 6);
 276         }
 277
 278         /* Disable register update, reconfigure atomically */
 279         ret = reg_set(client, MT9T031_OUTPUT_CONTROL, 1);
 280         if (ret < 0)
 281                 return ret;
 282
 283         /* Blanking and start values - default... */
 284         ret = reg_write(client, MT9T031_HORIZONTAL_BLANKING, hblank);
 285         if (ret >= 0)
 286                 ret = reg_write(client, MT9T031_VERTICAL_BLANKING, vblank);
 287
 288         if (yskip != mt9t031->yskip || xskip != mt9t031->xskip) {
 289                 /* Binning, skipping */
 290                 if (ret >= 0)
 291                         ret = reg_write(client, MT9T031_COLUMN_ADDRESS_MODE,
 292                                         ((xbin - 1) << 4) | (xskip - 1));
 293                 if (ret >= 0)
 294                         ret = reg_write(client, MT9T031_ROW_ADDRESS_MODE,
 295                                         ((ybin - 1) << 4) | (yskip - 1));
 296         }
 297         dev_dbg(&icd->dev, "new physical left %u, top %u\n", left, top);
 298
 299         /* The caller provides a supported format, as guaranteed by
 300          * icd->try_fmt_cap(), soc_camera_s_crop() and soc_camera_cropcap() */
 301         if (ret >= 0)
 302                 ret = reg_write(client, MT9T031_COLUMN_START, left);
 303         if (ret >= 0)
 304                 ret = reg_write(client, MT9T031_ROW_START, top);
 305         if (ret >= 0)
 306                 ret = reg_write(client, MT9T031_WINDOW_WIDTH, width - 1);
 307         if (ret >= 0)
 308                 ret = reg_write(client, MT9T031_WINDOW_HEIGHT,
 309                                 height + icd->y_skip_top - 1);
 310         if (ret >= 0 && mt9t031->autoexposure) {
 311                 ret = set_shutter(client, height + icd->y_skip_top + vblank);
 312                 if (ret >= 0) {
 313                         const u32 shutter_max = MT9T031_MAX_HEIGHT + vblank;
 314                         const struct v4l2_queryctrl *qctrl =
 315                                 soc_camera_find_qctrl(icd->ops,
 316                                                       V4L2_CID_EXPOSURE);
 317                         icd->exposure = (shutter_max / 2 + (height +
 318                                          icd->y_skip_top + vblank - 1) *
 319                                          (qctrl->maximum - qctrl->minimum)) /
 320                                 shutter_max + qctrl->minimum;
 321                 }
 322         }
 323
 324         /* Re-enable register update, commit all changes */
 325         if (ret >= 0)
 326                 ret = reg_clear(client, MT9T031_OUTPUT_CONTROL, 1);
 327
 328         return ret < 0 ? ret : 0;
 329 }
 330
 331 static int mt9t031_set_crop(struct soc_camera_device *icd,
 332                             struct v4l2_rect *rect)
 333 {
 334         struct i2c_client *client = to_i2c_client(to_soc_camera_control(icd));
 335         struct mt9t031 *mt9t031 = to_mt9t031(client);
 336
 337         /* CROP - no change in scaling, or in limits */
 338         return mt9t031_set_params(icd, rect, mt9t031->xskip, mt9t031->yskip);
 339 }
 340
 341 static int mt9t031_s_fmt(struct v4l2_subdev *sd, struct v4l2_format *f)
 342 {
 343         struct i2c_client *client = sd->priv;
 344         struct mt9t031 *mt9t031 = to_mt9t031(client);
 345         struct soc_camera_device *icd = client->dev.platform_data;
 346         int ret;
 347         u16 xskip, yskip;
 348         struct v4l2_rect rect = {
 349                 .left   = icd->x_current,
 350                 .top    = icd->y_current,
 351                 .width  = f->fmt.pix.width,
 352                 .height = f->fmt.pix.height,
 353         };
 354
 355         /*
 356          * try_fmt has put rectangle within limits.
 357          * S_FMT - use binning and skipping for scaling, recalculate
 358          * limits, used for cropping
 359          */
 360         /* Is this more optimal than just a division? */
 361         for (xskip = 8; xskip > 1; xskip--)
 362                 if (rect.width * xskip <= MT9T031_MAX_WIDTH)
 363                         break;
 364
 365         for (yskip = 8; yskip > 1; yskip--)
 366                 if (rect.height * yskip <= MT9T031_MAX_HEIGHT)
 367                         break;
 368
 369         recalculate_limits(icd, xskip, yskip);
 370
 371         ret = mt9t031_set_params(icd, &rect, xskip, yskip);
 372         if (!ret) {
 373                 mt9t031->xskip = xskip;
 374                 mt9t031->yskip = yskip;
 375         }
 376
 377         return ret;
 378 }
 379
 380 static int mt9t031_try_fmt(struct v4l2_subdev *sd, struct v4l2_format *f)
 381 {
 382         struct v4l2_pix_format *pix = &f->fmt.pix;
 383
 384         v4l_bound_align_image(
 385                 &pix->width, MT9T031_MIN_WIDTH, MT9T031_MAX_WIDTH, 1,
 386                 &pix->height, MT9T031_MIN_HEIGHT, MT9T031_MAX_HEIGHT, 1, 0);
 387
 388         return 0;
 389 }
 390
 391 static int mt9t031_g_chip_ident(struct v4l2_subdev *sd,
 392                                 struct v4l2_dbg_chip_ident *id)
 393 {
 394         struct i2c_client *client = sd->priv;
 395         struct mt9t031 *mt9t031 = to_mt9t031(client);
 396
 397         if (id->match.type != V4L2_CHIP_MATCH_I2C_ADDR)
 398                 return -EINVAL;
 399
 400         if (id->match.addr != client->addr)
 401                 return -ENODEV;
 402
 403         id->ident       = mt9t031->model;
 404         id->revision    = 0;
 405
 406         return 0;
 407 }
 408
 409 #ifdef CONFIG_VIDEO_ADV_DEBUG
 410 static int mt9t031_g_register(struct v4l2_subdev *sd,
 411                               struct v4l2_dbg_register *reg)
 412 {
 413         struct i2c_client *client = sd->priv;
 414
 415         if (reg->match.type != V4L2_CHIP_MATCH_I2C_ADDR || reg->reg > 0xff)
 416                 return -EINVAL;
 417
 418         if (reg->match.addr != client->addr)
 419                 return -ENODEV;
 420
 421         reg->val = reg_read(client, reg->reg);
 422
 423         if (reg->val > 0xffff)
 424                 return -EIO;
 425
 426         return 0;
 427 }
 428
 429 static int mt9t031_s_register(struct v4l2_subdev *sd,
 430                               struct v4l2_dbg_register *reg)
 431 {
 432         struct i2c_client *client = sd->priv;
 433
 434         if (reg->match.type != V4L2_CHIP_MATCH_I2C_ADDR || reg->reg > 0xff)
 435                 return -EINVAL;
 436
 437         if (reg->match.addr != client->addr)
 438                 return -ENODEV;
 439
 440         if (reg_write(client, reg->reg, reg->val) < 0)
 441                 return -EIO;
 442
 443         return 0;
 444 }
 445 #endif
 446
 447 static const struct v4l2_queryctrl mt9t031_controls[] = {
 448         {
 449                 .id             = V4L2_CID_VFLIP,
 450                 .type           = V4L2_CTRL_TYPE_BOOLEAN,
 451                 .name           = "Flip Vertically",
 452                 .minimum        = 0,
 453                 .maximum        = 1,
 454                 .step           = 1,
 455                 .default_value  = 0,
 456         }, {
 457                 .id             = V4L2_CID_HFLIP,
 458                 .type           = V4L2_CTRL_TYPE_BOOLEAN,
 459                 .name           = "Flip Horizontally",
 460                 .minimum        = 0,
 461                 .maximum        = 1,
 462                 .step           = 1,
 463                 .default_value  = 0,
 464         }, {
 465                 .id             = V4L2_CID_GAIN,
 466                 .type           = V4L2_CTRL_TYPE_INTEGER,
 467                 .name           = "Gain",
 468                 .minimum        = 0,
 469                 .maximum        = 127,
 470                 .step           = 1,
 471                 .default_value  = 64,
 472                 .flags          = V4L2_CTRL_FLAG_SLIDER,
 473         }, {
 474                 .id             = V4L2_CID_EXPOSURE,
 475                 .type           = V4L2_CTRL_TYPE_INTEGER,
 476                 .name           = "Exposure",
 477                 .minimum        = 1,
 478                 .maximum        = 255,
 479                 .step           = 1,
 480                 .default_value  = 255,
 481                 .flags          = V4L2_CTRL_FLAG_SLIDER,
 482         }, {
 483                 .id             = V4L2_CID_EXPOSURE_AUTO,
 484                 .type           = V4L2_CTRL_TYPE_BOOLEAN,
 485                 .name           = "Automatic Exposure",
 486                 .minimum        = 0,
 487                 .maximum        = 1,
 488                 .step           = 1,
 489                 .default_value  = 1,
 490         }
 491 };
 492
 493 static struct soc_camera_ops mt9t031_ops = {
 494         .init                   = mt9t031_init,
 495         .release                = mt9t031_release,
 496         .set_crop               = mt9t031_set_crop,
 497         .set_bus_param          = mt9t031_set_bus_param,
 498         .query_bus_param        = mt9t031_query_bus_param,
 499         .controls               = mt9t031_controls,
 500         .num_controls           = ARRAY_SIZE(mt9t031_controls),
 501 };
 502
 503 static int mt9t031_g_ctrl(struct v4l2_subdev *sd, struct v4l2_control *ctrl)
 504 {
 505         struct i2c_client *client = sd->priv;
 506         struct mt9t031 *mt9t031 = to_mt9t031(client);
 507         int data;
 508
 509         switch (ctrl->id) {
 510         case V4L2_CID_VFLIP:
 511                 data = reg_read(client, MT9T031_READ_MODE_2);
 512                 if (data < 0)
 513                         return -EIO;
 514                 ctrl->value = !!(data & 0x8000);
 515                 break;
 516         case V4L2_CID_HFLIP:
 517                 data = reg_read(client, MT9T031_READ_MODE_2);
 518                 if (data < 0)
 519                         return -EIO;
 520                 ctrl->value = !!(data & 0x4000);
 521                 break;
 522         case V4L2_CID_EXPOSURE_AUTO:
 523                 ctrl->value = mt9t031->autoexposure;
 524                 break;
 525         }
 526         return 0;
 527 }
 528
 529 static int mt9t031_s_ctrl(struct v4l2_subdev *sd, struct v4l2_control *ctrl)
 530 {
 531         struct i2c_client *client = sd->priv;
 532         struct mt9t031 *mt9t031 = to_mt9t031(client);
 533         struct soc_camera_device *icd = client->dev.platform_data;
 534         const struct v4l2_queryctrl *qctrl;
 535         int data;
 536
 537         qctrl = soc_camera_find_qctrl(&mt9t031_ops, ctrl->id);
 538
 539         if (!qctrl)
 540                 return -EINVAL;
 541
 542         switch (ctrl->id) {
 543         case V4L2_CID_VFLIP:
 544                 if (ctrl->value)
 545                         data = reg_set(client, MT9T031_READ_MODE_2, 0x8000);
 546                 else
 547                         data = reg_clear(client, MT9T031_READ_MODE_2, 0x8000);
 548                 if (data < 0)
 549                         return -EIO;
 550                 break;
 551         case V4L2_CID_HFLIP:
 552                 if (ctrl->value)
 553                         data = reg_set(client, MT9T031_READ_MODE_2, 0x4000);
 554                 else
 555                         data = reg_clear(client, MT9T031_READ_MODE_2, 0x4000);
 556                 if (data < 0)
 557                         return -EIO;
 558                 break;
 559         case V4L2_CID_GAIN:
 560                 if (ctrl->value > qctrl->maximum || ctrl->value < qctrl->minimum)
 561                         return -EINVAL;
 562                 /* See Datasheet Table 7, Gain settings. */
 563                 if (ctrl->value <= qctrl->default_value) {
 564                         /* Pack it into 0..1 step 0.125, register values 0..8 */
 565                         unsigned long range = qctrl->default_value - qctrl->minimum;
 566                         data = ((ctrl->value - qctrl->minimum) * 8 + range / 2) / range;
 567
 568                         dev_dbg(&icd->dev, "Setting gain %d\n", data);
 569                         data = reg_write(client, MT9T031_GLOBAL_GAIN, data);
 570                         if (data < 0)
 571                                 return -EIO;
 572                 } else {
 573                         /* Pack it into 1.125..128 variable step, register values 9..0x7860 */
 574                         /* We assume qctrl->maximum - qctrl->default_value - 1 > 0 */
 575                         unsigned long range = qctrl->maximum - qctrl->default_value - 1;
 576                         /* calculated gain: map 65..127 to 9..1024 step 0.125 */
 577                         unsigned long gain = ((ctrl->value - qctrl->default_value - 1) *
 578                                                1015 + range / 2) / range + 9;
 579
 580                         if (gain <= 32)         /* calculated gain 9..32 -> 9..32 */
 581                                 data = gain;
 582                         else if (gain <= 64)    /* calculated gain 33..64 -> 0x51..0x60 */
 583                                 data = ((gain - 32) * 16 + 16) / 32 + 80;
 584                         else
 585                                 /* calculated gain 65..1024 -> (1..120) << 8 + 0x60 */
 586                                 data = (((gain - 64 + 7) * 32) & 0xff00) | 0x60;
 587
 588                         dev_dbg(&icd->dev, "Setting gain from 0x%x to 0x%x\n",
 589                                 reg_read(client, MT9T031_GLOBAL_GAIN), data);
 590                         data = reg_write(client, MT9T031_GLOBAL_GAIN, data);
 591                         if (data < 0)
 592                                 return -EIO;
 593                 }
 594
 595                 /* Success */
 596                 icd->gain = ctrl->value;
 597                 break;
 598         case V4L2_CID_EXPOSURE:
 599                 /* mt9t031 has maximum == default */
 600                 if (ctrl->value > qctrl->maximum || ctrl->value < qctrl->minimum)
 601                         return -EINVAL;
 602                 else {
 603                         const unsigned long range = qctrl->maximum - qctrl->minimum;
 604                         const u32 shutter = ((ctrl->value - qctrl->minimum) * 1048 +
 605                                              range / 2) / range + 1;
 606                         u32 old;
 607
 608                         get_shutter(client, &old);
 609                         dev_dbg(&icd->dev, "Setting shutter width from %u to %u\n",
 610                                 old, shutter);
 611                         if (set_shutter(client, shutter) < 0)
 612                                 return -EIO;
 613                         icd->exposure = ctrl->value;
 614                         mt9t031->autoexposure = 0;
 615                 }
 616                 break;
 617         case V4L2_CID_EXPOSURE_AUTO:
 618                 if (ctrl->value) {
 619                         const u16 vblank = MT9T031_VERTICAL_BLANK;
 620                         const u32 shutter_max = MT9T031_MAX_HEIGHT + vblank;
 621                         if (set_shutter(client, icd->height +
 622                                         icd->y_skip_top + vblank) < 0)
 623                                 return -EIO;
 624                         qctrl = soc_camera_find_qctrl(icd->ops, V4L2_CID_EXPOSURE);
 625                         icd->exposure = (shutter_max / 2 + (icd->height +
 626                                          icd->y_skip_top + vblank - 1) *
 627                                          (qctrl->maximum - qctrl->minimum)) /
 628                                 shutter_max + qctrl->minimum;
 629                         mt9t031->autoexposure = 1;
 630                 } else
 631                         mt9t031->autoexposure = 0;
 632                 break;
 633         }
 634         return 0;
 635 }
 636
 637 /* Interface active, can use i2c. If it fails, it can indeed mean, that
 638  * this wasn't our capture interface, so, we wait for the right one */
 639 static int mt9t031_video_probe(struct i2c_client *client)
 640 {
 641         struct soc_camera_device *icd = client->dev.platform_data;
 642         struct mt9t031 *mt9t031 = to_mt9t031(client);
 643         s32 data;
 644
 645         /* We must have a parent by now. And it cannot be a wrong one.
 646          * So this entire test is completely redundant. */
 647         if (!icd->dev.parent ||
 648             to_soc_camera_host(icd->dev.parent)->nr != icd->iface)
 649                 return -ENODEV;
 650
 651         /* Enable the chip */
 652         data = reg_write(client, MT9T031_CHIP_ENABLE, 1);
 653         dev_dbg(&icd->dev, "write: %d\n", data);
 654
 655         /* Read out the chip version register */
 656         data = reg_read(client, MT9T031_CHIP_VERSION);
 657
 658         switch (data) {
 659         case 0x1621:
 660                 mt9t031->model = V4L2_IDENT_MT9T031;
 661                 icd->formats = mt9t031_colour_formats;
 662                 icd->num_formats = ARRAY_SIZE(mt9t031_colour_formats);
 663                 break;
 664         default:
 665                 dev_err(&icd->dev,
 666                         "No MT9T031 chip detected, register read %x\n", data);
 667                 return -ENODEV;
 668         }
 669
 670         dev_info(&icd->dev, "Detected a MT9T031 chip ID %x\n", data);
 671
 672         return 0;
 673 }
 674
 675 static struct v4l2_subdev_core_ops mt9t031_subdev_core_ops = {
 676         .g_ctrl         = mt9t031_g_ctrl,
 677         .s_ctrl         = mt9t031_s_ctrl,
 678         .g_chip_ident   = mt9t031_g_chip_ident,
 679 #ifdef CONFIG_VIDEO_ADV_DEBUG
 680         .g_register     = mt9t031_g_register,
 681         .s_register     = mt9t031_s_register,
 682 #endif
 683 };
 684
 685 static struct v4l2_subdev_video_ops mt9t031_subdev_video_ops = {
 686         .s_stream       = mt9t031_s_stream,
 687         .s_fmt          = mt9t031_s_fmt,
 688         .try_fmt        = mt9t031_try_fmt,
 689 };
 690
 691 static struct v4l2_subdev_ops mt9t031_subdev_ops = {
 692         .core   = &mt9t031_subdev_core_ops,
 693         .video  = &mt9t031_subdev_video_ops,
 694 };
 695
 696 static int mt9t031_probe(struct i2c_client *client,
 697                          const struct i2c_device_id *did)
 698 {
 699         struct mt9t031 *mt9t031;
 700         struct soc_camera_device *icd = client->dev.platform_data;
 701         struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
 702         struct soc_camera_link *icl;
 703         int ret;
 704
 705         if (!icd) {
 706                 dev_err(&client->dev, "MT9T031: missing soc-camera data!\n");
 707                 return -EINVAL;
 708         }
 709
 710         icl = to_soc_camera_link(icd);
 711         if (!icl) {
 712                 dev_err(&client->dev, "MT9T031 driver needs platform data\n");
 713                 return -EINVAL;
 714         }
 715
 716         if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA)) {
 717                 dev_warn(&adapter->dev,
 718                          "I2C-Adapter doesn't support I2C_FUNC_SMBUS_WORD\n");
 719                 return -EIO;
 720         }
 721
 722         mt9t031 = kzalloc(sizeof(struct mt9t031), GFP_KERNEL);
 723         if (!mt9t031)
 724                 return -ENOMEM;
 725
 726         v4l2_i2c_subdev_init(&mt9t031->subdev, client, &mt9t031_subdev_ops);
 727
 728         /* Second stage probe - when a capture adapter is there */
 729         icd->ops        = &mt9t031_ops;
 730         icd->x_min      = MT9T031_COLUMN_SKIP;
 731         icd->y_min      = MT9T031_ROW_SKIP;
 732         icd->x_current  = icd->x_min;
 733         icd->y_current  = icd->y_min;
 734         icd->width_min  = MT9T031_MIN_WIDTH;
 735         icd->width_max  = MT9T031_MAX_WIDTH;
 736         icd->height_min = MT9T031_MIN_HEIGHT;
 737         icd->height_max = MT9T031_MAX_HEIGHT;
 738         icd->y_skip_top = 0;
 739         /* Simulated autoexposure. If enabled, we calculate shutter width
 740          * ourselves in the driver based on vertical blanking and frame width */
 741         mt9t031->autoexposure = 1;
 742
 743         mt9t031->xskip = 1;
 744         mt9t031->yskip = 1;
 745
 746         mt9t031_idle(client);
 747
 748         ret = mt9t031_video_probe(client);
 749
 750         mt9t031_disable(client);
 751
 752         if (ret) {
 753                 icd->ops = NULL;
 754                 i2c_set_clientdata(client, NULL);
 755                 kfree(mt9t031);
 756         }
 757
 758         return ret;
 759 }
 760
 761 static int mt9t031_remove(struct i2c_client *client)
 762 {
 763         struct mt9t031 *mt9t031 = to_mt9t031(client);
 764         struct soc_camera_device *icd = client->dev.platform_data;
 765
 766         icd->ops = NULL;
 767         i2c_set_clientdata(client, NULL);
 768         client->driver = NULL;
 769         kfree(mt9t031);
 770
 771         return 0;
 772 }
 773
 774 static const struct i2c_device_id mt9t031_id[] = {
 775         { "mt9t031", 0 },
 776         { }
 777 };
 778 MODULE_DEVICE_TABLE(i2c, mt9t031_id);
 779
 780 static struct i2c_driver mt9t031_i2c_driver = {
 781         .driver = {
 782                 .name = "mt9t031",
 783         },
 784         .probe          = mt9t031_probe,
 785         .remove         = mt9t031_remove,
 786         .id_table       = mt9t031_id,
 787 };
 788
 789 static int __init mt9t031_mod_init(void)
 790 {
 791         return i2c_add_driver(&mt9t031_i2c_driver);
 792 }
 793
 794 static void __exit mt9t031_mod_exit(void)
 795 {
 796         i2c_del_driver(&mt9t031_i2c_driver);
 797 }
 798
 799 module_init(mt9t031_mod_init);
 800 module_exit(mt9t031_mod_exit);
 801
 802 MODULE_DESCRIPTION("Micron MT9T031 Camera driver");
 803 MODULE_AUTHOR("Guennadi Liakhovetski <lg@denx.de>");
 804 MODULE_LICENSE("GPL v2");