drivers/media/video/ovcamchip/ovcamchip_core.c

   1 /* Shared Code for OmniVision Camera Chip Drivers
   2  *
   3  * Copyright (c) 2004 Mark McClelland <mark@alpha.dyndns.org>
   4  * http://alpha.dyndns.org/ov511/
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License as published by the
   8  * Free Software Foundation; either version 2 of the License, or (at your
   9  * option) any later version. NO WARRANTY OF ANY KIND is expressed or implied.
  10  */
  11
  12 #define DEBUG
  13
  14 #include <linux/init.h>
  15 #include <linux/module.h>
  16 #include <linux/slab.h>
  17 #include <linux/delay.h>
  18 #include <linux/i2c.h>
  19 #include <media/v4l2-device.h>
  20 #include <media/v4l2-i2c-drv.h>
  21 #include "ovcamchip_priv.h"
  22
  23 #define DRIVER_VERSION "v2.27 for Linux 2.6"
  24 #define DRIVER_AUTHOR "Mark McClelland <mark@alpha.dyndns.org>"
  25 #define DRIVER_DESC "OV camera chip I2C driver"
  26
  27 #define PINFO(fmt, args...) printk(KERN_INFO "ovcamchip: " fmt "\n" , ## args);
  28 #define PERROR(fmt, args...) printk(KERN_ERR "ovcamchip: " fmt "\n" , ## args);
  29
  30 #ifdef DEBUG
  31 int ovcamchip_debug = 0;
  32 static int debug;
  33 module_param(debug, int, 0);
  34 MODULE_PARM_DESC(debug,
  35   "Debug level: 0=none, 1=inits, 2=warning, 3=config, 4=functions, 5=all");
  36 #endif
  37
  38 /* By default, let bridge driver tell us if chip is monochrome. mono=0
  39  * will ignore that and always treat chips as color. mono=1 will force
  40  * monochrome mode for all chips. */
  41 static int mono = -1;
  42 module_param(mono, int, 0);
  43 MODULE_PARM_DESC(mono,
  44   "1=chips are monochrome (OVx1xx), 0=force color, -1=autodetect (default)");
  45
  46 MODULE_AUTHOR(DRIVER_AUTHOR);
  47 MODULE_DESCRIPTION(DRIVER_DESC);
  48 MODULE_LICENSE("GPL");
  49
  50
  51 /* Registers common to all chips, that are needed for detection */
  52 #define GENERIC_REG_ID_HIGH       0x1C  /* manufacturer ID MSB */
  53 #define GENERIC_REG_ID_LOW        0x1D  /* manufacturer ID LSB */
  54 #define GENERIC_REG_COM_I         0x29  /* misc ID bits */
  55
  56 static char *chip_names[NUM_CC_TYPES] = {
  57         [CC_UNKNOWN]    = "Unknown chip",
  58         [CC_OV76BE]     = "OV76BE",
  59         [CC_OV7610]     = "OV7610",
  60         [CC_OV7620]     = "OV7620",
  61         [CC_OV7620AE]   = "OV7620AE",
  62         [CC_OV6620]     = "OV6620",
  63         [CC_OV6630]     = "OV6630",
  64         [CC_OV6630AE]   = "OV6630AE",
  65         [CC_OV6630AF]   = "OV6630AF",
  66 };
  67
  68 /* ----------------------------------------------------------------------- */
  69
  70 int ov_write_regvals(struct i2c_client *c, struct ovcamchip_regvals *rvals)
  71 {
  72         int rc;
  73
  74         while (rvals->reg != 0xff) {
  75                 rc = ov_write(c, rvals->reg, rvals->val);
  76                 if (rc < 0)
  77                         return rc;
  78                 rvals++;
  79         }
  80
  81         return 0;
  82 }
  83
  84 /* Writes bits at positions specified by mask to an I2C reg. Bits that are in
  85  * the same position as 1's in "mask" are cleared and set to "value". Bits
  86  * that are in the same position as 0's in "mask" are preserved, regardless
  87  * of their respective state in "value".
  88  */
  89 int ov_write_mask(struct i2c_client *c,
  90                   unsigned char reg,
  91                   unsigned char value,
  92                   unsigned char mask)
  93 {
  94         int rc;
  95         unsigned char oldval, newval;
  96
  97         if (mask == 0xff) {
  98                 newval = value;
  99         } else {
 100                 rc = ov_read(c, reg, &oldval);
 101                 if (rc < 0)
 102                         return rc;
 103
 104                 oldval &= (~mask);              /* Clear the masked bits */
 105                 value &= mask;                  /* Enforce mask on value */
 106                 newval = oldval | value;        /* Set the desired bits */
 107         }
 108
 109         return ov_write(c, reg, newval);
 110 }
 111
 112 /* ----------------------------------------------------------------------- */
 113
 114 /* Reset the chip and ensure that I2C is synchronized. Returns <0 if failure.
 115  */
 116 static int init_camchip(struct i2c_client *c)
 117 {
 118         int i, success;
 119         unsigned char high, low;
 120
 121         /* Reset the chip */
 122         ov_write(c, 0x12, 0x80);
 123
 124         /* Wait for it to initialize */
 125         msleep(150);
 126
 127         for (i = 0, success = 0; i < I2C_DETECT_RETRIES && !success; i++) {
 128                 if (ov_read(c, GENERIC_REG_ID_HIGH, &high) >= 0) {
 129                         if (ov_read(c, GENERIC_REG_ID_LOW, &low) >= 0) {
 130                                 if (high == 0x7F && low == 0xA2) {
 131                                         success = 1;
 132                                         continue;
 133                                 }
 134                         }
 135                 }
 136
 137                 /* Reset the chip */
 138                 ov_write(c, 0x12, 0x80);
 139
 140                 /* Wait for it to initialize */
 141                 msleep(150);
 142
 143                 /* Dummy read to sync I2C */
 144                 ov_read(c, 0x00, &low);
 145         }
 146
 147         if (!success)
 148                 return -EIO;
 149
 150         PDEBUG(1, "I2C synced in %d attempt(s)", i);
 151
 152         return 0;
 153 }
 154
 155 /* This detects the OV7610, OV7620, or OV76BE chip. */
 156 static int ov7xx0_detect(struct i2c_client *c)
 157 {
 158         struct ovcamchip *ov = i2c_get_clientdata(c);
 159         int rc;
 160         unsigned char val;
 161
 162         PDEBUG(4, "");
 163
 164         /* Detect chip (sub)type */
 165         rc = ov_read(c, GENERIC_REG_COM_I, &val);
 166         if (rc < 0) {
 167                 PERROR("Error detecting ov7xx0 type");
 168                 return rc;
 169         }
 170
 171         if ((val & 3) == 3) {
 172                 PINFO("Camera chip is an OV7610");
 173                 ov->subtype = CC_OV7610;
 174         } else if ((val & 3) == 1) {
 175                 rc = ov_read(c, 0x15, &val);
 176                 if (rc < 0) {
 177                         PERROR("Error detecting ov7xx0 type");
 178                         return rc;
 179                 }
 180
 181                 if (val & 1) {
 182                         PINFO("Camera chip is an OV7620AE");
 183                         /* OV7620 is a close enough match for now. There are
 184                          * some definite differences though, so this should be
 185                          * fixed */
 186                         ov->subtype = CC_OV7620;
 187                 } else {
 188                         PINFO("Camera chip is an OV76BE");
 189                         ov->subtype = CC_OV76BE;
 190                 }
 191         } else if ((val & 3) == 0) {
 192                 PINFO("Camera chip is an OV7620");
 193                 ov->subtype = CC_OV7620;
 194         } else {
 195                 PERROR("Unknown camera chip version: %d", val & 3);
 196                 return -ENOSYS;
 197         }
 198
 199         if (ov->subtype == CC_OV76BE)
 200                 ov->sops = &ov76be_ops;
 201         else if (ov->subtype == CC_OV7620)
 202                 ov->sops = &ov7x20_ops;
 203         else
 204                 ov->sops = &ov7x10_ops;
 205
 206         return 0;
 207 }
 208
 209 /* This detects the OV6620, OV6630, OV6630AE, or OV6630AF chip. */
 210 static int ov6xx0_detect(struct i2c_client *c)
 211 {
 212         struct ovcamchip *ov = i2c_get_clientdata(c);
 213         int rc;
 214         unsigned char val;
 215
 216         PDEBUG(4, "");
 217
 218         /* Detect chip (sub)type */
 219         rc = ov_read(c, GENERIC_REG_COM_I, &val);
 220         if (rc < 0) {
 221                 PERROR("Error detecting ov6xx0 type");
 222                 return -1;
 223         }
 224
 225         if ((val & 3) == 0) {
 226                 ov->subtype = CC_OV6630;
 227                 PINFO("Camera chip is an OV6630");
 228         } else if ((val & 3) == 1) {
 229                 ov->subtype = CC_OV6620;
 230                 PINFO("Camera chip is an OV6620");
 231         } else if ((val & 3) == 2) {
 232                 ov->subtype = CC_OV6630;
 233                 PINFO("Camera chip is an OV6630AE");
 234         } else if ((val & 3) == 3) {
 235                 ov->subtype = CC_OV6630;
 236                 PINFO("Camera chip is an OV6630AF");
 237         }
 238
 239         if (ov->subtype == CC_OV6620)
 240                 ov->sops = &ov6x20_ops;
 241         else
 242                 ov->sops = &ov6x30_ops;
 243
 244         return 0;
 245 }
 246
 247 static int ovcamchip_detect(struct i2c_client *c)
 248 {
 249         /* Ideally we would just try a single register write and see if it NAKs.
 250          * That isn't possible since the OV518 can't report I2C transaction
 251          * failures. So, we have to try to initialize the chip (i.e. reset it
 252          * and check the ID registers) to detect its presence. */
 253
 254         /* Test for 7xx0 */
 255         PDEBUG(3, "Testing for 0V7xx0");
 256         if (init_camchip(c) < 0)
 257                 return -ENODEV;
 258         /* 7-bit addresses with bit 0 set are for the OV7xx0 */
 259         if (c->addr & 1) {
 260                 if (ov7xx0_detect(c) < 0) {
 261                         PERROR("Failed to init OV7xx0");
 262                         return -EIO;
 263                 }
 264                 return 0;
 265         }
 266         /* Test for 6xx0 */
 267         PDEBUG(3, "Testing for 0V6xx0");
 268         if (ov6xx0_detect(c) < 0) {
 269                 PERROR("Failed to init OV6xx0");
 270                 return -EIO;
 271         }
 272         return 0;
 273 }
 274
 275 /* ----------------------------------------------------------------------- */
 276
 277 static long ovcamchip_ioctl(struct v4l2_subdev *sd, unsigned int cmd, void *arg)
 278 {
 279         struct ovcamchip *ov = to_ovcamchip(sd);
 280         struct i2c_client *c = v4l2_get_subdevdata(sd);
 281
 282         if (!ov->initialized &&
 283             cmd != OVCAMCHIP_CMD_Q_SUBTYPE &&
 284             cmd != OVCAMCHIP_CMD_INITIALIZE) {
 285                 v4l2_err(sd, "Camera chip not initialized yet!\n");
 286                 return -EPERM;
 287         }
 288
 289         switch (cmd) {
 290         case OVCAMCHIP_CMD_Q_SUBTYPE:
 291         {
 292                 *(int *)arg = ov->subtype;
 293                 return 0;
 294         }
 295         case OVCAMCHIP_CMD_INITIALIZE:
 296         {
 297                 int rc;
 298
 299                 if (mono == -1)
 300                         ov->mono = *(int *)arg;
 301                 else
 302                         ov->mono = mono;
 303
 304                 if (ov->mono) {
 305                         if (ov->subtype != CC_OV7620)
 306                                 v4l2_warn(sd, "Monochrome not "
 307                                         "implemented for this chip\n");
 308                         else
 309                                 v4l2_info(sd, "Initializing chip as "
 310                                         "monochrome\n");
 311                 }
 312
 313                 rc = ov->sops->init(c);
 314                 if (rc < 0)
 315                         return rc;
 316
 317                 ov->initialized = 1;
 318                 return 0;
 319         }
 320         default:
 321                 return ov->sops->command(c, cmd, arg);
 322         }
 323 }
 324
 325 /* ----------------------------------------------------------------------- */
 326
 327 static const struct v4l2_subdev_core_ops ovcamchip_core_ops = {
 328         .ioctl = ovcamchip_ioctl,
 329 };
 330
 331 static const struct v4l2_subdev_ops ovcamchip_ops = {
 332         .core = &ovcamchip_core_ops,
 333 };
 334
 335 static int ovcamchip_probe(struct i2c_client *client,
 336                         const struct i2c_device_id *id)
 337 {
 338         struct ovcamchip *ov;
 339         struct v4l2_subdev *sd;
 340         int rc = 0;
 341
 342         ov = kzalloc(sizeof *ov, GFP_KERNEL);
 343         if (!ov) {
 344                 rc = -ENOMEM;
 345                 goto no_ov;
 346         }
 347         sd = &ov->sd;
 348         v4l2_i2c_subdev_init(sd, client, &ovcamchip_ops);
 349
 350         rc = ovcamchip_detect(client);
 351         if (rc < 0)
 352                 goto error;
 353
 354         v4l_info(client, "%s found @ 0x%02x (%s)\n",
 355                         chip_names[ov->subtype], client->addr << 1, client->adapter->name);
 356
 357         PDEBUG(1, "Camera chip detection complete");
 358
 359         return rc;
 360 error:
 361         kfree(ov);
 362 no_ov:
 363         PDEBUG(1, "returning %d", rc);
 364         return rc;
 365 }
 366
 367 static int ovcamchip_remove(struct i2c_client *client)
 368 {
 369         struct v4l2_subdev *sd = i2c_get_clientdata(client);
 370         struct ovcamchip *ov = to_ovcamchip(sd);
 371         int rc;
 372
 373         v4l2_device_unregister_subdev(sd);
 374         rc = ov->sops->free(client);
 375         if (rc < 0)
 376                 return rc;
 377
 378         kfree(ov);
 379         return 0;
 380 }
 381
 382 /* ----------------------------------------------------------------------- */
 383
 384 static const struct i2c_device_id ovcamchip_id[] = {
 385         { "ovcamchip", 0 },
 386         { }
 387 };
 388 MODULE_DEVICE_TABLE(i2c, ovcamchip_id);
 389
 390 static struct v4l2_i2c_driver_data v4l2_i2c_data = {
 391         .name = "ovcamchip",
 392         .probe = ovcamchip_probe,
 393         .remove = ovcamchip_remove,
 394         .id_table = ovcamchip_id,
 395 };