drivers/media/video/em28xx/em28xx-i2c.c

   1 /*
   2    em28xx-i2c.c - driver for Empia EM2800/EM2820/2840 USB video capture devices
   3
   4    Copyright (C) 2005 Ludovico Cavedon <cavedon@sssup.it>
   5                       Markus Rechberger <mrechberger@gmail.com>
   6                       Mauro Carvalho Chehab <mchehab@infradead.org>
   7                       Sascha Sommer <saschasommer@freenet.de>
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 2 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program; if not, write to the Free Software
  21    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  22  */
  23
  24 #include <linux/module.h>
  25 #include <linux/kernel.h>
  26 #include <linux/usb.h>
  27 #include <linux/i2c.h>
  28
  29 #include "em28xx.h"
  30 #include "tuner-xc2028.h"
  31 #include <media/v4l2-common.h>
  32 #include <media/tuner.h>
  33
  34 /* ----------------------------------------------------------- */
  35
  36 static unsigned int i2c_scan;
  37 module_param(i2c_scan, int, 0444);
  38 MODULE_PARM_DESC(i2c_scan, "scan i2c bus at insmod time");
  39
  40 static unsigned int i2c_debug;
  41 module_param(i2c_debug, int, 0644);
  42 MODULE_PARM_DESC(i2c_debug, "enable debug messages [i2c]");
  43
  44
  45 #define dprintk1(lvl, fmt, args...)                     \
  46 do {                                                    \
  47         if (i2c_debug >= lvl) {                         \
  48         printk(fmt, ##args);                            \
  49       }                                                 \
  50 } while (0)
  51
  52 #define dprintk2(lvl, fmt, args...)                     \
  53 do {                                                    \
  54         if (i2c_debug >= lvl) {                         \
  55                 printk(KERN_DEBUG "%s at %s: " fmt,     \
  56                        dev->name, __func__ , ##args);   \
  57       }                                                 \
  58 } while (0)
  59
  60 /*
  61  * em2800_i2c_send_max4()
  62  * send up to 4 bytes to the i2c device
  63  */
  64 static int em2800_i2c_send_max4(struct em28xx *dev, unsigned char addr,
  65                                 char *buf, int len)
  66 {
  67         int ret;
  68         int write_timeout;
  69         unsigned char b2[6];
  70         BUG_ON(len < 1 || len > 4);
  71         b2[5] = 0x80 + len - 1;
  72         b2[4] = addr;
  73         b2[3] = buf[0];
  74         if (len > 1)
  75                 b2[2] = buf[1];
  76         if (len > 2)
  77                 b2[1] = buf[2];
  78         if (len > 3)
  79                 b2[0] = buf[3];
  80
  81         ret = dev->em28xx_write_regs(dev, 4 - len, &b2[4 - len], 2 + len);
  82         if (ret != 2 + len) {
  83                 em28xx_warn("writing to i2c device failed (error=%i)\n", ret);
  84                 return -EIO;
  85         }
  86         for (write_timeout = EM2800_I2C_WRITE_TIMEOUT; write_timeout > 0;
  87              write_timeout -= 5) {
  88                 ret = dev->em28xx_read_reg(dev, 0x05);
  89                 if (ret == 0x80 + len - 1)
  90                         return len;
  91                 msleep(5);
  92         }
  93         em28xx_warn("i2c write timed out\n");
  94         return -EIO;
  95 }
  96
  97 /*
  98  * em2800_i2c_send_bytes()
  99  */
 100 static int em2800_i2c_send_bytes(void *data, unsigned char addr, char *buf,
 101                                  short len)
 102 {
 103         char *bufPtr = buf;
 104         int ret;
 105         int wrcount = 0;
 106         int count;
 107         int maxLen = 4;
 108         struct em28xx *dev = (struct em28xx *)data;
 109         while (len > 0) {
 110                 count = (len > maxLen) ? maxLen : len;
 111                 ret = em2800_i2c_send_max4(dev, addr, bufPtr, count);
 112                 if (ret > 0) {
 113                         len -= count;
 114                         bufPtr += count;
 115                         wrcount += count;
 116                 } else
 117                         return (ret < 0) ? ret : -EFAULT;
 118         }
 119         return wrcount;
 120 }
 121
 122 /*
 123  * em2800_i2c_check_for_device()
 124  * check if there is a i2c_device at the supplied address
 125  */
 126 static int em2800_i2c_check_for_device(struct em28xx *dev, unsigned char addr)
 127 {
 128         char msg;
 129         int ret;
 130         int write_timeout;
 131         msg = addr;
 132         ret = dev->em28xx_write_regs(dev, 0x04, &msg, 1);
 133         if (ret < 0) {
 134                 em28xx_warn("setting i2c device address failed (error=%i)\n",
 135                             ret);
 136                 return ret;
 137         }
 138         msg = 0x84;
 139         ret = dev->em28xx_write_regs(dev, 0x05, &msg, 1);
 140         if (ret < 0) {
 141                 em28xx_warn("preparing i2c read failed (error=%i)\n", ret);
 142                 return ret;
 143         }
 144         for (write_timeout = EM2800_I2C_WRITE_TIMEOUT; write_timeout > 0;
 145              write_timeout -= 5) {
 146                 unsigned reg = dev->em28xx_read_reg(dev, 0x5);
 147
 148                 if (reg == 0x94)
 149                         return -ENODEV;
 150                 else if (reg == 0x84)
 151                         return 0;
 152                 msleep(5);
 153         }
 154         return -ENODEV;
 155 }
 156
 157 /*
 158  * em2800_i2c_recv_bytes()
 159  * read from the i2c device
 160  */
 161 static int em2800_i2c_recv_bytes(struct em28xx *dev, unsigned char addr,
 162                                  char *buf, int len)
 163 {
 164         int ret;
 165         /* check for the device and set i2c read address */
 166         ret = em2800_i2c_check_for_device(dev, addr);
 167         if (ret) {
 168                 em28xx_warn
 169                     ("preparing read at i2c address 0x%x failed (error=%i)\n",
 170                      addr, ret);
 171                 return ret;
 172         }
 173         ret = dev->em28xx_read_reg_req_len(dev, 0x0, 0x3, buf, len);
 174         if (ret < 0) {
 175                 em28xx_warn("reading from i2c device at 0x%x failed (error=%i)",
 176                             addr, ret);
 177                 return ret;
 178         }
 179         return ret;
 180 }
 181
 182 /*
 183  * em28xx_i2c_send_bytes()
 184  * untested for more than 4 bytes
 185  */
 186 static int em28xx_i2c_send_bytes(void *data, unsigned char addr, char *buf,
 187                                  short len, int stop)
 188 {
 189         int wrcount = 0;
 190         struct em28xx *dev = (struct em28xx *)data;
 191
 192         wrcount = dev->em28xx_write_regs_req(dev, stop ? 2 : 3, addr, buf, len);
 193
 194         return wrcount;
 195 }
 196
 197 /*
 198  * em28xx_i2c_recv_bytes()
 199  * read a byte from the i2c device
 200  */
 201 static int em28xx_i2c_recv_bytes(struct em28xx *dev, unsigned char addr,
 202                                  char *buf, int len)
 203 {
 204         int ret;
 205         ret = dev->em28xx_read_reg_req_len(dev, 2, addr, buf, len);
 206         if (ret < 0) {
 207                 em28xx_warn("reading i2c device failed (error=%i)\n", ret);
 208                 return ret;
 209         }
 210         if (dev->em28xx_read_reg(dev, 0x5) != 0)
 211                 return -ENODEV;
 212         return ret;
 213 }
 214
 215 /*
 216  * em28xx_i2c_check_for_device()
 217  * check if there is a i2c_device at the supplied address
 218  */
 219 static int em28xx_i2c_check_for_device(struct em28xx *dev, unsigned char addr)
 220 {
 221         char msg;
 222         int ret;
 223         msg = addr;
 224
 225         ret = dev->em28xx_read_reg_req(dev, 2, addr);
 226         if (ret < 0) {
 227                 em28xx_warn("reading from i2c device failed (error=%i)\n", ret);
 228                 return ret;
 229         }
 230         if (dev->em28xx_read_reg(dev, 0x5) != 0)
 231                 return -ENODEV;
 232         return 0;
 233 }
 234
 235 /*
 236  * em28xx_i2c_xfer()
 237  * the main i2c transfer function
 238  */
 239 static int em28xx_i2c_xfer(struct i2c_adapter *i2c_adap,
 240                            struct i2c_msg msgs[], int num)
 241 {
 242         struct em28xx *dev = i2c_adap->algo_data;
 243         int addr, rc, i, byte;
 244
 245         if (num <= 0)
 246                 return 0;
 247         for (i = 0; i < num; i++) {
 248                 addr = msgs[i].addr << 1;
 249                 dprintk2(2, "%s %s addr=%x len=%d:",
 250                          (msgs[i].flags & I2C_M_RD) ? "read" : "write",
 251                          i == num - 1 ? "stop" : "nonstop", addr, msgs[i].len);
 252                 if (!msgs[i].len) { /* no len: check only for device presence */
 253                         if (dev->is_em2800)
 254                                 rc = em2800_i2c_check_for_device(dev, addr);
 255                         else
 256                                 rc = em28xx_i2c_check_for_device(dev, addr);
 257                         if (rc < 0) {
 258                                 dprintk2(2, " no device\n");
 259                                 return rc;
 260                         }
 261
 262                 } else if (msgs[i].flags & I2C_M_RD) {
 263                         /* read bytes */
 264                         if (dev->is_em2800)
 265                                 rc = em2800_i2c_recv_bytes(dev, addr,
 266                                                            msgs[i].buf,
 267                                                            msgs[i].len);
 268                         else
 269                                 rc = em28xx_i2c_recv_bytes(dev, addr,
 270                                                            msgs[i].buf,
 271                                                            msgs[i].len);
 272                         if (i2c_debug >= 2) {
 273                                 for (byte = 0; byte < msgs[i].len; byte++)
 274                                         printk(" %02x", msgs[i].buf[byte]);
 275                         }
 276                 } else {
 277                         /* write bytes */
 278                         if (i2c_debug >= 2) {
 279                                 for (byte = 0; byte < msgs[i].len; byte++)
 280                                         printk(" %02x", msgs[i].buf[byte]);
 281                         }
 282                         if (dev->is_em2800)
 283                                 rc = em2800_i2c_send_bytes(dev, addr,
 284                                                            msgs[i].buf,
 285                                                            msgs[i].len);
 286                         else
 287                                 rc = em28xx_i2c_send_bytes(dev, addr,
 288                                                            msgs[i].buf,
 289                                                            msgs[i].len,
 290                                                            i == num - 1);
 291                 }
 292                 if (rc < 0)
 293                         goto err;
 294                 if (i2c_debug >= 2)
 295                         printk("\n");
 296         }
 297
 298         return num;
 299 err:
 300         dprintk2(2, " ERROR: %i\n", rc);
 301         return rc;
 302 }
 303
 304 /* based on linux/sunrpc/svcauth.h and linux/hash.h
 305  * The original hash function returns a different value, if arch is x86_64
 306  *  or i386.
 307  */
 308 static inline unsigned long em28xx_hash_mem(char *buf, int length, int bits)
 309 {
 310         unsigned long hash = 0;
 311         unsigned long l = 0;
 312         int len = 0;
 313         unsigned char c;
 314         do {
 315                 if (len == length) {
 316                         c = (char)len;
 317                         len = -1;
 318                 } else
 319                         c = *buf++;
 320                 l = (l << 8) | c;
 321                 len++;
 322                 if ((len & (32 / 8 - 1)) == 0)
 323                         hash = ((hash^l) * 0x9e370001UL);
 324         } while (len);
 325
 326         return (hash >> (32 - bits)) & 0xffffffffUL;
 327 }
 328
 329 static int em28xx_i2c_eeprom(struct em28xx *dev, unsigned char *eedata, int len)
 330 {
 331         unsigned char buf, *p = eedata;
 332         struct em28xx_eeprom *em_eeprom = (void *)eedata;
 333         int i, err, size = len, block;
 334
 335         if (dev->chip_id == CHIP_ID_EM2874) {
 336                 /* Empia switched to a 16-bit addressable eeprom in newer
 337                    devices.  While we could certainly write a routine to read
 338                    the eeprom, there is nothing of use in there that cannot be
 339                    accessed through registers, and there is the risk that we
 340                    could corrupt the eeprom (since a 16-bit read call is
 341                    interpreted as a write call by 8-bit eeproms).
 342                 */
 343                 return 0;
 344         }
 345
 346         dev->i2c_client.addr = 0xa0 >> 1;
 347
 348         /* Check if board has eeprom */
 349         err = i2c_master_recv(&dev->i2c_client, &buf, 0);
 350         if (err < 0) {
 351                 em28xx_errdev("board has no eeprom\n");
 352                 memset(eedata, 0, len);
 353                 return -ENODEV;
 354         }
 355
 356         buf = 0;
 357
 358         err = i2c_master_send(&dev->i2c_client, &buf, 1);
 359         if (err != 1) {
 360                 printk(KERN_INFO "%s: Huh, no eeprom present (err=%d)?\n",
 361                        dev->name, err);
 362                 return err;
 363         }
 364         while (size > 0) {
 365                 if (size > 16)
 366                         block = 16;
 367                 else
 368                         block = size;
 369
 370                 if (block !=
 371                     (err = i2c_master_recv(&dev->i2c_client, p, block))) {
 372                         printk(KERN_WARNING
 373                                "%s: i2c eeprom read error (err=%d)\n",
 374                                dev->name, err);
 375                         return err;
 376                 }
 377                 size -= block;
 378                 p += block;
 379         }
 380         for (i = 0; i < len; i++) {
 381                 if (0 == (i % 16))
 382                         printk(KERN_INFO "%s: i2c eeprom %02x:", dev->name, i);
 383                 printk(" %02x", eedata[i]);
 384                 if (15 == (i % 16))
 385                         printk("\n");
 386         }
 387
 388         if (em_eeprom->id == 0x9567eb1a)
 389                 dev->hash = em28xx_hash_mem(eedata, len, 32);
 390
 391         printk(KERN_INFO "EEPROM ID= 0x%08x, hash = 0x%08lx\n",
 392                em_eeprom->id, dev->hash);
 393         printk(KERN_INFO "Vendor/Product ID= %04x:%04x\n", em_eeprom->vendor_ID,
 394                em_eeprom->product_ID);
 395
 396         switch (em_eeprom->chip_conf >> 4 & 0x3) {
 397         case 0:
 398                 printk(KERN_INFO "No audio on board.\n");
 399                 break;
 400         case 1:
 401                 printk(KERN_INFO "AC97 audio (5 sample rates)\n");
 402                 break;
 403         case 2:
 404                 printk(KERN_INFO "I2S audio, sample rate=32k\n");
 405                 break;
 406         case 3:
 407                 printk(KERN_INFO "I2S audio, 3 sample rates\n");
 408                 break;
 409         }
 410
 411         if (em_eeprom->chip_conf & 1 << 3)
 412                 printk(KERN_INFO "USB Remote wakeup capable\n");
 413
 414         if (em_eeprom->chip_conf & 1 << 2)
 415                 printk(KERN_INFO "USB Self power capable\n");
 416
 417         switch (em_eeprom->chip_conf & 0x3) {
 418         case 0:
 419                 printk(KERN_INFO "500mA max power\n");
 420                 break;
 421         case 1:
 422                 printk(KERN_INFO "400mA max power\n");
 423                 break;
 424         case 2:
 425                 printk(KERN_INFO "300mA max power\n");
 426                 break;
 427         case 3:
 428                 printk(KERN_INFO "200mA max power\n");
 429                 break;
 430         }
 431         printk(KERN_INFO "Table at 0x%02x, strings=0x%04x, 0x%04x, 0x%04x\n",
 432                                 em_eeprom->string_idx_table,
 433                                 em_eeprom->string1,
 434                                 em_eeprom->string2,
 435                                 em_eeprom->string3);
 436
 437         return 0;
 438 }
 439
 440 /* ----------------------------------------------------------- */
 441
 442 /*
 443  * functionality()
 444  */
 445 static u32 functionality(struct i2c_adapter *adap)
 446 {
 447         return I2C_FUNC_SMBUS_EMUL;
 448 }
 449
 450 /*
 451  * attach_inform()
 452  * gets called when a device attaches to the i2c bus
 453  * does some basic configuration
 454  */
 455 static int attach_inform(struct i2c_client *client)
 456 {
 457         struct em28xx *dev = client->adapter->algo_data;
 458
 459         switch (client->addr << 1) {
 460         case 0x86:
 461         case 0x84:
 462         case 0x96:
 463         case 0x94:
 464         {
 465                 struct v4l2_priv_tun_config tda9887_cfg;
 466
 467                 struct tuner_setup tun_setup;
 468
 469                 tun_setup.mode_mask = T_ANALOG_TV | T_RADIO;
 470                 tun_setup.type = TUNER_TDA9887;
 471                 tun_setup.addr = client->addr;
 472
 473                 em28xx_i2c_call_clients(dev, TUNER_SET_TYPE_ADDR,
 474                         &tun_setup);
 475
 476                 tda9887_cfg.tuner = TUNER_TDA9887;
 477                 tda9887_cfg.priv = &dev->tda9887_conf;
 478                 em28xx_i2c_call_clients(dev, TUNER_SET_CONFIG,
 479                                         &tda9887_cfg);
 480                 break;
 481         }
 482         case 0x42:
 483                 dprintk1(1, "attach_inform: saa7114 detected.\n");
 484                 break;
 485         case 0x4a:
 486                 dprintk1(1, "attach_inform: saa7113 detected.\n");
 487                 break;
 488         case 0xa0:
 489                 dprintk1(1, "attach_inform: eeprom detected.\n");
 490                 break;
 491         case 0x60:
 492         case 0x8e:
 493         {
 494                 struct IR_i2c *ir = i2c_get_clientdata(client);
 495                 dprintk1(1, "attach_inform: IR detected (%s).\n",
 496                         ir->phys);
 497                 em28xx_set_ir(dev, ir);
 498                 break;
 499         }
 500         case 0x80:
 501         case 0x88:
 502                 dprintk1(1, "attach_inform: msp34xx detected.\n");
 503                 break;
 504         case 0xb8:
 505         case 0xba:
 506                 dprintk1(1, "attach_inform: tvp5150 detected.\n");
 507                 break;
 508
 509         default:
 510                 if (!dev->tuner_addr)
 511                         dev->tuner_addr = client->addr;
 512
 513                 dprintk1(1, "attach inform: detected I2C address %x\n",
 514                                 client->addr << 1);
 515
 516         }
 517
 518         return 0;
 519 }
 520
 521 static struct i2c_algorithm em28xx_algo = {
 522         .master_xfer   = em28xx_i2c_xfer,
 523         .functionality = functionality,
 524 };
 525
 526 static struct i2c_adapter em28xx_adap_template = {
 527         .owner = THIS_MODULE,
 528         .class = I2C_CLASS_TV_ANALOG,
 529         .name = "em28xx",
 530         .id = I2C_HW_B_EM28XX,
 531         .algo = &em28xx_algo,
 532         .client_register = attach_inform,
 533 };
 534
 535 static struct i2c_client em28xx_client_template = {
 536         .name = "em28xx internal",
 537 };
 538
 539 /* ----------------------------------------------------------- */
 540
 541 /*
 542  * i2c_devs
 543  * incomplete list of known devices
 544  */
 545 static char *i2c_devs[128] = {
 546         [0x4a >> 1] = "saa7113h",
 547         [0x60 >> 1] = "remote IR sensor",
 548         [0x8e >> 1] = "remote IR sensor",
 549         [0x86 >> 1] = "tda9887",
 550         [0x80 >> 1] = "msp34xx",
 551         [0x88 >> 1] = "msp34xx",
 552         [0xa0 >> 1] = "eeprom",
 553         [0xb8 >> 1] = "tvp5150a",
 554         [0xba >> 1] = "tvp5150a",
 555         [0xc0 >> 1] = "tuner (analog)",
 556         [0xc2 >> 1] = "tuner (analog)",
 557         [0xc4 >> 1] = "tuner (analog)",
 558         [0xc6 >> 1] = "tuner (analog)",
 559 };
 560
 561 /*
 562  * do_i2c_scan()
 563  * check i2c address range for devices
 564  */
 565 void em28xx_do_i2c_scan(struct em28xx *dev)
 566 {
 567         u8 i2c_devicelist[128];
 568         unsigned char buf;
 569         int i, rc;
 570
 571         memset(i2c_devicelist, 0, ARRAY_SIZE(i2c_devicelist));
 572
 573         for (i = 0; i < ARRAY_SIZE(i2c_devs); i++) {
 574                 dev->i2c_client.addr = i;
 575                 rc = i2c_master_recv(&dev->i2c_client, &buf, 0);
 576                 if (rc < 0)
 577                         continue;
 578                 i2c_devicelist[i] = i;
 579                 printk(KERN_INFO "%s: found i2c device @ 0x%x [%s]\n",
 580                        dev->name, i << 1, i2c_devs[i] ? i2c_devs[i] : "???");
 581         }
 582
 583         dev->i2c_hash = em28xx_hash_mem(i2c_devicelist,
 584                                         ARRAY_SIZE(i2c_devicelist), 32);
 585 }
 586
 587 /*
 588  * em28xx_i2c_call_clients()
 589  * send commands to all attached i2c devices
 590  */
 591 void em28xx_i2c_call_clients(struct em28xx *dev, unsigned int cmd, void *arg)
 592 {
 593         BUG_ON(NULL == dev->i2c_adap.algo_data);
 594         i2c_clients_command(&dev->i2c_adap, cmd, arg);
 595 }
 596
 597 /*
 598  * em28xx_i2c_register()
 599  * register i2c bus
 600  */
 601 int em28xx_i2c_register(struct em28xx *dev)
 602 {
 603         int retval;
 604
 605         BUG_ON(!dev->em28xx_write_regs || !dev->em28xx_read_reg);
 606         BUG_ON(!dev->em28xx_write_regs_req || !dev->em28xx_read_reg_req);
 607         dev->i2c_adap = em28xx_adap_template;
 608         dev->i2c_adap.dev.parent = &dev->udev->dev;
 609         strcpy(dev->i2c_adap.name, dev->name);
 610         dev->i2c_adap.algo_data = dev;
 611
 612         retval = i2c_add_adapter(&dev->i2c_adap);
 613         if (retval < 0) {
 614                 em28xx_errdev("%s: i2c_add_adapter failed! retval [%d]\n",
 615                         __func__, retval);
 616                 return retval;
 617         }
 618
 619         dev->i2c_client = em28xx_client_template;
 620         dev->i2c_client.adapter = &dev->i2c_adap;
 621
 622         retval = em28xx_i2c_eeprom(dev, dev->eedata, sizeof(dev->eedata));
 623         if ((retval < 0) && (retval != -ENODEV)) {
 624                 em28xx_errdev("%s: em28xx_i2_eeprom failed! retval [%d]\n",
 625                         __func__, retval);
 626
 627                 return retval;
 628         }
 629
 630         if (i2c_scan)
 631                 em28xx_do_i2c_scan(dev);
 632
 633         return 0;
 634 }
 635
 636 /*
 637  * em28xx_i2c_unregister()
 638  * unregister i2c_bus
 639  */
 640 int em28xx_i2c_unregister(struct em28xx *dev)
 641 {
 642         i2c_del_adapter(&dev->i2c_adap);
 643         return 0;
 644 }