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

   1 /*
   2  * usbvision_i2c.c
   3  *  i2c algorithm for USB-I2C Bridges
   4  *
   5  * Copyright (c) 1999-2007 Joerg Heckenbach <joerg@heckenbach-aw.de>
   6  *                         Dwaine Garden <dwainegarden@rogers.com>
   7  *
   8  * This module is part of usbvision driver project.
   9  * Updates to driver completed by Dwaine P. Garden
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation; either version 2 of the License, or
  14  * (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program; if not, write to the Free Software
  23  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  24  */
  25
  26
  27 #include <linux/kernel.h>
  28 #include <linux/module.h>
  29 #include <linux/delay.h>
  30 #include <linux/slab.h>
  31 #include <linux/version.h>
  32 #include <linux/utsname.h>
  33 #include <linux/init.h>
  34 #include <asm/uaccess.h>
  35 #include <linux/ioport.h>
  36 #include <linux/errno.h>
  37 #include <linux/usb.h>
  38 #include <linux/i2c.h>
  39 #include "usbvision.h"
  40
  41 #define DBG_I2C         1<<0
  42
  43 static int i2c_debug = 0;
  44
  45 module_param (i2c_debug, int, 0644);                    // debug_i2c_usb mode of the device driver
  46 MODULE_PARM_DESC(i2c_debug, "enable debug messages [i2c]");
  47
  48 #define PDEBUG(level, fmt, args...) \
  49                 if (i2c_debug & (level)) info("[%s:%d] " fmt, __PRETTY_FUNCTION__, __LINE__ , ## args)
  50
  51 static int usbvision_i2c_write(struct usb_usbvision *usbvision, unsigned char addr, char *buf,
  52                             short len);
  53 static int usbvision_i2c_read(struct usb_usbvision *usbvision, unsigned char addr, char *buf,
  54                            short len);
  55
  56 static inline int try_write_address(struct i2c_adapter *i2c_adap,
  57                                     unsigned char addr, int retries)
  58 {
  59         struct usb_usbvision *usbvision;
  60         int i, ret = -1;
  61         char buf[4];
  62
  63         usbvision = (struct usb_usbvision *)i2c_get_adapdata(i2c_adap);
  64         buf[0] = 0x00;
  65         for (i = 0; i <= retries; i++) {
  66                 ret = (usbvision_i2c_write(usbvision, addr, buf, 1));
  67                 if (ret == 1)
  68                         break;  /* success! */
  69                 udelay(5);
  70                 if (i == retries)       /* no success */
  71                         break;
  72                 udelay(10);
  73         }
  74         if (i) {
  75                 PDEBUG(DBG_I2C,"Needed %d retries for address %#2x", i, addr);
  76                 PDEBUG(DBG_I2C,"Maybe there's no device at this address");
  77         }
  78         return ret;
  79 }
  80
  81 static inline int try_read_address(struct i2c_adapter *i2c_adap,
  82                                    unsigned char addr, int retries)
  83 {
  84         struct usb_usbvision *usbvision;
  85         int i, ret = -1;
  86         char buf[4];
  87
  88         usbvision = (struct usb_usbvision *)i2c_get_adapdata(i2c_adap);
  89         for (i = 0; i <= retries; i++) {
  90                 ret = (usbvision_i2c_read(usbvision, addr, buf, 1));
  91                 if (ret == 1)
  92                         break;  /* success! */
  93                 udelay(5);
  94                 if (i == retries)       /* no success */
  95                         break;
  96                 udelay(10);
  97         }
  98         if (i) {
  99                 PDEBUG(DBG_I2C,"Needed %d retries for address %#2x", i, addr);
 100                 PDEBUG(DBG_I2C,"Maybe there's no device at this address");
 101         }
 102         return ret;
 103 }
 104
 105 static inline int usb_find_address(struct i2c_adapter *i2c_adap,
 106                                    struct i2c_msg *msg, int retries,
 107                                    unsigned char *add)
 108 {
 109         unsigned short flags = msg->flags;
 110
 111         unsigned char addr;
 112         int ret;
 113         if ((flags & I2C_M_TEN)) {
 114                 /* a ten bit address */
 115                 addr = 0xf0 | ((msg->addr >> 7) & 0x03);
 116                 /* try extended address code... */
 117                 ret = try_write_address(i2c_adap, addr, retries);
 118                 if (ret != 1) {
 119                         err("died at extended address code, while writing");
 120                         return -EREMOTEIO;
 121                 }
 122                 add[0] = addr;
 123                 if (flags & I2C_M_RD) {
 124                         /* okay, now switch into reading mode */
 125                         addr |= 0x01;
 126                         ret = try_read_address(i2c_adap, addr, retries);
 127                         if (ret != 1) {
 128                                 err("died at extended address code, while reading");
 129                                 return -EREMOTEIO;
 130                         }
 131                 }
 132
 133         } else {                /* normal 7bit address  */
 134                 addr = (msg->addr << 1);
 135                 if (flags & I2C_M_RD)
 136                         addr |= 1;
 137
 138                 add[0] = addr;
 139                 if (flags & I2C_M_RD)
 140                         ret = try_read_address(i2c_adap, addr, retries);
 141                 else
 142                         ret = try_write_address(i2c_adap, addr, retries);
 143
 144                 if (ret != 1) {
 145                         return -EREMOTEIO;
 146                 }
 147         }
 148         return 0;
 149 }
 150
 151 static int
 152 usbvision_i2c_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg msgs[], int num)
 153 {
 154         struct i2c_msg *pmsg;
 155         struct usb_usbvision *usbvision;
 156         int i, ret;
 157         unsigned char addr;
 158
 159         usbvision = (struct usb_usbvision *)i2c_get_adapdata(i2c_adap);
 160
 161         for (i = 0; i < num; i++) {
 162                 pmsg = &msgs[i];
 163                 ret = usb_find_address(i2c_adap, pmsg, i2c_adap->retries, &addr);
 164                 if (ret != 0) {
 165                         PDEBUG(DBG_I2C,"got NAK from device, message #%d", i);
 166                         return (ret < 0) ? ret : -EREMOTEIO;
 167                 }
 168
 169                 if (pmsg->flags & I2C_M_RD) {
 170                         /* read bytes into buffer */
 171                         ret = (usbvision_i2c_read(usbvision, addr, pmsg->buf, pmsg->len));
 172                         if (ret < pmsg->len) {
 173                                 return (ret < 0) ? ret : -EREMOTEIO;
 174                         }
 175                 } else {
 176                         /* write bytes from buffer */
 177                         ret = (usbvision_i2c_write(usbvision, addr, pmsg->buf, pmsg->len));
 178                         if (ret < pmsg->len) {
 179                                 return (ret < 0) ? ret : -EREMOTEIO;
 180                         }
 181                 }
 182         }
 183         return num;
 184 }
 185
 186 static u32 functionality(struct i2c_adapter *adap)
 187 {
 188         return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR;
 189 }
 190
 191
 192 /* -----exported algorithm data: -------------------------------------  */
 193
 194 static struct i2c_algorithm usbvision_algo = {
 195         .master_xfer   = usbvision_i2c_xfer,
 196         .smbus_xfer    = NULL,
 197         .functionality = functionality,
 198 };
 199
 200
 201 /*
 202  * registering functions to load algorithms at runtime
 203  */
 204 static int usbvision_i2c_usb_add_bus(struct i2c_adapter *adap)
 205 {
 206         PDEBUG(DBG_I2C, "I2C   debugging is enabled [i2c]");
 207         PDEBUG(DBG_I2C, "ALGO   debugging is enabled [i2c]");
 208
 209         /* register new adapter to i2c module... */
 210
 211         adap->algo = &usbvision_algo;
 212
 213         adap->timeout = 100;    /* default values, should       */
 214         adap->retries = 3;      /* be replaced by defines       */
 215
 216         i2c_add_adapter(adap);
 217
 218         PDEBUG(DBG_I2C,"i2c bus for %s registered", adap->name);
 219
 220         return 0;
 221 }
 222
 223 /* ----------------------------------------------------------------------- */
 224 /* usbvision specific I2C functions                                        */
 225 /* ----------------------------------------------------------------------- */
 226 static struct i2c_adapter i2c_adap_template;
 227 static struct i2c_client i2c_client_template;
 228
 229 int usbvision_i2c_register(struct usb_usbvision *usbvision)
 230 {
 231         memcpy(&usbvision->i2c_adap, &i2c_adap_template,
 232                sizeof(struct i2c_adapter));
 233         memcpy(&usbvision->i2c_client, &i2c_client_template,
 234                sizeof(struct i2c_client));
 235
 236         sprintf(usbvision->i2c_adap.name + strlen(usbvision->i2c_adap.name),
 237                 " #%d", usbvision->vdev->minor & 0x1f);
 238         PDEBUG(DBG_I2C,"Adaptername: %s", usbvision->i2c_adap.name);
 239         usbvision->i2c_adap.dev.parent = &usbvision->dev->dev;
 240
 241         i2c_set_adapdata(&usbvision->i2c_adap, usbvision);
 242         i2c_set_clientdata(&usbvision->i2c_client, usbvision);
 243
 244         usbvision->i2c_client.adapter = &usbvision->i2c_adap;
 245
 246         if (usbvision_write_reg(usbvision, USBVISION_SER_MODE, USBVISION_IIC_LRNACK) < 0) {
 247                 printk(KERN_ERR "usbvision_register: can't write reg\n");
 248                 return -EBUSY;
 249         }
 250
 251 #ifdef CONFIG_MODULES
 252         /* Request the load of the i2c modules we need */
 253         switch (usbvision_device_data[usbvision->DevModel].Codec) {
 254         case CODEC_SAA7113:
 255                 request_module("saa7115");
 256                 break;
 257         case CODEC_SAA7111:
 258                 request_module("saa7115");
 259                 break;
 260         }
 261         if (usbvision_device_data[usbvision->DevModel].Tuner == 1) {
 262                 request_module("tuner");
 263         }
 264 #endif
 265
 266         return usbvision_i2c_usb_add_bus(&usbvision->i2c_adap);
 267 }
 268
 269 int usbvision_i2c_unregister(struct usb_usbvision *usbvision)
 270 {
 271
 272         i2c_del_adapter(&(usbvision->i2c_adap));
 273
 274         PDEBUG(DBG_I2C,"i2c bus for %s unregistered", usbvision->i2c_adap.name);
 275
 276         return 0;
 277 }
 278
 279 void call_i2c_clients(struct usb_usbvision *usbvision, unsigned int cmd,
 280                       void *arg)
 281 {
 282         i2c_clients_command(&usbvision->i2c_adap, cmd, arg);
 283 }
 284
 285 static int attach_inform(struct i2c_client *client)
 286 {
 287         struct usb_usbvision *usbvision;
 288
 289         usbvision = (struct usb_usbvision *)i2c_get_adapdata(client->adapter);
 290
 291         switch (client->addr << 1) {
 292                 case 0x42 << 1:
 293                 case 0x43 << 1:
 294                 case 0x4a << 1:
 295                 case 0x4b << 1:
 296                         PDEBUG(DBG_I2C,"attach_inform: tda9887 detected.");
 297                         break;
 298                 case 0x42:
 299                         PDEBUG(DBG_I2C,"attach_inform: saa7114 detected.");
 300                         break;
 301                 case 0x4a:
 302                         PDEBUG(DBG_I2C,"attach_inform: saa7113 detected.");
 303                         break;
 304                 case 0x48:
 305                         PDEBUG(DBG_I2C,"attach_inform: saa7111 detected.");
 306                         break;
 307                 case 0xa0:
 308                         PDEBUG(DBG_I2C,"attach_inform: eeprom detected.");
 309                         break;
 310
 311                 default:
 312                         {
 313                                 struct tuner_setup tun_setup;
 314
 315                                 PDEBUG(DBG_I2C,"attach inform: detected I2C address %x", client->addr << 1);
 316                                 usbvision->tuner_addr = client->addr;
 317
 318                                 if ((usbvision->have_tuner) && (usbvision->tuner_type != -1)) {
 319                                         tun_setup.mode_mask = T_ANALOG_TV | T_RADIO;
 320                                         tun_setup.type = usbvision->tuner_type;
 321                                         tun_setup.addr = usbvision->tuner_addr;
 322                                         call_i2c_clients(usbvision, TUNER_SET_TYPE_ADDR, &tun_setup);
 323                                 }
 324                         }
 325                         break;
 326         }
 327         return 0;
 328 }
 329
 330 static int detach_inform(struct i2c_client *client)
 331 {
 332         struct usb_usbvision *usbvision;
 333
 334         usbvision = (struct usb_usbvision *)i2c_get_adapdata(client->adapter);
 335
 336         PDEBUG(DBG_I2C,"usbvision[%d] detaches %s", usbvision->nr, client->name);
 337         return 0;
 338 }
 339
 340 static int
 341 usbvision_i2c_read_max4(struct usb_usbvision *usbvision, unsigned char addr,
 342                      char *buf, short len)
 343 {
 344         int rc, retries;
 345
 346         for (retries = 5;;) {
 347                 rc = usbvision_write_reg(usbvision, USBVISION_SER_ADRS, addr);
 348                 if (rc < 0)
 349                         return rc;
 350
 351                 /* Initiate byte read cycle                    */
 352                 /* USBVISION_SER_CONT <- d0-d2 n. of bytes to r/w */
 353                 /*                    d3 0=Wr 1=Rd             */
 354                 rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT,
 355                                       (len & 0x07) | 0x18);
 356                 if (rc < 0)
 357                         return rc;
 358
 359                 /* Test for Busy and ACK */
 360                 do {
 361                         /* USBVISION_SER_CONT -> d4 == 0 busy */
 362                         rc = usbvision_read_reg(usbvision, USBVISION_SER_CONT);
 363                 } while (rc > 0 && ((rc & 0x10) != 0)); /* Retry while busy */
 364                 if (rc < 0)
 365                         return rc;
 366
 367                 /* USBVISION_SER_CONT -> d5 == 1 Not ack */
 368                 if ((rc & 0x20) == 0)   /* Ack? */
 369                         break;
 370
 371                 /* I2C abort */
 372                 rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT, 0x00);
 373                 if (rc < 0)
 374                         return rc;
 375
 376                 if (--retries < 0)
 377                         return -1;
 378         }
 379
 380         switch (len) {
 381         case 4:
 382                 buf[3] = usbvision_read_reg(usbvision, USBVISION_SER_DAT4);
 383         case 3:
 384                 buf[2] = usbvision_read_reg(usbvision, USBVISION_SER_DAT3);
 385         case 2:
 386                 buf[1] = usbvision_read_reg(usbvision, USBVISION_SER_DAT2);
 387         case 1:
 388                 buf[0] = usbvision_read_reg(usbvision, USBVISION_SER_DAT1);
 389                 break;
 390         default:
 391                 printk(KERN_ERR
 392                        "usbvision_i2c_read_max4: buffer length > 4\n");
 393         }
 394
 395         if (i2c_debug & DBG_I2C) {
 396                 int idx;
 397                 for (idx = 0; idx < len; idx++) {
 398                         PDEBUG(DBG_I2C,"read %x from address %x", (unsigned char)buf[idx], addr);
 399                 }
 400         }
 401         return len;
 402 }
 403
 404
 405 static int usbvision_i2c_write_max4(struct usb_usbvision *usbvision,
 406                                  unsigned char addr, const char *buf,
 407                                  short len)
 408 {
 409         int rc, retries;
 410         int i;
 411         unsigned char value[6];
 412         unsigned char ser_cont;
 413
 414         ser_cont = (len & 0x07) | 0x10;
 415
 416         value[0] = addr;
 417         value[1] = ser_cont;
 418         for (i = 0; i < len; i++)
 419                 value[i + 2] = buf[i];
 420
 421         for (retries = 5;;) {
 422                 rc = usb_control_msg(usbvision->dev,
 423                                      usb_sndctrlpipe(usbvision->dev, 1),
 424                                      USBVISION_OP_CODE,
 425                                      USB_DIR_OUT | USB_TYPE_VENDOR |
 426                                      USB_RECIP_ENDPOINT, 0,
 427                                      (__u16) USBVISION_SER_ADRS, value,
 428                                      len + 2, HZ);
 429
 430                 if (rc < 0)
 431                         return rc;
 432
 433                 rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT,
 434                                       (len & 0x07) | 0x10);
 435                 if (rc < 0)
 436                         return rc;
 437
 438                 /* Test for Busy and ACK */
 439                 do {
 440                         rc = usbvision_read_reg(usbvision, USBVISION_SER_CONT);
 441                 } while (rc > 0 && ((rc & 0x10) != 0)); /* Retry while busy */
 442                 if (rc < 0)
 443                         return rc;
 444
 445                 if ((rc & 0x20) == 0)   /* Ack? */
 446                         break;
 447
 448                 /* I2C abort */
 449                 usbvision_write_reg(usbvision, USBVISION_SER_CONT, 0x00);
 450
 451                 if (--retries < 0)
 452                         return -1;
 453
 454         }
 455
 456         if (i2c_debug & DBG_I2C) {
 457                 int idx;
 458                 for (idx = 0; idx < len; idx++) {
 459                         PDEBUG(DBG_I2C,"wrote %x at address %x", (unsigned char)buf[idx], addr);
 460                 }
 461         }
 462         return len;
 463 }
 464
 465 static int usbvision_i2c_write(struct usb_usbvision *usbvision, unsigned char addr, char *buf,
 466                             short len)
 467 {
 468         char *bufPtr = buf;
 469         int retval;
 470         int wrcount = 0;
 471         int count;
 472         int maxLen = 4;
 473
 474         while (len > 0) {
 475                 count = (len > maxLen) ? maxLen : len;
 476                 retval = usbvision_i2c_write_max4(usbvision, addr, bufPtr, count);
 477                 if (retval > 0) {
 478                         len -= count;
 479                         bufPtr += count;
 480                         wrcount += count;
 481                 } else
 482                         return (retval < 0) ? retval : -EFAULT;
 483         }
 484         return wrcount;
 485 }
 486
 487 static int usbvision_i2c_read(struct usb_usbvision *usbvision, unsigned char addr, char *buf,
 488                            short len)
 489 {
 490         char temp[4];
 491         int retval, i;
 492         int rdcount = 0;
 493         int count;
 494
 495         while (len > 0) {
 496                 count = (len > 3) ? 4 : len;
 497                 retval = usbvision_i2c_read_max4(usbvision, addr, temp, count);
 498                 if (retval > 0) {
 499                         for (i = 0; i < len; i++)
 500                                 buf[rdcount + i] = temp[i];
 501                         len -= count;
 502                         rdcount += count;
 503                 } else
 504                         return (retval < 0) ? retval : -EFAULT;
 505         }
 506         return rdcount;
 507 }
 508
 509 static struct i2c_adapter i2c_adap_template = {
 510         .owner = THIS_MODULE,
 511         .name              = "usbvision",
 512         .id                = I2C_HW_B_BT848, /* FIXME */
 513         .client_register   = attach_inform,
 514         .client_unregister = detach_inform,
 515 #ifdef I2C_ADAP_CLASS_TV_ANALOG
 516         .class             = I2C_ADAP_CLASS_TV_ANALOG,
 517 #else
 518         .class             = I2C_CLASS_TV_ANALOG,
 519 #endif
 520 };
 521
 522 static struct i2c_client i2c_client_template = {
 523         .name           = "usbvision internal",
 524 };
 525
 526 /*
 527  * Overrides for Emacs so that we follow Linus's tabbing style.
 528  * ---------------------------------------------------------------------------
 529  * Local variables:
 530  * c-basic-offset: 8
 531  * End:
 532  */