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

   1 /*
   2  * I2C_ALGO_USB.C
   3  *  i2c algorithm for USB-I2C Bridges
   4  *
   5  * Copyright (c) 1999-2005 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/sched.h>
  38 #include <linux/usb.h>
  39 #include <linux/i2c.h>
  40 #include "usbvision.h"
  41
  42 #define DBG_I2C         1<<0
  43 #define DBG_ALGO        1<<1
  44
  45 static int i2c_debug = 0;
  46
  47 module_param (i2c_debug, int, 0644);                    // debug_i2c_usb mode of the device driver
  48 MODULE_PARM_DESC(i2c_debug, "enable debug messages [i2c]");
  49
  50 #define PDEBUG(level, fmt, args...) \
  51                 if (i2c_debug & (level)) info("[%s:%d] " fmt, __PRETTY_FUNCTION__, __LINE__ , ## args)
  52
  53 static int usbvision_i2c_write(void *data, unsigned char addr, char *buf,
  54                             short len);
  55 static int usbvision_i2c_read(void *data, unsigned char addr, char *buf,
  56                            short len);
  57
  58 static inline int try_write_address(struct i2c_adapter *i2c_adap,
  59                                     unsigned char addr, int retries)
  60 {
  61         struct i2c_algo_usb_data *adap = i2c_adap->algo_data;
  62         void *data;
  63         int i, ret = -1;
  64         char buf[4];
  65
  66         data = i2c_get_adapdata(i2c_adap);
  67         buf[0] = 0x00;
  68         for (i = 0; i <= retries; i++) {
  69                 ret = (usbvision_i2c_write(data, addr, buf, 1));
  70                 if (ret == 1)
  71                         break;  /* success! */
  72                 udelay(5 /*adap->udelay */ );
  73                 if (i == retries)       /* no success */
  74                         break;
  75                 udelay(adap->udelay);
  76         }
  77         if (i) {
  78                 PDEBUG(DBG_ALGO,"Needed %d retries for address %#2x", i, addr);
  79                 PDEBUG(DBG_ALGO,"Maybe there's no device at this address");
  80         }
  81         return ret;
  82 }
  83
  84 static inline int try_read_address(struct i2c_adapter *i2c_adap,
  85                                    unsigned char addr, int retries)
  86 {
  87         struct i2c_algo_usb_data *adap = i2c_adap->algo_data;
  88         void *data;
  89         int i, ret = -1;
  90         char buf[4];
  91
  92         data = i2c_get_adapdata(i2c_adap);
  93         for (i = 0; i <= retries; i++) {
  94                 ret = (usbvision_i2c_read(data, addr, buf, 1));
  95                 if (ret == 1)
  96                         break;  /* success! */
  97                 udelay(5 /*adap->udelay */ );
  98                 if (i == retries)       /* no success */
  99                         break;
 100                 udelay(adap->udelay);
 101         }
 102         if (i) {
 103                 PDEBUG(DBG_ALGO,"Needed %d retries for address %#2x", i, addr);
 104                 PDEBUG(DBG_ALGO,"Maybe there's no device at this address");
 105         }
 106         return ret;
 107 }
 108
 109 static inline int usb_find_address(struct i2c_adapter *i2c_adap,
 110                                    struct i2c_msg *msg, int retries,
 111                                    unsigned char *add)
 112 {
 113         unsigned short flags = msg->flags;
 114
 115         unsigned char addr;
 116         int ret;
 117         if ((flags & I2C_M_TEN)) {
 118                 /* a ten bit address */
 119                 addr = 0xf0 | ((msg->addr >> 7) & 0x03);
 120                 /* try extended address code... */
 121                 ret = try_write_address(i2c_adap, addr, retries);
 122                 if (ret != 1) {
 123                         err("died at extended address code, while writing");
 124                         return -EREMOTEIO;
 125                 }
 126                 add[0] = addr;
 127                 if (flags & I2C_M_RD) {
 128                         /* okay, now switch into reading mode */
 129                         addr |= 0x01;
 130                         ret = try_read_address(i2c_adap, addr, retries);
 131                         if (ret != 1) {
 132                                 err("died at extended address code, while reading");
 133                                 return -EREMOTEIO;
 134                         }
 135                 }
 136
 137         } else {                /* normal 7bit address  */
 138                 addr = (msg->addr << 1);
 139                 if (flags & I2C_M_RD)
 140                         addr |= 1;
 141                 if (flags & I2C_M_REV_DIR_ADDR)
 142                         addr ^= 1;
 143
 144                 add[0] = addr;
 145                 if (flags & I2C_M_RD)
 146                         ret = try_read_address(i2c_adap, addr, retries);
 147                 else
 148                         ret = try_write_address(i2c_adap, addr, retries);
 149
 150                 if (ret != 1) {
 151                         return -EREMOTEIO;
 152                 }
 153         }
 154         return 0;
 155 }
 156
 157 static int
 158 usb_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg msgs[], int num)
 159 {
 160         struct i2c_msg *pmsg;
 161         void *data;
 162         int i, ret;
 163         unsigned char addr;
 164
 165         data = i2c_get_adapdata(i2c_adap);
 166
 167         for (i = 0; i < num; i++) {
 168                 pmsg = &msgs[i];
 169                 ret = usb_find_address(i2c_adap, pmsg, i2c_adap->retries, &addr);
 170                 if (ret != 0) {
 171                         PDEBUG(DBG_ALGO,"got NAK from device, message #%d", i);
 172                         return (ret < 0) ? ret : -EREMOTEIO;
 173                 }
 174
 175                 if (pmsg->flags & I2C_M_RD) {
 176                         /* read bytes into buffer */
 177                         ret = (usbvision_i2c_read(data, addr, pmsg->buf, pmsg->len));
 178                         if (ret < pmsg->len) {
 179                                 return (ret < 0) ? ret : -EREMOTEIO;
 180                         }
 181                 } else {
 182                         /* write bytes from buffer */
 183                         ret = (usbvision_i2c_write(data, addr, pmsg->buf, pmsg->len));
 184                         if (ret < pmsg->len) {
 185                                 return (ret < 0) ? ret : -EREMOTEIO;
 186                         }
 187                 }
 188         }
 189         return num;
 190 }
 191
 192 static int algo_control(struct i2c_adapter *adapter, unsigned int cmd, unsigned long arg)
 193 {
 194         return 0;
 195 }
 196
 197 static u32 usb_func(struct i2c_adapter *adap)
 198 {
 199         return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR | I2C_FUNC_PROTOCOL_MANGLING;
 200 }
 201
 202
 203 /* -----exported algorithm data: -------------------------------------  */
 204
 205 static struct i2c_algorithm i2c_usb_algo = {
 206         .master_xfer   = usb_xfer,
 207         .smbus_xfer    = NULL,
 208         .algo_control  = algo_control,
 209         .functionality = usb_func,
 210 };
 211
 212
 213 /*
 214  * registering functions to load algorithms at runtime
 215  */
 216 int usbvision_i2c_usb_add_bus(struct i2c_adapter *adap)
 217 {
 218         PDEBUG(DBG_I2C, "I2C   debugging is enabled [i2c]");
 219         PDEBUG(DBG_ALGO, "ALGO   debugging is enabled [i2c]");
 220
 221         /* register new adapter to i2c module... */
 222
 223         adap->algo = &i2c_usb_algo;
 224
 225         adap->timeout = 100;    /* default values, should       */
 226         adap->retries = 3;      /* be replaced by defines       */
 227
 228         i2c_add_adapter(adap);
 229
 230         PDEBUG(DBG_ALGO,"i2c bus for %s registered", adap->name);
 231
 232         return 0;
 233 }
 234
 235
 236 int usbvision_i2c_usb_del_bus(struct i2c_adapter *adap)
 237 {
 238
 239         i2c_del_adapter(adap);
 240
 241         PDEBUG(DBG_ALGO,"i2c bus for %s unregistered", adap->name);
 242
 243         return 0;
 244 }
 245
 246
 247 /* ----------------------------------------------------------------------- */
 248 /* usbvision specific I2C functions                                        */
 249 /* ----------------------------------------------------------------------- */
 250 static struct i2c_adapter i2c_adap_template;
 251 static struct i2c_algo_usb_data i2c_algo_template;
 252 static struct i2c_client i2c_client_template;
 253
 254 int usbvision_init_i2c(struct usb_usbvision *usbvision)
 255 {
 256         memcpy(&usbvision->i2c_adap, &i2c_adap_template,
 257                sizeof(struct i2c_adapter));
 258         memcpy(&usbvision->i2c_algo, &i2c_algo_template,
 259                sizeof(struct i2c_algo_usb_data));
 260         memcpy(&usbvision->i2c_client, &i2c_client_template,
 261                sizeof(struct i2c_client));
 262
 263         sprintf(usbvision->i2c_adap.name + strlen(usbvision->i2c_adap.name),
 264                 " #%d", usbvision->vdev->minor & 0x1f);
 265         PDEBUG(DBG_I2C,"Adaptername: %s", usbvision->i2c_adap.name);
 266
 267         i2c_set_adapdata(&usbvision->i2c_adap, usbvision);
 268         i2c_set_clientdata(&usbvision->i2c_client, usbvision);
 269         i2c_set_algo_usb_data(&usbvision->i2c_algo, usbvision);
 270
 271         usbvision->i2c_adap.algo_data = &usbvision->i2c_algo;
 272         usbvision->i2c_client.adapter = &usbvision->i2c_adap;
 273
 274         if (usbvision_write_reg(usbvision, USBVISION_SER_MODE, USBVISION_IIC_LRNACK) < 0) {
 275                 printk(KERN_ERR "usbvision_init_i2c: can't write reg\n");
 276                 return -EBUSY;
 277         }
 278
 279 #ifdef CONFIG_MODULES
 280         /* Request the load of the i2c modules we need */
 281         switch (usbvision_device_data[usbvision->DevModel].Codec) {
 282         case CODEC_SAA7113:
 283                 request_module("saa7115");
 284                 break;
 285         case CODEC_SAA7111:
 286                 request_module("saa7115");
 287                 break;
 288         }
 289         if (usbvision_device_data[usbvision->DevModel].Tuner == 1) {
 290                 request_module("tuner");
 291         }
 292 #endif
 293
 294         return usbvision_i2c_usb_add_bus(&usbvision->i2c_adap);
 295 }
 296
 297 void call_i2c_clients(struct usb_usbvision *usbvision, unsigned int cmd,
 298                       void *arg)
 299 {
 300         BUG_ON(NULL == usbvision->i2c_adap.algo_data);
 301         i2c_clients_command(&usbvision->i2c_adap, cmd, arg);
 302 }
 303
 304 static int attach_inform(struct i2c_client *client)
 305 {
 306         struct usb_usbvision *usbvision;
 307
 308         usbvision = (struct usb_usbvision *)i2c_get_adapdata(client->adapter);
 309
 310         switch (client->addr << 1) {
 311                 case 0x43:
 312                 case 0x4b:
 313                 {
 314                         struct tuner_setup tun_setup;
 315
 316                         tun_setup.mode_mask = T_ANALOG_TV | T_RADIO;
 317                         tun_setup.type = TUNER_TDA9887;
 318                         tun_setup.addr = client->addr;
 319
 320                         call_i2c_clients(usbvision, TUNER_SET_TYPE_ADDR, &tun_setup);
 321
 322                         break;
 323                 }
 324                 case 0x42:
 325                         PDEBUG(DBG_I2C,"attach_inform: saa7114 detected.");
 326                         break;
 327                 case 0x4a:
 328                         PDEBUG(DBG_I2C,"attach_inform: saa7113 detected.");
 329                         break;
 330                 case 0xa0:
 331                         PDEBUG(DBG_I2C,"attach_inform: eeprom detected.");
 332                         break;
 333
 334                 default:
 335                         {
 336                                 struct tuner_setup tun_setup;
 337
 338                                 PDEBUG(DBG_I2C,"attach inform: detected I2C address %x", client->addr << 1);
 339                                 usbvision->tuner_addr = client->addr;
 340
 341                                 if ((usbvision->have_tuner) && (usbvision->tuner_type != -1)) {
 342                                         tun_setup.mode_mask = T_ANALOG_TV | T_RADIO;
 343                                         tun_setup.type = usbvision->tuner_type;
 344                                         tun_setup.addr = usbvision->tuner_addr;
 345                                         call_i2c_clients(usbvision, TUNER_SET_TYPE_ADDR, &tun_setup);
 346                                 }
 347                         }
 348                         break;
 349         }
 350         return 0;
 351 }
 352
 353 static int detach_inform(struct i2c_client *client)
 354 {
 355         struct usb_usbvision *usbvision;
 356
 357         usbvision = (struct usb_usbvision *)i2c_get_adapdata(client->adapter);
 358
 359         PDEBUG(DBG_I2C,"usbvision[%d] detaches %s", usbvision->nr, client->name);
 360         return 0;
 361 }
 362
 363 static int
 364 usbvision_i2c_read_max4(struct usb_usbvision *usbvision, unsigned char addr,
 365                      char *buf, short len)
 366 {
 367         int rc, retries;
 368
 369         for (retries = 5;;) {
 370                 rc = usbvision_write_reg(usbvision, USBVISION_SER_ADRS, addr);
 371                 if (rc < 0)
 372                         return rc;
 373
 374                 /* Initiate byte read cycle                    */
 375                 /* USBVISION_SER_CONT <- d0-d2 n. of bytes to r/w */
 376                 /*                    d3 0=Wr 1=Rd             */
 377                 rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT,
 378                                       (len & 0x07) | 0x18);
 379                 if (rc < 0)
 380                         return rc;
 381
 382                 /* Test for Busy and ACK */
 383                 do {
 384                         /* USBVISION_SER_CONT -> d4 == 0 busy */
 385                         rc = usbvision_read_reg(usbvision, USBVISION_SER_CONT);
 386                 } while (rc > 0 && ((rc & 0x10) != 0)); /* Retry while busy */
 387                 if (rc < 0)
 388                         return rc;
 389
 390                 /* USBVISION_SER_CONT -> d5 == 1 Not ack */
 391                 if ((rc & 0x20) == 0)   /* Ack? */
 392                         break;
 393
 394                 /* I2C abort */
 395                 rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT, 0x00);
 396                 if (rc < 0)
 397                         return rc;
 398
 399                 if (--retries < 0)
 400                         return -1;
 401         }
 402
 403         switch (len) {
 404         case 4:
 405                 buf[3] = usbvision_read_reg(usbvision, USBVISION_SER_DAT4);
 406         case 3:
 407                 buf[2] = usbvision_read_reg(usbvision, USBVISION_SER_DAT3);
 408         case 2:
 409                 buf[1] = usbvision_read_reg(usbvision, USBVISION_SER_DAT2);
 410         case 1:
 411                 buf[0] = usbvision_read_reg(usbvision, USBVISION_SER_DAT1);
 412                 break;
 413         default:
 414                 printk(KERN_ERR
 415                        "usbvision_i2c_read_max4: buffer length > 4\n");
 416         }
 417
 418         if (i2c_debug & DBG_I2C) {
 419                 int idx;
 420                 for (idx = 0; idx < len; idx++) {
 421                         PDEBUG(DBG_I2C,"read %x from address %x", (unsigned char)buf[idx], addr);
 422                 }
 423         }
 424         return len;
 425 }
 426
 427
 428 static int usbvision_i2c_write_max4(struct usb_usbvision *usbvision,
 429                                  unsigned char addr, const char *buf,
 430                                  short len)
 431 {
 432         int rc, retries;
 433         int i;
 434         unsigned char value[6];
 435         unsigned char ser_cont;
 436
 437         ser_cont = (len & 0x07) | 0x10;
 438
 439         value[0] = addr;
 440         value[1] = ser_cont;
 441         for (i = 0; i < len; i++)
 442                 value[i + 2] = buf[i];
 443
 444         for (retries = 5;;) {
 445                 rc = usb_control_msg(usbvision->dev,
 446                                      usb_sndctrlpipe(usbvision->dev, 1),
 447                                      USBVISION_OP_CODE,
 448                                      USB_DIR_OUT | USB_TYPE_VENDOR |
 449                                      USB_RECIP_ENDPOINT, 0,
 450                                      (__u16) USBVISION_SER_ADRS, value,
 451                                      len + 2, HZ);
 452
 453                 if (rc < 0)
 454                         return rc;
 455
 456                 rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT,
 457                                       (len & 0x07) | 0x10);
 458                 if (rc < 0)
 459                         return rc;
 460
 461                 /* Test for Busy and ACK */
 462                 do {
 463                         rc = usbvision_read_reg(usbvision, USBVISION_SER_CONT);
 464                 } while (rc > 0 && ((rc & 0x10) != 0)); /* Retry while busy */
 465                 if (rc < 0)
 466                         return rc;
 467
 468                 if ((rc & 0x20) == 0)   /* Ack? */
 469                         break;
 470
 471                 /* I2C abort */
 472                 usbvision_write_reg(usbvision, USBVISION_SER_CONT, 0x00);
 473
 474                 if (--retries < 0)
 475                         return -1;
 476
 477         }
 478
 479         if (i2c_debug & DBG_I2C) {
 480                 int idx;
 481                 for (idx = 0; idx < len; idx++) {
 482                         PDEBUG(DBG_I2C,"wrote %x at address %x", (unsigned char)buf[idx], addr);
 483                 }
 484         }
 485         return len;
 486 }
 487
 488 static int usbvision_i2c_write(void *data, unsigned char addr, char *buf,
 489                             short len)
 490 {
 491         char *bufPtr = buf;
 492         int retval;
 493         int wrcount = 0;
 494         int count;
 495         int maxLen = 4;
 496         struct usb_usbvision *usbvision = (struct usb_usbvision *) data;
 497
 498         while (len > 0) {
 499                 count = (len > maxLen) ? maxLen : len;
 500                 retval = usbvision_i2c_write_max4(usbvision, addr, bufPtr, count);
 501                 if (retval > 0) {
 502                         len -= count;
 503                         bufPtr += count;
 504                         wrcount += count;
 505                 } else
 506                         return (retval < 0) ? retval : -EFAULT;
 507         }
 508         return wrcount;
 509 }
 510
 511 static int usbvision_i2c_read(void *data, unsigned char addr, char *buf,
 512                            short len)
 513 {
 514         char temp[4];
 515         int retval, i;
 516         int rdcount = 0;
 517         int count;
 518         struct usb_usbvision *usbvision = (struct usb_usbvision *) data;
 519
 520         while (len > 0) {
 521                 count = (len > 3) ? 4 : len;
 522                 retval = usbvision_i2c_read_max4(usbvision, addr, temp, count);
 523                 if (retval > 0) {
 524                         for (i = 0; i < len; i++)
 525                                 buf[rdcount + i] = temp[i];
 526                         len -= count;
 527                         rdcount += count;
 528                 } else
 529                         return (retval < 0) ? retval : -EFAULT;
 530         }
 531         return rdcount;
 532 }
 533
 534 static struct i2c_algo_usb_data i2c_algo_template = {
 535         .data           = NULL,
 536         .inb            = usbvision_i2c_read,
 537         .outb           = usbvision_i2c_write,
 538         .udelay         = 10,
 539         .mdelay         = 10,
 540         .timeout        = 100,
 541 };
 542
 543 static struct i2c_adapter i2c_adap_template = {
 544         .owner = THIS_MODULE,
 545         .name              = "usbvision",
 546         .id                = I2C_HW_B_BT848, /* FIXME */
 547         .algo              = NULL,
 548         .algo_data         = NULL,
 549         .client_register   = attach_inform,
 550         .client_unregister = detach_inform,
 551 #ifdef I2C_ADAP_CLASS_TV_ANALOG
 552         .class             = I2C_ADAP_CLASS_TV_ANALOG,
 553 #else
 554         .class             = I2C_CLASS_TV_ANALOG,
 555 #endif
 556 };
 557
 558 static struct i2c_client i2c_client_template = {
 559         .name           = "usbvision internal",
 560 };
 561
 562 EXPORT_SYMBOL(usbvision_i2c_usb_add_bus);
 563 EXPORT_SYMBOL(usbvision_i2c_usb_del_bus);
 564
 565 /*
 566  * Overrides for Emacs so that we follow Linus's tabbing style.
 567  * ---------------------------------------------------------------------------
 568  * Local variables:
 569  * c-basic-offset: 8
 570  * End:
 571  */