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         void *data;
  62         int i, ret = -1;
  63         char buf[4];
  64
  65         data = i2c_get_adapdata(i2c_adap);
  66         buf[0] = 0x00;
  67         for (i = 0; i <= retries; i++) {
  68                 ret = (usbvision_i2c_write(data, addr, buf, 1));
  69                 if (ret == 1)
  70                         break;  /* success! */
  71                 udelay(5);
  72                 if (i == retries)       /* no success */
  73                         break;
  74                 udelay(10);
  75         }
  76         if (i) {
  77                 PDEBUG(DBG_ALGO,"Needed %d retries for address %#2x", i, addr);
  78                 PDEBUG(DBG_ALGO,"Maybe there's no device at this address");
  79         }
  80         return ret;
  81 }
  82
  83 static inline int try_read_address(struct i2c_adapter *i2c_adap,
  84                                    unsigned char addr, int retries)
  85 {
  86         void *data;
  87         int i, ret = -1;
  88         char buf[4];
  89
  90         data = i2c_get_adapdata(i2c_adap);
  91         for (i = 0; i <= retries; i++) {
  92                 ret = (usbvision_i2c_read(data, addr, buf, 1));
  93                 if (ret == 1)
  94                         break;  /* success! */
  95                 udelay(5);
  96                 if (i == retries)       /* no success */
  97                         break;
  98                 udelay(10);
  99         }
 100         if (i) {
 101                 PDEBUG(DBG_ALGO,"Needed %d retries for address %#2x", i, addr);
 102                 PDEBUG(DBG_ALGO,"Maybe there's no device at this address");
 103         }
 104         return ret;
 105 }
 106
 107 static inline int usb_find_address(struct i2c_adapter *i2c_adap,
 108                                    struct i2c_msg *msg, int retries,
 109                                    unsigned char *add)
 110 {
 111         unsigned short flags = msg->flags;
 112
 113         unsigned char addr;
 114         int ret;
 115         if ((flags & I2C_M_TEN)) {
 116                 /* a ten bit address */
 117                 addr = 0xf0 | ((msg->addr >> 7) & 0x03);
 118                 /* try extended address code... */
 119                 ret = try_write_address(i2c_adap, addr, retries);
 120                 if (ret != 1) {
 121                         err("died at extended address code, while writing");
 122                         return -EREMOTEIO;
 123                 }
 124                 add[0] = addr;
 125                 if (flags & I2C_M_RD) {
 126                         /* okay, now switch into reading mode */
 127                         addr |= 0x01;
 128                         ret = try_read_address(i2c_adap, addr, retries);
 129                         if (ret != 1) {
 130                                 err("died at extended address code, while reading");
 131                                 return -EREMOTEIO;
 132                         }
 133                 }
 134
 135         } else {                /* normal 7bit address  */
 136                 addr = (msg->addr << 1);
 137                 if (flags & I2C_M_RD)
 138                         addr |= 1;
 139                 if (flags & I2C_M_REV_DIR_ADDR)
 140                         addr ^= 1;
 141
 142                 add[0] = addr;
 143                 if (flags & I2C_M_RD)
 144                         ret = try_read_address(i2c_adap, addr, retries);
 145                 else
 146                         ret = try_write_address(i2c_adap, addr, retries);
 147
 148                 if (ret != 1) {
 149                         return -EREMOTEIO;
 150                 }
 151         }
 152         return 0;
 153 }
 154
 155 static int
 156 usb_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg msgs[], int num)
 157 {
 158         struct i2c_msg *pmsg;
 159         void *data;
 160         int i, ret;
 161         unsigned char addr;
 162
 163         data = i2c_get_adapdata(i2c_adap);
 164
 165         for (i = 0; i < num; i++) {
 166                 pmsg = &msgs[i];
 167                 ret = usb_find_address(i2c_adap, pmsg, i2c_adap->retries, &addr);
 168                 if (ret != 0) {
 169                         PDEBUG(DBG_ALGO,"got NAK from device, message #%d", i);
 170                         return (ret < 0) ? ret : -EREMOTEIO;
 171                 }
 172
 173                 if (pmsg->flags & I2C_M_RD) {
 174                         /* read bytes into buffer */
 175                         ret = (usbvision_i2c_read(data, addr, pmsg->buf, pmsg->len));
 176                         if (ret < pmsg->len) {
 177                                 return (ret < 0) ? ret : -EREMOTEIO;
 178                         }
 179                 } else {
 180                         /* write bytes from buffer */
 181                         ret = (usbvision_i2c_write(data, addr, pmsg->buf, pmsg->len));
 182                         if (ret < pmsg->len) {
 183                                 return (ret < 0) ? ret : -EREMOTEIO;
 184                         }
 185                 }
 186         }
 187         return num;
 188 }
 189
 190 static int algo_control(struct i2c_adapter *adapter, unsigned int cmd, unsigned long arg)
 191 {
 192         return 0;
 193 }
 194
 195 static u32 usb_func(struct i2c_adapter *adap)
 196 {
 197         return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR | I2C_FUNC_PROTOCOL_MANGLING;
 198 }
 199
 200
 201 /* -----exported algorithm data: -------------------------------------  */
 202
 203 static struct i2c_algorithm i2c_usb_algo = {
 204         .master_xfer   = usb_xfer,
 205         .smbus_xfer    = NULL,
 206         .algo_control  = algo_control,
 207         .functionality = usb_func,
 208 };
 209
 210
 211 /*
 212  * registering functions to load algorithms at runtime
 213  */
 214 static int usbvision_i2c_usb_add_bus(struct i2c_adapter *adap)
 215 {
 216         PDEBUG(DBG_I2C, "I2C   debugging is enabled [i2c]");
 217         PDEBUG(DBG_ALGO, "ALGO   debugging is enabled [i2c]");
 218
 219         /* register new adapter to i2c module... */
 220
 221         adap->algo = &i2c_usb_algo;
 222
 223         adap->timeout = 100;    /* default values, should       */
 224         adap->retries = 3;      /* be replaced by defines       */
 225
 226         i2c_add_adapter(adap);
 227
 228         PDEBUG(DBG_ALGO,"i2c bus for %s registered", adap->name);
 229
 230         return 0;
 231 }
 232
 233
 234 int usbvision_i2c_usb_del_bus(struct i2c_adapter *adap)
 235 {
 236
 237         i2c_del_adapter(adap);
 238
 239         PDEBUG(DBG_ALGO,"i2c bus for %s unregistered", adap->name);
 240
 241         return 0;
 242 }
 243
 244
 245 /* ----------------------------------------------------------------------- */
 246 /* usbvision specific I2C functions                                        */
 247 /* ----------------------------------------------------------------------- */
 248 static struct i2c_adapter i2c_adap_template;
 249 static struct i2c_client i2c_client_template;
 250
 251 int usbvision_init_i2c(struct usb_usbvision *usbvision)
 252 {
 253         memcpy(&usbvision->i2c_adap, &i2c_adap_template,
 254                sizeof(struct i2c_adapter));
 255         memcpy(&usbvision->i2c_client, &i2c_client_template,
 256                sizeof(struct i2c_client));
 257
 258         sprintf(usbvision->i2c_adap.name + strlen(usbvision->i2c_adap.name),
 259                 " #%d", usbvision->vdev->minor & 0x1f);
 260         PDEBUG(DBG_I2C,"Adaptername: %s", usbvision->i2c_adap.name);
 261
 262         i2c_set_adapdata(&usbvision->i2c_adap, usbvision);
 263         i2c_set_clientdata(&usbvision->i2c_client, usbvision);
 264
 265         usbvision->i2c_client.adapter = &usbvision->i2c_adap;
 266
 267         if (usbvision_write_reg(usbvision, USBVISION_SER_MODE, USBVISION_IIC_LRNACK) < 0) {
 268                 printk(KERN_ERR "usbvision_init_i2c: can't write reg\n");
 269                 return -EBUSY;
 270         }
 271
 272 #ifdef CONFIG_MODULES
 273         /* Request the load of the i2c modules we need */
 274         switch (usbvision_device_data[usbvision->DevModel].Codec) {
 275         case CODEC_SAA7113:
 276                 request_module("saa7115");
 277                 break;
 278         case CODEC_SAA7111:
 279                 request_module("saa7115");
 280                 break;
 281         }
 282         if (usbvision_device_data[usbvision->DevModel].Tuner == 1) {
 283                 request_module("tuner");
 284         }
 285 #endif
 286
 287         return usbvision_i2c_usb_add_bus(&usbvision->i2c_adap);
 288 }
 289
 290 void call_i2c_clients(struct usb_usbvision *usbvision, unsigned int cmd,
 291                       void *arg)
 292 {
 293         i2c_clients_command(&usbvision->i2c_adap, cmd, arg);
 294 }
 295
 296 static int attach_inform(struct i2c_client *client)
 297 {
 298         struct usb_usbvision *usbvision;
 299
 300         usbvision = (struct usb_usbvision *)i2c_get_adapdata(client->adapter);
 301
 302         switch (client->addr << 1) {
 303                 case 0x43:
 304                 case 0x4b:
 305                 {
 306                         struct tuner_setup tun_setup;
 307
 308                         tun_setup.mode_mask = T_ANALOG_TV | T_RADIO;
 309                         tun_setup.type = TUNER_TDA9887;
 310                         tun_setup.addr = client->addr;
 311
 312                         call_i2c_clients(usbvision, TUNER_SET_TYPE_ADDR, &tun_setup);
 313
 314                         break;
 315                 }
 316                 case 0x42:
 317                         PDEBUG(DBG_I2C,"attach_inform: saa7114 detected.");
 318                         break;
 319                 case 0x4a:
 320                         PDEBUG(DBG_I2C,"attach_inform: saa7113 detected.");
 321                         break;
 322                 case 0x48:
 323                         PDEBUG(DBG_I2C,"attach_inform: saa7111 detected.");
 324                         break;
 325                 case 0xa0:
 326                         PDEBUG(DBG_I2C,"attach_inform: eeprom detected.");
 327                         break;
 328
 329                 default:
 330                         {
 331                                 struct tuner_setup tun_setup;
 332
 333                                 PDEBUG(DBG_I2C,"attach inform: detected I2C address %x", client->addr << 1);
 334                                 usbvision->tuner_addr = client->addr;
 335
 336                                 if ((usbvision->have_tuner) && (usbvision->tuner_type != -1)) {
 337                                         tun_setup.mode_mask = T_ANALOG_TV | T_RADIO;
 338                                         tun_setup.type = usbvision->tuner_type;
 339                                         tun_setup.addr = usbvision->tuner_addr;
 340                                         call_i2c_clients(usbvision, TUNER_SET_TYPE_ADDR, &tun_setup);
 341                                 }
 342                         }
 343                         break;
 344         }
 345         return 0;
 346 }
 347
 348 static int detach_inform(struct i2c_client *client)
 349 {
 350         struct usb_usbvision *usbvision;
 351
 352         usbvision = (struct usb_usbvision *)i2c_get_adapdata(client->adapter);
 353
 354         PDEBUG(DBG_I2C,"usbvision[%d] detaches %s", usbvision->nr, client->name);
 355         return 0;
 356 }
 357
 358 static int
 359 usbvision_i2c_read_max4(struct usb_usbvision *usbvision, unsigned char addr,
 360                      char *buf, short len)
 361 {
 362         int rc, retries;
 363
 364         for (retries = 5;;) {
 365                 rc = usbvision_write_reg(usbvision, USBVISION_SER_ADRS, addr);
 366                 if (rc < 0)
 367                         return rc;
 368
 369                 /* Initiate byte read cycle                    */
 370                 /* USBVISION_SER_CONT <- d0-d2 n. of bytes to r/w */
 371                 /*                    d3 0=Wr 1=Rd             */
 372                 rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT,
 373                                       (len & 0x07) | 0x18);
 374                 if (rc < 0)
 375                         return rc;
 376
 377                 /* Test for Busy and ACK */
 378                 do {
 379                         /* USBVISION_SER_CONT -> d4 == 0 busy */
 380                         rc = usbvision_read_reg(usbvision, USBVISION_SER_CONT);
 381                 } while (rc > 0 && ((rc & 0x10) != 0)); /* Retry while busy */
 382                 if (rc < 0)
 383                         return rc;
 384
 385                 /* USBVISION_SER_CONT -> d5 == 1 Not ack */
 386                 if ((rc & 0x20) == 0)   /* Ack? */
 387                         break;
 388
 389                 /* I2C abort */
 390                 rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT, 0x00);
 391                 if (rc < 0)
 392                         return rc;
 393
 394                 if (--retries < 0)
 395                         return -1;
 396         }
 397
 398         switch (len) {
 399         case 4:
 400                 buf[3] = usbvision_read_reg(usbvision, USBVISION_SER_DAT4);
 401         case 3:
 402                 buf[2] = usbvision_read_reg(usbvision, USBVISION_SER_DAT3);
 403         case 2:
 404                 buf[1] = usbvision_read_reg(usbvision, USBVISION_SER_DAT2);
 405         case 1:
 406                 buf[0] = usbvision_read_reg(usbvision, USBVISION_SER_DAT1);
 407                 break;
 408         default:
 409                 printk(KERN_ERR
 410                        "usbvision_i2c_read_max4: buffer length > 4\n");
 411         }
 412
 413         if (i2c_debug & DBG_I2C) {
 414                 int idx;
 415                 for (idx = 0; idx < len; idx++) {
 416                         PDEBUG(DBG_I2C,"read %x from address %x", (unsigned char)buf[idx], addr);
 417                 }
 418         }
 419         return len;
 420 }
 421
 422
 423 static int usbvision_i2c_write_max4(struct usb_usbvision *usbvision,
 424                                  unsigned char addr, const char *buf,
 425                                  short len)
 426 {
 427         int rc, retries;
 428         int i;
 429         unsigned char value[6];
 430         unsigned char ser_cont;
 431
 432         ser_cont = (len & 0x07) | 0x10;
 433
 434         value[0] = addr;
 435         value[1] = ser_cont;
 436         for (i = 0; i < len; i++)
 437                 value[i + 2] = buf[i];
 438
 439         for (retries = 5;;) {
 440                 rc = usb_control_msg(usbvision->dev,
 441                                      usb_sndctrlpipe(usbvision->dev, 1),
 442                                      USBVISION_OP_CODE,
 443                                      USB_DIR_OUT | USB_TYPE_VENDOR |
 444                                      USB_RECIP_ENDPOINT, 0,
 445                                      (__u16) USBVISION_SER_ADRS, value,
 446                                      len + 2, HZ);
 447
 448                 if (rc < 0)
 449                         return rc;
 450
 451                 rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT,
 452                                       (len & 0x07) | 0x10);
 453                 if (rc < 0)
 454                         return rc;
 455
 456                 /* Test for Busy and ACK */
 457                 do {
 458                         rc = usbvision_read_reg(usbvision, USBVISION_SER_CONT);
 459                 } while (rc > 0 && ((rc & 0x10) != 0)); /* Retry while busy */
 460                 if (rc < 0)
 461                         return rc;
 462
 463                 if ((rc & 0x20) == 0)   /* Ack? */
 464                         break;
 465
 466                 /* I2C abort */
 467                 usbvision_write_reg(usbvision, USBVISION_SER_CONT, 0x00);
 468
 469                 if (--retries < 0)
 470                         return -1;
 471
 472         }
 473
 474         if (i2c_debug & DBG_I2C) {
 475                 int idx;
 476                 for (idx = 0; idx < len; idx++) {
 477                         PDEBUG(DBG_I2C,"wrote %x at address %x", (unsigned char)buf[idx], addr);
 478                 }
 479         }
 480         return len;
 481 }
 482
 483 static int usbvision_i2c_write(void *data, unsigned char addr, char *buf,
 484                             short len)
 485 {
 486         char *bufPtr = buf;
 487         int retval;
 488         int wrcount = 0;
 489         int count;
 490         int maxLen = 4;
 491         struct usb_usbvision *usbvision = (struct usb_usbvision *) data;
 492
 493         while (len > 0) {
 494                 count = (len > maxLen) ? maxLen : len;
 495                 retval = usbvision_i2c_write_max4(usbvision, addr, bufPtr, count);
 496                 if (retval > 0) {
 497                         len -= count;
 498                         bufPtr += count;
 499                         wrcount += count;
 500                 } else
 501                         return (retval < 0) ? retval : -EFAULT;
 502         }
 503         return wrcount;
 504 }
 505
 506 static int usbvision_i2c_read(void *data, unsigned char addr, char *buf,
 507                            short len)
 508 {
 509         char temp[4];
 510         int retval, i;
 511         int rdcount = 0;
 512         int count;
 513         struct usb_usbvision *usbvision = (struct usb_usbvision *) data;
 514
 515         while (len > 0) {
 516                 count = (len > 3) ? 4 : len;
 517                 retval = usbvision_i2c_read_max4(usbvision, addr, temp, count);
 518                 if (retval > 0) {
 519                         for (i = 0; i < len; i++)
 520                                 buf[rdcount + i] = temp[i];
 521                         len -= count;
 522                         rdcount += count;
 523                 } else
 524                         return (retval < 0) ? retval : -EFAULT;
 525         }
 526         return rdcount;
 527 }
 528
 529 static struct i2c_adapter i2c_adap_template = {
 530         .owner = THIS_MODULE,
 531         .name              = "usbvision",
 532         .id                = I2C_HW_B_BT848, /* FIXME */
 533         .client_register   = attach_inform,
 534         .client_unregister = detach_inform,
 535 #ifdef I2C_ADAP_CLASS_TV_ANALOG
 536         .class             = I2C_ADAP_CLASS_TV_ANALOG,
 537 #else
 538         .class             = I2C_CLASS_TV_ANALOG,
 539 #endif
 540 };
 541
 542 static struct i2c_client i2c_client_template = {
 543         .name           = "usbvision internal",
 544 };
 545
 546 /*
 547  * Overrides for Emacs so that we follow Linus's tabbing style.
 548  * ---------------------------------------------------------------------------
 549  * Local variables:
 550  * c-basic-offset: 8
 551  * End:
 552  */