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