git.oblomov.eu Git - linux-2.6/blob - 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                         info("[%s:%d] " fmt, __func__, __LINE__ , ## args); \
  51         }
  52
  53 static int usbvision_i2c_write(struct usb_usbvision *usbvision, unsigned char addr, char *buf,
  54                             short len);
  55 static int usbvision_i2c_read(struct usb_usbvision *usbvision, 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 usb_usbvision *usbvision;
  62         int i, ret = -1;
  63         char buf[4];
  64
  65         usbvision = (struct usb_usbvision *)i2c_get_adapdata(i2c_adap);
  66         buf[0] = 0x00;
  67         for (i = 0; i <= retries; i++) {
  68                 ret = (usbvision_i2c_write(usbvision, 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_I2C,"Needed %d retries for address %#2x", i, addr);
  78                 PDEBUG(DBG_I2C,"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         struct usb_usbvision *usbvision;
  87         int i, ret = -1;
  88         char buf[4];
  89
  90         usbvision = (struct usb_usbvision *)i2c_get_adapdata(i2c_adap);
  91         for (i = 0; i <= retries; i++) {
  92                 ret = (usbvision_i2c_read(usbvision, 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_I2C,"Needed %d retries for address %#2x", i, addr);
 102                 PDEBUG(DBG_I2C,"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
 140                 add[0] = addr;
 141                 if (flags & I2C_M_RD)
 142                         ret = try_read_address(i2c_adap, addr, retries);
 143                 else
 144                         ret = try_write_address(i2c_adap, addr, retries);
 145
 146                 if (ret != 1) {
 147                         return -EREMOTEIO;
 148                 }
 149         }
 150         return 0;
 151 }
 152
 153 static int
 154 usbvision_i2c_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg msgs[], int num)
 155 {
 156         struct i2c_msg *pmsg;
 157         struct usb_usbvision *usbvision;
 158         int i, ret;
 159         unsigned char addr;
 160
 161         usbvision = (struct usb_usbvision *)i2c_get_adapdata(i2c_adap);
 162
 163         for (i = 0; i < num; i++) {
 164                 pmsg = &msgs[i];
 165                 ret = usb_find_address(i2c_adap, pmsg, i2c_adap->retries, &addr);
 166                 if (ret != 0) {
 167                         PDEBUG(DBG_I2C,"got NAK from device, message #%d", i);
 168                         return (ret < 0) ? ret : -EREMOTEIO;
 169                 }
 170
 171                 if (pmsg->flags & I2C_M_RD) {
 172                         /* read bytes into buffer */
 173                         ret = (usbvision_i2c_read(usbvision, addr, pmsg->buf, pmsg->len));
 174                         if (ret < pmsg->len) {
 175                                 return (ret < 0) ? ret : -EREMOTEIO;
 176                         }
 177                 } else {
 178                         /* write bytes from buffer */
 179                         ret = (usbvision_i2c_write(usbvision, addr, pmsg->buf, pmsg->len));
 180                         if (ret < pmsg->len) {
 181                                 return (ret < 0) ? ret : -EREMOTEIO;
 182                         }
 183                 }
 184         }
 185         return num;
 186 }
 187
 188 static u32 functionality(struct i2c_adapter *adap)
 189 {
 190         return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR;
 191 }
 192
 193 /* -----exported algorithm data: -------------------------------------  */
 194
 195 static struct i2c_algorithm usbvision_algo = {
 196         .master_xfer   = usbvision_i2c_xfer,
 197         .smbus_xfer    = NULL,
 198         .functionality = functionality,
 199 };
 200
 201
 202 /*
 203  * registering functions to load algorithms at runtime
 204  */
 205 static int usbvision_i2c_usb_add_bus(struct i2c_adapter *adap)
 206 {
 207         PDEBUG(DBG_I2C, "I2C   debugging is enabled [i2c]");
 208         PDEBUG(DBG_I2C, "ALGO   debugging is enabled [i2c]");
 209
 210         /* register new adapter to i2c module... */
 211
 212         adap->algo = &usbvision_algo;
 213
 214         adap->timeout = 100;    /* default values, should       */
 215         adap->retries = 3;      /* be replaced by defines       */
 216
 217         i2c_add_adapter(adap);
 218
 219         PDEBUG(DBG_I2C,"i2c bus for %s registered", adap->name);
 220
 221         return 0;
 222 }
 223
 224 /* ----------------------------------------------------------------------- */
 225 /* usbvision specific I2C functions                                        */
 226 /* ----------------------------------------------------------------------- */
 227 static struct i2c_adapter i2c_adap_template;
 228 static struct i2c_client i2c_client_template;
 229
 230 int usbvision_i2c_register(struct usb_usbvision *usbvision)
 231 {
 232         memcpy(&usbvision->i2c_adap, &i2c_adap_template,
 233                sizeof(struct i2c_adapter));
 234         memcpy(&usbvision->i2c_client, &i2c_client_template,
 235                sizeof(struct i2c_client));
 236
 237         sprintf(usbvision->i2c_adap.name + strlen(usbvision->i2c_adap.name),
 238                 " #%d", usbvision->vdev->minor & 0x1f);
 239         PDEBUG(DBG_I2C,"Adaptername: %s", usbvision->i2c_adap.name);
 240         usbvision->i2c_adap.dev.parent = &usbvision->dev->dev;
 241
 242         i2c_set_adapdata(&usbvision->i2c_adap, usbvision);
 243         i2c_set_clientdata(&usbvision->i2c_client, usbvision);
 244
 245         usbvision->i2c_client.adapter = &usbvision->i2c_adap;
 246
 247         if (usbvision_write_reg(usbvision, USBVISION_SER_MODE, USBVISION_IIC_LRNACK) < 0) {
 248                 printk(KERN_ERR "usbvision_register: can't write reg\n");
 249                 return -EBUSY;
 250         }
 251
 252 #ifdef CONFIG_MODULES
 253         /* Request the load of the i2c modules we need */
 254         switch (usbvision_device_data[usbvision->DevModel].Codec) {
 255         case CODEC_SAA7113:
 256                 request_module("saa7115");
 257                 break;
 258         case CODEC_SAA7111:
 259                 request_module("saa7115");
 260                 break;
 261         }
 262         if (usbvision_device_data[usbvision->DevModel].Tuner == 1) {
 263                 request_module("tuner");
 264         }
 265 #endif
 266
 267         return usbvision_i2c_usb_add_bus(&usbvision->i2c_adap);
 268 }
 269
 270 int usbvision_i2c_unregister(struct usb_usbvision *usbvision)
 271 {
 272
 273         i2c_del_adapter(&(usbvision->i2c_adap));
 274
 275         PDEBUG(DBG_I2C,"i2c bus for %s unregistered", usbvision->i2c_adap.name);
 276
 277         return 0;
 278 }
 279
 280 void call_i2c_clients(struct usb_usbvision *usbvision, unsigned int cmd,
 281                       void *arg)
 282 {
 283         i2c_clients_command(&usbvision->i2c_adap, cmd, arg);
 284 }
 285
 286 static int attach_inform(struct i2c_client *client)
 287 {
 288         struct usb_usbvision *usbvision;
 289
 290         usbvision = (struct usb_usbvision *)i2c_get_adapdata(client->adapter);
 291
 292         switch (client->addr << 1) {
 293                 case 0x42 << 1:
 294                 case 0x43 << 1:
 295                 case 0x4a << 1:
 296                 case 0x4b << 1:
 297                         PDEBUG(DBG_I2C,"attach_inform: tda9887 detected.");
 298                         break;
 299                 case 0x42:
 300                         PDEBUG(DBG_I2C,"attach_inform: saa7114 detected.");
 301                         break;
 302                 case 0x4a:
 303                         PDEBUG(DBG_I2C,"attach_inform: saa7113 detected.");
 304                         break;
 305                 case 0x48:
 306                         PDEBUG(DBG_I2C,"attach_inform: saa7111 detected.");
 307                         break;
 308                 case 0xa0:
 309                         PDEBUG(DBG_I2C,"attach_inform: eeprom detected.");
 310                         break;
 311
 312                 default:
 313                         {
 314                                 struct tuner_setup tun_setup;
 315
 316                                 PDEBUG(DBG_I2C,"attach inform: detected I2C address %x", client->addr << 1);
 317                                 usbvision->tuner_addr = client->addr;
 318
 319                                 if ((usbvision->have_tuner) && (usbvision->tuner_type != -1)) {
 320                                         tun_setup.mode_mask = T_ANALOG_TV | T_RADIO;
 321                                         tun_setup.type = usbvision->tuner_type;
 322                                         tun_setup.addr = usbvision->tuner_addr;
 323                                         call_i2c_clients(usbvision, TUNER_SET_TYPE_ADDR, &tun_setup);
 324                                 }
 325                         }
 326                         break;
 327         }
 328         return 0;
 329 }
 330
 331 static int detach_inform(struct i2c_client *client)
 332 {
 333         struct usb_usbvision *usbvision;
 334
 335         usbvision = (struct usb_usbvision *)i2c_get_adapdata(client->adapter);
 336
 337         PDEBUG(DBG_I2C,"usbvision[%d] detaches %s", usbvision->nr, client->name);
 338         return 0;
 339 }
 340
 341 static int
 342 usbvision_i2c_read_max4(struct usb_usbvision *usbvision, unsigned char addr,
 343                      char *buf, short len)
 344 {
 345         int rc, retries;
 346
 347         for (retries = 5;;) {
 348                 rc = usbvision_write_reg(usbvision, USBVISION_SER_ADRS, addr);
 349                 if (rc < 0)
 350                         return rc;
 351
 352                 /* Initiate byte read cycle                    */
 353                 /* USBVISION_SER_CONT <- d0-d2 n. of bytes to r/w */
 354                 /*                    d3 0=Wr 1=Rd             */
 355                 rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT,
 356                                       (len & 0x07) | 0x18);
 357                 if (rc < 0)
 358                         return rc;
 359
 360                 /* Test for Busy and ACK */
 361                 do {
 362                         /* USBVISION_SER_CONT -> d4 == 0 busy */
 363                         rc = usbvision_read_reg(usbvision, USBVISION_SER_CONT);
 364                 } while (rc > 0 && ((rc & 0x10) != 0)); /* Retry while busy */
 365                 if (rc < 0)
 366                         return rc;
 367
 368                 /* USBVISION_SER_CONT -> d5 == 1 Not ack */
 369                 if ((rc & 0x20) == 0)   /* Ack? */
 370                         break;
 371
 372                 /* I2C abort */
 373                 rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT, 0x00);
 374                 if (rc < 0)
 375                         return rc;
 376
 377                 if (--retries < 0)
 378                         return -1;
 379         }
 380
 381         switch (len) {
 382         case 4:
 383                 buf[3] = usbvision_read_reg(usbvision, USBVISION_SER_DAT4);
 384         case 3:
 385                 buf[2] = usbvision_read_reg(usbvision, USBVISION_SER_DAT3);
 386         case 2:
 387                 buf[1] = usbvision_read_reg(usbvision, USBVISION_SER_DAT2);
 388         case 1:
 389                 buf[0] = usbvision_read_reg(usbvision, USBVISION_SER_DAT1);
 390                 break;
 391         default:
 392                 printk(KERN_ERR
 393                        "usbvision_i2c_read_max4: buffer length > 4\n");
 394         }
 395
 396         if (i2c_debug & DBG_I2C) {
 397                 int idx;
 398                 for (idx = 0; idx < len; idx++) {
 399                         PDEBUG(DBG_I2C,"read %x from address %x", (unsigned char)buf[idx], addr);
 400                 }
 401         }
 402         return len;
 403 }
 404
 405
 406 static int usbvision_i2c_write_max4(struct usb_usbvision *usbvision,
 407                                  unsigned char addr, const char *buf,
 408                                  short len)
 409 {
 410         int rc, retries;
 411         int i;
 412         unsigned char value[6];
 413         unsigned char ser_cont;
 414
 415         ser_cont = (len & 0x07) | 0x10;
 416
 417         value[0] = addr;
 418         value[1] = ser_cont;
 419         for (i = 0; i < len; i++)
 420                 value[i + 2] = buf[i];
 421
 422         for (retries = 5;;) {
 423                 rc = usb_control_msg(usbvision->dev,
 424                                      usb_sndctrlpipe(usbvision->dev, 1),
 425                                      USBVISION_OP_CODE,
 426                                      USB_DIR_OUT | USB_TYPE_VENDOR |
 427                                      USB_RECIP_ENDPOINT, 0,
 428                                      (__u16) USBVISION_SER_ADRS, value,
 429                                      len + 2, HZ);
 430
 431                 if (rc < 0)
 432                         return rc;
 433
 434                 rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT,
 435                                       (len & 0x07) | 0x10);
 436                 if (rc < 0)
 437                         return rc;
 438
 439                 /* Test for Busy and ACK */
 440                 do {
 441                         rc = usbvision_read_reg(usbvision, USBVISION_SER_CONT);
 442                 } while (rc > 0 && ((rc & 0x10) != 0)); /* Retry while busy */
 443                 if (rc < 0)
 444                         return rc;
 445
 446                 if ((rc & 0x20) == 0)   /* Ack? */
 447                         break;
 448
 449                 /* I2C abort */
 450                 usbvision_write_reg(usbvision, USBVISION_SER_CONT, 0x00);
 451
 452                 if (--retries < 0)
 453                         return -1;
 454
 455         }
 456
 457         if (i2c_debug & DBG_I2C) {
 458                 int idx;
 459                 for (idx = 0; idx < len; idx++) {
 460                         PDEBUG(DBG_I2C,"wrote %x at address %x", (unsigned char)buf[idx], addr);
 461                 }
 462         }
 463         return len;
 464 }
 465
 466 static int usbvision_i2c_write(struct usb_usbvision *usbvision, unsigned char addr, char *buf,
 467                             short len)
 468 {
 469         char *bufPtr = buf;
 470         int retval;
 471         int wrcount = 0;
 472         int count;
 473         int maxLen = 4;
 474
 475         while (len > 0) {
 476                 count = (len > maxLen) ? maxLen : len;
 477                 retval = usbvision_i2c_write_max4(usbvision, addr, bufPtr, count);
 478                 if (retval > 0) {
 479                         len -= count;
 480                         bufPtr += count;
 481                         wrcount += count;
 482                 } else
 483                         return (retval < 0) ? retval : -EFAULT;
 484         }
 485         return wrcount;
 486 }
 487
 488 static int usbvision_i2c_read(struct usb_usbvision *usbvision, unsigned char addr, char *buf,
 489                            short len)
 490 {
 491         char temp[4];
 492         int retval, i;
 493         int rdcount = 0;
 494         int count;
 495
 496         while (len > 0) {
 497                 count = (len > 3) ? 4 : len;
 498                 retval = usbvision_i2c_read_max4(usbvision, addr, temp, count);
 499                 if (retval > 0) {
 500                         for (i = 0; i < len; i++)
 501                                 buf[rdcount + i] = temp[i];
 502                         len -= count;
 503                         rdcount += count;
 504                 } else
 505                         return (retval < 0) ? retval : -EFAULT;
 506         }
 507         return rdcount;
 508 }
 509
 510 static struct i2c_adapter i2c_adap_template = {
 511         .owner = THIS_MODULE,
 512         .name              = "usbvision",
 513         .id                = I2C_HW_B_BT848, /* FIXME */
 514         .client_register   = attach_inform,
 515         .client_unregister = detach_inform,
 516         .class             = I2C_CLASS_TV_ANALOG,
 517 };
 518
 519 static struct i2c_client i2c_client_template = {
 520         .name           = "usbvision internal",
 521 };
 522
 523 /*
 524  * Overrides for Emacs so that we follow Linus's tabbing style.
 525  * ---------------------------------------------------------------------------
 526  * Local variables:
 527  * c-basic-offset: 8
 528  * End:
 529  */