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                 if (flags & I2C_M_REV_DIR_ADDR)
 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 int algo_control(struct i2c_adapter *adapter, unsigned int cmd, unsigned long arg)
 189 {
 190         return 0;
 191 }
 192
 193 static u32 functionality(struct i2c_adapter *adap)
 194 {
 195         return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR | I2C_FUNC_PROTOCOL_MANGLING;
 196 }
 197
 198
 199 /* -----exported algorithm data: -------------------------------------  */
 200
 201 static struct i2c_algorithm usbvision_algo = {
 202         .master_xfer   = usbvision_i2c_xfer,
 203         .smbus_xfer    = NULL,
 204         .algo_control  = algo_control,
 205         .functionality = functionality,
 206 };
 207
 208
 209 /*
 210  * registering functions to load algorithms at runtime
 211  */
 212 static int usbvision_i2c_usb_add_bus(struct i2c_adapter *adap)
 213 {
 214         PDEBUG(DBG_I2C, "I2C   debugging is enabled [i2c]");
 215         PDEBUG(DBG_I2C, "ALGO   debugging is enabled [i2c]");
 216
 217         /* register new adapter to i2c module... */
 218
 219         adap->algo = &usbvision_algo;
 220
 221         adap->timeout = 100;    /* default values, should       */
 222         adap->retries = 3;      /* be replaced by defines       */
 223
 224         i2c_add_adapter(adap);
 225
 226         PDEBUG(DBG_I2C,"i2c bus for %s registered", adap->name);
 227
 228         return 0;
 229 }
 230
 231 /* ----------------------------------------------------------------------- */
 232 /* usbvision specific I2C functions                                        */
 233 /* ----------------------------------------------------------------------- */
 234 static struct i2c_adapter i2c_adap_template;
 235 static struct i2c_client i2c_client_template;
 236
 237 int usbvision_i2c_register(struct usb_usbvision *usbvision)
 238 {
 239         memcpy(&usbvision->i2c_adap, &i2c_adap_template,
 240                sizeof(struct i2c_adapter));
 241         memcpy(&usbvision->i2c_client, &i2c_client_template,
 242                sizeof(struct i2c_client));
 243
 244         sprintf(usbvision->i2c_adap.name + strlen(usbvision->i2c_adap.name),
 245                 " #%d", usbvision->vdev->minor & 0x1f);
 246         PDEBUG(DBG_I2C,"Adaptername: %s", usbvision->i2c_adap.name);
 247         usbvision->i2c_adap.dev.parent = &usbvision->dev->dev;
 248
 249         i2c_set_adapdata(&usbvision->i2c_adap, usbvision);
 250         i2c_set_clientdata(&usbvision->i2c_client, usbvision);
 251
 252         usbvision->i2c_client.adapter = &usbvision->i2c_adap;
 253
 254         if (usbvision_write_reg(usbvision, USBVISION_SER_MODE, USBVISION_IIC_LRNACK) < 0) {
 255                 printk(KERN_ERR "usbvision_register: can't write reg\n");
 256                 return -EBUSY;
 257         }
 258
 259 #ifdef CONFIG_MODULES
 260         /* Request the load of the i2c modules we need */
 261         switch (usbvision_device_data[usbvision->DevModel].Codec) {
 262         case CODEC_SAA7113:
 263                 request_module("saa7115");
 264                 break;
 265         case CODEC_SAA7111:
 266                 request_module("saa7115");
 267                 break;
 268         }
 269         if (usbvision_device_data[usbvision->DevModel].Tuner == 1) {
 270                 request_module("tuner");
 271         }
 272 #endif
 273
 274         return usbvision_i2c_usb_add_bus(&usbvision->i2c_adap);
 275 }
 276
 277 int usbvision_i2c_unregister(struct usb_usbvision *usbvision)
 278 {
 279
 280         i2c_del_adapter(&(usbvision->i2c_adap));
 281
 282         PDEBUG(DBG_I2C,"i2c bus for %s unregistered", usbvision->i2c_adap.name);
 283
 284         return 0;
 285 }
 286
 287 void call_i2c_clients(struct usb_usbvision *usbvision, unsigned int cmd,
 288                       void *arg)
 289 {
 290         i2c_clients_command(&usbvision->i2c_adap, cmd, arg);
 291 }
 292
 293 static int attach_inform(struct i2c_client *client)
 294 {
 295         struct usb_usbvision *usbvision;
 296
 297         usbvision = (struct usb_usbvision *)i2c_get_adapdata(client->adapter);
 298
 299         switch (client->addr << 1) {
 300                 case 0x42 << 1:
 301                 case 0x43 << 1:
 302                 case 0x4a << 1:
 303                 case 0x4b << 1:
 304                         PDEBUG(DBG_I2C,"attach_inform: tda9887 detected.");
 305                         break;
 306                 case 0x42:
 307                         PDEBUG(DBG_I2C,"attach_inform: saa7114 detected.");
 308                         break;
 309                 case 0x4a:
 310                         PDEBUG(DBG_I2C,"attach_inform: saa7113 detected.");
 311                         break;
 312                 case 0x48:
 313                         PDEBUG(DBG_I2C,"attach_inform: saa7111 detected.");
 314                         break;
 315                 case 0xa0:
 316                         PDEBUG(DBG_I2C,"attach_inform: eeprom detected.");
 317                         break;
 318
 319                 default:
 320                         {
 321                                 struct tuner_setup tun_setup;
 322
 323                                 PDEBUG(DBG_I2C,"attach inform: detected I2C address %x", client->addr << 1);
 324                                 usbvision->tuner_addr = client->addr;
 325
 326                                 if ((usbvision->have_tuner) && (usbvision->tuner_type != -1)) {
 327                                         tun_setup.mode_mask = T_ANALOG_TV | T_RADIO;
 328                                         tun_setup.type = usbvision->tuner_type;
 329                                         tun_setup.addr = usbvision->tuner_addr;
 330                                         call_i2c_clients(usbvision, TUNER_SET_TYPE_ADDR, &tun_setup);
 331                                 }
 332                         }
 333                         break;
 334         }
 335         return 0;
 336 }
 337
 338 static int detach_inform(struct i2c_client *client)
 339 {
 340         struct usb_usbvision *usbvision;
 341
 342         usbvision = (struct usb_usbvision *)i2c_get_adapdata(client->adapter);
 343
 344         PDEBUG(DBG_I2C,"usbvision[%d] detaches %s", usbvision->nr, client->name);
 345         return 0;
 346 }
 347
 348 static int
 349 usbvision_i2c_read_max4(struct usb_usbvision *usbvision, unsigned char addr,
 350                      char *buf, short len)
 351 {
 352         int rc, retries;
 353
 354         for (retries = 5;;) {
 355                 rc = usbvision_write_reg(usbvision, USBVISION_SER_ADRS, addr);
 356                 if (rc < 0)
 357                         return rc;
 358
 359                 /* Initiate byte read cycle                    */
 360                 /* USBVISION_SER_CONT <- d0-d2 n. of bytes to r/w */
 361                 /*                    d3 0=Wr 1=Rd             */
 362                 rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT,
 363                                       (len & 0x07) | 0x18);
 364                 if (rc < 0)
 365                         return rc;
 366
 367                 /* Test for Busy and ACK */
 368                 do {
 369                         /* USBVISION_SER_CONT -> d4 == 0 busy */
 370                         rc = usbvision_read_reg(usbvision, USBVISION_SER_CONT);
 371                 } while (rc > 0 && ((rc & 0x10) != 0)); /* Retry while busy */
 372                 if (rc < 0)
 373                         return rc;
 374
 375                 /* USBVISION_SER_CONT -> d5 == 1 Not ack */
 376                 if ((rc & 0x20) == 0)   /* Ack? */
 377                         break;
 378
 379                 /* I2C abort */
 380                 rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT, 0x00);
 381                 if (rc < 0)
 382                         return rc;
 383
 384                 if (--retries < 0)
 385                         return -1;
 386         }
 387
 388         switch (len) {
 389         case 4:
 390                 buf[3] = usbvision_read_reg(usbvision, USBVISION_SER_DAT4);
 391         case 3:
 392                 buf[2] = usbvision_read_reg(usbvision, USBVISION_SER_DAT3);
 393         case 2:
 394                 buf[1] = usbvision_read_reg(usbvision, USBVISION_SER_DAT2);
 395         case 1:
 396                 buf[0] = usbvision_read_reg(usbvision, USBVISION_SER_DAT1);
 397                 break;
 398         default:
 399                 printk(KERN_ERR
 400                        "usbvision_i2c_read_max4: buffer length > 4\n");
 401         }
 402
 403         if (i2c_debug & DBG_I2C) {
 404                 int idx;
 405                 for (idx = 0; idx < len; idx++) {
 406                         PDEBUG(DBG_I2C,"read %x from address %x", (unsigned char)buf[idx], addr);
 407                 }
 408         }
 409         return len;
 410 }
 411
 412
 413 static int usbvision_i2c_write_max4(struct usb_usbvision *usbvision,
 414                                  unsigned char addr, const char *buf,
 415                                  short len)
 416 {
 417         int rc, retries;
 418         int i;
 419         unsigned char value[6];
 420         unsigned char ser_cont;
 421
 422         ser_cont = (len & 0x07) | 0x10;
 423
 424         value[0] = addr;
 425         value[1] = ser_cont;
 426         for (i = 0; i < len; i++)
 427                 value[i + 2] = buf[i];
 428
 429         for (retries = 5;;) {
 430                 rc = usb_control_msg(usbvision->dev,
 431                                      usb_sndctrlpipe(usbvision->dev, 1),
 432                                      USBVISION_OP_CODE,
 433                                      USB_DIR_OUT | USB_TYPE_VENDOR |
 434                                      USB_RECIP_ENDPOINT, 0,
 435                                      (__u16) USBVISION_SER_ADRS, value,
 436                                      len + 2, HZ);
 437
 438                 if (rc < 0)
 439                         return rc;
 440
 441                 rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT,
 442                                       (len & 0x07) | 0x10);
 443                 if (rc < 0)
 444                         return rc;
 445
 446                 /* Test for Busy and ACK */
 447                 do {
 448                         rc = usbvision_read_reg(usbvision, USBVISION_SER_CONT);
 449                 } while (rc > 0 && ((rc & 0x10) != 0)); /* Retry while busy */
 450                 if (rc < 0)
 451                         return rc;
 452
 453                 if ((rc & 0x20) == 0)   /* Ack? */
 454                         break;
 455
 456                 /* I2C abort */
 457                 usbvision_write_reg(usbvision, USBVISION_SER_CONT, 0x00);
 458
 459                 if (--retries < 0)
 460                         return -1;
 461
 462         }
 463
 464         if (i2c_debug & DBG_I2C) {
 465                 int idx;
 466                 for (idx = 0; idx < len; idx++) {
 467                         PDEBUG(DBG_I2C,"wrote %x at address %x", (unsigned char)buf[idx], addr);
 468                 }
 469         }
 470         return len;
 471 }
 472
 473 static int usbvision_i2c_write(struct usb_usbvision *usbvision, unsigned char addr, char *buf,
 474                             short len)
 475 {
 476         char *bufPtr = buf;
 477         int retval;
 478         int wrcount = 0;
 479         int count;
 480         int maxLen = 4;
 481
 482         while (len > 0) {
 483                 count = (len > maxLen) ? maxLen : len;
 484                 retval = usbvision_i2c_write_max4(usbvision, addr, bufPtr, count);
 485                 if (retval > 0) {
 486                         len -= count;
 487                         bufPtr += count;
 488                         wrcount += count;
 489                 } else
 490                         return (retval < 0) ? retval : -EFAULT;
 491         }
 492         return wrcount;
 493 }
 494
 495 static int usbvision_i2c_read(struct usb_usbvision *usbvision, unsigned char addr, char *buf,
 496                            short len)
 497 {
 498         char temp[4];
 499         int retval, i;
 500         int rdcount = 0;
 501         int count;
 502
 503         while (len > 0) {
 504                 count = (len > 3) ? 4 : len;
 505                 retval = usbvision_i2c_read_max4(usbvision, addr, temp, count);
 506                 if (retval > 0) {
 507                         for (i = 0; i < len; i++)
 508                                 buf[rdcount + i] = temp[i];
 509                         len -= count;
 510                         rdcount += count;
 511                 } else
 512                         return (retval < 0) ? retval : -EFAULT;
 513         }
 514         return rdcount;
 515 }
 516
 517 static struct i2c_adapter i2c_adap_template = {
 518         .owner = THIS_MODULE,
 519         .name              = "usbvision",
 520         .id                = I2C_HW_B_BT848, /* FIXME */
 521         .client_register   = attach_inform,
 522         .client_unregister = detach_inform,
 523 #ifdef I2C_ADAP_CLASS_TV_ANALOG
 524         .class             = I2C_ADAP_CLASS_TV_ANALOG,
 525 #else
 526         .class             = I2C_CLASS_TV_ANALOG,
 527 #endif
 528 };
 529
 530 static struct i2c_client i2c_client_template = {
 531         .name           = "usbvision internal",
 532 };
 533
 534 /*
 535  * Overrides for Emacs so that we follow Linus's tabbing style.
 536  * ---------------------------------------------------------------------------
 537  * Local variables:
 538  * c-basic-offset: 8
 539  * End:
 540  */