drivers/media/video/saa7134/saa7134-i2c.c

   1 /*
   2  *
   3  * device driver for philips saa7134 based TV cards
   4  * i2c interface support
   5  *
   6  * (c) 2001,02 Gerd Knorr <kraxel@bytesex.org> [SuSE Labs]
   7  *
   8  *  This program is free software; you can redistribute it and/or modify
   9  *  it under the terms of the GNU General Public License as published by
  10  *  the Free Software Foundation; either version 2 of the License, or
  11  *  (at your option) any later version.
  12  *
  13  *  This program is distributed in the hope that it will be useful,
  14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  *  GNU General Public License for more details.
  17  *
  18  *  You should have received a copy of the GNU General Public License
  19  *  along with this program; if not, write to the Free Software
  20  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21  */
  22
  23 #include <linux/init.h>
  24 #include <linux/list.h>
  25 #include <linux/module.h>
  26 #include <linux/moduleparam.h>
  27 #include <linux/kernel.h>
  28 #include <linux/slab.h>
  29 #include <linux/delay.h>
  30
  31 #include "saa7134-reg.h"
  32 #include "saa7134.h"
  33
  34 /* ----------------------------------------------------------- */
  35
  36 static unsigned int i2c_debug = 0;
  37 module_param(i2c_debug, int, 0644);
  38 MODULE_PARM_DESC(i2c_debug,"enable debug messages [i2c]");
  39
  40 static unsigned int i2c_scan = 0;
  41 module_param(i2c_scan, int, 0444);
  42 MODULE_PARM_DESC(i2c_scan,"scan i2c bus at insmod time");
  43
  44 #define d1printk if (1 == i2c_debug) printk
  45 #define d2printk if (2 == i2c_debug) printk
  46
  47 #define I2C_WAIT_DELAY  32
  48 #define I2C_WAIT_RETRY  16
  49
  50 /* ----------------------------------------------------------- */
  51
  52 static char *str_i2c_status[] = {
  53         "IDLE", "DONE_STOP", "BUSY", "TO_SCL", "TO_ARB", "DONE_WRITE",
  54         "DONE_READ", "DONE_WRITE_TO", "DONE_READ_TO", "NO_DEVICE",
  55         "NO_ACKN", "BUS_ERR", "ARB_LOST", "SEQ_ERR", "ST_ERR", "SW_ERR"
  56 };
  57
  58 enum i2c_status {
  59         IDLE          = 0,  // no I2C command pending
  60         DONE_STOP     = 1,  // I2C command done and STOP executed
  61         BUSY          = 2,  // executing I2C command
  62         TO_SCL        = 3,  // executing I2C command, time out on clock stretching
  63         TO_ARB        = 4,  // time out on arbitration trial, still trying
  64         DONE_WRITE    = 5,  // I2C command done and awaiting next write command
  65         DONE_READ     = 6,  // I2C command done and awaiting next read command
  66         DONE_WRITE_TO = 7,  // see 5, and time out on status echo
  67         DONE_READ_TO  = 8,  // see 6, and time out on status echo
  68         NO_DEVICE     = 9,  // no acknowledge on device slave address
  69         NO_ACKN       = 10, // no acknowledge after data byte transfer
  70         BUS_ERR       = 11, // bus error
  71         ARB_LOST      = 12, // arbitration lost during transfer
  72         SEQ_ERR       = 13, // erroneous programming sequence
  73         ST_ERR        = 14, // wrong status echoing
  74         SW_ERR        = 15  // software error
  75 };
  76
  77 static char *str_i2c_attr[] = {
  78         "NOP", "STOP", "CONTINUE", "START"
  79 };
  80
  81 enum i2c_attr {
  82         NOP           = 0,  // no operation on I2C bus
  83         STOP          = 1,  // stop condition, no associated byte transfer
  84         CONTINUE      = 2,  // continue with byte transfer
  85         START         = 3   // start condition with byte transfer
  86 };
  87
  88 static inline enum i2c_status i2c_get_status(struct saa7134_dev *dev)
  89 {
  90         enum i2c_status status;
  91
  92         status = saa_readb(SAA7134_I2C_ATTR_STATUS) & 0x0f;
  93         d2printk(KERN_DEBUG "%s: i2c stat <= %s\n",dev->name,
  94                  str_i2c_status[status]);
  95         return status;
  96 }
  97
  98 static inline void i2c_set_status(struct saa7134_dev *dev,
  99                                   enum i2c_status status)
 100 {
 101         d2printk(KERN_DEBUG "%s: i2c stat => %s\n",dev->name,
 102                  str_i2c_status[status]);
 103         saa_andorb(SAA7134_I2C_ATTR_STATUS,0x0f,status);
 104 }
 105
 106 static inline void i2c_set_attr(struct saa7134_dev *dev, enum i2c_attr attr)
 107 {
 108         d2printk(KERN_DEBUG "%s: i2c attr => %s\n",dev->name,
 109                  str_i2c_attr[attr]);
 110         saa_andorb(SAA7134_I2C_ATTR_STATUS,0xc0,attr << 6);
 111 }
 112
 113 static inline int i2c_is_error(enum i2c_status status)
 114 {
 115         switch (status) {
 116         case NO_DEVICE:
 117         case NO_ACKN:
 118         case BUS_ERR:
 119         case ARB_LOST:
 120         case SEQ_ERR:
 121         case ST_ERR:
 122                 return TRUE;
 123         default:
 124                 return FALSE;
 125         }
 126 }
 127
 128 static inline int i2c_is_idle(enum i2c_status status)
 129 {
 130         switch (status) {
 131         case IDLE:
 132         case DONE_STOP:
 133                 return TRUE;
 134         default:
 135                 return FALSE;
 136         }
 137 }
 138
 139 static inline int i2c_is_busy(enum i2c_status status)
 140 {
 141         switch (status) {
 142         case BUSY:
 143                 return TRUE;
 144         default:
 145                 return FALSE;
 146         }
 147 }
 148
 149 static int i2c_is_busy_wait(struct saa7134_dev *dev)
 150 {
 151         enum i2c_status status;
 152         int count;
 153
 154         for (count = 0; count < I2C_WAIT_RETRY; count++) {
 155                 status = i2c_get_status(dev);
 156                 if (!i2c_is_busy(status))
 157                         break;
 158                 saa_wait(I2C_WAIT_DELAY);
 159         }
 160         if (I2C_WAIT_RETRY == count)
 161                 return FALSE;
 162         return TRUE;
 163 }
 164
 165 static int i2c_reset(struct saa7134_dev *dev)
 166 {
 167         enum i2c_status status;
 168         int count;
 169
 170         d2printk(KERN_DEBUG "%s: i2c reset\n",dev->name);
 171         status = i2c_get_status(dev);
 172         if (!i2c_is_error(status))
 173                 return TRUE;
 174         i2c_set_status(dev,status);
 175
 176         for (count = 0; count < I2C_WAIT_RETRY; count++) {
 177                 status = i2c_get_status(dev);
 178                 if (!i2c_is_error(status))
 179                         break;
 180                 udelay(I2C_WAIT_DELAY);
 181         }
 182         if (I2C_WAIT_RETRY == count)
 183                 return FALSE;
 184
 185         if (!i2c_is_idle(status))
 186                 return FALSE;
 187
 188         i2c_set_attr(dev,NOP);
 189         return TRUE;
 190 }
 191
 192 static inline int i2c_send_byte(struct saa7134_dev *dev,
 193                                 enum i2c_attr attr,
 194                                 unsigned char data)
 195 {
 196         enum i2c_status status;
 197         __u32 dword;
 198
 199         /* have to write both attr + data in one 32bit word */
 200         dword  = saa_readl(SAA7134_I2C_ATTR_STATUS >> 2);
 201         dword &= 0x0f;
 202         dword |= (attr << 6);
 203         dword |= ((__u32)data << 8);
 204         dword |= 0x00 << 16;  /* 100 kHz */
 205 //      dword |= 0x40 << 16;  /* 400 kHz */
 206         dword |= 0xf0 << 24;
 207         saa_writel(SAA7134_I2C_ATTR_STATUS >> 2, dword);
 208         d2printk(KERN_DEBUG "%s: i2c data => 0x%x\n",dev->name,data);
 209
 210         if (!i2c_is_busy_wait(dev))
 211                 return -EIO;
 212         status = i2c_get_status(dev);
 213         if (i2c_is_error(status))
 214                 return -EIO;
 215         return 0;
 216 }
 217
 218 static inline int i2c_recv_byte(struct saa7134_dev *dev)
 219 {
 220         enum i2c_status status;
 221         unsigned char data;
 222
 223         i2c_set_attr(dev,CONTINUE);
 224         if (!i2c_is_busy_wait(dev))
 225                 return -EIO;
 226         status = i2c_get_status(dev);
 227         if (i2c_is_error(status))
 228                 return -EIO;
 229         data = saa_readb(SAA7134_I2C_DATA);
 230         d2printk(KERN_DEBUG "%s: i2c data <= 0x%x\n",dev->name,data);
 231         return data;
 232 }
 233
 234 static int saa7134_i2c_xfer(struct i2c_adapter *i2c_adap,
 235                             struct i2c_msg *msgs, int num)
 236 {
 237         struct saa7134_dev *dev = i2c_adap->algo_data;
 238         enum i2c_status status;
 239         unsigned char data;
 240         int addr,rc,i,byte;
 241
 242         status = i2c_get_status(dev);
 243         if (!i2c_is_idle(status))
 244                 if (!i2c_reset(dev))
 245                         return -EIO;
 246
 247         d2printk("start xfer\n");
 248         d1printk(KERN_DEBUG "%s: i2c xfer:",dev->name);
 249         for (i = 0; i < num; i++) {
 250                 if (!(msgs[i].flags & I2C_M_NOSTART) || 0 == i) {
 251                         /* send address */
 252                         d2printk("send address\n");
 253                         addr  = msgs[i].addr << 1;
 254                         if (msgs[i].flags & I2C_M_RD)
 255                                 addr |= 1;
 256                         if (i > 0 && msgs[i].flags & I2C_M_RD) {
 257                                 /* workaround for a saa7134 i2c bug
 258                                  * needed to talk to the mt352 demux
 259                                  * thanks to pinnacle for the hint */
 260                                 int quirk = 0xfd;
 261                                 d1printk(" [%02x quirk]",quirk);
 262                                 i2c_send_byte(dev,START,quirk);
 263                                 i2c_recv_byte(dev);
 264                         }
 265                         d1printk(" < %02x", addr);
 266                         rc = i2c_send_byte(dev,START,addr);
 267                         if (rc < 0)
 268                                  goto err;
 269                 }
 270                 if (msgs[i].flags & I2C_M_RD) {
 271                         /* read bytes */
 272                         d2printk("read bytes\n");
 273                         for (byte = 0; byte < msgs[i].len; byte++) {
 274                                 d1printk(" =");
 275                                 rc = i2c_recv_byte(dev);
 276                                 if (rc < 0)
 277                                         goto err;
 278                                 d1printk("%02x", rc);
 279                                 msgs[i].buf[byte] = rc;
 280                         }
 281                 } else {
 282                         /* write bytes */
 283                         d2printk("write bytes\n");
 284                         for (byte = 0; byte < msgs[i].len; byte++) {
 285                                 data = msgs[i].buf[byte];
 286                                 d1printk(" %02x", data);
 287                                 rc = i2c_send_byte(dev,CONTINUE,data);
 288                                 if (rc < 0)
 289                                         goto err;
 290                         }
 291                 }
 292         }
 293         d2printk("xfer done\n");
 294         d1printk(" >");
 295         i2c_set_attr(dev,STOP);
 296         rc = -EIO;
 297         if (!i2c_is_busy_wait(dev))
 298                 goto err;
 299         status = i2c_get_status(dev);
 300         if (i2c_is_error(status))
 301                 goto err;
 302         /* ensure that the bus is idle for at least one bit slot */
 303         msleep(1);
 304
 305         d1printk("\n");
 306         return num;
 307  err:
 308         if (1 == i2c_debug) {
 309                 status = i2c_get_status(dev);
 310                 printk(" ERROR: %s\n",str_i2c_status[status]);
 311         }
 312         return rc;
 313 }
 314
 315 /* ----------------------------------------------------------- */
 316
 317 static int algo_control(struct i2c_adapter *adapter,
 318                         unsigned int cmd, unsigned long arg)
 319 {
 320         return 0;
 321 }
 322
 323 static u32 functionality(struct i2c_adapter *adap)
 324 {
 325         return I2C_FUNC_SMBUS_EMUL;
 326 }
 327
 328 static int attach_inform(struct i2c_client *client)
 329 {
 330         struct saa7134_dev *dev = client->adapter->algo_data;
 331         int tuner = dev->tuner_type;
 332         int conf  = dev->tda9887_conf;
 333         struct tuner_setup tun_setup;
 334
 335         d1printk( "%s i2c attach [addr=0x%x,client=%s]\n",
 336                  client->driver->name, client->addr, client->name);
 337
 338         if (!client->driver->command)
 339                 return 0;
 340
 341         if (saa7134_boards[dev->board].radio_type != UNSET) {
 342
 343                 tun_setup.type = saa7134_boards[dev->board].radio_type;
 344                 tun_setup.addr = saa7134_boards[dev->board].radio_addr;
 345
 346                 if ((tun_setup.addr == ADDR_UNSET) || (tun_setup.addr == client->addr)) {
 347                         tun_setup.mode_mask = T_RADIO;
 348
 349                         client->driver->command(client, TUNER_SET_TYPE_ADDR, &tun_setup);
 350                 }
 351         }
 352
 353         if (tuner != UNSET) {
 354
 355                 tun_setup.type = tuner;
 356                 tun_setup.addr = saa7134_boards[dev->board].tuner_addr;
 357
 358                 if ((tun_setup.addr == ADDR_UNSET)||(tun_setup.addr == client->addr)) {
 359
 360                         tun_setup.mode_mask = T_ANALOG_TV;
 361
 362                         client->driver->command(client,TUNER_SET_TYPE_ADDR, &tun_setup);
 363                 }
 364         }
 365
 366         client->driver->command(client, TDA9887_SET_CONFIG, &conf);
 367
 368         return 0;
 369 }
 370
 371 static struct i2c_algorithm saa7134_algo = {
 372         .master_xfer   = saa7134_i2c_xfer,
 373         .algo_control  = algo_control,
 374         .functionality = functionality,
 375 };
 376
 377 static struct i2c_adapter saa7134_adap_template = {
 378         .owner         = THIS_MODULE,
 379 #ifdef I2C_CLASS_TV_ANALOG
 380         .class         = I2C_CLASS_TV_ANALOG,
 381 #endif
 382         .name          = "saa7134",
 383         .id            = I2C_HW_SAA7134,
 384         .algo          = &saa7134_algo,
 385         .client_register = attach_inform,
 386 };
 387
 388 static struct i2c_client saa7134_client_template = {
 389         .name   = "saa7134 internal",
 390 };
 391
 392 /* ----------------------------------------------------------- */
 393
 394 static int
 395 saa7134_i2c_eeprom(struct saa7134_dev *dev, unsigned char *eedata, int len)
 396 {
 397         unsigned char buf;
 398         int i,err;
 399
 400         dev->i2c_client.addr = 0xa0 >> 1;
 401         buf = 0;
 402         if (1 != (err = i2c_master_send(&dev->i2c_client,&buf,1))) {
 403                 printk(KERN_INFO "%s: Huh, no eeprom present (err=%d)?\n",
 404                        dev->name,err);
 405                 return -1;
 406         }
 407         if (len != (err = i2c_master_recv(&dev->i2c_client,eedata,len))) {
 408                 printk(KERN_WARNING "%s: i2c eeprom read error (err=%d)\n",
 409                        dev->name,err);
 410                 return -1;
 411         }
 412         for (i = 0; i < len; i++) {
 413                 if (0 == (i % 16))
 414                         printk(KERN_INFO "%s: i2c eeprom %02x:",dev->name,i);
 415                 printk(" %02x",eedata[i]);
 416                 if (15 == (i % 16))
 417                         printk("\n");
 418         }
 419         return 0;
 420 }
 421
 422 static char *i2c_devs[128] = {
 423         [ 0x20      ] = "mpeg encoder (saa6752hs)",
 424         [ 0xa0 >> 1 ] = "eeprom",
 425         [ 0xc0 >> 1 ] = "tuner (analog)",
 426         [ 0x86 >> 1 ] = "tda9887",
 427 };
 428
 429 static void do_i2c_scan(char *name, struct i2c_client *c)
 430 {
 431         unsigned char buf;
 432         int i,rc;
 433
 434         for (i = 0; i < 128; i++) {
 435                 c->addr = i;
 436                 rc = i2c_master_recv(c,&buf,0);
 437                 if (rc < 0)
 438                         continue;
 439                 printk("%s: i2c scan: found device @ 0x%x  [%s]\n",
 440                        name, i << 1, i2c_devs[i] ? i2c_devs[i] : "???");
 441         }
 442 }
 443
 444 void saa7134_i2c_call_clients(struct saa7134_dev *dev,
 445                               unsigned int cmd, void *arg)
 446 {
 447         BUG_ON(NULL == dev->i2c_adap.algo_data);
 448         i2c_clients_command(&dev->i2c_adap, cmd, arg);
 449 }
 450
 451 int saa7134_i2c_register(struct saa7134_dev *dev)
 452 {
 453         dev->i2c_adap = saa7134_adap_template;
 454         dev->i2c_adap.dev.parent = &dev->pci->dev;
 455         strcpy(dev->i2c_adap.name,dev->name);
 456         dev->i2c_adap.algo_data = dev;
 457         i2c_add_adapter(&dev->i2c_adap);
 458
 459         dev->i2c_client = saa7134_client_template;
 460         dev->i2c_client.adapter = &dev->i2c_adap;
 461
 462         saa7134_i2c_eeprom(dev,dev->eedata,sizeof(dev->eedata));
 463         if (i2c_scan)
 464                 do_i2c_scan(dev->name,&dev->i2c_client);
 465         return 0;
 466 }
 467
 468 int saa7134_i2c_unregister(struct saa7134_dev *dev)
 469 {
 470         i2c_del_adapter(&dev->i2c_adap);
 471         return 0;
 472 }
 473
 474 /* ----------------------------------------------------------- */
 475 /*
 476  * Local variables:
 477  * c-basic-offset: 8
 478  * End:
 479  */