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

   1 /*
   2  * $Id: saa7134-i2c.c,v 1.22 2005/07/22 04:09:41 mkrufky Exp $
   3  *
   4  * device driver for philips saa7134 based TV cards
   5  * i2c interface support
   6  *
   7  * (c) 2001,02 Gerd Knorr <kraxel@bytesex.org> [SuSE Labs]
   8  *
   9  *  This program is free software; you can redistribute it and/or modify
  10  *  it under the terms of the GNU General Public License as published by
  11  *  the Free Software Foundation; either version 2 of the License, or
  12  *  (at your option) any later version.
  13  *
  14  *  This program is distributed in the hope that it will be useful,
  15  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  *  GNU General Public License for more details.
  18  *
  19  *  You should have received a copy of the GNU General Public License
  20  *  along with this program; if not, write to the Free Software
  21  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  22  */
  23
  24 #include <linux/init.h>
  25 #include <linux/list.h>
  26 #include <linux/module.h>
  27 #include <linux/moduleparam.h>
  28 #include <linux/kernel.h>
  29 #include <linux/slab.h>
  30 #include <linux/delay.h>
  31
  32 #include "saa7134-reg.h"
  33 #include "saa7134.h"
  34
  35 /* ----------------------------------------------------------- */
  36
  37 static unsigned int i2c_debug = 0;
  38 module_param(i2c_debug, int, 0644);
  39 MODULE_PARM_DESC(i2c_debug,"enable debug messages [i2c]");
  40
  41 static unsigned int i2c_scan = 0;
  42 module_param(i2c_scan, int, 0444);
  43 MODULE_PARM_DESC(i2c_scan,"scan i2c bus at insmod time");
  44
  45 #define d1printk if (1 == i2c_debug) printk
  46 #define d2printk if (2 == i2c_debug) printk
  47
  48 #define I2C_WAIT_DELAY  32
  49 #define I2C_WAIT_RETRY  16
  50
  51 /* ----------------------------------------------------------- */
  52
  53 static char *str_i2c_status[] = {
  54         "IDLE", "DONE_STOP", "BUSY", "TO_SCL", "TO_ARB", "DONE_WRITE",
  55         "DONE_READ", "DONE_WRITE_TO", "DONE_READ_TO", "NO_DEVICE",
  56         "NO_ACKN", "BUS_ERR", "ARB_LOST", "SEQ_ERR", "ST_ERR", "SW_ERR"
  57 };
  58
  59 enum i2c_status {
  60         IDLE          = 0,  // no I2C command pending
  61         DONE_STOP     = 1,  // I2C command done and STOP executed
  62         BUSY          = 2,  // executing I2C command
  63         TO_SCL        = 3,  // executing I2C command, time out on clock stretching
  64         TO_ARB        = 4,  // time out on arbitration trial, still trying
  65         DONE_WRITE    = 5,  // I2C command done and awaiting next write command
  66         DONE_READ     = 6,  // I2C command done and awaiting next read command
  67         DONE_WRITE_TO = 7,  // see 5, and time out on status echo
  68         DONE_READ_TO  = 8,  // see 6, and time out on status echo
  69         NO_DEVICE     = 9,  // no acknowledge on device slave address
  70         NO_ACKN       = 10, // no acknowledge after data byte transfer
  71         BUS_ERR       = 11, // bus error
  72         ARB_LOST      = 12, // arbitration lost during transfer
  73         SEQ_ERR       = 13, // erroneous programming sequence
  74         ST_ERR        = 14, // wrong status echoing
  75         SW_ERR        = 15  // software error
  76 };
  77
  78 static char *str_i2c_attr[] = {
  79         "NOP", "STOP", "CONTINUE", "START"
  80 };
  81
  82 enum i2c_attr {
  83         NOP           = 0,  // no operation on I2C bus
  84         STOP          = 1,  // stop condition, no associated byte transfer
  85         CONTINUE      = 2,  // continue with byte transfer
  86         START         = 3   // start condition with byte transfer
  87 };
  88
  89 static inline enum i2c_status i2c_get_status(struct saa7134_dev *dev)
  90 {
  91         enum i2c_status status;
  92
  93         status = saa_readb(SAA7134_I2C_ATTR_STATUS) & 0x0f;
  94         d2printk(KERN_DEBUG "%s: i2c stat <= %s\n",dev->name,
  95                  str_i2c_status[status]);
  96         return status;
  97 }
  98
  99 static inline void i2c_set_status(struct saa7134_dev *dev,
 100                                   enum i2c_status status)
 101 {
 102         d2printk(KERN_DEBUG "%s: i2c stat => %s\n",dev->name,
 103                  str_i2c_status[status]);
 104         saa_andorb(SAA7134_I2C_ATTR_STATUS,0x0f,status);
 105 }
 106
 107 static inline void i2c_set_attr(struct saa7134_dev *dev, enum i2c_attr attr)
 108 {
 109         d2printk(KERN_DEBUG "%s: i2c attr => %s\n",dev->name,
 110                  str_i2c_attr[attr]);
 111         saa_andorb(SAA7134_I2C_ATTR_STATUS,0xc0,attr << 6);
 112 }
 113
 114 static inline int i2c_is_error(enum i2c_status status)
 115 {
 116         switch (status) {
 117         case NO_DEVICE:
 118         case NO_ACKN:
 119         case BUS_ERR:
 120         case ARB_LOST:
 121         case SEQ_ERR:
 122         case ST_ERR:
 123                 return TRUE;
 124         default:
 125                 return FALSE;
 126         }
 127 }
 128
 129 static inline int i2c_is_idle(enum i2c_status status)
 130 {
 131         switch (status) {
 132         case IDLE:
 133         case DONE_STOP:
 134                 return TRUE;
 135         default:
 136                 return FALSE;
 137         }
 138 }
 139
 140 static inline int i2c_is_busy(enum i2c_status status)
 141 {
 142         switch (status) {
 143         case BUSY:
 144                 return TRUE;
 145         default:
 146                 return FALSE;
 147         }
 148 }
 149
 150 static int i2c_is_busy_wait(struct saa7134_dev *dev)
 151 {
 152         enum i2c_status status;
 153         int count;
 154
 155         for (count = 0; count < I2C_WAIT_RETRY; count++) {
 156                 status = i2c_get_status(dev);
 157                 if (!i2c_is_busy(status))
 158                         break;
 159                 saa_wait(I2C_WAIT_DELAY);
 160         }
 161         if (I2C_WAIT_RETRY == count)
 162                 return FALSE;
 163         return TRUE;
 164 }
 165
 166 static int i2c_reset(struct saa7134_dev *dev)
 167 {
 168         enum i2c_status status;
 169         int count;
 170
 171         d2printk(KERN_DEBUG "%s: i2c reset\n",dev->name);
 172         status = i2c_get_status(dev);
 173         if (!i2c_is_error(status))
 174                 return TRUE;
 175         i2c_set_status(dev,status);
 176
 177         for (count = 0; count < I2C_WAIT_RETRY; count++) {
 178                 status = i2c_get_status(dev);
 179                 if (!i2c_is_error(status))
 180                         break;
 181                 udelay(I2C_WAIT_DELAY);
 182         }
 183         if (I2C_WAIT_RETRY == count)
 184                 return FALSE;
 185
 186         if (!i2c_is_idle(status))
 187                 return FALSE;
 188
 189         i2c_set_attr(dev,NOP);
 190         return TRUE;
 191 }
 192
 193 static inline int i2c_send_byte(struct saa7134_dev *dev,
 194                                 enum i2c_attr attr,
 195                                 unsigned char data)
 196 {
 197         enum i2c_status status;
 198         __u32 dword;
 199
 200         /* have to write both attr + data in one 32bit word */
 201         dword  = saa_readl(SAA7134_I2C_ATTR_STATUS >> 2);
 202         dword &= 0x0f;
 203         dword |= (attr << 6);
 204         dword |= ((__u32)data << 8);
 205         dword |= 0x00 << 16;  /* 100 kHz */
 206 //      dword |= 0x40 << 16;  /* 400 kHz */
 207         dword |= 0xf0 << 24;
 208         saa_writel(SAA7134_I2C_ATTR_STATUS >> 2, dword);
 209         d2printk(KERN_DEBUG "%s: i2c data => 0x%x\n",dev->name,data);
 210
 211         if (!i2c_is_busy_wait(dev))
 212                 return -EIO;
 213         status = i2c_get_status(dev);
 214         if (i2c_is_error(status))
 215                 return -EIO;
 216         return 0;
 217 }
 218
 219 static inline int i2c_recv_byte(struct saa7134_dev *dev)
 220 {
 221         enum i2c_status status;
 222         unsigned char data;
 223
 224         i2c_set_attr(dev,CONTINUE);
 225         if (!i2c_is_busy_wait(dev))
 226                 return -EIO;
 227         status = i2c_get_status(dev);
 228         if (i2c_is_error(status))
 229                 return -EIO;
 230         data = saa_readb(SAA7134_I2C_DATA);
 231         d2printk(KERN_DEBUG "%s: i2c data <= 0x%x\n",dev->name,data);
 232         return data;
 233 }
 234
 235 static int saa7134_i2c_xfer(struct i2c_adapter *i2c_adap,
 236                             struct i2c_msg *msgs, int num)
 237 {
 238         struct saa7134_dev *dev = i2c_adap->algo_data;
 239         enum i2c_status status;
 240         unsigned char data;
 241         int addr,rc,i,byte;
 242
 243         status = i2c_get_status(dev);
 244         if (!i2c_is_idle(status))
 245                 if (!i2c_reset(dev))
 246                         return -EIO;
 247
 248         d2printk("start xfer\n");
 249         d1printk(KERN_DEBUG "%s: i2c xfer:",dev->name);
 250         for (i = 0; i < num; i++) {
 251                 if (!(msgs[i].flags & I2C_M_NOSTART) || 0 == i) {
 252                         /* send address */
 253                         d2printk("send address\n");
 254                         addr  = msgs[i].addr << 1;
 255                         if (msgs[i].flags & I2C_M_RD)
 256                                 addr |= 1;
 257                         if (i > 0 && msgs[i].flags & I2C_M_RD) {
 258                                 /* workaround for a saa7134 i2c bug
 259                                  * needed to talk to the mt352 demux
 260                                  * thanks to pinnacle for the hint */
 261                                 int quirk = 0xfd;
 262                                 d1printk(" [%02x quirk]",quirk);
 263                                 i2c_send_byte(dev,START,quirk);
 264                                 i2c_recv_byte(dev);
 265                         }
 266                         d1printk(" < %02x", addr);
 267                         rc = i2c_send_byte(dev,START,addr);
 268                         if (rc < 0)
 269                                  goto err;
 270                 }
 271                 if (msgs[i].flags & I2C_M_RD) {
 272                         /* read bytes */
 273                         d2printk("read bytes\n");
 274                         for (byte = 0; byte < msgs[i].len; byte++) {
 275                                 d1printk(" =");
 276                                 rc = i2c_recv_byte(dev);
 277                                 if (rc < 0)
 278                                         goto err;
 279                                 d1printk("%02x", rc);
 280                                 msgs[i].buf[byte] = rc;
 281                         }
 282                 } else {
 283                         /* write bytes */
 284                         d2printk("write bytes\n");
 285                         for (byte = 0; byte < msgs[i].len; byte++) {
 286                                 data = msgs[i].buf[byte];
 287                                 d1printk(" %02x", data);
 288                                 rc = i2c_send_byte(dev,CONTINUE,data);
 289                                 if (rc < 0)
 290                                         goto err;
 291                         }
 292                 }
 293         }
 294         d2printk("xfer done\n");
 295         d1printk(" >");
 296         i2c_set_attr(dev,STOP);
 297         rc = -EIO;
 298         if (!i2c_is_busy_wait(dev))
 299                 goto err;
 300         status = i2c_get_status(dev);
 301         if (i2c_is_error(status))
 302                 goto err;
 303         /* ensure that the bus is idle for at least one bit slot */
 304         msleep(1);
 305
 306         d1printk("\n");
 307         return num;
 308  err:
 309         if (1 == i2c_debug) {
 310                 status = i2c_get_status(dev);
 311                 printk(" ERROR: %s\n",str_i2c_status[status]);
 312         }
 313         return rc;
 314 }
 315
 316 /* ----------------------------------------------------------- */
 317
 318 static int algo_control(struct i2c_adapter *adapter,
 319                         unsigned int cmd, unsigned long arg)
 320 {
 321         return 0;
 322 }
 323
 324 static u32 functionality(struct i2c_adapter *adap)
 325 {
 326         return I2C_FUNC_SMBUS_EMUL;
 327 }
 328
 329 static int attach_inform(struct i2c_client *client)
 330 {
 331         struct saa7134_dev *dev = client->adapter->algo_data;
 332         int tuner = dev->tuner_type;
 333         int conf  = dev->tda9887_conf;
 334         struct tuner_setup tun_setup;
 335
 336         d1printk( "%s i2c attach [addr=0x%x,client=%s]\n",
 337                  client->driver->name, client->addr, client->name);
 338
 339         if (!client->driver->command)
 340                 return 0;
 341
 342         if (saa7134_boards[dev->board].radio_type != UNSET) {
 343
 344                 tun_setup.type = saa7134_boards[dev->board].radio_type;
 345                 tun_setup.addr = saa7134_boards[dev->board].radio_addr;
 346
 347                 if ((tun_setup.addr == ADDR_UNSET) || (tun_setup.addr == client->addr)) {
 348                         tun_setup.mode_mask = T_RADIO;
 349
 350                         client->driver->command(client, TUNER_SET_TYPE_ADDR, &tun_setup);
 351                 }
 352         }
 353
 354         if (tuner != UNSET) {
 355
 356                 tun_setup.type = tuner;
 357                 tun_setup.addr = saa7134_boards[dev->board].tuner_addr;
 358
 359                 if ((tun_setup.addr == ADDR_UNSET)||(tun_setup.addr == client->addr)) {
 360
 361                         tun_setup.mode_mask = T_ANALOG_TV;
 362
 363                         client->driver->command(client,TUNER_SET_TYPE_ADDR, &tun_setup);
 364                 }
 365         }
 366
 367         client->driver->command(client, TDA9887_SET_CONFIG, &conf);
 368
 369         return 0;
 370 }
 371
 372 static struct i2c_algorithm saa7134_algo = {
 373         .master_xfer   = saa7134_i2c_xfer,
 374         .algo_control  = algo_control,
 375         .functionality = functionality,
 376 };
 377
 378 static struct i2c_adapter saa7134_adap_template = {
 379         .owner         = THIS_MODULE,
 380 #ifdef I2C_CLASS_TV_ANALOG
 381         .class         = I2C_CLASS_TV_ANALOG,
 382 #endif
 383         .name          = "saa7134",
 384         .id            = I2C_HW_SAA7134,
 385         .algo          = &saa7134_algo,
 386         .client_register = attach_inform,
 387 };
 388
 389 static struct i2c_client saa7134_client_template = {
 390         .name   = "saa7134 internal",
 391 };
 392
 393 /* ----------------------------------------------------------- */
 394
 395 static int
 396 saa7134_i2c_eeprom(struct saa7134_dev *dev, unsigned char *eedata, int len)
 397 {
 398         unsigned char buf;
 399         int i,err;
 400
 401         dev->i2c_client.addr = 0xa0 >> 1;
 402         buf = 0;
 403         if (1 != (err = i2c_master_send(&dev->i2c_client,&buf,1))) {
 404                 printk(KERN_INFO "%s: Huh, no eeprom present (err=%d)?\n",
 405                        dev->name,err);
 406                 return -1;
 407         }
 408         if (len != (err = i2c_master_recv(&dev->i2c_client,eedata,len))) {
 409                 printk(KERN_WARNING "%s: i2c eeprom read error (err=%d)\n",
 410                        dev->name,err);
 411                 return -1;
 412         }
 413         for (i = 0; i < len; i++) {
 414                 if (0 == (i % 16))
 415                         printk(KERN_INFO "%s: i2c eeprom %02x:",dev->name,i);
 416                 printk(" %02x",eedata[i]);
 417                 if (15 == (i % 16))
 418                         printk("\n");
 419         }
 420         return 0;
 421 }
 422
 423 static char *i2c_devs[128] = {
 424         [ 0x20      ] = "mpeg encoder (saa6752hs)",
 425         [ 0xa0 >> 1 ] = "eeprom",
 426         [ 0xc0 >> 1 ] = "tuner (analog)",
 427         [ 0x86 >> 1 ] = "tda9887",
 428 };
 429
 430 static void do_i2c_scan(char *name, struct i2c_client *c)
 431 {
 432         unsigned char buf;
 433         int i,rc;
 434
 435         for (i = 0; i < 128; i++) {
 436                 c->addr = i;
 437                 rc = i2c_master_recv(c,&buf,0);
 438                 if (rc < 0)
 439                         continue;
 440                 printk("%s: i2c scan: found device @ 0x%x  [%s]\n",
 441                        name, i << 1, i2c_devs[i] ? i2c_devs[i] : "???");
 442         }
 443 }
 444
 445 void saa7134_i2c_call_clients(struct saa7134_dev *dev,
 446                               unsigned int cmd, void *arg)
 447 {
 448         BUG_ON(NULL == dev->i2c_adap.algo_data);
 449         i2c_clients_command(&dev->i2c_adap, cmd, arg);
 450 }
 451
 452 int saa7134_i2c_register(struct saa7134_dev *dev)
 453 {
 454         dev->i2c_adap = saa7134_adap_template;
 455         dev->i2c_adap.dev.parent = &dev->pci->dev;
 456         strcpy(dev->i2c_adap.name,dev->name);
 457         dev->i2c_adap.algo_data = dev;
 458         i2c_add_adapter(&dev->i2c_adap);
 459
 460         dev->i2c_client = saa7134_client_template;
 461         dev->i2c_client.adapter = &dev->i2c_adap;
 462
 463         saa7134_i2c_eeprom(dev,dev->eedata,sizeof(dev->eedata));
 464         if (i2c_scan)
 465                 do_i2c_scan(dev->name,&dev->i2c_client);
 466         return 0;
 467 }
 468
 469 int saa7134_i2c_unregister(struct saa7134_dev *dev)
 470 {
 471         i2c_del_adapter(&dev->i2c_adap);
 472         return 0;
 473 }
 474
 475 /* ----------------------------------------------------------- */
 476 /*
 477  * Local variables:
 478  * c-basic-offset: 8
 479  * End:
 480  */