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

   1 /*
   2  * $Id: saa7134-i2c.c,v 1.10 2005/01/24 17:37:23 kraxel 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 #if 0
 201         i2c_set_attr(dev,attr);
 202         saa_writeb(SAA7134_I2C_DATA, data);
 203 #else
 204         /* have to write both attr + data in one 32bit word */
 205         dword  = saa_readl(SAA7134_I2C_ATTR_STATUS >> 2);
 206         dword &= 0x0f;
 207         dword |= (attr << 6);
 208         dword |= ((__u32)data << 8);
 209         dword |= 0x00 << 16;  /* 100 kHz */
 210 //      dword |= 0x40 << 16;  /* 400 kHz */
 211         dword |= 0xf0 << 24;
 212         saa_writel(SAA7134_I2C_ATTR_STATUS >> 2, dword);
 213 #endif
 214         d2printk(KERN_DEBUG "%s: i2c data => 0x%x\n",dev->name,data);
 215
 216         if (!i2c_is_busy_wait(dev))
 217                 return -EIO;
 218         status = i2c_get_status(dev);
 219         if (i2c_is_error(status))
 220                 return -EIO;
 221         return 0;
 222 }
 223
 224 static inline int i2c_recv_byte(struct saa7134_dev *dev)
 225 {
 226         enum i2c_status status;
 227         unsigned char data;
 228
 229         i2c_set_attr(dev,CONTINUE);
 230         if (!i2c_is_busy_wait(dev))
 231                 return -EIO;
 232         status = i2c_get_status(dev);
 233         if (i2c_is_error(status))
 234                 return -EIO;
 235         data = saa_readb(SAA7134_I2C_DATA);
 236         d2printk(KERN_DEBUG "%s: i2c data <= 0x%x\n",dev->name,data);
 237         return data;
 238 }
 239
 240 static int saa7134_i2c_xfer(struct i2c_adapter *i2c_adap,
 241                             struct i2c_msg *msgs, int num)
 242 {
 243         struct saa7134_dev *dev = i2c_adap->algo_data;
 244         enum i2c_status status;
 245         unsigned char data;
 246         int addr,rc,i,byte;
 247
 248         status = i2c_get_status(dev);
 249         if (!i2c_is_idle(status))
 250                 if (!i2c_reset(dev))
 251                         return -EIO;
 252
 253         d2printk("start xfer\n");
 254         d1printk(KERN_DEBUG "%s: i2c xfer:",dev->name);
 255         for (i = 0; i < num; i++) {
 256                 if (!(msgs[i].flags & I2C_M_NOSTART) || 0 == i) {
 257                         /* send address */
 258                         d2printk("send address\n");
 259                         addr  = msgs[i].addr << 1;
 260                         if (msgs[i].flags & I2C_M_RD)
 261                                 addr |= 1;
 262                         if (i > 0 && msgs[i].flags & I2C_M_RD) {
 263                                 /* workaround for a saa7134 i2c bug
 264                                  * needed to talk to the mt352 demux
 265                                  * thanks to pinnacle for the hint */
 266                                 int quirk = 0xfd;
 267                                 d1printk(" [%02x quirk]",quirk);
 268                                 i2c_send_byte(dev,START,quirk);
 269                                 i2c_recv_byte(dev);
 270                         }
 271                         d1printk(" < %02x", addr);
 272                         rc = i2c_send_byte(dev,START,addr);
 273                         if (rc < 0)
 274                                  goto err;
 275                 }
 276                 if (msgs[i].flags & I2C_M_RD) {
 277                         /* read bytes */
 278                         d2printk("read bytes\n");
 279                         for (byte = 0; byte < msgs[i].len; byte++) {
 280                                 d1printk(" =");
 281                                 rc = i2c_recv_byte(dev);
 282                                 if (rc < 0)
 283                                         goto err;
 284                                 d1printk("%02x", rc);
 285                                 msgs[i].buf[byte] = rc;
 286                         }
 287                 } else {
 288                         /* write bytes */
 289                         d2printk("write bytes\n");
 290                         for (byte = 0; byte < msgs[i].len; byte++) {
 291                                 data = msgs[i].buf[byte];
 292                                 d1printk(" %02x", data);
 293                                 rc = i2c_send_byte(dev,CONTINUE,data);
 294                                 if (rc < 0)
 295                                         goto err;
 296                         }
 297                 }
 298         }
 299         d2printk("xfer done\n");
 300         d1printk(" >");
 301         i2c_set_attr(dev,STOP);
 302         rc = -EIO;
 303         if (!i2c_is_busy_wait(dev))
 304                 goto err;
 305         status = i2c_get_status(dev);
 306         if (i2c_is_error(status))
 307                 goto err;
 308
 309         d1printk("\n");
 310         return num;
 311  err:
 312         if (1 == i2c_debug) {
 313                 status = i2c_get_status(dev);
 314                 printk(" ERROR: %s\n",str_i2c_status[status]);
 315         }
 316         return rc;
 317 }
 318
 319 /* ----------------------------------------------------------- */
 320
 321 static int algo_control(struct i2c_adapter *adapter,
 322                         unsigned int cmd, unsigned long arg)
 323 {
 324         return 0;
 325 }
 326
 327 static u32 functionality(struct i2c_adapter *adap)
 328 {
 329         return I2C_FUNC_SMBUS_EMUL;
 330 }
 331
 332 static int attach_inform(struct i2c_client *client)
 333 {
 334         struct saa7134_dev *dev = client->adapter->algo_data;
 335         int tuner = dev->tuner_type;
 336         int conf  = dev->tda9887_conf;
 337
 338         saa7134_i2c_call_clients(dev,TUNER_SET_TYPE,&tuner);
 339         saa7134_i2c_call_clients(dev,TDA9887_SET_CONFIG,&conf);
 340         return 0;
 341 }
 342
 343 static struct i2c_algorithm saa7134_algo = {
 344         .name          = "saa7134",
 345         .id            = I2C_ALGO_SAA7134,
 346         .master_xfer   = saa7134_i2c_xfer,
 347         .algo_control  = algo_control,
 348         .functionality = functionality,
 349 };
 350
 351 static struct i2c_adapter saa7134_adap_template = {
 352         .owner         = THIS_MODULE,
 353 #ifdef I2C_CLASS_TV_ANALOG
 354         .class         = I2C_CLASS_TV_ANALOG,
 355 #endif
 356         I2C_DEVNAME("saa7134"),
 357         .id            = I2C_ALGO_SAA7134,
 358         .algo          = &saa7134_algo,
 359         .client_register = attach_inform,
 360 };
 361
 362 static struct i2c_client saa7134_client_template = {
 363         I2C_DEVNAME("saa7134 internal"),
 364 };
 365
 366 /* ----------------------------------------------------------- */
 367
 368 static int
 369 saa7134_i2c_eeprom(struct saa7134_dev *dev, unsigned char *eedata, int len)
 370 {
 371         unsigned char buf;
 372         int i,err;
 373
 374         dev->i2c_client.addr = 0xa0 >> 1;
 375         buf = 0;
 376         if (1 != (err = i2c_master_send(&dev->i2c_client,&buf,1))) {
 377                 printk(KERN_INFO "%s: Huh, no eeprom present (err=%d)?\n",
 378                        dev->name,err);
 379                 return -1;
 380         }
 381         if (len != (err = i2c_master_recv(&dev->i2c_client,eedata,len))) {
 382                 printk(KERN_WARNING "%s: i2c eeprom read error (err=%d)\n",
 383                        dev->name,err);
 384                 return -1;
 385         }
 386         for (i = 0; i < len; i++) {
 387                 if (0 == (i % 16))
 388                         printk(KERN_INFO "%s: i2c eeprom %02x:",dev->name,i);
 389                 printk(" %02x",eedata[i]);
 390                 if (15 == (i % 16))
 391                         printk("\n");
 392         }
 393         return 0;
 394 }
 395
 396 static char *i2c_devs[128] = {
 397         [ 0x20      ] = "mpeg encoder (saa6752hs)",
 398         [ 0xa0 >> 1 ] = "eeprom",
 399         [ 0xc0 >> 1 ] = "tuner (analog)",
 400         [ 0x86 >> 1 ] = "tda9887",
 401 };
 402
 403 static void do_i2c_scan(char *name, struct i2c_client *c)
 404 {
 405         unsigned char buf;
 406         int i,rc;
 407
 408         for (i = 0; i < 128; i++) {
 409                 c->addr = i;
 410                 rc = i2c_master_recv(c,&buf,0);
 411                 if (rc < 0)
 412                         continue;
 413                 printk("%s: i2c scan: found device @ 0x%x  [%s]\n",
 414                        name, i << 1, i2c_devs[i] ? i2c_devs[i] : "???");
 415         }
 416 }
 417
 418 void saa7134_i2c_call_clients(struct saa7134_dev *dev,
 419                               unsigned int cmd, void *arg)
 420 {
 421         BUG_ON(NULL == dev->i2c_adap.algo_data);
 422         i2c_clients_command(&dev->i2c_adap, cmd, arg);
 423 }
 424
 425 int saa7134_i2c_register(struct saa7134_dev *dev)
 426 {
 427         dev->i2c_adap = saa7134_adap_template;
 428         dev->i2c_adap.dev.parent = &dev->pci->dev;
 429         strcpy(dev->i2c_adap.name,dev->name);
 430         dev->i2c_adap.algo_data = dev;
 431         i2c_add_adapter(&dev->i2c_adap);
 432
 433         dev->i2c_client = saa7134_client_template;
 434         dev->i2c_client.adapter = &dev->i2c_adap;
 435
 436         saa7134_i2c_eeprom(dev,dev->eedata,sizeof(dev->eedata));
 437         if (i2c_scan)
 438                 do_i2c_scan(dev->name,&dev->i2c_client);
 439         return 0;
 440 }
 441
 442 int saa7134_i2c_unregister(struct saa7134_dev *dev)
 443 {
 444         i2c_del_adapter(&dev->i2c_adap);
 445         return 0;
 446 }
 447
 448 /* ----------------------------------------------------------- */
 449 /*
 450  * Local variables:
 451  * c-basic-offset: 8
 452  * End:
 453  */