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

   1 /*
   2  * $Id: saa7134-i2c.c,v 1.7 2004/11/07 13:17:15 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/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 #if 0
 200         i2c_set_attr(dev,attr);
 201         saa_writeb(SAA7134_I2C_DATA, data);
 202 #else
 203         /* have to write both attr + data in one 32bit word */
 204         dword  = saa_readl(SAA7134_I2C_ATTR_STATUS >> 2);
 205         dword &= 0x0f;
 206         dword |= (attr << 6);
 207         dword |= ((__u32)data << 8);
 208         dword |= 0x00 << 16;
 209         dword |= 0xf0 << 24;
 210         saa_writel(SAA7134_I2C_ATTR_STATUS >> 2, dword);
 211 #endif
 212         d2printk(KERN_DEBUG "%s: i2c data => 0x%x\n",dev->name,data);
 213
 214         if (!i2c_is_busy_wait(dev))
 215                 return -EIO;
 216         status = i2c_get_status(dev);
 217         if (i2c_is_error(status))
 218                 return -EIO;
 219         return 0;
 220 }
 221
 222 static inline int i2c_recv_byte(struct saa7134_dev *dev)
 223 {
 224         enum i2c_status status;
 225         unsigned char data;
 226
 227         i2c_set_attr(dev,CONTINUE);
 228         if (!i2c_is_busy_wait(dev))
 229                 return -EIO;
 230         status = i2c_get_status(dev);
 231         if (i2c_is_error(status))
 232                 return -EIO;
 233         data = saa_readb(SAA7134_I2C_DATA);
 234         d2printk(KERN_DEBUG "%s: i2c data <= 0x%x\n",dev->name,data);
 235         return data;
 236 }
 237
 238 static int saa7134_i2c_xfer(struct i2c_adapter *i2c_adap,
 239                             struct i2c_msg msgs[], int num)
 240 {
 241         struct saa7134_dev *dev = i2c_adap->algo_data;
 242         enum i2c_status status;
 243         unsigned char data;
 244         int addr,rc,i,byte;
 245
 246         status = i2c_get_status(dev);
 247         if (!i2c_is_idle(status))
 248                 if (!i2c_reset(dev))
 249                         return -EIO;
 250
 251         d1printk(KERN_DEBUG "%s: i2c xfer:",dev->name);
 252         for (i = 0; i < num; i++) {
 253                 if (!(msgs[i].flags & I2C_M_NOSTART) || 0 == i) {
 254                         /* send address */
 255                         addr  = msgs[i].addr << 1;
 256                         if (msgs[i].flags & I2C_M_RD)
 257                                 addr |= 1;
 258                         d1printk(" < %02x", addr);
 259                         rc = i2c_send_byte(dev,START,addr);
 260                         if (rc < 0)
 261                                  goto err;
 262                 }
 263                 if (msgs[i].flags & I2C_M_RD) {
 264                         /* read bytes */
 265                         for (byte = 0; byte < msgs[i].len; byte++) {
 266                                 d1printk(" =");
 267                                 rc = i2c_recv_byte(dev);
 268                                 if (rc < 0)
 269                                         goto err;
 270                                 d1printk("%02x", rc);
 271                                 msgs[i].buf[byte] = rc;
 272                         }
 273                 } else {
 274                         /* write bytes */
 275                         for (byte = 0; byte < msgs[i].len; byte++) {
 276                                 data = msgs[i].buf[byte];
 277                                 d1printk(" %02x", data);
 278                                 rc = i2c_send_byte(dev,CONTINUE,data);
 279                                 if (rc < 0)
 280                                         goto err;
 281                         }
 282                 }
 283         }
 284         d1printk(" >");
 285         i2c_set_attr(dev,STOP);
 286         rc = -EIO;
 287         if (!i2c_is_busy_wait(dev))
 288                 goto err;
 289         status = i2c_get_status(dev);
 290         if (i2c_is_error(status))
 291                 goto err;
 292
 293         d1printk("\n");
 294         return num;
 295  err:
 296         if (1 == i2c_debug) {
 297                 status = i2c_get_status(dev);
 298                 printk(" ERROR: %s\n",str_i2c_status[status]);
 299         }
 300         return rc;
 301 }
 302
 303 /* ----------------------------------------------------------- */
 304
 305 static int algo_control(struct i2c_adapter *adapter,
 306                         unsigned int cmd, unsigned long arg)
 307 {
 308         return 0;
 309 }
 310
 311 static u32 functionality(struct i2c_adapter *adap)
 312 {
 313         return I2C_FUNC_SMBUS_EMUL;
 314 }
 315
 316 #ifndef I2C_PEC
 317 static void inc_use(struct i2c_adapter *adap)
 318 {
 319         MOD_INC_USE_COUNT;
 320 }
 321
 322 static void dec_use(struct i2c_adapter *adap)
 323 {
 324         MOD_DEC_USE_COUNT;
 325 }
 326 #endif
 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
 334         saa7134_i2c_call_clients(dev,TUNER_SET_TYPE,&tuner);
 335         saa7134_i2c_call_clients(dev,TDA9887_SET_CONFIG,&conf);
 336         return 0;
 337 }
 338
 339 static struct i2c_algorithm saa7134_algo = {
 340         .name          = "saa7134",
 341         .id            = I2C_ALGO_SAA7134,
 342         .master_xfer   = saa7134_i2c_xfer,
 343         .algo_control  = algo_control,
 344         .functionality = functionality,
 345 };
 346
 347 static struct i2c_adapter saa7134_adap_template = {
 348 #ifdef I2C_PEC
 349         .owner         = THIS_MODULE,
 350 #else
 351         .inc_use       = inc_use,
 352         .dec_use       = dec_use,
 353 #endif
 354 #ifdef I2C_CLASS_TV_ANALOG
 355         .class         = I2C_CLASS_TV_ANALOG,
 356 #endif
 357         I2C_DEVNAME("saa7134"),
 358         .id            = I2C_ALGO_SAA7134,
 359         .algo          = &saa7134_algo,
 360         .client_register = attach_inform,
 361 };
 362
 363 static struct i2c_client saa7134_client_template = {
 364         I2C_DEVNAME("saa7134 internal"),
 365         .id        = -1,
 366 };
 367
 368 /* ----------------------------------------------------------- */
 369
 370 static int
 371 saa7134_i2c_eeprom(struct saa7134_dev *dev, unsigned char *eedata, int len)
 372 {
 373         unsigned char buf;
 374         int i,err;
 375
 376         dev->i2c_client.addr = 0xa0 >> 1;
 377         buf = 0;
 378         if (1 != (err = i2c_master_send(&dev->i2c_client,&buf,1))) {
 379                 printk(KERN_INFO "%s: Huh, no eeprom present (err=%d)?\n",
 380                        dev->name,err);
 381                 return -1;
 382         }
 383         if (len != (err = i2c_master_recv(&dev->i2c_client,eedata,len))) {
 384                 printk(KERN_WARNING "%s: i2c eeprom read error (err=%d)\n",
 385                        dev->name,err);
 386                 return -1;
 387         }
 388         for (i = 0; i < len; i++) {
 389                 if (0 == (i % 16))
 390                         printk(KERN_INFO "%s: i2c eeprom %02x:",dev->name,i);
 391                 printk(" %02x",eedata[i]);
 392                 if (15 == (i % 16))
 393                         printk("\n");
 394         }
 395         return 0;
 396 }
 397
 398 static char *i2c_devs[128] = {
 399         [ 0x20      ] = "mpeg encoder (saa6752hs)",
 400         [ 0xa0 >> 1 ] = "eeprom",
 401         [ 0xc0 >> 1 ] = "tuner (analog)",
 402         [ 0x86 >> 1 ] = "tda9887",
 403 };
 404
 405 static void do_i2c_scan(char *name, struct i2c_client *c)
 406 {
 407         unsigned char buf;
 408         int i,rc;
 409
 410         for (i = 0; i < 128; i++) {
 411                 c->addr = i;
 412                 rc = i2c_master_recv(c,&buf,0);
 413                 if (rc < 0)
 414                         continue;
 415                 printk("%s: i2c scan: found device @ 0x%x  [%s]\n",
 416                        name, i << 1, i2c_devs[i] ? i2c_devs[i] : "???");
 417         }
 418 }
 419
 420 void saa7134_i2c_call_clients(struct saa7134_dev *dev,
 421                               unsigned int cmd, void *arg)
 422 {
 423         BUG_ON(NULL == dev->i2c_adap.algo_data);
 424         i2c_clients_command(&dev->i2c_adap, cmd, arg);
 425 }
 426
 427 int saa7134_i2c_register(struct saa7134_dev *dev)
 428 {
 429         dev->i2c_adap = saa7134_adap_template;
 430         dev->i2c_adap.dev.parent = &dev->pci->dev;
 431         strcpy(dev->i2c_adap.name,dev->name);
 432         dev->i2c_adap.algo_data = dev;
 433         i2c_add_adapter(&dev->i2c_adap);
 434
 435         dev->i2c_client = saa7134_client_template;
 436         dev->i2c_client.adapter = &dev->i2c_adap;
 437
 438         saa7134_i2c_eeprom(dev,dev->eedata,sizeof(dev->eedata));
 439         if (i2c_scan)
 440                 do_i2c_scan(dev->name,&dev->i2c_client);
 441         return 0;
 442 }
 443
 444 int saa7134_i2c_unregister(struct saa7134_dev *dev)
 445 {
 446         i2c_del_adapter(&dev->i2c_adap);
 447         return 0;
 448 }
 449
 450 /* ----------------------------------------------------------- */
 451 /*
 452  * Local variables:
 453  * c-basic-offset: 8
 454  * End:
 455  */