drivers/i2c/busses/i2c-piix4.c

   1 /*
   2     piix4.c - Part of lm_sensors, Linux kernel modules for hardware
   3               monitoring
   4     Copyright (c) 1998 - 2002 Frodo Looijaard <frodol@dds.nl> and
   5     Philip Edelbrock <phil@netroedge.com>
   6
   7     This program is free software; you can redistribute it and/or modify
   8     it under the terms of the GNU General Public License as published by
   9     the Free Software Foundation; either version 2 of the License, or
  10     (at your option) any later version.
  11
  12     This program is distributed in the hope that it will be useful,
  13     but WITHOUT ANY WARRANTY; without even the implied warranty of
  14     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15     GNU General Public License for more details.
  16
  17     You should have received a copy of the GNU General Public License
  18     along with this program; if not, write to the Free Software
  19     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20 */
  21
  22 /*
  23    Supports:
  24         Intel PIIX4, 440MX
  25         Serverworks OSB4, CSB5, CSB6, HT-1000
  26         ATI IXP200, IXP300, IXP400, SB600, SB700, SB800
  27         SMSC Victory66
  28
  29    Note: we assume there can only be one device, with one SMBus interface.
  30 */
  31
  32 #include <linux/module.h>
  33 #include <linux/moduleparam.h>
  34 #include <linux/pci.h>
  35 #include <linux/kernel.h>
  36 #include <linux/delay.h>
  37 #include <linux/stddef.h>
  38 #include <linux/ioport.h>
  39 #include <linux/i2c.h>
  40 #include <linux/init.h>
  41 #include <linux/apm_bios.h>
  42 #include <linux/dmi.h>
  43 #include <asm/io.h>
  44
  45
  46 struct sd {
  47         const unsigned short mfr;
  48         const unsigned short dev;
  49         const unsigned char fn;
  50         const char *name;
  51 };
  52
  53 /* PIIX4 SMBus address offsets */
  54 #define SMBHSTSTS       (0 + piix4_smba)
  55 #define SMBHSLVSTS      (1 + piix4_smba)
  56 #define SMBHSTCNT       (2 + piix4_smba)
  57 #define SMBHSTCMD       (3 + piix4_smba)
  58 #define SMBHSTADD       (4 + piix4_smba)
  59 #define SMBHSTDAT0      (5 + piix4_smba)
  60 #define SMBHSTDAT1      (6 + piix4_smba)
  61 #define SMBBLKDAT       (7 + piix4_smba)
  62 #define SMBSLVCNT       (8 + piix4_smba)
  63 #define SMBSHDWCMD      (9 + piix4_smba)
  64 #define SMBSLVEVT       (0xA + piix4_smba)
  65 #define SMBSLVDAT       (0xC + piix4_smba)
  66
  67 /* count for request_region */
  68 #define SMBIOSIZE       8
  69
  70 /* PCI Address Constants */
  71 #define SMBBA           0x090
  72 #define SMBHSTCFG       0x0D2
  73 #define SMBSLVC         0x0D3
  74 #define SMBSHDW1        0x0D4
  75 #define SMBSHDW2        0x0D5
  76 #define SMBREV          0x0D6
  77
  78 /* Other settings */
  79 #define MAX_TIMEOUT     500
  80 #define  ENABLE_INT9    0
  81
  82 /* PIIX4 constants */
  83 #define PIIX4_QUICK             0x00
  84 #define PIIX4_BYTE              0x04
  85 #define PIIX4_BYTE_DATA         0x08
  86 #define PIIX4_WORD_DATA         0x0C
  87 #define PIIX4_BLOCK_DATA        0x14
  88
  89 /* insmod parameters */
  90
  91 /* If force is set to anything different from 0, we forcibly enable the
  92    PIIX4. DANGEROUS! */
  93 static int force;
  94 module_param (force, int, 0);
  95 MODULE_PARM_DESC(force, "Forcibly enable the PIIX4. DANGEROUS!");
  96
  97 /* If force_addr is set to anything different from 0, we forcibly enable
  98    the PIIX4 at the given address. VERY DANGEROUS! */
  99 static int force_addr;
 100 module_param (force_addr, int, 0);
 101 MODULE_PARM_DESC(force_addr,
 102                  "Forcibly enable the PIIX4 at the given address. "
 103                  "EXTREMELY DANGEROUS!");
 104
 105 static int piix4_transaction(void);
 106
 107 static unsigned short piix4_smba;
 108 static struct pci_driver piix4_driver;
 109 static struct i2c_adapter piix4_adapter;
 110
 111 static struct dmi_system_id __devinitdata piix4_dmi_table[] = {
 112         {
 113                 .ident = "IBM",
 114                 .matches = { DMI_MATCH(DMI_SYS_VENDOR, "IBM"), },
 115         },
 116         { },
 117 };
 118
 119 static int __devinit piix4_setup(struct pci_dev *PIIX4_dev,
 120                                 const struct pci_device_id *id)
 121 {
 122         unsigned char temp;
 123
 124         dev_info(&PIIX4_dev->dev, "Found %s device\n", pci_name(PIIX4_dev));
 125
 126         /* Don't access SMBus on IBM systems which get corrupted eeproms */
 127         if (dmi_check_system(piix4_dmi_table) &&
 128                         PIIX4_dev->vendor == PCI_VENDOR_ID_INTEL) {
 129                 dev_err(&PIIX4_dev->dev, "IBM system detected; this module "
 130                         "may corrupt your serial eeprom! Refusing to load "
 131                         "module!\n");
 132                 return -EPERM;
 133         }
 134
 135         /* Determine the address of the SMBus areas */
 136         if (force_addr) {
 137                 piix4_smba = force_addr & 0xfff0;
 138                 force = 0;
 139         } else {
 140                 pci_read_config_word(PIIX4_dev, SMBBA, &piix4_smba);
 141                 piix4_smba &= 0xfff0;
 142                 if(piix4_smba == 0) {
 143                         dev_err(&PIIX4_dev->dev, "SMB base address "
 144                                 "uninitialized - upgrade BIOS or use "
 145                                 "force_addr=0xaddr\n");
 146                         return -ENODEV;
 147                 }
 148         }
 149
 150         if (!request_region(piix4_smba, SMBIOSIZE, piix4_driver.name)) {
 151                 dev_err(&PIIX4_dev->dev, "SMB region 0x%x already in use!\n",
 152                         piix4_smba);
 153                 return -ENODEV;
 154         }
 155
 156         pci_read_config_byte(PIIX4_dev, SMBHSTCFG, &temp);
 157
 158         /* If force_addr is set, we program the new address here. Just to make
 159            sure, we disable the PIIX4 first. */
 160         if (force_addr) {
 161                 pci_write_config_byte(PIIX4_dev, SMBHSTCFG, temp & 0xfe);
 162                 pci_write_config_word(PIIX4_dev, SMBBA, piix4_smba);
 163                 pci_write_config_byte(PIIX4_dev, SMBHSTCFG, temp | 0x01);
 164                 dev_info(&PIIX4_dev->dev, "WARNING: SMBus interface set to "
 165                         "new address %04x!\n", piix4_smba);
 166         } else if ((temp & 1) == 0) {
 167                 if (force) {
 168                         /* This should never need to be done, but has been
 169                          * noted that many Dell machines have the SMBus
 170                          * interface on the PIIX4 disabled!? NOTE: This assumes
 171                          * I/O space and other allocations WERE done by the
 172                          * Bios!  Don't complain if your hardware does weird
 173                          * things after enabling this. :') Check for Bios
 174                          * updates before resorting to this.
 175                          */
 176                         pci_write_config_byte(PIIX4_dev, SMBHSTCFG,
 177                                               temp | 1);
 178                         dev_printk(KERN_NOTICE, &PIIX4_dev->dev,
 179                                 "WARNING: SMBus interface has been "
 180                                 "FORCEFULLY ENABLED!\n");
 181                 } else {
 182                         dev_err(&PIIX4_dev->dev,
 183                                 "Host SMBus controller not enabled!\n");
 184                         release_region(piix4_smba, SMBIOSIZE);
 185                         piix4_smba = 0;
 186                         return -ENODEV;
 187                 }
 188         }
 189
 190         if (((temp & 0x0E) == 8) || ((temp & 0x0E) == 2))
 191                 dev_dbg(&PIIX4_dev->dev, "Using Interrupt 9 for SMBus.\n");
 192         else if ((temp & 0x0E) == 0)
 193                 dev_dbg(&PIIX4_dev->dev, "Using Interrupt SMI# for SMBus.\n");
 194         else
 195                 dev_err(&PIIX4_dev->dev, "Illegal Interrupt configuration "
 196                         "(or code out of date)!\n");
 197
 198         pci_read_config_byte(PIIX4_dev, SMBREV, &temp);
 199         dev_dbg(&PIIX4_dev->dev, "SMBREV = 0x%X\n", temp);
 200         dev_dbg(&PIIX4_dev->dev, "SMBA = 0x%X\n", piix4_smba);
 201
 202         return 0;
 203 }
 204
 205 /* Another internally used function */
 206 static int piix4_transaction(void)
 207 {
 208         int temp;
 209         int result = 0;
 210         int timeout = 0;
 211
 212         dev_dbg(&piix4_adapter.dev, "Transaction (pre): CNT=%02x, CMD=%02x, "
 213                 "ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb_p(SMBHSTCNT),
 214                 inb_p(SMBHSTCMD), inb_p(SMBHSTADD), inb_p(SMBHSTDAT0),
 215                 inb_p(SMBHSTDAT1));
 216
 217         /* Make sure the SMBus host is ready to start transmitting */
 218         if ((temp = inb_p(SMBHSTSTS)) != 0x00) {
 219                 dev_dbg(&piix4_adapter.dev, "SMBus busy (%02x). "
 220                         "Resetting...\n", temp);
 221                 outb_p(temp, SMBHSTSTS);
 222                 if ((temp = inb_p(SMBHSTSTS)) != 0x00) {
 223                         dev_err(&piix4_adapter.dev, "Failed! (%02x)\n", temp);
 224                         return -1;
 225                 } else {
 226                         dev_dbg(&piix4_adapter.dev, "Successful!\n");
 227                 }
 228         }
 229
 230         /* start the transaction by setting bit 6 */
 231         outb_p(inb(SMBHSTCNT) | 0x040, SMBHSTCNT);
 232
 233         /* We will always wait for a fraction of a second! (See PIIX4 docs errata) */
 234         do {
 235                 msleep(1);
 236                 temp = inb_p(SMBHSTSTS);
 237         } while ((temp & 0x01) && (timeout++ < MAX_TIMEOUT));
 238
 239         /* If the SMBus is still busy, we give up */
 240         if (timeout >= MAX_TIMEOUT) {
 241                 dev_err(&piix4_adapter.dev, "SMBus Timeout!\n");
 242                 result = -1;
 243         }
 244
 245         if (temp & 0x10) {
 246                 result = -1;
 247                 dev_err(&piix4_adapter.dev, "Error: Failed bus transaction\n");
 248         }
 249
 250         if (temp & 0x08) {
 251                 result = -1;
 252                 dev_dbg(&piix4_adapter.dev, "Bus collision! SMBus may be "
 253                         "locked until next hard reset. (sorry!)\n");
 254                 /* Clock stops and slave is stuck in mid-transmission */
 255         }
 256
 257         if (temp & 0x04) {
 258                 result = -1;
 259                 dev_dbg(&piix4_adapter.dev, "Error: no response!\n");
 260         }
 261
 262         if (inb_p(SMBHSTSTS) != 0x00)
 263                 outb_p(inb(SMBHSTSTS), SMBHSTSTS);
 264
 265         if ((temp = inb_p(SMBHSTSTS)) != 0x00) {
 266                 dev_err(&piix4_adapter.dev, "Failed reset at end of "
 267                         "transaction (%02x)\n", temp);
 268         }
 269         dev_dbg(&piix4_adapter.dev, "Transaction (post): CNT=%02x, CMD=%02x, "
 270                 "ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb_p(SMBHSTCNT),
 271                 inb_p(SMBHSTCMD), inb_p(SMBHSTADD), inb_p(SMBHSTDAT0),
 272                 inb_p(SMBHSTDAT1));
 273         return result;
 274 }
 275
 276 /* Return -1 on error. */
 277 static s32 piix4_access(struct i2c_adapter * adap, u16 addr,
 278                  unsigned short flags, char read_write,
 279                  u8 command, int size, union i2c_smbus_data * data)
 280 {
 281         int i, len;
 282
 283         switch (size) {
 284         case I2C_SMBUS_PROC_CALL:
 285                 dev_err(&adap->dev, "I2C_SMBUS_PROC_CALL not supported!\n");
 286                 return -1;
 287         case I2C_SMBUS_QUICK:
 288                 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
 289                        SMBHSTADD);
 290                 size = PIIX4_QUICK;
 291                 break;
 292         case I2C_SMBUS_BYTE:
 293                 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
 294                        SMBHSTADD);
 295                 if (read_write == I2C_SMBUS_WRITE)
 296                         outb_p(command, SMBHSTCMD);
 297                 size = PIIX4_BYTE;
 298                 break;
 299         case I2C_SMBUS_BYTE_DATA:
 300                 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
 301                        SMBHSTADD);
 302                 outb_p(command, SMBHSTCMD);
 303                 if (read_write == I2C_SMBUS_WRITE)
 304                         outb_p(data->byte, SMBHSTDAT0);
 305                 size = PIIX4_BYTE_DATA;
 306                 break;
 307         case I2C_SMBUS_WORD_DATA:
 308                 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
 309                        SMBHSTADD);
 310                 outb_p(command, SMBHSTCMD);
 311                 if (read_write == I2C_SMBUS_WRITE) {
 312                         outb_p(data->word & 0xff, SMBHSTDAT0);
 313                         outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1);
 314                 }
 315                 size = PIIX4_WORD_DATA;
 316                 break;
 317         case I2C_SMBUS_BLOCK_DATA:
 318                 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
 319                        SMBHSTADD);
 320                 outb_p(command, SMBHSTCMD);
 321                 if (read_write == I2C_SMBUS_WRITE) {
 322                         len = data->block[0];
 323                         if (len < 0)
 324                                 len = 0;
 325                         if (len > 32)
 326                                 len = 32;
 327                         outb_p(len, SMBHSTDAT0);
 328                         i = inb_p(SMBHSTCNT);   /* Reset SMBBLKDAT */
 329                         for (i = 1; i <= len; i++)
 330                                 outb_p(data->block[i], SMBBLKDAT);
 331                 }
 332                 size = PIIX4_BLOCK_DATA;
 333                 break;
 334         }
 335
 336         outb_p((size & 0x1C) + (ENABLE_INT9 & 1), SMBHSTCNT);
 337
 338         if (piix4_transaction())        /* Error in transaction */
 339                 return -1;
 340
 341         if ((read_write == I2C_SMBUS_WRITE) || (size == PIIX4_QUICK))
 342                 return 0;
 343
 344
 345         switch (size) {
 346         case PIIX4_BYTE:        /* Where is the result put? I assume here it is in
 347                                    SMBHSTDAT0 but it might just as well be in the
 348                                    SMBHSTCMD. No clue in the docs */
 349
 350                 data->byte = inb_p(SMBHSTDAT0);
 351                 break;
 352         case PIIX4_BYTE_DATA:
 353                 data->byte = inb_p(SMBHSTDAT0);
 354                 break;
 355         case PIIX4_WORD_DATA:
 356                 data->word = inb_p(SMBHSTDAT0) + (inb_p(SMBHSTDAT1) << 8);
 357                 break;
 358         case PIIX4_BLOCK_DATA:
 359                 data->block[0] = inb_p(SMBHSTDAT0);
 360                 i = inb_p(SMBHSTCNT);   /* Reset SMBBLKDAT */
 361                 for (i = 1; i <= data->block[0]; i++)
 362                         data->block[i] = inb_p(SMBBLKDAT);
 363                 break;
 364         }
 365         return 0;
 366 }
 367
 368 static u32 piix4_func(struct i2c_adapter *adapter)
 369 {
 370         return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
 371             I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
 372             I2C_FUNC_SMBUS_BLOCK_DATA;
 373 }
 374
 375 static const struct i2c_algorithm smbus_algorithm = {
 376         .smbus_xfer     = piix4_access,
 377         .functionality  = piix4_func,
 378 };
 379
 380 static struct i2c_adapter piix4_adapter = {
 381         .owner          = THIS_MODULE,
 382         .id             = I2C_HW_SMBUS_PIIX4,
 383         .class          = I2C_CLASS_HWMON,
 384         .algo           = &smbus_algorithm,
 385 };
 386
 387 static struct pci_device_id piix4_ids[] = {
 388         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82371AB_3) },
 389         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82443MX_3) },
 390         { PCI_DEVICE(PCI_VENDOR_ID_EFAR, PCI_DEVICE_ID_EFAR_SLC90E66_3) },
 391         { PCI_DEVICE(PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_IXP200_SMBUS) },
 392         { PCI_DEVICE(PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_IXP300_SMBUS) },
 393         { PCI_DEVICE(PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_IXP400_SMBUS) },
 394         { PCI_DEVICE(PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_SBX00_SMBUS) },
 395         { PCI_DEVICE(PCI_VENDOR_ID_SERVERWORKS,
 396                      PCI_DEVICE_ID_SERVERWORKS_OSB4) },
 397         { PCI_DEVICE(PCI_VENDOR_ID_SERVERWORKS,
 398                      PCI_DEVICE_ID_SERVERWORKS_CSB5) },
 399         { PCI_DEVICE(PCI_VENDOR_ID_SERVERWORKS,
 400                      PCI_DEVICE_ID_SERVERWORKS_CSB6) },
 401         { PCI_DEVICE(PCI_VENDOR_ID_SERVERWORKS,
 402                      PCI_DEVICE_ID_SERVERWORKS_HT1000SB) },
 403         { 0, }
 404 };
 405
 406 MODULE_DEVICE_TABLE (pci, piix4_ids);
 407
 408 static int __devinit piix4_probe(struct pci_dev *dev,
 409                                 const struct pci_device_id *id)
 410 {
 411         int retval;
 412
 413         retval = piix4_setup(dev, id);
 414         if (retval)
 415                 return retval;
 416
 417         /* set up the sysfs linkage to our parent device */
 418         piix4_adapter.dev.parent = &dev->dev;
 419
 420         snprintf(piix4_adapter.name, sizeof(piix4_adapter.name),
 421                 "SMBus PIIX4 adapter at %04x", piix4_smba);
 422
 423         if ((retval = i2c_add_adapter(&piix4_adapter))) {
 424                 dev_err(&dev->dev, "Couldn't register adapter!\n");
 425                 release_region(piix4_smba, SMBIOSIZE);
 426                 piix4_smba = 0;
 427         }
 428
 429         return retval;
 430 }
 431
 432 static void __devexit piix4_remove(struct pci_dev *dev)
 433 {
 434         if (piix4_smba) {
 435                 i2c_del_adapter(&piix4_adapter);
 436                 release_region(piix4_smba, SMBIOSIZE);
 437                 piix4_smba = 0;
 438         }
 439 }
 440
 441 static struct pci_driver piix4_driver = {
 442         .name           = "piix4_smbus",
 443         .id_table       = piix4_ids,
 444         .probe          = piix4_probe,
 445         .remove         = __devexit_p(piix4_remove),
 446 };
 447
 448 static int __init i2c_piix4_init(void)
 449 {
 450         return pci_register_driver(&piix4_driver);
 451 }
 452
 453 static void __exit i2c_piix4_exit(void)
 454 {
 455         pci_unregister_driver(&piix4_driver);
 456 }
 457
 458 MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl> and "
 459                 "Philip Edelbrock <phil@netroedge.com>");
 460 MODULE_DESCRIPTION("PIIX4 SMBus driver");
 461 MODULE_LICENSE("GPL");
 462
 463 module_init(i2c_piix4_init);
 464 module_exit(i2c_piix4_exit);