linux/drivers/i2c/busses/i2c-piix4.c
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   1/*
   2    Copyright (c) 1998 - 2002 Frodo Looijaard <frodol@dds.nl> and
   3    Philip Edelbrock <phil@netroedge.com>
   4
   5    This program is free software; you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation; either version 2 of the License, or
   8    (at your option) any later version.
   9
  10    This program is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13    GNU General Public License for more details.
  14*/
  15
  16/*
  17   Supports:
  18        Intel PIIX4, 440MX
  19        Serverworks OSB4, CSB5, CSB6, HT-1000, HT-1100
  20        ATI IXP200, IXP300, IXP400, SB600, SB700/SP5100, SB800
  21        AMD Hudson-2, ML, CZ
  22        SMSC Victory66
  23
  24   Note: we assume there can only be one device, with one or more
  25   SMBus interfaces.
  26   The device can register multiple i2c_adapters (up to PIIX4_MAX_ADAPTERS).
  27   For devices supporting multiple ports the i2c_adapter should provide
  28   an i2c_algorithm to access them.
  29*/
  30
  31#include <linux/module.h>
  32#include <linux/moduleparam.h>
  33#include <linux/pci.h>
  34#include <linux/kernel.h>
  35#include <linux/delay.h>
  36#include <linux/stddef.h>
  37#include <linux/ioport.h>
  38#include <linux/i2c.h>
  39#include <linux/slab.h>
  40#include <linux/dmi.h>
  41#include <linux/acpi.h>
  42#include <linux/io.h>
  43#include <linux/mutex.h>
  44
  45
  46/* PIIX4 SMBus address offsets */
  47#define SMBHSTSTS       (0 + piix4_smba)
  48#define SMBHSLVSTS      (1 + piix4_smba)
  49#define SMBHSTCNT       (2 + piix4_smba)
  50#define SMBHSTCMD       (3 + piix4_smba)
  51#define SMBHSTADD       (4 + piix4_smba)
  52#define SMBHSTDAT0      (5 + piix4_smba)
  53#define SMBHSTDAT1      (6 + piix4_smba)
  54#define SMBBLKDAT       (7 + piix4_smba)
  55#define SMBSLVCNT       (8 + piix4_smba)
  56#define SMBSHDWCMD      (9 + piix4_smba)
  57#define SMBSLVEVT       (0xA + piix4_smba)
  58#define SMBSLVDAT       (0xC + piix4_smba)
  59
  60/* count for request_region */
  61#define SMBIOSIZE       9
  62
  63/* PCI Address Constants */
  64#define SMBBA           0x090
  65#define SMBHSTCFG       0x0D2
  66#define SMBSLVC         0x0D3
  67#define SMBSHDW1        0x0D4
  68#define SMBSHDW2        0x0D5
  69#define SMBREV          0x0D6
  70
  71/* Other settings */
  72#define MAX_TIMEOUT     500
  73#define  ENABLE_INT9    0
  74
  75/* PIIX4 constants */
  76#define PIIX4_QUICK             0x00
  77#define PIIX4_BYTE              0x04
  78#define PIIX4_BYTE_DATA         0x08
  79#define PIIX4_WORD_DATA         0x0C
  80#define PIIX4_BLOCK_DATA        0x14
  81
  82/* Multi-port constants */
  83#define PIIX4_MAX_ADAPTERS 4
  84
  85/* SB800 constants */
  86#define SB800_PIIX4_SMB_IDX             0xcd6
  87
  88/*
  89 * SB800 port is selected by bits 2:1 of the smb_en register (0x2c)
  90 * or the smb_sel register (0x2e), depending on bit 0 of register 0x2f.
  91 * Hudson-2/Bolton port is always selected by bits 2:1 of register 0x2f.
  92 */
  93#define SB800_PIIX4_PORT_IDX            0x2c
  94#define SB800_PIIX4_PORT_IDX_ALT        0x2e
  95#define SB800_PIIX4_PORT_IDX_SEL        0x2f
  96#define SB800_PIIX4_PORT_IDX_MASK       0x06
  97
  98/* insmod parameters */
  99
 100/* If force is set to anything different from 0, we forcibly enable the
 101   PIIX4. DANGEROUS! */
 102static int force;
 103module_param (force, int, 0);
 104MODULE_PARM_DESC(force, "Forcibly enable the PIIX4. DANGEROUS!");
 105
 106/* If force_addr is set to anything different from 0, we forcibly enable
 107   the PIIX4 at the given address. VERY DANGEROUS! */
 108static int force_addr;
 109module_param (force_addr, int, 0);
 110MODULE_PARM_DESC(force_addr,
 111                 "Forcibly enable the PIIX4 at the given address. "
 112                 "EXTREMELY DANGEROUS!");
 113
 114static int srvrworks_csb5_delay;
 115static struct pci_driver piix4_driver;
 116
 117static const struct dmi_system_id piix4_dmi_blacklist[] = {
 118        {
 119                .ident = "Sapphire AM2RD790",
 120                .matches = {
 121                        DMI_MATCH(DMI_BOARD_VENDOR, "SAPPHIRE Inc."),
 122                        DMI_MATCH(DMI_BOARD_NAME, "PC-AM2RD790"),
 123                },
 124        },
 125        {
 126                .ident = "DFI Lanparty UT 790FX",
 127                .matches = {
 128                        DMI_MATCH(DMI_BOARD_VENDOR, "DFI Inc."),
 129                        DMI_MATCH(DMI_BOARD_NAME, "LP UT 790FX"),
 130                },
 131        },
 132        { }
 133};
 134
 135/* The IBM entry is in a separate table because we only check it
 136   on Intel-based systems */
 137static const struct dmi_system_id piix4_dmi_ibm[] = {
 138        {
 139                .ident = "IBM",
 140                .matches = { DMI_MATCH(DMI_SYS_VENDOR, "IBM"), },
 141        },
 142        { },
 143};
 144
 145/*
 146 * SB800 globals
 147 * piix4_mutex_sb800 protects piix4_port_sel_sb800 and the pair
 148 * of I/O ports at SB800_PIIX4_SMB_IDX.
 149 */
 150static DEFINE_MUTEX(piix4_mutex_sb800);
 151static u8 piix4_port_sel_sb800;
 152static const char *piix4_main_port_names_sb800[PIIX4_MAX_ADAPTERS] = {
 153        " port 0", " port 2", " port 3", " port 4"
 154};
 155static const char *piix4_aux_port_name_sb800 = " port 1";
 156
 157struct i2c_piix4_adapdata {
 158        unsigned short smba;
 159
 160        /* SB800 */
 161        bool sb800_main;
 162        u8 port;                /* Port number, shifted */
 163};
 164
 165static int piix4_setup(struct pci_dev *PIIX4_dev,
 166                       const struct pci_device_id *id)
 167{
 168        unsigned char temp;
 169        unsigned short piix4_smba;
 170
 171        if ((PIIX4_dev->vendor == PCI_VENDOR_ID_SERVERWORKS) &&
 172            (PIIX4_dev->device == PCI_DEVICE_ID_SERVERWORKS_CSB5))
 173                srvrworks_csb5_delay = 1;
 174
 175        /* On some motherboards, it was reported that accessing the SMBus
 176           caused severe hardware problems */
 177        if (dmi_check_system(piix4_dmi_blacklist)) {
 178                dev_err(&PIIX4_dev->dev,
 179                        "Accessing the SMBus on this system is unsafe!\n");
 180                return -EPERM;
 181        }
 182
 183        /* Don't access SMBus on IBM systems which get corrupted eeproms */
 184        if (dmi_check_system(piix4_dmi_ibm) &&
 185                        PIIX4_dev->vendor == PCI_VENDOR_ID_INTEL) {
 186                dev_err(&PIIX4_dev->dev, "IBM system detected; this module "
 187                        "may corrupt your serial eeprom! Refusing to load "
 188                        "module!\n");
 189                return -EPERM;
 190        }
 191
 192        /* Determine the address of the SMBus areas */
 193        if (force_addr) {
 194                piix4_smba = force_addr & 0xfff0;
 195                force = 0;
 196        } else {
 197                pci_read_config_word(PIIX4_dev, SMBBA, &piix4_smba);
 198                piix4_smba &= 0xfff0;
 199                if(piix4_smba == 0) {
 200                        dev_err(&PIIX4_dev->dev, "SMBus base address "
 201                                "uninitialized - upgrade BIOS or use "
 202                                "force_addr=0xaddr\n");
 203                        return -ENODEV;
 204                }
 205        }
 206
 207        if (acpi_check_region(piix4_smba, SMBIOSIZE, piix4_driver.name))
 208                return -ENODEV;
 209
 210        if (!request_region(piix4_smba, SMBIOSIZE, piix4_driver.name)) {
 211                dev_err(&PIIX4_dev->dev, "SMBus region 0x%x already in use!\n",
 212                        piix4_smba);
 213                return -EBUSY;
 214        }
 215
 216        pci_read_config_byte(PIIX4_dev, SMBHSTCFG, &temp);
 217
 218        /* If force_addr is set, we program the new address here. Just to make
 219           sure, we disable the PIIX4 first. */
 220        if (force_addr) {
 221                pci_write_config_byte(PIIX4_dev, SMBHSTCFG, temp & 0xfe);
 222                pci_write_config_word(PIIX4_dev, SMBBA, piix4_smba);
 223                pci_write_config_byte(PIIX4_dev, SMBHSTCFG, temp | 0x01);
 224                dev_info(&PIIX4_dev->dev, "WARNING: SMBus interface set to "
 225                        "new address %04x!\n", piix4_smba);
 226        } else if ((temp & 1) == 0) {
 227                if (force) {
 228                        /* This should never need to be done, but has been
 229                         * noted that many Dell machines have the SMBus
 230                         * interface on the PIIX4 disabled!? NOTE: This assumes
 231                         * I/O space and other allocations WERE done by the
 232                         * Bios!  Don't complain if your hardware does weird
 233                         * things after enabling this. :') Check for Bios
 234                         * updates before resorting to this.
 235                         */
 236                        pci_write_config_byte(PIIX4_dev, SMBHSTCFG,
 237                                              temp | 1);
 238                        dev_notice(&PIIX4_dev->dev,
 239                                   "WARNING: SMBus interface has been FORCEFULLY ENABLED!\n");
 240                } else {
 241                        dev_err(&PIIX4_dev->dev,
 242                                "SMBus Host Controller not enabled!\n");
 243                        release_region(piix4_smba, SMBIOSIZE);
 244                        return -ENODEV;
 245                }
 246        }
 247
 248        if (((temp & 0x0E) == 8) || ((temp & 0x0E) == 2))
 249                dev_dbg(&PIIX4_dev->dev, "Using IRQ for SMBus\n");
 250        else if ((temp & 0x0E) == 0)
 251                dev_dbg(&PIIX4_dev->dev, "Using SMI# for SMBus\n");
 252        else
 253                dev_err(&PIIX4_dev->dev, "Illegal Interrupt configuration "
 254                        "(or code out of date)!\n");
 255
 256        pci_read_config_byte(PIIX4_dev, SMBREV, &temp);
 257        dev_info(&PIIX4_dev->dev,
 258                 "SMBus Host Controller at 0x%x, revision %d\n",
 259                 piix4_smba, temp);
 260
 261        return piix4_smba;
 262}
 263
 264static int piix4_setup_sb800(struct pci_dev *PIIX4_dev,
 265                             const struct pci_device_id *id, u8 aux)
 266{
 267        unsigned short piix4_smba;
 268        u8 smba_en_lo, smba_en_hi, smb_en, smb_en_status, port_sel;
 269        u8 i2ccfg, i2ccfg_offset = 0x10;
 270
 271        /* SB800 and later SMBus does not support forcing address */
 272        if (force || force_addr) {
 273                dev_err(&PIIX4_dev->dev, "SMBus does not support "
 274                        "forcing address!\n");
 275                return -EINVAL;
 276        }
 277
 278        /* Determine the address of the SMBus areas */
 279        if ((PIIX4_dev->vendor == PCI_VENDOR_ID_AMD &&
 280             PIIX4_dev->device == PCI_DEVICE_ID_AMD_HUDSON2_SMBUS &&
 281             PIIX4_dev->revision >= 0x41) ||
 282            (PIIX4_dev->vendor == PCI_VENDOR_ID_AMD &&
 283             PIIX4_dev->device == PCI_DEVICE_ID_AMD_KERNCZ_SMBUS &&
 284             PIIX4_dev->revision >= 0x49))
 285                smb_en = 0x00;
 286        else
 287                smb_en = (aux) ? 0x28 : 0x2c;
 288
 289        mutex_lock(&piix4_mutex_sb800);
 290        outb_p(smb_en, SB800_PIIX4_SMB_IDX);
 291        smba_en_lo = inb_p(SB800_PIIX4_SMB_IDX + 1);
 292        outb_p(smb_en + 1, SB800_PIIX4_SMB_IDX);
 293        smba_en_hi = inb_p(SB800_PIIX4_SMB_IDX + 1);
 294        mutex_unlock(&piix4_mutex_sb800);
 295
 296        if (!smb_en) {
 297                smb_en_status = smba_en_lo & 0x10;
 298                piix4_smba = smba_en_hi << 8;
 299                if (aux)
 300                        piix4_smba |= 0x20;
 301        } else {
 302                smb_en_status = smba_en_lo & 0x01;
 303                piix4_smba = ((smba_en_hi << 8) | smba_en_lo) & 0xffe0;
 304        }
 305
 306        if (!smb_en_status) {
 307                dev_err(&PIIX4_dev->dev,
 308                        "SMBus Host Controller not enabled!\n");
 309                return -ENODEV;
 310        }
 311
 312        if (acpi_check_region(piix4_smba, SMBIOSIZE, piix4_driver.name))
 313                return -ENODEV;
 314
 315        if (!request_region(piix4_smba, SMBIOSIZE, piix4_driver.name)) {
 316                dev_err(&PIIX4_dev->dev, "SMBus region 0x%x already in use!\n",
 317                        piix4_smba);
 318                return -EBUSY;
 319        }
 320
 321        /* Aux SMBus does not support IRQ information */
 322        if (aux) {
 323                dev_info(&PIIX4_dev->dev,
 324                         "Auxiliary SMBus Host Controller at 0x%x\n",
 325                         piix4_smba);
 326                return piix4_smba;
 327        }
 328
 329        /* Request the SMBus I2C bus config region */
 330        if (!request_region(piix4_smba + i2ccfg_offset, 1, "i2ccfg")) {
 331                dev_err(&PIIX4_dev->dev, "SMBus I2C bus config region "
 332                        "0x%x already in use!\n", piix4_smba + i2ccfg_offset);
 333                release_region(piix4_smba, SMBIOSIZE);
 334                return -EBUSY;
 335        }
 336        i2ccfg = inb_p(piix4_smba + i2ccfg_offset);
 337        release_region(piix4_smba + i2ccfg_offset, 1);
 338
 339        if (i2ccfg & 1)
 340                dev_dbg(&PIIX4_dev->dev, "Using IRQ for SMBus\n");
 341        else
 342                dev_dbg(&PIIX4_dev->dev, "Using SMI# for SMBus\n");
 343
 344        dev_info(&PIIX4_dev->dev,
 345                 "SMBus Host Controller at 0x%x, revision %d\n",
 346                 piix4_smba, i2ccfg >> 4);
 347
 348        /* Find which register is used for port selection */
 349        if (PIIX4_dev->vendor == PCI_VENDOR_ID_AMD) {
 350                piix4_port_sel_sb800 = SB800_PIIX4_PORT_IDX_ALT;
 351        } else {
 352                mutex_lock(&piix4_mutex_sb800);
 353                outb_p(SB800_PIIX4_PORT_IDX_SEL, SB800_PIIX4_SMB_IDX);
 354                port_sel = inb_p(SB800_PIIX4_SMB_IDX + 1);
 355                piix4_port_sel_sb800 = (port_sel & 0x01) ?
 356                                       SB800_PIIX4_PORT_IDX_ALT :
 357                                       SB800_PIIX4_PORT_IDX;
 358                mutex_unlock(&piix4_mutex_sb800);
 359        }
 360
 361        dev_info(&PIIX4_dev->dev,
 362                 "Using register 0x%02x for SMBus port selection\n",
 363                 (unsigned int)piix4_port_sel_sb800);
 364
 365        return piix4_smba;
 366}
 367
 368static int piix4_setup_aux(struct pci_dev *PIIX4_dev,
 369                           const struct pci_device_id *id,
 370                           unsigned short base_reg_addr)
 371{
 372        /* Set up auxiliary SMBus controllers found on some
 373         * AMD chipsets e.g. SP5100 (SB700 derivative) */
 374
 375        unsigned short piix4_smba;
 376
 377        /* Read address of auxiliary SMBus controller */
 378        pci_read_config_word(PIIX4_dev, base_reg_addr, &piix4_smba);
 379        if ((piix4_smba & 1) == 0) {
 380                dev_dbg(&PIIX4_dev->dev,
 381                        "Auxiliary SMBus controller not enabled\n");
 382                return -ENODEV;
 383        }
 384
 385        piix4_smba &= 0xfff0;
 386        if (piix4_smba == 0) {
 387                dev_dbg(&PIIX4_dev->dev,
 388                        "Auxiliary SMBus base address uninitialized\n");
 389                return -ENODEV;
 390        }
 391
 392        if (acpi_check_region(piix4_smba, SMBIOSIZE, piix4_driver.name))
 393                return -ENODEV;
 394
 395        if (!request_region(piix4_smba, SMBIOSIZE, piix4_driver.name)) {
 396                dev_err(&PIIX4_dev->dev, "Auxiliary SMBus region 0x%x "
 397                        "already in use!\n", piix4_smba);
 398                return -EBUSY;
 399        }
 400
 401        dev_info(&PIIX4_dev->dev,
 402                 "Auxiliary SMBus Host Controller at 0x%x\n",
 403                 piix4_smba);
 404
 405        return piix4_smba;
 406}
 407
 408static int piix4_transaction(struct i2c_adapter *piix4_adapter)
 409{
 410        struct i2c_piix4_adapdata *adapdata = i2c_get_adapdata(piix4_adapter);
 411        unsigned short piix4_smba = adapdata->smba;
 412        int temp;
 413        int result = 0;
 414        int timeout = 0;
 415
 416        dev_dbg(&piix4_adapter->dev, "Transaction (pre): CNT=%02x, CMD=%02x, "
 417                "ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb_p(SMBHSTCNT),
 418                inb_p(SMBHSTCMD), inb_p(SMBHSTADD), inb_p(SMBHSTDAT0),
 419                inb_p(SMBHSTDAT1));
 420
 421        /* Make sure the SMBus host is ready to start transmitting */
 422        if ((temp = inb_p(SMBHSTSTS)) != 0x00) {
 423                dev_dbg(&piix4_adapter->dev, "SMBus busy (%02x). "
 424                        "Resetting...\n", temp);
 425                outb_p(temp, SMBHSTSTS);
 426                if ((temp = inb_p(SMBHSTSTS)) != 0x00) {
 427                        dev_err(&piix4_adapter->dev, "Failed! (%02x)\n", temp);
 428                        return -EBUSY;
 429                } else {
 430                        dev_dbg(&piix4_adapter->dev, "Successful!\n");
 431                }
 432        }
 433
 434        /* start the transaction by setting bit 6 */
 435        outb_p(inb(SMBHSTCNT) | 0x040, SMBHSTCNT);
 436
 437        /* We will always wait for a fraction of a second! (See PIIX4 docs errata) */
 438        if (srvrworks_csb5_delay) /* Extra delay for SERVERWORKS_CSB5 */
 439                msleep(2);
 440        else
 441                msleep(1);
 442
 443        while ((++timeout < MAX_TIMEOUT) &&
 444               ((temp = inb_p(SMBHSTSTS)) & 0x01))
 445                msleep(1);
 446
 447        /* If the SMBus is still busy, we give up */
 448        if (timeout == MAX_TIMEOUT) {
 449                dev_err(&piix4_adapter->dev, "SMBus Timeout!\n");
 450                result = -ETIMEDOUT;
 451        }
 452
 453        if (temp & 0x10) {
 454                result = -EIO;
 455                dev_err(&piix4_adapter->dev, "Error: Failed bus transaction\n");
 456        }
 457
 458        if (temp & 0x08) {
 459                result = -EIO;
 460                dev_dbg(&piix4_adapter->dev, "Bus collision! SMBus may be "
 461                        "locked until next hard reset. (sorry!)\n");
 462                /* Clock stops and slave is stuck in mid-transmission */
 463        }
 464
 465        if (temp & 0x04) {
 466                result = -ENXIO;
 467                dev_dbg(&piix4_adapter->dev, "Error: no response!\n");
 468        }
 469
 470        if (inb_p(SMBHSTSTS) != 0x00)
 471                outb_p(inb(SMBHSTSTS), SMBHSTSTS);
 472
 473        if ((temp = inb_p(SMBHSTSTS)) != 0x00) {
 474                dev_err(&piix4_adapter->dev, "Failed reset at end of "
 475                        "transaction (%02x)\n", temp);
 476        }
 477        dev_dbg(&piix4_adapter->dev, "Transaction (post): CNT=%02x, CMD=%02x, "
 478                "ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb_p(SMBHSTCNT),
 479                inb_p(SMBHSTCMD), inb_p(SMBHSTADD), inb_p(SMBHSTDAT0),
 480                inb_p(SMBHSTDAT1));
 481        return result;
 482}
 483
 484/* Return negative errno on error. */
 485static s32 piix4_access(struct i2c_adapter * adap, u16 addr,
 486                 unsigned short flags, char read_write,
 487                 u8 command, int size, union i2c_smbus_data * data)
 488{
 489        struct i2c_piix4_adapdata *adapdata = i2c_get_adapdata(adap);
 490        unsigned short piix4_smba = adapdata->smba;
 491        int i, len;
 492        int status;
 493
 494        switch (size) {
 495        case I2C_SMBUS_QUICK:
 496                outb_p((addr << 1) | read_write,
 497                       SMBHSTADD);
 498                size = PIIX4_QUICK;
 499                break;
 500        case I2C_SMBUS_BYTE:
 501                outb_p((addr << 1) | read_write,
 502                       SMBHSTADD);
 503                if (read_write == I2C_SMBUS_WRITE)
 504                        outb_p(command, SMBHSTCMD);
 505                size = PIIX4_BYTE;
 506                break;
 507        case I2C_SMBUS_BYTE_DATA:
 508                outb_p((addr << 1) | read_write,
 509                       SMBHSTADD);
 510                outb_p(command, SMBHSTCMD);
 511                if (read_write == I2C_SMBUS_WRITE)
 512                        outb_p(data->byte, SMBHSTDAT0);
 513                size = PIIX4_BYTE_DATA;
 514                break;
 515        case I2C_SMBUS_WORD_DATA:
 516                outb_p((addr << 1) | read_write,
 517                       SMBHSTADD);
 518                outb_p(command, SMBHSTCMD);
 519                if (read_write == I2C_SMBUS_WRITE) {
 520                        outb_p(data->word & 0xff, SMBHSTDAT0);
 521                        outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1);
 522                }
 523                size = PIIX4_WORD_DATA;
 524                break;
 525        case I2C_SMBUS_BLOCK_DATA:
 526                outb_p((addr << 1) | read_write,
 527                       SMBHSTADD);
 528                outb_p(command, SMBHSTCMD);
 529                if (read_write == I2C_SMBUS_WRITE) {
 530                        len = data->block[0];
 531                        if (len == 0 || len > I2C_SMBUS_BLOCK_MAX)
 532                                return -EINVAL;
 533                        outb_p(len, SMBHSTDAT0);
 534                        inb_p(SMBHSTCNT);       /* Reset SMBBLKDAT */
 535                        for (i = 1; i <= len; i++)
 536                                outb_p(data->block[i], SMBBLKDAT);
 537                }
 538                size = PIIX4_BLOCK_DATA;
 539                break;
 540        default:
 541                dev_warn(&adap->dev, "Unsupported transaction %d\n", size);
 542                return -EOPNOTSUPP;
 543        }
 544
 545        outb_p((size & 0x1C) + (ENABLE_INT9 & 1), SMBHSTCNT);
 546
 547        status = piix4_transaction(adap);
 548        if (status)
 549                return status;
 550
 551        if ((read_write == I2C_SMBUS_WRITE) || (size == PIIX4_QUICK))
 552                return 0;
 553
 554
 555        switch (size) {
 556        case PIIX4_BYTE:
 557        case PIIX4_BYTE_DATA:
 558                data->byte = inb_p(SMBHSTDAT0);
 559                break;
 560        case PIIX4_WORD_DATA:
 561                data->word = inb_p(SMBHSTDAT0) + (inb_p(SMBHSTDAT1) << 8);
 562                break;
 563        case PIIX4_BLOCK_DATA:
 564                data->block[0] = inb_p(SMBHSTDAT0);
 565                if (data->block[0] == 0 || data->block[0] > I2C_SMBUS_BLOCK_MAX)
 566                        return -EPROTO;
 567                inb_p(SMBHSTCNT);       /* Reset SMBBLKDAT */
 568                for (i = 1; i <= data->block[0]; i++)
 569                        data->block[i] = inb_p(SMBBLKDAT);
 570                break;
 571        }
 572        return 0;
 573}
 574
 575/*
 576 * Handles access to multiple SMBus ports on the SB800.
 577 * The port is selected by bits 2:1 of the smb_en register (0x2c).
 578 * Returns negative errno on error.
 579 *
 580 * Note: The selected port must be returned to the initial selection to avoid
 581 * problems on certain systems.
 582 */
 583static s32 piix4_access_sb800(struct i2c_adapter *adap, u16 addr,
 584                 unsigned short flags, char read_write,
 585                 u8 command, int size, union i2c_smbus_data *data)
 586{
 587        struct i2c_piix4_adapdata *adapdata = i2c_get_adapdata(adap);
 588        unsigned short piix4_smba = adapdata->smba;
 589        int retries = MAX_TIMEOUT;
 590        int smbslvcnt;
 591        u8 smba_en_lo;
 592        u8 port;
 593        int retval;
 594
 595        mutex_lock(&piix4_mutex_sb800);
 596
 597        /* Request the SMBUS semaphore, avoid conflicts with the IMC */
 598        smbslvcnt  = inb_p(SMBSLVCNT);
 599        do {
 600                outb_p(smbslvcnt | 0x10, SMBSLVCNT);
 601
 602                /* Check the semaphore status */
 603                smbslvcnt  = inb_p(SMBSLVCNT);
 604                if (smbslvcnt & 0x10)
 605                        break;
 606
 607                usleep_range(1000, 2000);
 608        } while (--retries);
 609        /* SMBus is still owned by the IMC, we give up */
 610        if (!retries) {
 611                mutex_unlock(&piix4_mutex_sb800);
 612                return -EBUSY;
 613        }
 614
 615        outb_p(piix4_port_sel_sb800, SB800_PIIX4_SMB_IDX);
 616        smba_en_lo = inb_p(SB800_PIIX4_SMB_IDX + 1);
 617
 618        port = adapdata->port;
 619        if ((smba_en_lo & SB800_PIIX4_PORT_IDX_MASK) != port)
 620                outb_p((smba_en_lo & ~SB800_PIIX4_PORT_IDX_MASK) | port,
 621                       SB800_PIIX4_SMB_IDX + 1);
 622
 623        retval = piix4_access(adap, addr, flags, read_write,
 624                              command, size, data);
 625
 626        outb_p(smba_en_lo, SB800_PIIX4_SMB_IDX + 1);
 627
 628        /* Release the semaphore */
 629        outb_p(smbslvcnt | 0x20, SMBSLVCNT);
 630
 631        mutex_unlock(&piix4_mutex_sb800);
 632
 633        return retval;
 634}
 635
 636static u32 piix4_func(struct i2c_adapter *adapter)
 637{
 638        return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
 639            I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
 640            I2C_FUNC_SMBUS_BLOCK_DATA;
 641}
 642
 643static const struct i2c_algorithm smbus_algorithm = {
 644        .smbus_xfer     = piix4_access,
 645        .functionality  = piix4_func,
 646};
 647
 648static const struct i2c_algorithm piix4_smbus_algorithm_sb800 = {
 649        .smbus_xfer     = piix4_access_sb800,
 650        .functionality  = piix4_func,
 651};
 652
 653static const struct pci_device_id piix4_ids[] = {
 654        { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82371AB_3) },
 655        { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82443MX_3) },
 656        { PCI_DEVICE(PCI_VENDOR_ID_EFAR, PCI_DEVICE_ID_EFAR_SLC90E66_3) },
 657        { PCI_DEVICE(PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_IXP200_SMBUS) },
 658        { PCI_DEVICE(PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_IXP300_SMBUS) },
 659        { PCI_DEVICE(PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_IXP400_SMBUS) },
 660        { PCI_DEVICE(PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_SBX00_SMBUS) },
 661        { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_HUDSON2_SMBUS) },
 662        { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_KERNCZ_SMBUS) },
 663        { PCI_DEVICE(PCI_VENDOR_ID_SERVERWORKS,
 664                     PCI_DEVICE_ID_SERVERWORKS_OSB4) },
 665        { PCI_DEVICE(PCI_VENDOR_ID_SERVERWORKS,
 666                     PCI_DEVICE_ID_SERVERWORKS_CSB5) },
 667        { PCI_DEVICE(PCI_VENDOR_ID_SERVERWORKS,
 668                     PCI_DEVICE_ID_SERVERWORKS_CSB6) },
 669        { PCI_DEVICE(PCI_VENDOR_ID_SERVERWORKS,
 670                     PCI_DEVICE_ID_SERVERWORKS_HT1000SB) },
 671        { PCI_DEVICE(PCI_VENDOR_ID_SERVERWORKS,
 672                     PCI_DEVICE_ID_SERVERWORKS_HT1100LD) },
 673        { 0, }
 674};
 675
 676MODULE_DEVICE_TABLE (pci, piix4_ids);
 677
 678static struct i2c_adapter *piix4_main_adapters[PIIX4_MAX_ADAPTERS];
 679static struct i2c_adapter *piix4_aux_adapter;
 680
 681static int piix4_add_adapter(struct pci_dev *dev, unsigned short smba,
 682                             bool sb800_main, u8 port,
 683                             const char *name, struct i2c_adapter **padap)
 684{
 685        struct i2c_adapter *adap;
 686        struct i2c_piix4_adapdata *adapdata;
 687        int retval;
 688
 689        adap = kzalloc(sizeof(*adap), GFP_KERNEL);
 690        if (adap == NULL) {
 691                release_region(smba, SMBIOSIZE);
 692                return -ENOMEM;
 693        }
 694
 695        adap->owner = THIS_MODULE;
 696        adap->class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
 697        adap->algo = sb800_main ? &piix4_smbus_algorithm_sb800
 698                                : &smbus_algorithm;
 699
 700        adapdata = kzalloc(sizeof(*adapdata), GFP_KERNEL);
 701        if (adapdata == NULL) {
 702                kfree(adap);
 703                release_region(smba, SMBIOSIZE);
 704                return -ENOMEM;
 705        }
 706
 707        adapdata->smba = smba;
 708        adapdata->sb800_main = sb800_main;
 709        adapdata->port = port << 1;
 710
 711        /* set up the sysfs linkage to our parent device */
 712        adap->dev.parent = &dev->dev;
 713
 714        snprintf(adap->name, sizeof(adap->name),
 715                "SMBus PIIX4 adapter%s at %04x", name, smba);
 716
 717        i2c_set_adapdata(adap, adapdata);
 718
 719        retval = i2c_add_adapter(adap);
 720        if (retval) {
 721                dev_err(&dev->dev, "Couldn't register adapter!\n");
 722                kfree(adapdata);
 723                kfree(adap);
 724                release_region(smba, SMBIOSIZE);
 725                return retval;
 726        }
 727
 728        *padap = adap;
 729        return 0;
 730}
 731
 732static int piix4_add_adapters_sb800(struct pci_dev *dev, unsigned short smba)
 733{
 734        struct i2c_piix4_adapdata *adapdata;
 735        int port;
 736        int retval;
 737
 738        for (port = 0; port < PIIX4_MAX_ADAPTERS; port++) {
 739                retval = piix4_add_adapter(dev, smba, true, port,
 740                                           piix4_main_port_names_sb800[port],
 741                                           &piix4_main_adapters[port]);
 742                if (retval < 0)
 743                        goto error;
 744        }
 745
 746        return retval;
 747
 748error:
 749        dev_err(&dev->dev,
 750                "Error setting up SB800 adapters. Unregistering!\n");
 751        while (--port >= 0) {
 752                adapdata = i2c_get_adapdata(piix4_main_adapters[port]);
 753                if (adapdata->smba) {
 754                        i2c_del_adapter(piix4_main_adapters[port]);
 755                        kfree(adapdata);
 756                        kfree(piix4_main_adapters[port]);
 757                        piix4_main_adapters[port] = NULL;
 758                }
 759        }
 760
 761        return retval;
 762}
 763
 764static int piix4_probe(struct pci_dev *dev, const struct pci_device_id *id)
 765{
 766        int retval;
 767        bool is_sb800 = false;
 768
 769        if ((dev->vendor == PCI_VENDOR_ID_ATI &&
 770             dev->device == PCI_DEVICE_ID_ATI_SBX00_SMBUS &&
 771             dev->revision >= 0x40) ||
 772            dev->vendor == PCI_VENDOR_ID_AMD) {
 773                is_sb800 = true;
 774
 775                if (!request_region(SB800_PIIX4_SMB_IDX, 2, "smba_idx")) {
 776                        dev_err(&dev->dev,
 777                        "SMBus base address index region 0x%x already in use!\n",
 778                        SB800_PIIX4_SMB_IDX);
 779                        return -EBUSY;
 780                }
 781
 782                /* base address location etc changed in SB800 */
 783                retval = piix4_setup_sb800(dev, id, 0);
 784                if (retval < 0) {
 785                        release_region(SB800_PIIX4_SMB_IDX, 2);
 786                        return retval;
 787                }
 788
 789                /*
 790                 * Try to register multiplexed main SMBus adapter,
 791                 * give up if we can't
 792                 */
 793                retval = piix4_add_adapters_sb800(dev, retval);
 794                if (retval < 0) {
 795                        release_region(SB800_PIIX4_SMB_IDX, 2);
 796                        return retval;
 797                }
 798        } else {
 799                retval = piix4_setup(dev, id);
 800                if (retval < 0)
 801                        return retval;
 802
 803                /* Try to register main SMBus adapter, give up if we can't */
 804                retval = piix4_add_adapter(dev, retval, false, 0, "",
 805                                           &piix4_main_adapters[0]);
 806                if (retval < 0)
 807                        return retval;
 808        }
 809
 810        /* Check for auxiliary SMBus on some AMD chipsets */
 811        retval = -ENODEV;
 812
 813        if (dev->vendor == PCI_VENDOR_ID_ATI &&
 814            dev->device == PCI_DEVICE_ID_ATI_SBX00_SMBUS) {
 815                if (dev->revision < 0x40) {
 816                        retval = piix4_setup_aux(dev, id, 0x58);
 817                } else {
 818                        /* SB800 added aux bus too */
 819                        retval = piix4_setup_sb800(dev, id, 1);
 820                }
 821        }
 822
 823        if (dev->vendor == PCI_VENDOR_ID_AMD &&
 824            dev->device == PCI_DEVICE_ID_AMD_HUDSON2_SMBUS) {
 825                retval = piix4_setup_sb800(dev, id, 1);
 826        }
 827
 828        if (retval > 0) {
 829                /* Try to add the aux adapter if it exists,
 830                 * piix4_add_adapter will clean up if this fails */
 831                piix4_add_adapter(dev, retval, false, 0,
 832                                  is_sb800 ? piix4_aux_port_name_sb800 : "",
 833                                  &piix4_aux_adapter);
 834        }
 835
 836        return 0;
 837}
 838
 839static void piix4_adap_remove(struct i2c_adapter *adap)
 840{
 841        struct i2c_piix4_adapdata *adapdata = i2c_get_adapdata(adap);
 842
 843        if (adapdata->smba) {
 844                i2c_del_adapter(adap);
 845                if (adapdata->port == (0 << 1)) {
 846                        release_region(adapdata->smba, SMBIOSIZE);
 847                        if (adapdata->sb800_main)
 848                                release_region(SB800_PIIX4_SMB_IDX, 2);
 849                }
 850                kfree(adapdata);
 851                kfree(adap);
 852        }
 853}
 854
 855static void piix4_remove(struct pci_dev *dev)
 856{
 857        int port = PIIX4_MAX_ADAPTERS;
 858
 859        while (--port >= 0) {
 860                if (piix4_main_adapters[port]) {
 861                        piix4_adap_remove(piix4_main_adapters[port]);
 862                        piix4_main_adapters[port] = NULL;
 863                }
 864        }
 865
 866        if (piix4_aux_adapter) {
 867                piix4_adap_remove(piix4_aux_adapter);
 868                piix4_aux_adapter = NULL;
 869        }
 870}
 871
 872static struct pci_driver piix4_driver = {
 873        .name           = "piix4_smbus",
 874        .id_table       = piix4_ids,
 875        .probe          = piix4_probe,
 876        .remove         = piix4_remove,
 877};
 878
 879module_pci_driver(piix4_driver);
 880
 881MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl> and "
 882                "Philip Edelbrock <phil@netroedge.com>");
 883MODULE_DESCRIPTION("PIIX4 SMBus driver");
 884MODULE_LICENSE("GPL");
 885