drivers/i2c/busses/i2c-ali15x3.c

   1 /*
   2     ali15x3.c - Part of lm_sensors, Linux kernel modules for hardware
   3               monitoring
   4     Copyright (c) 1999  Frodo Looijaard <frodol@dds.nl> and
   5     Philip Edelbrock <phil@netroedge.com> and
   6     Mark D. Studebaker <mdsxyz123@yahoo.com>
   7
   8     This program is free software; you can redistribute it and/or modify
   9     it under the terms of the GNU General Public License as published by
  10     the Free Software Foundation; either version 2 of the License, or
  11     (at your option) any later version.
  12
  13     This program is distributed in the hope that it will be useful,
  14     but WITHOUT ANY WARRANTY; without even the implied warranty of
  15     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16     GNU General Public License for more details.
  17
  18     You should have received a copy of the GNU General Public License
  19     along with this program; if not, write to the Free Software
  20     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21 */
  22
  23 /*
  24     This is the driver for the SMB Host controller on
  25     Acer Labs Inc. (ALI) M1541 and M1543C South Bridges.
  26
  27     The M1543C is a South bridge for desktop systems.
  28     The M1533 is a South bridge for portable systems.
  29     They are part of the following ALI chipsets:
  30        "Aladdin Pro 2": Includes the M1621 Slot 1 North bridge
  31        with AGP and 100MHz CPU Front Side bus
  32        "Aladdin V": Includes the M1541 Socket 7 North bridge
  33        with AGP and 100MHz CPU Front Side bus
  34        "Aladdin IV": Includes the M1541 Socket 7 North bridge
  35        with host bus up to 83.3 MHz.
  36     For an overview of these chips see http://www.acerlabs.com
  37
  38     The M1533/M1543C devices appear as FOUR separate devices
  39     on the PCI bus. An output of lspci will show something similar
  40     to the following:
  41
  42         00:02.0 USB Controller: Acer Laboratories Inc. M5237
  43         00:03.0 Bridge: Acer Laboratories Inc. M7101
  44         00:07.0 ISA bridge: Acer Laboratories Inc. M1533
  45         00:0f.0 IDE interface: Acer Laboratories Inc. M5229
  46
  47     The SMB controller is part of the 7101 device, which is an
  48     ACPI-compliant Power Management Unit (PMU).
  49
  50     The whole 7101 device has to be enabled for the SMB to work.
  51     You can't just enable the SMB alone.
  52     The SMB and the ACPI have separate I/O spaces.
  53     We make sure that the SMB is enabled. We leave the ACPI alone.
  54
  55     This driver controls the SMB Host only.
  56     The SMB Slave controller on the M15X3 is not enabled.
  57
  58     This driver does not use interrupts.
  59 */
  60
  61 /* Note: we assume there can only be one ALI15X3, with one SMBus interface */
  62
  63 #include <linux/module.h>
  64 #include <linux/pci.h>
  65 #include <linux/kernel.h>
  66 #include <linux/stddef.h>
  67 #include <linux/sched.h>
  68 #include <linux/ioport.h>
  69 #include <linux/delay.h>
  70 #include <linux/i2c.h>
  71 #include <linux/init.h>
  72 #include <asm/io.h>
  73
  74 /* ALI15X3 SMBus address offsets */
  75 #define SMBHSTSTS       (0 + ali15x3_smba)
  76 #define SMBHSTCNT       (1 + ali15x3_smba)
  77 #define SMBHSTSTART     (2 + ali15x3_smba)
  78 #define SMBHSTCMD       (7 + ali15x3_smba)
  79 #define SMBHSTADD       (3 + ali15x3_smba)
  80 #define SMBHSTDAT0      (4 + ali15x3_smba)
  81 #define SMBHSTDAT1      (5 + ali15x3_smba)
  82 #define SMBBLKDAT       (6 + ali15x3_smba)
  83
  84 /* PCI Address Constants */
  85 #define SMBCOM          0x004
  86 #define SMBBA           0x014
  87 #define SMBATPC         0x05B   /* used to unlock xxxBA registers */
  88 #define SMBHSTCFG       0x0E0
  89 #define SMBSLVC         0x0E1
  90 #define SMBCLK          0x0E2
  91 #define SMBREV          0x008
  92
  93 /* Other settings */
  94 #define MAX_TIMEOUT             200     /* times 1/100 sec */
  95 #define ALI15X3_SMB_IOSIZE      32
  96
  97 /* this is what the Award 1004 BIOS sets them to on a ASUS P5A MB.
  98    We don't use these here. If the bases aren't set to some value we
  99    tell user to upgrade BIOS and we fail.
 100 */
 101 #define ALI15X3_SMB_DEFAULTBASE 0xE800
 102
 103 /* ALI15X3 address lock bits */
 104 #define ALI15X3_LOCK            0x06
 105
 106 /* ALI15X3 command constants */
 107 #define ALI15X3_ABORT           0x02
 108 #define ALI15X3_T_OUT           0x04
 109 #define ALI15X3_QUICK           0x00
 110 #define ALI15X3_BYTE            0x10
 111 #define ALI15X3_BYTE_DATA       0x20
 112 #define ALI15X3_WORD_DATA       0x30
 113 #define ALI15X3_BLOCK_DATA      0x40
 114 #define ALI15X3_BLOCK_CLR       0x80
 115
 116 /* ALI15X3 status register bits */
 117 #define ALI15X3_STS_IDLE        0x04
 118 #define ALI15X3_STS_BUSY        0x08
 119 #define ALI15X3_STS_DONE        0x10
 120 #define ALI15X3_STS_DEV         0x20    /* device error */
 121 #define ALI15X3_STS_COLL        0x40    /* collision or no response */
 122 #define ALI15X3_STS_TERM        0x80    /* terminated by abort */
 123 #define ALI15X3_STS_ERR         0xE0    /* all the bad error bits */
 124
 125
 126 /* If force_addr is set to anything different from 0, we forcibly enable
 127    the device at the given address. */
 128 static u16 force_addr;
 129 module_param(force_addr, ushort, 0);
 130 MODULE_PARM_DESC(force_addr,
 131                  "Initialize the base address of the i2c controller");
 132
 133 static struct pci_driver ali15x3_driver;
 134 static unsigned short ali15x3_smba;
 135
 136 static int ali15x3_setup(struct pci_dev *ALI15X3_dev)
 137 {
 138         u16 a;
 139         unsigned char temp;
 140
 141         /* Check the following things:
 142                 - SMB I/O address is initialized
 143                 - Device is enabled
 144                 - We can use the addresses
 145         */
 146
 147         /* Unlock the register.
 148            The data sheet says that the address registers are read-only
 149            if the lock bits are 1, but in fact the address registers
 150            are zero unless you clear the lock bits.
 151         */
 152         pci_read_config_byte(ALI15X3_dev, SMBATPC, &temp);
 153         if (temp & ALI15X3_LOCK) {
 154                 temp &= ~ALI15X3_LOCK;
 155                 pci_write_config_byte(ALI15X3_dev, SMBATPC, temp);
 156         }
 157
 158         /* Determine the address of the SMBus area */
 159         pci_read_config_word(ALI15X3_dev, SMBBA, &ali15x3_smba);
 160         ali15x3_smba &= (0xffff & ~(ALI15X3_SMB_IOSIZE - 1));
 161         if (ali15x3_smba == 0 && force_addr == 0) {
 162                 dev_err(&ALI15X3_dev->dev, "ALI15X3_smb region uninitialized "
 163                         "- upgrade BIOS or use force_addr=0xaddr\n");
 164                 return -ENODEV;
 165         }
 166
 167         if(force_addr)
 168                 ali15x3_smba = force_addr & ~(ALI15X3_SMB_IOSIZE - 1);
 169
 170         if (!request_region(ali15x3_smba, ALI15X3_SMB_IOSIZE,
 171                             ali15x3_driver.name)) {
 172                 dev_err(&ALI15X3_dev->dev,
 173                         "ALI15X3_smb region 0x%x already in use!\n",
 174                         ali15x3_smba);
 175                 return -ENODEV;
 176         }
 177
 178         if(force_addr) {
 179                 dev_info(&ALI15X3_dev->dev, "forcing ISA address 0x%04X\n",
 180                         ali15x3_smba);
 181                 if (PCIBIOS_SUCCESSFUL != pci_write_config_word(ALI15X3_dev,
 182                                                                 SMBBA,
 183                                                                 ali15x3_smba))
 184                         goto error;
 185                 if (PCIBIOS_SUCCESSFUL != pci_read_config_word(ALI15X3_dev,
 186                                                                 SMBBA, &a))
 187                         goto error;
 188                 if ((a & ~(ALI15X3_SMB_IOSIZE - 1)) != ali15x3_smba) {
 189                         /* make sure it works */
 190                         dev_err(&ALI15X3_dev->dev,
 191                                 "force address failed - not supported?\n");
 192                         goto error;
 193                 }
 194         }
 195         /* check if whole device is enabled */
 196         pci_read_config_byte(ALI15X3_dev, SMBCOM, &temp);
 197         if ((temp & 1) == 0) {
 198                 dev_info(&ALI15X3_dev->dev, "enabling SMBus device\n");
 199                 pci_write_config_byte(ALI15X3_dev, SMBCOM, temp | 0x01);
 200         }
 201
 202         /* Is SMB Host controller enabled? */
 203         pci_read_config_byte(ALI15X3_dev, SMBHSTCFG, &temp);
 204         if ((temp & 1) == 0) {
 205                 dev_info(&ALI15X3_dev->dev, "enabling SMBus controller\n");
 206                 pci_write_config_byte(ALI15X3_dev, SMBHSTCFG, temp | 0x01);
 207         }
 208
 209         /* set SMB clock to 74KHz as recommended in data sheet */
 210         pci_write_config_byte(ALI15X3_dev, SMBCLK, 0x20);
 211
 212         /*
 213           The interrupt routing for SMB is set up in register 0x77 in the
 214           1533 ISA Bridge device, NOT in the 7101 device.
 215           Don't bother with finding the 1533 device and reading the register.
 216         if ((....... & 0x0F) == 1)
 217                 dev_dbg(&ALI15X3_dev->dev, "ALI15X3 using Interrupt 9 for SMBus.\n");
 218         */
 219         pci_read_config_byte(ALI15X3_dev, SMBREV, &temp);
 220         dev_dbg(&ALI15X3_dev->dev, "SMBREV = 0x%X\n", temp);
 221         dev_dbg(&ALI15X3_dev->dev, "iALI15X3_smba = 0x%X\n", ali15x3_smba);
 222
 223         return 0;
 224 error:
 225         release_region(ali15x3_smba, ALI15X3_SMB_IOSIZE);
 226         return -ENODEV;
 227 }
 228
 229 /* Another internally used function */
 230 static int ali15x3_transaction(struct i2c_adapter *adap)
 231 {
 232         int temp;
 233         int result = 0;
 234         int timeout = 0;
 235
 236         dev_dbg(&adap->dev, "Transaction (pre): STS=%02x, CNT=%02x, CMD=%02x, "
 237                 "ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb_p(SMBHSTSTS),
 238                 inb_p(SMBHSTCNT), inb_p(SMBHSTCMD), inb_p(SMBHSTADD),
 239                 inb_p(SMBHSTDAT0), inb_p(SMBHSTDAT1));
 240
 241         /* get status */
 242         temp = inb_p(SMBHSTSTS);
 243
 244         /* Make sure the SMBus host is ready to start transmitting */
 245         /* Check the busy bit first */
 246         if (temp & ALI15X3_STS_BUSY) {
 247         /*
 248            If the host controller is still busy, it may have timed out in the
 249            previous transaction, resulting in a "SMBus Timeout" Dev.
 250            I've tried the following to reset a stuck busy bit.
 251                 1. Reset the controller with an ABORT command.
 252                    (this doesn't seem to clear the controller if an external
 253                    device is hung)
 254                 2. Reset the controller and the other SMBus devices with a
 255                    T_OUT command.  (this clears the host busy bit if an
 256                    external device is hung, but it comes back upon a new access
 257                    to a device)
 258                 3. Disable and reenable the controller in SMBHSTCFG
 259            Worst case, nothing seems to work except power reset.
 260         */
 261         /* Abort - reset the host controller */
 262         /*
 263            Try resetting entire SMB bus, including other devices -
 264            This may not work either - it clears the BUSY bit but
 265            then the BUSY bit may come back on when you try and use the chip again.
 266            If that's the case you are stuck.
 267         */
 268                 dev_info(&adap->dev, "Resetting entire SMB Bus to "
 269                         "clear busy condition (%02x)\n", temp);
 270                 outb_p(ALI15X3_T_OUT, SMBHSTCNT);
 271                 temp = inb_p(SMBHSTSTS);
 272         }
 273
 274         /* now check the error bits and the busy bit */
 275         if (temp & (ALI15X3_STS_ERR | ALI15X3_STS_BUSY)) {
 276                 /* do a clear-on-write */
 277                 outb_p(0xFF, SMBHSTSTS);
 278                 if ((temp = inb_p(SMBHSTSTS)) &
 279                     (ALI15X3_STS_ERR | ALI15X3_STS_BUSY)) {
 280                         /* this is probably going to be correctable only by a power reset
 281                            as one of the bits now appears to be stuck */
 282                         /* This may be a bus or device with electrical problems. */
 283                         dev_err(&adap->dev, "SMBus reset failed! (0x%02x) - "
 284                                 "controller or device on bus is probably hung\n",
 285                                 temp);
 286                         return -1;
 287                 }
 288         } else {
 289                 /* check and clear done bit */
 290                 if (temp & ALI15X3_STS_DONE) {
 291                         outb_p(temp, SMBHSTSTS);
 292                 }
 293         }
 294
 295         /* start the transaction by writing anything to the start register */
 296         outb_p(0xFF, SMBHSTSTART);
 297
 298         /* We will always wait for a fraction of a second! */
 299         timeout = 0;
 300         do {
 301                 msleep(1);
 302                 temp = inb_p(SMBHSTSTS);
 303         } while ((!(temp & (ALI15X3_STS_ERR | ALI15X3_STS_DONE)))
 304                  && (timeout++ < MAX_TIMEOUT));
 305
 306         /* If the SMBus is still busy, we give up */
 307         if (timeout >= MAX_TIMEOUT) {
 308                 result = -1;
 309                 dev_err(&adap->dev, "SMBus Timeout!\n");
 310         }
 311
 312         if (temp & ALI15X3_STS_TERM) {
 313                 result = -1;
 314                 dev_dbg(&adap->dev, "Error: Failed bus transaction\n");
 315         }
 316
 317         /*
 318           Unfortunately the ALI SMB controller maps "no response" and "bus
 319           collision" into a single bit. No reponse is the usual case so don't
 320           do a printk.
 321           This means that bus collisions go unreported.
 322         */
 323         if (temp & ALI15X3_STS_COLL) {
 324                 result = -1;
 325                 dev_dbg(&adap->dev,
 326                         "Error: no response or bus collision ADD=%02x\n",
 327                         inb_p(SMBHSTADD));
 328         }
 329
 330         /* haven't ever seen this */
 331         if (temp & ALI15X3_STS_DEV) {
 332                 result = -1;
 333                 dev_err(&adap->dev, "Error: device error\n");
 334         }
 335         dev_dbg(&adap->dev, "Transaction (post): STS=%02x, CNT=%02x, CMD=%02x, "
 336                 "ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb_p(SMBHSTSTS),
 337                 inb_p(SMBHSTCNT), inb_p(SMBHSTCMD), inb_p(SMBHSTADD),
 338                 inb_p(SMBHSTDAT0), inb_p(SMBHSTDAT1));
 339         return result;
 340 }
 341
 342 /* Return -1 on error. */
 343 static s32 ali15x3_access(struct i2c_adapter * adap, u16 addr,
 344                    unsigned short flags, char read_write, u8 command,
 345                    int size, union i2c_smbus_data * data)
 346 {
 347         int i, len;
 348         int temp;
 349         int timeout;
 350
 351         /* clear all the bits (clear-on-write) */
 352         outb_p(0xFF, SMBHSTSTS);
 353         /* make sure SMBus is idle */
 354         temp = inb_p(SMBHSTSTS);
 355         for (timeout = 0;
 356              (timeout < MAX_TIMEOUT) && !(temp & ALI15X3_STS_IDLE);
 357              timeout++) {
 358                 msleep(1);
 359                 temp = inb_p(SMBHSTSTS);
 360         }
 361         if (timeout >= MAX_TIMEOUT) {
 362                 dev_err(&adap->dev, "Idle wait Timeout! STS=0x%02x\n", temp);
 363         }
 364
 365         switch (size) {
 366         case I2C_SMBUS_PROC_CALL:
 367                 dev_err(&adap->dev, "I2C_SMBUS_PROC_CALL not supported!\n");
 368                 return -1;
 369         case I2C_SMBUS_QUICK:
 370                 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
 371                        SMBHSTADD);
 372                 size = ALI15X3_QUICK;
 373                 break;
 374         case I2C_SMBUS_BYTE:
 375                 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
 376                        SMBHSTADD);
 377                 if (read_write == I2C_SMBUS_WRITE)
 378                         outb_p(command, SMBHSTCMD);
 379                 size = ALI15X3_BYTE;
 380                 break;
 381         case I2C_SMBUS_BYTE_DATA:
 382                 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
 383                        SMBHSTADD);
 384                 outb_p(command, SMBHSTCMD);
 385                 if (read_write == I2C_SMBUS_WRITE)
 386                         outb_p(data->byte, SMBHSTDAT0);
 387                 size = ALI15X3_BYTE_DATA;
 388                 break;
 389         case I2C_SMBUS_WORD_DATA:
 390                 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
 391                        SMBHSTADD);
 392                 outb_p(command, SMBHSTCMD);
 393                 if (read_write == I2C_SMBUS_WRITE) {
 394                         outb_p(data->word & 0xff, SMBHSTDAT0);
 395                         outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1);
 396                 }
 397                 size = ALI15X3_WORD_DATA;
 398                 break;
 399         case I2C_SMBUS_BLOCK_DATA:
 400                 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
 401                        SMBHSTADD);
 402                 outb_p(command, SMBHSTCMD);
 403                 if (read_write == I2C_SMBUS_WRITE) {
 404                         len = data->block[0];
 405                         if (len < 0) {
 406                                 len = 0;
 407                                 data->block[0] = len;
 408                         }
 409                         if (len > 32) {
 410                                 len = 32;
 411                                 data->block[0] = len;
 412                         }
 413                         outb_p(len, SMBHSTDAT0);
 414                         /* Reset SMBBLKDAT */
 415                         outb_p(inb_p(SMBHSTCNT) | ALI15X3_BLOCK_CLR, SMBHSTCNT);
 416                         for (i = 1; i <= len; i++)
 417                                 outb_p(data->block[i], SMBBLKDAT);
 418                 }
 419                 size = ALI15X3_BLOCK_DATA;
 420                 break;
 421         }
 422
 423         outb_p(size, SMBHSTCNT);        /* output command */
 424
 425         if (ali15x3_transaction(adap))  /* Error in transaction */
 426                 return -1;
 427
 428         if ((read_write == I2C_SMBUS_WRITE) || (size == ALI15X3_QUICK))
 429                 return 0;
 430
 431
 432         switch (size) {
 433         case ALI15X3_BYTE:      /* Result put in SMBHSTDAT0 */
 434                 data->byte = inb_p(SMBHSTDAT0);
 435                 break;
 436         case ALI15X3_BYTE_DATA:
 437                 data->byte = inb_p(SMBHSTDAT0);
 438                 break;
 439         case ALI15X3_WORD_DATA:
 440                 data->word = inb_p(SMBHSTDAT0) + (inb_p(SMBHSTDAT1) << 8);
 441                 break;
 442         case ALI15X3_BLOCK_DATA:
 443                 len = inb_p(SMBHSTDAT0);
 444                 if (len > 32)
 445                         len = 32;
 446                 data->block[0] = len;
 447                 /* Reset SMBBLKDAT */
 448                 outb_p(inb_p(SMBHSTCNT) | ALI15X3_BLOCK_CLR, SMBHSTCNT);
 449                 for (i = 1; i <= data->block[0]; i++) {
 450                         data->block[i] = inb_p(SMBBLKDAT);
 451                         dev_dbg(&adap->dev, "Blk: len=%d, i=%d, data=%02x\n",
 452                                 len, i, data->block[i]);
 453                 }
 454                 break;
 455         }
 456         return 0;
 457 }
 458
 459 static u32 ali15x3_func(struct i2c_adapter *adapter)
 460 {
 461         return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
 462             I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
 463             I2C_FUNC_SMBUS_BLOCK_DATA;
 464 }
 465
 466 static struct i2c_algorithm smbus_algorithm = {
 467         .smbus_xfer     = ali15x3_access,
 468         .functionality  = ali15x3_func,
 469 };
 470
 471 static struct i2c_adapter ali15x3_adapter = {
 472         .owner          = THIS_MODULE,
 473         .class          = I2C_CLASS_HWMON,
 474         .algo           = &smbus_algorithm,
 475 };
 476
 477 static struct pci_device_id ali15x3_ids[] = {
 478         { PCI_DEVICE(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M7101) },
 479         { 0, }
 480 };
 481
 482 MODULE_DEVICE_TABLE (pci, ali15x3_ids);
 483
 484 static int __devinit ali15x3_probe(struct pci_dev *dev, const struct pci_device_id *id)
 485 {
 486         if (ali15x3_setup(dev)) {
 487                 dev_err(&dev->dev,
 488                         "ALI15X3 not detected, module not inserted.\n");
 489                 return -ENODEV;
 490         }
 491
 492         /* set up the driverfs linkage to our parent device */
 493         ali15x3_adapter.dev.parent = &dev->dev;
 494
 495         snprintf(ali15x3_adapter.name, I2C_NAME_SIZE,
 496                 "SMBus ALI15X3 adapter at %04x", ali15x3_smba);
 497         return i2c_add_adapter(&ali15x3_adapter);
 498 }
 499
 500 static void __devexit ali15x3_remove(struct pci_dev *dev)
 501 {
 502         i2c_del_adapter(&ali15x3_adapter);
 503         release_region(ali15x3_smba, ALI15X3_SMB_IOSIZE);
 504 }
 505
 506 static struct pci_driver ali15x3_driver = {
 507         .name           = "ali15x3_smbus",
 508         .id_table       = ali15x3_ids,
 509         .probe          = ali15x3_probe,
 510         .remove         = __devexit_p(ali15x3_remove),
 511 };
 512
 513 static int __init i2c_ali15x3_init(void)
 514 {
 515         return pci_register_driver(&ali15x3_driver);
 516 }
 517
 518 static void __exit i2c_ali15x3_exit(void)
 519 {
 520         pci_unregister_driver(&ali15x3_driver);
 521 }
 522
 523 MODULE_AUTHOR ("Frodo Looijaard <frodol@dds.nl>, "
 524                 "Philip Edelbrock <phil@netroedge.com>, "
 525                 "and Mark D. Studebaker <mdsxyz123@yahoo.com>");
 526 MODULE_DESCRIPTION("ALI15X3 SMBus driver");
 527 MODULE_LICENSE("GPL");
 528
 529 module_init(i2c_ali15x3_init);
 530 module_exit(i2c_ali15x3_exit);